The Delaware Department of Natural Resources and Environmental Control (DNREC) is required to track and report implementation of best management practices (BMPs) for improving soil health and water quality. To meet this need, DNREC has been performing an annual cropland roadside-transect survey for the last 5 years (2014 -2018) to track and evaluate conservation-tillage practices and their implementation. Conducting such surveys is time-consuming and costly, and the utility of these surveys for tracking change has not yet been determined. Sufficient data now exist to determine how tillage practices have changed over time, and to conduct a preliminary analysis of the survey frequency necessary to track that change. However, DNREC lacks staff resources to conduct these analyses.
Once the complete 5-year period dataset has been received, data will be summarized in tables and figures for the whole state of Delaware, for each county, and for each 8-digit hydrological unit (U.S. Geological Survey and U.S. Department of Agriculture, Natural Resources Conservation Service, 2013).
Descriptive statistics will be calculated from transect-sampling points to evaluate: Frequency of cover-crop adoption and coverage
Extent of traditional or commodity cover-crop coverage Frequency and variety of double-cropping practices
Tillage-practice adoption and general residue characteristics BMP implementation changes over time
A sensitivity analysis will be performed to evaluate changes over time in both conservation-tillage and cover-crop adoption. The results from the sensitivity analysis will determine whether the survey results would have yield similar results if the statewide survey had occurred on 2-year or 3-year intervals.
A spatial analysis will be conducted to examine (i.e. plot) the proximity of tillage-observation points against selected existing USGS, DNREC, and DDA water-quality sampling sites to facilitate possible future analysis proposal linking cropping practices to water-quality impacts.
