Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/31/2002
Publication Date: 11/10/2002
Citation: BLANCO-CANQUI, H., GANTZER, C.J., ANDERSON, S.H., ALBERTS, E.E., THOMPSON, A.L. GRASS BARRIERS AND VEGETATIVE FILTER STRIPS FOR SOIL AND WATER CONSERVATION. AGRONOMY ABSTRACTS. 2002. CD-ROM. MADISON, WI. Interpretive Summary:
Technical Abstract: Vegetative grass barriers and filter strips planted in a field offer an opportunity to prevent sediment and nutrient contamination of surface water supplies. The objective of this study was to evaluate the impact of Switchgrass barriers and fescue filter strips both independently and in combination on sediment and dissolved nitrogen concentrations and discharges. The experimental design was a randomized complete block, with 3 blocks. A rotating-boom rainfall simulator was used to apply rain at a rate of 6.4 cm/hr to 1.5-m wide by 11-m long plots on a 3% slope. To adjust for differences in antecedent soil moisture conditions, rainfall was applied for 1 hr on day one of the experiment followed by the same event on day 2. Surface runoff was sampled at 10-min intervals on day 2 to quantify sediment and dissolved N and P concentrations. These results will focus on comparing the relative effectiveness of a 2-m wide strip of switchgrass to a 2-m wide strip of fescue. Switchgrass and fescue strips reduced sediment concentrations by 91 and 82%, respectively, when runoff entering the strips was uniform. As runoff became more concentrated, fescue rapidly lost its ability to remove sediment particles. Switchgrass was also more effective than fescue in decreasing dissolved N concentrations in the runoff. For NO3-N and NH4-N, concentrations were reduced by 58 and 73%, respectively. Switchgrass reduce PO4-P concentrations compared to fescue, but the differences were not statistically significant. Our results show the relative usefulness of grass barriers and filter strips in reducing sediment and dissolved N and P concentrations in surface runoff.