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"Riparian" redirects here. For the legal doctrine, see "riparian water rights."

A well-preserved riparian strip on a tributary to Lake Erie.

A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the fifteen terrestrial biomes of the earth. Plant habitats and communities along the river margins and banks are called riparian vegetation, characterized by hydrophilic plants. Riparian zones are significant in ecology, environmental management, and civil engineering because of their role in soil conservation, their habitat biodiversity, and the influence they have on fauna and aquatic ecosystems, including grassland, woodland, wetland or even non-vegetative. In some regions the terms riparian woodland, riparian forest, riparian buffer zone, or riparian strip are used to characterize a riparian zone. The word "riparian" is derived from Latin ripa, meaning river bank.

Characteristics[link]

Riparian zones may be natural or engineered for soil stabilization or restoration. These zones are important natural biofilters, protecting aquatic environments from excessive sedimentation, polluted surface runoff and erosion. They supply shelter and food for many aquatic animals and shade that is an important part of stream temperature regulation. When riparian zones are damaged by construction, agriculture or silviculture, biological restoration can take place, usually by human intervention in erosion control and revegetation. If the area adjacent to a watercourse has standing water or saturated soil for as long as a season, it is normally termed a wetland because of its hydric soil characteristics. Because of their prominent role in supporting a diversity of species, riparian zones are often the subject of national protection in a Biodiversity Action Plan. These also known as a "Plant or Vegetation Waste Buffer".

Research shows riparian zones are instrumental in water quality improvement for both surface runoff and water flowing into streams through subsurface or groundwater flow. Particularly the attenuation of nitrate or denitrification of the nitrates from fertilizer in this buffer zone is important. Riparian zones can play a role in lowering nitrate contamination in surface runoff from agricultural fields, which runoff would otherwise damage ecosystems and human health. The use of wetland riparian zones shows a particularly high rate of removal of nitrate entering a stream and thus has a place in agricultural management.

Roles and functions[link]

Riparian zones dissipate stream energy. The meandering curves of a river, combined with vegetation and root systems, dissipate stream energy, which results in less soil erosion and a reduction in flood damage. Sediment is trapped, reducing suspended solids to create less turbid water, replenish soils, and build stream banks. Pollutants are filtered from surface runoff which enhances water quality via biofiltration.

The riparian zones also provide wildlife habitat, increase biodiversity, and provide wildlife corridors, enabling aquatic and riparian organisms to move along river systems avoiding isolated communities. They can provide forage for wildlife and livestock.

They provide native landscape irrigation by extending seasonal or perennial flows of water. Nutrients from terrestrial vegetation (e.g. plant litter and insect drop) is transferred to aquatic food webs. The vegetation surrounding the stream helps to shade the water, mitigating water temperature changes. The vegetation also contributes wood debris to streams which is important to maintaining geomorphology.

From a social aspect, riparian zones contribute to nearby property values through amenity and views, and they improve enjoyment for footpaths and bikeways through supporting foreshoreway networks. Space is created for riparian sports including fishing, swimming and launching for vessels and paddlecraft.

The riparian zone acts as a sacrificial erosion buffer to absorb impacts of factors including climate change, increased runoff from urbanisation and increased boatwake without damaging structures located behind a setback zone.

Role in logging[link]

The protection of riparian zones is often a consideration in logging operations. The undisturbed soil, soil cover, and vegetation provide shade, plant litter, woody material, and reduce the delivery of soil eroded from the harvested area. Factors such as soil types and root structures, climatic conditions and above ground vegetative cover impact the effectiveness of riparian buffering.

Vegetation[link]

Riparian zone along Trout Creek in the Trout Creek Mountains; part of the Burns Bureau of Land Management District in southeastern Oregon. The creek provides critical habitat for trout.

The assortment of riparian zone trees varies from those of wetlands and typically consists of plants that either are emergent aquatic plants, or herbs, trees and shrubs that thrive in proximity to water.

