The leaching mechanism of cations and alminium from soil by acid rain were experimetally studied with soil samples collected from the A and B horizons of soil columns at 28 forest sites in Shiga Prefecture. Cation exchange reactions and the dissolution of aluminium-humus complexes were taken into consideration. Al extracted from soil samples with 0.5 M CuCl₂, which is considered as Al in Aluminium-humus complexes, existed in double amount of exchangeable Al, and existed in high amounteven in soils with low level of exchangeable Al. The Gapon coefficients, K_FB for Ca²⁺+ Mg²⁺ and K_FA1 for alminium, were calculated based on the concentrations of H⁺, Ca²⁺+ Mg²⁺ and Al³⁺ in the solution extracted from the soil samples with pure water, exchangeable Ca²⁺+Mg²⁺ and Al³⁺, and CEC. The values of K_FB and K_FA ranged from 10² to 10³ (mol/L) ^-1/2 and from 10² to 10⁵ (mol/L) ^-2/3, respectively. The values of K_FB based on the extraction tests conducted under different pH conditions were scarcely affected by the equilibrium pH and shown to be approximately the same values as calculated with the water-extrable ion concentrations in each soil sample. The equation of equilibrium Al concentration was experimentally derived as the following equation: pAl³⁺=(2.69×BAR-0.21)×pH+(-12.3×BAR+5.7) where, BAR is bound Al ratio which means mole ratio of carboxyl radical chelating with Al to total carboxyl group included.

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A mathematical model incorporating cation exchage reaction and resolution of aluminum-humus complexes is developed and used to discuss the mechanisms of soil acidification. The model is verified from the viewpoints of the change in concentrations of cations and pH in the leachate from soil exposed to acid rain by comparing the simulated results with data obtained in the artificial acid rain addition experiments. Sensitivity analyses show the importance of Gapon's coefficients for cation exchanege and BAR (bound Al ratio) for release of bases and aluminum and decrease of pH. And Ca+Mg+AI concentration and ratio of (Ca+Mg)/(Ca+Mg+Al) in solution extractedwith buffer solution of 0.5 M acetic acid and anmonium acetate (pH 4.7) are shown to be excellent indices for soil acidification.

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It is necessary to introduce heat cascading into the industrial sector in Japan to reduce carbon dioxide emissions. The aim of this study is to provide an assessment model for heat cascading systems with zero emissions by material circulation, and to evaluate the effects of energy conservation potential by introducing the advanced heat cascading systems. The system consists of four major industry groups and twelve subgroups. The authors have developed an heat cascading model based on linear programming so as to minimize the total system costs, i.e. the sum of fuel, plant and heat transport costs. The results show energy conservation effects of 23% could be realized with the heat cascading. It is suggested that a source group of the discharged heat be combined with a demand group that requires a lower temperature level of heat for zero emissions systems. The simulation results clearly demonstrate the remarkable effectiveness of the heat cascading from the view point of not only heat quantity but also heat quality, i.e. exergy. It was found that discounting the heat transport price could enhance the energy saving performance of heat cascading systems. Applying the mentioned energy systems for the societies 21 st century would create an energy efficient and environmentally friendly city.

