Managing Global Resources for a Secure Future

2017 Annual Meeting | Oct. 22-25 | Tampa, FL

334-5 Potential Soil Carbon Mineralization and Mineralization Kinetics Under Diverse Cover Crop Residues.

See more from this Division: SSSA Division: Soil Biology and Biochemistry
See more from this Session: Surface Residue Management and Impacts on Soil Biology and Soil Health

Wednesday, October 25, 2017: 9:05 AM
Tampa Convention Center, Room 22

Binod Ghimire, Entomology, Plant Pathology, and Weed Science department, New Mexico State University, Las Cruces, NM, Rajan Ghimire, Agricultural Science Center, New Mexico State University, Clovis, NM, Abdel O. Mesbah, New Mexico State University, Clovis, NM and Dawn VanLeeuwen, Applied Statistics & International Business, NMSU, Las Cruces, NM
Abstract:
Global warming and environmental degradation associated with agriculture raise concern on how alternative agricultural practices can improve in soil organic matter cycling and agroecosystem resilience. This study aims to estimate soil organic carbon (SOC) mineralization and their kinetics under different residue management. A laboratory incubation study was conducted on soil samples manipulated with three rates (0, 5 and 10 Mg ha-1) of pea (P), oat (O), and canola (CN) residues. Two kinetic models were fitted to observe SOC mineralization data for estimating labile organic carbon (C0), and decomposition rate constants (k) for CC residues amended soils. The best model was selected based on AICC, RMSE, NRMSE, and r-value. The CC residues stimulated cumulative SOC mineralization (Cmin) irrespective of CC type and rate of residue addition. Doubling the rate of CC residue addition increased Cmin by 74%, 93% and 73%% for CN, P and O, respectively. The C0 varied with the residue amount while k varied with CC type. The C0 was 297% to 858% greater with 10 Mg ha-1 and 297% to 456% greater with 5 Mg ha-1 residue addition while k was 122% to 297% greater with 10 Mg ha-1 and 94% to 240% greater with 5 Mg ha-1 residue addition compared to the treatment with no residue addition. The CC residues can increase SOC cycling in agroecosystems.

See more from this Division: SSSA Division: Soil Biology and Biochemistry
See more from this Session: Surface Residue Management and Impacts on Soil Biology and Soil Health