North America[link]

Water's edge[link]

Herbaceous Perennial:

• Peltandra virginica - Arrow Arum
• Sagittaria lancifolia - Arrowhead
• Carex stricta - Tussock Sedge
• Iris virginica - Southern Blue Flag Iris

Inundated Riparian zone[link]

Herbaceous Perennial:^[1]

• Sagittaria latifolia - Duck Potato
• Scirpus validus - Softstem Bulrush
• Scorpus americanus - Three-square Bulrush
• Eleocharis quadrangulata - Square-stem Spikerush
• Eleocharis obusa - Spikerush

Western[link]

In western North America and the Pacific Coast the riparian vegetation includes: Riparian trees^[2]

• Sequoia sempervirens - Coast Redwood
• Thuja plicata - Western Redcedar
• Abies grandis - Grand Fir
• Picea sitchensis - Sitka Spruce
• Chamaecyparis lawsoniana - Port Orford-cedar
• Taxus brevifolia - Pacific Yew
• Populus fremontii - Fremont Cottonwood
• Populus trichocarpa - Black Cottonwood
• Platanus racemosa - California Sycamore
• Alnus rhombifolia - White Alder
• Alnus rubra - Red Alder
• Acer macrophyllum - Big-leaf Maple
• Fraxinus latifolia - Oregon ash
• Prunus emarginata - Bitter Cherry
• Salix lasiolepis - Arroyo Willow
• Salix lucida - Pacific Willow
• Quercus agrifolia - Coast live oak
• Quercus garryana - Garry oak
• Populus tremuloides - Quaking Aspen
• Umbellularia californica - California Bay Laurel
• Cornus nuttallii - Pacific Dogwood

Riparian shrubs^[2]

• Acer circinatum - Vine Maple
• Ribes spp. - Gooseberies and Currants
• Rosa pisocarpa - Swamp Rose or Cluster Rose
• Symphoricarpos albus - Snowberry
• Spirea douglasii - Douglas spirea
• Rubus spp. - Blackberries, Raspberries, Thimbleberry, Salmonberry
• Rhododendron occidentale - Western Azalea
• Oplopanax horridus - Devil's Club
• Oemleria cerasiformis - Indian Plum, Osoberry
• Lonicera involucrata - Twinberry
• Cornus stolonifera - Red-osier Dogwood
• Salix spp. - Willows

Other plants

• Polypodium - Polypody Ferns
• Polystichum - Sword Ferns
• Woodwardia - Giant Chain Ferns
• Pteridium - Goldback Ferns
• Dryopteris - Wood Ferns
• Adiantum - Maidenhair Ferns
• Carex spp. - Sedges
• Juncus spp. - Rushes
• Festuca californica - California Fescue bunchgrass
• Leymus condensatus - Giant Wildrye bunchgrass
• Melica californica - California Melic bunchgrass
• Mimulus spp. - Monkeyflower and varieties
• Aquilegia spp. - Columbine

Asia[link]

In Asia there are different types of riparian vegetation, but the interactions between hydrology and ecology are similar as occurs in other geographic areas.^[3]

• Carex spp. - Sedges
• Juncus spp. - Rushes

Australia[link]

Typical riparian vegetation in Temperate New South Wales, Australia include:

• Acacia melanoxylon - Blackwood
• Acacia pravissima - Ovens Wattle
• Acacia rubida - Red Stem Wattle
• Bursaria lasiophylla - Blackthorn
• Callistemon citrinus - Crimson Bottlebrush
• Callistemon sieberi - River Bottlebrush
• Casuarina cunninghamiana - River She-Oak
• Eucalyptus bridgesiana - Apple Box
• Eucalyptus camaldulensis - River Red Gum
• Eucalyptus melliodora - Yellow Box
• Eucalyptus viminalis - Manna Gum
• Kunzea erocoides - Burgan
• Leptospernum obovatum - River Tea-Tree
• Melaleuca ericifolia - Swamp Paperbark

Central Europe[link]

Typical riparian zone trees in Central Europe include:

• Acer campestre - Field Maple
• Acer pseudoplatanus - Sycamore Maple
• Alnus glutinosa - Black Alder
• Carpinus betulus - European Hornbeam
• Fraxinus excelsior - European Ash
• Juglans regia - Persian Walnut
• Malus sylvestris - European Wild Apple
• Populus alba - White Poplar
• Populus nigra - Black Poplar
• Quercus robur - Pedunculate Oak
• Salix alba - White Willow
• Salix fragilis - Crack Willow
• Tilia cordata - Small-leaved Lime
• Ulmus laevis - European White Elm
• Ulmus minor - Field Elm

Repair and restoration[link]

Land clearing followed by floods can quickly erode a riverbank, taking valuable grasses and soils downstream, and allowing the sun to bake the land dry. Natural Sequence Farming techniques have been used in the Upper Hunter Valley of New South Wales, Australia to rapidly restore eroded farms to optimum productivity.^{[citation needed]}.

The Natural Sequence Farming technique involves placing obstacles in the water's pathway to lessen the energy of a flood, and help the water to deposit soil and seep into the flood zone. Another technique is to encourage fast growing plants such as "weeds" to grow, as these can quickly stabilize the soil, place carbon into the ground, and protect the land from drying. The weeds will improve the streambeds so that trees and grasses can return, and later replace the weeds.

