ASSESSMENT OF YIELD GAP AND IMPACT OF CLIMATE CHANGE ON WHEAT CROP IN UTTARAKHAND DISTRICTS: A COMPREHENSIVE ANALYSIS AND ADAPTIVE STRATEGIES

Abstract

Global food demand is increasing as the population is increasing. More food is needed to feed the increased population, and crop yield should be increased. To increase agricultural production, there are two ways: to increase the crop area or to increase the crop yield per unit area from present agricultural land. The first alternative to increasing food production is not a sustainable way to increase crop production. The only possible sustainable way to increase crop production is by increasing the crop yield per unit area. This can be achieved only after decreasing the crop yield gap. In the present study, a calibrated DSSAT-CERES wheat model was used to simulate the wheat yield under an optimum irrigation scenario to get potential yield and under a limited irrigation scenario to get a water-limited yield, for each district of the Uttarakhand state from 2000 to 2020. In the hilly region of Uttarakhand, the mean total yield gaps found was 0.15 t ha−1 in all the districts from the 2000 to 2020 years. Almora experienced a 0.51 t ha−1 average maximum total yield gap, and it emerged as a district consistently experiencing total wheat yield gaps throughout the entire study period from 2000 to 2020. This indicates potential challenges or limitations in wheat production practices in Almora, which may require further investigation and targeted interventions to address. On the contrary, Bhageswar and Dehradun districts demonstrated more stable performance, with no or very low total yield gaps observed throughout the study period. Further information was gained from the analysis of water-limited wheat yields in the hilly region of Uttarakhand State. Pauri Garhwal district stood out with the highest recorded yield gap of 2.69 t ha-1 in 2008, indicating wheat yield is sensitive to the irrigation available. Champawat, Pauri Garhwal, and Tehri Garhwal districts consistently exhibited water-limited yield gaps exceeding 1.0 t ha-1 annually, highlighting irrigation sensitivity in wheat production in these areas. On the contrary, districts such as Chamoli, Dehradun, Bhageshwar, and Rudraprayag consistently maintained water-limited yield gaps below 1.0 t ha-1 each year, indicating good performance of rainfed wheat in wheat production. In the Terai region of Uttarakhand, Nainital, and Haridwar districts consistently showed higher total yield gaps compared to Udham Singh Nagar district. Nainital, Haridwar, and the Udham Singh Nagar District have 0.52 t ha-1, 0.65 t ha-1, and 0.09 t ha-1 average total yield gap respectively.