Wildfire potential is high in Naoshima because of climate condition. It is endorsed by the number of wildfire events. Since 1976, wildfire has happened seven times. To keep sound forest environment, forest must be maintained properly not to be fragile against fire and to be strong enough to recover as soon as possible after wildfire. In this study, we estimate prior vegetation condition in terms of burned severity and the potential of recovery using in-situ data and Terra/Aster satellite data.

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From 2005 to 2006, we investigated the effects of dominant tree species in canopy, the present and the past forest floor management, and light environment on bolting population and flowering of Lilium auratum Lindley at the forest on the ridge in Musashi-Kyuryo National Government Park in Saitama prefecture, Japan. The results show:1) more than 9 year duration of mowing increases obviously bolting population, flower-bearing population and the number of flowers per individual, whereas 2 year duration of mowing is not enough to increase them; 2) among 2, 1 and 0.4 times a year mowing, the more frequency of mowing is conducted, the more bolting population, flower-bearing population and the number of flowers per individual increase; 3) the growth of L. auratum is suppressed where deciduous broad leaf trees such as Quercus serrata Thunb. are dominant in canopy compared with where Pinus desiflora Sieb. is dominant because less light reaches the forest floor.

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A 12-years monitoring was conducted of a bamboo forest adjacent to a deciduous broad-leaved forest to clarify the bamboo stand dynamics during its expansion into an adjacent forest. The bamboo forest gradually expanded its area into the deciduous broad-leaved forest at an invasion rate of 7 m over 12 years. The density and aboveground biomass of bamboo living culms in the study plot increased. Conversely, the understory trees' density and species number decreased. The mean diameter at breast height (dbh) of living culms did not differ between the interior zone and the periphery zone of the bamboo stand through observation. Although increment number and aboveground biomass were constant in three innermost sub-plots, they were markedly increased in outer part, which increased understory trees' mortality.

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We researched the internal genetic variability of Ludwigia peploides ssp. stipulacea which was designated as a vulnerable plant species in Japan. The samples of 11 sites in Chiba, Kanagawa, Kochi and Miyazaki pref. were analyzed by Randomly Amplified Polymorphic DNA (RAPD) method. PCR produced amplified DNA with 10 out of 18 primers. The closely related species L. adscendens misses the some major bands which presence in all samples of L. peploides ssp. stipulacea in 5 cases of PCR. These can be used as differential DNA markers between two species. Only one primer showed DNA polymorphism of major bands, especially, differentiating group of south Miyazaki and Muroto Cape from others. However, since most major bands are common among samples, it was clarified that the internal genetic variability was relatively low in this species. This is a result of supporting the hypothesis of Maekawa (1943) who assumed the prehistoric naturalized plant as for L. peploides ssp. stipulacea. We discussed the distribution process of this plant species in Japan after introducing with the rice farming.

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Application of porous concrete to vegetation-covered revetment structures is increasing. However, there are only limited numbers of quantitative reports on the effects of POC flumes on restoration of ecological habitats. POC flumes were surveyed and compared with conventional concrete flumes and earth flumes. It has been demonstrated that rich ecological habitats can be established more quickly and securely in POC flumes than in conventional concrete flumes. Three major environmental elements such as vegetation, mud and grit are observed in POC flumes, and biodiversities are being kept.

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Many introductive monitoring studies about ecological corridors had been reported just after construction of corridors. However, it is necessary to inspect effects for habitats from a long-term point of view. This study intended to grasp effects of the bridge for animals at the habitat of Japanese squirrel, Sciurus lis for eight years after construction. We investigated the habitat site condition and the use of the bridge for animals using a video camera. As a result, the bridge for animals has been used after having passed for eight years, and it became clear to have function as a corridor of the habitat. The function as a corridor is for daily trip and seasonal trip. Therefore it was supposed that the bridge for animals was effective in avoiding extinction of the Japanese squirrel population in this area.

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The purpose of this study is clarification of the growth and development of Oxalis articulata Savigny as a promising ground covers. We examined the effect of day-length and temperature on the growth and flowering of O. articulata. As a result, it was a long-day plant at 20 degree C. It seemed that there was the critical day-length during 12 hours from 13 hours at 20 degree C. In addition, the long-day treatment was able to replace it in night break treatment. On the other hand, the dormancy of O. articulata observed after rainy season in the outdoor culture was considered to be imposed dormancy induced by higher temperature of the season.

