According to the United Nations, by 2050, the world population could reach 8.9 billion, or even be as high as 10.6 billion. A growing population demands more food, but it is getting ever more difficult to meet the demand.
Instead of using pesticides, crops can be rotated to prevent populations of pests from becoming established. Different varieties of crops can be grown beside each other to reduce the concentration of pests and preserve biodiversity. Growing healthier plants can also reduce the impact of pests. Instead of using fertilizer, soil can be enriched naturally, by adding composted material, for example.
Another way to eliminate pests is by managing farms in order for them to harbour populations of natural predators. Birds, bats, spiders, and ladybugs are all organisms that hunt pests, and providing an environment beneficial to them is not only good for pest control, but also for the biodiversity of the surrounding ecosystem.
Sustainable agriculture methods are actually effective enough to meet the demand for food, with a minimal environmental impact. If we continue to pollute through industrial agriculture, both the environment and the human population will suffer. Sustainable agriculture is a means to prevent further damage, and it works.
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"Sustainable Agriculture Techniques." Food & Agriculture. The Union of Concerned Scientists, 24 Aug. 2008. Web. 12 Jan. 2011. http://www.ucsusa.org/food_and_agriculture/science_and_impacts/science/sustainable-agriculture.html
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