Document: GWE-3-40-42

A classification of riparian wetland plant associations of Colorado.

KITTEL, G.M.* ¹ and R.J.RONDEAU ²

The Nature Conservancy Western Resource Office, Boulder, CO 80302 ¹
Colorado State University, Fort Collins, CO 80523 ²

Abstract:
A classification of riparian plant associations for Colorado was developed to understand riparian vegetation diversity and functionality. The nine year project designed a comprehensive, field-based, classification of riparian wetlands. Between 1990 and 1999, over 1880 quantitative plots were collected using a systematic, stratified-random site selection approach and consistent field data collection on USGS designated perennial and ephemeral streams. 150 native plant associations were described, including conifer forests, deciduous woodlands, willow shrublands, non-willow shrublands, herbaceous meadows, alkaline flats, acidic fens, and alpine peatlands. Riparian areas dominated by non-native species were not described. Sampling occurred on public and private land. Results indicate the classification covers an estimated 80-90% of Colorado's riparian wetland diversity. Some plant associations are very rare and unique to Colorado, others are quite common, known from literately hundreds of streams. While Colorado's riparian areas cover less than 3 percent of the land area in the state, they house over 40% (1220 taxa) of the known plant species in the State. Of the 150 riparian plant associations, 43 (29%) are ranked G1 to G2-critically imperiled to imperiled globally; 49 (32%) are ranked G3-vulnerable, and 58 (38%) are ranked G4 to G5-apparently to demonstrably secure globally.

Keywords: Riparian vegetation, classification, conservation, biodiversity

This abstract is being presented at: 9:45 AM in session:
Oral Session #59: Plant Communities: Vegetative Analysis.