The Policy Positioning and Strategic Expectations of Landscape-Scale Green Infrastructure in Japan’s National-Level Policies

In recent years, landscape-scale green infrastructure (LGI) has evolved from academic discussions into a critical approach to achieving sustainable development in national strategies in many countries. Since 2014, Japan has proactively integrated LGI into various policy documents; however, there is still a lack of systematic research on its policy positioning and strategic expectations. This study employs text mining, qualitative comparative analysis, and policy integration analysis to establish a comprehensive analytical framework for examining 66 screened and validated national-level policy strategy documents related to LGI in Japan. The results reveal four common core themes, four potential innovative directions, and seven topics defining the policy positioning of LGI. Additionally, the study highlights thematic preferences across different departments and temporal evolution trends. The findings indicate that Japan’s policy positioning on LGI is transitioning from a technical tool to an institutionalized management framework. However, this shift remains precarious due to the influence of competing strategic priorities. The “core–periphery” departmental coordination structure exacerbates risks of policy fragmentation to some extent. Overall, while an LGI policy system has begun to take shape in Japan, further efforts are needed in cross-level linkages and collaborative governance mechanisms.