Driving forces of NPP change in debris flow prone area: A case study of a typical region in SW China

Abstract Net primary productivity (NPP) is one of the essential indicators of regional eco-environment security. In ecologically fragile areas, debris flow prone areas are extremely sensitive to human and natural impacts. In this study, our goal was to explore the main driving forces and their characteristics that caused changes in NPP. This was achieved by collecting and analyzing multi-source data of a typical region in SW China. A pixel-based spatial analysis method was conducted in this study to quantify the co-evolution characteristics between NPP and the main driving forces. Our results showed that the overall NPP in the region exhibits an increasing trend. The main driving forces are NDVI and population density, which can explain >70% of the environmental states. In addition, co-evolution characteristics were obvious; generally, NDVI had a positive effect and population density had a negative effect. However, extremely significant negative correlations between NPP and NDVI were found in 12.01% of the study area. Therefore, carrying out reasonable ecological restoration and applicable human activities in debris flow prone areas could ensure eco-environment security and sustainable development. This study contributes to improving our understanding of eco-environment evolution of critical zones and provides a scientific basis for regional eco-environment security construction and eco-treatment of debris flow.