Spatiotemporal dynamics and ecological impact of photovoltaic power plants in China (2000 <i>–</i> 2023): a remote sensing approach

The global proliferation of photovoltaic power plants (PV) has greatly contributed to alleviating the energy crisis and addressing global warming caused by carbon emissions. Accurately assessing the ecological impacts of PV power plants is crucial for balancing ecological protection and the sustainable development of the PV industry. This study used the Google Earth Engine (GEE) platform to construct an object-oriented random forest model, obtaining annual spatial distribution data for PV in China from 2000 to 2023, and quantifying the ecological effects of PV installations at the regional level. The results revealed a phased expansion of PV power plants since 2000, including a germination phase, start-up phase, expansion phase, and boom phase. As of 2023, the total PV area in China was 7716.13 km2, with the northwest region having the largest installed PV capacity, accounting for 35.76% of the total PV area in China. Most PV installations were located in grassland, cropland, and barren land, which together accounted for more than 85% of the total. Compared to cropland, where about half of the samples improved, PV installations on barren land and grassland showed around 90% and 85% improvement respectively, with smaller NDVI declines and stronger recovery. Furthermore, large-scale PV construction enhanced ecological functions such as shading, cooling, wind-proofing, and sand fixation, thus contributing more effectively to promoting local vegetation growth. This study provides data support and a scientific basis for optimizing the distribution of PV power plants and promoting the development of “PV+” compound projects.