Submitted to: Journal of Soil and Water Conservation
Publication Type: Popular Publication
Publication Acceptance Date: 9/14/2009
Publication Date: 12/15/2009
Citation: McCarty, G.W., Hively, W.D., Keppler, J. 2009. Federal-State partnership yields success in remote sensing evaluation of conservation practice effectiveness: Results from the Choptank river CEAP. Journal of Soil and Water Conservation. 64:154A. Interpretive Summary:
Technical Abstract: The use of winter cover crops to sequester residual soil nitrogen (N) following the summer row-crop growing season has been identified as an important and successful conservation practice in the Chesapeake Bay watershed. Nitrogen losses to groundwater are reduced during the winter season, provided that cover crop management strategies and climate conditions lead to sufficient growth and nutrient uptake prior to the onset of winter. USDA-ARS scientists have partnered with the Maryland Department of Agriculture (MDA) to evaluate the effectiveness of on-farm cover crop program implementation in protecting water quality. This ongoing Federal – State partnership has developed over the course of four years of research activities, supported by NRCS and ARS funding under the Choptank River watershed Conservation Effects Assessment Project (CEAP). Each fall, MDA provides a list of all fields enrolled in the Maryland Cover Crop Program within the Choptank River Watershed, a subset of which are subsequently sampled by ARS scientists at the time of satellite imagery acquisition: once in December to measure N uptake prior to the onset of winter, and once in March to estimate springtime nutrient uptake prior to row-crop planting. From these data, observed aboveground biomass measurements are correlated with satellite-derived reflectance data to derive biomass and N uptake estimates for all fields enrolled in the cover crop program. From this data, actual conservation program dollars spent per pound of N sequestration can be calculated on a county, watershed, or regional basis.