Our human race has engaged to develop various new technologies for revising Life Quality based on the assumption of limitless environmental recovery ability of the earth since Industrial Revolution. As the results, certainly we could realize the high quality of Life, but our activities including economical, industrial, political and ethical matters have been now facing to very complicated and difficult environmental problems for realizing our sustainability. As one of typical examples, many construction concepts of Eco-town have been proposed and realized by the local governments et al. But the effectiveness evaluation scheme for realizing the sustainability about Eco-towns seems not yet be established until now. On the other hand, the concept of Ecological Footprint was proposed in 1990 by Rees. W. E. of British Colombia University, Canada. Effectiveness evaluations using this method about already constructed Eco-towns and just designing Eco-towns seems better to be conducted for revising their effectiveness.

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For realizing the recycling society, the large-scale and centralized recycling system is mainly studied. However, taking account of handling and transportation of materials to be recycled, the small-scale and decentralized recycling system could be more viable to save the resources. We have advanced the assessment on the self-sustainable apartment complex, so-called ECOTOWN, which is typically small-scale recycling society. It has been clarified that the operation of the self-sustainable apartment is practical as a whole by the introduction of the technologies of better thermal insulation building materials, energy-saving electric appliances, energy and cost saving life style, the use of the natural energy resources and the waste to energy facility, etc. This article provides the further studies on more practical operation of ECOTOWN from the view point of mass balance such as water, food, wastes and the like in addition to the energy balance which has already been studied.

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The background, origin, approved areas, and changes of Eco-town projects in Japan are explained. As Eco-town projects are various types of projects, to categorize Eco-town projects into a few types is useful for the local governments and companies, and also, East Asian Counties who try to develop their own Eco-town project. In last, some future challenges of Eco-town projects are described.

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A decade has passed after the Fukuoka University Institute for Recycling and Environmental Control Systems (FIRECS) was established at Kitakyushu Eco-town. In this text, details in establishment of the FIRECS are described at first, and what contribution has been made for the development of the Eco-town is described in the next. An ultimate target of Eco-town is to concentrate the professionals of the field of environmental science and technology to make develop the eco-technology, and it makes revive the eco-business. Based on the resources of the town, the young persons who grew up will start to construct a sustainable community. Academic support to design such a sustainable community is considered to be one of the roles of the university.

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World population is rapidly increasing, while the current food production cannot meet the need of the exponentially growing population. Accordingly, we are planning to develop a new food resource system by photosynthetically culturing a microalga Euglena gracilis. Moreover, it is aimed to reduce the excessive CO₂ in the atmosphere by making use of culturing Euglena. As a fundamental study on this new food resource system, this paper investigated the effect of light quality and CO₂ concentration on photosynthetic growth of Euglena. Light emitting diodes (LEDs) were used as red and blue light sources to examine the effect of light quality. On the air condition (with 0.04 % CO₂), red and blue (PPF ratio = 9:1) LEDs showed the best effect on the growth of Euglena, while blue LEDs the worst. On the condition of high CO₂ (with 10 % CO₂), no significant difference was found in the growth of Euglena among all of the light quality treatments. Chlorophyll content and Chlorophyll a/b ratio may account for these results. On the air condition with blue LEDs, energy level of photons is higher than those in other light quality treatments. The synthetic amount of protein of photosystem II (PS II) is more than the destructive one, and consequently the amount of protein in Chlorophyll b increased. Thus Chlorophyll a/b ratio decreased with the increase of Chlorophyll b. As a result, photosynthetic growth of Euglena decreased due to the decrease of photosynthetic activity. In contrast, on the condition of high CO₂, since Euglena does not have the mechanism of CO₂ concentration, much CO₂ available for reduction presented in cells. Thus by increasing the CO₂ reduction and photosynthetic activity, Euglena in high CO₂ grew better than in the air.

