Spatio-temporal variation and relationship between agricultural efficiency and irrigation intensity in a semi-arid region of India

A surging population in Karnataka State, a semi-arid region in India, poses a threat to both food security and livelihood sustainability, necessitating a concentrated effort to bolster agricultural efficiency and achieve United Naton's Sustainable Development Goal 2 (zero hunger). Therefore, in order to address the pressing issue of food scarcity in Karnataka, this study meticulously examined the spatio-temporal variation of agricultural efficiency and irrigation intensity in Karnataka, uncovering its significant dependence of agricultural efficiency on irrigation intensity. Specifically, this study used a one-way analysis of variance (ANOVA) to ascertain significant differences in the means of agricultural efficiency and irrigation intensity during 2004–2005 and 2018–2019. This study showed that the maximum improvement in agricultural efficiency index was recorded in Belgaum (40.24), Gulbarga (24.77), and Yadgir districts (22.92) between 2004–2005 and 2018–2019, which indicated the progressing trend and better scope for agriculture extension. On the contrary, some districts expressed threat (a decline of above 20.00 of agricultural efficiency index) and needed special care for the improvement of agricultural efficiency in four northern districts (Bagalkot, Bidar, Raichur, and Bijapur), three southern districts (Chitradurga, Chikballapur and Hassan), and two southern districts (Koppal and Gadag) in Karnataka. During 2004–2005, irrigation intensity varied from 3.19% to 56.39%, with the lowest irrigation intensity in Kodagu District and the highest irrigation intensity in Shimoga District. During 2018–2019, irrigation intensity changed from 0.77% to 72.77%, with the lowest irrigation intensity in Kodagu District and the highest in Dakshin Kannad District. Moreover, the research scrutinized the complex relationship between agricultural efficiency and irrigation intensity, with the correlation coefficient increased from 0.162 during 2004–2005 to 0.255 during 2018–2019. It implies that in both periods, a low positive correlation existed between these two variables. Over time, several factors (high-yield seeds and chemical fertilizers) other than irrigation intensity gradually became essential for agricultural efficiency. This research offers a wealth of valuable insights for regional planners and policy-makers contending with comparable challenges in various regions of India and other developing countries.