Improving the water and land resource system efficiency can effectively alleviate the severe situation of water and land resources in China. Through the two-stage network DEA model, spatial autocorrelation analysis, multiple linear regression, and geographic weighted regression analysis, this paper revealed the change characteristics, distribution types, spatial correlation relationship, and main driving factors of China’s water and land resources system efficiency. The results show that the water and land resources system efficiency fluctuates widely in different regions. Water and land resources systems in nearly half of the provinces belong to the high development, low economic benefit transformation type, mainly distributed in southwestern and northwestern China. The economic benefit transformation is becoming the weak link of water and land resources system. The overall efficiency of water and land resource system has significant spatial positive correlation, and this correlation has an increasing trend. Low-Low Clusters occupy more provinces. The urbanization level, population density, proportion of output value of secondary and tertiary industries, and effective irrigation all have a positive impact on the overall efficiency of water and land resources system. The impact of the proportion of construction land is bidirectional and the per land pesticide application has negative impact in general.

The comprehensive reform of agricultural water prices is an important component of China’s agricultural water conservation strategy and is highly important for ensuring national water security and sustainable agricultural development. Given the difficulty in raising water prices due to the limited carrying capacity of farmers in the reform, there is a pressing need to consider the implementation of agricultural water price sharing as a potentially viable strategy. Based on the grain production data from 2000 to 2018, the proportion of agricultural water prices borne by farmers and governments in different regions were calculated via the C-D production function method and the “Mitchell scoring + Expert scoring” method in the study. The results revealed that the average sharing coefficient of irrigation benefits for grain crops in China is 0.245. The sharing proportion of agricultural water prices for farmers in seven major geographical regions are ranked as follows: Northwest China (0.467) > Central China (0.427) > Southwest China (0.389) > Northeast China (0.358) > North China (0.319) > East China (0.312) > South China (0.163), while the sharing proportion of the government is 0.533, 0.573, 0.611 0.642, 0.681, 0.688, and 0.837. We proposed a systematic approach that directly ties cost distribution to the benefits received, and determined the proportion of agricultural water prices shared by farmers and governments, which is in line with the farmers’ economic interests and psychological demands. Furthermore, suggestions were proposed regarding the implementation of a rational agricultural water price-sharing policy.

The synergistic relation among land resources, water resources, and food production plays a crucial role in sustainable agricultural development. This research constructs a coupling coordination assessment system of the land–water–food (LWF) nexus from 2005 to 2020 for 31 provinces (municipal cities, autonomous regions) in China, and explores the current development status of land, water, and food systems at multiple scales as well as the coupling coordination characteristics of the LWF nexus. The exploring spatial data analysis and spatial Tobit model are used to explain the spatial correlations and influencing factors of coupling coordination development on the LWF nexus. On that basis, the gray GM (1,1) model is used to forecast the future development of the LWF nexus in China. The results show that the comprehensive development indexes of the land system, water system, food system, and LWF nexus are on the rise, but the land system lags behind the water system and food system. The coupling coordination degree of the LWF nexus in different regions ranges from 0.538 to 0.754, and the coupling coordination development of the LWF nexus in China has reached the preliminary coupled coordination type, with an evolutionary process similar to that of its comprehensive development level. Further empirical research shows that there is a significant positive spatial correlation between coupling coordination development levels for the LWF nexus in China. The level of urbanization and agricultural industry agglomeration have negative effects, while economic development, ecological environment, and scientific and technological progress have positive effects. The prediction results indicate that the coupling coordination degree of the LWF nexus in China will show a stable upward trend from 2024 to 2025, and most provinces will reach the intermediate coupled coordination type in 2025. This study can inform decision-making for policy-makers and practitioners and enrich the knowledge hierarchy of the LWF nexus’ sustainable development on the national and regional scales.