There are also certain negative effects connected with agricultural practices associated with global warming. Attention is being focused on the gases emitted from cow herds in agricultural areas. According to a report on LiveScience in July 2005, eight pregnant Holstein cows are being used in a controlled environment to detect resultant gas levels and determine their negative effects. In fact, researcher Frank Mitloeh-ner of the University of California has eight cows confined inside what he refers to as a "bio-bubble" (a big white tent) to answer an extremely important question: How much gas does a cow actually emit?
This study is unique because it will not only answer the basic question as to how much gas is contributed to the atmosphere by cattle; it has a secondary aspect, as well. Findings will also be used to help write California's first air-quality regulations to involve the agricultural industry—the first attempt of its kind in the nation. As a result, dairies may eventually have to apply for air-quality permits and begin using equipment designed to minimize and eliminate air pollution, just as other industries must currently do.
Based on outdated information (collected in the 1930s), cows produce 12.8 pounds of volatile organic compounds (VOCs) a year. Current estimates of VOCs, however, have been suggested to be as high as 20.6 pounds per cow per year. In order to gain the most precise readings possible, the air is monitored in the confined area by equipment so sensitive that it is able to detect one molecule out of a trillion.
According to Mitloehner, one of the most surprising results of the experiment was that the most significant greenhouse gas emissions were not a result of the manure. According to him, "We thought it was the waste that would lead to the majority of the [greenhouse gas] emissions, but it seemed to have been the animals."
The major contributor to greenhouse gases was the ruminating process. During a cow's digestion process, as food enters the stomach, it mixes with bacteria, which breaks the food down and produces methane (a greenhouse gas). Roughly 20 minutes later, the food returns to the cow's mouth as cud, which it chews, thereby releasing methane into the air. In addition to methane, it also releases methanol and ethanol, as well as VOCs.
As the population becomes more environmentally aware, it has spurred the notion that the agricultural sector may need to be regulated for pollution control as much as any other industrial sector that releases greenhouse gases into the atmosphere. Other researchers, such as J. P. Cativiela of Dairy CARES, an industry-fUnded environmental group, have countered the notion, however, suggesting that changing a cow's food type may be more effective than investing in and implementing expensive technologies. Others, principally environmentalists, argue that the whole issue is overexaggerated and not as serious as it has been portrayed. For example, Brent Newell of the Center on Race, Poverty, and the Environment says: "It doesn't take into account the lagoons that store the waste or the decomposing feed, the decomposing corn stored in a dairy."
Another negative impact concerns manure management. The decomposition of animal waste in an anaerobic (oxygen-free) environment produces methane. According to the Environmental Protection Agency (EPA), manure storage and treatment systems are responsible for about 9 percent of the total methane emissions in the United States, and 31 percent of the methane emissions coming from the agricultural sector alone.
Methane has an enormous greenhouse gas potential. It is about 21 times more effective at trapping heat than CO2. In fact, 10 percent of the warming in the United States caused by global warming is due to methane alone. More than 80 percent of the methane emissions that originate from animal wastes come from liquid-based manure management systems that include the following:
• anaerobic lagoons,
Another management option—that of spreading manure on agricultural fields as fertilizer—does not produce significant amounts of greenhouse gas. Its drawback, however, is that it can be washed off the surface of the ground and infiltrate streams and groundwater, polluting those valuable resources.
According to the EPA, emissions from liquid manure management practices that cause greenhouse gas emissions have been steadily increasing since 1990, due to increasing animal populations. This trend
is expected to continue. Two major health issues have been identified as a result: odor control and water-quality issues. Also added to the concern is that urban areas are beginning to expand and encroach on rural areas, which means negative impacts for residential areas.
According to the EPA, one solution that has been suggested to combat this problem is the use of anaerobic digester systems. An anaerobic digester is a container similar to a covered lagoon that is designed to hold decomposing manure under warm, oxygen-free conditions that promote the growth of naturally occurring bacteria. The purpose of the bacteria is to digest the manure, producing methane and an effluent that farmers can use in place of untreated manure.
This technology is not new; it has actually existed since the 1920s. During World War II in Europe, when petroleum was scarce, anaerobic digesters used heat and bacteria to eat animal waste, which allowed the Europeans to capture and burn the methane gas for energy. Only during the past decade, this technology has become recognized in the United States as a viable option for the production of energy and mitigation of global warming.
