Pull-out resistance of root system, as a total force concerning to slope stability and tight binding power of soil, among major planted species in post-fire stands for erosion control projects by Hiroshima prefectural government, were evaluated. The species differences of relationships between root diameters and maximum pull-out resistance loads were confirmed especially in larger diameter degrees and could be approximated by exponential curves. The differences were also assessed by distribution of estimated pull-out resistance of sample trees. From basis for these comparative differences among species, planting methods should be adopted in the projects, in consideration of the future target of forest types and succession process.

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The technology that manages to alien revegetation species Amoerpha fruticosa L. community is important factor. The purpose of this study was confirming the effect the management of Amoerpha fruticosa L. We measured dead population and sprouts of Amoerpha fruticosa L. Five types of experiment plots were set in the cut-slope. Treatments of each plot were 1) cut down once in spring, 2) cut down twice in spring and summer, 3) cut down and spread herbicide once in spring, 4) cut down and spread herbicide once in summer and 5) cut down and spread herbicide twice in spring and summer It was clear that treatments 4) and 5) were able to exterminate Amoerpha fruticosa L. population by approximately 60%, and were able to reduce sprouts more than other treatments. Therefore, we concluded that treatment 4) was most efficient and effective method.

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To get fundamental knowledge about the earthworm, we investigated the relation between the habits of earthworm and types of vegetation. Earthworms were counted for about one year in various vegetation types. In forests which are formed by Hinoki cypress or pine, few earthworms were found. In forests which were formed by cedar or deciduous trees, there were a lot of earthworms. And it was guessed that earthworms can winter in the evergreen forests, but are hard to winter in the deciduous forests or grassland. According to the analysis of soil properties of the same study sites, the exchangeable Ca contents are less in the forests that few earthworms were found. And it was suggested that there were the relations of the trade-off between the number of earthworms and the microbial activity or the number of fungi.

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We investigated the effects of soil physicochemical properties on forest restore in Miyake Island. The plot of the thick and very hard volcanic ash sedimentation had poor N mineralization in the ash layer, so herb and fern were not able to restore. Alnus sieboldiana grew a lot by their root nodule in the plots. The mineral soils were rich in the plots. On the other hand, the plots of the thin ash sedimentation had acid and poor N mineralization in the mineral soil. Because there were grown thick Miscanthus condensatus and Histiopteris incise, trees restore were very slow.

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Tamarix austromongolica Nakai is distributed from north China to Mongolia, and has high salt tolerance. In this study, effects of salt composition in soil on the salt composition in plant and secreted salt of, T. austromongolica were examined using the cuttings grown at salinities of 10,000 ppm (NaCl : CaCl₂ = 2:2), 7,500 ppm (NaCl : CaCl₂ = 2:1) and 7,500 ppm (NaCl : CaCl₂ = 1:2) of irrigated water. 1:2 treatment had more Ca²⁺ in soil than other treatments. In 1:2 treatment which had higher Ca²⁺ concentration in soil than other treatments, Na⁺ concentration in plants was lower than others. Therefore, Ca²⁺ might inhibit the absorption of Na⁺. Furthermore, in all treatments, more Na⁺ were contained in secreted salt than plants. Therefore, T. austromongolica might be able to selectively secrete Na⁺ from salt gland.

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We investigated the relationship between groundwater level and distribution of Cynanchum komarovii in Musu sandy land. As a result, relative elevation at which C. komarovii was distributed ranged from 68 cm to 314 cm at this study area. The dry weight of C. komarovii was highest at the lower part of sand dune, where the relative elevation from groundwater level was 140 cm. The number of species was lower at the bottom of the sand dune than at other level. According to the groundwater level and the distribution depth of stem and root, it was thought that C. komarovii adjusted by extending the stem to sedimental sand, and grew while using underground water. We consider it could be suitable for use as a ground cover at sites affected by overgrazing in semi-arid land.

