Wetland Vegetation Response to the Restoration of Sheet Flow at Cheyenne Bottoms, Kansas

摘要

The restoration of inland salt-affected plant communities, including saltflat mixed prairie and playa lakes wetlands, has received little attention despite the importance of these communities for critical wildlife habitat. The salt-affected communities of Cheyenne Bottoms, located in central Kansas, are a crucial stopover site for migratory waterfowl and shorebirds. In 1998, The Nature Conservancy attempted to restore native plant communities to grazed and former cropland at Cheyenne Bottoms by reestablishing sheet flow across these disturbed areas. We collected vegetation cover data along permanent transects established in rangeland, former cropland, and in a shallow basin 3 years (1996-1998) before the hydrological changes and continued to collect vegetation data for 3 years (1999-2001) after the hydrological changes. Vegetation composition changes in response to the restored hydrology were subtle, but the average wetland index along the transects in the basin and the rangeland significantly declined. Significant decreases occurred in the cover of perennials and graminoids in both spring and fall species assemblages of the rangeland area. Changes in the former cropped areas were mixed, indicating the difficulty of restoring these disturbed plant communities to native plant assemblages within a few years.