Buffered stream on farm in Lancaster County.
Row Crop, Pasture, Fodder, Rice, Small Grains
Temperate, Tropical, Semiarid
North America, South Asia, Europe
Nitrogen, Phosphorus, Sediment
Riparian grass buffers are linear strips of grass or other non-woody vegetation maintained between the edge of fields and streams, rivers or tidal waters. They are generally in locations where runoff water leaves a field, with the intention that sediment, organic material, nutrients and chemicals can be filtered from the runoff water. Buffer vegetation can improve soil aeration, lessen water quality degradation by nutrient removal in the root zone by plant uptake and sorption to soil, and provide wildlife habitat. The efficiency of buffer zones in removing suspended solids and nutrients is affected by the width of the zone, gradient of the drained field, soil type and particularly by the variety and density of zone vegetation.2
For either grass or tree buffers, width is the most important criteria. 10 m width should be considered as the goal. If land is limited, smaller width buffers are better than no buffer even though they have reduced efficiency. Establishment of buffers requires taking land out of crop production. But there are opportunities for harvesting fodder crops; Cost of establishing grass buffer low but it requires moderate maintenance costs. Over the long term, buffers are very cost effective practices in terms of dollars per pound of nutrient reduced.
Scalable to small farms?
Protected vegetated zones that are harvested for fodder have the potential to increase biomass compared to overgrazed streamside pastures.
1 "Documentation: Source Data, BMP Effectiveness Values." Chesapeake Assessment Scenario Tool. Web. 2013. http://casttool.org/Documentation.aspx .
2 Estimates of County-level Nitrogen and Phosphorus Data for Use in Modeling Pollutant Reduction Documentation for Scenario Builder Version 2.2." Chesapeake Bay. Dec. 2010. Web. May 2013. http://archive.chesapeakebay.net/pubs/SB_V22_Final_12_31_2010.pdf.; "EU Database of Best Practices." Living Water Exchange: Promoting Replication of Good Practices for Nutrient Reduction and Joint Collaboration in Central and Eastern Europe. Web. Sept. 2013. http://nutrient2.iwlearn.org/nutrient-reduction-practices/eu-database-of-practices/view.