2012 Annual Report
1a.Objectives (from AD-416):
Determine effects of crop residue removal on soil quality, crop yields, and residue feedstock quality.
1b.Approach (from AD-416):
On-going studies at the USDA-ARS-CPRC and at the Clemson University, Pee Dee Research and Education Center (PDREC) will be enhanced by providing additional analyses for improving soil quality, enhancing crop yields, and assessing the suitability of crop residues as feedstocks for thermal chemical conversion. More information will be gathered on residue removal influences on profile soil physico-chemical properties, changes in crop yield and grain quality, and ascertaining residue quality as a feedstock for thermal chemical conversion. This study will complement the ARS Renewable Energy Assessment Project (REAP) team efforts with similar resources at eight participating ARS locations. Equal resources per the SunGrant program are available to university partners (i.e., PDREC) to strengthen the research, provide additional agronomic expertise, and improve technology transfer products and relationships with customers.
This five-year project relates to inhouse project objective 2b: by examining the impact of removing different fractions of corn biomass from small plots on subsequent crop yields, crop elemental composition, thermal energy equivalents, and soil chemical/physical properties. This is the final report for 6657-12130-002-01R; work will continue on 6657-12130-002-07R.
There is much interest among the industrial processing sector in utilizing corn residue for biofuel production, but sustainable biomass removal amounts for sandy soils is unknown. Results have been amassed and data interpreted from the 4th corn crop cycle. The corn crop was under stress from unusually high June and July temperatures and marginal monthly rainfall totals. Corn yields and biomass yields were far below average mostly due to climate variability. Topsoil potassium concentrations after four years are declining due to nutrient removal from harvested corn residue. This implies that fertilizer management practices in fields losing crop residues may need to be modified to account for nutrient replacement.