Different agricultural producers account for approximately 8% of greenhouse gases, which come primarily from livestock, agricultural soils, and the production of rice. The management of agricultural soils is responsible for about 50% of the nitrous oxide emissions. Natural soil structure is disturbed by tillage, animals, weather, and mobile sources. The soil is broken into smaller pieces which can then cause soil erosion and the smaller pieces also may become airborne. Livestock always produce methane as part of their digestive process. This is about 33% of the methane produced by agriculture. Manure storage produces methane and nitrous oxide and accounts for 15% of the total greenhouse gas emissions from agriculture in the United States. Rice cultivation produces methane, and burning crop residue produces methane and nitrous oxide. Two weather- related events have the potential to increase the concentration of PM10. They are high winds and stagnation of an air mass.
Best Practices for Agriculture (See endnote 25)
Note: Not all Best Practices will work equally well in all agricultural settings and for all agricultural categories such as tillage and harvest, non-cropland, and cropland. There are variations in wind, soils, moisture conditions, and management approaches.
- • Discontinue all night tilling between 2 AM and 8 AM when stagnant air conditions are most prevalent.
- • Apply the fertilizer, pesticides, or other agricultural chemicals through an irrigation system.
- • Modify the equipment to prevent or reduce the amount of particulate matter.
- • Harvest a forage crop (alfalfa, winter forage, silage corn) without allowing it to dry, which decreases the use of equipment that stirs up dust.
- • Monitor crops for pests and incorporate biological processes to reduce spraying of chemicals.
- • When the wind speed is 25 mph or more limit all tillage and harvesting.
- • Use multiyear crops where possible.
- • Plant specific crops that will accommodate to the amount of soil moisture present in the land being used.
- • Reduce tillage to a minimum, and time the work properly.
- • Use genetically modified crops that can reduce tillage and soil disturbance.
- • Restrict or eliminate public access to non-croplands.
- • Erect artificial wind barriers.
- • Use the proper trees, shrubs, vines, grasses, or other vegetative cover on non-cropland areas.
- • Reduce the vehicle speed of all farm vehicles to 20 mph or under.
- • Use synthetic particulate suppressants such as calcium chloride, processing byproducts of soybean feedstock, lignin, polyvinyl acrylic polymer emulsion, etc.
- • Plan strips of alternating crops or vegetative strips within the same field.
- • Use crop or other plant residues on the soil surface to control erosion.