A forestation experiment was conducted by revegetating cutting slope using the method of seedling placement and growth base spraying. The experiment planted 11 specie container seedlings in a 4 kind of fields consisting of a 2 kind growth base (organic thick growth base material and inorganic thick growth base material) and a 2 kind growth base with a 5cm and 10cm thickness on a 45degrees of cutting slope of soft rock. The probability of survival of a young tree 3 years 7 months after planting was over 70 % for 8 species, while withered and dead plants were substantial for 3 species. Dead plants were common in the inorganic thick growth base material. Withered and dead plant patterns varied for first year to second year. For most species, tree height tended to be much more vigorous in organic thick growth base. The results suggest that when using the method of seedling placement and growth base spraying for cutting slope forestation, design and execution compatible with species and growth base are crucial.

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When slow germination and growth plants were used in growth material spraying revegetation method, long term erosion tolerance of growth material is important factor. The purpose of this study was confirming the tolerance of sprayed growth material for revegetation. We measured erosion of sprayed growth material for three months after revegatated. Three types of experiment plots were set with wood boxes One was sprayed only growth material, and one was sprayed growth material which was mixed forest topsoil in 20%, and one was revegetated normal growth material spraying revegetation method used common revegetation seeds. We set the boxes in 63° and 45°. The plots used topsoil and revegetation seeds were covered by plants. Erosion thickness of growth material for three months was 0.55-1.16 cm in 63° plots and 0.15-0.70 in 45° plots. Erosion values were comparatively small and normal growth material spraying revegetation plots were the most eroded. In addition, we measured erosion tolerance for heavy rain (100 mm/h) used artificial rain machine. The maximum erosion thickness was 0.04cm and maximum weight of eroded growth material was 3.6g/m². These results confirmed that bare growth material and growth material even mixed topsoil in 20% had satisfactory tolerance for erosion in three months after revegetated.

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Knowing root system is basic but important information for care and transplantation of planted trees. However, only very limited methods such as excavation or washing out roots by high-pressured water have been used for root system investigation. The authors tried to develop a quite new non-destructive method to investigate tree root system, especially horizontal distribution of them, by using vibration. Impacts were given to Robinia pseudo-acacia's trunks by hammer and speed of vibration were measured and analyzed. Consequently, it became possible to estimate direction of main roots in a radius of 2.5m of target trees. Moreover, drawing estimated horizontal root existing area became possible by using Sufer8 and the performance of the estimation was between 59.8-73.6% including adjacent neighboring tree's roots and 51.7-70.0% excluding them.

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We investigated the effects of volcanic ash and gas (sulfur dioxide) on chemical properties of the mineral soil surface in Miyake Island. The pH(H₂O) values of mineral soil increased from 4.0-4.4 in 2004 to 4.3-4.8 in 2006. Calcium and sulfate ion were washed out from the volcanic ash by acid rain water, so the mineral soil were protected by buffer effect of the ash. Though the sulfur dioxide concentrations were high (0.2-0.5 ppm), the vegetation were fast restorated because of the thick ash sedimentation (upper 10 cm) in east and north area of the Oyama volcano.

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This study focused on changes in morphology and settlement process of vegetation at the sandy shore of Shonan. It was found that the vegetation area increased because damage from ocean waves decreased due to the increasing height of the sandy shore and shoreline advancement in the study area. In addition, we analyzed the relationship between vegetation and morphology by electivity index. The results showed that different species were present in locations with varying damage from ocean waves. Furthermore, it was found that dispersal of submerged seeds by sea currents was largely absent. As a result, it is considered important to take into account the influence of different patterns of ocean wave damage on coastal vegetation in artificial beach.

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The effect of river improvement works, including dam, revetment and groin construction, on seedling sites of Chosenia arbutifolia (Pall.) A. Skvorts, an endangered species, was investigated in the Satsunai and Tokachi River in Hokkaido. The peak, scale, and frequency of the river disturbance were greatly decreased due to the dam construction. Further, the area of seedling site for C. arbutifolia created by flood-like disturbance was also decreased. Numbers of C. arbutifolia seedlings, however, were observed at the revetment and groin sites. The study demonstrated that river improvement works, especially dam construction, would cause greater damage to seedling site for C. arbutifolia. In contrast, the works like revetment and groin construction would create the seedling site, and would perform important ecological functions, instead of natural disturbances.

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The distribution of the vulnerable plant species Ludwigia peploides ssp. Stipulaceacea was investigated at biyearly from 1998 to 2006, in the Kashio River, eastern Kanagawa. As a result, it was recorded approximately 25-55 local populations. Total cover size were 1,000-1,750 m² in each year and its averages was about 1,500 m² (N=5), that is, this species has grown roughly with stability for the investigation period. It was clarified that this species maintained the meta-population shifting position in the river while repeating the formation, the increase and decrease, and the disappearance of the local population by small number of large-scale populations and a lot of small-scale populations. When the relation between the growth size and the river structure of each section was analyzed, it was suggested that the width of the river and existence of the pier positively influence.

