The project will increase understanding on how water in headwater streams in montane mainland Southeast Asia (MMSEA) will be affected by plausible changes in both climate and land-cover/land-use. The goals of the project are two-fold: (1) investigate the issue successfully during a field study in Thailand ; and (2) develop the capacity to conduct similar projects in three other developing countries in Asia . Using the sediment dynamics and down-stream linkage data that will be determined in the field study, the project will attempt to distinguish the degree that various types of anthropogenic change will affect erosion, sediment delivery, and water quality. The project will generate new data regarding the potential effects of climate change, which could be useful in developing sound mitigation strategies, as well as determining non-linear vulnerabilities of natural (e.g., aquatic life) and human systems (e.g., water quality decline of municipal water). The knowledge generated will be transferred to appropriate officials who make policy related to sustainability in MMSEA.