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Composting is an effective way to reduce greenhouse gases. A compost process is either aerobic or anaerobic. Anaerobic composting is when. organic materials-or coinpostables-break down by bacteria without the presence of oxygen. This process, which happens in landfills, produces methane, carbon dioxide, and trace amounts of other gases. Aerobic composting is when organic material breaks down by bacteria in the presence of oxygen.. The end byproducts in aerobic composting are mainly carbon dioxide anal water, and nutrient-packed soil of .finished compost. lay composting these materials, the generation. of greenhouse gases, particularly methane, is avoided. Backyard composting and well-nin industrial compost operations will produce negligible greenhouse gas emissions (mostly from the operation of tractors and other equipc.nent). Composting also has "upstream" benefits, which further conserve our resources and reduce greenhouse gas emissions. When this cornpost is used on fields it displaces synthetic chemical fertilizers. Fertilizer production requires intensive fossil fuel energy and seriously impacts human and environmental health (Pimental, et a1., 2005). fay using compost: o The greenhouse gas emissions related to fertilizer production are ~ ~~: avoided o There is significant reduction in the use of pesticides (avoiding emissions associated with their production} o Improves health and workability of soils, resulting in less fuel consumption to till the soil a Helps soils hold or sequester carbon dioxide ~. 5 .~ . ` '~ ,: In addition to these emission reductions, compost replenishes and revitalizes exhausted farm soils by replacing trace minerals and organic material, reduces soil erosion anal helps prevent storm water nmofi: In fact, a single 40-pound bag contains the equivalent of 2.5 gallons of gasoline. In addition to their oil base, synthetic fertilizers are spiked with concentrated forms of nitrogen and phosphorus, which are harder for plants to absorb than their naturally occurring counterparts. The excess phosphorus and nitrogen, not absorbed by plants, runs off into storm drains that feed into rivers and streams, contributing to algae blooms that deprive waterways of oxygen and kill off aquatic life (National Geographic Society, 2x08). What about the environmental costs to collect and process recycling and composting? Recycling and composting do require transportation and ~~~ ~ processing. The environmental costs from trucks and `- ~ .~ ~ equipment to process the materials are real; however they are ,,,~ small compared to the energy savings anal environmental _ ~ benefits from recycling and composting materials. For instance, Page 5