Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: April 5, 2002
Publication Date: April 18, 2002
Citation: Vadas, P.A., Meisinger, J.J. 2002. Development of the phosphorus leaching component of maryland's phosphorus site index. BARC Poster Day.
In Maryland, the loss of phosphorus (P) from agricultural soils has been identified as a major cause for the decline of water quality in the Chesapeake Bay. To decrease this P loss, Maryland's Water Quality Improvement Act requires nutrient management plans for virtually all farms. The Phosphorus Site Index (PSI) is an integral part of a nutrient management plan. The PSI considers a number of factors that contribute to P loss, including a soil leaching potential determined by an NRCS rating based on inherent soil characteristics. We are currently conducting research on Maryland's Lower Eastern Shore to determine if the method used by the PSI to determine a soil's leaching potential is adequate or even applicable to all scenarios. We instrumented two field sites on a University of Maryland research farm at Poplar Hill to quantify the sites' hydrologic characteristics and to investigate the P leaching under various hydrologic scenarios. We conducted slug tests to estimate saturated hydraulic conductivity (K), which ranged from 0.05 m/d to 19.9 m/d. We related K values to soil properties, with the best relationship observed between effective horizontal K values and the depth to redoximorphic features in the soil. We also present preliminary detail of our methods to investigate P leaching at the field sites.