| Title: | Effects of land use/land cover and climate changes on surface runoff in a semi-humid and semi-arid transition zone in northwest China |
| Authors: | Yin, J., F. He, Y.J. Xiong and G.Y. Qiu |
| Year: | 2017 |
| Journal: | Hydrology and Earth System Sciences |
| Volume (Issue): | 21(1) |
| Pages: | 183-196 |
| Article ID: | |
| DOI: | 10.5194/hess-21-183-2017 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | climate change and land use change |
| Secondary Application Category: | hydrologic assessment |
| Watershed Description: | 45,421 km^2 Jingho River, located in central Loess Plateau region in northwest China. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | Water resources, which are considerably affected
by land use/land cover (LULC) and climate changes, are a
key limiting factor in highly vulnerable ecosystems in arid
and semi-arid regions. The impacts of LULC and climate
changes on water resources must be assessed in these areas.
However, conflicting results regarding the effects of LULC
and climate changes on runoff have been reported in relatively
large basins, such as the Jinghe River basin (JRB),
which is a typical catchment (> 45 000 km2/ located in a
semi-humid and arid transition zone on the central Loess
Plateau, northwest China. In this study, we focused on quantifying
both the combined and isolated impacts of LULC and
climate changes on surface runoff. We hypothesized that under
climatic warming and drying conditions, LULC changes,
which are primarily caused by intensive human activities
such as the Grain for Green Program, will considerably alter
runoff in the JRB. The Soil and Water Assessment Tool
(SWAT) was adopted to perform simulations. The simulated
results indicated that although runoff increased very little between
the 1970s and the 2000s due to the combined effects of
LULC and climate changes, LULC and climate changes affected
surface runoff differently in each decade, e.g., runoff
increased with increased precipitation between the 1970s and
the 1980s (precipitation contributed to 88% of the runoff increase).
Thereafter, runoff decreased and was increasingly
influenced by LULC changes, which contributed to 44% of
the runoff changes between the 1980s and 1990s and 71%
of the runoff changes between the 1990s and 2000s. Our
findings revealed that large-scale LULC under the Grain for
Green Program has had an important effect on the hydrological
cycle since the late 1990s. Additionally, the conflicting
findings regarding the effects of LULC and climate changes
on runoff in relatively large basins are likely caused by uncertainties
in hydrological simulations. |
| Language: | English |
| Keywords: | |