Classification of promotable green infrastructure types based on national land use planning in municipalities.

Abstract

Green Infrastructure (GI) is an idea that systematically integrates ecosystems into societal infrastructure, which could provide several ecosystem services. Recently, government support for promoting GI has been expanding, leading to increased efforts to advance GI initiatives across various regions. However, the broad and abstract nature of the GI concept poses challenges for its concrete implementation, and there is still a lack of information to guide governments in considering specific GI initiatives. When assessing the feasibility of GI implementation, it is necessary to consider both the existing ecosystems and the legal and societal constraints. This study focuses on land use planning as a factor related to the feasibility of GI implementation, particularly concerning existing ecosystems and societal constraints to propose GI types that are easy for local governments to introduce. Using the Basic Land Use Plans based on the National Land Use Planning Act, we classified 1,917 municipalities across Japan through non-hierarchical cluster analysis of land use categories by area. The results showed that municipalities could be divided into three classes when using four categories (forest, urban development areas, urban green spaces, and agricultural land) and into five classes when using three categories (excluding forests). These classes were broadly characterized as areas with active urban development, areas with substantial urban green spaces and agricultural land, and areas predominantly covered by forests and agricultural land. This classification was basically match with the areas of locational condition proposed by the guideline for Green Infrastructure, MILT. Additionally, mapping the classification results revealed a geographical clustering tendency, suggesting that cooperation among municipalities within the same class could significantly enhance GI promotion. Increasing mechanisms to support such collaboration among municipalities is expected to further contribute to the advancement of GI initiatives.