Nature
Manure is source of many harmful gases
According the United States Department of Agriculture (USDA), the amount of manure generated in 2005 was estimated to be over 335 million tons of dry matter per year. Much of this manure comes from concentrated animal feeding operations (CAFOs). The largest 2% of all CAFOs produce over 40% of all animals, according to the USDA. READ MORE »
Reactants that form ozone come from natural and human sources
Most emissions, such as volatile organic compounds (VOCs) and nitrogen oxides (NOx), come from both anthropogenic (human-caused) and natural sources. Although it is useful to know how much comes from natural sources, only anthropogenic sources can be controlled.
VOCs and nitrogen oxides are both naturally occuring pollutants that combine in heat and sunlight to form ground-level ozone (O3), which is known to cause respiratory and cardiovascular problems. Ozone pollution can also damage trees and other wildlife. READ MORE »