The by-product (methane) produced by these digesters is called "biogas," and it can now be used effectively as an energy source. The gas is collected in perforated pipes and transmitted to an electric generator or boiler. Once the biogas is produced, farmers can use it as an energy source to produce electricity, heat their water, or use it to generate refrigeration. Depending on how much they generate, they may also have the option to sell "extra" electricity directly to local utility companies. Secondary benefits include a reduction of odors, methane emissions, and surface/groundwater contamination. Farmers can also sell the resulting high-quality fertilizer. These related business opportunities help the overall position of U.S. agribusiness.
One example of an area whose agricultural business sector has benefited is Craven Farms of Cloverdale, Oregon. According to a report issued by the EPA, Craven Farms annually produces $24,000 of electricity and $30,000 of digested solids with its biogas system. The EPA contends that "maximizing farm resources in this way may help farmers remain competitive and environmentally sustainable in today's livestock industry."
Also, based on EPA findings, digested wastes are biologically stable when compared with untreated manure, and when they mineralize, they have a higher ammonium content that allows crops to utilize it. They also reduce the likelihood of surface or groundwater pollution. In addition, they reduce pathogen populations in manure, destroy weed seeds (such as from invasive species), and control unpleasant odors.
The federal AgSTAR Program maintains there are about 3,000 livestock facilities across the United States that could install cost-effective biogas recovery systems, with the potential to recover 470,000 tons (426,000 metric tons) of methane. The AgSTAR Program is a voluntary effort jointly sponsored by the U.S. Environmental Protection Agency (EPA), the U.S. Department of Agriculture (USDA), and the U.S. Department of Energy (DOE). The program encourages the use of methane recovery (biogas) technologies at the confined animal feeding operations that manage manure as liquids or slurries. These technolo gies reduce methane emissions while achieving other environmental benefits.
Fertilizer management is another area of concern. Based on information collected by the EPA, the use of synthetic nitrogen and organic fertilizers has contributed to about 36 percent of total U.S. nitrous oxide (N2O) emissions. Nitrous oxide is about 310 times more effective at trapping heat in the atmosphere than CO2. While most N2O is produced naturally through microbial processes in the soil, it is the addition of synthetic N2O introduced through fertilizers that has led to an increase in emissions from agricultural lands. According to the IPCC, if fertilizer applications are doubled, emissions of N2O will double. Therefore, the IPCC has recommended that nitrogen fertilizer be used more efficiently in order to reduce N2O emissions. Simultaneously, reducing the amount of fertilizer used will also decrease the CO2 emissions that occur during the fertilizer manufacturing process (which relies on energy generated from fossil fuels).
The federal government is also playing a role in an effort to encourage a reduction in the generation of greenhouse gases. Under the Climate Change Action Plan, the U.S. Department of Agriculture is sponsoring projects and demonstrations to help farmers improve their efficiency in the use of nitrogen fertilizers.
The federal Environmental Quality Incentives Program (EQIP), established under the 1996 Farm Bill, offers cost-sharing and incentive payments for land management practices such as nutrient and manure management.
In another program through the USDA's Natural Resource Conservation Service, private insurers in some states now offer crop insurance that protects farmers against potential yield reductions associated with the use of alternative nitrogen management techniques. This insurance provides a "safety net" to farmers so that they will be willing to experiment with other techniques.
According to the Food and Agriculture Organization (FAO) of the United Nations, agriculture and deforestation account for about one-third of global greenhouse gas emissions from human activities. Of these, approximately 80 percent of the total emissions come from developing countries. In addition to the production of crops, livestock in developing countries is also in serious trouble as tens of thousands of animals die from heat waves and lack of water and proper nutrition. In fact, many breeds of livestock cannot be genetically improved fast enough to adapt to climate change.
Based on data from the FAO, a rise in temperature of 5°F (3°C) could jeopardize water supplies for 155 to 600 million people in the Near East alone. Hunger is already a serious problem in many parts of the world, such as Africa. According to the FAO, agriculture could be made nearly carbon neutral using available technologies and proper land management practices.
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Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.