Ziyuan Kexue (Sep 2023)
Spatiotemporal evolution and driving factors of black soil cultivated land within the framework of critical zones on the Earth
Abstract
[Objective] Northeast black soil cultivated land (BSCL) is crucial for the country’s food and ecological security. Defining its concept and grasping the spatiotemporal dynamics is vital for sustainable resource use and regional development. [Methods] This article, based on the theory of critical zone of the Earth, redefined BSCL and combined regional soil data with land use data in 1980, 2000, and 2020. It used methods of overlay analysis and spatiotemporal analysis of land use to reveal BSCL evolution patterns and drivers over 40 years. [Results] (1) BSCL refers to cultivated land with black soil types, primarily located in the temperate zone of Northeast China, with elevation mostly below 500 m and soil predominantly composed of meadow soil. (2) Due to the impacts of climate, economic, policy and institutional factors, the area of BSCL increased by 4.12 million hm2 over 40 years. However, due to policy interventions, the increase has significantly decreased since 2000. (3) Spatially, due to the transfer of population and economic center of gravity, the overall spatial pattern of BSCL in Northeast China showed northward expansion and southward contraction. The gravity center of BSCL has been continuously moving northward, but the speed of migration has slowed down after 2000. (4) Forest and construction land were the main destinations for the transition of BSCL, while forests and grasslands are the principal sources contributing to the increase in BSCL. Influenced by policies and institutional interventions, the dynamic conversions of BSCL have undergone frequent since 2000. [Conclusion] Influenced by natural and socio-economic factors, the area of BSCL in Northeast China has significantly expanded over the past 40 years, continuously spreading northward. However, there is a obvious decreasing tendency in both the scope and speed of this expansion. This study can provide a methodological reference for the analysis of BSCL and a scientific basis for the conservation and sustainable utilization of BSCL.
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