Simulation of ecosystem service responses to multiple disturbances from an earthquake and several typhoons

Abstract

Ongoing environmental disturbances (e.g., climate variation and anthropogenic activities) alter an ecosystem gradually over time. Sudden large disturbances (e.g., typhoons and earthquakes) can have a significant and immediate impact on landscapes and ecosystem services. This study explored how precipitation variation (PV) and land use/land cover (LULC) changes caused by multiple disturbances can cumulatively impact ecosystem functioning in the Chenyulan watershed in central Taiwan. We simulated four ecosystem services (water yield production, water purification, soil conservation, carbon storage) and biodiversity using the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model to analyze the spatiotemporal changes and obtain information regarding changes in the ecosystem. Our results indicate that the Chi-Chi earthquake had the greatest impact on the ecosystem. Specifically, the ecosystem was altered by the earthquake and could no longer absorb disturbances of a similar magnitude as before the earthquake. By differentiating the impacts of the PV and LULC changes on ecosystem services and biodiversity, we observe that the PV had a stronger impact on water yield and soil conservation, whereas the LULC change had a stronger impact on water purification. Our results also suggest that a comprehensive ecosystem management plan should consider the cumulative and hierarchical context of disturbance regimes to prevent reductions in ecological variability and ecosystem resilience, particularly in areas that are more sensitive to large disturbances. In this way, ecosystem resilience may be maintained at a level sufficient to preserve ecosystem functioning and ecosystem services in the event of unexpected large-scale environmental disturbances.