Environmental degradation in the transnational area of Changbai Mountain based on multiple remote sensing data

Rapid and effective assessment of environmental degradation is essential for promoting regional sustainable development in the transnational area of Changbai Mountain (TACM). However, a comprehensive understanding of environmental degradation in the TACM remains inadequate. In this study, we developed an environmental degradation index (EDI) using multiple remote sensing data, including the enhanced vegetation index, gross primary productivity, land surface temperature, and moderate resolution imaging spectroradiometer (MODIS) surface reflectance products. We then evaluated the performance of the developed index in comparison with that of the remote sensing ecological index and assessed environmental degradation across the entire TACM, in the subregions of China, the Democratic People's Republic of Korea (DPRK), and Russia from 2000 to 2019. The results indicate that the EDI has various advantages, such as speed, flexibility, and simplicity, and can be used to effectively identify and evaluate the environmental degradation dynamics caused by urban expansion and cropland loss. The TACM experienced a downward trend in environmental change from 2000 to 2019. Degraded environment areas (49,329.50 km²) accounted for 30.09% of the entire TACM. The largest area of the degraded environment was in the DPRK subregion (i.e., 25,395.00 km²), which was 5.6‐times and 1.3‐times larger than that in the Russian and Chinese subregions, respectively. Hotspot areas that experienced significant environmental degradation covered only 17.69% of the land area of the TACM, within which the area of environmental degradation accounted for 33.89% of the total degraded environment across the entire TACM. We suggest that international cooperation policies and measures be enacted to promote sustainable regional development.