Abstract:

Cultivated land is the basis of food production, and the quality of cultivated land affects the comprehensive production capacity of cultivated land. The central and local governments have repeatedly pointed out the need to protect the red line of cultivated land and to stabilize the policy, area and yield of grain production. The area of mountainous and hilly areas in the Xiangjiang River basin is widely distributed, and it is important to study the quality level of cultivated land in mountainous hilly areas to deepen the protection of cultivated land and improve the land productivity of cultivated land in the basin. The cultivated land in Dong'an County, a typical mountainous and hilly area in the upper reaches of the Xiangjiang River basin, was selected for quality evaluation. The results were analyzed by overlaying the soil map, current land use map and administrative division map of Dong’an County on the ArcGIS platform. The index weight was determined by hierarchical analysis, and the affiliation degree was determined by fuzzy mathematics, after the comprehensive weights were derived. The results showed that according to the evaluation standard of “quality grade of cultivated land” GB/T 33469—2016, the evaluation result was that the quality of cultivated land in Dong’an County was divided into 6 grades. Among them, the area of the third grade was 12793 hm², accounting for the highest proportion of the total area, which was 37.4%; followed by the wide distribution area of the second grade and the fourth grade, which were 8648 hm² and 6985 hm², respectively, accounting for 25.3% and 20.4%; the area of other grades of land was relatively small. The content of effective phosphorus, fast-acting potassium and organic matter of cultivated land in Dong’an County was mostly at the middle level, and the area of cultivated land with soil nutrient characteristics of Grade I, Grade II and Grade III was widely distributed, which required some targeted measures to enhance the production capacity of cultivated land.

Key words: upper reaches of the Xiangjiang River, mountainous and hilly areas, cultivated land quality, evaluation, grade