- published: 18 Jul 2013
THE PHOENIX HE HELPED CREATE,
OUT OF CONTROL BOY WITHOUT A DAD,
SHOT THE GUN THAT STARTLED MY LIFE,
WHILE I DROVE HIM WITH A FORTY-FIVE.
FRIENDS FOR YEARS IMAGES IN RED,
BLEW OFF HIS OWN MOTHER-FUCKIN HEAD,
CONFIDENCE, DEATH, INSECURITY,
MEN FALL UNREALIZED, UNREALIZED, UNREALIZED.
MAKING A DECISION OF DEATH,
WHILE EVERYONE AROUND YOU PLED,
NOW YOU FLY IN PEACE, I HOPE, MY FRIEND,
A MAN CAN'T AVOID WHAT HE'S MEANT TO DO,
WHEN HE'S MEANT TO DO IT,
EVEN IF HE DOESN'T REALLY WANT TO,
MY MEMORIES ARE OF FUN AND FRIENDSHIP,
OF WEAKNESS WITHIN THE STRENGTH OF YOUTH,
FOR REASONS UNDEFINED, REASONS UNDEFINED,
REASONS UNDEFINED, REASONS UNDEFINED.
FRIENDS FOR YEARS IMAGES IN RED,
BLEW OFF HIS OWN MOTHER-FUCKIN HEAD,
CONFIDENCE, DEATH, INSECURITY,
MEN FALL UNREALIZED,
DON'T YOU REALIZE, EVIL, LIVES IN THE MOTHER-FUCKING SKIN,
DON'T YOU REALIZE, EVIL, LIVES IN THE MOTHER-FUCKING SKIN,
UNREALIZED, UNREALIZED.
DON'T YOU, REALIZE, EVIL, LIVES IN THE MOTHER-FUCKING SKIN,
DON'T YOU, REALIZE , THAT EVIL, LIVES IN THE MOTHER-FUCKING SKIN
WHY THE FUCK DID YOU TAKE HIM AWAY FROM US,
When you scream aloud
(Heads down Heads down)
That's when I plan to
(Rise up Rise up)
When you scream aloud
(We're doomed We're doomed)
That's when I plan to prove myself to you
I've never gotten the simple thrill of a solo day
I've never seen the point in you killing you
I've always backed my words with what I do
I'll always bite my tongue to comfort you
I'll be my superhero #1
I'll save me from myself
I, I rise,
Above the sun in the sky
Above that look in your eyes
MY PRIDE
Sister you know me
(Sister you know me)
Mother you made me
Lover what do you offer me
Father teach me
Brother protect
Lover what do you have for me
I'll be my superhero #1
I'll save me from myself
I'll be your superhero #1
I'll save you, I save
I'll save you
Your eyes deny a life that dulls your pride
too long
this has been done
it’s hiding
but something is wrong
pretend not to see it
the vision that feel it
i turn my head once more
wipe the tears from my eyes
i feel it’s no surprise
picture perfect
it’s not worth it
nothing rules forever
picture perfect
it’s not worth it
nothing rules forever
too late
the damage is done
helpless
i was too young
and though i mean it
i pray to believe it
just lying to myself
and so i paint what i want
the color to blacken my heart
picture perfect
it’s not worth it
nothing rules forever
picture perfect
it’s not worth it
nothing rules forever
after all
nothing is as it seems
I’m lost in this dream
nothing is as it seems, yeah
picture perfect
it’s not worth it
nothing rules forever
picture perfect
it’s not worth it
nothing rules forever
picture perfect
picture perfect
nothing lasts forever
I'll mimic everything you are to me
The way you walk, the way you talk
The way you breathe
Obsessions, Obsessing
Obsessing, Obsessions
Sing a song, sing your little song
Make it all make sense to me
Obsessing, Obsessions
Can't you see you are what I want my life to be
Oh can't you see you are me, can't you
You are me, dear god please
I don't wanna be everything that this god has planned for me
Can't you see you are my everything
I can't give everything this world will expect from me
You are my everything
Obsessions, Obsessing
Obsessing, Obsessions
When I'm through making me you
I'll be the best you that I can be
Obsessions
Can't you see how perfect you are to me
Can't you see you are me, can't you
See you walk like so
And you talk just like this
Could I be you if I, if I think like you
Can't you see how much you mean to me
I'm not obsessing
Can't you see how much I want your life for me
It's not an obsession
I wanna be just like you
Can't you see you are my everything
Can't you see you are me, you are
Can't you see how much you mean to me
Can't you see you are me
Can't you see you are my everything
Can't you see you are me, you are
can't you see how much I want your life for me
I keep your face deep inside, try to hide
All my memories bring you up again, up again
I keep a place deep inside try to hide you
All my hate speaks your name again, name again
Love, hate, game
Sinner, saint, same
Don't you recall what you did to me
Look at me now
Don't you remember what you've done to me
Look at me
I wish my pain onto you, all onto you
All the anger that you've spun in me, spun in me
Your mark was deep oh so true, shame on you
My mistrust was all from you, all from you
RIGHT! RIGHT!
1, 2 a million words for you
You are so perfect
Every time I swear I curse you
You're so damn faceless
With every look you drew me in
You were so perfect
Your games wore thin so says,
I keep my pain deep inside try to hide you
All your words bring me, bring me down again
no one cares what you offer
no one cares what you think
no one cares about anyone out there
and nobody is listening
you better say it like it is
you better say it like it is
say it, like it is, motherfucker say it like it is
say it, like it is
you better say it like it is
say it, like it is, motherfucker say it like it is
there’s no expectation
there’s no belief, yeah
I’ve given in to my hope and I’m feeling
my life is drained out me
you better say it like it is
you better say it like it is
say it, like it is, motherfucker say it like it is
say it like it is
you better say it like it is
say it, like it is, motherfucker say it like it is
you have underestimated me
I’ll tell what the hell i think
There’s no more hope, no more dream
no truth to anything
may i have your attention please
I’ll tell what i think
There’s no more hope, no more dream
no truth to anything
say it, like it is
motherfucker say it like it is
say it, like it is
motherfucker say it like it is
say it, like it is
motherfucker say it like it is
you have underestimated me
I’ll tell what the hell i think
There’s no more hope, no more dream
no truth to anything
say it, like it is
motherfucker say it like it is
say it, like it is
Did you think you'd be alone?
Did your life turn out the wayyou wanted?
You worked your fingers to the bone
Now you stare at the four walls that own you
You must break, you must break away
All your world has turned to grey
The colour on your life has gone and left you
What once you had has gone away
Consuming are the thoughts you just won't let go
The photos that you have will fade
Is'nt that enough of a sign to show you
That everything in life will change
The hand that you have been dealt must not own you
You must break, you must break away
All your world has turned to grey
The colour on your life has gone and left you
What once you had has gone away
My life is complicated
I tried but it's too late an
Just when i think that it's ok
This place has overtaken
More and more than I'm here
It's all fake, I can't tell
I think i finally understand
How i got this way
Every day I think that I'm Jaded
More than I can admit
In every way I think that I'm jaded, jaded
To all that I have hated
I can't begin to state that
In every way that I think
My brain's activated
More and more than I'm here
It's all fake, I can't tell
I think i finally understand
How i got this way
Every day I think that I'm Jaded
More than I can admit
In every way I think that I'm jaded, jaded
I'm JADED!
There is no way that I can turn back
I see all things and it's crystal clear, it's clear
Living here is war on my life
It has changed every piece of me
(chorus x2)
Every day I think that I'm Jaded
More than I can admit
In every way I think that I'm jaded, jaded
you tried to carry this
on your shoulders
how do you expect make it all alone
there’s no reason to insist
pushing further
i can take away your fear
i can make it disappear
call out my name
I’ll be there for you
call out my name
I’ll be there
a picture paints a thousand words
like the silence
to sacrifice yourself
it’s not the way things should be
open arms are raging out
I’m coming for you now
i can take away your fear
i can make it disappear
call out my name
I’ll be there for you
call out my name
I’ll be there
call out my name
and i will serve you
call out my name
I’ll be there, yeah
each day you break arms stronger
no matter what cloud you're under
offering yourself to this
it’s not the way
it’s not the way into there
call out my name
i will save you
call out my name
I’ll be there
call out my name
i will be there for you
call out my name
I’ll be there
call out my name
call out my name
LET IT GO
How far will a falling star take me
How far can I go can I go
Gotta be what the nightmare made me
Gotta be gotta be what I see
Jump clear of the falling parts from me
How far will they go will they go
Can't give what you need from me baby
Just let it go
Bringing me down break me down sweet sugar
Bringing me down break me down
Breaking me down to the ground sweet baby
Breaking me down to the ground
Too much is made of what's in me
Not enough about how I strive
Keep an eye on your world it's cheating
Keep an eye keep an eye on me
Deep inside there's a little place for me
A little place for me
Can't give what you want from me baby
Just leave it be
Sweet razor wound
Deep down slice my groove
Sweet razor wound
Deep down C'mon and slice it
How far did the falling star take me
How far did it go did it go
Had to be what the nightmare made me
Fuck,..Just had to be
Jump clear of the falling parts form me
How far did they go did they go
Can't give what you want from me baby
Tie me down
And try to take samples for examples
You could never see
Walk on me
But watch where you're stomping
Walk with caution
You couldn't comprehend
Step inside and see
Justify
You could never see my life is
You could never be my life is
You will never try my life is
Understanding me
Understanding me
What do you know about me
Am I alive
Can I see
What's happening around me
Put me down
Without even speaking
Forever thinking
You couldn't understand
Step inside and see
Compromise
You could never see my life is
You could never be my life is
You will never try my life is
Understanding me
Understanding me
Step inside and see
Good God
I've got your demon seed
Deep down inside of me
Two skins...One man
Fit in...One hand
God damn...That man
And everything created by him
Ask why...So high
Answer...Young die
Call scam...His hand
And everything created by them
I'm your man
By your hand
I'm your man
So look on,
I've got your demon seed
Deep down inside of me
So thin...Is this plan
Written in...Your hand
Watch me fall...My friend
As the bottom drops from beneath me
I'm your man
By your plan
I'm your riotous sin
So look on,
I've got your demon seed
Deep down inside of me
So look on, Fool of a golden deed
Deep down inside of me
So look on, look on
Can you tell me more
Have you ever been down this far before
Can you tell me more
Have you ever been down:
I'm two skins...I'm one man
I fit in...One hand
God damn...That hand
Honor - Choices that you make, reflect of whom you truly are
Courage - Rise above the masses, live your life complete and strong
Compassion - Is the power that must be used for the good of all
Loyal - To the ones in my care, standing true for what the cause
My soul has been searching, longing for something
I see my true self and I have learned well
Honesty - There are no shades of grey, only truth as it can be
Sincere - Don't need to give my word, to speak of such, is the same thing
Courtesy - There's no need to prove strength, even respect your enemies
Values - This is the code I feel, emotions without words, can speak
My soul has been searching, longing for something
I see my true self and I have learned well
My true self
You had your chance, it's over, no more time
This is not even over, it blows my mind
Can't understand what's in your mind
I feel this deed within me, it's all inside
I sacrificed everything, now it's my time
Throw it away, you threw it away, it's gone forever
I don't know any other way to live my life
This is all I've ever wanted amd it's mine
Can't understand your mind, I don't understand
Can't understand what's in your mind
Throw it away, you threw it away, it's gone forever
You had your chance, you're done, now it's in my grasp
He, who hesitates, is lost and now I've got the upper hand
Throw it away, you threw it away, it's gone forever
You played that hand and folded, you let it go
I stepped in and kicked the door open, you can't stop us now
While catering perfection
The light never shined off you
And then again my friend it's always
Been you through and through
Your one...if you choose
Maybe two..still I lose
A cripple on a wire
Take a look and see
Inside this prison called me
Scream aloud what you see
Turn me around again
My friend, my friend
If you see the fires burning my hands
I won't fly...cause when I reach the sky
I come tumbling down again
And I ....no I won't hide
I won't crawl to walk, to stand and fall again
So simple all the while
Way too simple for you
Tell me what to do
Do you want me to be like you
Build me up again
Stand me up to knock me down
Bloody hands mark where I've been
And my eyes could tell the stories
The fools that march beyond my grasp
Shame shame they oughta know better
A shining man I've never been
And the cloud around me knows better
Can't rhyme the reason
I've got the feeling once again
to kill again
I'm on my way
To kill aain
I've got the need to kill again
Sympathy isn't cheap
And no reason makes it bitter
The lines I hate dissipate
Form a crime against me you better
A shining man I've never been
And the cloud around me knows better
Can't face my opinion
I've got the feeling once again
To kill again
I'm on my way
To kill again
I've got the need to kill again
Seething the bleeding
Planting lifeless seeds of myself
Never a shining man never was never am
Never rising always falling
Planting all the seeds of myself
Fools say that I've lost my way
They say that from my path I've strayed away
Who'll clear my way to a better day
Who'll cleanse my veins and take all my pains away
She takes me in, She holds me in
She keeps me away from my sin
She makes me feel, Shemakes me real
She give me time to heal and
I never want to see the pain scar her fade again and
I never want to leave the warm embrace of my true friend
Sitting back I realize the mistakes I've made
Moving forward hope to find a simpler way
Feel as if the gods have damned my everyday
She takes me in, She holds me in
She keeps me away from my sin
She makes me feel, Shemakes me real
She give me time to heal and
I never want to see the pain scar her fade again and
Take a listen to your whole world
Can you hear the screams?
All alone i wonder
How much longer, is there time for me?
One last song
I want to give this world
Before it's gone
One last song
I don't think we learned a thing
Our history repeats
Will we heed these lessons?
Slit our throats and watch us bleed
Is there time for me?
One last song
I want to give this world
Before it's gone
One last song
Why can't we? When will we?
I don't think we want to learn
We won't be fucking happy
Until we destroy it all
One last song
I want to give this world
Before it's gone
God friend everybody's got a plan
An even eye can tell wrong from right
We just fade away
God damn tell me what's your plan
So, I will never stop to question why
Each and everyday
Heaven sent, ya need more
Hell's sure, I'm yours
Everybody's gotta rock right outta here
See the old faith, Feel the new faith
Everybody's gotta rock right outta here
See the old face, Know the real face
Feel the real faith
Fly high, Cut a dove in your brain
Exhale with the taste of everyday
We just fade away
Each and everyday
Scream loud with the pain of yesterday
Stand proud for yesterday has gone away
It just fades away
Heaven sent, ya need more
Hell's sure, I'm yours
I'd die, Ten Fold
Take your time take all your time baby
C'mon
Take your time take it anytime
Raise the line raise the line everytime
C'mon
Raise the line
Raise it above my mind
Everything that stains me and breaks me
It's just a gut reaction trapped in this aggressive action
I: Rise:
Everything is right here color me unsold
Everything is right here inside
Take the pain wash it all away baby
C'mon
Take the pain rip it all away
Take my hand take it anytime friend
C'mon
Take my hand take it anytime
Just like the king's men's nightmare
So low gotta see me to feel me
It's just a gut reaction
Trapped in this aggressive action
Everytime I give up something
I end up with less than mine
Turn around and see what's given
Sad the eyes
Distance is your best friend
At night it comes
Will they hear?
