Environmental valuation at urban waterside area is considered from the viewpoint of improving the waterside as residents around the area desire. The more people use the waterside, the more benefits of improvement on the waterside are generated. So, use values are estimated in this paper. Firstly, a model is set up with the aid of a discrete choice model with perception data. The model explains decision making by the residents around the waterside whether they use it or not. Secondly, the model is applied to a case study on the waterside area in Kawasaki city. Then the model is extended to include the latent variables and the stated preference data. Finally, these models are applied to estimate the environmental values of the waterside. Thus, we can get useful information to improve the waterside area by these models. But a problem of time values that is used to transform the utility into monetary terms has not been solved yet now. So, limitations of the environmental valuation in monetary terms are especially mentioned in this paper.

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The decomposition of dioxin analogues by the infrared (IR) laser irradiationincludes the thermal destruction and the multiple-photon dissociation. It is importantfor the decomposition to choose the laser wavelength which is highly absorbed .The thermal . decomposition takes place by the irradiation of the low IR laserpower. Taking the model of thermal decomposition into consideration, it is proposedin the first time that the adjacent water molecules assist the decomposition of dioxin analogues in addition to the thermal decomposition by the direct laser absorption .

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Cryptomeria japonica seedlings were exposed to the simulated acid fog water with varying pH (2.0-6.4) and inorganic nitrogen concentration (0.05-24meq/l), during 15 weeks (from April to July) at an interval of three or four days. As a result, the concentration of NH₄⁺ +-N+NO₃^- -N in the leaves increased with increasing N concentration in the fog water, however, the foliar concentration of NH₄⁺ +-N was higher than that of NO₃^- N. The concentration ratios of N (NH₄⁺ +-N+NO₃^- -N) to Mg²⁺, Ca²⁺ and K⁺ in the leaves as indicators of the nutritional state of tree leaves increased with increasing N concentration exposed. These were emphasized by the low pH and at the same time the yellow-brown visible foliar injuries were observed in the seedlings. The concentration ratios of N/Mg and N/Ca in the coniferous tree leaves collected at the mountains in the northern parts of Kanto districts where forest declines were observed, were higher than those at other areas in Japan. This might reflect that acid cloud water provided high level of N input. It was suggested that high level N addition to the forest ecosystem over prolonged time period would cause the condition termed "nitrogen saturation" and nutrient imbalance or deficiency of nutrient cations in coniferous trees.

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We measured O₃ levels from May to September 1997 at 3 stations set at different altitudes on Mt Happo, which is located in a remote area of the Japan Alps. At night, O₃ concentrations were correlated positively with altitude, but during the day, O₃ levels at the lower station increased as the mixing layer developed, thus reducing the vertical differences in O₃ concentration. Since it was rare for O₃ concentrations at the lower station to exceed those at the upper station, we concluded that photochemical O₃ formation on the mountainside was negligible, and that the data represented background ozone levels. We then calculated the contribution of photochemical O₃ formation in city areas to total O₃ (O_x) levels by subtracting the background O₃ concentrations obtained on the mountainside from the O_x levels measured in the cities. These calculations were performed for periods when O_x concentrations exceeded the environmental standard (more than 60 ppb). In the cities of Nagano, Omachi, and Matsumoto, which are located around Mt Happo, photochemical O₃ contributed a minimum of 18%, 19%, and 20%, respectively, to O_x levels in May. These percentages increased during summer, and reached a maximum of 40%, 37%, and 41%, respectively, in September. In contrast, the O_x dose (ppb h) showed a spring maximum and a summer minimum .

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Using nationwide sampled face-to-face interview survey results, whose respondents were randomly sampled male and female who are 16 years old and over, by National Institute for Environmental Studies in 1997, September, we 1) examined the structures and relationships of general value systems and values on the environment, 2) analyzed the relationships between pro-environmental behaviors and general values, values on the environment, and demographic variables . Our results showed 1) structural differences of general values between Japanese samples and the US sample surveyed by Stern et., al., especially the relationships between traditional factor and ecological factor . 2) In political environmental action, the value on the environment is positively significant, but in other actions such as green consumer behaviors, value on the environment is not so, rather value on economic progress has negative effects on these behaviors. Obviously, different values and demographic variables have significant effects on different pro-environmental actions. Values on the environment do not always play significant role in pro-environmental actions .

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The levels and seasonal variation of 19 volatile organic compounds (VOCs) in Ise Bay inner coastal area and rivers pour into the bay were studied. In coastal marine, chloroform, bromoform, p-dichlorobenzen and dichloromethane were detected at high concentrations, and in rivers, 1, 1, 1-trichloethane, chloroform, dichloromethane, cis-1, 2-dichloroethylene, o-xylene, trichloroethylene and p-dichlorobenzen were detected at high concentrations. Especially, wide distributions of chloroform in both waters and bromoform in sea were outstanding. The concentration of many chlorinated VOCs showed winter maxima, but with regarding to flowing amounts instead of concentrations, urban rivers receiving domestic and industrial discharge showed summer maxima. Many VOCs components had correlation with each other and with water pollution indicators (BOD, COD, SS, T-N), but 1, 2-dichloroethane and bromoform had low correlation with other chlorinated VOCs or water pollution indicators. Seasonal variations of VOCs observed were thought to be suggesting their plausible origins.

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