To grasp the change of vegetation around forest roads without revegetation technique, we conducted vegetation analysis considering the period after construction and conditions of location. Experimental design was 3-way layout involving 3 factors, in which the period after construction (11 years or 36 years), openness of vegetation above the road (open or closed), and method of sloping (cutting or filling) were considered. Two sites for each combinations, 16 sites in total, were investigated in 2×5m quadrate. Field survey was conducted in Terasawayama Research Forest, Shinshu University, Japan. Number of arboreal species, mainly sybzoochore shrub, was more in 36-year after construction than in 11-year. Number of herbaceous species and total coverage seemed to increase in the plots where vegetation was open above the road, but we found that the vegetation around forest road was generally sparse. Then, we surveyed wild birds by modified belt-transect survey, which openness of vegetation, special structure and movement of birds were added, so that we might examine the viewpoint of wild bird community as a method evaluating the vegetation around forest roads. In addition to Terasawayama, other 5 sites form the banks of large liver to semi-alpine forests were also surveyed to compare different forest environment. Number of wild bird species had significant relations with openness of vegetation, which the optimal openness for birds varied among sites. Birds showing conspicuous movement during observation were limited almost to the common resident species, and the movements were counted more in the sites where bird species did not determined by the existence of trees or existence of herbs.

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Eco-mixed seeding and planting method are used to restore woodlands to a condition approximating their natural state, by taking advantage of the mechanism whereby forests regenerate places where trees have been uprooted by wind. When trees are uprooted, areas where root systems had spread become de-nuded. The seeds of many tree species that naturally spread into the denuded areas at about the same time germinate and start growing. The trees that grow there form a woodland of pioneer trees, which later undergoes a transition to that of climax trees. The eco-mixed seeding and planting method aims to reproduce this process. This method was initially developed in 1991 to regenerate riparian trees, and the present method was established in 1995. For the last ten years, it has been undergoing trials. The method involves a comprehensive system that covers the setting of objectives, seed collecting, seedling cultivation and planting, record tracking, follow-up survey, and evaluation. During those ten years in Hokkaido, 100,000 trees of 70 species have been planted at about 100 sites including riverbanks, embankments, dams, and road slopes. Data are continuously gathered on these trees. These data show that, as initially aimed, there has been rapid restoration of woodland by pioneer trees and gradual transition from such woodland to that of climax tree species.

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Changes of microbiological characteristics during the revegetation of two naked hill slopes were examined as an index for the recovery of natural environment. The number of bacteria increased and the number of fungi decreased with the lapse of years during the revegetation of the slopes, while there was no clear tendency in the number of actinomycetes. Each ratio among them, i.e., bacteria/fungi (B/F), actinomycetes/fungi (A/F), and bacteria/actinomycetes (B/A), showed a clear tendency of exponential decreases with time. The correlation between the ratios with the physical and chemical properties of the soils was also observed. Among these ratios, B/F reflected the changes of the chemical properties of the soils during the revegetation of the slopes most clearly. Although some kinds of restriction are known to exist, dilution-plate method for the evaluation of soil microorganisms was shown to be effective in this experiment, as it was useful for obtaining the index of soil development on the slopes.

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Wall greening is attracting increased attention as an effective method for mitigating the environmental loads in urban areas and thus preventing the heat island phenomenon and global warming. The purpose of this study is to obtain the fundamental data needed for the examination of the direction of technology development for the future promotion of wall greening in urban areas and the object and range to be mainly grappled with in the field of research and development. The investigation was conducted by a questionnaire survey on 119 private companies which are grappling with the greening, development and utilization of rooftop spaces, in order to grasp the consciousness of those companies and their technical staffs about the market of wall greening, and the possibility of propagation, and sort out the technological tasks. The survey revealed that (1) the companies expect the wall greening market to expand, (2) the technical staffs recognize that the important thing in the technology development for wall greening is the quantification of environmental improvement effects the reduction of the costs of constructing and maintaining the green walls, and (3) the technical staffs also recognize the differ of the sites on which wall greening can be applied and the possibility of propagation among 6 types of wall greening ( 1) utilization of natural ground as the base of plants, 2) utilization of flames for support as well as natural ground base, 3) utilization of planters on each story, 4) utilization of planters with flames for support on each story, 5) installation of greening panels, 6)utilization of concrete blocks for greening).

