|CHALISE, K - South Dakota State University|
|SINGH, SHIKHA - University Of Tennessee|
|WEGNER, BRIANNA - Natural Resources Conservation Service (NRCS, USDA)|
|KUMAR, SANDEEP - South Dakota State University|
|GUTIERREZ, JUAN - South Dakota State University|
|NLEYA, THANDIWE - South Dakota State University|
|GUZMAN, JOSE - South Dakota State University|
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/14/2018
Publication Date: 9/13/2018
Citation: Chalise, K.S., Singh, S., Wegner, B., Kumar, S., Gutierrez, J.P., Osborne, S.L., Nleya, T., Guzman, J., Rohila, J.S. 2018. Cover crops and returning residue impact on soil organic carbon, bulk density, penetration resistance, water retention, infiltration, and soybean yield. Agronomy Journal. 110:1-10.
Interpretive Summary: Crop residue removal rate from US farm lands has increased in recent years due to short-term economic benefits. Crop residues protect soil from surface sealing and compaction, and help in building soil organic matter and enhancing the water retention. However, little is known about the role of crop residues and cover crops on soil properties and soil-water dynamics in soybean production. A three year study was conducted with two residue removal treatments: low residue removal (LRR) and high residue removal (HRR) following a no-till corn/soybean rotation along with two cover crop treatments: cover crops (CC) and no cover crops (NCC). This study showed that LRR treatment lowered soil bulk density (BD), reduced soil penetration resistance (SPR), increased soil organic carbon concentration, total nitrogen and increased soil water infiltration (SWI) compared to HRR. Similarly, the CC treatments resulted in lower soil BD, lower SPR, and increased SWI. A significant impact of crop residues was also observed on soil water retention. Further, the LRR and CC treatments increased the soil volumetric moisture content and soil water storage. Interestingly, CC treatments increased the soybean yield by 14% and water use efficiency by 13% compared with NCC treatment. Data from this study showed that use of cover crops with LRR improves soil properties, soil water retention, and soybean yield. These cultural practices will help conserve and more effectively utilize water resources for soybean production.
Technical Abstract: Cover crops (CC) and crop residue (CR)-removal (CRR) affect soil properties, but limited information is available on their impacts in the Northern Great Plains region (NGR) of the USA. A study was undertaken at Brookings, South Dakota, which has fine-silty, mixed, superactive, frigid, Calcic/ Pachic Hapludolls soils to understand the impact of long term CC and CR on soil properties and soil-water dynamics for soybean (Glycine max L.) crop in rotation with corn (Zea mays L.). The study had two CRR treatments [low residue removal (LRR), high residue removal (HRR)], and was established in 2000 under a no-till corn /soybean rotation using a randomized complete block design. Starting in 2005, the CRR treatments were subdivided to include CC and no CC (NCC). In 2014 the current investigation was initiated and repeated in 2015 and 2016. The data showed that the LRR treatment lowered soil bulk density (BD) and soil penetration resistance (SPR) compared to HRR in all three years viz, 2014, 2015 and 2016. In addition, the LRR treatment also increased soil organic carbon concentrations and total nitrogen by 22 and 17%, respectively, compared to that of HRR. The LRR significantly increased soil water infiltration by 66% and 22% compared to HRR in 2014 and 2015, respectively. The CC resulted in lower BD and SPR by 7% and 23%, respectively compared to NCC treatment. Further, the CC increased soil water infiltration by 82 and 22% compared to the NCC in 2014 and 2015, respectively. A significant impact of CR was also observed on soil water retention in 2014 and 2015. The LRR and CC treatments increased the soil volumetric moisture content and soil water storage. Overall, the CC treatment significantly increased soybean yield by 14% and water use efficiency by 13% compared to NCC treatment. Data from this study showed that the use of CC with LRR can enhance soil moisture conservation and soybean yield in NGR.