Glossary

Southern Sonoma County
Resource Conservation District

We hope that this glossary will help you to define a term.
Please select a letter from the table below.

A-B-C-D-E F-G-H-I-J K-L-M-N-O P-Q-R-S T-U-V-W-X-Y-Z

Threatened Species, California. A species of animal or plant is endangered when its survival and reproduction in the wild are in immediate jeopardy form one or more causes, including loss of habitat, change in habitat, over-exploitation, predation, competition, disease, or other factors: or when although not presently threatened with extinction, the species is existing in such small numbers that it may become endangered if its environment worsens. A species of animal or plant shall be presumed to be rare or endangered as it is listed in: Sections 670.2 or 670.5, Title 14, California Code of Regulations; or Title 50, Code of Federal Regulations Sections 17.11 or 17.12 pursuant to the Federal Endangered Species Act as rare, threatened, or endangered.

Threatened Species, Federal. A species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.

Threshold of Significance. The established and identifiable quantitative, qualitative, or performance levels of environmental effect beyond which environmental impacts are considered to be significant. Thresholds of significance are based on current City policy and other normally accepted standards for environmental review.

Urban Growth Boundary (UGB). The line within which all urban development is to be contained.

Viewshed. The geographic area visible from a fixed point.

Volatile Organic Compounds (VOCs). A group of chemicals that react in the atmosphere with nitrogen oxides in the presence of heat and sunlight to form ozone: does not include methane and other compounds determined by EPA to have negligible photochemical reactivity. Examples of VOCs include gasoline fumes and oil-based paints.

Wetlands. An area at least periodically wet or flooded; where the water table stands at or above the land surface (bogs and marshes). Also those areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs, and similar areas.

Wildlife Corridors. A natural corridor, such as an undeveloped ravine, that is frequently used by wildlife to travel from one area to another.

Williamson Act. Known formerly as the California Land Conservation Act of 1965, it was designed as an incentive to retain prime agricultural land and open space in agricultural use, thereby slowing its conversion to urban and suburban development. The program entails a ten-year contract between the City or County and an owner of land, whereby the land is taxed on the basis of its agricultural use rather than its market value. The land becomes subject to certain enforceable restrictions, and certain conditions must be met prior to approval of an agreement.

©2004 Southern Sonoma County Resource Conservation District