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Ground beetle fauna were investigated using pitfall traps at sites in a suburban coppice forest where management, such as weeding and litter cleaning, was conducted every year, and at sites that had been abandoned for a short time (since 1995) or for a long time (since 1975). The numbers of families, species, and individuals were greatest at a site that had been abandoned for a long time. The rate of Silphidae individuals was highest at each kind of site, and was higher at a site abandoned for a long time than at managed sites. The number of Eusilpha japonica, a dominant species, positively correlated with the number of years abandoned. There were positive correlations between the number of Silphidae and Curculionidae individuals, and litter amount and EC. Negative correlations existed between the total number of individuals and soil hardness and water content, and between the number of Nitidulidae individuals and relative photon flux density and soil temperature. Therefore, the reactions of ground beetles to changes of floor environment with abandoned years seemed to differ for each insect group. Detrended correspondence analysis revealed that the community structures of ground beetles at managed sites and at a site abandoned for a short time were similar, but differed from that at a site abandoned for a long time. Peculiar species groups of ground beetles were recorded in order of the number of years abandoned. Consequently, to conserve the diversity of ground beetles, mosaic forestation using forests of various floor managements is desirable.

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This paper investigates the results approximately 9 years after the application of a method based on spraying of thick growth media in Karatsu City, Saga Prefecture. We compared communities of Chinese-grown Indigofera spp. (CHA-I) and mixed communities of these species combined with evergreen broad-leaved trees (EBLT, using Ligustrum obtusifolium Sieb. et Zucc., Rhaphiolepis umbellata Makino, Camellia japonica L., and Camellia sasanqua Thunb.) on cut slopes. We found that: (1) The EBLT communities can protect slope surfaces as well as forest-floor vegetation even if the canopy is initially completely covered by CHA-I. (2) The density and basal area of CHA-I tended to decline, which suggests that plant succession is occurring towards EBLT communities. (3) The EBLT community, serving as forest-floor vegetation, is effective at keeping green vegetation on the slopes during the CHA-I deciduous season, except when using L. obtusifolium as a semi-EBLT. CHA-I has an average height growth of more than 3 m compared with a height of 0.5-1.0 m Japanese-grown Indigofera pseudo-tinctoria Matsum., even though CHA-I is showing a tendency towards delayed plant succession from a pioneer community towards an EBLT community. Therefore, CHA-I should be considered in revegetation work. The effects of mixed CHA-I and EBLT seedings suggest that it would also be possible to introduce Lespedeza bicolor var. japonica Nakai. and Amorpha fruticosa L. as other leguminous shrubs. This technique can regard as one of the effective slope revegetation technique to solve easily the ecological problems of leguminous shrub communities in terms of the decline of forest-floor vegetation, monospecific forestize, stagnation of plant community succession and landscape problem in the deciduous season.

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We studied 1) the relationships of species richness of herbaceous plants to environmental variables such as area and shape, or to artificial disturbances and 2) species distribution pattern and characteristics of the species that are likely to depart from nested distribution pattern (species recorded at a lower-level subset are entirely embedded within an upper-level subset) at 14 precincts of shrines (non-forest area with unpaved surface) in Kyoto city, for acquiring basic information about conservation of biodiversity at urban area. Consequently, there was a strong relationship between species richness and area. Alien species richness significantly had negative partial correlation with the percentage of tramped area and positive partial correlation with the percentage of clearing management area. Since species distribution was significantly nested, conservation from the upper-level subsets was basically a better option. However, perennials and the species recorded at one precinct tended to depart from nested pattern. Some red-listed species were recorded at the lower-level subsets. Conserving several precincts including the lower-level ones was deemed necessary.

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[in Japanese]

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