Spatiotemporal changes and the driving factors of cultivated land resources of the typical black soil region in Northeast China from 1986 to 2020

Abstract

[Objective] Cultivated land resources are the main material basis for food production. Analyzing the characteristics of the spatial and temporal changes of cultivated land resources in the typical black soil region has important reference value for optimizing the allocation of cultivated land resources. [Methods] Based on the land use data of four periods from 1986 to 2020 in the typical black soil region of Northeast China, the quantitative change of cultivated land resources characterized by the increase and decrease of cultivated land area were revealed. Taking the change of cultivated land spatial pattern as the breakthrough point, the characteristics of cultivated land resource quality change represented by site conditions were analyzed. On this basis, the driving factors of spatial and temporal changes of cultivated land resources were analyzed. [Results] (1) From 1986 to 2020, the area of cultivated land in the typical black soil region in Northeast China had been increasing, with a net increase of 2.51 × 104 km2, of which the largest increase occurred from 1986 to 2000, and the areas with more dramatic changes in cultivated land were concentrated in the southern foot of the Greater Xing’an Mountains, the Sanjiang Plain, and the areas surrounding the three provincial capital cities of the region; (2) For more than 30 years, due to the continuous movement of the center of gravity of the cultivated land to the northeast, the average temperature of the cultivated land area in the typical black soil region decreased by 0.20℃, the average humidity increased by 0.12%, and the average slope showed the change characteristics of first increasing and then decreasing; Compared with the transferred-out farmland, the temperature condition of the farmland that was transferred in was always poor, the humidity condition was generally superior, the slope condition was poor at the beginning, and better than the transferred-out farmland at a later stage; (3) In areas with low temperature (-1℃-2℃), high humidity (67%-71%), and high slope (15°-79°), cultivated land was frequently transferred in and out, with dramatic changes. [Conclusion] From 1986 to 2020, the area of cultivated land in the black soil region continued to increase, and the center of gravity continued to move northward and eastward, making the overall temperature conditions of cultivated land area worse, the humidity conditions better, and the terrain conditions basically stable. This result provides a reference for accurately judging the grain production capacity of the black soil area and scientifically utilizing and protecting the black soil.

Keywords

• |typical black soil region|cultivated land resources|site conditions|spatiotemporal change|driving factors