Full ecoregional plan - Conservation Gateway

Representativeness: Captures multiple examples of all conservation targets across thediversity of environmental gradients appropriate to the ecoregion (e.g., ecoregionalsection or subsection, ecological land unit (ELU), or some other physical gradient).Section : Areas of similar physiography within an ecoregional province; a hierarchicallevel within the USDA Forest Service ECOMAP framework for mapping andclassifying ecosystems at multiple geographic scales.Shifting Mosaic: An interconnected patchwork of distinct vegetation types that may shiftacross the land surface as a result of dynamic ecosystem processes, such as periodicwildfire or flooding.Site (or Conservation Site, or Portfolio Site) : Areas that are defined by the presence ofconservation targets, are the focus of conservation action, and are the locus formeasuring conservation success.SLOSS : Acronym standing for “single large or several small” referring to a long-runningdebate in ecology and conservation biology as to whether it is more effective forbiodiversity conservation to have a single large reserve or several small reserves.Small Patch: Communities that form small, discrete areas of vegetation cover. Individualoccurrences of this community type typically range in size from 1 to 50 hectares. Smallpatch communities occur in very specific ecological settings, such as on specializedlandform types or in unusual microhabitats. The specialized conditions of small patchcommunities, however, are often dependent on the maintenance of ecological processesin the surrounding matrix and large patch communities. In many ecoregions, smallpatch communities contain a disproportionately large percentage of the total flora, andalso support a specific and restricted set of associated fauna (e.g., invertebrates oramphibians and reptiles) dependent on specialized conditions.Spatial Pattern: Within an ecoregion, natural terrestrial communities may be categorizedinto three functional groups on the basis of their current or historical patterns ofoccurrence, as correlated with the distribution and extent of landscape features andecological processes. These groups are identified as matrix communities, large patchcommunities, and small patch communities.Stratification: A hierarchical division of an ecoregion into nested, progressively smallergeographic units. Spatial stratification is used to represent each conservation targetacross its range of variation (in internal composition and landscape setting) within theecoregion, to ensure long-term viability of the type by buffering against degradation inone portion of its range, and to allow for possible geographic variation.Stream Order: A hierarchical ordering of streams based on the degree of branching. Afirst-order stream is an unforked or unbranched stream. Two first orders flow togetherto make a second order; two second orders combine to make a third-order stream.Stress: Something which impairs or degrades the size, condition, or landscape context ofa conservation target, resulting in reduced viability.Subsection : Areas of similar geologic substrates, soils and vegetation within anecoregional section; a level within the USDA Forest Service ECOMAP framework formapping and classifying ecosystems at multiple geographic scales.UPDATED 6/2003GLOS-7