Better Water and Land Allocation for Long-term Agricultural Sustainability

Water and land resources are limited and dwindling in quantity and quality due to pollution and the effects of climate change. The "world needs to produce over sixty percent more food to feed" its 9.9 billion population in 2050 using these dwindling resources. Increased food production is also necessary to achieve most of the "UN's SDGs such as SDG1 (No Poverty), SDG2 (Zero Hunger), SDG3 (Good Health and Well-Being), and SDG15 (Life on Land)", etc. The aforesaid "goal can be accomplished by optimizing the distribution of available water and land resources, which can be done through an optimization model". In this study, a water balance model was first developed "to assess the long-term groundwater recharge, which will help to understand the dynamics of the system". Then, after analyzing the results, an optimization model was formulated to maximize the net annual farm income in an irrigated region of India. The water balance model showed excellent results as indicated by "high R-squared (0.9728) and model efficiency (0.91)", and low RMSE (0.2516 m) and ME (-0.0526 m) values. The water balance analysis revealed "that the aquifer level has been rising at a steady rate" over the past two decades. The results of the water balance model were used to formulate various constraints of the optimization model. Under the optimal cropping system, the area of paddy decreases against an increase in the area of sorghum, pearl millet, and cotton during the monsoon. Whereas "during the winter, the area of wheat increases", and the area of mustard and barley decreases. Groundwater "abstraction has increased, eventually lowering the aquifer level and thus alleviating salinization and waterlogging problems in the region". Net yearly income in the region enhanced by more than twenty-two percent to ₹821.24 million from the present ₹671.33 million. The sensitivity analysis revealed that the crops' market price is the most sensitive factor in the optimization model. "It is recommended that government agencies and real-world agricultural farmers practice increased use of groundwater in conjunction with canal water to maximize farm income. The approach used is the first of its kind in the region under study, is easy to apply, and can be replicated in other regions of the world" dealing with comparative issues.