Author
Submitted to: Eastern Native Grass Symposium
Publication Type: Proceedings Publication Acceptance Date: 11/17/1999 Publication Date: N/A Citation: Schnabel, R.R. 1999. Improving water quality using native grasses. Eastern Native Grass Symposium. p. 46-54. Interpretive Summary: Thousands of miles of streams and thousands of acres of lakes and estuaries in the eastern U.S. do not fully meet the water quality standards of their designated uses. The most common causes of impairment were excessive levels of sediment, plant nutrients, and pathogens. To bring these waterbodies into compliance, as required by the Clean Water Act, the level of pollutants in the watershed, or their transport to the stream, must be controlled. Many efforts to improve water quality will require choices of vegetation. Research indicates that native grasses can be used and should be considered during planning and implementation of water quality improvement projects. Native grass buffers limit the transport of nonpoint source pollutants within and from fields. Vegetative barriers of switchgrass and gamagrass commonly trap 50% or more of coarse sediment and significant amounts of plant nutrients within fields. Grassy riparian buffers, either alone or in a forested buffer system, trap or transform sediments and plant nutrients before they enter streams. Native grasses might also be used in contour filter strips that can retain 50-70% of nutrients, pathogens, and sediment. Incorporating perennial, native warm- season grasses into farming systems and seeding them in critical areas further reduces erosion and loss of plant nutrients. Native warm-season grasses produce large amounts of biomass suitable as forage or biofuel feedstock with fewer inputs than other vegetation. Their incorporation into farming systems can reduce inputs to the farm and the potential for their loss. Native grasses have a place in efforts to improve water quality, both in limiting the source of pollutants and intercepting pollutants before they enter a waterbody. Technical Abstract: Many water quality challenges exist in the eastern U.S. Thousands of miles of streams and thousands of acres of lakes and estuaries do not fully meet the water quality standards of their designated uses. The Clean Water Act requires states to devise and implement plans to bring these waterbodies into compliance. The Chesapeake Bay States agreed, by 2000, to reduce the mass of pollutants entering the Bay 40% below 1985 levels and then cap the at that level. Concurrently, the USDA has started a program to establish 2 million miles of conservation buffers by 2002. Efforts to improve water quality will require choices of vegetation. Native grasses should be considered for water quality improvement projects. Native grass buffers limit the transport of NPS pollutants within and from fields. Vegetative barriers of switchgrass and eastern gamagrass commonly trap up to 50% of coarse sediment and significant amounts of plant nutrients within the field. Grassy riparian buffers, alone or as part of a forested buffer system, trap or transform sediments and plant nutrients before they enter streams. Native grasses might also be used in contour filter strips that can retain 50-70% of nutrients, pathogens, and sediment. Incorporating perennial, native, warm-season grasses into farming systems and seeding them in critical areas further reduces erosion and loss of plant nutrients. Native warm-season grasses produce large amounts of biomass suitable for forage or as biofuel feedstock with less fertilizer than other vegetation. Their incorporation into farming systems can reduce inputs to the farm and the potential for their loss. Native grasses have a place in efforts to improve water quality, both in limiting the source of pollutants and intercepting pollutants before they enter a waterbody. |