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It has been reported that Euglena contained ascorbic acid (AsA), α-tocopherol (α-toc) and β-carotene (β-car) asantioxidant vitamins. These vitamins contribute to the available antioxidant and nutritional resources in human and animal bodies. In the present study, we investigated the effects of light quality and CO₂ concentration (0.04 % and 10 %) on the production of these vitamins, and compared the vitamin contents in Euglena with those in other food sources to verify the availability of Euglena as an antioxidant vitamin source. Under the CO₂ concentration of 0.04 %, vitamin contents in Euglena cultured in blue light were AsA 746 μg 10⁹ cells^-1, α-toc 704 μg 10⁹ cells^-1, β-car 513 μg 10⁹ cells^-1, respectivery, higher than those in other LED light conditions. Whereas under the CO₂ concentration of 10 %, vitamin contents in Euglena cultured in blue light were AsA 231 μg 10⁹ cells^-1, α-toc 221 μg 10⁹ cells^-1, β-car 208 μg 10⁹ cells^-1, respectivery, lower than those in ordinary air conditions (with 0.04 % CO₂). No significant differences in vitamin contents were found between the four light quality treatments under the CO₂ concentration of 10 %. In addition, vitamin contents in Euglena cultured in blue light under the CO₂ concentration of 0.04 % were also compared with those in other foods that are more popularly used as vitamin sources. It was concluded that Euglena would be good vitamin source when they are cultured in blue light under the ordinary air condition (with CO₂ concentration of 0.04 %).

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Monoterpenes are highly reactive biogenic volatile organic compounds (BVOCs) with O₃, OH radical, and NO₃ radical. Although these reactions may occur in the aerial space under tree canopies, only a few studies about monoterpene behavior under the canopy are available. In the present study, concentration profiles of six monoterpenes (α-pinene, myrcene, β-pinene, sabinene, limonene and β-phellandrene) were measured in a Japanese red pine forest in June, July and August, 2002. Their concentrations were usually low in the daytime, but high in the nighttime. Monoterpenes were stored under the canopy during nighttime and the amount as a total of the six monoterpenes was calculated as more than 700 nmol m^-2. The variations of their concentration ratios were also observed. The concentration ratio of myrcene to β-pinene was usually low in nighttime and high in daytime. It ranged from 0.27 to 2.28. Correlations between the ratio of myrcene/β-pinene and O₃ concentration or NO₃ radical production rate were 0.78 or 0.54, respectively. These results suggested the possibility that the low concentration ratio in the nighttime was due to decomposing of monoterpenes during the storage period under the canopy. The stored monoterpenes would influence the next-morning fluxes since these fluxes include stored and decomposed monoterpenes during the nighttime. The evaluation of the amounts of stored and decomposed monoterpenes will be important when measuring monoterpene fluxes or determining monoterpene contributions to aerosol formation in the forests.

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Moss plants have been generated much attention as a new greening material in recent years because of their lightweight, ease of maintenance, high tolerance to environmental stresses and high transpiration ability. In order to produce moss plant for greening efficiently, the growing conditions should be controlled to achieve its optimum growth. For the optimum growth, the optimal conditions for photosynthesis must be achieved, hence establishment of the appropriate method to assess the photosynthetic functions of moss plants have been required. In this study, we analyzed the photosynthetic functions of Hypnum plumaeforme Wilson by measuring photosynthetic light response curve using self-developed gas exchange system and capturing chlorophyll fluorescence parameter images using self-produced chlorophyll fluorescence imaging system. As a result, low light compensation point and low respiration rate were observed in the photosynthetic light response curve. The result showed that the characteristics of gas exchange of the Hypnum plumaeforme were acclimated to the low light condition under the plant canopy. Furthermore, heterogeneous distribution of photosynthetic abilities was observed in the chlorophyll fluorescence parameter images. At the tip sites of the individual moss bodies, the activities of photosynthetic electron transport and heat dissipation of excessive light energy were lower than the other sites. These results suggested that the tip sites of Hypnum plumaeforme are relatively less tolerant to high light stress.

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