The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water and other necessities available in the environment. In population biology, carrying capacity is defined as the environment's maximal load, which is different from the concept of population equilibrium.

For the human population, more complex variables such as sanitation and medical care are sometimes considered as part of the necessary establishment. As population density increases, birth rate often decreases and death rate typically increases. The difference between the birth rate and the death rate is the "natural increase". The carrying capacity could support a positive natural increase, or could require a negative natural increase. Thus, the carrying capacity is the number of individuals an environment can support without significant negative impacts to the given organism and its environment. Below carrying capacity, populations typically increase, while above, they typically decrease. A factor that keeps population size at equilibrium is known as a regulating factor. Population size decreases above carrying capacity due to a range of factors depending on the species concerned, but can include insufficient space, food supply, or sunlight. The carrying capacity of an environment may vary for different species and may change over time due to a variety of factors, including: food availability, water supply, environmental conditions and living space.

The origins of the term carrying capacity are uncertain with researchers variously stating that it was used "in the context of international shipping" or that it was first used during 19th Century laboratory experiments with micro-organisms. A recent review finds the first use of the term in an 1845 report by the US Secretary of State to the Senate.

Examples[link]

One of the world's best-studied predator-prey relationships is the moose and wolf population of Isle Royale National Park in Lake Superior. Without the wolves, the moose would overgraze the island's vegetation. Without the moose, the wolves would die. The first scientists who studied the issue thought that the wolves would eventually overpopulate and kill all the moose calves, then die from famine. This has not occurred as inbreeding, disease and environmental factors have limited the wolf population naturally.

Easter Island has been cited as an example of a human population crash. When fewer than 100 humans first arrived, the island was covered with trees with a large variety of food types. In 1722, the island was visited by Jacob Roggeveen, who estimated a population of 2000 to 3000 inhabitants with very few trees, "a rich soil, good climate" and "all the county was under cultivation". Half a century later, it was described as "a poor land" and "largely uncultivated". The ecological collapse which followed has been variously attributed to overpopulation, slave traders, European diseases (including a smallpox epidemic which killed so many so quickly, the dead were left unburied and a tuberculosis epidemic wiped out a quarter of the population), social upheaval and invasive species (such as the Polynesian rats which may have wiped out the ground nesting birds and eaten the palm tree seeds). Whatever the combination of factors, only 111 inhabitants were left on the island in 1877. For whatever reasons (whether Moai worship, survival, status or sheer ignorance), the question of how many humans the island could realistically support never seems to have been answered.

The Chincoteague Pony Swim is a human-assisted example.''

Both herds are managed differently. The National Park Service owns and manages the Maryland herd while the Chincoteague Volunteer Fire Company owns and manages the Virginia herd. The Virginia herd, referred to as the "Chincoteague" ponies, is allowed to graze on Chincoteague National Wildlife Refuge, through a special use permit issued by the U.S. Fish and Wildlife Service. The size of both herds is restricted to approximately 150 adult animals each in order to protect the other natural resources of the wildlife refuge.

A further example is the Island of Tarawa, where the finite amount of space is evident, especially since landfills cannot be dug to dispose of solid waste, due to constraints in the subsurface rock and lack of topographic elevations. With colonial influence and an abundance of food (relative to life before the year 1850), the population has expanded to the extent that overpopulation is transparently present.

Mathematics[link]

The Lotka-Volterra equations are simple mathematical model of population dynamics which show how in a closed system, like that of the wolves and moose on Isle Royale, limited prey will cause the predator population to decline rapidly. An extended example can be used where multiple species are competing for the same resources, or single species feed on multiple prey.

Humans[link]

The application of the concept of carrying capacity for the human population has been criticized for not successfully capturing the multi-layered processes between humans and the environment, which have a nature of fluidity and non-equilibrium, and that it often has a blame-the-victim framework.

Supporters of the concept argue that the idea of a finite carrying capacity is just as valid when applied to humans as when applied to any other species. Animal population size, living standards, and resource depletion vary, but the concept of carrying capacity still applies. The carrying capacity of Earth has been studied by computer simulation models like World3.

