2007 Annual Report
A Postdoctoral Research Associate was hired in January 2007 to manage and co-ordinate project related research activities. Various project related activities and procedures were discussed, finalized and implemented in part using conference calls (September 2006) and one-to-one meetings (June, August, and September 2006, and in February and May 2007). In addition there were several trips made to the different research sites in PA and MD.
Research projects to address the objectives mentioned below have been initiated in the Mahantango watershed located in east-central Pennsylvania and the Choptank river watershed which feeds directly into the main stem of the Chesapeake Bay and is the only tidal watershed under study in the CEAP program.
• Relate topography to nitrogen (N) fertilizer recommendations: Corn yield response to N fertilizer applications was observed to co-vary with soil moisture as related to topographic position. LiDAR may be used to generate detailed topographic maps for the purpose of refining N fertilizer recommendations. • Determine N availability for corn along a transect from drier to wetter landscape positions in a Delmarva Bay agricultural landscape. • Detect Rill Erosion: Test the maximum vertical resolution of LiDAR for use in mapping rill erosion as an indication of variable source area runoff following a major rainfall event. • Accurately delineate watershed boundaries. The watershed boundaries will then be used to define contributing areas for water quality sample analysis and landscape and water quality models. • Locate areas of potential and actual water accumulation (flooding). This information will be used to estimate wetland services (e.g. pollutant removal, habitat, and flood mitigation). • Delineate overland flow pathways which will be used to better define the linkage between agricultural fields and adjacent wetlands.
LiDAR and color-infrared imagery data were collected for the WE-38 (March 26, 2007) watershed in the Mahantango watershed and the Choptank area (March 28, 2007) using an aircraft-mounted Optech ALTM 3100 sensor, which can fire up to 100,000 laser pulses per second. The ALTM 3100 system records four hits from each of the laser pulses, meaning that elevation information will be gathered not only for the ground but for surface features as well.