It is observed that the lack of open spaces became a serious issue, which lead to the problem of disaster prevention in the urban areas of Japan . After The Great Hanshin Earthquake, it is realized the necessity of keeping safety places in residential environment in the form of open spaces in urban areas . Therefore, the aim of this study is to make some suggestions in order to improve the situation of open space from the viewpoint of disaster prevention in Tokyo region. In this study, first, the authors tried to evaluate the present situations of open spaces in both district and regional level using Geographical Information Systems (GIS). Then, the authors suggest the way to improve open spaces from the viewpoint of disaster prevention in Tokyo. The main results are as follows: (1) It is necessary to improve both of small open spaces and large open spaces in balance. (2) It is essential to improve open spaces in response to nighttime population and daytime population in each area.

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Mass and economic overall input-output balance was studied between paddy fields which is steady system and their environment. Concentration of pesticides and manures in paddy fields, usage of pesticides, working times, the crop yields and economic balances were investigated during April to October in 1996 in three farmhouses (A, B, C) in Hirosima prefecture. Behaviors of pretilachlor and benthiocarb in herbicides in paddy fields were analysed by gas chromatography. Maximum concentration of pretilachlor in paddy fields of farmhouses A and B were 99.6-201μg/l in one day after spraying and 119-461 μg/1 in 1-2 days after spraying, respectively. Maximum concentration of benthiocarb in paddy fields of farmhouse B was 7.48.113 μg/l in 5-8 days after spraying. Pretilachlor in paddy fields of farmhouses A and B was detected until 22-28 days after spraying and 11-24 days after spraying, respectively. Benthiocarb in paddy fields of farmhouse B was detected until 31 days after spraying. pretilachlor outflow through drain and its rate to total sprayed pretilachlor were 1110 mg, 1.09% and 1043 mg, 0.77% respectively, in two paddy fields of farmhouse A. Since some pesticides (one is supposed to be benthiocarb) were detected in paddy fields of farmhouse C which does not use pesticides at all, a contamination of pesticides from surrounding p addy fields was observed. Amount of sprayed pesticides to standard usage was appropriate for both farmhouses A and B. Working time per paddy fields area was larger for farmhouse A than B except spraying manures. Working time of farmhouse C was much larger than those of A and B. Main expences of farmhouses A, B and C were manures&soil improvement, pesticides and ducks which eat insects and grass, respectively. Since ratios of income to expenses for farmhouses A, B and C were 8.6, 9.5 and 31, larger working time of farmhouse C was conpensated by larger incomes.

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The annual precipitation(P), evapotranspiration(Ep) and runoff(R=P-Ep) averaged for 5 years from 1990 to 1994 in the Iwaki River basin were estimated as 3704, 1403 and 2301×10⁶m³, respectively. The annual utilizations of water for rice cultivation, human life and industries were 736, 46, and 14 x 10⁶m³, respectively. Because of the heavy snowfall and the limited rainfall in spring and its large increase from summer to autumn, the runoff is large and constant in winter and then significantly decreases from March and reaches nearly zero in May and June, then increases again from July. The actual flow of the river, which is affected by the rapid thaw from the mountainous region in early spring and by the discharge from the dams according to the rice cultivation, greatly increases from February and reaches its maximum in April and on the contrary decreases significantly and reaches its minimum in May and June, while it increases again from July. The utilization of water for the rice cultivation begins from April, reaches its maximum in May and slowly decreases till August. The actual flow of the river coincides with the utilization of agricultural water in May, while in June it is only half and again becomes similar to the utilization of agricultural water at during July and August. These results indicate that the utilization of the runoff water for the rice cultivation is highly efficient. The environmental pollutants in the drained water which are born from fertilizers and agricultural chemicals utilized for the rice fields are concentrated and scarcely diluted when the water is returned again to the river. In conclusion, the intensive utilization of the runoff water for the rice cultivation greatly lowers the level of water flowing in the middle of the river and results in degradation of the natural environment in this river basin.

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The objective of this project is to estimate the health effect benefits expected in the year 2007 with alternative National Ambient Air Quality Standards (NAAQSs) for ozone in five urban cities in the eastern United States. The alternative standards identified were 0.12 ppm for 1 hour allowing 1 exceedance (old standard) and 0.08 ppm for 8 hours allowing 5 exceedances per year (new standard). This project selected cough and pain upon deep inspiration as the health endpoints. For each endpoint, health benefits were estimated by multiplying the total number of days of reduction in symptoms by the willing to pay (WTP) for a day of reduction. The WTP estimates were taken from existing studies using the metaanalysis as well as the contingent valuation method. The following results were obtained: the benefits will be higher in the cities where population estimate is large and the baseline ozone concentration is high; the estimates for health benefits show a large range depending on the combination of estimates for WTP and health improvement; and 8 hour standard will bring about larger benefits than the old standard. These results indicate that improvements in benefit valuation and more research on uncertainties are needed.

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The aim of this paper is to analyze the accuracy of estimation value of CO₂ emission derived from the I-O analysis. The paper utilizes the international I-O table for the consideration. In the estimation of the value of CO₂emission, two methods are utilized in the analysis up to now. This paper considers the accuracy of 4 estimation methods, which are 2 known methods and new 2 methods. The paper shows the accuracy with the root square error between the standard value and the estimated value. From the analysis, this paper shows that the estimated value derived from (I-A)^-1? F estimation method is the best in general.

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Excess heavy metals are highly toxic. Different organisms appear to have evolved different mechanisms for the detoxification of heavy metals in excess. In response to excessive uptake of heavy metals, plants and certain fungi produce metal-binding peptides that have the general structure (γ-Glutamyl-cysteinyl) n-Glycine, (γ-EC)_nG, with n = 2 to 11. Cadmium incorporated into the cell is detoxified by (γ-EC)nG. The idea of using some hyperaccumulative and hypertolerant plants to remove excessive soil metals, phytoremediation, has increasingly been examined. In this study, we characterized the enzyme responsible for (γ-EC)nG synthesis in rice root. Optimum pH of the enzyme is 8.5 and incubation period and GSH concentration optima are 2 h and 10 mM, respectively. The (γ-EC)_nG synthesis activity increased with Cd and Zn addition. Because the specific inhibitor of carboxypeptidase inhibited (γ-EC)_nG synthesis activity, it assumed that at least one of the (γ-EC)_nGsynthase in the rice root may be carboxypeptidase.

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