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.