Being alone is what you want
It's the only way that you feel safe inside
The darkness that is me must try and heal
Please hear me
The pain that i feel
Happiness was nowhere to be found
Here I am
You hear nothing that i said
I showed the signs
Please hear me
Being alone is what I want
It's the only way that i feel safe inside
The darkness that is me must try and heal
Please hear me
The pain that I feel
Happiness was nowhere to be found
Please hear me
I scream out for help
We see you feelings running dry again
Who am I but a man that wants to die again
Felt fine till you opened up my sin
Sit back realize where we've been
We see you armies moving in again
A police action or genocide again
We see the past being hid again
Sit back realize where we've been
Frustrations seeping in again
We're trusting lies instead
Of the truth my friend
We see the blackness of your sins
Take a look back to where we've been
Our eyes read between your lines
Your actions are as loud as mime's
Red tape seals our lips again
Take a look back to where we've been
You make me want to stand up
And scream I want to be free
Never think about the unthinkable
Excuses they are what's giving
Of what's is ripe inside
And never ending
And they say
I move with the breeze if I can
Cause the grass won't grow where I stand
Knowing something if not everything
Stone the simple man
Laughter is something so they say
You can't fake dreams away
I move with the breeze if I can
Cause the grass won't grow where I stand
Knowing something if not everything
Stone the simple man
Make a mark on many at passing times
Take a power trip crazy within due style
Knowing something if not everything
Stone the simple man
Everything it leaves you something
And nothing starts the hunting
That's never ending
Gear are turning
In my head the sickness burning
Damning Eden
The purest of hearts are broken even
Ears are listening
The truth is sad a weak man's burden
Eyes are searching
The truth is sad it hides nothing
Touch my mind and fade away
Falling down... losing faith
You can't take my pain away
Falling down... Damning Eden
Hollowed sin
Dims the path of the righteous man
Hollowed man
Gear are turning
In my head the sickness burning
Damning Eden
The purest of hearts are broken even
Ears are listening
The truth is sad a weak man's burden
Eyes are searching
The truth is sad it hides nothing
Touch my mind and fade away
Falling down... losing faith
You can't take my pain away
Falling down... Damning Eden
Hollowed sin
Dims the path of the righteous man
Hollowed man
Show me the lines that bind inside
Tell me the lines that bind you...inside
High chairs creakin'
But the minds won't weaken
Soil in the pot
And then it's all fine here
Are all your wishes gone
Or is there one you hold dear
Too far to barrow
One of mine from over here
Say what am I...BUterrfly
Just a weed amongst flowers shining through
Butterfly..Saw what am I
Your minds been soaking in the bright blue sky
Rubber band-man
Can you really say you can
No way man
And then it's all fine here
Eyes show that you're the one that
I want to old near
Think of what you thought
Whoa, Black Betty (Bam-ba-Lam)
Whoa, Black Betty (Bam-ba-Lam)
Black Betty had a child (Bam-ba-Lam)
The damn thing gone wild (Bam-ba-Lam)
She said, "I'm worryin' outta mind" (Bam-ba-Lam)
The damn thing gone blind (Bam-ba-Lam)
I said Oh, Black Betty (Bam-ba-Lam)
Whoa, Black Betty (Bam-ba-Lam)
Whoa, Black Betty (Bam-ba-Lam)
Whoa, Black Betty (Bam-ba-Lam)
She really gets me high (Bam-ba-Lam)
You know that's no lie (Bam-ba-Lam)
She's so rock steady (Bam-ba-Lam)
And she's always ready (Bam-ba-Lam)
Whoa, Black Betty (Bam-ba-Lam)
Whoa, Black Betty (Bam-ba-Lam)
Whoa, Black Betty (Bam-ba-Lam)
Whoa, Black Betty (Bam-ba-Lam)
She's from Birmingham (Bam-ba-Lam)
Way down in Alabam' (Bam-ba-Lam)
Well, she's shakin' that thing (Bam-ba-Lam)
Boy, she makes me sing (Bam-ba-Lam)
Whoa, Black Betty (Bam-ba-Lam)
Whoa, Black Betty
BAM-BA-LAM
On and on you test your will
You've held on for this long
Don't want to die against your will
The choice is not your own
Every day you look at your sins
Once chance to wash them away
Every moment and everything
How precious life has become
This is the last chance
Your time is up and now you are free
Everything that you did
The memories are strong
All the lives that you touched
Embedded are my thoughts
Every day you look at your sins
Once chance to wash them away
Every moment and everything
How precious life has become
This is the last chance
Your time is up and now you are free
All your life
Had all the time
Thought you had the world
Felt this inside
Now you have died
We say goodbye to you
This is it you will be missed
And all you've done we won't forget it
Say goodbye, we say goodbye to you
This is the last chance
Your time is up and now you are free
This is it you will be missed
Lost your mind when I made you mine Now we see eye to eye
Rolled dead thoughts and smoked them blind
Still roll them and roll them still
I will consume you, I will soon own you
I am the prize in your game
The victor and loser too
Say you will, say you will
Say you'll always be there to hold me
Say you will, say you'll forgive me
Well I've got my thoughts inside you
The need to pull them through
You know I'll never hurt you
Yesterday but tomorrow will
I'm wrapped inside you, i'm wrapped around you
I am the disease in your veins
Yesterday and tomorrow still
I'll pick up all your pieces
Puzzle heart your missing 2
Force them into the wrong places
Act like you want me to
I'll let you meet all my faces
And yet hide the real me from you
I'll show you everything that I
Everything that I want me to
I am inside you, I am around you
I am the disease in your veins
One thing looking over my shoulder
Is the thought that it won't last
I got to give it this, it's moving fast
Better make a mark before it all pass
Whoever thought that they had doubts had better think again
You cannot begin to understand aal the things I am
That's for sure
If my world falls to pieces, will you still be there to pick me up?
I got respect for the people who listen
To the people who understand
The way I am and the way I act
This is my, there's no changing that
Whoever thought that they had doubts had better think again
You cannot begin to understand aal the things I am
That's for sure
If my world falls to pieces, will you still be there to pick me up?
Pick up the pieces of me
Pick up a piece
i spend my last days
withering away
don’t want to end like this
will you be my savior
and do this favor
i don’t want to win like this
will you just help me now
this is my last wish
let me go on to the end
can you place to rest
this is my last wish
today is a good day
go out my own way
do you understand
let me keep my honor
at this late hour
do you understand
will you just help me now
this is my last wish
let me go on to the end
can you place to rest
this is my last wish
i leave to you
i lay my last wish onto you
i leave it all to you
i leave it all to you
this is my last wish
let me go on to the end
can you place to rest
this is my last wish
this is my last wish
(this is my last wish)
let me go on to the end
can you place to rest
I am sickened by what I've heard
I can't believe the thing that you have done
To go this far nothing is unreal
It is a waste forever dead
This blood is on your hands
Now you're gone
You brought this upon yourself
And you will live forever, forever dead
You go and make all your choices
The path you choose, it can't and won't be won
Did you ever stop and think for a moment
That you will live forever dead
This blood is on your hands
Now you're gone
You brought this upon yourself
And you will live forever, forever dead
I'm sickened by what I've heard
I can't believe the thing that you have done
To go this far for nothing
It is a waste, forever dead
The blood is on your hands
Forver dead
Every day that goes by I think of this
We could not see the damage that was done
Another friend is lost, why is this?
It is a waste, forever dead
You brought this upon yourself
Look down at your hands
At the stake your about to drive
Feel the tears on your cheeks
Empty needle in your mind
Look into your blood red sky
Where your feeling fly so high
Every once in a while friend
Everyone needs a helping hand
Don't crucify me
I'm not ready to die just yet
I've got something to say, to see, to be
Crucified
Theive me one last chance
To prove what I can
Not made of brittle glass
Gut knotted, you don't care
Mind rotting, through my stare
You walk away
Lifeless feeling in my mind
Bloody hands seem so divine
You think it'll go away
Cross my heart, hope to die
I lost my dream today
I lost my dream today
I lost my....
Cross my heart, hope to die
Pluck out my f***ing eye
I am broken everywhere
Loveless bastard, I don't care
I walk away
Tell me something I don't know
Tell me how I need to grow
Emotions drain
(Dream today)
YOU, you walked away
YOU, never planned to stay
YOU, you walk away, just get away, just stay away
I said
YOU, never plan to stay, just walk away, just stay away
I swear
Cross my heart hope to die
Cross my heart hope to, dear god my,
Guts knotted, showed no care
Mind rotted through my stare
You walked away
Lifeless feeling everyday
Bloody hands were my decay
Well did you notice
What's wrong with me
No I can't even breathe
When my head's low
It's not with shame
It's from this pain you bring
Well I can feel it again
This loss is slowly crushing me
Through all this pain and suffering
I need you back in my arms
After all this pain and suffering
I want you back in my arms
Do you like my frown
I had a smile once
You turned it upside down
Make amends with me
No I can't even see
This broken day will come and go
Broken and battered with nothing to show
Could this be the better part of my life
Something to hold on to white knuckle tight
I wait for something
You gave me nothing
I wait for something real
Something real
In the air I hear the sound of your voice
Too many questions with no clear choice
On my mind are the clouds in your sky
Will they rain down on you the day that I shine
I'd get down on my knees
With open wrists begging please
Oh won't you be my angel of sweet nothing
All that was said about the feelings I've bled
I want to disappear
My peddled flower my finest hour I've
FIRST SIGHT
Turns me around again
Brings me face to face with my sin
I've got it, always had it
A reason to look within now
TAKE FLIGHT
To your sun again
Burns the sin straight from my hands
I've got it, always had it
A reason to live within now
Every time I fall
You catch me
And every time I lose control
You help me, you save me
And every time I lose myself
You find me, redefine me
MY GOD
How stained my hands have been
Makes me sick from inside out again
I've got it, always had it
A reason to look within now
STAND CLOSE
To my side again
Never stuck a knife in my back, friend
I've got it, always had it
A reason to live within now
Somebody to make me feel whole again
(better)
Somebody to make me want to love again
(my life gets better)
Somebody to make me see the sun again
(my life gets better)
Somebody to hold me, hold me
Until this life feels better
Every time I fall
And every time I lose control
You help me, you save me
And every time I lose myself
You find me, redefine me
And every time I hate myself
You love me, forgive me
And every time I lose myself
Tell me does your pride bleed
When you see me succeed
Is that the gist of your story
Now you had best get used to it
Cause I ain't about to quit
And i'm just now getting started
Shame me, claim me or deceive me
You grow sick every time ou hear me say believe me
Every time I get one foot up
You want to tear it down
YOU DENY ME \ DECEIVER
Every time I get one foot up
You tear it down, knock it down, tear it down
BELIEVER \ DENY ME
I feel your hand on my throat
As well as the knife in my back
And the whole time you keep smiling
What is your reason for this
Why won't your hate just quit
Life would better if you weren't struggling
(BELIEVER)
What's wrong with your world
Doesn't taste the same as mine
Aren't the shades the same as mine
Pain, Agony, Regret, Fear
Just dreams whisked away, TAKEN AWAY
So now does your pride still bleed
Every time that I succeed
Now that you know that I'll keep trying
Can your weak mind digest
Life is so fragile
Like a trembling leaf
Time passes slower
With each day of misery
Things aren't so bad
Hey can you heal me
Hey, hey listen to me
Time fell down my crippled wall
And I get what I deserve
Hey, hey listen to me
Focus on your pain
Nothing else remains
How would you answer
If I did the same
Before I cut my skin
Why you build me up
Just to tear me down
Like a little used soul
Pitches straight to the ground
In this game
There's something I strive to be yet
I always fall in my shame
If you allow it in
Then the trip never ends
And what really could have been
In this life
There's something I've tried to be yet
It's fallen right out of reach
So you picked me up
On my feet again
And then again I'm the man I am
So you picked me up
On my feet again
Lost inside is the man I am
Time and lines again
I've tried so hard to be a man
Hello again sweet mother
Do you still love me the way you used to
So sorry I didn't turn out
The way you always wanted me to
Tell me your sick and tired
Sick and tired of the way I live my life
You could never understand me
If you could take my hand
Take a look from where I stand
Someday you just might understand...me
Hello again sweet mother
Do you still love me the way you used to
So sorry I didn't turn out
The way you always wanted me to
Hello again sweet mother
Turn me around...upside down again
You don't like my lots in this life
Or the decisions I've made in my time
Why's me being different make a difference to you...why
If I fell down sweet mother
Would you pick me up
Swirling sea of emptiness
Your world has made me a broken mess
How are we supposed to see
The pain that brings us to our knees
Feel the motion of the ocean
Just to see how the hate will flow
It is...Simple
Wide open let me show you more
In my home/Open wide, wide open
There is nothing I know
I'm open wide, wide open
Nothing can save my world
Nothing can share your world
Nothing can save our world
Got caught up in your madness
With every turn we end up less
See all the changing leaves
And how they change to what you please
Feel the motion of the ocean
Just to get a taste of pain
It is...Simple
Wide open let me show you more
This I know
Open wide, wide open
My feelings are cold
I'm open wide, wide open
Swirling sea of emptiness
I am your broken mess
Twisting for eternity
She's been twisting for you and me
Took a ride on your ocean
Just to get a taste of pain
Open wide/Open wide
You gotta believe me
You cannot deceive me
You gotta be everything I ever wanted
Will you stand bye me
See what I see
Will you be every little thing to me
Will you...See my
One life's...So righteous
When I...Feel my
True life's...So worthless
Why: Why do I feel this way and why:
You could never ask of me
You cannot count on me
You couldn't ever once rely on me
Still you stand by me
Stand what's in me
Can you feel every little thing to me
Why: Why do I feel this way and why:
Why: Why cant I speak my mind and why:
Can you hear my words
Can you feel me breathing
Can you tell I'm dying
WHY:Everybody falls gotta keep on climbing
WHY:Do I feel this
WHY:Gotta be my life gotta be the meaning
WHY:Do I feel this
Don't believe what they say
Or trust what you hear
If it ever crosses what you know about me
Take a piece from in me
Guard it with pure greed
How long have I been standing here my friend
Has it been so long
I've been spreading myself so thin
And I've been so wrong
I wanna be the one you run to
And I wanna be your only one
I wanna be the one you turn to
And I wanna be the one
Why did all the good times turn to sin
And has it been so long
I've been standing here in my footprints
And I am so wrong
You shine on me all the good times with you
Where all the smiles belong
You trust in me to save the last tear for you
Cause I've been so wrong
Hey now its been so long
Hey hey won't you believe in me
Hey now I've come so far
How now won't you believe in me
Frustrations...My aberrance
My time...In my life
I can't be what you see in me
Tell me what you want to be, and don't hide it from me
Tell me where you want to be, and I'll take you there
Tell me how you want to feel, don't keep it from me
Tell me how it outta be through more than a stare
Show me what you wanna be, don't hide it from me
Show me where you wanna be, and I'll take you there
Show me how you want to feel, don't keep it from me
Show me how it outta be through more than a stare
I just want to see you
And I just want to hear you
And I just need to feel you
So stand up
Tell me who you are
Tell me where you want to be
Tell me how you feel
Show me how it outta be
Take a little piece of me and hang it from the right tree
Share a little piece of me and I'll keep you as a part of me
You are my all
You are my everything
Feel my angst
Deep within me
Feed my strength
Your words are empty
Look inside and you will see
Break inside break inside
I am, My own
And that's something to me
I've grown, Too strong
To be under your feet
See the hands
That try to hold me
Read the past
I never was free
Deeds of shame
The world around me
Know my pain
Sit back bare your cross to me
Oh won't I listen
God damn have I burned my hands
On what's been missing
I feel,.. Unreal everytime I try and stop to feel
Pick me up my friend
Let me start again
You fucked with me
Behind this garden
Don't fuck with me
Long before I could even see
You're what was missing
Twisting deep inside of me
Forever missing the glistening
I feel,.. Unreal
Everytime I try and stop to feel
Pick me up my friend
Hold closed your hand
Can you see all the clear skin in front of me
Can you see can you see what you wanna see
Can you see there's a little spot of light in me
Can you see can you tell I'm fuct
Bleeding emotions
Bleed emotions
Sat back gave your soul to me
But did I listen
God damn did I burn my hands
On what was missing, the glistening
I feel,.. Unreal
Everytime I try and stop to feel
Pick me up my friend
Hold closed my hand
You fucked with me
Behind this garden
You fucked with me
Within this garden
Sitting back...behind a power desk Assuming control
Walls...with doors shut
Like a newly caged fool
Scream aloud...did you wish this life
Did your choice of cards unfold...NO
Tell me there's no more rebels here
In search of freedom your caught In a blinded stare
Tell me there's no more rebels here
search inside for a....friend
Building block...where we could stand
Was this in the name of your god
Now...have you forgot
How it feels to be so alive
Hey man..is your fave a friend
Is the rat race your in ever gonna end...NO
Tell me there's no more rebels here
In search of freedom you caught in a blinded stare
If you cut yourself will you...