Food supply and consumption[link]

Carrying capacity, at its most basic level, is about organisms and food supply, where "X" amount of humans need "Y" amount of food to survive. If the humans neither gain or lose weight in the long run, the calculation is fairly accurate. If the quantity of food is invariably equal to the "Y" amount, carrying capacity has been reached. Humans, with the need to enhance their reproductive success (see Richard Dawkins' ''The Selfish Gene''), understand that food supply can vary and also that other factors in the environment can alter humans' need for food. A house, for example, might mean that one does not need to eat as much to stay warm as one otherwise would. Over time, monetary transactions have replaced barter and local production, and consequently modified local human carrying capacity. However, purchases also impact regions thousands of miles away. For example, carbon dioxide from an automobile travels to the upper atmosphere. This led Paul R. Ehrlich to develop the IPAT equation

: ''I = P * A * T'' where: : ''I'' is the impact on the environment resulting from consumption : ''P'' is the population number : ''A'' is the consumption per capita (affluence) : ''T'' is the technology factor

Technology is an important factor in the dynamics of carrying capacity. For example, the Neolithic revolution increased the carrying capacity of the world relative to humans through the invention of agriculture. Currently, the use of fossil fuels has artificially increased the carrying capacity of the world by the use of stored sunlight, albeit at many other expenses. Other technological advances that have increased the carrying capacity of the world relative to humans are: polders, fertilizer, composting, greenhouses, land reclamation, and fish farming.

Agricultural capability on Earth expanded in the last quarter of the 20th century. But now there are many projections of a continuation of the decline in world agricultural capability (and hence carrying capacity) which began in the 1990s. Most conspicuously, China's food production is forecast to decline by 37% by the last half of the 21st century, placing a strain on the entire carrying capacity of the world, as China's population could expand to about 1.5 billion people by the year 2050. This reduction in China's agricultural capability (as in other world regions) is largely due to the world water crisis and especially due to mining groundwater beyond sustainable yield, which has been happening in China since the mid-20th century.

Ecological footprint[link]

One way to estimate human demand compared to ecosystem's carrying capacity is "Ecological Footprint" accounting. Rather than speculating about future possibilities and limitations imposed by carrying capacity constraints, Ecological Footprint accounting provides empirical, non-speculative assessments of the past. It compares historically regeneration rates (biocapacity) against historical human demand (Ecological Footprint) in the same year. One result shows that humanity's demand for 1999 exceeded the planet's biocapacity for 1999 by over 20 percent.

In tourism[link]

''Tourism carrying capacity'' is a now antiquated approach to managing visitors in protected areas and national parks which evolved out of the fields of range, habitat and wildlife management. In these fields, managers attempted to determine the largest population of a particular species that could be supported by a habitat over a long period of time.

See also[link]

Arable land

Asymmetry Principle

Biocapacity

Ecological footprint

Environmental space

Limit load

List of countries by fertility rate

Lotka–Volterra equation

Over-consumption

Overpopulation

Overpopulation in wild animals

Population

Population ecology

Population growth

r/K selection theory

Simon–Ehrlich wager

Thomas Malthus

Tourism carrying capacity

Toxic capacity

Notes[link]

References[link]

Gausset Q., M. Whyte and T. Birch-Thomsen (eds.) (2005) ''Beyond territory and scarcity: Exploring conflicts over natural resource management.'' Uppsala: Nordic Africa Institute

Tiffen, M, Mortimore, M, Gichuki, F. (1994) ''More people, less erosion: Environmental recovery in Kenya''. London: Longman.

Sayre, N.F. (2008) "The Genesis, History, and Limits of Carrying Capacity". ''Annals of the Association of American Geographers'' 98(1), pp. 120–134.

Shelby, Bo and Thomas A. Heberlein (1986) "Carrying capacity in recreation settings." Corvallis, OR: Oregon State University Press.

