Abstract:
Increased water demand and frequency of droughts, due to climate change in india, has led to water scarcity in the domestic and agricultural sectors. In such scenarios, small scale and decentralised water infrastructures, for example, check dams, have reduced water demand extremes and climate change impacts on water resources, especially for marginalised and low income farmers in semi-arid regions. This study aims to quantify the impact of a network of check dams on increasing soil moisture (sm) and crop productivity (cp) in a semi-arid indian region. As a case study, 52 check dams were mapped, from 1990 to 2017, across the dahod district of gujarat state, and increases in sm and cp were quantified using remote sensing data-based indicators, including normalised difference vegetation index (ndvi) and normalised difference water index (ndwi). Results indicate an overall increase in ndvi from −0.2 to 0.1, and ndwi from 0.03 to 0.3, indicating an increase in vegetation cover and water content, respectively. In addition, spatiotemporal analysis indicates that the locations near the check dam had rapid increase in both indicators, and less dependence on rainfall variability. The study showed that remote sensing based indicators have been useful in documenting the impact of water recharge structures, especially in ungauged basins. However, it is important to use remote sensing data along with observation data for better accuracy of assessments. Results also indicate that the check dams could have been important in increasing water resource availability, as impact of other water resources is yet unknown in the region. Increased water resources, through improved sustainable development of water infrastructure, have increased the vegetation and decreased the vulnerability to climate change extremes, and thereby increased the socio-economic status of marginalised farmers in dahod. © 2021 united nations.