Keywords: BASINS, climate change, HSPF, hydrological modelling, land use change, water resources, water flow, stream flow, instream nutrient levels, watershed hydrology, surface runoff, nutrient contamination, water quality, water pollution, risk assessment
Modelling the hydrologic effects of land-use and climate changes
Climate and land use affect water quantity and quality; however, the complex relations of climate and land use regarding flow and instream nutrient levels have yet to be elucidated. This study aims to assess the hydrologic effects of different land-use and climatic regimes in the Lower Great Miami River Basin. The modelling results from BASINS showed that, as expected, agricultural lands and the wettest scenario yielded the highest amount of streamflow, fecal coliform, and nutrient loadings. But, it was the dry scenario (+2°C, -20% precipitation of the current average climatic conditions in SW Ohio), instead of the driest scenario (+4°C, -20% precipitation), that produced the highest daily nutrient concentrations. When the future land-use and climate scenarios were coupled, the worst situation was found under the current land use and the wettest condition. Hence, a change in land-use pattern may help to alleviate the adverse hydrologic impacts of climate change.