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Agricultural water management (AWM) interventions play an important role in ensuring sustainable food production and mitigating climate risks. This study was carried out in a watershed located in a low rainfall (400-600 mm) region of western India. The Soil and Water Assessment Tool model was calibrated using surface runoff, soil loss, and reservoir storage levels, between the year 2000 and 2006. The investigation indicated that the various AWM interventions increased groundwater recharge from 30mm/year to 80 mm/year and reduced surface runoff from 250 mm/year to 100 mm/year. The intervention structures were refilled two to three times during the monsoon season depending on rainfall intensity and duration. The interventions have the advantage of building a resilient system by enhancing groundwater availability even in dry years, stimulating crop intensification and protecting the landscape from severe erosion. The results indicate that soil erosion has been reduced by more than 75% compared to the nonintervention situation. Moreover, the AWM interventions led to the cultivation of 100-150 ha of fallow land with high-value crops (horticulture, vegetables, and fodder). Household income increased by several folds compared to the nonintervention situation. The study showed about 50% reduction in downstream water availability, which could be a major concern. However, there are a number of ecosystem trade-offs such as improved base flow to the stream and reduction in soil loss that should be considered. The study is of great importance to stakeholders to decide on the optimal design for AWM interventions to achieve sustainable development goals. [ABSTRACT FROM AUTHOR]

A host of best water and soil management practices (BMPs) hold promise in addressing water scarcity and land degradation to enable sustainable crop intensification in smallholder farming systems. OBJECTIVE This study quantifies the effect of BMPs on crop productivity, income, water saving and water balance components and identifies gaps for future research. This paper synthesizes the performance of BMPs and the existing data gap by reviewing 108 published studies from the Indian subcontinent which capture a diverse range of rainfall and cropping systems. In situ conservation measures helped enhance crop yields by 200–1000 kg/ha, reduced cost of cultivation and enhanced incomes by US$ 10–200/ha/year. The BMPs were helpful in enabling annual water saving in the range of 50 mm to 300 mm by either conserving residual soil moisture or saving irrigation water resulting in enhanced water productivity. Interventions such as direct seeded rice and laser land leveling were found most effective in terms of water saving and in reducing cost of cultivation. On the other hand, ex situ rainwater harvesting interventions helped enhance groundwater recharge by harvesting an additional 50–150 mm of surface runoff which helped increase crop yields, led to sustainable crop intensification and strengthened the number of ecosystem services. Most of the published literature on in situ conservation measures are studies that were carried out at research stations, which show promise of sustainable intensification. However, greater efforts are needed to document learnings from farmer/community scale interventions for effective scaling up. There is also a gap in data availability that hampers a clear understanding of the impact of ex situ rainwater harvesting interventions and ecosystem trade-offs; moreover the data available covers short periods and only covers an area of up to 10 km2. We recommend the monitoring of long-term system-level impact indicators to realize the potential of ex situ rainwater harvesting interventions in a systems perspective and better grasp the ecosystem trade-offs. More importantly, the review revealed the ample scope of integrating in situ and ex situ interventions to build system-level resilience in smallholder farming systems in order to accelerate progress towards achieving the United Nations Sustainable Development Goals (SDGs). [Display omitted] • Direct seeded rice and laser land leveling interventions can reduce irrigation water requirement by 200–300 mm • Raised bed and mulching are found helpful to conserve 50–80 mm moisture • Ex-situ rainwater harvesting interventions enhanced groundwater availability by harvesting 50–150 mm surface runoff • Integration of in-situ & ex-situ practices hold promise to bridge the yield gap while ensuring sustainable intensification [ABSTRACT FROM AUTHOR]