Recently urban heat island phenomenon has become a serious object of public concern. This paper aims to clarify the cooling potential of urban greenery spaces in summer time. At first, it shows that greenery space and anthropogenic heat emission have a great effect on the temperature in downtown areas from the various data collected from 27 observation points in Minato-Ku, Tokyo. Then, it clarifies the cooling potential of greenery spaces. From the regression analysis, it can be said that the cooling influence by greenery spaces of 22,500 square meters is equivalent to the heating influence by the anthropogenic heat released from two offices of the average size in Minato-Ku, having a total floor area of about 211,726 square meters. Furthermore, the cooling potential of a greenery space of 22,500 square meters during July to September can be expected to reduce about 236 times as much quantity of the carbon dioxide as the same greenery space absorb for one year. In conclusion, greenery spaces in urban downtown areas have the function of air-conditioning given by nature.

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Effects of annual prescribed burning on Viola raddeana, an endangered wetland herb species were examined. We conducted burned site and not burned site in November 2006 in habitat of V. raddeana. Densities of seedlings and over-wintered individuals were recorded and sizes of over-wintered individual were measured. Soil water contents, temperatures of near ground surface and rPPFD were also compared between the two sites. Seedling densities in burned site were higher than not burned site both in 2007 and 2008. Seedling density significantly increased from 2007 to 2008 in burned site. Over-wintered individual densities in burned site were larger than not burned site both in 2007 and 2008. Therefore, annual prescribed burning was effective for seedlings of Viola raddeana. On the other hand, the sizes of over-wintered individual in burned site were lower than those in not burned site. Continuous burning may reduce growth rates of individuals.

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The objective of this paper is to clarify the way of rock arrangement of Soeki Katsumoto (1810-1889), also called Donketsu, a garden designer of Ohmi region. Firstly, the rock gardens that he had drawn in his garden-making treatise were analyzed. The results were as follows. 1) Verticality had been expressed through the specific proportions and the placement of the main rocks. 2) The secondary rocks with their shapes horizontal had made up contrast with the main figures' verticality. Then, the rocks of his three built works were examined. Expression of verticality was recognized in two gardens, but contrast with horizontal rocks was made up in one case.

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The ratio of vertical green coverage has generally been used in landscape evaluations. Until now, measurements of this ratio were calculated manually by researchers. However, it was difficult to obtain accurate data by this method due to the excessive time and effort required in the measurements and human error. This paper aims to clarify a new method of measuring the ratio of vertical green coverage using leaf colors. First, the author focused on leaf colors (in particular, chlorophyll) and specified the region of those colors in the CIE1976u’v’ chromaticity diagram in a sample survey of urban parks. Using the minimum value and maximum values from the CIE1976u’v’ chromaticity values of the leaf colors in photographs taken at the same points, the region for calculation was decided as an inside ellipse formed by the u’ axis (0.14 – 0.23) and v’ axis (0.49 – 0.56), excluding the area of gray in the field of the categorical color. The effectiveness of the approach using this region was validated in a 1-year field test. The results of a correlation analysis of 23 samples from these image data for the values calculated by this method and the values obtained manually showed a very high correlation coefficient (0.981). In conclusion, the use of this measurement method will enable easy, objective, correct, and useful calculation of the ratio of vertical green coverage, reflecting the differences of tree species and seasons.

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To clarify that the removal of the dominant alien plant in alien plant species-rich area incur the other alien species occupation without early restoration of the native plant communities, we investigated species composition, coverage, the number of species per quadrate, and their transition during the first 75 days after the single-cutting in summer on the invasive alien plant Sicyos angulatus community, in Inagawa River, Hyogo Prefecture. As results, in the cutting experiment, we found that during the transition from 0 to 75 days after the single cutting, trend toward an increase in the number of species per quadrate is common to alien and native species, whereas the coverage of alien species increased threefold more than that of native species. The cutting experiment replaces the dominant species in the community from Sicyos angulatus to the alien plant Brassica juncea in the short term in the next spring. These results indicate that the elimination of the dominant alien plant in alien plant species-rich area has a temporary positive impact on the species richness of native plants in the community but cause the other alien species to dominate the community.