Bleed from fear or bleed with pride
Gonna show the world ain't right
Stand up force the hand
Don't breathe the breath of the concrete...clave
Walls...within you live your lige
All felt is good here
All felt is just fine
Like a rapture waiting
To dine on the divine
It moves across me
And sets me free
Open, oh, so gently
Every time I scream, "Release"
I mean it, you know it
Every time I feel relief
I feel the day, Black 7
I feel the day, Black 7
Loss of time is felt here
Burning brick in my mind
Like a cancer growing
In the minds of the divine
It moves across me
And sets me free
Open, oh, so gently
Every time I scream, "Release"
I mean it, you know it
Every time I feel relief
I feel the day, Black 7
Every time I scream, "Release"
I mean it and you know it
Every time I feel relief
I feel the day, Black 7
Don't roll me over
Can't help these things I feel
Couldn't see them coming
But I've given into what is real
Extend what's been given
Take a taste of what's within
You cast me over
Yet I've risen and I am real
It moves across me
And sets me free
Open, oh, so gently
It moves across me
And sets me free
Every time I scream, "Release"
I mean it, you know it
Every time I feel relief
I feel the day, Black 7
Every time I scream, "Release"
I mean it and you know it
Every time I feel relief
I feel the day, Black 7
I am the little cracked mirror
I mean it, you know it
I mean it, you know it
I mean it, you know it
I am your little cracked mirror
I am yours, yours
I am yours, I am yours
I am the little cracked mirror
I am yours, yours
gone is all the hope it seems
i store away all my worthless dreams
it’s breaking me
the sadness it falls down like rain
there is nothing left but this pain
it’s pouring down on me
it’s nothing new to say
it’s tearing at me
and i can’t take this anymore
and i can’t erase this anymore
i hear you crying
i feel like dying
i want to travel back in time
a place of happiness i find
and bring it back to me
bottle up all the things I’ve learned
light the pictures watch them burn
and hold on to that dream
I’m tired of all the same
my life is wasting
and i can’t take this anymore
and i can’t erase this anymore
i hear you crying
i feel like dying
and i can’t take this anymore
and i can’t erase this anymore
i hear you crying
i feel like dying
(i feel like dying)
(i feel like dying)
gone is all the hope it seems
i store away my worthless dreams
it’s breaking me
gone is all the hope it seems
i store away my worthless dreams
it’s breaking
it’s breaking
and i can’t take this anymore
and i can’t erase this anymore
i hear you crying
i feel like dying
and i can’t take this anymore
and i can’t erase this anymore
i hear you crying
i feel like dying
i can’t take this
i can’t take this anymore
i can’t take this
I’m done chasing sorrow
i facing my fear
been searching for tomorrow
to find out who i am
my eyes are getting clearer
my heart is beating fast
i see into my future
what i found is way too sad
and it all turned into nothing
the years have fallen
where have i been
I’m caught up in the moment
and these are my wasted years
the years have fallen
where have i been
I’m caught up in the moment
and these are my wasted years
I’m through feeling guilty
I’m done with my past
i looked into the sunlight
i knew it couldn't last
my heart is beating fast know
i see through bloodshot eyes
been dreaming of the future
one thing i despise
i could always see this coming
the years have fallen
where have i been
I’m caught up in the moment
and these are my wasted years
the years have fallen
where have i been
I’m caught up in the moment
and these are my wasted years
the years have fallen
where have i been
I’m caught up in the moment
these are my wasted years
the years have fallen
where have i been
I’m caught up in the moment
these are my wasted years
It's been a long time
I'm home again
Nothing I remember is there
Will everything come back to me again?
I towed the line, I did my time, until it's over
I gave it all, I watched you fall, until the end
Everyone I know is gone from here
Please tell me where I've been
Now, everything ?
Come back tell me again
I towed the line, I did my time, until it's over
I gave it all, I watched you fall, until the end
Now I'm left without a home, theres nothing but sorrow
And I got no place to go
Memories are gone
I'm left without a home
I'm left all alone
Where are they? Only heaven knows
My memories are gone
I towed the line, I did my time, until it's over
When father time has closed my eyes
And i've said my final goodbyes
Out of sight when i'm out of your mind
Will you remember
My time is all I had to give
Weighed down by the life that I live
Could you, Should you, Would you remember
Will I live again?
When father time has closed my eyes
And i've said my final goodbyes
Out of sight when i'm out of your mind
Will you remember
Will you remember me
Will you forget me
Will you remember me
Will you hear me
My face painted with peace
My life embraced when you speak
Do you remember the child, boy, man
What's right is not what today brings
The sun rises but does not set
On our sweet memories now do you remember
When this world knocked me down
I stood my ground for another round
All the good times and every bad
And all the time between
My ears always listening
My soul inhaled when you breathe
Out of sight when i'm out of your mind
I will not leave you
I will remember you
I won't forget you
I will remember you
I won't, will you?
i took your hand
you slipped away from me
i understand
why you have to leave
I’m not alone i try
holding on for life
you can not hear my cries no more, no more
heaven took you far away from me
left me empty and alone
heaven took you far away from me
too far away for me to go
it’s getting late
I’m right here next to you
I’m glad i stayed
to see the last of you
I’m not alone i try
holding on for life
you can not hear my cries no more, no more
heaven took you far away from me
left me empty and alone
heaven took you far away from me
too far away for me to go
the last breath is fading from your lips now
the warmth is leaving from your hands
you’re slipping further away
slipping away
slipping far away
heaven took you far away from me
left me empty and alone
heaven took you far away from me
too far away for me to go
(too far away for me to go)
heaven took you far away from me
left me empty and alone
heaven took you far away from me
too far away for me to go
i took your hand
long is the road that i walk upon
heavy is the load that i bear
strong is the will that keeps me holding on
i won’t be the lesser man
i won’t be the one
the lesser man, the lesser man, the lesser
i won’t be the one
the lesser man, the lesser man, the lesser man
time is the price that you have to pay
lonely is the burden that you may have
brave is the one that keeps holding on
keeping the faith the best i can
i won’t be the one
the lesser man, the lesser man, the lesser
i won’t be the one
the lesser man, the lesser man
this is where i make my stand
the lesser man, the lesser man
i won’t be the one
the lesser man
trying it harder and harder and do it you understand
i won’t be, i won’t be the lesser man
the lesser man
you see I’m trying it harder and harder and do it you understand
i won’t be, i won’t be the lesser man
the lesser man
long is the road that i walk upon
heavy is the load that i bear
strong is my will it keeps me holding on
i won’t be the lesser man
i won’t
be the
lesser man, lesser man
i wont
be the
lesser man, the lesser man
i won’t be the one
the lesser man, the lesser man, the lesser
i won’t be the one
the lesser man, the lesser man
this is where i make my stand
the lesser man, the lesser man
i won’t be the one
Hello there can anyone hear me
Slipping through the crack
Just a lifeless messenger
Caught in a world of looking back
See how my winds are changing
watch proud shoulders slack
Is the now built of the past
With no importance I fall back
When I've got you by my side
I won't have to stand alone no
When I've got you by my side
These ways will shatter
The growing ways take us father
Than we ever cared to travel
And if we keep our eyes on the glory
We'll embrace the never forever
Can any matter, weigh any less
Like a medal worn on the chest
A simple memory serves me less
Feel me, Touch me, leave me to waste
Without even taking a taste
This square peg has found it's round hole
Something’s knocking at my door
will i have strength to ignore
my world has turned to black
and i must surrender
he said sign here on this line
make your mark your soul is mine
it is said and done
and i won’t remember
the devil is sitting on my shoulder
temptation is creeping in
a devils deal is that of your soul
the only price i have to give
around, its pulling me
around, i can’t fight it
around, it’s time for me to give
temptation is taking over
what did i just go and do
all the hell now put me through
i am too far gone
and no one can save me
the devil is sitting on my shoulder
temptation is creeping in
a devils deal is that of your soul
the only price i have to give
around, its pulling me
around, i can’t fight it
around, it’s time for me to give
temptation is taking over
around, its pulling me
around, i can’t fight it
around, it’s time for me to give
temptation is taking over
the devil is sitting on my shoulder
the devil is sitting on my shoulder
the devil is sitting on my shoulder
temptation is creeping
the devils deal is that of your soul
the only price i have to give
around, its pulling me
around, i can’t fight it
around, it’s time for me to give
temptation is taking over
around, its pulling me
around, i can’t fight it
around, it’s time for me to give
temptation is taking over
around
around
picture this
you're going down
i can not stop the fall
descending fast
and you hit the ground
is this the end for us all
no more will I feel this
it’s not impossible
too bad to those who risk
out on the miracle
down, down,
and were tearing
change the structure
we have been tearing it down
tearing it down
tear it down
and the feelings come
you felt for so long
you must get up
take another hit
it only makes you strong
no more will I feel this
it’s not impossible
too bad to those who risk
out on the miracle
down, down,
and were tearing
change the structure
we have been tearing it down, down
and were tearing
change the structure
we have been tearing it down
tearing it down
tearing it down
tearing it down
tear it down
now picture this
you’re going down
is this the end for us al
no more will i feel this
it’s not impossible
down, down,
and were tearing
change the structure
we have been tearing it down, down
and were tearing
change the structure
we have been tearing it down
were tearing
change the structure
we have been tearing it down
everything
is closing in
won’t this emptiness
it’s surrounding me
with everything i feel i just know
is changing me
yeah, and i feel surrounded
it doesn’t matter where i go
cause i just can’t sleep
without you here
i just wanted you to know
that you leave me weak
and i feel frail
im surrounded
memories
are finding me
all of these rusted chains are pulling me down
feels like it’s killing me
and i feel surrounded
it doesn’t matter where i go
cause i just can’t sleep
without you here
i just wanted you to know
that you leave me weak
and i feel frail
im surrounded
you know i feel surrounded
im calling my feelings again
they’re hanging out inside my head
it’s in there breathing out exhaust
the walls are closing in again
it doesn’t matter where i go
cause i just can’t sleep
without you here
i just wanted you to know
that you leave me weak
and i feel frail
it doesn’t matter where i go
‘cause i just can’t sleep
without you here
(it’s killing me)
i just wanted you to know
that you leave me weak
and i feel frail
Asphalt...
Burning under the wheels beneath me
My black sky's are crying
Multi-colored pain upon me
Arms are rising
Straight up from the bodies beneath
They've come to carry me away
To a little 'ol place where I feel safe
Father time...
As always he's ticking away
Keeps on stealing my life
Day be day
The crimes timing
Couldn't ever be better for me
Arms are rising
Straight up from the bodies beneath
They've come to carry me away
To a little 'ol place where I feel safe
Brother-man don't you understand
I'm gone
I'm gone...
Like the wind around your world
Blowing through your hate stained door
I'm the man, I'm the king, I'm the one that's pure inside
Everyday, everyway I smell of suicide
Bitter sins how they grow within, so you tell me it ain't right
I am all sins and you're my reason for life
I will stone you, stone you
Wrap my arms around you
I will stone you, stone you
My little Halo
I will stone you, stone you
Wrap my arms around you
And I will stone you, stone you
My little Halo
I'm the man, I'm the king, I'm the one, that's broken from giving
Everday,everyway I swear just one last try
Killing me with the death to be something that's so right
I am all sins my hands are scarred with time
I will stone you, stone you
Wrap my arms around you
And I will stone you, stone you
My little Halo
I will stone you, stone you
Wrap my arms around you
And I will stone you, stone you
My little Halo
Some leave me
Feel through my eyes
I'm the man with the rock in his hand
Got the rock in my hand gonna stone you stone you
I'm the man with the rock in his hand
Got the rock in my hand gonna stone you stone you
I'm the man with the rock in his hand
Got the rock in my hand gonna stone you stone you
I'm the man with the rock in his hand
Got the rock in my hand gonna stone you
Make a change, gotta rearrange
Idle minds,crushing time
I am all sins and you're my reason for life
I will stone you, stone you
Wrap my arms around you
And I will stone you,stone you
My little Halo
I will stone you, stone you
Wrap my arms around you
And I will stone you, stone you
My little Halo
I will stone you, stone you
Put my god damn arms around you
And I will stone you, stone you
My little Halo
I will stone you, stone you
Put my arms around you
I will stone you, stone you
My little Halo
You get in my space
You get in my way
I cant do nothing
Nothings wrong
Keep on pushing
Up in my face
I'm gonna leave ya
Face down in the dirt
First you said it
Dont think you get it
One more time i'll
Break you down
You came out of no where
You only got yourself to blame
I gave all the warnings
There's nothing left to offer
Give it up
I can not take it
You're bothering me
What's your problem
Just get lost
Insist on prying
Your gonna get hurt
One more word
I'll burst and I'll break your bones
I'm bleeding from my ears again
Listen to this shit I have
Bleeding from my ears again
Listen to this shit I have
Bleeding from my ears again
Bleeding from my ears
You came out of no where
You only got yourself to blame
I gave all the warnings
There's nothing left to offer
You'll get what you deserve
You'll get what you have earned
I gave all the warnings
Theres nothing left to offer
Dragging me down
I try to keep myself from sinking
Without a sound I scream in silence
I stop all breathing
You fight for it and live for it, then it lets you down
Fight for life and it's all i see
Fight for life until it's through with me
Chewing me up, engulfed in madness
Searching again
Meaning in life
I keep on searching further to no end
You fight for it and live for it, then it lets you down
Fight for life and it's all i see
Fight for life until it's through with me
You fight for life then it's through with you
Holding me back
I keep on fighting, for what reason?
Torturing me, what is the purpose?
