| Title: | Hydrological effects of vegetation cover degradation and environmental implications in a semiarid temperate Steppe, China |
| Authors: | Sun, L., L. Yang, L. Hao, D. Fang, K. Jin and X. Huang |
| Year: | 2017 |
| Journal: | Sustainability |
| Volume (Issue): | 9(2) |
| Pages: | |
| Article ID: | 281 |
| DOI: | 10.3390/su9020281 |
| URL (non-DOI journals): | |
| Model: | SWAT (modified) |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | land use change |
| Secondary Application Category: | snowmelt, frozen soil and/or glacier melt processes |
| Watershed Description: | 3852 km^2 Xilin River, located in the central part of the Eurasian Steppe region in northeast China. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | Studying the impact of vegetation dynamics on hydrological processes is essential for
environmental management to reduce ecological environment risk and develop sustainable water
management strategies under global warming. This case study simulated the responses of streamflow
to vegetation cover degradation under climate variations in the Xilin River Basin in a semi-arid
steppe of northern China. The snowmelt and river ice melting processes in the Soil and Water
Assessment Tool (SWAT) were improved to estimate the changes in streamflow under multiple
scenarios. Results showed that the improved SWAT simulations matched well to the measured
monthly streamflow for both calibration (determination coefficient R
2 = 0.75 and Nash–Sutcliffe
ENS = 0.67) and validation periods (R
2 = 0.74 and ENS = 0.68). Simulations of vegetation change
revealed that obvious changes occurred in streamflow through conversion between high and low
vegetation covers. The reductions in vegetation cover can elevate streamflow in both rainfall and
snowmelt season, but the effects are most pronounced during the rainfall seasons (i.e., the growing
seasons) and in drier years. These findings highlight the importance of vegetation degradation on
modifying the hydrological partitioning in a semi-arid steppe basin. We conclude that in a particular
climate zone, vegetation cover change is one of the important contributing factors to streamflow
variations. Increases in streamflow in water-limited regions will likely reduce the effective water
content of soil, which in turn leads to further degradation risk in vegetation. Therefore, vegetation
cover management is one of the most effective and sustainable methods of improving water resources
in water-constrained regions. |
| Language: | English |
| Keywords: | vegetation cover degradation; improved SWAT model; streamflow; overgrazing; semi-arid region; climate warming; Xilin River Basin |