Background Soil and water resources are the key factors for agricultural production. Carrying capacity of agricultural water and soil resources (CCAWSR) is not only related to food security in regions but also affects economic development and quality of ecosystem. Relevant research may provide information for the reasonable utilization of land resources, regional sustainable development, and policy decision-making.

Methods Taking key crops production province Henan in central China as the study area, this work built up an evaluation system of CCAWSR including agricultural water, soil, society, economy and ecology, and evaluated the temporal-spatial differentiation of CCAWSR in Henan province from 2006 to 2015 by using the multi-agent genetic algorithm (MGA), the projection pursuit model (PPM), and the kernel density estimation model (KDEM).

Results 1) The main factors affecting CCAWSR in Henan province, sorted by significance in descending order, were irrigation area, proportion of investment in agro-forestry water conservancy projects, proportion of primary industry, amount of fertilizer used in farmland, area proportion of disaster-affected crops, density of population, agricultural mechanization degree, electricity consumption per unit cultivated land area, and supply and demand balance index of agricultural water resources. 2) During the study period of 2006-2015, the level of CCAWSR in Henan province decreased from -0.06 in 2006 to -0.20 in 2015, reduced by 233% in total. The CCAWSR in most cities were reduced except Zhengzhou and Jiyuan, while that in Kaifeng, Xuchang and Shangqiu decreased the most dramatically and dropped up to 585%-688%. 3) From 2006 to 2015, the spatial variation of CCAWSR in Henan province was significant. The highest value of CCAWSR was in the west and central Henan, the medium value was in the south Henan and the lowest value was in the east and north Henan. The cities with high CCAWSR reduced to 2, decreasing 50%, the cities in low CCAWSR increased to 10, increasing 2.5 times.

Conclusions The CCAWSR generally decreased, and the spatial differentiation was obviously in Henan province. In order to promote the efficient and sustainable utilization of agricultural soil and water resources, the investment of agricultural capital and ecological protection need to be strengthened and comprehensive measures such as enlarging the proportion of effective irrigated area in farmland, increasing the application of organic fertilizers should be conducted from different aspects of resources, economy, society and ecology.