The urban heat island phenomenon in the Tokyo metropolitan area was simulated using the Colorado State University Mesoscale Model. For a realistic simulation of the urban heat island phenomenon, fractional vegetation cover estimated from satellite remote sensing data has been incorporated into the meteorological model, thereby effectively improving the surface boundary conditions. Comparison of the simulation results with actual data, received from a ground-monitoring network, confirmed that the simulation accuracy was improved by applying fractional vegetation cover data . The effect of vegetation in mitigating the heat island phenomenon was evaluated by comparing the simulation results between actual vegetation condition case with a novegetation case. The comparison showed that adequate vegetation reduced the typical summer daytime air temperature in the Tokyo metropolitan area by 1.5 °C. It was also confirmed that this cooling effect by vegetation was far less in winter than in summer.

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In this paper, economic valuation (financial and economic analysis) of Family sized Biogas Plant (FBGP) in case of Nepal is carried out, aiming at contributing to an appropriate policy measures for sustainable development of FBGP. As a result, it is showed that (1) FBGP is a good facility, of which cost performance is high, (2) slurry utilization as a fertilizer is indispensable in order to maximize benefit of investment, (3) external benefit is less than 10 % of total benefit and also less than actual government subsidy, (4) value of forest as sink of carbon dioxide occupies more than 90 % of external benefit. Based on the result and analysis of a present subsidy scheme, it is recommended that (1) a subsidy should be set according to external benefit, (2) a large size FBGP (community sized plant) should be promoted, (3) a mechanism which solve unfairness among areas and income classes should be incorporated in a subsidy scheme, (4) while gradually reducing a subsidy for an initial cost of construction, a financin system which enable future investors (farmers) to gain a loan with a discounted interest rate should be established.

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In this survey the economic value of road traffic noise was examined by Contingent Valuation Method (CVM) and Conjoint Analysis that is one of environmental valuation methods. In the CVM experiment, 4 conditions were prepared which were WTP _10db (65dB to 55dB), WTP _20db (75dB to 55dB), WTA _10db (55dB to 65dB) and WTA ₂₀ (55dB and 75dB). The median values of WTP _10db, WTP_20db, WTA_10db and WTA _10db were 1, 923, 2, 974, 8, 477 and 9, 056 (/month-person), respectively. In conjoint analysis, 3 conditions were prepared; CAsoUnd (presented sound, biased), CA_langnageA (language, biased), CA_langnageB (language, not biased). 16 kinds of profile of one-room apartment house were prepared which consist of 5 attributes and 3 levels based on orthogonal design. Attributes were rent, space, accessibility, newness and noise. Using these profiles, an experiment of paired comparison was conducted. The result of MWTP showed that CA_sound, CA_langnageA and CA_langnageB were 1, 925, 1, 514, and 1, 362 (-month-person). And it is found from this paper that first; in CVM survey, WTA/WTP is 1.53-4.40, second; in the survey of conjoint analysis, the way of explanation of noise situation and prejudice about the survey affect estimated values, third; WTP_eonjoint/WTPCVM is 1.60-12.9.

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It has been noticed that dissolved organic carbon (DOC) in throughfall and stemflow is possibly significant input for the carbon cycle in forest ecosystems. The purpose of this study is to estimate annual DOC flux of throughfall and stemflow by combining data from the field measurement with the calculation from multiple-regression analysis using meteorological factors, then to compare results to previous reports. Weighted average concentrations of DOC in throughfall and stemflow were 8.0 and 19.8 mgC 1-1 for Quercus serrata, 15.1 and 37.4 mgC 1-1 for Pinus densiflora, respectively. DOC concentrations were regressed by the global solar radiation for throughfall and stemflow of Quercus serrata and stemflow of Pinus densiflora, while it was predicted by the temperature and the duration of fine hours for throughfall of Pinus densiflora. Those results supposed DOC concentration of throughfall and stemflow were affected by the factor relating to physiology of trees. The annual DOC flux of throughfall and stemflow were estimated at 142 and 6.7 kgC ha-1 yr for Quercus serrata, 322 and 12.4 kgC ha yr-1 for Pinus densiflora. Comparing our results with previous reports, DOC flux for hardwoods correlate with precipitation and that of Pinus densiflora was larger than other coniferous species.

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Almost half of CO2 generation due to human activity is directly or indirectly derived from household consumption. It is useful to make clear distinction among the generations caused by various types of consumers, to formulate an effective policy for reduction in total greenhouse-gas generation. The study calculated household expenditures of various types of families based on the family income and expenditure survey published by the Statistic Bureau of Japan. Then they are connected with CO2 generation intensities corresponding to 87 kinds of household consumptions, so called the embodied environmental burden intensities, from the Japanese I-O table in 1995, in order to estimate the amounts of CO2 generationinduced by consumption of the families. The result indicated that a household with higher income generates more CO2, but that a ratio of the generated amount to income becomes smaller with the income increased. A household of aged people generates more CO2 by heating and lighting, but its generation accompanied by gasoline consumption is less than a household of younger people. A household of a young man alone generates considerably large amount of CO2 by gasoline consumption. For a household of more than two people, the gasoline-derived CO2 generation varies with income class, but difference in the generation is not so much as that in age of householder.

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The seasonal amounts of dry and fog water depositions onto a mountain forest canopy were estimated together with those of stem flow and leaching (or absorption) by a method based on both water and material balances. The maximum water retained on the forest canopy that was estimated from the intercept of the regression line of the bulk precipitation versus throughfall was used for calculating the water balance. The coefficient of interception loss (k) was used in the equation for calculating the interception loss. Two conditions were set for calculation of the k values. One is the high correlation (r2> 0.95) between the volume of the fog sample and that of the fog water deposition in their seasonal data. Another is the high correlation (r2> 0.95 ) between the seasonal average of the atmospheric concentration of ions (Ca²⁺, K⁺ and Na⁺) and the corresponding seasonal amount of dry deposition. The variation of the k value in its suitable range gave - 28.3±0.6 % and 11.0±0.7 % changes in the dry deposition amounts of ions and those amounts depositing with fog water, respectively. The similarity of the dry deposition ratios among several ions to those of the atmospheric concentration and the result of the leaching test confirmed the reliability of the calculation using this method. Throughfall was collected every 2 weeks in the pinus densiflora forests (altitude 850 m) adjacent to cities. The seasonal change in the throughfall pH, high in the summer and low in the winter, are repeated every year. The calculation results explain the mechanism of seasonal change as follows. A significant amount of sulfate and nitrate ions deposit on the leaves in both the spring and summer so that the corresponding H⁺ tends to be generated. However, the H⁺ generation is simultaneously depressed in the summer by both the exchange reaction with K⁺ and the absorption of nitrate ion by the leaves. As a result, the throughfall pH increases in the summer. The pH decreases in the winter because only a small amount of K⁺ leaches from the leaves in that season in spite of the supply of sulfate and nitrate ions from the fog and dry depositions.

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