Identifying ecological compensation areas for ecosystem services degradation on the Qinghai-Tibet Plateau

Ecological restoration is the most promising way to combat ecological degradation and improve ecological stability. However, it remains unclear at what scale ecological restoration is needed for the ecological degradation region related with ecosystem services under ongoing and future climate change. Based on that, this study assessed carbon sequestration (CS), water supply index (WSI), and mean species abundance (MSA) from 2000 to 2020 on the Qinghai-Tibet Plateau (QTP). Moreover, utilizing the Offset Portfolio Analyzer and Locator model to map and quantify the impacts of ecological degradation on CS, WSI, and MSA. Furthermore, this study explored the compensation area based on protection and restoration two compensation types under the shared socioeconomic pathway (SSP) and representative concentration pathway (RCP) scenarios between 2030 and 2060. The results showed that the spatial distribution of CS and WSI had a generally gradual declining trend, and MSA had an increasing trend from the southeast to the northwest. Ecological degradation of 1.21 x 10(6) ha has impacted 1.39 x 10(6) ha of terrestrial ecosystems on the QTP, and at least 7.47 x 10(6) ha of compensation area is needed. Regarding the protection scenario, the compensation area is mainly located in the western and northeastern parts of the QTP, with the highest CS of 8.05 x 10(5) Mg ha(-1) in the SSP1-RCP1.9 scenario and the highest WSI of 0.09 in the SSP4-RCP6.0 scenario. Regarding the restoration scenarios, SSP2-RCP4.5 showed a strong CS capacity with a value of 3.30 x 10(5) Mg ha(-1), while the SSP4-RCP6.0 scenario had an adequate water supply capacity with a WSI value of 0.61. Our findings indicate that a multifaceted assessment can determine the extent of ecological restoration required to mitigate different scales of degradation. This will help conservation managers develop more targeted sustainable management policies.