User:CanonBrownell/sandbox

Definition
In relation to biological species, it is the maximum population size a given environment can withstand indefinitely while taking into account factors such as food, water, and habitat. It also relies on other factors that are specific to each environment.

Historical cases
The term “carrying capacity” was coined in the late 1890s by range managers concerned with the use of land for grazing livestock. Carrying capacity holds several interpretations in history today. It can relate to natural, environmental, or even socio-economic examples. For this entry, we will focus on how carrying capacity relates to human population. In the last 50 years, the carrying capacity of humans has become a very pressing issue. We have seen an exponential increase in human population over the last 100 years. Researches seem generally uncertain of what human’s carrying capacity is, and what effect it could have on us and the planet.

It is estimated that in 1804 the world reached a population of 1 billion people after thousands, if not millions, of years of reproduction. Skipping ahead to 1987, 183 years later, the world population reached 5 billion. On October 12, 1999, just 12 years later, the population of the world reached 6 billion people. Eleven years after that, on October 31st, 2011, the 7th billion person was born onto planet earth. As we hit each benchmark, concerns of reaching a carrying capacity only increase. Following this trajectory, we could reach a population of 8 billion people by the 2020 US presidential elections.

Scholarly Conversation
Several scholars describe carrying capacity as a highly elusive concept because of practical problems involving measurement. “The hypothetical counting of natural resources, environmental quality standards for air and water, and socio-economic statistics cannot provide an accurate, comprehensive measure of carrying capacity.” (Borthwick, 2011) To bypass these barriers, carrying capacity is often estimated by comparing the demand of natural resources with the availability (supply) of natural resources. Even then, however, numbers can not be fully accurate due to factors such as stress, threshold, and preexisting conditions of an environment. (Borthwick, 2011) Despite this, researches at the University of California Berkley released interesting evidence suggesting that our environment can not deteriorate to a point where humans cannot be supported. (Berck, 2012) This is not to say we do not have a carrying capacity, but that the earth can never reach a point where it will no longer sustain humans. By applying the “Lotka–Volterra predator–prey model”, they created a series of equations to prove that earth’s carrying capacity declines when the environment’s condition declines. This suggests that our population would forcibly decrease before the earth’s sustainable environment is destroyed. They warned that only feelings such as skepticism could weaken people’s concern and care for the environment. And although skepticism of our failing environment is low, reducing the “non-objective noise about the state of the environment is essential to maintain trust and, consequently, a stable course of the environment and population.”

Key Readings
Peter Berck, Amnon Levy, Khorshed Chowdhury, An analysis of the world's environment 	and population dynamics with varying carrying capacity, concerns and 	skepticism, Ecological Economics, Volume 73, 15 January 2012, Pages 103-112, 	ISSN 0921-8009, 10.1016/j.ecolecon.2011.09.019. (http://www.sciencedirect.com/science/article/pii/S0921800911003958)

Alistair G.L. Borthwick, R.Z. Liu, Measurement and assessment of carrying capacity of 	the environment in Ningbo, China, Journal of Environmental Management, 	Volume 92, Issue 8, August 2011, Pages 2047-2053, ISSN 0301-4797, 	10.1016/j.jenvman.2011.03.033. (http://www.sciencedirect.com/science/article/pii/S0301479711000995)