Agriculture and Climate Change
Environmental Impacts of Agriculture.
In the previous section we discussed a few of the ways in which agriculture plays a role in deforestation, and in particular, we described some of the most significant drivers of tropical deforestation, namely the timber industry, the production of palm oil, soy beans, as well as cattle ranching.
In terms of environmental impact, deforestation is often linked to certain side effects. These include soil erosion, a loss of habitat, and a loss of biodiversity. This loss of biodiversity includes a wide variety of plants, animals and insects, and even a loss of microbes that live naturally in the fertile soil, where they are unintentionally impacted by the presence of fertilizers and pesticides.
Agriculture also leads to aquatic pollution. For example, when animal waste, pesticides, and fertilizers find their way into streams and rivers, they not only impact these particular aquatic eco-systems, they can also end up in the ocean where they create aquatic ‘dead zones’ along the coast. The potential impact of agricultural pollution is broad and often far-reaching.
But in terms of environmental impact, and perhaps most importantly in relation to our discussion here, the loss of trees has a significant impact on global warming and climate change.
Greenhouse Gases and Carbon Sequestration.
You might be asking,- how does deforestation, and the loss of trees, contribute to global warming? The answer is that living trees absorb carbon dioxide, mitigating and partially offsetting the greenhouse gas emissions produced by our burning of fossil fuels.
Scientists refer to this process as “carbon sequestration,” and it is defined as the capture and storage of excess carbon dioxide. Trees play an important role in carbon sequestration, and we refer to our forests as “carbon sinks” because of their important function of removing and storing harmful carbon dioxide. In fact, of all the trees around the world, tropical trees alone are estimated to provide a large share of the climate mitigation that’s needed to offset climate change.
Burning Trees and the Release of Carbon.
The process of removing trees to create farmland, whether the purpose is for growing crops, or for grazing cattle, not only removes the vegetation we need to offset climate change, it can actually contribute damaging greenhouse gases to the environment.
This can happen because instead of being cut down and removed, forest land is sometimes cleared by a process of controlled burning. During the process of burning, the flames and smoke from the burning trees release all of the carbon that has been stored inside the trees for all of the years that they’ve been growing.
As a result of the combination of reasons mentioned above, the Food and Agriculture Organization of the United Nations tells us that deforestation is the world’s second-overall leading cause of climate change.
In addition, the Union of Concerned Scientists U.S.A. informs us that deforestation is responsible for approximately 10 percent of all global warming emissions.
Animal Agriculture and Greenhouse Gases.
In addition to deforestation, the Food and Agriculture Organization of the United Nations also informs us that the animal agriculture sector, (which includes the production of feed crops for animals, the manufacturing of fertilizer, as well as the shipment of meat, eggs, and milk), is itself a primary contributor of green house gas emissions.
These green house gas emissions come from a broad spectrum of sources stemming from animal agriculture, including methane emissions directly from the livestock, carbon emissions resulting from their transport, as well as the emissions from the decay of their organic waste. (This ‘organic waste’ includes a vast amount of manure used as fertilizer.)
By contributing green house gases in all of these different ways, animal agriculture is literally choking the life out of our planet. The longer we ignore it, the deeper in we get, and the more we limit our ability to protect our health and save our environment. Raising livestock for meat, eggs and milk generates a significant percentage of global greenhouse gas emissions, and is a major contributing factor to global warming.
Next up: Global Habitat Destruction and Ways That You Can Make a Difference!