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For the conservation of the population of Malus sieboldii around Konbukuro Pond in Kashiwa city, the genetic structure and the morphological diversity of 7 populations of Kanto district was studied. Based on the allozyme analysis, Expected heterozygosity of total populations was high as 0.22, compared with other dicotyledon species. That of Konbukuro population was 0.247 and the highest among the studied popultations. In the dendrogram constructed based on denetic distance, the population of Konbukuro was classified in the east Kanto group. However, the morphological property of flower of Konbukuro population had unique characteristics irrelevant to geographic group derived from genetic study. Consequently, the population of Malus sieboldii around Konbukuro Pond has not genetically deteriorated, and it is appropriate to propagate saplings from the native population of Konbukuro to restore this population.

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Penthorum chinense Pursh were transplanted to the artificial planting ground at the waterside of the reservoir. The selective weeding of oppressive herbaceous plants had done for initial 3 years and the sweeping weeding had done in early spring for 5th to 8th year. No management had done since 9th year. The number of P. chinense had decreased since 3th year and had disappeared in the many quadrats since 9th year. On the other hand, The number of P. chinense had increased in the added quadrats where litters were removed early in spring and plants except P. chinense were weeded early in summer. These results suggest that the adequate condition for germination and the removal of competitors in the growth stage are important for perennial appearance of P. chinense. Many seeds of P. chinense were buried in the soil of the planting ground and germinated when the top soil were cultivated. Though seeds of P. chinense were germinated in the water, the seedlings did not grow.

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Changes of the habitat and inhabitation of Trapella sinensis Oliver, an endangered species were investigated in Hokkaido, the northernmost distribution in Japan. We also investigated transplant conditions of water depth, and morphological characters of fruits and seeds from the cleistogamous flowers among Hokkaido's, Okayama's, and Saga's. As the results show; open water area, density of individuals, and number of cleistogamous flowers in the habitat were highly decreased in recent. It is also clarified that the habitat in Hokkaido has a drought period unlike the others. In the transplant experiment, only low water depth plot (water depth:40 cm) showed high values of survival rate, coverage, and number of cleistogamous flowers. In addition, the morphological character, especially, number of awns of fruits in Hokkaido was almost same as in Saga. For the conservation of T. sinensis, we proposed an idea that river improvement works, dredge basins and borrow area in river area should be used as a new habitat of Trapella sinensis and other riparian organisms.

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This study focused on factors and conservation practices for vegetational zonation on the Enshu-nada coast, Shizuoka Prefecture. The vegetational zonation was distributed into four zones in order of Carex kobomugi, Ischaemum anthephoroides, Fimbristylis sericea and Imperata cylindrica in a direction from shoreline toward inland. It was discovered that the distribution of each zone was influenced by ocean waves and sand deposition. Furthermore, it was found that a seashore width of 100m or more was necessary for zonation by Classification Tree Analysis. For example, it was observed that the Fimbristylis sericea zone was absent in areas less than 100m of seashore. As a result, it is considered important to maintain a seashore width of 100m or more in order to conserve the zonation on the Enshu-nada coast.

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Euonymus sieboldianus Blume seeds are thought effective for long-term storage under cold and wet conditions; however, the seeds easily rot under wet conditions. Thus, here, seeds were stored under 21.3 % moisture content under cold conditions; nevertheless, the germination rate decreased. Considering the decrease in the germination rate to be due to secondary dormancy, cold stratification, warm stratification and gibberellic acid (GA3) treatment were carried out on dried seeds. As a result, cold stratification for 3 months with GA treatment was found to increase the germination rate. However, neither individual application of cold stratification, warm stratification or GA treatment, nor cold stratification for 2 months with GA treatment had a significant effect on the germination rate. Furthermore, no effect was found when warm stratification was used. In addition, the germination rate was significantly higher at a GA treatment concentration of 1,000 ppm than at 100 ppm and 500 ppm.

