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Algal bloom: Rapid growth by algae producing large quantities of plant material which can result in low dissolved oxygen conditions as the algae dies and decays. Low dissolved
oxygen can result in the death of fish and other aquatic organisms.
Antibiotic resistance: Frequent exposure to an antibiotic provides conditions favorable to
the evolution of germs which are resistant to (i.e. not harmed by) that antibiotic.
Average trophic transfer efficiency: Amount of food eaten which is converted to animal
tissue. Typically, an animal requires 10 pounds of food to produce 1 pound of animal tissue, hence a trophic efficiency of 10%.
Estuaries: Where the ocean and rivers meet and mix. Estuaries are very important for fish and shellfish production, especially in providing nursery habitat.
Floodplains: Frequently inundated (flooded) lands bordering rivers and streams.
Groundwater: Water beneath the ground held in porous rock. Groundwater is an important
source of water for humans, and also supplies rivers, lakes, streams, estuaries, and other waterways.
Heavy metals: A classification of elements, many of which are necessary for animal nutrition
in trace quantities but which are also toxic to plants and animals in low concentrations.
Lagoon: As used in this context, a vessel, usually open air and in the ground, that provides
storage and limited treatment of hog waste and associated water that has been flushed out of the hog houses.
Nitrates: A nitrogen-containing compound that is water soluble and mobile in the
environment. Nitrates are toxic at elevated concentrations (public health standard set at 10 parts per million). Groundwater nitrate contamination can present a threat to public health.
Nutrient pollution: Pollution containing nitrogen and/or phosphorus which stimulates aquatic
algal growth, thus robbing waters of oxygen and killing fish and other aquatic organisms. Nutrient pollution comes from runoff of excess fertilizers, animal waste, and other diffuse
sources, as well as from waste water treatment plants and some industries.
Pathogens: Disease-causing organisms.
Pfiesteria: A toxic microorganism capable of killing fish and subsequently feeding off their flesh. Usually found in brackish waters. Pfiesteria has been associated with waters polluted
with excessive nitrogen and phosphorus, but current scientific evidence is inconclusive and ongoing.
Setbacks: Distance away from a feature which is supposed to provide a buffer to reduce transport of pollutants to areas of concern such as residences or waterways.
Sprayfield: Land (near the hog lagoon) on which the hog waste is applied. High-powered
spray guns spray the hog waste high in the air and it drifts back onto the land.
Surface water: Water flowing on surfaces such as rivers, streams, lakes, estuaries, and oceans.
Vertical integration: In this context, an economic term describing the U.S. pork industry. It
means that a small number of companies are involved in more than one, and usually several, phases of pork production. Large factory farming companies ("integrators") combine
company-owned farms, contract farms, and farming-related businesses (feed mills, transportation, etc.) under a single company banner.
Volatile organic compounds: Natural or manmade gaseous hydrocarbons which can be active components in atmospheric chemistry.
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