赣江中上游地区土地利用变化空间分异与驱动因素

赣江中上游地区是东南丘陵重要的水土保持功能区,分析不同时空尺度下该区域土地利用变化及其驱动力,对维持与优化本地生态功能具有重要意义。本研究基于1 km空间分辨率的土地利用数据,分析1980—2018年赣江中上游地区的土地利用结构与土地利用动态度;并利用主成分分析法(PCA)、普通最小二乘法(OLS)和地理加权回归(GWR)分析土地利用变化的空间分异驱动力。结果表明: 1980—2018年,研究区主要土地利用类型是林地(面积占比69.4%～71%)和耕地(占比20.8%～20.9%);建设用地、未利用地的土地利用动态度较大,研究区综合土地利用动态度逐渐增加,尤其是2010—2018年明显增加。GWR模型对研究区土地利用变化驱动因素分析的拟合效果更好,在98.6%的区域内都比较理想。在土地利用变化空间分异的影响因素中,自然环境因素对研究区土地利用变化空间分异的影响最明显,起制约作用;社会经济因素的影响居次位,主要起促进作用;自然-社会因素综合影响较弱且复杂。

Spatial heterogeneity and driving factors of land use change in the middle and upper reaches of Ganjiang River,southern China

The middle and upper reaches of Ganjiang River is an important functional area for soil and water conservation in the southeastern hills of China. It is important to analyze the land use change and their driving forces at different spatial and temporal scales to maintain and optimize the local ecological functions. We analyzed the land use structure and land use dynamics in the middle and upper reaches of Ganjiang River from 1980—2018 based on 1 km spatial resolution land use data, and analyzed the spatial heterogeneity and driving factors of land use change using principal component analysis (PCA), ordinary least squares (OLS) and geographically weighted regression (GWR). From 1980-2018, the main land use types in the study area were forests (proportion 69.4%-71%) and cultivated land (proportion 20.8%-20.9%). Land use dynamic degree of build-up land and unused land were larger, and the comprehensive land use dynamic degree gradually increased, especially in 2010-2018. The GWR model had a better fitting effect on the analysis of land use change drivers, which was better in 98.6% of the area. Among the influencing factors of the spatial heterogeneity of land use change in the study area, the natural environment factors were the most obvious, with a restrictive role. The socio-economic factors were the secondary in importance, with a promoting role. The comprehensive influence of natural and social factors were weak and complex.