Effect of ecological restoration on carbon storage of damaged mountain slope in China's East Ussuri River Basin.

Ecological restoration techniques are extensively employed in the ecological restoration of damaged mountain ecosystems effectively restoring the plant community and improving soil functions. Aggregate spray seeding technology as an effective ecological restoration method, can quickly restore the damaged slopes to their previous status and keep the ecosystem functions. However, the lack of understanding of the characteristic of carbon storage as well as its influencing factors limits the scientific management of carbon sink function of the rehabilitated damaged mountain ecosystem. In this study, relying on field surveys in the East Ussuri River Basin, we analyzed the carbon storage distribution and its influencing factors in damaged mountain slopes that had been restored through the spray seeding technology after an 8-year restoration phase. The results showed that the carbon storage distribution of the damaged slopes repaired by aggregate spray seeding is in the order of soil layer > tree layer > shrub layer > litter layer > herbaceous layer. Among them, the carbon storage of the vegetation layer is mainly distributed in the tree layer, and its size is similar to that of undisturbed natural slopes. Plants and soil are the main factors affecting the carbon storage of the repaired slopes, where the plant density has a significant positive correlation with carbon storage, accounting for 19% of the carbon storage variation, and the soil bulk density has a significant negative correlation with carbon storage, accounting for 23.7% of the carbon storage variation. This study reveals the mechanism of the aggregate spray seeding technology in restoring the carbon storage of damaged slopes and points out that regulating vegetation density and improving soil conditions are key to enhancing the carbon sink capacity of slopes.