The runoff analysis for urban storm water can be divided broadly into two categories; the storage analysis and the kinematic-wave analysis. These models however have the following problems; modeling of area and pipes is complex and preparation for input-data requires too much load to perform. Therefore, the AR Hydrograph method is presented. The right value of the AR coefficient had the application of wide range. The key point is to gain the value of AR coefficient. The AR Hydrograph method was applied to the modeled runoff patterns, which resulted in the good expression between the concentration time and the AR coefficient. Then, the runoff analysis can be readily performed whether runoff data is found or not.

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This paper investigates measures for lowering surface temperature of pavements for the better urban climate. First, we quantified the effect of albedo, thermal conductivity and heat capacity of pavement on surface temperature mitigation. Then, we showed experimental results of energy balance for permeable pavement with and without water retention, which indicate that the surface temperature of the pavement with water retention is lower 18°C at maximum than without retention, and latent heat is dominant to the net radiation. Finally, the bio-climatic effect of lowering 20°C of surface temperature is estimated by the numerical analysis of human energy balance.

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To calculate life cycle energy (LCE) of sewer systems like conventional gravity system only, alternative gravity system with pumping stations, pressure system and vacuum system, unit energy values of materials were referred from papers but energy consumption of producing process were collected from many factories in Japan. Construction energy was calculated based on standards of cost estimation. Operation and Maintenance energy of pressure/vacuum systems were estimated based on the investigation by interviewing and questionnaire. Energy saved alternatives were considered in each sewer system and 11 alternatives were compared in the condition of 20 ha area, 70 persons/ha, flat and 2m ground water level from surface by LCE converted into annaual value and annual change in case study.

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The 5-point mixture method is used in a survey of the general situation of soil contamination. Its stochastic characteristics were analyzed. Weak stationarity, isotropy, and three types of covariance functions, exponential, Gausian, and spherical type, were assumed for the stochastic characters of a field to be analyzed. The genetic algorithm was used to find the best arrangement of sampling points that minimize the estimation variance in a 1000m² square area. The results show that sampling points should be on the center of the area and about 13m apart from it, although it has been recommended for the standard method that they should be on the center and from 5 to 10m apart from it.

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We evaluated an advantage of the utilization of rainwater and treated domestic wastewater in urban area. The rainwater utilization is the use of rainfall on the roofs and collected runoff storm water in the storm water reservoir for flood control. In the reuse of treated domestic wastewater, wastewater from the kitchen is not reused. That is “Domestic Water Recycling System”. We evaluated the amount of conserved drinking water and the amount of decreased final effluent polluted matters by the unused water resources utilization. And we estimated the amount of carbon dioxide emission by the construction and operation of the unused water utilization systems. In the subject basin, the use of rainfall on the roofs and the domestic water recycling systeip are effective in the decrease of the resources consumption. And the domestic water recycling system is the most effective in the decrease of the environmental load.

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The effect of solid content on anaerobic digestion of dewatered sewage sludge under mesophilic (35°C) conditions were investigated using continuous digester. The experiments were carried out by changing the moisture content of dewatered sludge. The COD, TS and VS removal efficiencies were changed from 47.1% to 38.3%, 38.8% to 23.6% and 45.6% to 33.8% respectively, as the solid content increased from 3% to 11%. When the solid content of sludge fed to digester was higher than 8.9%, the carbohydrate removal efficiencies and methane production rates were decreased.

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The sap temperature changes by heat exchanged between the tree and its external environment, for example, the air temp., the insolation, and the wind, when the sap is rising in the stem from the root. The good growth tree exchanges less heat from its external world than the bad one, because its amount of flow is more and its bigger crown mitigates the thermal environment of the stem and the root. The relatiive change of sap temp., which is the change of the sap temp. passing through a fixed length stem divided by the air temp. that is the forecast maximum change, is related to the tree vigor judged with the four-ranking method by the Science and Technology Agency.

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PHA (Polyhydroxyalkanoate) known as carbon storage polymer in microorganisms recently draws attention as a biodegradable plastic. It is known that the microorganisms in activated sludge can produce PHAs, and PHA production by activated sludge is worth being focused in the aspects of the recovery of organic from wastewater etc. In this research, the PHA production using activated sludge was investigated with special focus on the effect of substrate composition on the PHA structure and the influence of presence of nitrogen compounds on the PHA production efficiency. The results showed that the ratio of 3HB and 3HV monomers in the PHA produced was regulated (3HV ratio is 3-84%) by changing the ratio of acetate and propionate in substrate. It was also indicated that activated sludge can produce PHA under non-nitrogen-limitting condition. In general PHA production is inhibited under this condition.

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Characterization of highly concentrated activated sludge in high strength fermentation wastewater treatment coupled with UF membrane is presented. High TOC and NH₄-N removal efficiencies were obtained by this process. Specific nitrification rate in continuous experiment was found to have the same trend as that in batch experiment, and specific denitrification rate in continuous experiment was much lower than that in batch experiment. Specific oxygen utilization rate and specific INT-dehydrogenase activity of sludge decreased slightly, however, the volumetric activities of both increased remarkably with the increase of MLVSS. The filamentous bacteria were predominant at lower MLSS and coccus-like or rod-type bacteria at higher MLSS.

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In order to make clear endurace swimming speeds of fish, author carried out hydraulic experimental tests using wild fish. Endurance swimming speeds of fish based on the results, during 60 minutes, are as follows: Salvelinus leucomaenis (PALLAS) f. pluvius (HILGENDORF) and Leuciscus (Tribolodon) hakonensis GUNTHER is 85cm/s, Cyprinus carpio Linnaeus is 70cm/s. Carassius carassius buergeri (TEMMINCK et SCHLEGEL), Carassius gibelio langsdorfi (VALENCIENNES) and Zacco platypus (TEMMINCK et SCHLEGEL) are 65cm/s. Zacco temmincki (TEMMINCK et SCHLEGEL) is 55cm/s. Those measurement values are 100% endurance swimming speeds in a scope of activity water temperature of fish upper the 12-13°C. however, those speeds are decreased under the 8-9°C. It is in tendency that endurance swimming speeds are in mainly proportion to fish lengths

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