Cottonwood Creek riparian area before restoration, 1988.	Cottonwood Creek riparian area after restoration, 2002.

See also[link]

	Environment portal
	Ecology portal
	Earth sciences portal
	Sustainable development portal

References[link]

Further reading[link]

• Nakasone, H., Kuroda, H., Kato, T. and Tabuchi, T. (2003). Nitrogen removal from water containing high nitrate nitrogen in a paddy field (wetland). Water Science and Technology, vol.48, no.10, pp. 209–216.
• Mengis, M., Schiff, S.L., Harris, M., English, M.C., Aravena, R., Elgood, R.J., and MacLean, A. (1999). Multiple geochemical and isotopic approaches for assessing ground water NO3 elimination in a riparian zone. Ground Water, 37, 448-457.
• Parkyn, Stephanie. (2004). Review of Riparian Buffer Zone Effectiveness. Ministry of Agriculture and Forestry (New Zealand), www.maf.govt.nz/publications.
• Tang, Changyuan; Azuma, Kazuaki; Iwami, Yoshifumi; Ohji, Baku; Sakura, Yasuo. (2004). Nitrate behaviour in the groundwater of a headwater wetland, Chiba, Japan. Hydrological Processes, vol.18, no.16, pp. 3159–3168.

External links[link]

Wikimedia Commons has media related to: Riparian forests

• Dissertation on riparian vegetation of chalakudy river
• Canadian Government site
• Restoration strategies for riparian habitats, US military
• Education and awareness site
• National Riparian Service Team, Bureau of Land Management
• Riparian Habitat Restoration in the Las Vegas Wash
• Red River Basin Riparian Project
• Riparian Forest Buffers, Kansas State University
• The short film Agroforestry Practices - Riparian Forest Buffers (2004) is available for free download at the Internet Archive [more]

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The Edge
Background information
Birth name	David Howell Evans
Born	(1961-08-08) 8 August 1961 (age 50) Barking, Essex, England, United Kingdom
Origin	County Dublin, Ireland
Genres	Rock, post-punk, alternative rock
Occupations	Musician, songwriter, activist
Instruments	Guitar, vocals, keyboards, piano, bass guitar
Years active	1976–present
Labels	Island, Mercury
Associated acts	U2, Passengers
Website	www.u2.com
Notable instruments
Gibson Explorer Fender Stratocaster Gibson Les Paul Fender Telecaster Gretsch Country Gentleman Gretsch White Falcon Rickenbacker 330/12

David Howell Evans (born 8 August 1961), more widely known by his stage name The Edge (or just Edge),^[1] is a musician best known as the guitarist, backing vocalist, and keyboardist of the Irish rock band U2. A member of the group since its inception, he has recorded 12 studio albums with the band and has released one solo record. As a guitarist, The Edge has crafted a minimalistic and textural style of playing. His use of a rhythmic delay effect yields a distinctive ambient, chiming sound that has become a signature of U2's music.

The Edge was born in England to a Welsh family, but was raised in Ireland after moving there as an infant. In 1976, at Mount Temple Comprehensive School, he formed U2 with his fellow students and his older brother Dik. Inspired by the ethos of punk rock and its basic arrangements, the group began to write its own material. They eventually became one of the most popular acts in popular music, with successful albums such as 1987's The Joshua Tree and 1991's Achtung Baby. Over the years, The Edge has experimented with various guitar effects and introduced influences from several genres of music into his own style, including American roots music, industrial music, and alternative rock. With U2, The Edge has also played keyboards, co-produced their 1993 record Zooropa, and occasionally contributed lyrics. The Edge met his second and current wife, Morleigh Steinberg, through her collaborations with the band.

As a member of U2 and as an individual, The Edge has campaigned for human rights and philanthropic causes. He co-founded Music Rising, a charity to support musicians affected by Hurricane Katrina. He has collaborated with U2 bandmate Bono on several projects, including songs for Roy Orbison and Tina Turner, and the soundtracks to the musical Spider-Man: Turn Off the Dark and the Royal Shakespeare Company's London stage adaptation of A Clockwork Orange. In 2011, Rolling Stone magazine placed him at number 38 on its list of "The 100 Greatest Guitarists of All Time".

