Changes in and driving forces of ecosystem services in tropical southwestern China

Tropical forests provide important ecosystem services and biodiversity for the world. With human activities and economic growth, tropical forests are becoming the primary sources of new plantations, making tropical regions hotspots of ecosystem service degenerations and biodiversity losses. Understanding the driving forces of ecological consequences is the key to local sustainable development and human well-being improvements. Therefore, we spatially quantified the changes in ecosystem services in tropical China in the past twenty years by remote sensing and InVEST model. The driving forces were further investigated by using Geodetector. We found that: 1) in the past twenty years, the area of evergreen broad-leaved forests, coniferous forests, and rubber forests have increased by 13.01%, 43.39%, and 101.23%, respectively. The shrublands and agricultural lands are the major contributors to these increased areas; 2) with the area increasing of forests, carbon storage and soil retention have increased by 9.40% and 0.30%, while nitrogen export and water yield have decreased by 43.30%, and 12.27%. This pattern of increase in carbon storage and soil retention was found in the highlands, while not in the lowlands, where large areas of evergreen broad-leaved forests have been converted to rubber forests; 3) NDVI was highly correlated to the carbon storage (q value = 0.201) and nitrogen export (q value = 0.109), while slope and precipitation mainly affected the soil retention (q value = 0.253) and water yield (q value = 0.073), respectively. This study provides a reference for ecological protection and management in tropical China.