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To study the competence of vegetation cover to ameliorate the atmospheric O₃ pollution, the gas exchange rates of O₃, CO₂ and H₂O of 15 woody species were simultaneously measured under 0.1-0.5μL L^-1 O₃. When the woody species were exposed to O₃, the rates of O₃ sorption, transpiration and photosynthesis were decreased in all the species. The O₃ sorption rate was approximately proportional to transpiration rate, indicating that O₃ is predominantly absorbed through the stomata. The tested species showed a wide variety in both sensitivity to O₃ and capacity of O₃ sorption when they were exposed to O₃ : the cumulative O₃ sorption was highest (2.57 kmol m^-2 (mol/mol) ^-1 at 0.5μL L-1 O₃ exposure during 6 h) in Populus nigra and lowest (0.34 kmol m^-2 (mol/mol) ^-1) in Myric rubra; the degree of decrease in photosynthesis rate ranged from 4.1% (Viburnum odoratissimum) to 70% (Populus nigra and Epipremnum aureum) at the end of 6 h exposure. The visible injury was appeared in leaves of Populus nigra, Zelkova serrata and Rhododendron obtusum after the exposure. The O₃ sorption by soils with different water content, grass cover and liquid water was also investigated under 0.5 μL L^-1 O₃. The O₃ sorption rate of dry soils was almost the same as the rate of Populus nigra., However, the sorption rate of the soils was decreased with increasing soil water content. O₃ was almost never absorbed by the liquid water surface. It is concluded that vegetation and soil surface are effective sinks to purify O₃ in polluted atmosphere.

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Scopelophila ligulata (Spruce) Spruce has been called one of the species of copper mosses. Authors focused on the substrate pH and the water-soluble elements such as iron, copper, zinc and sulfate found in the substrates of S. ligulata and other non-copper mosses which grew on same rocks but segregate each other on vertical cliff faces and on cliff shelves, respectively. The following results were obtained. The pH value and the water-soluble iron and sulfate concentrations of the substrates showed a significant difference (p<0.01) between the S. ligulata, which grew on cliff faces, and other mosses found on cliff shelves immediately above the habitat of S. ligulata. Very high correlations (p>0.001) between these three elements were confirmed. The concentrations of water-soluble copper and zinc in the substrates of S. ligulata were much lower than those of water-soluble iron. There was no significant difference in the water-soluble copper and zinc concentrations between the substrates of S. ligulata and those of the other non-copper mosses.

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Concentrations of V, Cr, Mn, Co, Cu, Zn, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Hg, T1 and Pb were determined in the livers, kidneys and muscles of Steller's sea eagle (Haliaeetus pelagicus) and white-tailed sea eagle (H. albicilla) from Hokkaido and golden eagle (Aquila chrysaetos) from Iwate. In general, V, Ag, Cs and Rb concentrations in the liver of raptors were found to be higher than those in other birds reported. Hg and Cd concentrations in the liver of all the raptors were low, but high Pb concentratios were detected in some raptors which remained the lead bullet in the gizzard. A significant positive correlation between Pb and Sb concentrations was observed in the liver of these raptors, indicating that Sb is a useful marker element to evaluate whether lead has been derived from bullet.

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Effect of high magnetic field on Euglena gracilis Z was examined. Euglena was placed in a high gradient magnetic field (380 T²m^-1). Living Euglena moved to higher magnetic field, whereas dead Euglena moved to the opposite side (lower magnetic field). From the in-situ microscope observation, Euglena was found to be oriented approximately perpendicular to the magnetic field regardless of life and death. Based on the above observations the mechanism of magnetotaxis of Euglena was discussed.

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Winter soil carbon dynamics is important as a part of the annual carbon budget in seasonally snow-covered ecosystems. To quantify this dynamics, we improved an open dynamic system for precise and continuous measurements of winter CO₂ fluxes from the soil and snow surfaces which have been measured by less accurate static chamber techniques and/or discontinuous snow CO₂ profile technique. With the devised system, daily trends in CO₂ fluxes from the soil and snow surfaces were measured in a cool temperate forest, together with air and soil temperatures, in December 1994 and January 1995. Measured CO₂ fluxes from both surfaces showed diurnal, changes, following air temperature and/or soil surface temperature. These fluxes were comparable with those measured by the standard techniques in other cool-temperate forests. This reveals that our improved system can measure in situ winter soil CO₂ fluxes, irrespective of the air temperature below 0°C. This successful measurement was attributed to two devices: heater tubing protected air flow in sample gas lines from water vapor freezing, and remote manipulation was able to place chambers on the snowpack without its destruction.

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