| Title: | Impact of Eastern redcedar encroachment on stream discharge in the North Canadian River basin |
| Authors: | Starks, P.J. and D.N. Moriasi |
| Year: | 2017 |
| Journal: | Journal of Soil and Water Conservation |
| Volume (Issue): | 72(1) |
| Pages: | 12-25 |
| Article ID: | |
| DOI: | 10.2489/jswc.72.1.12 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | land use change |
| Secondary Application Category: | hydrologic assessment |
| Watershed Description: | 1,802 km^2 North Canadian River, located in central Oklahoma, U.S. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | Eastern redcedar (Juniperus virginiana L.) is a woody plant that is rapidly encroaching
into the grasslands of states located in the US Great Plains. There is some concern that redcedar
will adversely impact stream discharge in these water-limited areas through increased transpiration
and canopy interception in comparison to that of grasslands. We conducted a modeling
study in the central reach of the North Canadian River basin between Lake Canton and Lake
Overholser, located in central Oklahoma. The North Canadian River supplies about 25% of
Oklahoma City’s water supply. After model calibration, we simulated redcedar encroachment
into the study area’s grasslands in 10% increments to assess impact on stream discharge. We also
performed simulations that represented complete removal of redcedar from the study area.
Our simulations suggested that if all grasslands in the study area were replaced by redcedar,
the simulated reduction in stream discharge would equal 112% of current municipal water
demand and 89% of the projected 2060 demand. However, a more realistic conversion of 20%
of grassland to redcedar would, according to our simulations, reduce stream discharge by an
amount of water equivalent to ≈ 27% of the current water demand, or ≈ 21% of the projected
2060 demand. Our model simulations suggest that encroachment of redcedar into grasslands
could have a detrimental effect on stream discharge, which could impact water availability on
populations further downstream. |
| Language: | English |
| Keywords: | calibration, discharge, redcedar, simulation accuracy, Soil and Water
Assessment Tool (SWAT), validation |