My time has ended
You fight for it and live for it, then it lets you down
Fight for life and it's all i see
Falter
i haven’t rendered this to anyone before
the book is open
and its spilling on the floor
comes once again
I’m buried in sin
all hope is gone
falter
falling down again
falter
feeling down again
waves come crashing ever lasting
this amount of pain
forever changing, anticipating
the same mistakes I’ve made
it comes once again
I’m buried in sin
all hope is gone
falter
falling down again
falter
feeling down again
feeling down again
I’m feeling down again
falter
falling down again
falter
feeling down again
(I’m feeling down again)
falter
(I’m falling down)
falling down again
the day begins this morning
it starts all over again
this routine is getting boring
i can’t wait for it to end
it’s like a slap in the face
it’s something that wont erase
a part of me that i hate
and i hate and i wake
and i can not break it
i think I’m feeling sick
(every moment i)
i can’t believe this shit
every moment I’m awake
every moment I’m awake
every moment I’m awake
i spend too much time home thinking
i need to turn off my brain
I’m blind to my inner feelings
i don’t do that i want to blame
it’s like a slap in the face
it’s something that won’t erase
a part of me that i hate
and i hate and i wake
and i can not break it
i think I’m feeling sick
(every moment i)
i can’t believe this shit
every moment I’m awake
i want to break away
every moment I’m awake
every moment I’m awake
from the moment i wake
it’s all in my head its all in my head
every breath that i take
its’ all in my head it’s all in my head
every move that i make
it’s all in my head it’s all in my head
i think I’m feeling sick
(every moment i)
i can’t believe this shit
every moment I’m awake
i want to break away
every moment I’m
every moment I’m
"Keep your ear on the ground
The story is in the soil"
- it's in the soil
Keep your senses naked - open
Watch out for a sign
- outside
It's all on you
Don´t be washed away from the flood
- wash away the flood
See and wonder how it feels
- do you know how it feels?
Do you know how it feels
Do you know about me
Keep your ear on the ground
It's all in the soil
Do you find the time
To find your mind
Don´t believe in yourself
Don´t believe in me
Put your hands on the ground
Pick up a leaf of grass
Keep your mouth shut
Don´t turn your head away
Now put your hands on the ground
Pick up a leaf of grass
And listen to the sound
Soil means the beginning
Soil means the end
That is my departure and I'll arrive at soil homeland
Feeds my mind with wise words
I'm protected in their arms
It's always warm like ember's fire
Even death can do us part
What have I got to leave?
Just words, by will to you...
What have I got to leave?
Some words and some tunes...
What have I got to leave?
All my hidden grief...
Before I fall like a withered leaf...
A shape appearing from a daydream
A memory from a swoon
An ancient river of dignity bringing eternal calm very soon
A new bud of the old tree beats under dead bark
I've felt your rain on my face
So many times
And that stream seem to wet me more
The light can make it dry
I wish i'd lighted you!
The warmth can make my seeds inspired
A spark for you too!
A feeling from inside
I wish i'd lighted you!
I hope that let me smile a while
A spark for you too!
Even if I'm soaked and small
I long for wind out of this cold
I don't live to see the sun
To dry me up
A pile of dirt is my own corps
Nourished by my damp thoughts
The light can make it dry
I wish i'd lighted you!
The warmth can make my seeds inspired
A spark for you too!
A feeling from inside
I wish i'd lighted you!
I hope that let me smile a while
A spark for you too!
Even if im soaked and small
I long for wind out of this cold
I wish you'd reply my call, 'cause
All moisture makes me grow so old
The light can make it dry
I wish i'd lighted you!
The warmth can make my seeds inspired
A spark for you too!
A feeling from inside
I wish i'd lighted you!
I hope that let me smile a while
A spark for you too!
When the sun and wind return
Let's just hope it doesnt burn
I miss you, I miss you
Soil is a natural body that consists of layers (soil horizons), composed primarily of minerals, which differ from their parent materials in their texture, structure, consistency, color, chemical, biological and other physical characteristics.[1] The end result, soil, is the end product of the influence of the climate (temperature, precipitation), relief (slope), organisms (flora and fauna), parent materials (original minerals), temperature, and time. In engineering, soil is referred to as regolith, or loose rock material. Strictly speaking, soil is the depth of regolith that influences and has been influenced by plant roots and may range in depth from centimeters to many meters.
Soil is composed of particles of broken rock (materials) that have been altered by chemical and mechanical processes that include weathering, erosion and precipitation. Soil is altered from its parent material by the interactions between the lithosphere, hydrosphere, atmosphere, and biosphere.[2] It is a mixture of mineral and organic materials that are in solid, gaseous and aqueous states.[3][4] Soil is commonly referred to as earth or dirt; technically, the term dirt should be restricted to displaced soil.[5]
Soil forms a structure filled with pore spaces that can be thought of as a mixture of solids, water and air (gas).[6] Accordingly, soils are often treated as a three state system.[7] Most soils have a density between 1 and 2 g/cm³.[8] Little of the soil of planet Earth is older than the Tertiary and none older than the Pleistocene.[9]
On a volume basis a good quality soil is one that is 45% minerals (sand, silt, clay), 25% water, 25% air, and 5% organic material, both live and dead. The mineral and organic components are considered a constant while the percentages of water and air are the only variable parameters where the increase in one is balanced by the reduction in the other.
Given time, the simple mixture of sand, silt, and clay will evolve into a soil profile that consists of two or more layers called horizons that differ in one or more properties such as texture, structure, color, porosity, consistency, and reaction. The horizons differ greatly in thickness and generally lack sharp boundaries. Mature soil profiles in temperate regions may include three master horizons A, B and C. The A and B horizons are called the solum or “true soil” as most of the chemical and biological activity that has formed soil takes place in those two profiles.[10]
The pore space of soil is shared by gasses as well as water. The aeration of the soil influences the health of the soil's flora and fauna and the emission of greenhouse gasses.
Of all the factors that influence the evolution of soil, water is the most powerful due to its effect on the solution and precipitation of minerals, plant growth, the leaching of minerals from the soil profile and the transportation and deposition of the very materials of which a soil is composed.
Soil colloidal particles (clay and humus) behave as a repository of nutrients and moisture, and buffer the variations of soil solution ions. Their contributions to soil nutrition are out of proportion to their part of the soil. Colloids act to store nutrients that might be leached and to release those ions in response to soil pH.
Soil pH, a measure of the hydrogen ion (acid-forming) soil reactivity, is a function of the soil materials, precipitation level and plant root behavior. Soil pH affects the availability of nutrients.
Most nutrients, with the exception of the lack of nitrogen in desert soils, are present in the soil but may not be available due to high or low pH. Most nutrients originate from minerals, are stored in organic material both live and dead and on colloidal particles as ions. The action of microbes on organic matter and minerals may free nutrients for use, sequester them, or cause their loss from the soil by their volitalization to gasses. The majority of the nitrogen available in soils are the result of nitrogen fixation by bacteria.
The organic material of the soil has a powerful effect on its development, fertility and available moisture. Following water, organic material is next in importance to the formation and fertility of soil.
The history of the study of soil is intimately tied to our urgent need to provide food for ourselves and forage for our animals. Throughout history, civilizations have prospered or declined as a function of availability and productivity of their soils.
The Greek historian Xenophon (450-355 B.C.) is credited with being the first to expound upon the merits of green-manuring crops, "But then whatever weeds are upon the ground, being turned into earth, enrich the soil as much a dung."[11]
Columella’s Husbandry, circa 60 A.D. was used by 15 generations (450 years) of those encompassed by the Roman Empire until its collapse. From the fall of Rome to the French Revolution, knowledge of soil and agriculture was passed on from parent to child and as a result, crop yields were low. During the Dark Ages for Europe, Yahya Ibn_al-'Awwam’s handbook guided the people of North Africa, Spain and the Middle East with its emphasis on irrigation, a translation of which was finally carried to the southwest of the United States.
Jethro Tull, an English gentleman, introduced in 1701 an improved grain drill that systemized the planting of seed and invented a horse-drawn weed hoe, the two of which allowed fields once choked with weeds to be brought back to production and seed to be used more economically. Tull, however, also introduced the mistaken idea that manure introduced weed seeds, and that fields should be plowed in order to pulverize the soil and so release the locked up nutrients. His ideas were taken up and carried to their extremes in the 20th century, when farmers repeatedly plowed fields far beyond what was necessary to control weeds. During a period of drought, the repeated plowing resulted in the Dust Bowl in the prairie region of the Central United States and Canada.
The "two-course system" of a year of wheat followed by a year of fallow was replaced in the 18th century by the Norfolk four-course system, in which wheat was grown in the first year, turnips the second, followed by barley, clover and ryegrass together, in the third. The taller barley was harvested in the third year while the clover and ryegrass were grazed or cut for feed in the fourth. The turnips fed cattle and sheep in the winter. The fodder crops produced large supplies of animal manure, which returned nutrients to the soil.[12] By the mid-nineteenth century, the Norfolk four-course system was widely adopted throughout Europe.
Experiments into what made plants grow, first led to the idea that the ash left behind when plant matter was burnt was the essential element but overlooked the role of nitrogen, which is not left on the ground after combustion. Jan Baptist van Helmont thought he had proved water to be the essential element from his famous experiment with a willow tree grown in carefully controlled conditions in which only water was added, and after five years of growth was removed and weighed, roots and all, found to be 165 pounds. The oven-dried soil, originally 200 pounds, was again dried and weighed and found to have lost only two ounces, which van Helmont reasonably explained as experimental error and assumed that the soil had in fact lost nothing. As rain water was the only thing added by the experimenter, he concluded that water was the essential element in plant life. In fact the two ounces lost from the soil were the minerals taken up by the willow tree during its growth.
John Woodward experimented with various types of water ranging from clean to muddy and found muddy water the best, and so he concluded earthy matter was the essential element. Others concluded it was humus in the soil that passed some essence to the growing plant.
The French chemist Antoine Lavoisier showed that plants and animals must “combust” oxygen internally to live and was able to deduce that most of the 165-pound weight of van Helmont’s willow tree derived from air. Hence, the chemical basis of nutrients delivered to the soil in manure was emphasized and in the mid-19th century chemical fertilizers were used, but the dynamic interaction of soil and its life forms awaited discovery.
It was known that nitrogen was essential for growth and in 1880 the presence of Rhizobium bacteria in the roots of legumes explained the increase of nitrogen in soils so cultivated. The importance of life forms in soil was finally recognized.
Crop rotation, mechanization, chemical and natural fertilizers led to a doubling of wheat yields in western Europe between 1800 to 1900.[13]
Soil formation, or pedogenesis, is the combined effect of physical, chemical, biological, and anthropogenic processes on soil parent material. Soil genesis involves processes that develop layers or horizons in the soil profile. These processes involve additions, losses, transformations and translocations of material that compose the soil. Minerals derived from weathered rocks undergo changes that cause the formation of secondary minerals and other compounds that are variably soluble in water. These constituents are moved (translocated) from one area of the soil to other areas by water and animal activity. The alteration and movement of materials within soil causes the formation of distinctive soil horizons.
How the soil "life" cycle proceeds is influenced by at least five classic soil forming factors that are dynamically intertwined in shaping the way soil is developed: parent material, climate, topography (relief), organisms and the passage of time. When reordered to climate, relief, organisms, parent material and time they form the acronym CROPT.[14]
An example of soil development would begin with the weathering of lava flow bedrock which would produce the purely mineral-based parent material from which soils form. Soil development would proceed most rapidly from bare rock of recent flows in a warm climate, under heavy and frequent rainfall. In such a condition, plants become established very quickly on basaltic lava, even though there is very little organic material. The plants are supported by the porous rock as it is filled with nutrient-bearing water that carries dissolved minerals from rocks and guano. Crevasses and pockets, local topography of the rocks, would hold fine materials and harbor plant roots. The developing plant roots themselves are associated with mycorrhizal fungi[15] that gradually break up the porous lava, and by these means organic matter and a finer mineral soil accumulate with time.
The material from which soil forms is called parent material. Rock, whether its origin is igneous, sedimentary or metamorphic, is the source of all soil mineral materials. The formation of a soil is dependent on their transportation and deposition and the physical and the chemical weathering as original minerals are transformed into soil.
Typical soil mineral materials are:[16]
Parent materials may be classified according to how they came to be deposited in place. Residual materials are those that have been weathered in place from primary bedrock; transported material have been deposited by water, wind, ice or gravity; and cumulose material is organic matter developed and accumulated in place.
Residual soils are soils that develop from their underlying parent rocks and have the same general chemistry as their parent rocks. The soils found on mesas, plateaus and plains are residual soils but few other soils are residual. In the United States as little as three percent of the soils are residual soils.[17]
Most soils are not residual but derive from transported materials that have been moved many miles by wind, water, ice and gravity.[18]
Cumulose parent material originates from deposited organic material and includes peat and mucksoils and result from plant residues that have been preserved by the low oxygen content of a high water table.
The weathering of parent material takes the form of physical disintegrating and chemical decomposition and transformation.
Saprolite is a particular example of a residual soil formed from the transformation of granite, metamorphic and other types of bedrock into clay minerals. Often called "weathered granite", saprolite is the result of weathering processes that include: hydrolysis (the division of a mineral into acid and base pairs by the splitting of intervening water molecules), chelation from organic compounds, hydration (the solution of minerals in water with resulting cation, anion pairs), and physical processes that include freezing and thawing.[21] The mineralogical and chemical composition of the primary bedrock material, its physical features, including grain size and degree of consolidation, plus the rate and type of weathering, transforms the parent material into a different mineral. The texture, pH and mineral constituents of saprolite are inherited from its parent material.
Climate is the dominate factor in soil formation, and soils show the distinctive characteristics of the climate zones in which they form.[22] Mineral precipitation and temperature are the primary climate influences on soil formation.
The direct influence of climate include[23]:
Climate directly affects the rate of weathering and leaching. Soil is said to be formed when detectable layers of clays, organic colloids, carbonates, or soluble salts have been moved downward. Wind moves sand and smaller particles, especially in arid regions where there is little plant cover. The type and amount of precipitation influence soil formation by affecting the movement of ions and particles through the soil, and aid in the development of different soil profiles. Soil profiles are more distinct in wet and cool climates, where organic materials may accumulate, than those in wet, warm climates where organic materials are rapidly consumed. The effectiveness of water in weathering parent rock material depends on seasonal and daily temperature fluctuations. Cycles of freezing and thawing constitute an effective mechanism that breaks up rocks and other consolidated materials.
Climate indirectly influences soil formation by the effect of vegetation cover, biological activity, hence the rates of chemical reactions in the soil.
The topography or relief characterized by the inclination of the surface determines the rate of precipitation runoff and rate of formation and erosion of the surface soil profiles. Steep slopes allow rapid runoff and erosion of the top soil profiles and little mineral deposition in lower profiles. Depressions allow the accumulation of water, minerals and organic matter and in the extreme, the resulting soils will be saline marshes or peat bogs. Intermediate topography affords the best conditions for the formation of an agriculturally productive soil.
