Abstract

Agricultural expansion and urbanization, coupled with climate change represent major threats to the sustainability of river ecosystems and infrastructure. In this study, we evaluated how subbasins with different dominant land covers within the 27.5 km2 Clear Creek, IA watershed affect key hydrologic indicators. Hydrologic output from two stream gages and a calibrated Soil Water Assessment Tool (SWAT) model were used as input to the Indicators of Hydrologic Alteration (IHA). Study results indicated that land cover plays a dominant role in controlling hydrologic variability at the subbasin level within a watershed. Subbasins dominated by urban development had nearly 30 more reversals than row crop or grass-dominated subbasins and the duration of small and large flood events were half as long. Row crop dominated subbasins had greater water yield and maximum flows and higher peak flows, whereas grass-dominated subbasins had lower rise and fall rates, fewer zero days and fewer reversals. Hydrologic variations from land cover differences were more prominently expressed at the subbasin level than at the watershed level, as the dominant land cover represented a greater percentage of the total land area. Study results suggest that future changes in LU/LC and climate will have significant effects on the hydrology of Clear Creek Watershed.

Highlights

  • Land Use/Land Cover (LU/LC) change, including both agricultural expansion and urbanization, coupled with climate change as seen through increased fluctuations between extreme events represent two major threats to the sustainability of river ecosystems and the incorporated infrastructure (Jeong et al, 2014; Pradhanang et al, 2013; Schilling et al, 2013)

  • Study results suggest that future changes in LU/LC and climate may have significant effects on the hydrology of Clear Creek Watershed

  • Hydrologic output from a calibrated Soil Water Assessment Tool (SWAT) model was used as input to Indicators of Hydrologic Alteration (IHA) in order to evaluate the effects of land cover on streamflow in Clear Creek Watershed

Read more

Summary

Introduction

Land Use/Land Cover (LU/LC) change, including both agricultural expansion and urbanization, coupled with climate change as seen through increased fluctuations between extreme events represent two major threats to the sustainability of river ecosystems and the incorporated infrastructure (Jeong et al, 2014; Pradhanang et al, 2013; Schilling et al, 2013). In agricultural regions, increased grazing pressure and expansion of cultivation have led to soil compaction, reduced infiltration and increased runoff (Fohrer et al, 2001; Hess et al, 2010; Holman et al, 2003; McIntyre and Marshall, 2010; Moussa et al, 2002; Papanicolaou et al, 2015; Tollan, 2002) It has been well documented in the literature that farm activities like tillage and the subsequently enhanced erosion, in addition to rainfall/runoff-induced erosion, affect the composition of surface soils and their structure, such as the porous network and degree of compaction, thereby collectively affecting the spatial distribution of infiltration and saturated hydraulic conductivity within a field (Abaci and Papanicolaou, 2009; Papanicolaou et al, 2015). Urbanization affects low flows in streams as less water infiltrates into the soil and groundwater recharge is

Objectives
Methods
Results
Discussion
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.