2.3 Data preparation

The DEM data for the hydrologic analysis can be obtained from the UnitedStates Geological Survey HYDRO1K (website： http： //edcdaac.usgs.gov/gtopo30/hydro/) in the resolution of a 1km×1km grid.DEM and the hydrological analysis module，includes sink filling，flow direction generation，rivernetwork extraction，and the river network simulation were determined basedon DEM.

The land use data of China can be obtained from the National County LandCoverage Vector Data，the product of the research，“Macro-scale Surveyand Dynamic Study of Natural Resources and Environment of China by Remote Sensing，” conducted by the Chinese Academy of Sciences (CAS).Forglobal land cover data，the USGS have provided a 1km resolution global landcover characteristics data for environmental research an ......     （共1635字）    [阅读本文]>>