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The effect of the supporting materials on the training of shoots in the production of potted Hedera helix cuttings was evaluated. Stalks made of Chamaechyparis obtusa woods with or without coconut-fiber mats (CMF) were used as supporting materials (props). The aerial roots adhered to the surfaces of props and radiated in all directions on them in the case where props without CFM (x-props) were used. On the other hand, aerial root extended to the surfaces of mats and penetrated into coconut fibers when props with CFM (y-props) were used. The ratio of rooted cuttings that adhered and climbed up to the top of the stalk was 33 % when x-props were used, while about 70 % in the case of y-props. In the case where no props were used, some shoots extended horizontally and twisted with the next shoot. In addition, some shoots with aerial roots touched the medium of other pots, and the roots grew into the medium. From these results, it is suggested that the use of props made of C. obtusa woods are useful in the production of potted H. helix cuttings.

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We clarified the characteristics of wood chip composting mixed with sewage sludge compost by comparison with normal bark composting. The carbon decreasing and the nitrogen increasing in wood chip composting mixed with sewage sludge compost were larger than those in normal bark composting. Compost temperatures in wood chip composting were higher than those in usual bark composting. Sewage sludge compost as submaterial increased the exchangeable Mg and the base saturation percentage of the compost compared with the compost using the other submaterials. In wood chip composting, using fermeted fowl dropping and urea for submaterial decreased CEC and temperature due to inactivation of microbial activity compared with using sewage sludge compost. Therefore, it seemed that sewage sludge compost had been suitable for submaterial of wood chip composting.

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In order to discuss the conservation of endangered species and the restoration of vegetation in a river flood plain, we conducted germination tests and vegetation and site condition surveys, which included ground-water level and submergence frequency data. Since ground-water level and submergence frequency depend on the height of the ground, moisture conditions in the area investigated are strongly influenced by the height of the ground. In addition, since there is a close relationship between the distribution of existing vegetation and the characteristics of the germination of buried seed, the species composition of existing vegetation is decided by differences in the moisture condition when buried seed germinates.

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We compared seedlings growth from (1)soil seed bank and commercial seeds (2)cultivative base of organic matter and that of organic matter with mineral soil in revegetation methods. The results of monitoring for 4 years were as follows; 1) species richness of soil seed bank of two revegetation methods were 2.8 and 5.2 times more than those of commercial seeds. 2) number of seedlings were 6.0&sim:17.5 per 1m² in soil seed bank plots. And indices of biomass 4 years after construction in soil seed bank were similar to those of commercial seeds. It would be possible to make diverse both landscape and plant community by soil seed bank.

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The performance of the combination of high density unwoven cloths of which water retention performance is high and a mat plant was estimated. This system is expected as a thin-layered growing system for various kinds of ornamental plants on green roof. The unwoven cloth of 4 cm in thickness was the most effective for growing of Ophiopogon japonicus f. nanus and Phyla canescens among that of 2 cm and other kinds of water retention mats. O. japonicus and P. canescens could grow without irrigation, although they grew best with irrigation of once per 2 weeks or 2 times per week, respectively.

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We measured evapotranspiration rate of several rooftop gardening plants in order to obtain basic data to quantify the effects of rooftop gardening on thermal environment of the building. We set up rooftop gardens with 2 kinds of soils, natural soil (Andisol) and artificial potting soil (Perlite-based commercial product), in 3 different thicknesses (7cm, 14cm and 21cm). Three species each of common gardening plants that are suitable to each soil thickness were selected and grown in stainless steel Lysimeters buried in the experimental plots. The decrease in weight of Lysimeters was measured as evapotranspiration rate. Evapotranspiration rates of several plants planted at natural soil plots were less than those of the same species planted at artificial soil plots since their conditions were bad. Evapotranpiration rate of Verbena × hybrida planted at natural soil plot was less than the amount of water evaporation from bare soil. In August, the transpiration rates of Rosmarinus officinalis L. planted at artificial soil plot was 7.2 kg/m²/day, that of V. × hybrida planted at artificial soil plot was 12 kg/m²/day, and that of Rhododendron pulchrum Sweet cv. Oomurasaki was 14 kg/m²/day. Those were the highest rates at the plots of each thickness.

