7. PRSR 04-11-2007 - Laserfiche WebLink

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'Glossary of Technical Terms Acre-Foot Volume of water that would cover an acre of land to a depth of one foot (43,560 cubic feet). Alluvium Material, such as sand and gravel, deposited by running water. River terraces and outwash plains are examples of landforms composed of alluvium. Barrens Usually refers to an area with sparse vegetation or stunted plants, caused by harsh growing conditions such as infertile, droughty, or thin soils; also, a plant community that has very sparse cover or is composed of stunted plants. Bedrock Any solid rock exposed at the earth's surface or covered by unconsolidated material such as till, gravel, or sand. Best Management Practices: Methods, measures, or practices to prevent or reduce water pollution, including but not limited to structural and non-structural controls, operation and maintenance procedures, and scheduling of specific activities. Acronym is BMPs. Blowout An area, on a dune or other sand deposit, where wind has eroded abowl-shaped hollow in the sand. Blowouts generally are sparsely vegetated. Bluegreen algae A type of algae whose population often increases dramatically at high nutrient concentrations in lakes. They can form objectionable surface scums, cause taste and odor problems, and secrete toxins poisonous to warm-blooded animals. Bog A wetland composed of a layer of acidic peat on which grows a specialized group of herbs and low shrubs. Bogs are distinguished from closely related poor fens by extremely nutrient- poor conditions and the absence of most of the minerotrophic species that occur in poor fens. Bounce In Hydrologic references, the rise in level in a wetland or lake resulting from a rainstorm event. The difference in elevation between the normal water elevation and the peak water elevation of a pond for a given size runoff event. Brushland An upland plant community composed of shrubs and tree sprouts. Buffer strip: A band of un-maintained, preferably native, vegetation left along the edge of a stream, lake or wetland to filter runoff and/or stabilize the shoreline Calcareous Describes a soil or substrate that contains a significant amount of calcium carbonate. Canopy Aerial branches and leaves of terrestrial plants; generally the tallest layer of foliage in a plant community. Chlorophyll a The primary photosynthetic pigment in plants, a measure of the algal biomass in lakes Colluvium A deposit of rock and soil at the base of a cliff or slope, formed by gravitational action. Colonial nesting birds Species that nest in colonies (groups or aggregations), either with others of the same species or in mixed-species aggregations. Cover The proportion of the ground shaded when the living plant canopy is projected vertically downward; also a general term used to describe any component of the habitat that conceals animals from view. DBH (diameter at breast height) - a standard measure of tree trunk diameter taken approximately 4.5 feet above the ground level. Dominant Describes a plant species that shapes the character of a community by virtue of its size, abundance, dense shade, or effects on soils. Dominant species generally influence the presence, growth, and distribution of other plant species in the community. Degradation A decrease in quality. ~ Many of the definitions used in this section are borrowed from Minnesota's St Croix River Vallev and Anoka Sandolain, Worcha et al, Minnesota DNR, 1995. Top of the World Park Addition Natural Area Management Plan