| Title: | Watershed discretization based on multiple factors and its application in the Chinese Loess Plateau |
| Authors: | Xu, Y.D., B.J. Fu, C.S. He and G.Y. Gao |
| Year: | 2012 |
| Journal: | Hydrology and Earth System Sciences |
| Volume (Issue): | 16 |
| Pages: | 59-68 |
| Article ID: | |
| DOI: | 10.5194/hess-16-59-2012 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | HRU, subbasin, grid and/or landscape unit delineation effects |
| Secondary Application Category: | hydrologic assessment |
| Watershed Description: | 1334 km^2 Ansai in the Loess Plateau region in north central China |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | The spatial discretization of watersheds is an indispensable
procedure for representing landscape variations
in eco-hydrological research, representing the contrast between
reality and data-supported models. When discretizing
a watershed, it is important to construct a scheme of
a moderate number of discretized factors while adequately
considering the actual eco-hydrological processes, especially
in regions with unique eco-hydrological features and intense
human activities. Because of their special lithological and
pedologic characteristics and widespread man-made vegetation,
discretization of watersheds in the Loess Plateau in
Northern China is a challenge. In order to simulate the
rainfall-runoff process, a watershed in the Loess Plateau,
referred as Ansai, was spatially discretized into new units
called land type units. These land type units were delineated
under a scheme of factors including land use, vegetation
condition, soil type and slope. Instead of using units
delineated by overlaying land use and soil maps, the land
type units were used in the Soil and Water Assessment Tool
(SWAT). Curve numbers were assigned and adjusted to simulate
runoff, using the US Natural Resources Conservation
Service (NRCS) curve number method. The results of the
runoff simulation better matched actual observations. Compared
to the results that used the original units, the coefficient
of determination (R2) and the Nash-Sutcliffe coefficient
(ENS) for monthly flow simulation increased from
0.655–0.713 and 0.271–0.550 to 0.733–0.745 and 0.649–
0.703, respectively. This method of delineating into land
type units is an easy operation and suitable approach for ecohydrological
studies in the Chinese Loess Plateau and other
similar regions. It can be further applied in soil erosion simulation
and the eco-hydrological assessment of re-vegetation. |
| Language: | English |
| Keywords: | |