Personal life[link]

The Edge at a U2 concert in Anaheim (2005)

David Howell Evans was born at the Barking Maternity Hospital,^[2] Essex, England to Welsh parents Garvin and Gwenda Evans.^[1] When he was one, his family moved to County Dublin, Ireland where he attended St Andrew's National School. He received piano and guitar lessons and often performed with his brother Dik Evans before they both answered an advertisement posted by Larry Mullen, Jr. at their school, Mount Temple Comprehensive School, seeking musicians to form a band.^[3] The band accepted both of them. This band went through several incarnations before emerging as U2 in March 1978 (Dik Evans left the band just before the name change).^[3] U2 began performing in various venues in Ireland and eventually began developing a following. Their debut album, Boy, was released in 1980.

In 1981, leading up to the October tour, Evans came very close to leaving U2 for religious reasons, but he decided to stay.^[3] During this period, he became involved with a group called Shalom Tigers, in which bandmates Bono and Larry Mullen Jr. were also involved.^[4] Shortly after deciding to remain with the band, he wrote a piece of music that later became "Sunday Bloody Sunday".^[3] The Edge married his high school girlfriend Aislinn O'Sullivan on 12 July 1983.^[5] The couple had three daughters together: Hollie in 1984, Arran in 1985 and Blue Angel in 1989.^[4] The couple separated in 1990, but were unable to get officially divorced because of Irish laws regarding marriage annulment; divorce was legalised in 1995 and the couple were legally divorced in 1996.^[4]

In 1993, The Edge began dating Morleigh Steinberg, a professional dancer and choreographer employed by the band as a belly dancer during the Zoo TV Tour. They had a daughter, Sian (born 1997), and a son, Levi (born 25 October 1999),^[4] before marrying on 22 June 2002.^[4] He appeared in the 2009 music documentary film It Might Get Loud.^[6] The Edge has been criticized for his efforts to build five luxury mansions on a 156 acre plot of land in Malibu, California.^[7] The California Coastal Commission voted 8-4 against the plans, with the project described by the commission's executive director, Peter Douglas, as "In 38 years...one of the three worst projects that I've seen in terms of environmental devastation...It's a contradiction in terms – you can't be serious about being an environmentalist and pick this location."^[7] The Santa Monica Mountains Conservancy agreed to remain neutral on the issue following a $1 million donation from The Edge and a commitment from The Edge to designate 100 acres of the land as open space for public footpaths.^[7]

Music style[link]

Guitar playing[link]

As a guitar player, The Edge has a sound typified by a low-key playing style, a chiming, shimmering sound (thanks in part to the sound of VOX AC-30s) that he achieves with extensive use of delay effects and reverb. The feedback delay is often set to a dotted eighth note (3/16 of a measure), and the feedback gain is adjusted until a note played repeats two or three times.^{[citation needed]}

On 1987's The Joshua Tree, The Edge often contributes just a few simple lead lines given depth and richness by an ever-present delay. For example, the introduction to "Where the Streets Have No Name" is simply a repeated six-note arpeggio, broadened by a modulated delay effect. The Edge has said that he views musical notes as "expensive", in that he prefers to play as few notes as possible. He said in 1982 of his style,

"I like a nice ringing sound on guitar, and most of my chords I find two strings and make them ring the same note, so it's almost like a 12-string sound. So for E I might play a B, E, E and B and make it ring. It works very well with the Gibson Explorer. It's funny because the bass end of the Explorer was so awful that I used to stay away from the low strings, and a lot of the chords I played were very trebly, on the first four, or even three strings. I discovered that through using this one area of the fretboard I was developing a very stylized way of doing something that someone else would play in a normal way."^[9]

Many different influences have shaped The Edge's guitar technique.^{[citation needed]} His first guitar was an old acoustic guitar that his mother bought him at a local flea market for only a few pounds; he was nine at the time. He and his brother Dik Evans both experimented with this instrument.^[9] He said in 1982 of this early experimentation, "I suppose the first link in the chain was a visit to the local jumble sale where I purchased a guitar for a pound. That was my first instrument. It was an acoustic guitar and me and my elder brother Dik both played it, plonking away, all very rudimentary stuff, open chords and all that."^[9] The Edge has stated that many of his guitar parts are based around guitar effects. This is especially true from the Achtung Baby era onwards, although much of the band's 1980s material made heavy use of echos.