Plants, animals, fungi, bacteria and humans affect soil formation (see soil biomantle and stonelayer). Animals and micro-organisms mix soils as they form burrows and pores, allowing moisture and gases to move about. In the same way, plant roots open channels in soils. Plants with deep taproots can penetrate many meters through the different soil layers to bring up nutrients from deeper in the profile. Plants with fibrous roots that spread out near the soil surface have roots that are easily decomposed, adding organic matter. Micro-organisms, including fungi and bacteria, effect chemical exchanges between roots and soil and act as a reserve of nutrients. Humans can impact soil formation by removing vegetation cover with erosion as the result. They can also mix the different soil layers, restarting the soil formation process as less weathered material is mixed with the more developed upper layers. Some soils may contain up to one million species of microbes per gram (most of those species being unknown), making soil the most abundant ecosystem on Earth.[24]
Vegetation impacts soils in numerous ways. It can prevent erosion caused by excessive rain and the resulting surface runoff. Plants shade soils, keeping them cooler and slowing evaporation of soil moisture, or conversely, by way of transpiration, plants can cause soils to lose moisture. Plants can form new chemicals that can break down minerals and improve soil structure. The type and amount of vegetation depends on climate, land form topography, soil characteristics, and biological factors. Soil factors such as density, depth, chemistry, pH, temperature and moisture greatly affect the type of plants that can grow in a given location. Dead plants and fallen leaves and stems begin their decomposition on the surface. There, organisms feed on them and mix the organic material with the upper soil layers; these added organic compounds become part of the soil formation process.
Time is a factor in the interactions of all the above. Over time, soils evolve features dependent on the other forming factors. Soil formation is a time-responsive process that is dependent on how the other factors interplay with each other. Soil is always changing. It takes about 800 to 1000 years for a 2.5 cm thick layer of fertile soil to be formed in nature. For example, recently deposited material from a flood exhibits no soil development because there has not been enough time for the material to form a structure that further defines soil. The original soil surface is buried, and the formation process must begin anew for this deposit. Over a period of time from hundreds to thousands of years the soil will develop a profile that depends on the intensities of biota and climate. While soil can achieve relative stability of its properties for extended periods, the soil life cycle ultimately ends in soil conditions that leave it vulnerable to erosion. Despite the inevitability of soil retrogression and degradation, most soil cycles are long.
Soil-forming factors continue to affect soils during their existence, even on “stable” landscapes that are long-enduring, some for millions of years. Materials are deposited on top and materials are blown or washed from the surface. With additions, removals and alterations, soils are always subject to new conditions. Whether these are slow or rapid changes depend on climate, topography and biological activity.
The physical properties of soils, in their order of decreasing importance, are its texture, structure, density, porosity, consistency, temperature, color and resistivity. These determine the availability of oxygen in the soil and ability of water to infiltrate and be held in the soil. Soil texture is determined by the relative proportion of the three kinds of soil particles, called soil "separates": sand, silt and clay. Larger soil structures are created from the separates when iron oxides, carbonates, clay and silica with the organic constituent humus, coat particles and cause them to adhere into relatively stable secondary structures called "peds". Soil density, particularly bulk density, is a measure of the soil compaction. Soil porosity consists of the part of the volume occupied by air and water. Consistency is the ability of soil to stick together. Soil temperature and color are self defining. Resistivity refers to the resistance to conduction of electric currents and affects the rate of corrosion of metal structures and concrete. Soil properties may change through the depth of a particular soil profile with each identifiable layer in the profile.
The mineral components of soil, sand, silt and clay determine a soils texture. In the illustrated textural classification triangle the only soil that does not exhibit one of those predominately is called "loam." While even pure sand, silt or clay may be considered a soil, from the perspective of food production a loam soil with a small amount of organic material is considered ideal. The mineral constituents of a loam soil might be 40% sand, 40% silt and the balance 20% clay by weight. Soil texture affects soil behavior, in particular its retention capacity for nutrients and water.[25]
Sand and silt are the products of physical and chemical weathering, while clay is frequently the precipitated product of chemical weathering. Clay on the other hand is a product of chemical weathering and often forms as a secondary mineral from dissolved minerals that precipitate from solution. It is the specific surface area of soil particles and the unbalanced ionic charges within them that determine their role in the cation exchange potential of soil, hence its fertility. Sand is least active followed by silt; clay is the most active. Sand has its greatest benefit to soil by resisting compaction and increasing porosity. Silt, with its higher specific surface area, is more chemically active than sand, but the clay content, with its very high specific surface area and generally large number of negative charges, gives clay its great retention capacity for nutrients and water. Clay soils resist wind and water erosion better than silty and sandy soils, as the particles are bonded to each other.
Sand is the most stable of the mineral components of soil; it consists of rock fragments, primarily quartz particles, ranging in size from 2.0 mm to 0.05 mm. Sand is largely inert but plays an important part in holding open soil. Silt ranges in size from 0.05 mm to 0.002 mm. Silt is mineralogically like sand but is more active than sand due to its larger surface area. Clay is the most important component of mineral soil due to its net negative charge and ability to hold cations. Clay cannot be resolved by optical microscopes; it ranges in size from 0.002 mm or less.[26] In medium-textured soils, clay is often washed downward through the soil profile and accumulates in the subsoil.
Soil components larger than 2.0 mm are classed as rock and gravel and are removed before determining the percentages of the remaining components and the texture class of the soil but are included in the name. For example, a sandy loam soil with 20% gravel would be called gravely sandy loam.
When the organic component of a soil is substantial, the soil is called organic soil rather than mineral soil. A soil is called organic if:
The clumping of the soil textural components of sand, silt and clay forms aggregates and the further association of those aggregates into larger units forms soil structures called peds. The adhesion of those soil components by organic substances, iron oxides, carbonates, clays and silica, and by the breakage of those aggregates due to expansion-contraction, freezing-thawing, and wetting-drying cycles forms soil into distinct geometric forms. These peds evolve into units that may have various shapes, sizes and degrees of development.[28] A soil clod is not a ped but rather a mass of soil that results from mechanical disturbance. The soil structure affects aeration, water movement, conduction of heat, resistance to erosion and plant root growth. Water has the strongest effect on soil structure due to its solution and precipitation of minerals and its effect on plant growth.
Soil structure often gives clues to its texture, organic matter content, biological activity, past soil evolution, human use, and chemical and mineralogical conditions under which the soil formed. While texture, is defined by the mineral component of a soil and is an innate property of the soil and does not change with agricultural activities, soil structure can be improved or destroyed by our choice and timing of farming practices.
Soil Structural Classes:[29]
At the largest scale, the forces that shape a soil's structure result from swelling and shrinkage that initially tend to act horizontally, causing vertically oriented prismatic peds. Clayey soil will induce horizontal cracks reducing columns to blocky peds. Roots, rodents, worms and freezing-thawing further break the peds into a spherical shape.
At a smaller scale, plant roots extend into voids and remove water and cause the open spaces to increase, and further decrease physical aggregation size. At the same time roots, fungal hyphea and earthworms create microscopic tunnels that break up peds.
At an even lower scale, soil aggregation continues as bacteria and fungi exude sticky polysaccharides that bind soil into small peds. The addition of the raw organic matter that bacteria and fungi feed upon encourages the formation of this desirable soil structure.
At the lowest scale, the soil chemistry affects the aggregation or dispersal of soil particles. The clay particles contain polyvalent cations that give faces of clay layers a net negative charge. At the same time the edges of the clay plates have a slight positive charge, thereby allowing the edges to adhere to the faces of other clay particles or to flocculate. On the other hand, when monovalent ions such as sodium invade and displace the polyvalent cations they weaken the positive charges on the edges, while the negative surface charges are relatively strengthened. This leaves a net negative charge on the clay, causing them to push apart, and so prevents the flocculation of clay particles into larger assemblages. As a result, the clay disperses and settles into voids between peds causing them to close. In this way the soil aggregation is destroyed and is made impenetrable to air and water. Such sodic soil tends to form columnar structures near the surface.[30]
Density is the weight per unit volume of an object. Particle density is the density of the mineral particles that make up a soil i.e. excluding pore space and organic material. Particle density averages approximately 2.65 g/cc (165 lbm/ft3). Soil bulk density, a dry weight, includes air space and organic materials of the soil volume. A high bulk density indicates either compaction of the soil or high sand content. The bulk density of cultivated loam is about 1.1 to 1.4 g/cc (for comparison water is 1.0 g/cc).[31] A lower bulk density by itself does not indicate suitability for plant growth due to the influence of soil texture and structure.
Soil treatment and identification | Bulk density g/cc | Pore space % |
---|---|---|
Tilled surface soil of a cotton field | 1.3 | 51 |
Trafficked inter-rows where wheels passed surface | 1.67 | 37 |
Traffic pan at 25 cm deep | 1.7 | 36 |
Undisturbed soil below traffic pan, clay loam | 1.5 | 43 |
Rocky silt loam soil under aspen forest | 1.62 | 40 |
Loamy sand surface soil | 1.5 | 43 |
Decomposed peat | 0.55 | 65 |
Pore space is that part of the bulk volume not occupied by either mineral or organic matter but is open space occupied by either air or water. Ideally, the total pore space should be 50% of the soil volume. The air space is needed to supply oxygen to organisms decomposing organic matter, humus and plant roots. Pore space also allows the movement and storage of water and dissolved nutrients.
There are four categories of pores:
In comparison, the root hairs are 8 to 12 microns in diameter. When pore space is less than 30 microns, the forces of attraction that hold water in place are greater than those acting to drain the water. At that point, soil becomes water logged and it cannot breathe. For a growing plant, pore size is of greater importance than total pore space. A medium textured loam provides the ideal balance of pore sizes. Having large pore spaces that allow rapid air and water movement is superior to smaller pore space but has a greater percentage pore space.[33] Tillage has the short term benefit of temporarily increasing the number of pores of largest size but in the end those will be degraded by the destruction of soil aggregation.[34]
Consistency is the ability of soil to stick together and resist fragmentation. It is of use in predicting cultivation problems and engineering of foundations. Consistency is measured at three moisture conditions: air-dry, moist and wet. The measures of consistency border on subjective as they employ the "feel" of the soil in those states. A soil's resistance to fragmentation and crumbling is made in the dry state by rubbing the sample. Its resistance to shearing forces is made in the moist state by thumb and finger pressure. Finally, a soils plasticity is measured in the wet state by molding with the hand.
The terms used to describe soil in those three moisture states and a last state of no agricultural value are as follows:
Soil consistency is useful in estimating the ability of soil to support buildings and roads. More precise measures of soil strength are often made prior to construction.
Soil temperature regulates germination, root growth and availability of nutrients. Soil temperatures range from permafrost at a few inches below the surface to 38 C (100 F) in Hawaii on a warm day. The color of the ground cover and insulating ability have a strong influence on soil temperature. Snow cover and heavy mulching will reflect light and slow the warming of the soil, but at the same time reduce the fluctuations in the surface temperature.
Below 50 cm (20 in), soil temperature seldom changes and can be approximated by adding 1.8 C (2 F) degrees to the mean annual air temperature
Most often, soil temperatures must be accepted and agricultural activities adapted to them to:
Otherwise soil temperatures can be raised by drying soils or using clear plastic mulches. Organic mulches slow the warming of the soil.
Soil color is often the first impression one has when viewing soil. Striking colors and contrasting patterns are especially noticeable. The Red River (Mississippi watershed) carries sediment eroded from extensive reddish soils like Port Silt Loam in Oklahoma. The Yellow River in China carries yellow sediment from eroding loess soils. Mollisols in the Great Plains are darkened and enriched by organic matter. Podsols in boreal forests have highly contrasting layers due to acidity and leaching.
In general, color is determined by organic matter content, drainage conditions, and the degree of oxidation. Soil color, while easily discerned, has little use in predicting soil characteristics.[35] It is of use in distinguishing boundaries within a soil profile, the origin of a soil's parent material, as an indication of wetness and waterlogged conditions, and as a qualitative means of measuring organic, salt and carbonate contents of soils. Color is recorded in the Munsell color system as for instance 10YR3/4.
Soil color is primarily influenced by soil mineralogy. Many soil colors are due to various iron minerals. The development and distribution of color in a soil profile result from chemical and biological weathering, especially redox reactions. As the primary minerals in soil parent material weather, the elements combine into new and colorful compounds. Iron forms secondary minerals with a yellow or red color, organic matter decomposes into black and brown compounds, and manganese, sulfur and nitrogen can form black mineral deposits. These pigments can produce various color patterns within a soil. Aerobic conditions produce uniform or gradual color changes, while reducing environments (anaerobic) result in disrupted color flow with complex, mottled patterns and points of color concentration.[36]
Soil resistivity is a measure of a soil's ability to retard the conduction of an electric current. The electrical resistivity of soil can affect the rate of galvanic corrosion of metallic structures in contact with the soil. Higher moisture content or increased electrolyte concentration can lower the resistivity and increase the conductivity thereby increasing the rate of corrosion.[37][38] Soil resistivity values typically range from about 2 to 1000 Ω·m, but more extreme values are not unusual.[39]
Water effects soil formation, structure, stability and erosion but is of primary concern with respect to plant growth. Water is essential to plants for four reasons:
In addition, water alters the soil profile by dissolving and redepositing minerals, often at lower levels, and possibly leaving the soil sterile in the case of extreme rainfall and drainage. In a loam soil, solids constitute half the volume, air one-quarter of the volume, and water one-quarter of the volume of which only half of that water will be available to most plants.
Water is retained in a soil when the adhesive force of attraction of water for soil particles and the cohesive forces water feels for itself are capable of resisting the force of gravity that tends to drain water from the soil. When a field is flooded, the air space is displaced by water. The field will drain under the force of gravity until it reaches what is called field capacity at which point the smallest pores are filled with water and the largest with water and air.[41] The total amount of water held when field capacity is reached is a function of the specific surface area of the soil particles. As a result, high clay and high organic soils have higher field capacities. The total force required to pull, or push water out of soil is given the term suction and usually expressed in units of bars (105 pascal) which is just a little less than one-atmosphere pressure. Alternatively, the terms tension or moisture potential may be used.[42]
The forces with which water is held in soils determines its availability to plants. Forces of adhesion hold water strongly to mineral and humus surfaces and less strongly to itself by cohesive forces. A plant's root may penetrate a very small volume of water that is adhering to soil and be able initially to draw water in that is only lightly held by the cohesive forces . But as the droplet is drawn down, the forces of adhesion of the water for the soil particles make reducing the volume of water increasingly difficult until the plant cannot produce sufficient suction to use the remaining water. The remaining water is considered unavailable. The amount of available water depends upon the soil texture and humus amounts and the type of plant. Cacti can for example, produce greater suction than can agricultural crop plants.
