Net primary productivity changes associated with landslides induced by the 2008 Wenchuan Earthquake

Abstract

Abstract The 2008 Wenchuan Earthquake triggered massive landslide erosion, especially in mountainous terrain, which had a great impact on carbon storage of the local terrestrial ecosystem. However, variation in carbon flux and restoration of ecosystem function after the Wenchuan Earthquake remain open issues. In this study, we evaluated the current restored vegetation productive capability on the coseismic landslide scars through moderate resolution imaging spectroradiometer (MODIS) net primary productivity (NPP) imagery, and explored their sensitivity to meteorological, topographical, and geological factors. The spatio‐temporal evolution and future sustainability of NPP of the landslides after the Earthquake were revealed. The following results were obtained: (i) After 13 years, only 45.36% of the vegetation productivity capability of the landslide scars reached the pre‐earthquake level. (ii) Meteorological factors (precipitation and temperature) have strongest influences on vegetation productivity capability recovery over the coseismic landslide scars, followed by topography (aspect, slope, and altitude) and the lithology of landslides. (iii) The extremely significant improvement ( p < 0.01) and significant improvement (0.01 ≤ p < 0.05) in annual NPP pixel values from 2008 to 2021 accounted for 18.92% and 28.30% of the total area, respectively. The slight degradation ( p < 0.1) in annual NPP pixel values from 2008 to 2021 account for 0.01% of the total area. In general, the NPP has shown an improving trend since the Wenchuan Earthquake. Moreover, 60.95% of the total area shows the trends of continuous improvement in the future. This study provides important insight into how mega‐earthquakes affect regional ecosystem carbon flux and contributes to our understanding of ecosystem carbon cycles along with earthquake‐induced geohazard chains.

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