Crop conversion impacts on runoff and sediment loads in the Upper Sunflower River watershed
•Crop conversion resulted in changes in farming and irrigation practices.•Spatiotemporal changes in field management and irrigation simulated.•Irrigation practices affected the water balance during growing season months.•Potential reduction in suspended sediment loads by crop conversion in this regi...
Saved in:
| Published in: | Agricultural water management Vol. 217; pp. 399 - 412 |
|---|---|
| Main Authors: | , , , , , |
| Format: | Journal Article |
| Language: | English |
| Published: |
Elsevier B.V
20-05-2019
|
| Subjects: | |
| Online Access: | Get full text |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | •Crop conversion resulted in changes in farming and irrigation practices.•Spatiotemporal changes in field management and irrigation simulated.•Irrigation practices affected the water balance during growing season months.•Potential reduction in suspended sediment loads by crop conversion in this region.•Trend indicates continued increase in crop conversion and irrigation practices.
The Mississippi River alluvial floodplain is one of the most productive agricultural regions in the United States. In recent decades, factors of economic forces and government policies have driven crop selection and respective farming management changes in this region. This study quantified the effects of changes in crop conversion and farming management practices to discharge and sediment loads in the Upper Sunflower River watershed. Farming and climate conditions were dynamically characterized in space and time by integrating annual crop yield at the county scale, annual crop irrigation in the field scale, and an enhanced description of precipitation. This information was used as input into the Annualized Agricultural Non-Point Source (AnnAGNPS) watershed pollution model to describe existing conditions and simulate alternative scenarios. Simulations considering high irrigation adoption indicated 15% average annual percent change increase in short-term flow during the months of June, July, and August at the outlet. Conversely, simulations considering future trends in crop conversion to corn/soybean production indicates a potential reduction in average annual sediment loads for clay and silt, respectively, to 4.6 Mg/ha and 0.41 Mg/ha from 5.5 Mg/ha and 0.44 Mg/ha for existing conditions. As irrigation increases and crop production continues to shift towards corn/soybeans, these findings support the development of responsible irrigation management strategies designed for efficient water usage coupled with implementation of in field conservation practices for reduced sediment loads. |
|---|---|
| ISSN: | 0378-3774 1873-2283 |
| DOI: | 10.1016/j.agwat.2019.03.012 |