Factors affecting tree invasion were analyzed at Ocitiai Pass in the area of Mt. Tsurugi Quasi-national Park in Shikoku, Japan. At the area, Abies homolepis has been invading into Sasa hayatae grassland. Pattern of A. homolepis expansion in the grassland was confirmed by comparing the distribution maps of 1954, 1962, 1975, 1990 and 2000, which were made by using aerial photographs taken in the years. A.rea of A. homolepis expanded with the year. Invaded area is decreased with the distance from the area where A. homolepis has existed in 1954. A model to estimate distribution of aboveground volume of S. hayatae was developed, in order to evaluate effect of Sasa covering the study area to A. homolepis invasion. Aboveground volume of S. hayatae could be categorized into 4 types in relation to relative photon fiux density at ground level; S_viI>18.5%, 10.6%<S_viII ≤ 18.5%, 5.5%<S_viIII ≤10.6%, and S_viIV ≤ 5.5%. Tree based model allowed to estimate the distribution of 4 Sasa-types for entire study area by using topographical index and index of wind velocity from southward as explanatory variables, which topographical factors were calculated from Digital Elevation Model (DEM). By overlaying the distribution maps of A. homolepis and Sasa-types, it was clarified that the rate of A. homolepis invasion was remarkably decreased in the Sasa-type S_vi IV because of the darkest light condition. In the S_vi I, invasion rate was slightly decreased comparing to the S_vi H & III, probably due to its stressful site condition; the most wind-swept and the driest in the area.

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In order to conserve and restore the habitat of a species for sustaining biodiversity, information on the species occurrence is essential, but there is little data regarding this. Producing a potentially suitable habitat (PSH) map is helpful for decision makers and land developers to establish strategies for conservation and for avoiding conflict of land use. The aims of this study are to i) establish a model for predicting PSH of endangered hygrophytes from species-occurrence data and several environmental variables, and ii) evaluate the degree of habitat loss in Tokushima Prefecture. The method for finding PSH is as follows; 1) Distribution data of target species are collected from specimens in the prefectural museum and field survey, and input into a GIS database. 2) Through CCA and cluster analysis, 66 target species are classified into ecological groups by using environment variables (stream power index, topographical wetness index, slope inclination, precipitation, elevation, etc.), and then factors limiting the occurrence of species group are identified using the index of electivity. 3) Areas with the same environmental sets preferred by each group are selected from entire region of Tokushima, and then potentially suitable habitat is found by overlaying the layers of selected areas. Geomorphologic characteristics of the PSHs of group A-D are as follows; the PSH of group-A is found at headwaters in mountain regions with gentle slope. The PSH of group-B corresponds with the area of flood plain formed by the Yoshino River. It is considered that temporary wetlands used to be created by frequent floods. Alluvial lowland areas around the mouths of Yoshino and Naka River acted as the PSH of group-C. The area is young, as it was formed within the last 6000 years after decrease of sea water level. The PSH of group-D is composed of various geomorphic types from lowland to mountain, and high areal ratio of gravel and rocky terraces is the characteristic of the area. Among group-D, it is considered that wetlands, which used be formed on the border between flood plain and terrace are the PSH of group-D1, and temporal wetlands formed at eroded areas are the PSH of group-D2. The area of PSHs of group B and C have been widely used as paddy fields and residential areas, and modernization of irrigation system and urbanization is ongoing. Thus the risk of extinction of the hygrophytes species is extremely high compared to the other three groups.

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Mukasa ruin of ancient mountain castle, located in Miyazaki, southern Kyushu, has been designated as a National Historic Ruin by Agency for Cultural Affairs, and requires an appropriate strategy of management. Management of this type of mountain castle ruin should take into account the two aspects of management objectives : preservation of topography (which itself has a historic value), and promotion of educational use. We aimed to propose a decision support model based on functional evaluation of site and vegetation conditions in relation to these two aspects, and to examine its usefulness by sensitivity analysis. Two axes corresponding to these two aspects were evaluated by scoring the relating topography and vegetation features hierarchically. In the scoring procedure, unchangeable factors such as topography or the academic value of each ruin part were weighed more than those which can be improved by management practices such as vegetation types or structure. Based on the combination of the scores of two axes, focal parts of the ruin area were classified into four types having different management objectives : 1) intensive management compatible with both conservation and educational use, 2) conservation-preferred management, 3) educational use-preferred management, and 4) less intensive management. This method was able to provide objective priority and required intensiveness of management simultaneously. Sensitivity analysis was performed by producing four different alternatives using different threshold scores for two axes. By overlaying the alternatives, several parts were extracted to have a consistent management objective throughout the all alternatives. These parts were considered to be the cores for establishing a management plan considering different potential opinions setting different priorities. These analyses enabled to provide information for efficient decision support.

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Phyllostachys pubescens Mazel ex Houzeau de Lehaie groves were cut down to clear abandoned bamboo groves in Japan. We examined vegetation changes and the regrowth of P pubescens two years after cutting at Oda, in Shimane Prefecture. Based on detrended correspondence analysis (DCA), secondary forests, P. pubescens groves and cutting areas were situated from large to small along axis I. The vegetation structure of a cutting site changed the relative positions of the P. pubescens grove and cutting site. At sites where the forest floor received more sunlight after cutting, the axis I score decreased, and the number of species that appeared increased. After cutting, the number of new P. pubescens shoots at cutting sites increased, and the new shoots were small. Two years after cutting, the number of ew P. pubescens shoots decreased but the shoots were larger than in the previous year. If cutting sites are not managed, P. pubescens groves may regenerate. Thus, sites should be continuously cut. Because the number of species that appear increases when forest floor illumination is increased slightly, cutting out P. pubescens culms of groves that grow among adult trees on the forest floor is useful for recovering broadleaf woodlands.

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The effect of water flow conditions on the feeding behavior of herbivorous fish in Phyllospadix japonica meadow was studied in October 2005 in Old Islands, Shimane Prefecture, Japan. P. japonica distributed between-0.5 m and-3.7 m relative to datum level. Leaves with distinctive bite marks by the herbivorous fish were found throughout expansive areas vegetated by P. japonica. At the areas in which bite marks on the leaves were confirmed, the plant size of P. japonica was small. P. japonica exposed to greater water flow condition experienced less grazing compared to low flow areas that were grazed. This result indicated that herbivorous fish seemed to avoid the areas exposed by increased water flow.

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