Karl S. Zimmer (1994) Human geography and the “new ecology”: the prospect and promise of integration. Annals of the Association of American Geographers 84, p. XXX.

External links[link]

http://www.unfpa.org/public/

http://www.isleroyalewolf.org/

http://www.optimumpopulation.org

http://www.DieOff.org

http://www.hartford-hwp.com/archives/24/042.html

http://www.carryingcapacity.org

http://atlas.aaas.org/index.php?part=1&sec;=trends

Category:Ecological metrics Category:Population ecology Category:Population Category:Demography Category:Economic geography Category:Sustainability and population

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Birthname	Richard Douglas Lamm
Image name	Lamm.jpg
Order	38th
Office	Governor of Colorado
Term start	January 14, 1975
Term end	January 13, 1987
Lieutenant	George L. Brown (1975–1979)Nancy E. Dick (1979–1987)
Predecessor	John David Vanderhoof
Successor	Roy Romer
Birth date	September 12, 1935
Birth place	Madison, Wisconsin
Alma mater	University of Wisconsin-Madison
Profession	Co-Director of the Institute for Public Policy Studies at the University of Denver
Party	Democrat
Branch	United States Army
Serviceyears	1957-1959
Battles	Vietnam War
Rank	First Lieutenant
Footnotes	}}

Richard Douglas "Dick" Lamm (born September 12, 1935) is an American politician, Certified Public Accountant, college professor, and lawyer. He served three terms as 38th Governor of Colorado as a Democrat (1975–1987) and ran for the Reform Party's nomination for President of the United States in 1996.

He is currently the Co-Director of the Institute for Public Policy Studies at the University of Denver

Early life and education[link]

Richard Douglas Lamm was born in Madison, Wisconsin. He graduated from high school in Pittsburgh, Pennsylvania, and attended the University of Wisconsin–Madison, where he majored in accounting. Lamm spent his college summers working as a lumberjack in Oregon, a stockboy in New York, and helping out on an ore boat. Lamm graduated from college in 1957, then served one year of active duty as a first lieutenant in the United States Army at Fort Carson in Colorado and Fort Eustis in Virginia until switching to reserve duty in 1958.

From 1958-1960 Lamm lived in Salt Lake City, San Francisco, and Berkeley, holding jobs as an accountant, tax clerk and a law clerk.

Lamm attended law school at the University of California, graduated in 1961, then moved to Denver in 1962, where he worked as an accountant and then set up a law practice. Lamm took to the Colorado lifestyle, becoming an avid skier, mountain climber, hiker, and member of the Colorado Mountain Club. He joined the faculty of the University of Denver in 1969 and has been associated with the University ever since.

Since 1963 he has been married to "Dottie" Lamm, a former airline flight attendant and newspaper columnist. In 1998 she won the Democratic nomination for the US Senate from Colorado, but lost in the general election to incumbent Republican Ben Nighthorse Campbell.

Lamm was selected as one of Time Magazine's "200 Young Leaders of America" in 1974, and won the Christian Science Monitor "Peace 2020" essay in 1985. In 1992, he was honored by the Denver Post and Historic Denver, Inc. as one of the "Colorado 100" - people who made significant contributions to Colorado and made lasting impressions on the state's history. He was Chairman of the Pew Health Professions Commission and a public member of the Accreditation Council for Graduate Medical Education.

Political activities[link]

Colorado House of Representatives[link]

In 1964 he was elected to the Colorado House of Representatives as a Democrat from an affluent district near the University of Denver. In 1967, he drafted and succeeded in passing the nation's first liberalized abortion law. He was an early leader of the environmental movement, and was President of the First National Conference on Population and the Environment.

In 1972, as a member of the Colorado General Assembly, Lamm led the movement against Denver's hosting of the 1976 Winter Olympics. Denver had already been awarded the games, but the movement succeeded in cutting off public funding for the games, forcing the city to cancel its hosting. Innsbruck, Austria replaced Denver as the host. Lamm's successful effort made him known statewide.