The following description applies to a loam soil and agricultural crops. When a field is flooded it is called saturated and all available air space is occupied by water. The suction required to draw water into a plant root is zero. As the field drains under the influence of gravity (drained water is called gravitational water or drain-able water), the suction required to be produced by the plant to use such water increases to 1/3 bar. At that point, the soil is said to have reached field capacity, and plants that use the water must produce increasingly higher suction, finally up to 15 bar. At 15 bar suction the soil water amount is called wilting percent. At that suction the plant cannot sustain its water needs as water is still being lost from the plant by transpiration; the plant's turgidity is lost, and it wilts. The next level, called air-dry, occurs at 1000 bar suction. Finally the oven dry condition is reached and at 10,000 bar suction. All water below wilting percentage is called unavailable water.[43]
The amount of water remaining in a soil drained to field capacity and the amount that is available is a function of the soil type. Sandy soil will retain very little water while clay will hold the maximum amount. The time required to drain a field from flooded condition for a clay loam that begins at 43% water by weight to a field capacity of 21.5% is six days whereas for a sand loam that is flooded to its maximum of 22% water, will take two days to reach field capacity of 11.3% water. The available water for the clay loam might be 11.3% whereas for the sand loam it might be only 7.9% by weight.[44]
Soil Texture | Wilting Point | Field Capacity | Available water capacity | |||
---|---|---|---|---|---|---|
Water per foot of soil depth | Water per foot of soil depth | Water per foot of soil depth | ||||
% | in. | % | in. | % | in. | |
Medium sand | 1.7 | 0.3 | 6.8 | 1.2 | 5.1 | 0.9 |
Fine sand | 2.3 | 0.4 | 8.5 | 1.5 | 6.2 | 1.1 |
Sandy loam | 3.4 | 0.6 | 11.3 | 2.0 | 7.9 | 1.4 |
Fine sandy loam | 4.5 | 0.8 | 14.7 | 2.6 | 10.2 | 1.8 |
Loam | 6.8 | 1.2 | 18.1 | 3.2 | 11.3 | 2.0 |
Silt loam | 7.9 | 1.4 | 19.8 | 3.5 | 11.9 | 2.1 |
Clay loam | 10.2 | 1.8 | 21.5 | 3.8 | 11.3 | 2.0 |
Clay | 14.7 | 2.6 | 22.6 | 4.0 | 7.9 | 1.4 |
The above are average values for the soil textures as the percentage of sand, silt, and clay vary within the listed soil textures.
Water moves through soil due to the force of gravity, osmosis and capillarity. At zero bar suction to one-third bar suction, water moves through soil due to gravity and is called saturated flow. At higher suction, water movement is called unsaturated flow.[46]
Water infiltration into soil is controlled by six factors:
Water infiltration rates range from 0.25 cm per hour for high clay soils to 2.5 cm per hour for sand, and well stabilized and aggregated soil structures.[48]
Once soil is completely wetted, any more water will move downward, or percolate, carrying with it clay, humus and nutrients, primarily cations, out of the range of plant roots and result in acid soil conditions. In order of decreasing solubility, the leached nutrients are:
In the United States percolation water due to rainfall ranges from zero inches just east of the Rocky Mountains to twenty or more inches in the Appalachian Mountains and the north coast of the Gulf of Mexico.[45]
At suctions less than one-third bar, water moves in all directions in unsaturated flow at a rate that is dependent on the square of the diameter of the water filled pores. Water is pushed by pressure gradients, from the point of its application where it is saturated locally, and pulled by capillary action due to adhesion force of water for the soil solids, producing a suction gradient from wet toward drier soil. Doubling the diameter of the pores increases the flow rate by a factor of four. Large pores drained by gravity and not filled with water do not greatly increase the flow rate for unsaturated flow. Water flow is primarily from coarse textured soil into fine-textured soil and moves most slowly through fine-textured soils such a clay.[50]
Of equal importance to the storage and movement of water in soil is the means by which plants acquire it and their nutrients. Ninety percent of water is taken up by plants as passive absorption caused by the pulling force of water evaporating (transpiring) from the long column of water that leads from its roots to its leaves. In addition, the high concentration of salts within the plant roots create an osmotic pressure gradient that pushes soil water into the roots. Osmotic absorption becomes more important during times of low water transpiration at night (lower temperatures) or due to high humidity during the day. It is the process which causes guttation.[51]
Root extension is vital for plant survival. A study of a single winter rye plant grown for four months in one cubic foot of loam soil showed that the plant developed 13,800,000 roots of 385 miles and 2,550 square feet of surface area and 14 billion hair roots of 6,600 miles and 4,320 square feet of root area, for a total surface area of 6,870 square feet. The total surface area of the loam soil was estimated to be 560,000 square feet.[52] In other words the roots were in contact with only 1.2% of the soil. Roots must seek out water as the unsaturated flow of water in soil can move only at a rate of up to 2.5 cm per day, as a result they are constantly dying and growing, as they seek out high concentrations of soil moisture.
Insufficient soil moisture to the point of wilting will cause permanent damage and crop yields will suffer. When grain sorghum was exposed to soil suction as low as 13.0 bar during the seed head emergence through bloom and seed set stages of growth, the production was reduced by 34%.[53]
Only a small fraction (0.1% to 1%) of the water used by a plant is held within the plant. Transpiration of water from the plant is the majority of water's use, while evaporation from the soil surface is also substantial. Transpiration plus evaporative soil moisture loss is called evapotranspiration. Evapotranspiration, plus water held in the plant totals to consumptive use which is nearly identical to evapotranspiration.[53]
The total water used in an agricultural field includes runoff, drainage, and consumptive use. The use of loose mulches will reduce evaporative losses for a period after a field is irrigated but in the end the total evaporative loss will approach that of an uncovered soil. The benefit from mulch is to keep the moisture available during the seedling stage. Water use efficiency is measured by transpiration ratio which is the ratio of the total water transpired by a plant to the dry weight of the harvested plant at a particular locale. Alfalfa may have a transpiration ratio of 500 (for a particular location) and as a result 500 kilograms of water will produce one kilogram of dry alfalfa. Transpiration ratios for crops range from 300 to 700.[54]
The atmosphere of soil is radically different from that of the atmosphere above. The consumption of oxygen by microbes and plant roots and their release of carbon dioxide decreases oxygen, and increases carbon dioxide concentration. Atmospheric CO2 concentration is 0.03% but in the soil pore space it may range from 10 to 100 times that level. In addition the void is saturated with water vapor. Adequate porosity is necessary not just to allow the penetration of water but also to allow gasses to diffuse in and out. Movement of gasses is by diffusion from high concentrations to lower. Oxygen diffuses in and is consumed and excess levels of carbon dioxide, which can become toxic, diffuse out with other gasses as well as water. Soil texture and its structure strongly affects soil porosity and gas diffusion.[55] Platy and compacted soils impede gas flow and a deficiency of oxygen may encourage anaerobic bacteria to reduce nitrate to N2, N2O, and NO, which is then lost to the atmosphere. Aerated soil is also a net sink of methane CH4 but a net producer of greenhouse gases when soils are depleted of oxygen and subject to elevated temperatures.[56]
The chemistry of soil determines the availability of nutrients, the health of microbial populations, and its physical properties. Soil chemistry determines its corrosivity, stability, and ability to absorb pollutants and to filter water. It is the surface chemistry of clays and humus colloids that determines soil's chemical properties. The very high specific surface area of colloids gives soil its great ability to hold and release cations in what is referred to as cation exchange. Cation exchange capacity is the amount of exchangeable cations per unit weight of dry soil and is expressed in terms of milliequivalents of hydrogen ion per 100 grams of soil. “A colloid is a small, insoluble, nondiffusible particle larger than a molecule but small enough to remain suspended in a fluid medium without settling. Most soils contain organic colloidal particles as well as the inorganic colloidal particles of clays.”[57]
Due to its high specific surface area, clay is the most active mineral component of soil. It is a colloidal and crystalline material. In soils, clay is defined in a physical sense as any mineral particle less that two microns in effective diameter. Chemically, clay is a range of minerals with certain reactive properties. Clay is also a soil textural class. Many soil minerals, such a gypsum, carbonates or quartz, are small enough to be classified physically as clay but they do not afford the same utility chemically as do clay minerals.[58]
Clay was once thought to be very small particles of quartz, feldspar, mica, hornblende or augite, but it is now known to be (with the exception of mica based clays) a precipitate with a mineralogical composition different from its parent materials and is classed as a secondary mineral. The type of clay that is formed is a function of the parent material and the composition of the minerals in solution. Mica based clays result from a modification of the primary mica mineral in such a way that it behaves and is classed as a clay. Most clays are crystalline but some are amorphous. The clays of soil are a mixture of the various types of clay but one type predominates.
Most clays are crystalline and most are made up of three or four planes of oxygen held together by planes of aluminum and silicon by way of ionic bonds that together form a single layer of clay. It is the spacial arrangement of the oxygen atoms that determines clay's structure. Half of the weight of clay is oxygen but on a volume basis oxygen is ninety percent.[59] The layers of clay are sometimes held together through hydrogen bonds or potassium bridges and as a result are less swelling in the presence of water. Other clays layers are loosely attached and will swell greatly when water intervenes between the layers.
There are three groups of clays:
Alumino-silica clays are characterized by their regular crystalline structure. Oxygen in ionic bonds with silicon forms a tetrahedral coordination that in turn forms sheets of silica. Two sheets of silica are bonded together by a plane of aluminum that form an octahedral coordination, called alumina, with the oxygens of the silica sheet above and that below it. Hydroxyl ions (OH-) sometimes substitute for oxygen. As much as one fourth of the aluminum Al3+ may be substituted by Zn2+, Mg2+ or Fe2+ and Si4+ may be substituted by Al3+. The substitution of lower valence ions for higher valence ions (isomorphic substitution) gives clay a net negative charge that attracts and holds cations some of which are of value for plant growth.
Amorphous clays are common in volcanic ash. They are mixtures of alumina and silica that have not formed the ordered crystal shape of alumino-silica clays that time would provide. The majority of their negative charges originates from hydroxyl ions which can gain or lose a hydrogen ion (H+) hence buffer soil pH. They may have either a negative charge provided by the attached hydroxyl ion (OH-), that can attract a cation, or lose the hydrogen of the hydroxyl to solution and display a positive charge that can attract anions. As a result they may display either high cation exchange capacity, in an acid soil solution, or high anion exchange capacity, in a basic soil solution.
Sesquioxide clays are a product of heavy rainfall, that has leached most of the silica and alumina from alumino-silica clay, leaving the less soluble oxides of iron Fe2O3 and iron hydroxide (Fe(OH)3) and aluminum hydroxides (Al(OH)3). Sesqi is Latin meaning one and one-half; there are three parts oxygen to two parts iron or aluminum, hence the ratio is one and one-half. They are hydrated and act as either amorphous or crystalline. It takes hundreds of thousands of years of leaching to create sesquioxide clays. They are not sticky and do not swell and soils high in them behave much like sand and can rapidly absorb water. They are able to hold large quantities of phosphates. Sesquioxides have low cation exchange capacity.[61][62]
Humus is the penultimate state of decomposition of organic matter; while it may linger for a thousand years, on the larger scale of the age of the other soil components, it is temporary. It is composed of the very stable lignins (30%) and complex sugars (polyuronides, 30%). On a dry weight basis, the cation exchange capacity of humus is many times greater than that of clay. Plant roots also have cation exchange sites.
Cation exchange, between colloids and soil water, buffers (moderates) soil pH, alters soil structure, and purifies percolating water by adsorbing cations of all types, both useful and harmful.
The negative charges on a colloid particle makes it able to hold cations to its surface. The charges result from four sources.
Cations held to the negatively charged colloids resist being washed downward by water and out of reach of plants roots, thereby saving the fertility of soils in areas of moderate rainfall and low temperatures.
There is a hierarchy in the process of cation exchange on colloids as they differ in the strength of adsorption and their ability to replace one another. If present in equal amounts:
Al3+ replaces H+ replaces Ca2+ replaces Mg2+ replaces K+ same as NH4+ replaces Na+[57]
If one cation is added in large amounts it may replace another by the sheer force of it numbers (mass action). This is largely what occurs with the addition of fertilizer.
As the soil solution becomes more acidic, the other cations bound to colloids are pushed into solution. This is caused by the ionization of hydroxyl groups on the surface of soil colloids in what is describes as pH dependent charges. Unlike permanent charges developed by isomorphous substitution, pH-dependent charges are variable and increase with increasing pH.[64] As a result those cations can be made available to plants but also able to be leached from the soil, possibly making the soil less fertile. Plants will excrete H+ to the soil and to replace cations on the colloids, making the cations available to the plant.
Cation exchange capacity should be thought of as the soils ability to remove cations from the soil water solution and sequester those to be exchanged later as the plant roots release hydrogen ions to the solution. CEC is the amount of exchangeable hydrogen cation (H+) that will combine with 100 grams dry weight of soil and whose measure is one milliequivalents per 100 grams of soil (1 meq/100 g). Hydrogen ions have a single charge and one-thousandth of a gram of hydrogen ions per 100 grams dry soil gives a measure of one milliequivalent of hydrogen ion. Calcium with an atomic weight 40 times that of hydrogen and with a valence of two, converts to (40/2) x 1 milliequivalent = 20 milliequivalents of hydrogen ion per 100 grams of dry soil or 20 meq/100 g.[65] The modern measure of CEC is expressed as centimoles of positive charge per kilogram (cmol/kg), of oven dry soil.
Most of the soil's CEC occurs on clay and humus colloids and the lack of those in hot, humid, wet climates, due to leaching and decomposition respectively, explains the sterility of tropical soils.
Soil | State | CEC meq/100 g |
---|---|---|
Charlotte fine sand | Florida | 1.0 |
Ruston fine sandy loam | Texas | 1.9 |
Glouchester loam | New Jersey | 11.9 |
Grundy silt loam | Illinois | 26.3 |
Gleason clay loam | California | 31.6 |
Susquehanna clay loam | Alabama | 34.3 |
Davie mucky fine sand | Florida | 100.8 |
Sands | ------ | 1 - 5 |
Fine sandy loams | ------ | 5-10 |
Loams and silt loams | ----- | 5-15 |
Clay loams | ----- | 15-30 |
Clays | ----- | over 30 |
Sesquioxides | ----- | 0-3 |
Kaolinite | ----- | 3-15 |
Illite | ----- | 25-40 |
Montmorillonite | ----- | 60-100 |
Vermiculite (similar to illite) | ----- | 80-150 |
Humus | ----- | 100-300 |
Anion exchange capacity should be thought of as the soils ability to remove anions from the soil water solution and sequester those for later exchange as the plant roots release carbonate anions to the solution. Those colloids that have low CEC tend to have some AEC. Amorphous and sesquioxide clays have the highest AEC followed by the iron oxides. The levels of AEC is much lower than for CEC. Phosphates tend to be held at anion exchange sites.
Iron and aluminum hydroxide clays are able to exchange their hydroxide anions (OH-) for other anions. The order reflecting the strength of anion adhesion is as follows:
H2PO4- replaces SO42- replaces NO3- replaces Cl-
The amount of exchangeable anions are of a magnitude of tenths to a few milliequivalents per 100 g dry soil.[67] As the pH rises there is more hydroxyls that will displace anions from the colloids and force them into solution and out of storage, hence the AEC decreases.
Soil reactivity is expressed in terms of pH and is a measure of the acidity and alkaninity of the soil. More precisely, it is a measure of hydrogen ion concentration in an aqueous solution and ranges in values from 0 to 14 (acidic to basic) but practically speaking for soils, pH ranges from 3.5 to 9.5 as pH values beyond those extremes are toxic to life forms.
At 25°C an aqueous solution that has a pH of 3.5 has 10-3.5 moles hydrogen ions per liter of solution (and also 10-10.5 mole/liter OH-) . A pH of 7, defined as neutral, has 10−7 moles hydrogen ions per liter of solution and also 10−7 moles of OH- per liter; since the two concentrations are equal they are said to neutralize each other. A pH of 9.5 is 10-9.5 moles hydrogen ions per liter of solution (and also 10-3.5 mole per liter OH-) . A pH of 3.5 has one million times more hydrogen ions per liter than a solution with pH of 9.5 (9.5 - 3.5 = 6 or 106) and is more acidic.[68]
Plants differ in their nutrient needs and the effect of pH is to remove from the soil or make available certain ions. High acid soils tend to have toxic amounts of aluminum and manganese. Plants that need calcium need moderate alkalinity but most minerals are more soluble in acid soils. Soil organisms are hindered by high acidity and most agricultural crops do best on mineral soils of pH 6.5 and organic soils of pH of 5.5.