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This study aimed to quantitatively assess the effects of wall greening systems in mitigating the thermal environment by measuring the evapotranspiration from wall panels on which Eurnomymus fortunei was planted, and calculating the latent heat flux from the evapotranspiration measurements. The analysis showed that 1) the evapotranspiration from the panels, which used peat moss as the growing media, was about 4.1kg/m²(4.1mm), the transpiration from the plants was about 2.4 kg/m²(2.4mm), accounting for 60% of the evapotranspiration, and 2) there was a positive correlation between the latent heat flux and the net emission, and the latent heat flux from the panels was about 60% of the increment in net emission. The study suggests that the effects of wall greening in controlling latent heat and s mitigating the thermal environment can be quantitatively assessed by calculating the latent heat flux of panels from measurements and analyzing the heat balance.

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There is a correlation between evapo-transpiration, soil water, and vegetation cover. Evapo-transpiration was measured in the three different cover types, soil, Sedum, and Zoysia. Evapo-transpiration was increased with less than 0.3 g cm^-3 of soil water. The lower temperature of vegetation covering and soil surface caused by increasing of evapo-transpiration. However, temperature decreasing did not depend on the plant species, such as Sedum, and Zoysia, and soil type. The light spectrum was related to the different amounts of soil water and it was increased in near infra-red range by increasing of soil water.

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Generally, landscape design for a rebuilding housing complex, transplanting existing trees has not been considered positively because of difficulty in restoring root system and slows in recovering crown shape of trees after they are transplanted. The purposes of the present study were to follow the 162 deciduous trees transplanted from rebuilding housing complexes and to suggest the future directions of transplanting trees. Our result demonstrated that 92.6% of transplanted trees were successfully established and recovered the crown shape in four or five years. It became clear that the transplanting existing trees in rebuilding housing complexes is considerably recommended judging from the establishment and the recovery of crown shape of each tree. Additionally, Zelkova had the higher score in restoring crown shape among the deciduous trees.

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Planting bed soils in block parks are often compacted by machine earthwork or human tread etc. Generally, soil that is too hard slows the growth of root system and is harmful to tree health. In order to specify which soil layer affects the vitality of Prunus yedoensis, soil hardness was measured to a depth of 60cm under 375 sample trees in 69 block parks in Tottori City. At the same time, vitality of each sample tree was evaluated visually. The chlorophyll amount (SPAD) of 30 leaves from each sample tree was also measured. Consequently, it become clear that the soil layer that most affected tree vitality, was in the range of 10-30cm below ground level, particularly 10-20cm. There was also a significant correlation between degree of tree vitality evaluated visually and by SPAD. Therefore, SPAD can be used as an quantitative indicator of tree vitality.

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We examined the growth of the root of cuttings of Osmanthus fragrans var. aurantiacus cutting transplanted in April, July and August in 2005 after they had planted temporarily. The amount of the extension, the thickness, the ramifications and dry weight of the expanding root outside the root pots of cuttings were measured two, four and six weeks after they were transplanted. As a result, the difference at the transplant time was considered to affect the growth of the first root and the second root, the elongation growth and the thickening growth of the root.

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In this study, photosynthetic characteristics and water use efficiency through the light response curve of Caatinga trees were examined and their growing situation on local environment was discussed. Jurema preta showed a highest maximum net photosynthetic rate and high light compensation point. It is considered that Jurema preta play one of the pioneer plant. There was no significant difference between Algaloba and Jurema preta in terms of maximum net photosynthetic rate and water use efficiency. Catingueira showed a lower maximum net photosynthetic rate. However, Catingueira exhibited a lower light compensation point than Jurema preta. It is considered that on the succession process, Jurema preta plays a leading role and dominant in the early stage. Following Jurema preta, Catingueira became dominant. Pinao bravo showed lower water use efficiency than Jurema preta. It's considered that Jurema preta become dominant following Pinao bravo when Caatinga vegetation was damaged by the drought. Considering the revegetation plan for recuperation and preservation of Caatinga vegetation, it seems to be better use the dominant species in the later stage such as Catingueira. On the other hand, for reproduction, it would be better to use the species that exhibit high photosynthetic rate, such as Jurema preta.