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We made a landscape evaluation experiment by the semantic differential method to clarify the green roof design which is preferable for the Chinese of future Chinese cities. Ten composite pictures were made combining a picture of a modern or a traditional Chinese city landscape that were taken from roof tops of buildings in Chinese cities with a bare roof or four green roof pictures. In the profile analysis, the psychological evaluation values of the images made with a bare-roof resulted in lowest by most of evaluation subjects. The style of the green roof highly affected the evaluation. For example, Chinese styled-roof garden got highest scores by 10 subjects (out of 22 subjects) in combination with the traditional modern city landscape, but only three subjects with the modern. With the factor analysis, the following five evaluation factors were understood as landscape evaluation structures of green roofs in the background of Chinese city landscapes: comfortableness, style and form, Green quality and quantity, openness and harmony. Using the factor score, the effect of various landscape elements on the psychological evaluation of the green roof was examined. As a result, the psychological evaluation rate rose as the green regard rate increased (r = 0.889, p = 0.001) and as the building rate decreased.

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This paper examines from literature the ways of understanding landscape and its experiences to make a typology of them as models. Using the published works of landscape studies and essays as materials, this paper reviews and studies background theories, definitions of the subject, concepts of landscape, and formulations of man-environment relationships. As the result, four models of landscape are extracted and shown: 1. a landscape discovery model based on modern theory which deals with landscapes as compositions established by individuals who withdraw from environment; 2. a landscape reading model based on post-structuralism which takes landscape as text and its experience as a creative process of deconstructive reading; 3. a landscape emergence model based on phenomenology which deals with landscape experience as the beginning to a new horizon, and 4. a landscape-in-silence model which focuses on the state of non-conscious experience of environment that involves the embodiment of environment. Discussions are made to specify the scope of each model, and finally, these four models are plainly listed in a table.

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The purpose of this study is to clear the relationship between the programs of nature conservation work and the relaxation effect which were planned by city residents and a local administration in a secondary forest in autumn and winter. As a result using POMS (Profile of Mood States), the following became clear. 1)Stress of participants are reduced and motivations of them rises adversely by performing nature conservation work, in spite of the participants were didnt have any stress before conservation works. 2)For a participant which has high score of stress and low score of motivation before, stress is easy to decrease, and motivations are easy to increase. 3)A person who has a little experience of participation can expect a relaxation effect by activity in autumn and winter. The nature conservation work that utilized nature in the Satochi-Satoyama of a city was effective in relaxing a participant, and the relations between programs of nature conservation work with the relaxation effect became clear.

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‘Collective intelligence’ is defined as groups of individuals doing things collectively that seem intelligent. Currently, many students have digital cameras or cell-phone cameras. Moreover, a good network environment is commonly available and it has become very easy to collect email photos. We aimed to analyze a landscape cognition using ‘collective intelligence’ to collect large number of photos taken of a target place by many students. A web-based system was developed to aggregate the collected photos. On this web system, each student used subjective criteria to put all of the collected photos into groups of ‘similar’ photos. A similarity matrix between the collected photos was measured to sum up each student's subjective perceptions of similarities. The configuration of photos (i.e. a landscape similarity map) was obtained by using MDS. The landscape similarity map was uploaded to the web. A landscape survey conducted by 22 students from the Tama farm of the University of Tokyo revealed three major landscape components of ‘buildings’, ‘farms’ and ‘roads’. Another landscape survey conducted by 29 students from the Hongo and Yayoi campuses of the University of Tokyo revealed four major components of ‘buildings’, a ‘pond’, a ‘mighty tree’ and ‘roads’.

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