Colorado governor[link]

Lamm ran for Governor of Colorado in 1974 on a platform to limit growth, and was elected. Reacting to the high cost of campaigning, he had walked the state in his campaign.

One of his acts as governor was designating musician John Denver as the Poet Laureate of Colorado.

As candidate and then governor, Lamm promised for environmental reasons to "drive a silver stake" through plans to build Interstate 470, a proposed circumferential highway around the southwest part of the Denver Metropolitan Area. However, continued development in the area led to increased congestion on surface streets, and the highway was later built, largely with state funds, as Colorado State Highway 470.

In 1984, his outspoken statements in support of physician-assisted suicide generated some controversy, specifically over his use of the phrase "we have a duty to die." Lamm later explained that he "was essentially raising a general statement about the human condition, not beating up on the elderly," and that the exact phrasing in the speech was "We've got a duty to die and get out of the way with all of our machines and artificial hearts and everything else like that and let the other society, our kids, build a reasonable life." His dire predictions for the future of social security and health care ("duty to die") earned him the nickname "Governor Gloom".

Lamm was elected Colorado governor three times. When he left office in 1987 after three terms and twelve years in the office, he was the longest-serving governor in state history (his successor, Roy Romer, matched this record).

Later political campaigns[link]

In 1990, state party leaders tried to get Lamm to run for the U.S. Senate seat being vacated by Sen. Tim Wirth, also a Democrat, but Lamm declined. In 1992 he ran for the U.S. Senate but suffered his first political defeat. Ben Nighthorse Campbell beat him in the Democratic primary and went on to win the seat. (Nighthorse Campbell later switched to the Republican Party.)

In 1996 Lamm, while noting that he was still a registered Democrat, criticized both his own Democratic Party and the Republican Party, saying "I think both political parties are controlled by special interest money, and I've had enough of it." and "The Democrats are too close to the trial lawyers and the National Education Association. The Republicans are too close to the radical right." On July 9, 1996, he formally announced his intention to run for the nomination of the Reform Party for the U.S. Presidency. Less than 48 hours after Lamm announced his candidacy, Ross Perot, who built the Reform Party from his United We Stand America organization, said he would run as the Reform Party nominee if drafted. In early August, Lamm picked former California Republican congressman Ed Zschau, a high-tech millionaire and proven fund-raiser, to be his running mate on the presidential ticket. Ultimately, however, Perot won 65.2 percent of the 49,266 votes cast by party members nationwide, Lamm winning just 34.8 percent.

Writer and novelist[link]

In 1985, while still in the governor's office, he tried his hand as a novelist. The resulting novel, ''1988'', was a story about a former Democratic governor of Texas running for U.S. President on a populist, third-party ticket, declaring himself a "progressive conservative." The main character bore a number of similarities to Lamm himself, in his stated political positions, his background as a Democratic governor, as well as presaging Lamm's own unsuccessful run for the Reform Party nomination in 1996. However, the main character in ''1988'' was also portrayed as a pawn of an international conspiracy to capture the White House.

