Spatio-temporal variations in irrigation development: evidence from a semi-arid region of Rarh Bengal, Eastern India

Irrigation, along with a high-yielding variety of seeds and chemical fertilizer, is a crucial component of contemporary agricultural technology for enhancing yield in a semi-arid agrarian region of Rarh Bengal. The investigation aims to determine the spatio-temporal disparity in irrigation intensity, the source-wise irrigation utilization index (IUI), and the cumulative annual exponential growth rate (CAEGR) of irrigation in the study region from 2009-2010 to 2017-2018 and also tries to find out the link between irrigation intensity (II) and source-wise irrigation utilization (IUI) using Karl Pearson's product-moment correlation coefficient, linear regression analysis, and residual mapping through the Ordinary least squares method. Irrigation intensity is mostly concentrated in the eastern and south-eastern areas, as opposed to the dry, upland western and north-western districts. The district's net irrigated area has a significantly positive CAEGR (+ 3.34); however, at the block level, there is a downward tendency in both the river lift and other irrigated areas. The study also explores a considerable association between the source-wise IUI and II [F (5,16) = 25.341, p < 0.001]. Canal IUI, being the dominant source of surface irrigation, proved to be inevitable for the irrigational development of the entire study domain (B = 46.724, t = 7.383, p <= 0.001) and (B = 48.202, t = 6.850, p <= 0.001), which accounts 72.09% and 80.61% variation in II in both years. Finally, to maintain the sustainability of irrigation, effective management of water has become a concerning issue in this semi-arid region of Rarh Bengal. Therefore, the minor surface irrigation schemes along with the conservation of traditional irrigation and water harvesting systems as an alternative irrigation management approach are becoming increasingly important for future irrigation development.