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This study aimed to examine the effects of warmer conditions on the growth and the phenology of three–year–old Acer rufinerve Sieb. et Zucc. seedlings. The growth and the phenology of Acer rufinerve were investigated under several controlled temperature conditions of outdoor temperatures altered by ±0.0°C, +1.0°C, +2.0°C, +3.0°C. The results indicated that, main shoot elongation, diameter increment became the same among treatments. But dry weight of each organ, the rate of transpiration, the number of nodes and leaves were decreased under warmer conditions. Advance of autumn leaves and leaf shedding under +2.0°C – +3.0°C treatments were overdue. And, some of leaves under +3.0°C treatment didn′t shed. It seemed that the growth and the phenology of Acer rufinerve seedlings should change under warmer conditions.

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This studies aimed to examine therelationshipbetween floweringof Lycoris radiata Herb. and temperature, and weconducted a growth experiment in the artificial weather rooms. The growth of Lycoris radiata were investigated under several controlled temperatures. Conditions were altered by ±0.0°C, +1.0°C, +2.0°C, +3.0°C of outdoor temperature. And the day that temperature condition alterationwas on Jun.6, Jun 28, Jul.15, Aug.4, Aug.26, to Sep.5, 2005. As a result, the test plants were able to flower under warmed conditions from summer to early autumn, too. Especially, the test plants grown under +1.0°C to +3.0°C from Jun.6 to Jul.15 were able to flower under warmer condition. It was indicated that the flowering temperature increased with the rising summer temperatures. It seemed that the rising of the average temperature from +1.0°C to +3.0°C in the summer didn't influence to flower conditions.

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Gynodioecious Dianthus superbus L. var. longicalycinus (Maxim.) Williams, has been endangered along the Tama River, Japan. We examined the germination traits of hermaphrodite-derived seeds and female flower-derived seeds in a laboratory experiment using a gradually increasing and decreasing temperature method. In our germination experiments, it was showed that this plant doesn't have mechanisms to maintain persistent seed banks; it would be important, therefore, to conserve the existing individuals and their habitat. Restoration of populations with seed banks would be difficult. Restoration efforts for this plant should include dispersal of cold-stratified hermaphrodite-derived seeds and female flower-derived seeds in spring.

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Growth of Pinus densiflora SIEB. et ZUCC. seedlings were investigated grown under several controlled temperature conditions of outdoor temperatures altered by +4.5°C, +3.0°C, +1.5°C, 0.0°C and -1.5°C. As a result, growth initiation timing became the same among treatments. Dormancy of winter buds were not released much because of shortage of winter chilling in the high temperature treatments. Shoot length and the number of needle leaves became to be smaller under +4.5°C treatment caused by inhibition of leaf primordia formation and elongation of lammas shoot under warmer condition in the previous year.

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Using the pressure-volume technique, the effect of drought stress on leaf water relations was investigated in cuttings of two willow species, Salix psammophila and S. matsudana, both of which have been widely planted in the Mu-us sandy land of Inner Mongolia, China. Under the moist soil water condition, S. psammophila and S. matsudana showed high values of leaf water potential at the turgor loss point (φ_w^tlp) and osmotic potential at saturated point (φ_s^sat). Shoot growth and total biomass of both species were decreased in response to drought treatment. The results suggest that both S. psammophila and S. matsudana are sensitive to drought. It was also observed that φ_w^tlp and φ_s^sat in S. matsudana markedly decreased during the drought treatment period whereas those in S. psammophila showed very little changes, implying a higher ability of osmotic adjustment for S. matsudana than for S. psammophila.

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Forest structure and growth of individual trees were investigated by enumeration survey and stem analysis in the windbreaks established and left free for 15 years in Mu-Us desert in Yinchuan City, Ninxia-Huizu Autonomous Region, China. 40 % of planted Populus alba var. pyramidalis reduced because of self-thinning promoted by severe intra-specific competition for natural resources. Survived trees showed the vigorous growth reaching higher than 12 meters. On the other hand, self-thinning was seldom occurred in both windbreaks of P. Opera and P. hopeiensis. They had a lot of dead branches on their crowns and their annual height growth showed an asymptotic curve to the 7 to 10 meters maximum height. Soil moisture content was lower in P. alba var. pyramidalis forest than in P. Opera and P. hopeiensis forests, because of more water consumption of P. alba var. pyramidalis by great volume of leaf biomass.

