Scopelophila ligulata, a species of “copper moss”, is known to prefer a strongly acidic substrate. The soluble chemical elements in the substrate of Scopelophila ligulata and those of four other non-copper mosses which grow on the vertical rock face of the same black slate (Chichibu Paleozoic strata), were examined. The following results were obtained: (1) The pH and the concentrations of water-soluble iron and sulfate in the substrates of Scopelophila ligulata showed a significant difference from those of the other mosses. (2) A high correlation was found among the pH, the concentration of water-soluble iron and that of water-soluble sulfate. (3) The concentrations of watersoluble copper and zinc in the substrate of Scopelophila ligulata were much lower than those of water-soluble iron.

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Diurnal and seasonal variations of the methane absorption rate on forest soils were measured in temperate forests in central Japan. The measurements were conducted by the closed chamber technique from April, 1991 to March, 1993. The results obtained from a climax natural evergreen oak forest indicated that the diurnal changes in the absorption rates were small and not periodic. The measurements taken during a two year period in a climax natural evergreen oak forest, deciduous broad-leaf secondary forests, a Japanese red pine secondary forest and a Japanese cypress plantation showed absorption rates in the range of 0.03-0.10, 0.01-0.09, 0.01-0.04 and 0.02-0.05 mg CH₄m^-2hr^-1, respectively; and higher absorption rates were observed from late summer to autumn. Spatial variation of the methane absorption rate on forest soils was also observed; possible correlations between some soil environments and the absorption rates were discussed. No significant correlation was observed between soil pH and the methane absorption rate, while a slight positive correlation was found between the absorption rate and soil porosity.

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The purpose of this paper is to estimate the environmental value of recycled wood wastes in water cleaning purifiers using conjoint analysis. Choice experiment elicitation method has been made. Empirical study of recycled water cleaning filter made from wood wastes shows that marginal willingness to pay of removing trihalomethane is 3, 088 yen per one filter and environmental value is 1, 005 yen. When recycled good has same quality as non-recycled goods, recycled good can make larger market share than non-recycled goods at same price. However, in the case that the quality of recycled good is lower than non-recycled goods, recycled good have no market power and the share of recycled good is under 10 % at same price. These results means that recycling value is secondary value of goods.

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Economics development in Asia has effected land use change. In this model, income is obtained from a calculation involving capital and labor using the Cobb-Douglas function, then the ratio of urban population is calculated from income and it is applied for estimating the future land use change in Asia.

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Manganese (Mn), chromium (Cr) and copper (Cu) are essential elements. However, excessive ingestion of or exposure to these metals may lead to Parkinsonism-like symptoms (Mn), allergic dermatitis, nasal septal perforation and lung cancer (Cr), and Wilson's disease (Cu). Based on the results of studies on time-lapse changes in heavy metal levels in human organs and tissues, changes in metal accumulation have been found to vary with each metal and organ. It is known from measurements of heavy metals in neonates that high levels of heavy metals are transported through the placenta and accumulated in fetuses. Since the occurrence of Minamata disease, attention has been focused on mercury transported through the placenta, mercury levels mainly in the placenta, maternal and umbilical cord blood, and hair. In contrast, only a few reports have concerned the accumulation of heavy metals other than mercury in the umbilical cord. Measurements of heavy metals in maternal and umbilical blood may provide useful information regarding short-term (several days to weeks) or chronic contamination. The umbilical cord, a fetal tissue, is the route through which life-maintaining substances are trans ported from the maternal body. Although contaminants such as heavy metals are directly Measurements of heavy metals in maternal and umbilical blood may provide useful information regarding short-term (several days to weeks) or chronic contamination. The umbilical cord, a fetal tissue, is the route through which life-maintaining substances are trans ported from the maternal body. Although contaminants such as heavy metals are directlyMeasurements of heavy metals in maternal and umbilical blood may provide useful information regarding short-term (several days to weeks) or chronic contamination. The umbilical cord, a fetal tissue, is the route through which life-maintaining substances are trans ported from the maternal body. Although contaminants such as heavy metals are directly accumulated in fetuses through the umbilical cord, they are in part accumulated in the umbilical cord before reaching the fetuses. In Japan, we have the tradition of retaining the dried umbilical cord over a long period of time, and therefore, it is convenient to investigate retro spectively the level of contamination in the umbilical cord. It is also easy to compare different contamination levels over many years. We compared the results of the present study with those obtained previously to investigate the changes over ten years.

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We previously reported on bacteria that are able to degrade an organophosphorus insecticide, fenitrothion (MEP), which is a thionoester compound with a nitro group. In this, study, bacteria that can degrade chlornitrofen (CNP), a diphenylether herbicide with a nitro group, and diazinon, a thionoester organophosphorus compound without a nitro group were investigated. Biodegradability of CNP was observed in Tempaku river water at all time points and diazinon-biodegradability was observed in a range from no degradation to nearly 80% by Handai method. Bacteria with CNP-degrading abilities of over 10% were 46 of 158 isolates from river water and 43 of 77 isolates from the cultured fluid of river water with CNP, and many of those isolates belonged to types of bacteria with MEP-degrading ability. Diazinon-degrading bacterum with abilities of over 10% was only one of 40 isolates from river water, but many diazinon-degradable bacteria were isolated from the cultured fluid of river water with diazinon for 2 weeks. One of isolates, it was identified as Pseudomonas alcaligenes, showed a high CNP-degrading ability and a low MEP-degrading ability, but did not degrade diazinon. An Acinetobacter lwoffii from the cultured fluid of river water with diazinon degraded both MEP and diazinon, but did not degrade CNP.

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