Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 18 Advances and visions in large-scale hydrological modelling 2008 10.5194/adgeo-18-3-2008 http://www.adv-geosci.net/18/3/2008/ http://www.adv-geosci.net/18/3/2008/adgeo-18-3-2008.html http://www.adv-geosci.net/18/3/2008/adgeo-18-3-2008.pdf 3 8 2008-06-20 Gauging the ungauged basin: a top-down approach in a large semiarid watershed in China F. K. Barthold frauke.barthold@umwelt.uni-giessen.de T. Sayama K. Schneider L. Breuer K. B. Vaché H.-G. Frede J. J. McDonnell Institute for Landscape Ecology and Resources Management, Justus-Liebig-University Giessen, Germany Department of Forest Engineering, Oregon State University, Corvallis, USA A major research challenge in ungauged basins is to quickly assess the dominant hydrological processes of watersheds. In this paper we present a top-down approach from first field reconnaissance to perceptual model development, model conceptualization, evaluation, rejection and eventually, to a more substantial field campaign to build upon the initial modeling. This approach led us from an initial state where very little was known about catchment behavior towards a more complete view of catchment hydrological processes, including the preliminary identification of water sources and an assessment of the effectiveness of our sampling design. Chen, Z.: Topography and climate of the Xilin river basin (in Chinese with English abstract), Inner Mongolia Ecosystem Grassland Station, Research on Grassland Ecosystems, 3, 13–22, Beijing, Science Press. 1988. Christopherson, N. and Hooper, R. P.: Multivariate analysis of stream water chemical data: The use of principal components analysis for the end-member mixing problem, Water Resour. Res., 28, 99–107, 1992. Elsenbeer, H. and Lorieri, D.: Mixing model approaches to estimate storm flow sources in an overland flow-dominated tropical rain forest catchment, Water Resour. Res., 31(9), 2267–2278, 1995. Grayson, R. B., Gippel, C. J., Finlayson, B. L., and Hart, B. T.: Catchment-wide impacts on water quality: the use of `snapshot' sampling during stable flow, J. Hydrol., 199, 121–134, 1997. Hill, A. R.: Base cation chemistry of storm runoff in a forested headwater wetland, Water Resour. Res., 29(8), 2663–2675, 1993. Ketzer, B., Bernhofer, C., and Liu, H.: Surface characteristics of grasslands in Inner Mongolia as detected by micrometeorological measurements. Int. J. Biometeorol, in press, doi:10.1007/s00484-008-0145-5b, 2008. Klemeš, V.: Conceptualization and scale in hydrology, J. Hydrol., 65, 1–23, 1983. Neal, C., Wilkinson, J. Neal, M., Harrow, M., Wickham, H., Hill, L., and Morfitt, C.: The hydrochemistry of the headwaters of the River Severn, Plynlimon, Hydrol. Earth Syst. Sci., 3, 687–696, 1997. Schneider, K., Ketzer, B., Breuer, L., Vaché, K. B., Bernhofer, C., and Frede, H.-G.: Evaluation of evapotranspiration methods for model validation in a semi-arid watershed in northern China, Adv. Geosci., 11, 37–42, 2007. Seibert, J. and McDonnell, J.J.: On the dialog between experimentalists and modeler in catchment hydrology: Use of soft data for multicriteria model calibration, Water Resour. Res., 38(11), 1241, doi:10.1029/2001WR000978, 2002. Sivapalan, M.: Predictions in ungauged basins: a grand challenge in theoretical hydrology, Hydrol. Process., 17, 3163–3170, 2003. Sugawara, M.: On the analysis of runoff structure about several Japanese rivers, Jap. J. Geophys., 2(4), 1–76, 1961. Sugawara, M.: Tank Model, in: Computer Models of Watershed Hydrology, edited by: Singh, V. P., 1995. Tong, C., Wu, J., Yong, S, Yang, J., and Yong, W.: A landscape-scale assessment of steppe degradation in the Xilin River Basin, Inner Mongolia, China, J. Arid Environ., 59, 133–149, 2004.