Johnson et al., 2016). Removal of crop residue reduces soil organic carbon (SOC), and impacts soil productivity. However, the impacts of residue removal rates on soils depend on certain factors such as soil texture, soil topography, initial contents of SOC, tillage, and cropping system (Blanco-Canqui et al., 2013). Water is the most limiting factor for crop production in regions where either irrigation is not available or precipitation is limited (Das et al., 2017). Water stored in the soil profile helps to fulfill the water requirement for following crop in the rotation. Corn residue left behind after corn harvest helps to conserve water in soil (Iqbal et al., 2013) and plays an important role in water conservation and hence increase grain yields where irrigation or precipitation is a limiting factor in crop production (Van Donk et al., 2010; VanLoocke et al., 2012). The long-term adoption of CC could negate the adverse effects of residue removal and increase SOC and improve soil water dynamics, eventually improving crop production and soil productivity (Basche et al., 2016a; Basche et al., 2016b; Kahimba et al., 2008). A study by Chahal and Van Eerd (2018) showed that cover crop increased SOC concentrations by 8.4 to 9.3% and crop yield by 7.9 to 22% compared with no cover crop treatment. Basche and DeLonge (2017) showed that adoption of CC for more than 10 yr improved soil hydrological properties

The objective of this study was to investigate the ability of on-farm water storage (OFWS) systems to mitigate off-site nutrient movement in a south-central U.S. agricultural watershed. We examined the seasonal water quality changes in an OFWS system by measuring several physical and chemical constituents at multiple sampling points throughout the system. Water quality sampling occurred every three weeks during the growing season and every six weeks during the dormant season from February 2012 to December 2014. The collected data were grouped into four seasons and then analyzed using boxplots along with the Wilcoxon and Kruskal-Wallis rank-sum tests for detecting changes in nutrient concentrations. Significant water quality changes were observed in the OFWS system by season and nutrient species, indicating a variation in downstream nutrient reduction with season. The in-ditch median removal efficiency, from the center of the tailwater recovery ditch to the outlet, was 54% during winter and 50% during spring for NO 3-N; 60% during spring for NH 3-N; 26% during autumn and 65% during winter for ortho-P; and 31% during winter and 10% during spring for TP. The in-pond median concentration removal efficiency was ~77% during summer for NO 3-N, while the concentration remained stable during winter, spring and autumn; 53% from winter to spring and 58% from spring to summer for NH 3-N; 70% from winter to spring for ortho-P, while remaining stable during the other seasons; and 28% from winter to spring and 55% from spring to summer for TP. Our results support the hypothesis that OFWS systems could mitigate downstream nutrient-enrichment pollution, especially during spring. The results obtained from this study offer a better insight into the behavior of OFWS systems and help enhance the management of agroecosystems from an ecological and hydrological perspective for water quality pollution control and water resource conservation.

No abstract

No abstract

Land use land cover (LULC) and climate are the determinant factors for the soil water balance. The combined effect of LULC and climate change is of great importance for effective water resources planning and management. This study assessed the hydrological impact of long‐term implementation of integrated crop‐livestock (ICL) system with the projected climate scenarios on water yield using the Soil and Water Assessment Tool model over two time periods (i.e., near future [2021–2050] and far future [2070–2099]). This study was conducted in three phases over Skunk Creek watershed (SCW), South Dakota. In phase I, the impact of long‐term ICL system implementation (1976–2005; 30 years) on soil hydrology was evaluated. Phase II and phase III evaluated the impacts of projected climate changes under existing land cover and ICL system, respectively. Outcomes of phase I showed a significant decrease in water yield and surface runoff. Phase II showed the susceptibility of SCW to extreme events such as floods and waterlogging during spring, and droughts during summers under the projected climate changes. Phase III showed the reduction in water yield and surface runoff due to the ICL system and minimizing the induced detrimental impacts only due to climate change. This study provides a perspective on the possible impacts of the ICL system to mitigate the hydrological alteration due to climate change.