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Leaf water potential was compared among exotic Robinia pseudoacasia L. and 13 native woody plants, including Quercus liaotungensis Fish., at Mt. Gonglushan (N36°25′40", E109°31′53", alt.1353 m)near Yan′an city in the Loess Plateau of China, where desertification is now in progress. Predawn and Mid–day leaf water potentials of exotic R. pseudoacasia were lower than those of native Q. liaotungensis on August 2002. Among native woody plants, 5 species of shrubs and subtrees showed very low mid–day leaf water potential of less than -3.5 MPa. These results showed that exotic R. pseudoacasia was growing under strong drought stress compared to native Q. liaotungensis. However, the environmental condition of native shrubs and subtree species was severer than that of R. pseudoacacia.

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Soil carbon, nitrogen and phosphorus were measured for sloping fields, terraced fields, grassland and woodland in Liudaogou Village, Shanxi Province,. The growth condition of planted Pinus tabulaeformis was also studied. The carbon and nitrogen contents of sloping fields and terraced fields were very low as 0.3% and 0.03%. Those were increased about twice in woodland and grassland. Tree height of Pinus tabulaeformis was less than 4m, and the annual extension of stem was less than 20cm. On the same micro-topographical type, the growth of Pinus tabulaeformis was affected by soil hardenss.

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In order to obtain the knowledge about the soil improvement by using earthworms, the change in the chemical and biological properties of soil added earthworms were investigated in a field. The effects of earthworms on the soil improvement were compared between the earthworms living in the litter layer and the earthworms living in the mineral soil layer. The influence of soil temperature on the activity of earthworms were studied. The earthworms living in a mineral soil layer enhanced the microbial activity, compared with the earthworms living in the litter layer. It suggests that activities of earthworms in the soil layer promoted the soil improvement than earthworms living in the litter layer. Moderation of soil temperature by shading in summer kept the high concentration of nitrate ions in the soil solutions. It consequently suggested that soil temperature affected on activating microorganisms by earthworms.

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Topsoil of Quercus variabilis-domninated secondary forest was spread on a cut slope for revegetation in a developing new town area in urban Osaka. For seedling observation, seventy-five subplots(1 m×1 m) in a cut slope plot, 300 subplots(1 m×1 m) in the Quercus stand plot were established. We recorded species and number of woody seedling. Forty-three species and 807 seedlings in the Quercus plot, 48 species and 1,105 seedlings in the cut slope plot were observed. The numbers of pioneer seedlings in the cut slope plot were significantly higher than in the Quercus plot. The numbers of seedling of Caprifoliaceae, Aquifoliaceae, Cornaceae and Theaceae were significantly higher in Quercus plot than in the cut slope plot. So it appears that these species have difficulty to emerge on a slope where soil is liable to dry condition.

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We analyzed the transition of spatial distribution and area of gullies at Mt. Yotei, Hokkaido Prefecture. For the analysis we created database of aerial photographs from 1963, 1977 and 1992, using GIS. As a result, we found that there were 18 gullies on the north and 20 gullies on the south side slope, but that they were generally decreasing in area. However, some individual gullies expanded temporarily. In elevation divisions, the area of gullies has decreased most in the region under 500m in elevation. A decreasing tendency was also observed above 1,500m, but the rate of decrease was low. This may be attributable to the influence of freezing and the spring melt, and the lack of soil and vegetation there. The area of gullies was decreasing on both the upper and lower sides of the forest limit, but the rate of decrease on the upper side of the forest limit gradually tapered off. The decrease of gullies was especially noticeable below dams at the most upstream, showing the effect of dams in preventing gullying.

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The Tanzawa mountains is important water source forest area in Kanagawa Prefecture. However, it is the place where the landslide and mudflows occurred frequently by the Great Kanto Earthquake in 1923, and subsequent heavy rainfalls, etc. It is thought that sufficient water and soil preservation function is not exhibited because many landslides remain still now. The purpose of this study is to clarify the vegetation recovery process of landslides in Nakanosawa watershed(370 ha), Kurokura basin. Changes of the landslide feature by aerial photographic analysis and field survey which investigated the vegetation recovery of remained landslides were performed. The difference of landslide area between the recovered landslide by vegetation for a short period and the remained landslide is not found. Slope angle, slope direction and altitude of the landslide were greatly involving as a factor of vegetation recovery.

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