[M-IS21_28PO1] Biogeochemistry

[MIS21-P07] Spatial modelling of water, nitrogen and sediment for systematic conservation of multiple ecosystem services

*Min FAN¹, Hideaki SHIBATA² (1.Graduate School of Environmental Science, Hokkaido University, 2.Field Science Center for Northern Biosphere, Hokkaido University)

Keywords:Ecosystem services, SWAT, Marxan, Land use and climate change

Spatial modelling and analysis of multiple ecosystem service (ES) under land use and climate changes provides useful support for decision making in sustainable planning, management and policies of large landscapes. This study aimed to integrate the GIS modelling approach of spatial explicit ESs (water yield, and retention of nitrogen (N) and sediment) into system conservation model under various land use and climate changes in Teshio river watershed located in northern Hokkaido, Japan. In this study, we applied hydrology and material flow model (Soil and Water Assessment Tools, SWAT model), land use change model (CLUE) and system conservation model (Marxan). The multiple scenario includes three different land use maps in past (1976), current (2006) and future (2036), and three climate change scenarios (short-term (2010-2039), mid-term (2040-2069), and long-term (2070-2099) ).Our results indicated that various land use and climate change scenarios showed different impact on ES and system conservation in the watershed. The forest land use change significantly affected on magnitudes and spatial patterns in water yield, sediment and N retention. It was suggested that south western and northern part of the studied watershed should be conserved to match the given conservation targets of multiple ESs (0.3 and 0.5 of maximum ES values). The protection area to satisfy each ES conservation target increased with increase of differences between each ES and maximum ES values under land use and climate changes. Our results indicated that the land distribution and area of optimal ES protection for multiple ESs were totally different from those for single ES. The conservation area for multiple ESs was more compact than those for single ES. The proposed approach in this study provided useful information to assess the responses of ESs and system conservation under the land use and climate changes. The system conservation area of ES protection for multiple ESs provided an effective trade-off tool between environmental protection and agriculture expansion.