Land Use Evolution and Its Driving Factors over the Past 30 Years in Luochuan County

Understanding the evolution of land use change and its drivers is vital in keeping the fragile balance between human activities and nature. The present study employs remote sensing data from between 1990 and 2020 during the Grain-for-Green Project (GGP) in Luochuan county, Shaanxi Province, which offers 30 years of continuous data on precipitation, temperature, population, and GDP. Here, the combined method of supervised classification with manual visual interpretation was adopted for building a high-precision spatial distribution information database, in order to explore the links existing between the change features of land use, distribution, and spatial pattern, and the interference of local socio-economic development and natural factors before and after the GGP. According to the results, during the past three decades, Luochuan county has undergone large changes in land use types, displaying distinct features and regional disparities. Geographically, the north of Luochuan county is predominantly forest and grassland, while farmland is mostly in the south of Luochuan county. In 1990, farmland dominated this county; however, after 2000, forest and grassland areas expanded. Notably, the implementation of the GGP significantly influenced changes in grassland and forest areas. With the development of modernization, Luochuan county's land use structure has gradually equilibrated, with increased uniformity in the distribution of various land use types. Obviously, the shift in land use from 1990 to 2020 primarily correlates with mean annual temperature, annual precipitation, total population, and GDP. Furthermore, regression analysis revealed that during the initial decade of the GGP, natural factors primarily drove land use changes. However, after the GGP, the conversion rate from farmland to forest and shrubland/grassland escalated, and population growth was the continual external force driving the expansion of forest and grassland. Despite substantial economic benefits from land development and utilization in Luochuan county during the past 30 years, certain human economic activities have posed significant pressure on regional agricultural development and sustainable land resource use. Overall, this study helps our government to enhance national land management and planning through a targeted method, also providing a reference for analyzing land use change processes within same areas.