Ionic composition of TSP and PM2.5 during dust storms and air pollution episodes at Xi'an,China

TSP and PM_2.5 samples were collected at Xi'an, China during dust storms (DSs) and several types of pollution events, including haze, biomass burning, and firework displays. Aerosol mass concentrations were up to 2 times higher during the particulate matter (PM) events than on normal days (NDs), and all types of PM led to decreased visibility. Water-soluble ions (Na⁺, NH₄⁺, K⁺, Mg²⁺, Ca²⁺, F^?, Cl^?, NO₃^?, and SO₄^2?). were major aerosol components during the pollution episodes, but their concentrations were lower during DSs. NH₄⁺, K⁺, F^?, Cl^?, NO₃^?, and SO₄^2? were more abundant in PM_2.5 than TSP but the opposite was true for Mg²⁺ and Ca²⁺. PM collected on hazy days was enriched with secondary species (NH₄⁺, NO₃^?, and SO₄²) while PM from straw combustion showed high K⁺ and Cl^?. Firework displays caused increases in K⁺ and also enrichments of NO₃^? relative to SO₄^2?. During DSs, the concentrations of secondary aerosol components were low, but Ca²⁺ was abundant. Ion balance calculations indicate that PM from haze and straw combustion was acidic while the DSs samples were alkaline and the fireworks' PM was close to neutral. Ion ratios (SO₄^2?/K⁺, NO₃^?/SO₄^2?, and Cl^?/K⁺) proved effective as indicators for different pollution episodes.     

Assessing the impact of the Japanese 2005 World Exposition Project on vascular plants' risk of extinction

The Red Data Book of Japanese Vascular Plants is based on their risk of extinction. In order to construct the list, 2000 taxa were evaluated using population data and rates of decline for approximately 4400 grids, each of approximately 100 km(2). This database can be used to estimate the impact of human activity on a threatened plant's risk of extinction. In order to evaluate extinction risks and apply the evaluation to conservation actions, the discount mean time to extinction is defined as a measure of extinction risk, where the present value of a species' persistence in the future decreases exponentially. The rate of decrease has to be much less than the rate of economic discounting, in order to realize intergenerational sustainability. Increases of the inverse, and logarithm, of the discount mean time to extinction are considered measures of the extinction risk. We applied these measures to an environmental impact assessment for the Japanese World Exposition that is to be held in 2005. Development will have a greater impact on threatened Salvia species than it will on star magnolia, Magnolia tomentosa, which has been conserved by changing the site plan.     

Hydroponic technique using waste concrete and ferronickel slag instead of fertilizer

Journal of Material Cycles and Waste Management - This paper presents whether some minerals in waste concrete and ferronickel slag are available for hydroponics instead of commercial fertilizer....     

Life history of the temperate subtidal gastropod Umbonium costatum

The life history and reproductive biology of the trochid sand snail Umbonium costatum (Kiener) were investigated on a subtidal sandy shore in Hakodate Bay, Japan between 1988 and 1991. Female U. costatum mature at 1 yr of age (shell diameter-11 mm), reproduce twice (in June-July and September-October) in successive years, grow to a maximum size (shell diameter=22 mm) at age 8 yr, increase annual fecundity with age from 2000 (age 1 yr) to 37000 (age 8 yr), and show a maximum monthly gonad somatic index of 8% which is constant among ages. In comparison to a previously studied life history of a tropical Umbonium vestiatium, temperate U. costatum shows more sustained growth and a longer life span after maturation. This could be explained by: (1) the optimal size model concerned with resource investment, in gametes (Sebens 1987); and by (2) bet hedging to compensate large variability in larval success at high latitudes. These two hypotheses are not mutually exclusive, but both are based on season-related extremes of environment at high latitudes where the period suitable for reproduction is short.     

A possible hybrid zone in the Mytilus edulis complex in Japan revealed by PCR markers

The adhesive protein allele of mussels collected at 13 points in Japan from Hokkaido to Kyushu was analyzed by the polymerase chain reaction using a set of primers which amplifies a part of the nonrepetitive region of the adhesive protein gene. While most mussels exhibited a 126 bp fragment, characteristic of the pure Mytilus galloprovincialis, 55 of 64 mussels sampled at Hiura and 1 of 14 mussels at Hakodate Port exhibited 168 and 126 bp fragments. Sequence analysis of the two fragments indicated that the 168 and 126 bp fragments are almost identical to previously reported sequences in M. trossulus and M. galloprovincialis, respectively. Since the frequency of heterozygous individuals in Hiura is very high, it is unlikely that they are simple hybrids. However, it is evident that mixing of genes occurred between the two species off Hokkaido. Received: 6 September 1996 / Accepted: 9 October 1996     

