Multivariate analysis of species-compositional data has been recently used to clarify the compositional change pattern of ecological communities, to find out major environmental factors influencing ecological communities, and to support environmental monitoring and planning. Among multivariate approaches, ordination was studied in the present study. General ordination methods were compared one another and effectiveness of them was evaluated. Two sets of species-compositional data, which have already been studied to detect compositional change patterns and environmental factors associating them, were analyzed by six popular ordination methods, namely principal component analysis (PCA), reciprocal averaging (RA), detrended correspon dence analysis (DCA), multidimensional scaling (MDS), polar ordination (PO) and canonical correspondence analysis (CCA). As for CCA, which needs both compositional and environmental data, the influence of replacing environmental data by random values was also studied. The conclusion is as follows. When compositional variation is small (the number of species in the analyzed data set is about three times of the average species richness of a sample or less), PCA with appropriate data transformation performs best. DCA and MDS also show good performance in this case. When the environmental gradients are longer and no association among them exists, DCA will produce usable results. If the gradients have some association with each other, the result of DCA may be distorted while that of MDS will not. In this case it is recommended to confirm the DCA result by CA. It should be noticed that sample scores and species scores are separately obtained by MDS. In many cases this charac teristics is quite inconvenient for community analysis. It should also be considered that the result of MDS may vary with the similarity index used. It was indicated that CCA was more effective method than the other methods studied if enough environmental information is included in the calculation. The effectiveness, however, may decrease when environmental data are not prepared sufficiently.

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We analyze the awareness of the trouble and annoyance of inhabitants within the twenty meters limit of a trunk road through free response data, and compare it with that beyond three hundreds meters from such a trunk road. In the analysis of free response data, we examine the frequency of description words and employ the cluster analysis. By analyzing the frequency of description words in free response data by inhabitants along a trunk road, we found that the word "severe" is used far more frequently than "noisy" in the expression to describe traffic noise. To this usage of the word "severe" in the description of annoying noise, little attention has been paid by researchers of the acoustic environment. By cluster analysis of the free response data along a trunk road, the followings are made clear: Firstly, the residents' awareness is occupied by the overwhelming effect of trouble and annoyance of trunk road traffic, leaving little room for other kind of trouble and annoyance. Secondly, residents recognize pollution phenomena from such a road not individually but as a whole. Finally, the qualitative difference of expression of the same kind of trouble and annoyance shows an unemotional and objective way of description and a vivid and picturesque one.

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Three soil samples amended with two types of sewage sludge were incubated in the laboratory, and analyzed using a sequential extraction procedure to estimate the distribution of Zn, Cu and Cd in 9 soil fractions, that is: Water(water soluble), EX. (exchangeable), L.O.M.(loosely bound to organic matter), CO3.(carbonate), Mn.OX. (manganese oxide), T.O.M.(tightly bound to organic matter), Amor.Fe(amorphous iron oxide), Cry.Fe(crystalline iron oxide), and Res.(residual). These metals were also extracted with DTPA as an index to evaluate the potential availability of these metals to plant grown in soils amended with sewage sludge. After 60 days of incubation, a portion of respective metals changed their distribution, depending on the kind of metals (Zn, Cu and Cd) and on the type of sludge. In soil samples amended with sludge containing lime and iron chloride as dewatering agents, metals were shifted into more insoluble fractions, and their DTPA extractable frac tions decreased. On the contrary, metals tended to be transferred into readily or relatively readily soluble fractions in the soil samples amended with sludge, that had lower pH with polymer dewatering agent, and their DTPA extractable fractions increased.

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Time course of Zn, Cu and Cd redistribution in soil amended with sewage sludges was determined during 60 days of incubation by a sequential extraction method . Changes in proportion of these metals in the soil fractions generally occurred by the first 20 days of incubation, and they were associated with the characteristics of individual metal and the properties of sludges amended . Zn derived from amorphousiron oxide fraction or loosely bound organic matter fraction in sludges tended to be redistributed into residual and manganese oxide fractions. Cu originated from water soluble, exchangeable and amorphous iron oxide fractions in sludges tended to be transformed into less soluble and insoluble fractions (crystalline iron oxide, residual, manganese oxide and/or carbonate fractions). Sludge-derived Cd was rather easily transformed into readily soluble fractions (water and exchangeable fractions) . The type of sludges amended to soil samples markedly influenced the redistribution of Zn and Cd, especially their distribution in readily soluble fractions, but had little effect on the redistribution of Cu, except for an observable effect on the distribution into organic fractions (loosely bound organic matter and tightly bound organic matter fractions).

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The vertical distribution was reported on the concentrations of ambient hydrocar bons [17 volatile hydrocarbon components (VHC), methane, non-methane (NMHC)] and carbon monoxide (CO) measured aloft over Kansai area and at one site near the ground level in Osaka City during the springtime (April 20 and 21) in 1993. The average concentrations of these air pollutants decreased following with the elevated level of sampling sites (ground level, 300 m, 600 m and 2, 000 m). The average percentages of total 17 VHC in NMHC decreased gradually too. Some differences were observed among the average decreasing ratios of vertical 17 VHC concentrations. The concentrations of propylene above 300 m were below the detection limit. The average decreasing ratios of ethylene (C₂H₄) concentrations were larger than those of acetylene (C₂H₂). Above 300 m, atmospheric CO decreased at the more decreasing ratios than acetylene did. Both average ratios of [C₂H₄]/[C2H2] (E/A) and [CO]/[C₂H₂] (CO/A) smoothly decreased above 300 m. From the ground level of one site to 300 m vertically, however, the average ratios of CO/A increased very much and those of E/A gave little change. From these results, it is suggested that the strong influences of the neighboring main emission sources took on the average concentrations of these air pollutants at one site near the ground level, which became to be relatively weak in the case of average concentrations measured aloft over 300 m in a broad area to make the vertical decreases of E/A and CO/A values due to the differences of atmospheric reactions obvious.