In high rainfall areas, soils tend to acidity as the basic cations are leached away by rain allowing the soil colloids to become saturated with hydrogen ions from naturally acid rain leaving the soil sterile. The addition of any more hydrogen ions or aluminum hydroxyl cations drives the pH even lower as the soil is left with no buffering capacity. In low rainfall areas, unleached calcium pushes pH to 8.5 and with the addition of exchangeable sodium, soils may reach pH 10. Beyond a pH of 9 plant growth is reduced. High pH results in low micro-nutrient mobility, but water soluble-chelates of those can supply the deficit. Sodium can be reduced by the addition of gypsum (calcium-sulphate).
There are acid-forming cations (hydrogen and aluminum) and there are base-forming cations. The fraction of the base-forming cations that occupy positions on the soil colloids is called the base saturation percentage. If a soil has a CEC of 20 meq and 5 meq are aluminum and hydrogen cations (acid-forming) the remainder (20-5 = 15 meq) are assumed occupied by base-forming cations, then the percentage base saturation is 15/20 x 100% = 75 percent (the compliment 25% is assumed acid-forming cations). When the soil pH is 7 (neutral) base saturation is 100 percent and there are no hydrogen ions stored on the colloids. Base saturation is almost in direct proportion to pH and except for its use in calculating the amount of lime needed to neutralize an acid soil it is of little use.
The resistance of soil to changes in pH and available cations from the addition of acid or basic material is a measure of the buffering capacity of a soil and increases as the CEC increases. Hence, pure sand has almost no buffering ability. Buffering occurs by cation exchange and neutralization.
The addition of highly basic aqueous ammonia will cause the ammonium to displace hydrogen ions from the colloids and the end product is colloidally fixed ammonium and water, but no permanent change in pH.
The addition of lime, CaCO3, will displace hydrogen ions from the soil colloids, causing the fixation of calcium, the freeing of CO2 and leaving water, with no permanent change in pH.
The addition of carbonic acid (resulting from water and CO2) will displace calcium from colloids, thereby fixing hydrogen ions, evolving water and slightly alkaline (temporary increase in pH) highly soluble calcium bicarbonate, which will precipitate as lime (CaCO3) and water at a lower level in the soil. With the result of no permanent change in pH.
The general principal is that an increase in a particular cation in the soil water solution will cause that cation to be fixed to colloids (buffered) and a decrease in solution of that cation will cause it to be withdrawn from the colloid and moved into solution (buffered). The degree of buffering is limited by the CEC of the soil; the greater the CEC the greater the buffering capacity of the soil.
There are sixteen nutrients essential for plant growth and reproduction. They are carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, sulfur, calcium, magnesium, iron, boron, manganese, copper, zinc, molybdenum, and chlorine. Nearly all plant nutrients are taken up in ionic forms from the water part of the soil solution as cations or as anions. Plants release bicarbonate and hydorxyl (OH-) anions or hydrogen cations in an effort to cause nutrient ions to be freed from sequestration on colloids and so force them into the soil solution. Nitrogen ions and cations are stored in soil organic material and are made available to the plant roots by that material's decomposition by micro-organisms.[69]
Element | Symbol | Ion or molecule |
---|---|---|
Carbon | C | CO2 (mostly through leaves) |
Hydrogen | H | H+, HOH (water) |
Oxygen | O | O2-, OH -, CO32-, SO42-, CO2 |
Phosphorus | P | H2PO4 -, HPO42- (phosphates) |
Potassium | K | K+ |
Nitrogen | N | NH4+, NO3 - (ammonium, nitrate) |
Sulfur | S | SO42- |
Calcium | Ca | Ca2+ |
Iron | Fe | Fe2+, Fe3+ (ferrous, ferric) |
Magnesium | Mg | Mg2+ |
Boron | B | H3BO3, H2BO3 -, B(OH)4 - |
Manganese | Mn | Mn2+ |
Copper | Cu | Cu2+ |
Zinc | Zn | Zn2+ |
Molybdenum | Mo | MoO42- (molybdate) |
Chlorine | Cl | Cl - (chloride) |
All the nutrients with the exception of carbon are taken up by the plant through its roots. All those taken through the roots, with the exception of hydrogen which is derived from water, are taken up in the form ions. Carbon, in the form of carbon dioxide, enters primarily through the stomata of the leaves and where the plant releases oxygen as a byproduct of photosynthesis. All the hydrogen utilized by the plant originates from soil water and results in the release of further oxygen. Plants may have their nutrient needs supplemented by spraying a water solution of nutrients on their leaves, but nutrients are typically received through the roots by:
The nutrient needs of a plant may be carried to the plant by the movement the soil solution of water in a what is called mass flow. The absorption of nutrients by the roots from the water with which it is in contact, causes the concentration of nutrients in that area to be depleted. Nutrients then diffuse from areas with higher concentration to lower concentration, thereby bringing more nutrients near the roots. Plants also send out roots constantly to seek new sources of nutrients in a process called root interception. Meanwhile older less effective roots die back. Water is lifted to the leaves where it is lost by transpiration and in the process, it brings with it soil nutrients. A corn plant will use one quart of water per day at the height of its growing season.[71]
Nutrient | Approximate percentage supplied by: | ||
---|---|---|---|
Mass flow | Root interception | Diffusion | |
Nitrogen | 98.8 | 1.2 | 0 |
Phosphorus | 6.3 | 2.8 | 90.9 |
Potassium | 20.0 | 2.3 | 77.7 |
Calcium | 71.4 | 28.6 | 0 |
Sulfur | 95.0 | 5.0 | 0 |
Molybdenum | 95.2 | 4.8 | 0 |
Plants move ions of out of their roots in proportion to the amount of nutrients they move in. Hydrogen H+ is exchanged for cations and carbonate, HCO3- and hydroxide OH- anions are exchanged for nutrient anions. Plants derive most of their anion nutrients from decomposing organic matter, which hold 95 percent of the nitrogen, 5 to 60 percent of the phosphorus and 80 percent of the sulfur. As plant roots remove nutrients from the soil water solution, nutrients are added as ions move off of clay and humus, are added from decomposition of soil minerals, and released by the decomposition of soil organic matter. Where crops are produced, the nutrients must be augmented by fertilizer or added organic matter.[73]
Plants obtain their carbon from atmospheric carbon dioxide. A plant's weight is forty-five percent carbon. Elementally, carbon is 50% of plant material. Plant residues have a carbon to nitrogen ratio (C/N) of 50:1. As the soil organic material is digested by arthropods, and micro-organisms the C/N decreases as the carbonaceous material is metabolized and carbon dioxide (CO2) byproduct is released and finds its way to the atmosphere. The nitrogen, however, is sequestered in the bodies of the live matter. Normal CO2 concentration in the atmosphere is 0.03% which is probably the factor limiting plant growth. In a field of corn on a still day during high light conditions of the growing season, the CO2 concentration drops very low but under such conditions the crop could use up to 20 times the normal concentration. The respiration of CO2 by soil micro-organisms decomposing soil organic matter, contribute an important amount of CO2 to the photo-synthesizing plants. Within the soil CO2 concentration is 10 to 100 times atmospheric but may rise to toxic levels if the soil porosity is low or impeded by a flooded condition.[74]
Nitrogen is the most critical element attained by plants from the soil and is a bottleneck in plant growth.[75] Plants can use the nitrogen as either the cation, ammonium, NH4+, or the anion nitrate, NO3-. Nitrogen is seldom missing in the soil but is in the form of raw organic material and cannot be used directly. Some micro-organisms are able to metabolize the organic matter and release ammonium in a process called mineralization. Others take free ammonium and oxidize it to nitrate. Particular bacteria are capable of metabolizing N2 into the form of nitrate, in a process called nitrogen fixation. Both ammonium and nitrate can be lost from the soil by incorporation into the microbes living cells and temporarily immobilized or sequestered. Nitrate may also be lost when bacteria metabolize it to the gasses N2, N2O and so escape to the atmosphere in a process called denitrification. Nitrogen may be leached from the soil if it is in the form of nitrate and lost as a ammonia due to a chemical reaction of ammonium with alkaline soil called volatilization. Nitrogen is added to soil by rainfall. Ammonium may also be sequestered in clay by fixation.[76][77]
In a process called mineralization, certain bacteria feed on organic matter, releasing ammonia (NH3) (which may be reduced to ammonium NH4+) and other nutrients. As long as the carbon to nitrogen ratio (C/N) in the soil is above 30:1 nitrogen will be in short supply and other bacteria will feed on the ammonium and incorporate its nitrogen into their cells. In that form the nitrogen is said to be immobilized. Later when such bacteria die they too are mineralized. If the C/N is less than 15, ammonia is freed to the soil where it may be used by plants or certain bacteria may oxidize it to nitrate in a process called nitrification. Bacteria may on average add 25 pounds nitrogen per acre, and in an unfertilized field, it is the most important source of usable nitrogen. In a soil with 5 percent organic matter perhaps 2 to 5 percent of that is released to the soil by such decomposition. It occurs fastest in warm, moist, well aerated soil. The mineralization of 3 percent of a soil that is 4 percent organic matter would release 120 pounds of nitrogen as ammonium per acre.[78]
In symbiotic fixation, Rhizobium bacteria, are capable of conversion of N2 to nitrate in the process of nitrogen fixation. They have a symbiotic relationship with host plants wherein they supply the host with nitrogen and the host provides the bacteria with nutrients and a safe environment. It is estimated that such symbiotic bacteria in the root nodules of legumes add 45 to 250 pounds of nitrogen per acre per year, which may be sufficient for the crop. Other free living nitrogen fixing bacteria and blue-green algae live independently in the soil and release nitrate, when their dead bodies are converted by way of mineralization.[79]
Some amount of usable nitrogen is fixed by lightning as nitric acid (HNO3). Ammonia, NH3, previously released from the soil or from combustion, and the nitric acid fall with precipitation in giving a total of amount of about five pounds nitrogen pounds per acre per year.[80]
When bacteria feed on soluble forms of nitrogen (ammonium and nitrite) they temporarily sequester that nitrogen in their own bodies in a process called immobilization. At a later time when those bacteria die, their nitrogen may be released as ammonium by the processes of mineralization.
Protein material is easily broken down but the rate of its decomposition is slowed by its attachment to the crystalline structure of clay and held between the clay layers. The layers are small enough that bacteria cannot enter. Some organisms can exude extracellular enzymes that can act on the sequestered proteins. However, those enzymes too may be trapped on the clay crystals.
Ammonium fixation occurs when ammonium replaces the potassium ions that normally exist between the layers of clay such as illite or montmorillonite. Only a small fraction of nitrogen is held this way[81]
Usable nitrogen may be lost from soils when in the form of nitrate, as it is easily leached. Further losses of nitrogen occur by denitrification, the process whereby soil bacteria convert nitrate, to nitrogen gas N2 or N2O. This occurs when poor soil aeration limits free oxygen, forcing bacteria to use the oxygen in nitrate for its respiratory process. Denitrification is increased when oxidizable organic material is available and when soils are warm and slightly acidic. Denitrification may vary throughout a soil as the aeration varies from place to place. The conversion of nitrate to gasses causes their loss to the atmosphere. Denitrification may cause the loss of 10 to 20 percent of the available nitrates within a day when conditions are favorable and the losses of up to 60 percent of applied nitrate as fertilizer.[82]
Ammonium volatilization occurs when ammonium reacts chemically with an alkaline soil, converting NH4+ to NH3. The application of ammonium fertilizer to such a field can result in volatilization losses as much as 30 percent.[83]
Phosphorus is the second most critical plant nutrient. The soil mineral apatite is the most common mineral source of phosphorus. While there is on average 1000 pounds of phosphorus per acre in the soil, it is generally in unavailable forms. The available portion of phosphorus is low as it is in the form of phosphates of low solubility. Total phosphorus is about 0.1 percent by weight of the soil but only one percent of that is available. Of the part available more than half comes from the mineralization of organic matter. Agricultural fields may need to be fertilized to make up for the phosphorus that has been removed in the crop.[84]
When phosphorus does form solubilized ions of H2PO4-, they rapidly form insoluble phosphates of calcium or hydrous oxides of iron and aluminum. Phosphorus is largely immobile in the soil and is not leached but actually builds up in the surface layer if not cropped. The application of soluble fertilizers to soils may result in zinc deficiencies as zinc phosphates form. Conversely, the application of zinc to soils may immobilize phosphorus as zinc phosphate. Lack of phosphorus may interfere with the normal opening of the plant leaf stomata resulting in plant temperatures 10 percent higher than normal. Phosphorus is most available when soil pH is 6.5 in mineral soils and 5.5 in organic soils.[83]
The amount of potassium in a soil May 80,000 lb per acre of which only 150 lbs or 2 percent is available for plant growth. When solubilized, half will be held as exchangeable cations on clay while the other half is in the soil water solution. Potassium fixation occurs when soils dry and the potassium is bonded between layers of clay. Under certain conditions, dependent on the soil texture, intensity of drying, and initial amount of exchangeable potassium, the fixed percentage may be as much as 90 percent within ten minutes. In soils low in clay, potassium may be leached.[85]
Calcium is 1 percent by weight of soils and is generally available but may be low as it is soluble and can be leached. It is generally available except in sandy and heavily leached soil or strongly acidic mineral soil. Calcium is supplied to the plant in the form of exchangeable ions and moderately soluble minerals. Calcium is more available on the soil colloids than is potassium because the common mineral, calcite CaCO3 is more soluble than potassium bearing minerals.[86]
Magnesium is central to chlorophyll and aids in the uptake of phosphorus. The amount of magnesium beyond the minimum amount for plant health is not sufficient for forage animals. Magnesium is generally available, but is missing from some soils along the Gulf and Atlantic coasts of the United States.[87]
Most sulfur is made available to plants, like phosphorus, by its release from decomposing organic matter.[87] Deficiencies may exist in some soils and if cropped sulfur need be added. A 15-ton crop of onions uses up to 19 pounds of sulfur and 4 tons of alfalfa uses 15 pounds per acre. Sulfur abundance varies with depth. In a sample of soils in Ohio, United States, the sulfur abundance varied with depths, 0-6 inches, 6-12 inches, 12-18 inches, 18-24 inches in the amounts: 1056, 830, 686, 528 pounds per acre respectively.
Micronutrients iron, manganese, zinc, copper, boron, chlorine, and molybdenum, refers to the plant needs not their abundance in soil, are required in very small amounts but are essential to plant health. They are generally available in the mineral component of the soil but the heavy application of phosphates can cause a deficiency in zinc and iron, by the formation of insoluble phosphates. Iron deficiency may result from excessive amounts of heavy metals or calcuium minerals (lime) in the soil. Excess amounts of soluble boron, molybdenum, and chloride are toxic.[88]
The organic soil matter includes all the dead plant material and all creatures live and dead. The living component of an acre of soil may contain 900 pounds of earthworms, 2400 pounds of fungi, 1500 pounds of bacteria, 133 pounds of protozoa, 890 pounds of arthropods and algae.[89]
Most living things in soils, including plants, insects, bacteria and fungi, are dependent on organic matter for nutrients and energy. Soils have varying organic compounds in varying degrees of decomposition. Organic matter holds soils open, allowing the infiltration air and water and may hold as much twice its weight in water. Many soils, including desert and rocky-gravel soils, have no or little organic matter. Soils that are all organic matter, such as peat (histosols), are infertile.[90] In its earliest stage of decomposition the original organic material is often called raw organic matter. The final stage of decomposition is called humus.
