Misc

This study aimed to understand the quality of the green space in the reclaimed land of Tokyo bay area from the aspect of organisms. The method to sort the green space environment of reclaimed land on the artificial ground with ecological function has not been examined. In this research, we selected Orthoptera (grasshopper, katydid and grig) as an index organism because it is closely related to the structure of green space and expected to inhabit on artificially made land. Therefore, the biotope type of the seaside area was examined with the relation to the habitat of Orthoptera and to the environmental information of green coverage. In this investigation, we recorded the number of individuals and the species of Orthoptera at 72 sites such as the parks, greenbelts, and planted zones. The relationship between environmental information of green coverage and habitat information of Orthoptera was analyzed based on the green classified chart. We classified groups of Orthoptera by TWINSPAN and analyzed the relationships of individual number of Orthoptera groups with environmental factors, using GLMM. In the result, Orthoptera groups receives the influence about distribution of green coverage in the near area and the distance from existing habitat.

There is a huge number of small irrigation ponds in the agricultural landscape of the north of Awaji Island, Hyogo Prefecture. Recently, managements of many ponds have been abandoned. However, these ponds are used as habitat by many organisms. They have an important role to maintain biodiversity in this area. Dragonfly (Odonata) species were surveyed in 24 irrigation ponds in Hokudan-cho, the north of Awaji Island. Thirty-seven species were caught and/or observed from June to September 2000. The number of dragonfly species had no relation with water body area of irrigation ponds. Twenty-four ponds were classified to five types by TWINSPAN (Two-way Indicator Species Analysis). The classification of TWINSPAN was analyzed by Classification and Regression Trees using explanatory variables about environmental factors of irrigationponds. The results showed that altitude, neighboring woodlots, water body area and water quality influenced the component of dragonfly species. Especially, it was important for species preferring edge and/or inside of woodlot that over 45 percents of pond surroundings were adjacent to woodlots. It was also suggested that surrounding land uses influenced the distribution of dragonfly species.

I investigated birds from 15 January to 24 February 2004 along 8 wooded streets in central area of Osaka, Japan, in order to determine which environmental factors of wooded street are important as habitat of birds in winter. Eight species of 218 individuals were recorded at 2 times observation of the streets. I used a satellite image to identify the distribution of vegetation in my study area. The normalized difference vegetation index (NDVI) of each grid cell was calculated. The value of NDVI that indicated the threshold value for vegetation cover were 0.3 and more, based on the ground-truthing from December 2003 to February 2004. The proportion of vegetation cover within 50 m from a recording point was calculated in each bird species. The average vegetation cover proportion of Hypsipetes amaurotis and Sturnus cineraceus was more than 25 %, while that of Passer montanus was around 5 %. Almost all individuals of species except Passer montanus were significantly recorded in buffer areas within 100 m, 200 m, 300 m and 400 m from the edge of 2 ha and more woodlot.