The combined effects of conservation policy and co-management alter the understory vegetation of urban woodlands: A case study in the Tama Hills area, Japan

Abstract

We examined the relative impacts of socioeconomic and biophysical variables on understory vegetation in urban woodlands using the example of satoyama woodland in peri-urban areas of Tokyo, Japan to determine an appropriate institutional framework for enhancing biodiversity and ecosystem services in urban woodlands. Satoyama woodland was historically managed, however, the recent abandonment endangers its biodiversity and ecosystem services. We addressed two main working questions: (1) Which variables (among conservation measures, management actors, and other environmental variables) are the main constraints on the current understory vegetation of urban woodland? (2) How does each management actor behave in the context of different conservation measures and how does this behavior affect the understory vegetation? We employed dwarf bamboo (Pleioblastus chino) as an indicator of the intensity of satoyama woodland management and combined ecological analysis with interviews of municipal officials. We found that the conditions of understory vegetation were mainly affected by differences in the behavior of management actors, as the height of dwarf bamboo was shortest at the woodland managed by community group, followed by municipality and private landowner. This suggests that it will be necessary to consider both biophysical variables and socioeconomic variables in urban ecosystem management. We also found that different management actors had different reasons to conduct or not conduct woodland management. To improve management by these multiple actors, we recommend: developing management plans for conserved areas, providing economic and non-economic support, and developing clear indicators for monitoring the effects of management, with their different behaviors in mind.