| Title: | Modeling the Dynamics of carbon dioxide emission and ecosystem exchange using a modified SWAT hydrologic model in cold wetlands |
| Authors: | Melaku, N.G., J. Wang and T.W. Meshesha |
| Year: | 2022 |
| Journal: | Water |
| Volume (Issue): | 14(9) |
| Pages: | |
| Article ID: | 1458 |
| DOI: | 10.3390/w14091458 |
| URL (non-DOI journals): | |
| Model: | SWAT (modified) |
| Broad Application Category: | hydrologic and pollutant |
| Primary Application Category: | GHG and/or ammonia emissions |
| Secondary Application Category: | wetland effects and/or processes |
| Watershed Description: | 160,935 km^2 Athabasca River, which drains to Lake Athabasca in northeast Alberta, Canada. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | The restoration and protection of wetlands are crucial in reducing greenhouse gas emissions.
In this research, the SWAT model was modified to investigate and estimate the groundwater
table, net ecosystem exchange (NEE), and soil respiration impact on carbon dioxide (CO2) emission
in the cold regions in Alberta. There is a lack of a process-based model that accounts explicitly for
the CO2 emission and ecosystem exchange resulting from interactions between hydrological and
biogeochemical processes. The SWAT model is modified to make unique contributions to wetlands
by estimating CO2 emissions, soil temperature, and soil respiration that account for the dynamics of
water tables and the relationship between subsurface and surface water storage. The modified
model results predicted daily NEE with a very good model fit resulting in an R2 (Coefficient of
determination), NSE (Nash-Sutcliffe Efficiency), PBIAS (percent bias), and RMSE (root mean square
error) of 0.88, 0.72, 2.5, and 0.45 in the calibration period and 0.82, 0.67, −1.8, and 0.56 for the validation
period, respectively. The prediction result indicated that the modified model performed well
in predicting soil temperature, the groundwater table, and ecosystem respiration in the calibration
and validation periods. In general, this study concluded that the modified model has the capability
of representing the effects of water table dynamics on CO2 emissions and NEE in cold wetlands. |
| Language: | English |
| Keywords: | modified SWAT; CO2; soil respiration; groundwater table |