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The solubility of two types of commercial nickel oxide particles in five kinds of solvents and in the mouse respiratory tract were examined to estimate the feasibility of an in vitro chemical dissolution test as an alternative method to predict the actual solubility of particulate matter in the human respiratory tract . Green nickel oxide particles, which were well crystallized and contained less oxygen by weight, were completely insolulbe when incubated for 7 days at 37°C under 5% CO₂ and 95% air in distilled water, physiological saline, Hank's balanced salt solution, and Eagle's mini mum essential medium with or without fetal calf serum . On the other hand, black nickel oxide particles, which contained more oxygen by weight, dissolved in all the five solvents under the above conditions, and their solubilities were 25-40%, depending on the solvent. The solubility of these particles in the C3H mouse respiratory tract following intratracheal injection, estimated from nickel kinetic parameters such as lung retention and redistribution to other organs, was 22.3-55.6 and 64.6-76.9% for the green and black nickel oxide particles, respectively. The difference in solubility between the green and black nickel particles, and the difference in solubility observed between the in vitro dissolution test and the mouse respiratory tract are discussed with respect to the physico-chemical characteristics of the particles.

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The gauze collecting methods were investigated which are regulated by JIS and/or ISO for salinity measurement. The ratios of Cl^- to Na⁺ collected on the exposed gauze were 3 times(JIS) or 5 times(ISO) excess of Cl^- present in the average more than the composition of sea salts. The large Cl^- was detectd on the gauzes of JIS and/or ISO methods covered with Teflon filters. The relation between the concentration of coarseCl^- particles ( >2.1 μm) and Cl^- on the exposed gauze was not correlative . It was found that the dry and wet gauzes collect gaseous HCl at high efficiency . Under a high wind, the gauze method regulated by JIS collected some fine Cl- particles( <2 .1 μm) too. One by ISO collected a little. The relation between the concentration of coarse Nay particles and Na+ on the exposed gauze showed a relatively good linear correla tion. Consequently, the gauze collection methos were influenced considerably by gaseous HCl and fine Cl^- particles. It is more proper to estimate the amount of NaCI from Na+ instead of Cl^- collected on the gauze. The amount of salinity in the atmosphere tended to decrese almost exponentially with increasing distance and reduced by a half at 6-8 km distance from the seashore in south Osaka.

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The effect of acids on the germination and growth of the fungus Armillaria mellea was investigated to clarify the relationship between acid deposition and damage to forest by the fungus. The optimum pH for the growth of the fungal hyphae was 6-7. The fungus did not grow at a pH of less than 2.5, but it was relatively acid tolerant and grew within a pH range of 3-4. The optimum pH for germination of the spores was 6-6.5, but no germination was observed at a pH of less than 3. On the other hand, the pH range for germination of the fungus in the presence of soil microorganisms was 4-4.5, and no spores germinated at a pH of more than 5 as a result of bacterial growth. These findings suggest that the increase of Armillaria mellea is favored by acid conditions in the natural environment where the fungus competes with other microorganisms.

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The meaning of b-value in D=D₁*R^b, which indicates the dependence of wetdepostion(D) of chemical species on precipitation amount(R) and constant(D₁), was discussed for the precipitation collected on an event basis during rainy and snowy seasons in the suburbs of Niigata City, which is located on the Japan Sea coast. From the log(R)-log(D) plots, b-values were obtained as the slopes and were compared for the two seasons, among species and with the other reported values. Obtained b-values of all species, except C1^-, for the snowy season were higher than those for the rainy season. Especially, remarkable differences were recognized for NO₃^-, nss-SO₄^2-, NH₄⁺ and nss-K⁺ In other words, the concentrations of these species hardly decrease with R in the snowy season. On the other hand, b-values of sea-salt components (Na⁺, Mg²⁺, C1^-) were nearly equal in the both seasons. The differences of these b-values between two seasons may indicate that NO₃^-, nss-SO₄^2-, NH₄⁺ and nss-K⁺ are ingested into cloud-water by in-cloud scavenging process and are distributed rather homogeneously in snow-cloud which is convective in snowy season on Japan Sea coast, and that the effect of below-cloud scavenging of these species is not stronger than sea-salt components.

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Evaporation pond as drainage system, and irrigation-induced selenium contamination problem in San Joaquin Valley, California were introduced. In south San Joaquin Valley, irrigated agriculture has performed for about 100 years without perfect drainage system. From 1971 to 1982, drainage water from this area was introduced into the reserviors in Kesterson National Wildlife Refuge. In 1982 scientists discovered that irrigation drainage water had contaminated the reservior with toxic level of selenium, and wildlife suffering by selenium toxicity. Now in this area, evaporation ponds are using instead of agricultural drainage system. Since the area of evaporation pond occupy 10% of irrigation land and the pond water contains toxic materials, management of the evaporation pond and purification of pond water are very important for sustaining the agriculture in this area. One of three ponds analyzed in this study contained 8 times of selenium in water compared to US-EPA standard (10ng/ml). Selenium species detected in pond water were selenite, selenate and organic selenium. It was assumed that the dominant inorganic selenium species expected in pond water was selenate. But the results of the present study indicated that the dominant inorganic selenium species in pond water is selenite, and the organic selenium showed a significant amount, suggesting that selenite and organic selenium are important as well as selenate on considering of selenium elimination from water system.

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