| Title: | Estimation of sediment yield change in a Loess Plateau basin, China |
| Authors: | Zhang, L., R. Karthikeyan, H. Zhang and Y. Tang |
| Year: | 2017 |
| Journal: | Water |
| Volume (Issue): | 9(9) |
| Pages: | |
| Article ID: | 693 |
| DOI: | 10.3390/w9090683 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic and pollutant |
| Primary Application Category: | critical source area assessment |
| Secondary Application Category: | sediment loss and transport |
| Watershed Description: | 3,430 km^2 Upper Sang-Kan River, located in the Loess Plateau region in northern Shanxi Province in northeast China. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | Soil erosion is one of the most serious land degradation problems and the primary
environmental issue in the Loess Plateau region of China. To identify the critical sub-basins and
assess the impacts of land use change and climatic variability change on soil loss, this study tested the
feasibility of the Soil and Water Assessment Tool (SWAT) model on sediment load simulation in the
upper Sang-kan (USK) River basin. Based on a land use map of 1986, the SWAT model (Scenario 0) was
calibrated at a monthly step using climate data from 1979 to 1985; then it was validated using climate
data from 1986 to 1990. The monthly sediment simulation results indicated that the model did not
work as well as streamflow simulation, indicating lower NS (Nash-Sutcliffe Efficiency) and r2 values
of 0.68, 0.69 and 0.61, 0.59 for the calibration period and validation period, respectively. This model
could perform well under relatively low rainfall events, but it underestimated or overestimated the
sediment load under high rainfall events. Comparing the results of scenarios with different land use
maps (year of 1986 vs. 2012) and climate periods (1979–1990 vs. 2001–2012), it can be concluded that:
(i) extreme and severe erosion almost always happened in FRST (forest land) and RNGE (grassland)
in the hilly area; (ii) long-term traditional farming weakens the soil anti-erosion capability of land,
leading to higher soil erosion, while forest can improve the soil structure, enhance the soil anti-erosion
capability, and reduce soil erosion; (iii) both land use change and climatic change have led to the
sediment yield decrease in the USK basin. Acting as the major influencing factor, land use change
contributed to about 64.9% of the sediment yield reduction in the USK river basin. |
| Language: | English |
| Keywords: | streamflow; sediment yield; simulation; ArcSWAT |