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Ecological systems are dynamic assemblages or complexes of plant and/or animal communities that 1) occur together on the landscape; 2) are tied together by similar ecological processes, underlying abiotic environmental factors or gradients; and 3) form a readily identifiable unit on the ground. These systems provide a coarser level unit than plant associations and alliances as defined under the International Vegetation Classification standard, and are more easily identified on the ground. The descriptions and summarized viability guidelines presented here are intended to serve as a tool for conservation and management planning by providing a context for conservation and management (i.e., what systems do we have in Colorado), and by providing easy access to ranking and evaluation criteria for key ecological attributes of each system (i.e., what is the condition of our systems). System descriptions and viability guidelines are based on materials compiled by NatureServe or developed by the Colorado Natural Heritage Program. Funding for the development of these documents was provided in part by the Bureau of Land Management, The Nature Conservancy, and the USDA Forest Service. Maps were produced using the Southwest Regional Gap Analysis Project landcover dataset. Please note that the extent of each system is exaggerated for display at a statewide scale. Viability specification tables in these documents summarize the factors that contribute to an overall element occurrence (EO) ranking. The estimated viability ranks are: A - excellent, B - good, C - fair, or D - poor. The three primary rank factors (size, condition, and landscape context) are shown in relative order of importance. These factors reflect the present status, or quality of an occurrence and are used as the basis for estimating its long-term viability: 
For ecological systems, the term "viability" is used loosely, since systems are comprised of many separate communities and species, each with their own viability. The viability of an ecological system is considered to be the sum of the viability or persistence of the component communities and their ecological processes. More directly, the ranks usually reflect the degree of negative anthropogenic impact to a community (i.e., the degree to which people have directly or indirectly adversely impacted community composition, structure, and/or function, including alteration of natural disturbance processes). Occurrences of adequate size with relatively few impacts would generally be ranked "A", "B", or "C" (at least "fair" viability, with a high probability of long-term persistence), and those with significant degradation would be ranked "D" ("poor" viability, requiring significant restoration work to enable persistence of the occurrence). Citation for these documents: Central Mixedgrass Prairie (PDF 635 kb) Colorado Plateau Blackbrush-Mormon-tea Shrubland (Not Yet Available) Colorado Plateau Hanging Garden (PDF 676 kb) Colorado Plateau Mixed Bedrock Canyon and Tableland (PDF 1.09 mb) Colorado Plateau Mixed Low Sagebrush Shrubland (Not Yet Available) Colorado Plateau Pinyon-Juniper Shrubland (Not Yet Available) Colorado Plateau Pinyon-Juniper Woodland (PDF 907 kb) Inter-Mountain Basins Active and Stabilized Dunes (Not Yet Available) Inter-Mountain Basins Aspen-Mixed Conifer Forest and Woodland (Not Yet Available) Inter-Mountain Basins Big Sagebrush Shrubland (PDF 827 kb) Inter-Mountain Basins Big Sagebrush Steppe (Not Yet Available) Inter-Mountain Basins Greasewood Flat (PDF 813 kb) Inter-Mountain Basins Interdunal Swale Wetland (Not Yet Available) Inter-Mountain Basins Juniper Savanna (PDF 965 kb) Inter-Mountain Basins Mat Saltbush Shrubland (PDF 784 kb) Inter-Mountain Basins Mixed Salt Desert Scrub (PDF 703 kb) Inter-Mountain Basins Montane Sagebrush Steppe (PDF 1.41 mb) Inter-Mountain Basins Mountain Mahogany Woodland and Shrubland (Not Yet Available) Inter-Mountain Basins Playa (Not Yet Available) Inter-Mountain Basins Semi-Desert Grassland (PDF 826 kb) Inter-Mountain Basins Semi-Desert Shrub-Steppe (PDF 513 kb) Inter-Mountain Basins Shale Badland (PDF 941 kb) Inter-Mountain Basins Wash (Not Yet Available) North American Alpine Ice Field (Not Yet Available) North American Arid West Emergent Marsh (PDF 1.21 mb) Northern Rocky Mountain Avalanche Chute Shrubland (Not Yet Available) Rocky Mountain Alpine Bedrock and Scree (Not Yet Available) Rocky Mountain Alpine Dwarf-Shrubland (Not Yet Available) Rocky Mountain Alpine Fell-Field (Not Yet Available) Rocky Mountain Alpine-Montane Wet Meadow (PDF 1.81 mb) Rocky Mountain Aspen Forest and Woodland (PDF 1.03 mb) Rocky Mountain Cliff, Canyon and Massive Bedrock (PDF 592 kb) Rocky Mountain Dry Tundra (Not Yet Available) Rocky Mountain Dry-Mesic and Mesic Montane Mixed Conifer Forest and Woodland (PDF 648 kb) Rocky Mountain Foothill Limber Pine-Juniper Woodland (PDF 568 kb) Rocky Mountain Gambel Oak-Mixed Montane Shrubland (PDF 921 kb) Rocky Mountain Lodgepole Pine Forest (PDF 943 kb) Rocky Mountain Lower Montane Riparian Woodland and Shrubland (PDF 920 kb) Rocky Mountain Lower Montane-Foothill Shrubland (PDF 0.99 mb) Rocky Mountain Ponderosa Pine Savanna (Not Yet Available) Rocky Mountain Subalpine Dry-Mesic and Mesic Spruce-Fir Forest and Woodland (PDF 970 kb) Rocky Mountain Subalpine Mesic Meadow (Not Yet Available) Rocky Mountain Subalpine-Montane Fen (Not Yet Available) Rocky Mountain Subalpine-Montane Limber-Bristlecone Pine Woodland (PDF 746 kb) Rocky Mountain Subalpine-Montane Riparian Shrubland (PDF 919 kb) Rocky Mountain Subalpine-Montane Riparian Woodland (PDF 1.31 mb) Southern Rocky Mountain Juniper Woodland and Savanna (PDF 827 kb) Southern Rocky Mountain Montane-Subalpine Grassland (235 kb) Southern Rocky Mountain Pinyon-Juniper Woodland (PDF 509 kb) Southern Rocky Mountain Ponderosa Pine Woodland (PDF 1.11 mb) Southwestern Great Plains Canyon (PDF 703 kb) Western Great Plains Cliff, Outcrop, and Shale Barren (PDF 821 kb) Western Great Plains Closed Depression Wetland (PDF 596 kb) Western Great Plains Big River Floodplain (PDF 448 kb) Western Great Plains Foothill and Piedmont Grassland (PDF 966 kb) Western Great Plains Riparian Woodland, Shrubland and Herbaceous (PDF 785 kb) Western Great Plains Saline Depression Wetland (Not Yet Available) Western Great Plains Sand Prairie (Not Yet Available) Western Great Plains Sandhill Shrubland (PDF 943 kb) Western Great Plains Shortgrass Prairie (PDF 900 kb) Western Great Plains Tallgrass Prairie (Not Yet Available) Wyoming Basins Low Sagebrush Shrubland (Not Yet Available) |