Humus refers to organic matter that has been decomposed by bacteria, fungi and protozoa to the final point where it is resistant to further breakdown. Humus usually constitutes only five percent of the soil or less by volume but it is an essential source of nutrients and adds important textural qualities to soil critical to soil health and plant growth. Humus also hold bits of un-decomposed organic matter which feed arthropods and worms that further improve the soil. Humus has high cation exchange capacity that on a dry weight basis is many times greater than clay colloids and acts as a buffer, like clay, against changes in pH.
Humic acids and fulvic acids are important constituents of humus that begin with undecomposed organic matter. After death, these plant residues begin to decay, resulting finally in the formation of humus. With decomposition, there is a reduction of water soluble constituents including cellulose and hemicellulose; as the residues are deposited and break down, humin, lignin and lignin complexes accumulate within the soil; as microorganisms live and feed on decaying plant matter, an increase in these proteins occurs.
Lignin is resistant to breakdown and accumulates within the soil; it also chemically reacts with amino acids which add to its resistance to decomposition, including enzymatic decomposition by microbes. Fats and waxes from plant matter have some resistance to decomposition and persist in soils for a while. Clay soils often have higher organic contents that persist longer than soils without clay as the organic molecules adhere to the clay they are stabilized. Proteins normally decompose readily, but when bound to clay particles they become more resistant to decomposition. Clay particles also absorb the enzymes that would normally break down proteins. The addition of organic matter to clay soils can render that organic matter and any added nutrients inaccessible to plants and microbes for many years, since they can bind so strongly to the clay. High soil tannin (polyphenol) content from plants can cause nitrogen to be sequestered in proteins or cause nitrogen immobilization, also making nitrogen unavailable to plants.[91][92]
Humus formation is a process dependent on the amount of plant material added each year and the type of base soil; both are affected by climate and the type of organisms present. Soils with humus can vary in nitrogen content but have 3 to 6 percent nitrogen typically; raw organic matter, as a reserve of nitrogen and phosphorus, is a vital component affecting soil fertility.[90] Humus also absorbs water, acting as a moisture reserve that plants can utilize; it also expands and shrinks between dry and wet states, increasing soil porosity spaces. Humus is less stable than the soil's mineral constituents, as it is reduced by microbial decomposition, and over time its concentration diminshes without the addition of new organic matter. However, humus may persist over centuries if not millennia.
The production and accumulation or degradation of organic matter and humus is greatly dependent on climate. Temperature and soil moisture are the major factors in the formation or degradation of organic matter, they along with topography, determine the formation of organic soils. Organic matter tends to accumulate under wet or cold conditions where decomposer activity is impeded by low temperature[93] or excess moisture which results in anaerobic conditions.[94]
Horizontal layers of the soil, whose physical features, composition and age are distinct from the ones above and beneath, are referred to as soil horizons. The naming of horizons is based on the type of material of which they are composed; these materials reflect the duration of specific processes of soil formation. They are labeled using a short hand notation of letters and numbers[95] and are described and classified by their color, size, texture, structure, consistency, root quantity, pH, voids, boundary characteristics, and presence of nodules or concretions.[96] Few soil profiles have all the major horizons; soils may have one or many horizons.
The exposure of parent material to favorable conditions produces mineral soils that are marginally suitable for plant growth. Plant growth often results in the accumulation of organic residues. The accumulated organic layer called the O horizon produces a more active soil due to the effect of the organisms that live within it. Biological organisms colonize and break down organic materials, making available nutrients upon which other plants and animals can live. After sufficient time, humus moves downward and is deposited in a distinctive organic surface layer called the A horizon.
Soil is classified into categories in order to understand relationships between different soils and to determine the suitability of a soil for a particular use. One of the first classification systems was developed by the Russian scientist Dokuchaev around 1880. It was modified a number of times by American and European researchers, and developed into the system commonly used until the 1960s. It was based on the idea that soils have a particular morphology based on the materials and factors that form them. In the 1960s, a different classification system began to emerge, that focused on soil morphology instead of parental materials and soil-forming factors. Since then it has undergone further modifications. The World Reference Base for Soil Resources (WRB)[97] aims to establish an international reference base for soil classification.
A taxonomy is an arrangement in a systematic manner. Soil taxonomy has six categories. They are, from most general to specific: order, suborder, great group, subgroup, family and series. The soil properties that can be measured quantitatively are used to classify soils. A partial list is: depth, moisture, temperature, texture, structure, cation exchange capacity, base saturation, clay mineralogy, organic matter content and salt content.
In the United States, soil orders are the top hierarchical level of soil classification in the USDA soil taxonomy. the names of the orders end with the suffix -sol. There are 12 soil orders in Soil Taxonomy:[98] The criteria for the order divisions include properties that reflect major differences in the genesis of soils.
The percentages listed above[99] are for land area free of ice. "Soils of Mountains", which constitute the balance (11.6%), have a mixture of those listed above, or are classified as "Rugged Mountains" that have no soil.
The soil orders in sequence of increasing degree of development are Entisols, Inceptisols, Aridisols, Mollisols, Alfisols, Spodosols, Ultisols, and Oxisols. Histosols and Vertisols may appear in any of the above at any time during their development.
The soil suborders within an order are differentiated on the basis of soil properties and horizons that depend on soil moisture and temperature. Forty-seven suborders are recognized in the United States.
The soil great group category is a subdivision of a suborder. They distinguish one soil from another by the kind and sequence of soil horizons. About 185 great groups are recognized in the United States and are established on the basis of differentiating soil horizons and soil features. Horizons marked by clay, iron, humus and hard pans and soil features that are self-mixing such as clay, temperature, and marked quantities of various salts are used.
The great group categories are divided into three kinds of soil subgroups: typic, intergrade and extragrade. A typic subgroup represents the basic or "typical" concept of the great group to which the described subgroup belongs. An intergrade subgroup describes the properties that suggest how it grades (is similar to) toward soils of other soil great groups, suborders or orders. These properties are not developed or expressed well enough to include the described soil within the great group toward which they grade but suggest similarities. Extragrade features describes aberrant properties that prevent that soil from being included in another soil classification. There are about 1,000 subgroups in the United States.
A soil family category is a group of soils within a subgroup and describes the physical and chemical properties that affect the response of soil to agricultural management and engineering application. The principal characteristics used to differentiate soil families include texture, mineralogy, pH, permeability, structure, consistency, area's precipitation pattern, and soil temperature. For some soils the criteria also specify the percentage of silt, sand and coarse fragments such as gravel, cobbles and rocks. About 4,500 soil families are recognized in the United States.
A family may contain several soil series that describes the physical location by way of a name of a prominent physical feature such as a river, town, etc. near where the soil sample was taken. An example would be Merrimac for the Merrimac River in New Hampshire, USA. More than 14,000 soil series are recognized in the United States. This allows very specific descriptions to be made about soils.
Soil is used in agriculture, where it serves as the anchor and primary nutrient base for plants; however, as demonstrated by hydroponics, it is not essential to plant growth if the soil-contained nutrients could be dissolved in a solution. The types of soil and available moisture determine the species of plants that can be cultivated.
Soil material is a critical component in the mining and construction industries. Soil serves as a foundation for most construction projects. The movement of massive volumes of soil can be involved in surface mining, road building and dam construction. Earth sheltering is the architectural practice of using soil for external thermal mass against building walls.
Soil resources are critical to the environment, as well as to food and fiber production. Soil provides minerals and water to plants. Soil absorbs rainwater and releases it later, thus preventing floods and drought. Soil cleans the water as it percolates through it. Soil is the habitat for many organisms: the major part of known and unknown biodiversity is in the soil, in the form of invertebrates (earthworms, woodlice, millipedes, centipedes, snails, slugs, mites, springtails, enchytraeids, nematodes, protists), bacteria, archaea, fungi and algae; and most organisms living above ground have part of them (plants) or spend part of their life cycle (insects) belowground. Above-ground and below-ground biodiversities are tightly interconnected,[100][101] making soil protection of paramount importance for any restoration or conservation plan.
The biological component of soil is an extremely important carbon sink since about 57% of the biotic content is carbon. Even on desert crusts, cyanobacteria lichens and mosses capture and sequester a significant amount of carbon by photosynthesis. Poor farming and grazing methods have degraded soils and released much of this sequestered carbon to the atmosphere. Restoring the world's soils could offset some of the huge increase in greenhouse gases causing global warming while improving crop yields and reducing water needs.[102][103][104]
Waste management often has a soil component. Septic drain fields treat septic tank effluent using aerobic soil processes. Landfills use soil for daily cover. Land application of wastewater relies on soil biology to aerobically treat BOD.
Organic soils, especially peat, serve as a significant fuel resource; but wide areas of peat production, such as sphagnum bogs, are now protected because of patrimonial interest.
Both animals and humans in many cultures occasionally consume soil. It has been shown that some monkeys consume soil, together with their preferred food (tree foliage and fruits), in order to alleviate tannin toxicity.[105][1]
Soils filter and purify water and affect its chemistry. Rain water and pooled water from ponds, lakes and rivers percolate through the soil horizons and the upper rock strata, thus becoming groundwater. Pests (viruses) and pollutants, such as persistent organic pollutants (chlorinated pesticides, polychlorinated biphenyls), oils (hydrocarbons), heavy metals (lead, zinc, cadmium), and excess nutrients (nitrates, sulfates, phosphates) are filtered out by the soil.[106] Soil organisms metabolize them or immobilize them in their biomass and necromass,[107] thereby incorporating them into stable humus.[108] The physical integrity of soil is also a prerequisite for avoiding landslides in rugged landscapes.[109]
Here, land degradation[110] refers to human-induced or natural process which impairs the capacity of land to function. Soils are the critical component in land degradation when it involves acidification, contamination, desertification, erosion or salination.
While soil acidification of alkaline soils is beneficial, it degrades land when it lowers crop productivity and increases soil vulnerability to contamination and erosion. Soils are often initially acid because their parent materials were acid and initially low in the basic cations (calcium, magnesium, potassium and sodium). Acidification occurs when these elements are removed from the soil profile by normal rainfall, or the harvesting of forest or agricultural crops. Soil acidification is accelerated by the use of acid-forming nitrogenous fertilizers and by the effects of acid precipitation.
Soil contamination at low levels is often within soil's capacity to treat and assimilate. Many waste treatment processes rely on this treatment capacity. Exceeding treatment capacity can damage soil biota and limit soil function. Derelict soils occur where industrial contamination or other development activity damages the soil to such a degree that the land cannot be used safely or productively. Remediation of derelict soil uses principles of geology, physics, chemistry and biology to degrade, attenuate, isolate or remove soil contaminants to restore soil functions and values. Techniques include leaching, air sparging, chemical amendments, phytoremediation, bioremediation and natural attenuation.
Desertification is an environmental process of ecosystem degradation in arid and semi-arid regions, often caused by human activity. It is a common misconception that droughts cause desertification. Droughts are common in arid and semiarid lands. Well-managed lands can recover from drought when the rains return. Soil management tools include maintaining soil nutrient and organic matter levels, reduced tillage and increased cover. These practices help to control erosion and maintain productivity during periods when moisture is available. Continued land abuse during droughts, however, increases land degradation. Increased population and livestock pressure on marginal lands accelerates desertification.
Erosion of soil is caused by wind, water, ice and movement in response to gravity. Although the processes may be simultaneous, erosion is distinguished from weathering. Erosion is an intrinsic natural process, but in many places it is increased by human land use. Poor land use practices include deforestation, overgrazing and improper construction activity. Improved management can limit erosion by using techniques like limiting disturbance during construction, avoiding construction during erosion prone periods, intercepting runoff, terrace-building, use of erosion-suppressing cover materials, and planting trees or other soil binding plants.
A serious and long-running water erosion problem occurs in China, on the middle reaches of the Yellow River and the upper reaches of the Yangtze River. From the Yellow River, over 1.6-billion tons of sediment flow each year into the ocean. The sediment originates primarily from water erosion (gully erosion) in the Loess Plateau region of northwest China.
Soil piping is a particular form of soil erosion that occurs below the soil surface. It is associated with levee and dam failure, as well as sink hole formation. Turbulent flow removes soil starting from the mouth of the seep flow and subsoil erosion advances upgradient.[111] The term sand boil is used to describe the appearance of the discharging end of an active soil pipe.[112]
Soil salination is the accumulation of free salts to such an extent that it leads to degradation of the agricultural value of soils and vegetation. Consequences include corrosion damage, reduced plant growth, erosion due to loss of plant cover and soil structure, and water quality problems due to sedimentation. Salination occurs due to a combination of natural and human caused processes. Arid conditions favor salt accumulation. This is especially apparent when soil parent material is saline. Irrigation of arid lands is especially problematic.[113] All irrigation water has some level of salinity. Irrigation, especially when it involves leakage from canals and overirrigation in the field, often raises the underlying water table. Rapid salination occurs when the land surface is within the capillary fringe of saline groundwater. Soil salinity control involves watertable control and flushing with higher levels of applied water in combination with tile drainage or another form of subsurface drainage.[114][115]
Soil salinity models like SWAP,[116] DrainMod-S,[117] UnSatChem,[118] SaltMod[119][120] and SahysMod[121] are used to assess the cause of soil salination and to optimize the reclamation of irrigated saline soils.
Soils that contain high levels of particular clays, such as smectites, are often very fertile. For example, the smectite-rich clays of Thailand's Central Plains are among the most productive in the world.
Many farmers in tropical areas, however, struggle to retain organic matter in the soils they work. In recent years, for example, productivity has declined in the low-clay soils of northern Thailand. Farmers initially responded by adding organic matter from termite mounds, but this was unsustainable in the long-term. Scientists experimented with adding bentonite, one of the smectite family of clays, to the soil. In field trials, conducted by scientists from the International Water Management Institute in cooperation with Khon Kaen University and local farmers, this had the effect of helping retain water and nutrients. Supplementing the farmer's usual practice with a single application of 200 kg bentonite per rai (6.26 rai = 1 hectare) resulted in an average yield increase of 73%. More work showed that applying bentonite to degraded sandy soils reduced the risk of crop failure during drought years.
In 2008, three years after the initial trials, IWMI scientists conducted a survey among 250 farmers in northeast Thailand, half of whom had applied bentonite to their fields. The average improvement for those using the clay addition was 18% higher than for non-clay users. Using the clay had enabled some farmers to switch to growing vegetables, which need more fertile soil. This helped to increase their income. The researchers estimated that 200 farmers in northeast Thailand and 400 in Cambodia had adopted the use of clays, and that a further 20,000 farmers were introduced to the new technique.[122]
If the soil is too high in clay, adding gypsum, washed river sand and organic matter will balance the composition. Adding organic matter to soil that is depleted in nutrients and too high in sand will boost the quality.[123]
Wikiquote has a collection of quotations related to: Soil |
Wikimedia Commons has media related to: Soils |
|
|
|
|
|