Ecohydrologic modelling of water resources and land use for watershed conservation

• Land use land cover can affect hydrologic processes directly or indirectly.
• Watershed-based approach is needed for long term landscape planning.
• An integrated approach links hydrologic risk and suitability analysis.
• Ecohydrologic prioritization using spatial analysis
• Ecohydrologic evaluation of landscape decisions

Land use land cover is an important determinant of ecohydrologic processes in watershed systems. Continued urbanization changes the very nature of ecohydrological regimes of watersheds and increases their vulnerability to flooding, soil loss, and water pollution. To integrate hydrologic risk and suitability analysis into land use decisions, we used an ecohydrologic risk criteria for land use impacts on water quality and quantity in the Riva Creek watershed located to the east of Istanbul, Turkey. Hydrological risks are modeled for each sub-watershed using a spatial analysis. A spatial quantitative assessment is used to rank sub-factors for evaluating suitability for agricultural, residential and forest operations. An expert focus group is used to quantify weights. The results revealed that about 58% of the watershed is prone to hydrologic risk in medium to severe levels. We concluded that ecohydrological evaluations should form the background of landscape assessments in watersheds. An integrated approach and spatial results can provide the basis for long-term planning.