Impact assessment of indigenous field-level water storage structure (diggi) on agriculture in the great Indian desert

摘要

In the arid region of Rajasthan, India, it is very often a challenge to store rain/surface water for year-round use by human and livestock. The inhabitants of this desert area have developed several water storage structures, which they used to construct based on their indigenous knowledge of local terrain conditions. Recently, farmers living in the lower command areas of Indira Gandhi canal have constructed micro-farm water storage structures, called diggi, in their cropland. They store allocated canal water in diggi to timely utilize it as per irrigation requirements, and thus, done away with problems of deficit and untimely canal water supply. This impact assessment study, carried out in Poogal tehsil of Bikaner district, analyzed high-resolution satellite images for 2 years and used a geographic information system to quantify diggi structures and studied the diggi-growth interactions with changing rainfall pattern as well as land use/land cover. Results showed that during 2018, about 3243 number of structures were constructed compared to 241 existed during 2004-2005. The mean annual rainfall increased by 30% and crop area by 12,772 ha during the same period that included 7.86% increase in irrigated and 2.98% in rainfed croplands. Thus, diggi-based water management has been immensely helpful in the perspective of irrigated agriculture in the desert region.