anaerobic: without oxygen.

aquitard: an underground bed or layer of soil, rock, or clay that is too dense to allow easy passage of water.

best management practices (BMPs): structural or nonstructural methods that prevent or reduce the movement of sediment, nutrients, pesticides, and other pollutants from the land to surface or ground water.

bioavailability: the degree to which pollutants in contaminated soil are available for biodegradation.

bole: the trunk of a tree.

buffer: a linear patch. The buffer�s linear shape may help the buffer perform certain functions, such as screening undesirable views and increasing habitat connectivity.

buffer area ratio: the ratio of upslope runoff-contributing area to buffer area that the runoff flows into.

carbon sequestration: the removal of carbon dioxide from the atmosphere.

c-factor: the ratio of soil loss from land under a specific crop and management system to soil loss from continuously fallow and tilled land.

concentrated flow: runoff that accumulates or converges into well-defined channels.

connectivity: the ease with which organisms and materials can travel between two points.

conservation tillage: a system of crop production in which the soil is disturbed as little as possible.

corridor: a linear patch. The corridor�s linear shape may help the corridor perform certain functions, such as screening undesirable views and increasing habitat connectivity.

denitrification: bacterial reduction of nitrite to gaseous nitrogen under anaerobic conditions.

deposition: the geological process by which material is added to a landform or land mass.

dispersal: the process or result of organisms or particles spreading from one place to another.

ecosystem services: consumable and non-consumable services that an ecosystem provides to humans.

edge effects: the ecological effects that result when two or more habitat types meet at an interface. Edge can occur naturally or artificially, and artificial creation of edge can have negative impacts if it alters ecological processes.

filter strip: strip or area of vegetation used for removing sediment, organic matter, and other pollutants from runoff and wastewater.

Geographic Information System (GIS): a system of hardware and software used for storage, retrieval, mapping, and analysis of geographic data.

groundwater recharge: inflow of water to a groundwater reservoir from the surface.

hydric soil: a soil formed under conditions of saturation or flooding, where these conditions last long enough during the growing season so that anaerobic conditions develop in the upper part of the soil.

karst: an area of irregular limestone in which erosion has produced fissures, sinkholes, underground streams, and caverns.

koc value: a measure of how tightly a pesticide binds or sticks to soil particles. The larger the Koc, the more strongly the pesticide is held to soil organic matter and the less likely it will leach.

impervious cover: any hard surface material such as roof tops, asphalt, or concrete that limits infiltration and induces high runoff rates.

infiltration: the downward entry of water into the soil or other material.

leachate: a liquid that has come in contact with or been released from waste.

mass slope failure: the downslope movement of material on an unstable slope.

matrix: the background within which patches and buffers exist.

migration: the periodic passage of groups of animals from one region to another for feeding or breeding.

parasitism: a relationship between two species of organisms in which one benefits at the expense of the other, without killing it.

patch: a relatively small area that has distinctly different structure and function than the surrounding landscape.

pathogens: microorganisms that can cause disease in other organisms or in humans.

permeability: the ability of a material to allow the passage of a liquid.

phytoremediation: the use of plants to clean up soil and water contaminated with metals, solvents, and other pollutants.

porosity: a measure of the void spaces in a material.

predation: the act of capturing another organism for use as food.

refugia: locations in which species have persisted while becoming extinct elsewhere.

riparian areas: transitional areas between those characterized by terrestrial and aquatic ecosystems. Riparian areas are distinguished by gradients in bio-physical conditions, ecological processes, and biota.

sensitive non-target areas: areas adjacent to chemical spray application areas and considered off-limits to spray drift.

soil cohesion: the ability of a soil to hold itself together.

stepping stones: small patches of habitat that allow for species movement between large patches.

targeting: focusing preservation, conservation, or other management practices on specific portions of the landscape where they will have the greatest benefits.

windthrow: uprooting of trees by wind.