Vocals[link]

The Edge in June 2005

The Edge also supplies the backing vocals for U2. U2's 1983 live album and video release, Under a Blood Red Sky and Live at Red Rocks: Under a Blood Red Sky are good reference points for his singing (as are the live DVDs from the Elevation Tour, U2 Go Home: Live from Slane Castle and Elevation 2001: Live from Boston). For example, he sings the chorus to "Sunday Bloody Sunday" (Bono harmonizes on the final 'Sunday'). U2 used this tradeoff technique later in "Bullet the Blue Sky" as well. His backing vocals are sometimes in the form of a repeated cry; examples of songs that use this approach include "Beautiful Day", "New Year's Day" and "Stay (Faraway, So Close!)". Another technique he uses in his backing vocals is the falsetto, in songs such as "Stuck in a Moment You Can't Get Out Of", "Sometimes You Can't Make It on Your Own", "A Man and a Woman", "The Wanderer", live versions of "The Fly", and "Window in the Skies".

The Edge sings the lead vocal on "Van Diemen's Land" and "Numb", the first half of the song "Seconds", dual vocals with Bono in "Discotheque", and the bridge in the song "Miracle Drug".^[4] He also sings the occasional lead vocal in live renditions of other songs (such as "Sunday Bloody Sunday" during the PopMart Tour and "Party Girl" during the Rotterdam Zoo TV show when it was Bono's birthday).^[10] He also plays a solo acoustic version of the song "Love is Blindness" that is featured in the documentary film From the Sky Down.

Other instruments[link]

He has played piano and keyboards on many of the band's songs, including "I Fall Down", "October", "So Cruel", "New Year's Day", "Running to Stand Still", "Miss Sarajevo", "The Hands that Built America", and "Original of the Species" and others. He plays the organ on "Please". In live versions of "New Year's Day", "The Unforgettable Fire", "Your Blue Room", and "Moment of Surrender", he plays both the piano and guitar parts alternately. In most live versions of "Original of the Species," piano is the only instrument played during the song. Although The Edge is the band's lead guitarist, he occasionally plays bass guitar, including the live performances of the song "40" where The Edge and bassist Adam Clayton switch instruments.

Solo recordings[link]

In addition to his regular role within U2, The Edge has also recorded with such artists as Johnny Cash, B. B. King, Tina Turner, Ronnie Wood, Jay-Z, and Rihanna. The Edge connected with Brian Eno and Lanois collaborator Michael Brook (the creator of the infinite guitar, which he regularly uses), working with him on the score to the film Captive (1986). From this soundtrack the song "Heroine", the vocal of which was sung by a young Sinéad O'Connor was released as a single.

He also created the theme song for season one and two of The Batman. He and fellow U2 member, Bono, wrote the lyrics to the theme of the 1995 James Bond film GoldenEye. The Edge, along with bandmate Bono, recently composed a musical adaptation of Spider-Man. On May 25, 2011, a single titled Rise Above 1: Reeve Carney Featuring Bono and The Edge was released digitally.^[11] The music video was released on July 28, 2011.^[12]

Musical equipment[link]

Edge's 1964 Vox AC30 on stage in Foxborough for the U2 360° Tour.

The Edge plays electric guitar, acoustic guitar, keyboards, piano, bass guitar (on "40" and "Race Against Time") and lap steel guitar. Compared to many lead guitarists, The Edge is known for using many more guitars during a show. According to his guitar tech Dallas Schoo, a typical lead guitarist uses four or five different guitars in one night, whereas The Edge takes 45 on the road, and uses 17 to 19 in one 2.5-hour concert. He is estimated to have more than 200 guitars in the studio.^{[citation needed]}

Philanthropy[link]

In 2005, The Edge along with Bob Ezrin and Henry Juszkiewicz co-founded Music Rising, a charity that helped provide replacement instruments for those that were lost in Hurricane Katrina. The instruments were originally only replaced for professional musicians but they soon realized the community churches and schools needed instruments as well. The charity's slogan is "Rebuilding the Gulf Region note by note" and has so far helped over a hundred musicians who were affected by Hurricane Katrina. The Edge also serves on the board of the Angiogenesis Foundation, a 501(c)(3) nonprofit organization dedicated to improving global health by advancing angiogenesis-based medicine, diets, and lifestyle.^[13]

See also[link]

• Timeline of U2
• List of people on stamps of Ireland

References[link]

Footnotes

Bibliography

External links[link]

This article's use of external links may not follow Wikipedia's policies or guidelines. Please improve this article by removing excessive or inappropriate external links, and converting useful links where appropriate into footnote references. (October 2011)

Wikimedia Commons has media related to: The Edge

Wikiquote has a collection of quotations related to: The Edge

• U2.com, official U2 site
• Music Rising
• The Edge at the Internet Movie Database
• The Edge – Album Credits
• A Study of The Edge's Guitar Delay
• The Edge: 'It's all about the vision'
• Food Bank For New York City public service announcement
• Comment on the mathematical analysis of The Edge's guitar sound