New cognition of the cultivated land quality system for the needs of multiple subjects

Arable (Cultivated) land has been highly valued for the relationship with survival and development in human history. The precious and limited natural land resource is closely related to the national food security, quality, and safety of agricultural products and ecological system. It is very necessary to fully meet the practical needs of modern agricultural development and diversified subjects of cultivated land use. Since the 18th Party Congress in Chinese government, the construction of ecological civilization has been pushed to an unprecedented height, in order to comprehensively practice the concept of "green water and green mountains are the silver mountain of gold". Among them, the quality of cultivated land can be expected to improve the ecosystem. The connotation and system composition of cultivated land quality can greatly contribute to the evaluation standards, and the quality monitoring of regional cultivated land, particularly in the more diversified needs of arable land. In this study, the quality system was established to fully meet the multiple subjects of cropland utilization and diversified demands, according to the traits and functions of cropland. The characteristics and expressions of cropland were utilized to improve the theoretical study of cropland quality. The main conclusions were as follows: 1) There were the multiple traits in the cropland for growing crops, in terms of type, space, engineering, and management, indicating the production, asset, ecological, and social functions. 2) The main subjects of cultivated land utilization were divided into the cropland management, property rights, and management subjects. The demand of cropland was divided into the production, asset, ecological and social aspects. Various subjects were divided the work around the cropland and the utilization. 3) The quality of cultivated land was corresponded to the various characteristics and functions of cultivated land, in order to meet the needs of multiple subjects using diversified cultivated land. The basic quality was divided into the land, facility, space, ecological, aesthetic, and cultural quality. 4) Cultivated land quality was a quantitative evaluation to investigate and monitor the cultivated land, according to the national standards. The following characteristics were: the integration of objective reality and subjective behavior, the combination of quality system and index system, the coupling of spatial pattern and cultivated land process, the coordination of observation scale and intrinsic scale, and the combination of variable field and type domain. 5) The quality of cultivated land was the expression for the cultivated land quality, in terms of the dimensionless quantity (absolute quantity) or dimensionless quantity (relative quantity). In general, a special relationship of supply and demand was formed between the cultivated land and the subjects of utilization, indicating the characteristics and functions of cultivated land in the needs of the subjects of utilization. The quality of cultivated land was also the long-term interaction between the subject of cultivated land use and the object of cultivated land, due to the subjective nature of cultivated land development and construction, as well as the dynamic nature of demand. The dialectical relationship between subjectivity and objectivity of arable land quality can be expected to serve as the more comprehensive understanding of cultivated land quality, in order to better improve the cultivated land quality management in China.