Frequent geohazards exacerbate the decline of vegetation area and growth status

Geohazards pose a serious and widespread threat to regional vegetation. However, the existing studies focused on the vegetation changes under climate change and human activities, but largely ignored the impact of geohazards on vegetation. To fill this gap, time series geohazards, leaf area index (LAI), vegetation net primary productivity (NPP), and the high-precision land use/land cover data were used to explore the spatiotemporal dynamics of geohazards and vegetation in China’s Sichuan Province from 2000 to 2020. More importantly, a new conceptual framework was proposed to quantify the impact of geohazards on regional vegetation from area and growth status. The results indicate that since 2000, the number of geohazards (NGH) and the density of geohazards (DGH) showed a sharp upward trend in the study area. Another important finding was that geohazards have seriously affected the transfer direction and area of vegetation; every 1% increase in DGH will lead to a net loss of 8.76 km² area of vegetation. Moreover, geohazards hinder the growth of vegetation. Specifically, an increase of 0.01/km² in DGH caused 0.30% and 0.11% decrease in LAI and NPP in the 1000–2000 m buffer zone, whereas 0.19% and 0.08% decrease in the 2000–3000 m buffer zone. The findings contribute to a better understanding of the response mechanisms and uncertainties of vegetation to geohazards.