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Although Konbukuro-marsh on the Hokuso-tableland is located in urban area, there are valuable habitats of rare hygrophytes in Chiba Prefecture. The purpose of this study is the consideration of conservation measures for Malus Sieboldii Rehd. through the study of growth state in relation to environmental conditions. Malus Sieboldii bloomed over 150cm and high flower-set grade was observed under the canopy with higher gap ratio than 10%. Fruit-set rate was low. More than half of blooming trees was sterile. The fruit-set rate of 3/4 of blooming trees was less than 5%. Seedlings were few and those were established almost on bare soil without litter. In order to conserve Malus Sieboldii, it should be necessary to take measures, such as vegetation control and artificial disturbance to preserve the safe site of seedlings.

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In this study, we hypothesized that small-scaled gaps would facilitate the emergence of late successional species and that an abundance of understory vegetation would influence the gap responses of the forest floor vegetation, focusing on the regeneration dynamic within canopy gaps in planted, warm temperate forests. Two different sizes of canopy gaps were formed in two plantations with different understory abundances and the dynamics of the microenvironments and the forest floor vegetation were studied for 4 years pre- and post-gap. Based on our results, the first hypothesis was not supported, and the second hypothesis was supported.

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We investigated the dead forms of canopy trees and regeneration process in Tadasu-No-Mori Forest in Kyoto city. The types of dead canopy trees had little effect on establishment of seedlings. The dominant species in canopy layer, Aphananthe aspera, Celtis sinensis, Zelkova serrata and Cinnamomum camphora seedlings were classified into the same group by TWINSPAN. This result suggested that this 4 species had the similar regeneration niche. A. aspera, Z. serrata and C. camphora seedlings had low densities. In contrast, Trachycarpus fortunei and Quercus glauca seedlings had very high densities in forest floor. This indicated that Q. glauca would be the dominant species in canopy layer in the future.

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To clarify the fact that vertical movements of vegetation zone had occurred for twenty and several years, species composition of plant communities was surveyed on the artificial slopes along the mountain roads at the two periods. 18 species had moved upward for about twenty five years. Average annual temperature differences between the two periods 1951—1980 and 1971—2000 in research sites were in the range from -0.05 to 0.66 °C. This result indicated that the climate in study sites would had been warmer. There was the negative correlation between average annual temperature and score on axis 1 in correspondence analysis. This result assumed that regional temperature had much affect on the distribution of plant species in mountain area.

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Our interests are in detecting the spatial pattern of Phyllostachys nigra culms within growth stages-sprouts, current-year culms, and 5-year-old culms- and discussing the changes among them. The analysis used Ripley's univariate L(t) function. Change in the spatial pattern among growth stages was not observed in the intermediate and edge parts of bamboo forest where culms were less aggregated from early stage. In the interior, sprouts and current-year culms had clumped distribution at almost all distances in years with high annual culm production. Spatial pattern changes were observed from a clumped distribution of current-year culms into a less aggregated distribution of 5-year-old culms. We infer that the density is a determinant in forming the spatial pattern of culm stage of P. nigra v. henonis through competition in the stand with high density culms.

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The changes of soil nitrogen properties, nitrogen-use properties and the biomass of Pleioblastus chino Makino were studied for 3 years under the treatment of underlayer-mowing and litter-removal. Aboveground biomass of P. chino was decreased by treatments. Belowground biomass of P. chino was not affected by mowing, but reduced by litter-removal. Total nitrogen content of topsoil was slightly decreased under the treatments in the half-shade site under Zelkova serrata. Soil mineral nitrogen content was decreased by mowing, and more decreased by litter-removal. Although the nitrate reductase activity (NRA) of plants were not different among treatments, it changed due to soil nitrate content and light condition. As NRA was increased in winter without canopy cover, autumn harvesting should be effective on the control of P. chino.

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Ludwigia peploides ssp. Stipulacea is endangered aquatic plant, and grows locally at the Kashio River in Kanagawa Prefecture. However, the sandbar for the habitat of L. Stipulacea will be lost by riverbed excavation work started from 2006. Therefore, the transplantation of L. Stipulacea to alternative habitat has become serious problem. In this study, we experimented in transplantation by cutting method, using subterranean stems and terrestrial stems. As a result, the subterranean stems were corroded when they were buried into the soil that covered with water. Moreover, it was good for growth of the terrestrial stems to transplant to the place where the ground was always covered with water. From these results, in case of using subterranean stems, it was suggested that it is necessary to avoid an anaerobic environment. And in case of using the terrestrial stems, enough moisture is necessary for the growth.

