In this research, we selected umbrella species for conserving the diversity of all woody plant species, using the presence/absence dataset of woody plant species in the 21 fragmented shrine forest patches in the urban and suburban matrix of Kishiwada City, southern Osaka Prefecture, Japan. The selection method for the umbrella species is based on the “focal species approach” developed by Lambeck (1997), and multispecies most sensitive to each threat category were chosen as the focal species. The results showed that the most sensitive species against decrease in forest area were Damnacanthus indicus and Ardisia pusilla, and that the most sensitive species against increasing isolation distance were D. indicus, A. pusilla, and Callicarpa mollis. The conservation planning guidelines we derived from these 3 focal species were as follows. (1) Conserve or create forests at least 0.82 ha in size and (2) conserve or establish woodland patches that are within a minimum distance of 0.80 km from large forests. It was revealed that over 90% of indigenous woody plants can be conserved by adhering to these guidelines.

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To clarify the shrine forests provided various plants’ habitats, we surveyed the plant species composition, light environment, and soil water content in 75 stands. Fifty of these stands were located in shrine forests and 25 were located in other sites in Matsumoto City, central Japan. All shrine forests had a tree canopy layer of Cryptomeria japonica, Chamaecyparis obtusa, or Zelkova serrata, and various species on the forest floor. Compared with other stands, shrine forests had a rich assemblage of forest-interior on maintains and forest-margin species, but few roadside species. The rates of naturalized alien plants were low in shrine forests because of the closed canopy and moderate shade conditions on the forest floor. Some shrine forests had high soil water content and many plants that would grow in wet sites. Thus, shrine forests have an important role as habitat for various native plants within city environments.

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This research investigated the change of weeds community by winter-flooded that conducted at shore of Inba Lake, and compared to the different of weeds community in dry-rice-field. As a result, we could confirm empathic difference between winter-flooded rice field and dry-rice-field. In regard to species number per year, winter-flooded rice field intended to be fewer in comparison to dry-rice field. In regard to the plants volume, although winter-flooded rice field were higher than dry-rice field at summer, otherwise dry-rice field were high. In winter-flooded rice field, plant volume of Monochoria vaginalis which was dominant at summer and autumn extremely increased, and in winter, plant volume of Alopecurus aequalis which was dominant species in pre-winter flooded extremely decreased.

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Technological study and consensus building process were facilitated to support the conservation of rural pine forest and the utilization of slash biomass produced by the activities of a local volunteer group. Specifically, a cruise survey of standing and fallen trees in 13 plots and a cutting survey of the major tree species in the group activity area were performed. The results of the surveys confirmed that (1) 9 species of trees constituted 91% of the standing trees, expressed on the basis of basal area, and (2) the basal area of each tree among these species showed a high correlation with the available tree biomass. In addition, the vegetation in the area was classified into 3 types on the basis of the crown density of the pine trees in each cell of a 20 m grid layer, with overlaying on digital aerial photographs. Thus, the available tree biomass, including the fallen trees of each vegetation type, was estimated to be 155.5-201.9 tDW/ha by conversion of the abovementioned relational expressions from a basal area to the available tree biomass. Subsequently, the total available tree biomass was estimated to be 3065.0 tDW/ha by conversion from the aggregate area of each vegetation type. In a workshop cohosted by researchers and the volunteer group, these results were used for consensus building between the parties, after specific suggestions had been made regarding the target value for maintaining the forest stand on the basis of the practical uses of the biomass.

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