Water Sources, Flow Paths and Residence Time in a Forested Catchment of the East Asian Monsoon Region

TERRECO Cluster H-02

Von 10/2012 bis 09/2016

Projektleiter: Luisa Hopp
Mitarbeiter: Jean-Lionel Payeur-Poirier, Stefan Peiffer

Water yield is an important aspect of the ecosystem services provided by the Soyang Reservoir to the South Korean population. Water yield of the Soyang Reservoir is tightly linked to water discharge of the forested catchments covering 85% of the Soyang Watershed area. There is a lack of knowledge on the sources, paths and timing of water flow in these catchments during the summer monsoon. The current project aims at answering the question “When does water flow from what source, by which path, in what proportion and on what time-scale”? It is hypothesized that the high precipitation regime of the East Asian summer monsoon causes significant changes in sources, flow paths and residence time of water in forested catchments. An experimental setup used to collect hydrometric, isotopic, hydrochemical and meteorological data will be established in the summer of 2013, in a forested catchment of the Haean catchment, South Korea. The meteorological and physical conditions leading to and influencing water flow will be studied. Stable isotopes concentration as well as parameters of chemical quality will be measured from water samples in order to separate the hydrograph of the catchment into sources and flow paths components. Site, soil and forest characteristics will also be measured. The results of the project will be presented as a conceptual model of water flow paths within a forested catchment under the influence of the summer monsoon. This conceptual model will provide information relevant to the estimation of the Soyang Reservoir and Watershed water balance with the Soil and Water Assessment Tool. Furthermore, the strong linkages between water flow, quality and nutrient transport and processing and will be studied by combining the results of this project with those of other projects realised at the same location.