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Remote sensing technique has been used for evaluation of vegetation distribution. NDVI (Normalized Difference Vegetation Index) is one of the most famous indexes, and the usefulness has been shown by a lot of papers. However, the value of NDVI is decided with several factors of vegetation, such as vitality, fraction, and the stage of the vegetation. So NDVI is not an appropriate index to evaluate detailed vegetation factors. In this paper, we discussed the method to evaluate vegetation vitality and fraction together with spectral reflectance data. It was shown that combining NDVI and VIgreen (normalized visible red and green reflectance) is possible to evaluate vegetation vitality and fraction.

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Using the rhizopods, the ecophysiological characteristics were compared among 6 tree species grown under 3 different water tables (40cm, 70cm and 90cm under soil surface), cuttings of Salix psammophila and S. matsudana planted for afforestasion in the Mu-us sandy land and seedlings of 4 native tree species in the Loess Plateau of China. The biomass and the root distribution of S. psammophila and S. matsudana changed markedly by different water table treatments whereas those of other 4 tree species showed very little changes. In the treatments, the growth of S. psammophila and S. matsudana were best under 70 cm and 40cm water table condition, respectively. The results suggest that growth in wet condition is fitter for S. matsudana than for S. psammophila and that both species are more sensitive to water table level than 4 tree species in the Loess Plateau.

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Recently, desertification progresses at Mu Us Desert in Inner Mongolia, vegetation is damaged by the over-use of nomads. This changed fixed dunes to semi-fixed and flux dunes. We investigated the distribution of A. squarrosum in the semi-fixed and flux dunes. The relative elevations from the ground-water level to A. squarrosum colony were researched. Moreover, the photosynthetic abilities of leaves growing at three layers (height 15cm, 30cm and 45cm) were measured.
As a result, A. squarrosum appeared between 107cm and 509cm in the relative elevation from the ground-water level. In addition, A. squarrosum was only present in a quadrat away from 327cm or more in the relative elevation from the ground-water level. Pmax in each individual leaf measured at the height of 15cm from the ground was 6.20μmolm^-2s^-1, at 30cm was 5.59μmolm^-2s^-1 and at 45cm was 2.18μmolm^-2s^-1. The Pmax at the upper leaf(45cm) is less than that of the lower leaf(15cm, 30cm).

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Leaf water relations obtained from P-V curves were compared among 3-year-old seedlings of six deciduous Quercus species (Q. mongolica, Q. dentata, Q. serrata, Q. crispula, Q. acutissima and Q. variabilis) distributed widely in eastern Asia, grown under different soil water conditions (control, pF2, pF3) for 2 weeks. Under well-waterd condition, Q. dentata showed the highest drought tolerance among the 6 species. In the condition of water deficiency, however, Q. variabillis showed the highest drought tolerance and Q. dentata followed. The drought tolerance of Q. serrata was the lowest under all three soil water conditions and Q. acutissima followed. That of Q. mongolica and Q. crispula was intermediate among the 6 species. As for the osmotic adjustment, Q. variabillis was supposed to have high ability but Q. dentata and Q. acutissima were supposed to have low ability.

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Trachelospermum plants climb by both aerial roots and twining stems, so, they are expected to be effective for covering walls and fences. In Japan, three Trachelospermum species which are named Teikakazura, Keteikakazura and Tokyochikuto are commercially distributed. However, as it is difficult to identify these species by consulting the references, they are confused when they are used as landscape plants. In this study, we tried the identification of these species by using floral organs as indexes. We investigated references describing these species and observed the floral organs that were collected from cultivated and native specimens. The results suggest that three Trachelospermum species can be identified using floral organs as indexes.

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We investigated the seed germination characteristics of Hydrangea petiolaris to use this species for greening. In laboratory experiments, optimum temperature for germination ranged from 25 °C to 30 °C and germination percentages were promoted by alternating temperatures under light condition. Highest germination percentage was 100 % at 30/20 °C. Seeds germinated less than 2 % below 20 °C. However, seeds given cold stratification germinated to 69 % even at 10 °C. Seeds stored in dry condition at 5 °C maintained their germinability for one year. Seeds need light to germinate irrespective of the temperature, cold stratification, or periods of dry storage. In field experiments, seeds sown between November and July of following year germinated to about 60 % until mid-August. When we grow the seedlings, seeds stored at 5 °C should be sown from late April to early May without soil covering.