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The native Chinese tree, Catalpa ovata G. Don, often planted for medicinal and ornamental purposes, has recently invaded floodplain areas. To estimate the extent of its expansion, we investigated the distribution of C. ovata along the Tama River. We also examined the germination rates of two seed types (collected at different times) under various light and temperature conditions. The distribution of C. ovata ranged from 22.8 to 60.2 km (with the highest concentrations from 43.7 to 60.2 km) from the river mouth. The suitable temperature range for germination was 30-35 °C, and germination rates were high in alternating temperature conditions. Germination rates did not substantially differ between brown and green pods that were collected at the different times. The ability of seeds from green pods for the flooded season to germinate suggests that the area of distribution of C. ovata was expanded by flooding.

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There are many endemic species on islands. To conserve biodiversity, people and endemic species must coexist. We investigated the relationships between the distribution, growing conditions, and surroundings to further the conservation of the endemic variety Lilium auratum Lindl. var. platyphyllum Baker on Izu Oshima Island, Japan, in the special protection zone of a national park. The variety grew best in early successional vegetation in which the dominant species was Miscanthus condensatus Hack. The suitable vegetation was limited to a small area in the special protection zone, within which the distribution of L. auratum was limited to a smaller area.

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Tortula pagorum (Milde) De Not. is an exotic bryophyte species. The purpose of this paper was to reveal the habitat preference of this species, and evaluate the impact of this exotic species on native bryophyte species. The study sites were fragmented forests in Kyoto city. We found that the chances of invasion rather than environmental conditions were important factor for the distribution of this species. As far as we observed, it is likely that this species was not a menace to native species at present. However, long term monitoring of the invasion process is needed to evaluate the impact of this species to native bryophyte species.

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Classification tree model was developed using distribution data of T. dentata and current climate dataset. The suitable habitats (SH) in Japan under current and climatic change scenario (RCM20) were predicted using the model. The model, deviance weighted score and predicted SH revealed that the influential climate variables for the distribution were WI(warmth index) and PRS(summer precipitation) mainly, and PRW(winter precipitation) and TMC(minimum temperature for the coldest month) locally The number of second mesh cells of SH under current, 2031-2050 and 2081-2100 of RCM20 scenario was 1,388, 2,179 and 2,813 respectively. The suitable habitats were predicted to shift whole Honshu except high mountain region and Hokkaido, and to reach northernmost of Honshu.

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We conducted vegetation and bird surveys on forests, farmlands, villages and so on, on Keihanna Hills, in order to test configuration patterns of landscape factors of secondary nature, and the relationship between these patterns of habitats and birds. As the results of the vegetation survey, we found that strong negative correlation existed between % rice paddy and % tree cover, and that when % tree cover was medium, mosaic structure was most complicated, and length of forest edge was longest. We made several regression analyses on bird species richness, with explanatory variables adopted from among vegetation variables. We found that % tree cover was important for total bird species richness per plot; however, species richness of non-forest bird species was negatively affected by % tree cover. We also conducted regression analyses on total individual numbers of several bird species per plot. We found that assessment of vegetation on a fine scale is effective for understanding landscape factors of secondary nature.

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This study's purpose is to clarify the effects of differences between greening conditions on building sites, roof-tops and walls of buildings on the thermal environment using CFD (Computational Fluid Dynamics) analysis, and with the Kasumigaseki district in Chiyoda-ku, Tokyo as the model. As a result, the quantity of total sensible heat flux, was 24% lower in the case of lawn greening and roof-top greening in the district than in the case without greening. In addition, in the case of wall greening at the south and west side of each building, it was lowered by 15%. In this way, the thermal effect of greening of the building site in the actual district could be grasped quantitatively.

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A new media hardened by heat fusion polyester fiber has a characteristic that stanch the flow of media materials by watering. By raising bedding flower seedlings in the media, these materials were bound strongly with the growth of the plant, and penetration resistance of the media grew stronger. Pretreatment of slow release fertilizer for the media, it could keep flowering on the seedlings by only watering. 9 cm diameter size media just fitted on 5.5 cm pitch net-fence. This media was able to make wall greening quickly without using new base or soil. In summer high temperature, to keep the media wet condition and to send wind for them, the temperature of media were cold down and the ambient temperature of greening face was also cold down.

