| Title: | Pronounced increases in Future soil erosion and sediment deposition as influenced by freeze−thaw cycles in the Upper Mississippi River Basin |
| Authors: | Wang, Q., J. Qi, H. Qiu, J. Li, J. Cole, S. Waldhoff and X. Zhang |
| Year: | 2021 |
| Journal: | Environmental Science & Technology |
| Volume (Issue): | 55(14) |
| Pages: | 9905–9915 |
| Article ID: | |
| DOI: | 10.1021/acs.est.1c02692 |
| URL (non-DOI journals): | |
| Model: | SWAT-FT & SWAT |
| Broad Application Category: | pollutant only |
| Primary Application Category: | snowmelt, frozen soil and/or glacier melt processes |
| Secondary Application Category: | sediment loss and transport |
| Watershed Description: | 492 000 km^2 Upper Mississippi River Basin, located in the north central region of the U.S. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | Soil erosion and sediment deposition are relevant to multiple important ecosystem services essential for natural and
human systems. The present study aims to project future soil erosion and sediment deposition in the Upper Mississippi River Basin
(UMRB) using climate projections by five Global Circulation Models (GCMs) under the Representative Concentrations Pathway
(RCP) 8.5 scenario. To understand the importance of freeze−thaw cycles (FTCs) for soil erosion and sediment deposition
estimation with climate change, this study compared two Soil and Water Assessment Tool (SWAT) models with different
representations of the FTCs, with the standard SWAT using a simple regression method and SWAT-FT employing a physically
based method. Modeling results show that future climate change can pronouncedly intensify soil erosion and increase sediment
deposition, and the impacts are sensitive to how FTCs are represented in the model. The standard SWAT projected an increase in
soil erosion by nearly 40% by the end of the 21st century, which is much lower than the projected over 65% increase in soil erosion
by SWAT-FT. For sediment deposition, the projected percent changes by the standard SWAT and SWAT-FT also deviate from each
other (i.e., about 70% by the standard SWAT vs about 120% by SWAT-FT). Overall, these results demonstrate the important roles
of FTCs in projecting future soil erosion and sediment deposition and underline the need to consider the effects of conservation
practices on FTCs to realistically assess the effectiveness of those measures. |
| Language: | English |
| Keywords: | |