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The healing effect of the lawn ground and the lavender field in the city park was verified according to a physiological and a psychological index. Blood pressure, pulse, and saliva amylase density were used for the physiological index, and the SD method was used as an impression evaluation for the psychological index. The blood pressure of the subject with high blood pressure fell when on the lawn and in the lavender field. However, the blood pressure of the subject with low blood pressure did not decreased further. On the lawn, the density of saliva amylase decreased. Moreover, the impression evaluation of "Settled down" and "Calm" was impressive on the lawn and the impressions of "It is interesting" and "It is pungent" were strong in the lavender field. When these results were synthesized, it was thought that the lawn could be evaluated as a place of "Rest", and the lavender field as a place of "Diversion of mind".

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In order to restore forests in abandoned clearcut areas covered with Gleichenia japonica Spr. in Owase region, Mie Prefecture, Japan, development of a low-cost method is required for preventing the damage caused by sika deer browsing on trees. Hence, I established study sites in these clearcut areas comprising spot weeding plots and planted hinoki (Chamaecyparis obtusa Endl.) trees. Next, I observed deer invasion patterns into the plots and the growth of the hinoki trees over a 2- or 3-year period. The invasion frequency decreased with an increase in slope steepness. With decreases in both the browsing damage levels in the first year and the top shoot browsing frequency in the second and third years, the tree height increased. Thus, I conclude that the method described in this study will be effective when applied to steep mountain slopes.

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In order to effective utilize the sewage sludge as the fertilizer; we clarified the characteristics of the incineration ashes of sewage sludge. Concentration of cadmium and lead contained in the incineration ashes material decreased dramatically with burnt up at temperature more than 700°C, as result of volatilization. Zinc and cupper contained in ashes of sewage sludge did not decreased after burnt up at temperature of 950°C but were transformed into in-soluble form by incineration treatments. Sequential fraction of heavy metals as affected by application of the incineration ashes material to soil was analyzed. A greenhouse experiment was conducted to compare the effect of application on the growth of grasses species. Application effect of phosphorus contained in the ashes was larger than that contained in the dried sludge cakes.

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HSI model of Periophthalmus modestus was produced on the data of intensive survey of the habitat in the river mouth mudflat of Arakawa river. The adaptability of the model was tested through the application to other mudflats in Tokyo Bay. The significant factor of habitat was selected as coverage of reed, ground elevation, oxidation-reduction potential, and silt-clay content of mud through recursive partitioning. The importance of the dissolved oxygen content of tidewater and the strength of wave was recognized after the application of the model to other mudflats. HSI model plays its own role through the habitat and temporal comparison. Modeling should need the reference data of some habitats for improving different problem.

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In this study, the effective recycling use of the Heat Compressed Crushed recycled EPS (HCCE) is discussed as a material of rooftop gardening. Effectiveness of the geo-structure with the HCCE and the volcanic ash clayey soils for the geo-materials of the rooftop gardening is evaluated in terms of adjustment to water retentivity, the water permeability, and planting by the experiment. According to the experimental results, it is concluded that the best mixture ratio of HCCE is about 40%. In the same mixture ratio totally, the geo-structure that divides into the water retentivity layer and the water penetration layer is more suitable for geo-materials of rooftop gardening, comparing that consists of the mixture of HCCE with the volcanic ash clayey soils.

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Soil medium for plant revegetation in city area has been surrounded with concrete structures. Growth of plants was concerned shifting from acid soil to alkali soil by addition of alkali material from concrete. We assessed soil alkalization about surface soil at 41 points that near at paved concrete of Osaka Sakai city, and at 8 points in the mountainous regions. The pH of soil was measured. The soil alkalization was slightly occurred in urban area compared with the mountainous regions. Soil pH has been kept in pH8.6 or less. Therefore, we considered that the soil alkalization might not be serious for revegetation in the present situation.

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The thermal environment measurement and the subjective experiment were made at 3 places (on the lawn, on the asphalt-paved path, under the wisteria pergola) on a green roof to clarify the physical and psychological quantity of the roof. Consequently, it was shown that the form of greening effect physical and psychology quantity except for winter. In summer, temperature and glove temperature under the pergola were lower than those on other two places and the test subjects also declared that it was cooler under the pergola than on others. Comfort zone was simulated as an area within crossed points made by a second regression line and the neutral axis of air temperature or globe temperature respectively. The zone by the pergola was wider than by the lawn and the asphalt.

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To quantitatively understand the effects of building greening, which involves greening of the walls and roof tops and is attracting attention as a means of mitigating the heat island phenomenon in cities and improving the thermal environment, a computational fluid dynamics (CFD) analysis was conducted using an actual district as a model to numerically analyze the changes in temperature and humidity in the district by building greening. The analysis showed that greening of the ground surface, rooftop and walls reduced the air temperature in the middle of the district by up to about 4°C from the case without greening and increased the humidity by up to 16%. It was suggested that quantitative evaluation of the thermal environment improvement effect of building greening could be estimated using CFD for actual block.

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