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There is uncertain information that sweet osmanthus (Osmanthus fragtans var. aurantiacus) trees may show twice flowering peaks. To clarify that, we measured the number of floral buds, flowering floral buds and flowering florets of sweet osmanthus trees used as garden or landscape trees in the north residential area of Kyoto City. Results showed that most of trees investigated reached a peak of flowering twice October 11th and 23rd, 2007. It is considered that many people do not know the twice flowering of the sweet osmanthus because the number of flowering florets and amount of fragrance on trees in the second flowering peak were less than those in the first. On the osmanthus trees, flowering florets were observed on both the current shoot and the 2^nd-year shoot and these florets derived from the axillary buds and also the adventitious buds. In addition, floral buds on the 2nd-year shoot contributed to the second flowering peak more than those of the current shoot, and also of those adventitious flower buds do so than axillary buds. The adventitious buds seem to be deeply-involved in the second flowering peak of sweet osmanthus tree as the current shoot tends to make adventitious buds more easily than the 2nd-year shoot.

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Trachelospermum plants can climb by both aerial roots and twining stems, so, they are expected to be effective for covering both walls and fences. In Japan, T. asiaticum, T. jasminoides, and T. jasminoides var. pubescens are commercially distributed. These species are often confused with each others when they are used as landscape plants because it is difficult to identify them individually. This study compared characteristics of vegetative organs of the genus Trachelospermum Lem. using native specimens from the middle Kinki district and plants commercially distributed in Japan. The results suggest the useful indexes of vegetative organs for easy identification of 2 species and 1 variety in adult phase. Furthermore, we declare the difference between adult plants and juvenile plants in T. asiaticum and T. jasminoides var. pubescens.

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This study evaluated the effect of the reduction in atmospheric CO₂ by a planting model of detached houses. The CO₂ reduction effect was evaluated by the amount of CO₂ fixed by planting trees and by the shading effect of planting trees reduced air conditioning energy. The CO₂ reduction planting model was calculated at a maximum rate of 70.16kg-CO₂/year in reduced atmospheric carbon. The amount of CO₂ reduction by shading effect of planting trees was larger than fixing effect. These result showed that necessities to investigate the planting design for the shading effect, as measures of the global warming in the future.

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In order to evaluate green shade effects of pergola for thermal environment of car parks quantitatively, temperatures of air and ground surface, in and out side of car bodies, as well as direct insolation, and wind velocity were measured both in sunny and shaded sides. Dashboard's temperature reached over 70 °C in sunny side, when it remained over 10 °C of air temperatures in shaded side. Differences between ground surface temperature of sunny and shaded side were strongly affected by ratio of pergolas'roof cover ratio. Green shade effects of pergola considered enough for improving thermal environment of car parks. Also, idling stop to control carbon dioxide emission were expected by setting pergola above car parks.

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To clarify the preferable green roof design in Kyoto City we made landscape evaluation and the eye mark recorder experiment. Sixteen images were made by combining four spectacle pictures that were taken from the rooftops in the Kyoto city with four green roof pictures. It was shown that the evaluation values improved with the increasing of amount of the planted area if the style of the green roof was changed by the same background. In addition, it was also shown that the green roof like Japanese style garden obtained the high appraisal. Result of the eye movement measurement using the eye mark recorder suggested that the testees tended to search for artificial things by increasing the amounts of planted area on the compound image. From these results, it is considered that the Japanese style garden is more suitable for green roofs for buildings in Kyoto City where old traditional spectacle are left now.

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The human response was verified when in contact with turf grass mowed at three different heights by investigating human physiological and psychological indices. Zoysia matrella Merr. mowed at 20mm, 40mm, and 70mm in height were prepared and 13 volunteers (seven males and six females; 20-24 years old) participated in the experiment. Cerebral blood flow volume using NIRS, heart rate, impression evaluation using the SD method, and mood evaluation using POMS were surveyed. In the SD results, turf grass mowed at 70mm had the highest score in Naturalness and Friendliness. Any notable differences were not found among the three turf grasses in POMS. Cerebral blood flow volume decreased with all turf grasses, and the most significant decrease was found in that having the 70mm height.

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