The lifecycle inventory was analyzed for vinegar glass bottles (500 ml), and the environmental loads analysis of these bottles was carried out by the use of the LCI software, which was suited for various kinds of food glass bottles . This LCI software features introduction of several changeable parameters such as the bottle weight, the number of times that the bottle is reused, and the distance of recovered bottle transportation, etc.. Lifecycle environmental loads of one-way and returnable bottles were analyzed for several cases by changing these parameters . It is generally considered that returnable bottles give less environmental loads than one-way bottles. However, in the case of low recovery ratio of returnable bottles, it showed that returnable bottles gave more environmental loads than one-way bottles . It is preferable that the number of reuse times for returnable bottles is more than three times (recovery ratio is over 67 %) .

View full abstract

Ammonium sulfate is often applied as snow cement on ski run during racing ski competition in Japan. The purpose of our study is to make clear behaviors of ammonium sulfate and the effects upon snow, water, soil and vegetation, because a large amount of ammonium sulfate applied on field has possibility to give various impacts on environments such as vegetation change, water pollution, and soil acidification. Snowmelt water included high concentration of applied ammonium sulfate on snow surface and ran off from snow rapidly . This runoff with high concentration of snow cement may have effects on surroundings suddenly and strongly. However, the effects on stream and underdrainage waters were relatively small due to buffer effects that soil adsorbed and kept both NH₄⁺ and SO₄^2- . A great part of ammonium sulfate kept within soil after thaw causes vegetation change, water pollution by nitrate nitrogen, and falling of soil pH.

View full abstract

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofuranz (PCDFs) in the atmospheric environment at a suburban city in Kanto area were examined using data measured at 30 points at about 2km mesh in two seasons, winter and summer, on two days each. While there was little systematic change in concentration distribution, average concentration changes depending on the date of the measurement. Relatively good correlations were found between suspended particulate matter (SPM) concentration and PCDD/Fs concentration. Taking into account the weather condition of the day with high concentration measured, major emission sources of PCDD/Fs are considered to be distributed near the ground surface widely. The concentration of Co-PCB was estimated approximately 6% of PCDD/Fs. The life time of PCDD/Fs beneath a ground Surface was estimated using deposition of PCDD/Fs to the ground surface derived from an annual average concentration of PCDD/Fs in the atmosphere and deposition rate, and measured dioxin concentrations in soil. The estimated life time is on the order of seven to ten years. Emission strength of dioxins was estimated using a simple diffusion model assuming the emission sources are near the ground surface and are distributed horizontally and randomly. Total emission strength in Japan, estimated with the assumption that the emission strength is in proportion to population, may be on the order of kg-TEQ/y. This is on the same order of the value that derived from source inventory through an official investigation. The results suggest that small but many unknown sources still exist widely.

View full abstract

We investigated the relationship between ionic concentrations and the sulfuroxidizing activity of microorganisms in aerosols and rainwater . Aerosol and rainwater samples were collected in Niigata City over a period of one and four years, respectively. Aerosol and rainwater were examined for microbial sulfur -oxidizingactivity in pH 4.0, 6.0 and 3.5 culture medium which contained sodium thiosulfate as anenergy source. The sulfur-oxidizing activity was measured as thiosulfate consumptionand sulfuric acid formation . We found high concentrations of Ca²⁺ and NH₄⁺ and lowconcentrations of Na+ and SO₄^2- in the aerosol component from December to May.Little sulfur-oxidizing activity by microorganis was found in the aerosol .Highly significant correlations were shown between the nss-SO₄^2-- and nss-Ca²⁺concentrations in the autumn and spring rainwater . In rainwater, we suggest 2 typesof sulfur-oxidizing microorganisms one of which oxidizes thiosulfate to sulfate in theculture media of pH 6 and pH 3.5 while the other is able to oxidize thiosulfate but notto sulfate in the same media with pH 6.For rainwater which had the higher sulfur-oxidizing activity in the pH 3.5 and 4.0culture medium, ratio of nss-SO₄^2- to the total-SO₄^2- was high. We investigated the relationship between ionic concentrations and the sulfur oxidizing activity of microorganisms in aerosols and rainwater. Aerosol and rain water samples were collected in Niigata City over a period of one and four years, respectively. Aerosol and rainwater were examined for microbial sulfur -oxidizing activity in pH 4.0, 6.0 and 3.5 culture medium which contained sodium thiosulfate as an energy source. The sulfur-oxidizing activity was measured as thiosulfate consumption and sulfuric acid formation . We found high concentrations of Ca²⁺ and NH₄⁺ and low concentrations of Na⁺ and SO₄^2- in the aerosol component from December to May.Little sulfur-oxidizing activity by microorganis was found in the aerosol. Highly significant correlations were shown between the nss-SO₄^2-- and nss-Ca²⁺ concentrations in the autumn and spring rainwater . In rainwater, we suggest 2 types of sulfur-oxidizing microorganisms one of which oxidizes thiosulfate to sulfate in the culture media of pH 6 and pH 3.5 while the other is able to oxidize thiosulfate but not to sulfate in the same media with pH 6. For rainwater which had the higher sulfur-oxidizing activity in the pH 3.5 and 4.0 culture medium, ratio of nss-SO₄^2- to the total-SO₄^2- was high.

View full abstract

A water quality tank model based on the water and nitrogen balances in Tone basin of Gunma Prefecture was developed to estimate nitrogen concentration of the river and used to discuss the way to reduce the nitrogen load. The water quality model consists of sixty tanks. The linkage of the tanks was determined by structure of rivers in Gunma Prefecture. The difference between the nitrogen loads generated in the basin and discharged into Tone River was given as diminution by denitrification and / or adsorption. The suppositional height of the tanks and the rate constant of nitrogen diminution were determined by the method of parameter fitting. The values of the tank height and rate constant were 7 .0 m and 1.5×10^-4/day, respectively. The simulation was carried out to discuss the way to reduce the nitrogen load using four scenarios obtained from the historical change of the nitrogen load. The calculated results indicated that nitrogen load generated from both rural and urban areas affected the water quality of Tone River. It was considered that recycling of livestock waste could be best way in the rural area of a high nitrogen load. In addition, utilization of livestock waste as energy source and treatment of the waste by advanced nitrogen removal process were proposed . In the other area, improvement of wastewater treatment plant is recommended to reduce the nitrogen load generated from anthropogenic activities.

View full abstract

This paper is an attempt to clarify environmental problems related to the recent developments in agriculture and industry. The study area is the Hebei Plain which occupies a large area in the Hebei Province of China. With the development of the regional economy, the environment of water use has changed. This change is associated with the decline of the groundwater level, expansion or reduction of salinized soil area. In this paper, first the available water resources of the Hebei Plain are discussed on the basis of the geology and hydrogeology of the area. Next, the secular changes of land use and water use are considered, and the accompanying decline or lowering of groundwater level, the changes of the salinized soil areas, and land subsidence are discussed. Finally, some countermeasures of effective use of water resources are presented, such as water saving, use of salt water, reinforcement of water resources managements and inter-basin transfer of water from the Changjiang River.

View full abstract