Comparison of polybrominated diphenyl ethers in fish, vegetables, and meats and levels in human milk of nursing women in Japan

At present, little is known about the occurrence of polybrominated diphenyl ethers (PBDEs) in fish and food products sold in Japan. To investigate whether human exposure to PBDEs through the diet is significant, the concentrations of PBDEs were determined in fish and in meat and vegetables sold in two food markets in the city of Hirakata, Osaka prefecture. The concentrations of PBDEs in the breast milk of 12 primiparae nursing women at one month after delivery also were determined to ascertain the relationship between the levels found in the diet and levels in humans. sigma PBDE concentrations ranged between 21 and 1650 pg/g fresh weight in the edible tissues of five species of fish and one shellfish species. The highest concentrations were measured in yellow-fin tuna, followed by short-necked clam, salmon, yellowtail, mackerel and young yellowtail. Interestingly, sigma PBDE concentrations were not statistically significantly different in two cultured mackerel samples from Japan and mackerel collected from northern European waters. sigma PBDE concentrations in beef, pork and chicken meat (ranging between 6.25 and 63.6 pg/g fresh weight) and in three different vegetables (ranging between 38.4 and 134 pg/g fresh weight) were significantly lower than the concentrations in fish. In human milk, sigma PBDE concentrations ranged between 668 and 2840 pg/g lipid basis, which is comparable to the levels in populations of nursing women reported in Sweden and elsewhere. There was a strong positive relationship between PBDE concentrations in human milk and dietary intake of fish and shellfish, which was established in the women from responses to a questionaire on food consumption habits. The results of this study of food products commonly consumed in Japan and the levels found in nursing women raise a concern about low level PBDE contamination of fish and other foods intended for human consumption.     

Environment and productivities in developed and developing countries: The case of carbon dioxide and sulfur dioxide

We propose a productivity index for undesirable outputs such as carbon dioxide (CO₂) and sulfur dioxide (SO₂) emissions and measure it using data from 51 developed and developing countries over the period 1971–2000. About half of the countries exhibit the productivity growth. The changes in the productivity index are linked with their respective per capita income using a semi-parametric model. Our results show technological catch up of low-income countries. However, overall productivities both of SO₂ and CO₂ show somewhat different results.     

Formation of toxic chemicals including dioxin-related compounds by combustion from a small home waste incinerator

We investigated combustion in a small home waste incinerator and analyzed both flue gas and residual ash for formation of the dioxin-related compounds polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and coplanar polychlorinated biphenyls and their precursors polychlorinated benzenes, polychlorinated phenols, polychlorinated diphenyl ethers, and polychlorinated biphenyls. Particularly, we investigated the effect of the incinerated material's composition on both the congener ratios of released compounds and the total concentration of all congeners of each compound. Eight different samples were prepared for incineration with four samples consist entirely paper, dead leaves, natural wood, or building materials. The remaining four samples contained mostly paper, but also other components such as fiber, non-chlorine-containing plastics, chlorine-containing plastics, and copper electric wire. The presence of non-chlorine-containing plastic in combustion samples did not increase overall dioxin or dioxin-precursor emissions. In contrast, chlorine-containing plastic resulted in a several-fold increase in total polychlorinated dioxins released, in both flue gas and residual ash. Copper wire resulted in a further several-fold increase in total polychlorinated dioxins and dioxin precursors released, with one exception: the addition of chlorine-containing plastic resulted in a many-fold increase in polychlorinated biphenyls, but only a modest further increase ( approximately 52%) with the further addition of copper. Homologue ratios tended toward higher-chlorine compounds as chlorine-containing plastic and Cu were added, but the results were far from uniform. Our results show that toxic dioxin release from small home waste incinerators must be considered significant, especially if even small amounts of chlorine-containing plastics or copper are burned.     

The pollution release and transfer register system in the U.S. and Japan: an analysis of productivity

This study analyzes Total Factor Productivity (TFP), which includes all categories of productivity. Our measure investigates productivity in the context of the provision and dissemination of environmental information policies. We investigated data on the emission of toxic chemical substances for the U.S. and Japanese manufacturing firms, including 386 firms for the period 1999-2007 and 466 firms for the period 2001-2008. The results show that productivity improved in all nine industrial sectors and that pollution levels were high in the U.S. and Japan from 2001 to 2007. In particular, the electronics industry improved rapidly after 2002 in both countries, which may be attributed to the enforcement of RoHS and the REACH directive in Europe. As a result of these stringent policies on toxic chemical emissions, the U.S. and Japanese firms, many of which export to the European market, have strong incentives to reduce their toxic chemical emissions.