Poyang Lake is a dynamic wetland system where water depths are deep during the summer rainy season and shallow during the winter dry season. How deep or how shallow water becomes varies greatly each year. Poyang Lake is also one of the largest wetlands in Asia with an area of approximately 4,000 km 2 (Shankman 2006). In addition to the five main tributaries that drain into the lake, Poyang also has a seasonal, reverse-flow system which greatly contributes to the complexity of its yearly hydrological variation. This variation, both within and among years, directly contributes to the large biomass of plant life (Li et al. 2004), which provides a wide range of foraging options for many waterbird species (Cao et al. 2008). Siberian Cranes, which depend solely on the lake for wintering habitat, are one example. As a key winter area for waterbirds, an analysis of how various impacts from development can alter this ecosystem is critical because mismanagement of this ecosystem can lead to extirpation of species, such as Siberian Cranes, from the wild.

This report evaluates the estimated impact of artificially raising minimum winter water levels, and reducing the seasonal and annual variability of water levels at Poyang Lake by building a dam at the outlet of the lake. To fully assess the impact of a development project such as a dam, water level is not the only important characteristic to measure at Poyang Lake. The timing of when, and the location of where, water occurs in the ecosystem is also important. So is quality