Study on formed green tracts for the function of urban heat island mitigation : reductional effect of heat island in large-scale green tracts of Tokyo

指導教員: 埼玉大学大学院理工学研究科教授 窪田陽一Recently heat island effect has become a major issue in urban areas. Green tracts are expected to play a vital role in mitigating this effect. This study aims to investigate the effectiveness of different tree species for the mitigation of heat island effect, in large-scale urban green tracts. In this study, 9 tree species in Yoyogi-park and 5 tree species in eijishrine were selected and their surface temperatures were measured by using infrared thermal images. Results show that the surface temperature level would differ based on the tree species. But such observed levels of temperature differences were not sufficient to make a significant contribution for heat island mitigation. Further, even within the same species, surface temperature varied across different locations within the same site. This difference can result from soil condition of the particular location. Thus this study shows that the soil condition of the tree base of tree growth is more influential than the tree species