An integrated accounting system of quantity, quality and value for assessing cultivated land resource assets: A case study in Xinjiang, China

Assessing cultivated land resource assets is a prerequisite for resource management and cultivated land protection. Existing methods on the physical quantity usually ignore the change in cultivated land quality and on the value quantity lack a unified standard framework. In this study, the calorific value was introduced to calculate the physical quantity and an integrated accounting system with quantity, quality and value was established based on the substitution market, income reduction, and equivalent factor methods. Taking 14 cities in Xinjiang as the study area, the physical and value quantities from 1990 to 2018 were calculated and analyzed to reveal the change characteristics of cultivated land resource assets. The results showed that: (1) the overall quality of cultivated land in Xinjiang improved with a fluctuating growth trend, and the cultivated land area and physical quantity increased by 58.89% and 64.54%, respectively; (2) from 1990 to 2018, a slow-to-fast increase in the total value of cultivated land was observed accompanied with a spatial distribution of "high in the northwest and low in the east". The proportion of social value grew fast, increasing from 64.02% to 83.55%, with an average annual growth rate of CNY 566.95 billion/yr; (3) during the study period, the value structure (social value: economic value: ecological value) of cultivated land resource assets in Xinjiang changed from 64.03:17.56:18.41-83.55:3.38:13.07. The social, economic, and ecological value of cultivated land per unit area increased by 11.74, 1.98, 5.94 times, respectively. The accounting system proposed in this study has the advantages of clear indicator meaning and good data availability, which is helpful to achieve cross-regional and cross-period comparison of cultivated land resource assets. These findings provide a reference for the scientific management and sustainable utilization of cultivated land resources in Xinjiang and similar oasis agricultural areas.