Lake ecosystem vulnerability across Southeast Asia from satellite observations

This study aims to develop a spatially scalable remote sensing framework for assessing and prioritizing lake ecosystem vulnerability across Southeast Asia. A novel Lake Ecosystem Index (LEI) is proposed by integrating a Human Pressure Index (HPI) and a Water Quality Index (WQI). The HPI was derived from land cover dynamics, including urban, agricultural, and forest changes, from 2000 to 2018, while the WQI was calculated using temporal trends of NDVI, turbidity (NDTI), and land surface temperature (LST) from 2018 to 2023. The framework was applied to 50 lakes distributed across Southeast Asia to enable comparative assessment at a regional scale. The results show that 46 % of the analyzed lakes exhibit very high vulnerability HPI scores, 16 % show very high vulnerability WQI scores, and 13 lakes fall into a high to very high vulnerability category based on combined LEI values. The proposed LEI provides a quantitative and integrative tool for identifying priority lakes requiring urgent management and restoration interventions. This study demonstrates the effectiveness of remote sensing indicators for informing policy-relevant freshwater management and advancing the monitoring of inland water ecosystems in support of UN SDG 6.6.