Tonle Sap Lake: Current status and important research directions for environmental management

Tonle Sap Lake (TSL) in Cambodia is the largest freshwater body in South‐East Asia and one of the most productive ecosystems in the world. The lake and its ecosystems are widely under threat, however, due to anthropogenic activities occurring inside and outside its basin (e.g., water infrastructure development; land use change), being poorly understood in most aspects. This study provides an updated review of the state of knowledge of the TSL ecosystem, as well as important research directions for sustainable lake environmental management of Tonle Sap Lake by focusing on four major topics, including climate change and hydrology, sediment dynamics, nutrient dynamics and primary and secondary production. The findings of this study suggest anthropogenic activities in the TSL basin, as well as the Mekong, in combination together with climate changes, are key contributing factors in the degradation of the TSL ecosystem. Insufficient accurate data, however, precludes quantitative assessment of such impacts, making it difficult to quantitatively assess and accurately understand the ecosystem process in the lake ecosystem. More efforts are recommended in regard to environmental monitoring in all sub‐basins around TSL, assessing seasonal changes in nutrient and sediment inputs corresponding to water level and flow changes, assessing cumulative impacts of water infrastructure and climate change on the ecosystem dynamics, and elucidation of ecosystem processes within the lake's internal system.