Impacts of Landscape Pattern on Water Flow Regulation Service of Forest Ecosystems

Landscape patterns are being changed by humans on an ever-growing scale. The changes for land use preference potentially influence ecosystems and ecologic cycles including water. Yet, forest ecosystems provide a large number of benefits to humans, including water flow regulation. Vegetation is a major factor in forest ecosystems to regulate water production and water quality protection. These positive impacts can decrease when forests are fragmented. A relationship exists between water flow regulation service and landscape patterns, and this regulation service can be quantified for different types of ecosystems. In this study, we assessed water flow regulation services from forest ecosystems at sub-watershed level in semi urban landscapes using landscape patterns. We quantified water flow regulation by determining flow coefficients for all land uses, including forests. To determine relationships between water flow regulation and landscape patterns we used metrics (PLAND, LPI, ENN_MN, and AI). Results show that landscape structure impacts water flow regulation. Hydrologic responses and their implications to water resources vary among different land uses. Determining flow coefficients in forest areas has shown a negative correlation between water yield and PLAND and LPI. Results also show a positive correlation between water yield and ENN_MN and AI due to forest fragmentation. Key Words: Water flow regulation, forest ecosystem services, landscape planning, landscape patterns. This study was supported by TUBITAK (The Scientific and Technological Research Council of Turkey) with project number of 112Y096 and Istanbul University with project number of 35512.