AGRICULTURE AS A CONTRIBUTOR TO CLIMATE CHANGE

According to the Intergovernmental Panel on Climate Change, the three main causes of the increase in greenhouse gases observed over the past 250 years have been fossil fuels, land use, and agriculture. Agriculture has been shown to produce significant effects on climate change, primarily through the production and release of greenhouse gases such as carbon dioxide, methane, and nitrous oxide.

Deforestation as a contributor to climate change

It is important, first to understand what a precious resource rainforests play in our world. They form part of a delicate ecosystem that has taken millions of years to evolve. Rainforests every year help to absorb almost 20% of man-made CO2 emissions therefore deforestation can be classed as a major contributor to the causes of climate change. Cutting down rainforests faster than they can be replaced has a devastating effect on the carbon emission cycle producing an extra 17% of greenhouse gases. Remember trees absorb CO2. More deforestation means more CO2 build up in the atmosphere.

Climate change can make pesticide contamination challenges worse. Under warmer conditions, some pesticides will spread further, more readily to contaminate water supplies, and have more acutely toxic effects. If those effects are not controlled, farm towns and wild spaces will face a one-two punch as global warming and pesticide contamination interact to make each problem worse.

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Deforestation as a contributor and a Plane spraying pesticides

DDT

DDT is a colorless chemical pesticide, dichlorodiphenyltrichloroethane, used to eradicate disease-carrying and crop-eating insects. It was first isolated in Germany in 1874, but not until 1939 did the Swiss Nobel Prize-winning chemist Paul Müller recognize it as a potent nerve poison on insects. First used heavily in World War II for preinvasion spraying, DDT was disseminated in great quantities thereafter throughout the world to combat yellow fever, typhus, elephantiasis, and other insect-vectored diseases. In India, DDT reduced malaria from 75 million cases to fewer than 5 million cases in a decade. Crops and livestock sprayed with DDT sometimes as much as doubled their yields. It is one of the oldest and most dangerous pesticides hailed as a chemical miracle (Getis et al, 2006)

With the publication of the American marine biologist Rachel Carson’s Silent Spring in 1962, suspicion grew that DDT, by entering the food chain and eventually concentrating in higher animals, caused reproductive dysfunctions, such as thin eggshells in some birds. Some insect pests also gradually developed DDT-resistant strains whose populations grew unchecked while their natural predators, such as wasps, were being eradicated by spraying. In 1973 DDT was banned in the U.S. except for use in extreme health emergencies. Many other nations have also banned it or placed it under strict control.(Encarta, 2009)

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