A voluminous writer, Lamm's other works include ''Population and the Law'' (1972), ''Some Reflections on the Balkanization of America'' (1978), ''Megatraumas: America at the Year 2000'' (1980), ''Energy Activities in the West'' (1980), ''The Angry West: A Vulnerable Land and Its Future'' (1982), ''Campaign for Quality: An Education Agenda for the 80's'' (1983), ''Pioneers and Politicians: Ten Colorado Governors in Profile'' (1984), ''Copernican Politics'' (1984), ''The American West: A poem'' (1985), ''Immigration Time Bomb: The Fragmenting of America'' (1985), ''The Lamm Administration: A Retrospective'' (1986), ''California Conspiracy'' (1988), ''Hard Choices'' (1989), ''Crisis: The Uncompetitive Society'' (1989), ''The fall and Rise of the American Economy'' (1989), ''Indicators of Decline: An article from The Futurist'' (1993), ''The Supply Factor in Health Care Cost Containment'' (1993), ''The Ethics of Excess: An article from The Hastings Center Report'' (1994), ''Health Care Workforce Reform.: An article from State Legislatures'' (1994), ''The West at Risk'' (1994), ''Futurizing America's Institutions.: An article from The Futurist'' (1996), ''The price of Modern Medicine'' (1997), ''Mountains of Colorado'' (1999), ''Government does, indeed, ration health care: An article from State Legislatures'' (1999), ''Redrawing the Ethics Map.: An article from The Hastings Center Report'' (1999), ''Vision for a Compassionate and Affordable Health System'' (2001), ''Brave New World of Health Care'' (2003), ''The Brave New World of Health Care'' (2004), ''The Challenge of an Aging Society: The Future of U.S. Health Care'' (2005), ''Two Wands, One Nation: An Essay on Race and Community in America'' (2006) and ''Condition Critical: A New Moral Vision of Health Care'' (2007).

Activities since leaving political office[link]

After leaving office, Lamm has continued to speak publicly on environmental, immigration reduction, and health care issues.

In 2004 Lamm unsuccessfully ran for a seat on the Board of Directors of the Sierra Club. He urged that the Sierra Club advocate immigration controls as a way to limit environmental degradation due to population growth. During a 2011 interview, Lamm clarified that he believes "legal immigration has been good for America. The success of Silicon Valley shows we need entrepreneurial immigrants with skills to bring to our country!”

Lamm serves as the Chairman of the Advisory Board of the Federation for American Immigration Reform (FAIR), and on the Board of Directors of the Diversity Alliance for a Sustainable America (DASA). He is the Co-Director of the Institute for Public Policy Studies at the University of Denver. He authored a book, ''The Brave New World of Health Care'', a criticism of current United States health care policies and proposals for reforming them. (Fulcrum Publishing, ISBN 1-55591-510-8) Lamm also served on the board of directors of American Water Development Inc, along with, among others, Maurice Strong, Samuel Belzberg, Alexander Crutchfield and William Ruckelshaus.

In 2005, a 2004 speech by Lamm titled "I Have a Plan to Destroy America," became famous after being frequently forwarded as an email; in it he criticizes multiculturalism.

In 2006, he wrote ''Two Wands, One Nation'', a controversial essay in which he advocates that black and Hispanic Americans embrace "Japanese or Jewish values". The essay was strongly criticised by some blacks and Hispanics.

Dick Lamm currently sits on the board of directors for the Energy Literacy Advocates.

References[link]

Quotes[link]

"My sixth point for America’s downfall would be to include dual citizenship and promote divided loyalties. I would celebrate diversity over unity. I would stress differences rather than similarities. Diverse people worldwide are mostly engaged in hating each other—that is when they are not killing each other." – How to Destroy America

"The U.S. economy will be debt-ridden, with structural unemployment nearing 20 percent. The U.S. will have the lowest percentage of capital investment and lowest growth in productivity and savings of any major industrialized country. The middle class will be wiped out by these inter-related economic predicaments. … The U.S. has the most expensive and inefficient health-care system in the world." – Megatraumas: America at the Year 2000

External links[link]

DU Portfolio Community, ''Dick Lamm''

Richard Lamm on Multiculturalism, Snopes article

Lamm's words draw fire Rocky Mountain News article

Ubben Lecture at DePauw University

Category:1935 births Category:Living people Category:American anti–illegal immigration activists Category:American conservationists Category:American non-fiction environmental writers Category:Chi Psi Fraternity Category:Colorado Democrats Category:Governors of Colorado Category:Members of the Colorado House of Representatives Category:People from Madison, Wisconsin Category:Reform Party of the United States of America politicians Category:Sustainability advocates Category:United States presidential candidates, 1996 Category:University of California alumni Category:University of Denver faculty Category:University of Wisconsin–Madison alumni Category:Writers from Colorado Category:Writers from Wisconsin

de:Richard Lamm sv:Richard Lamm