A study on the characteristics of green infrastructure in Tama-Miura hilly region and perspectives on Metropolitan Tokyo Regional Planning based on the watershed analysis

The purpose of this paper is to clarify the characteristics of green infrastructure in Tama-Miura hilly region, located in Metropolitan Tokyo, and consider perspectives of Water Circulation Planning based on the watershed analysis. The following three points have clarified. The first is there exist 79 watersheds, and six types of watersheds have analyzed by introducing Natural Land Use Units, which has created by the combination between geography and potential vegetation map. The second is the capacity of permeability of rain-fall has calculated and it differs a lot, depend on the characteristics of six types. Therefore, it becomes possible to develop strategies for recovering healthy water circulation, considering the function of water circulation system of each watershed. The third is Water Circulation GI Core Area and Corridor have identified, as the structure of Metropolitan water circulation planning. In Tokyo Metropolitan Region, there existed the recreational planning since 1939, the planning of greenbelt in the 1950’s and natural preservation planning since the 1970’s. By introducing Natural Land Use Units and estimating the possibility of water storage, it becomes possible to develop the precise water circulation planning for achieving the resilient region for flooding problems which have been accelerated by climate changes.