Study on Water Resource Carrying Capacity and Crop Structure Optimization Based on Gray Relational Analysis

This study addresses challenges such as insufficient irrigation water quotas, severe groundwater over-extraction, and conflicts around crop water usage within the mixed-cropping areas of the Inner Mongolia Yellow River Basin. Five evaluation factors-water resource utilization efficiency, irrigation rate, degree of development and utilization, supply modulus, and demand modulus-were selected for a gray relational analysis to assess the 2023 water resource carrying capacity. A crop structure optimization model was developed using machine learning, focusing on minimizing water use while maximizing economic benefits. The results indicate that groundwater resources are nearing critical levels, with many regions showing low carrying capacities and supply-demand conflicts. Key issues include unreasonable planting structures and excessive irrigation quotas, leading to significant water waste. To optimize resource utilization, it is recommended to reduce the food crop planting area by 0.0194 × 10⁴ hm² and increase economic and forage crops by 0.0106 × 10⁴ hm² and 0.0116 × 10⁴ hm², respectively. This adjustment would lead to a total water utilization reduction of 0.0289 × 10⁶ m³ per year, an increase in total yield of 4340.86 tons, and an increase in total economic benefit of CNY 6,559,200, thus leading the cropping structure towards greater rationality. The findings provide valuable insights for optimal water resource allocation in mixed-cropping irrigation areas.