The sap temp. of some zelkovas that had differences in the growth before and behind rainfall was measured and the denominator and the numeratore values of the relative changes of sap temp. calculation foumula were compared. The difference in numerator values after rainfall was caused by growth situations and denominator ones showed a constant trend. Because the water stress was improved by rainfall, roots replenished with water. So, denominator values were constant and numeratore ones related to sap rise resulted in differences according to growth situations. Moreover, it was estimated to be able to improve the level of the growth situation by comparing the relative changes of sap temp. after the rainfall with ones before the rainfall.

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  A basin-wide survey on bromide ion concentration was conducted in the Lake Biwa-Yodo River Basin. Bromide ion concentration in the downstram area was approxymately three to four times higher than in the upstream areas of the rivers flowing to Lake Biwa. This result indicated that the contribution of the bromide ion from anthropogeic activities to total bromide ion load was much greater than naturally occuring bromide ion. Also, bromide ion loads from wastewater treatment plants were compared with the land use of corresponding coverage areas, and it was found that significat amount of bromide ion was discharged from commercial and industrial activities rather than domestic activities.

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  In order to provide an index of the environmental burdens associated with remediation of contaminated sites, in this research, we first developed the model to calculate the life cycle CO₂ for 3 remediation methods and 3 risk management methods. Next, we applied this model to heavy metal contaminated site and did sensitivity analysis.
  As a result, life cycle CO₂ of Excavation with Off-Site Disposal method was calculated 212,000 kg-CO₂, the highest among the 6 methods. However as a result of sensitivity analysis, we confirmed that the permutation was changed for site situation except Monitoring method. Life cycle CO₂ of Monitoring of Ground Water method was the lowest among the 6 methods in every condition.

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  The initial effect of dam impoundment on particulate organic matter (POM) dynamics in streams was studied in the forested region of the Ibi River basin, including a newly constructed dam (Tokuyama Dam). In the intact sites, POM fractions larger than 1μm mostly consisted of allochthonous POM and only the largest fraction (> 2mm) reflected the seasonality of litter fall in its concentration. In the downstream section of the dam, only large fraction (> 2mm) showed a sharp decrease in concentration. For POM from 63μm to 2mm, nearly 50% of reservoir-derived POM was exchanged in 3km downstream section. Thus, the downstream POM dynamics probably reflected the low primary production in the reservoir.

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  Heavy metal-contaminated soils are separated into two parts by soil washing, clean sands and highly polluted sludge for further treatment or disposal. At times the so-called clean sands, products of physical soil washing process consisted of wet screen and hydrocyclone, do not meet the soil leaching standard, while satisfying the constituent test.
  Putting the clean sand through the acid extraction process may be an alternative to improve its leaching characteristics, assuming extraction of such mobile portions as water-soluble and acid soluble fractions that are determined by the modified BCR extraction procedure. The process of acid extraction is a complex physicochemical phenomenon of heavy metals of different morphology in the soil. Then, the validity of acid extraction process is only determined experimentally.
  This study has tested three types of acid, hydrochloric acid, sulfuric acid and acetic acid, for typical heavy metal contaminants, lead and fluorine. Two types of feed soil, highly contaminated and lightly contaminated soils, and their underflow of the process or clean sands were subject to acids of different concentrations under different liquid solid ratios. The acid extracted fractions were compared to five soil fractions, water-soluble, acid-soluble, reducible, oxidizable and residue, as determined by the modified BCR method extraction procedure. Generally, the fractions most amenable to metal removal by acid extraction are: water-soluble, acid-soluble (carbonates), and reducible (Fe-Mn oxides).
  As a result, the acid extraction process was valid for reducing lead leaching value to a certain extent, but not for fluorine. It was also observed that the fractionation data by the modified BCR method did not always clearly explain the leaching characteristics of clean sands because a part of mobile portions still remained or some other mobile portions were newly formed through the acid extraction and/or the rinsing processes.

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  An artificial formation of tidal flat is developed to keep the environment of the area along the shore. A new method to develop for an artificial tidal flat circulating resource is suggested. This new method mixes the sand of the shore and dewatered sludge. An artificial tidal flat of 7,200 square meters was developed with this new method at Ago-Bay in Mie prefecture. Authors developed a system of new processing that dehydrates from sludge by low pressure. This report is the result that examined utility to use soil treated by a new processing system to the artificial tidal flat circulating resources. The experiment was carried for 32 months. The experiment investigated a physical characteristic of the bottom soil and the habitation quantity of the benthos. In addition, we evaluated the environmental improvement effect of the artificial tidal flat. We confirmed a lot of benthos and high primary production in the artificial tidal flat that circulated resources.

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