Structural changes in the hepatopancreas of the rock lobster,Jasus edwardsii (Crustacea: Palinuridae) during development from the puerulus to post-puerulus

There is evidence for non-feeding in pueruli of palinurid lobsters during their long-distance swim to the coast and the succeeding post-settlement phase until they molt to the juveniles. For a better understanding of the nutritional supply during the puerulus stage, structural changes in the hepatopancreas were studied in post-settlement pueruli and first-molt, postpueruli of the rock lobster, Jasus edwardsii, collected on the southeast coast of the North Island, New Zealand between 1989 and 1990. In newly settled (transparent) pueruli, the epithelium of the hepatopancreas is dominated by presumed young R-(resorptive) cells, which are devoid of lipid droplets, but show active uptake of material from the hemolymph through pinocytosis at the basal region. In the fully pigmented puerulus, the hepatopancreas is dominated by R-cells containing massive lipid droplets; also present are small numbers of F-(fibrillar) and B-(blister-like) cells. This increase of lipid inclusion in the R-cells corresponds to the reduction in size of the fat bodies as the lobster develops from the transparent to the pigmented puerulus. After the molt to the post-puerulus, the R-cells are compressed, and the lipid droplets almost disappear, while the B-cells increase both in size and number. A mechanism is proposed in the present paper to explain energy storage and utilization during the puerulus and post-puerulus stages, wherein the fat bodies and the lipid inclusions play a vital role.     

Sources of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs), and their bioaccumulation through the marine food web in Sendai Bay,Japan

The concentrations of PCDD/F and Co-PCB congeners in seawater, sediment, Pacific oyster, Japanese anchovy, marbled sole, and Japanese flounder samples from Sendai Bay, Japan, were analyzed. The compositions of total PCDD/F and total Co-PCB concentrations in sediment and Pacific oyster reflected that in seawater--the compositions of total PCDD, PCDF, and Co-PCB concentrations were approximately 60, 10, and 30%, respectively. The compositions in Japanese anchovy, marbled sole, and Japanese flounder were different from those in seawater and sediment-the ratio of total Co-PCB concentration to total PCDD/F plus Co-PCB concentrations in Japanese anchovy, marbled sole, and Japanese flounder was above 90%. Tetrachlorinated PCDDs (T4CDDs), such as 1,3,6,8- and 1,3,7,9-T4CDD, were the predominant congeners in seawater and sediment; the total T4CDD concentrations in seawater and sediment were approximately 46 and 48% of the total PCDD concentration. Furthermore, shipments of the herbicide 1,3,5-trichloro-2-(4-nitrophenoxy)benzene to Miyagi Prefecture, the so-called granary of Japan, were the highest in Japan over the last 12 years. The major sources of PCDD/Fs and Co-PCBs in Sendai Bay, which is in Miyagi Prefecture, are impurities in chlorinated herbicides. The order of concentration of PCDD/Fs was Pacific oyster > Japanese anchovy = marbled sole > Japanese flounder; the concentration in Japanese flounder, which is a higher-trophic-level consumer in the marine food web, was lower than that in shellfish (Pacific oyster) and Japanese anchovy, which are lower-trophic-level consumers. The order of concentration of Co-PCBs was Pacific oyster < Japanese anchovy = marbled sole < Japanese flounder; the concentrations in the higher-trophic-level consumers were higher than the concentrations in the lower-trophic-level consumers. Different PCDD/F congeners tended to bioaccumulate in different organisms. On the other hand, all species of Co-PCB congener tended to bioaccumulate in all organisms.     

Physical properties and biodegradability of blends containing poly(ε-caprolactone) and tropical starches

In order to assess feasibility of tropical starches (sago and cassava starches) as biodegradable plastic materials, blending with poly(-caprolactone) (PCL), a biodegradable polymer, was carried out. It was confirmed that the physical properties (tensile strength and elongation) of PCL/sago and PCL/cassava blends were similar to those of PCL/corn blend, suggesting that sago and cassava starches can also be blended with PCL for production of biodegradable plastic. However, the properties of all PCL/starch blends were still low compared with those of polyethylene. Enzymatic degradability evaluation showed that lipase degradation of PCL and-amylase degradation of starch increased as the starch content in the blend increased. Burial test of the blends for 1, 3, and 5 months was carried out and the rate of degradation of the PCL/sago blend was confirmed to be slower than those of PCL/corn and PCL/cassava blends. Observation of the film blends structure by scanning electron microscope revealed that the starch was dispersed in a PCL continuous phase. Furthermore, changes in the film surface before and after enyzme treatments were observed.     

Potential of Co2 emission reductions by carbonizing biomass waste from industrial tree plantation in South Sumatra,Indonesia

Approximately half of the carbon in trees can be fixed to charcoal by carbonization. Porous charcoal is useful as a soil amendment for crop fields and forests, and also as a water purifying agent. Given these facts, charcoal production should be recognized as one of the most promising CO₂ sequestration methods. A project on biomass utilization and forest conservation is proposed as a Clean Development Mechanism (CDM) project, by incorporating the carbonization of biomass residue and waste from tree plantations and pulp mills, and also the utilization of carbon products in various fields. A feasibility study was conducted with the existing project of an industrial tree plantation and pulp production in Indonesia. If conventional charcoal-making methods are used, a total of 368,000 t yr^-1 of biomass residue and waste could be transformed into charcoal of77,000 t yr^-1, and the carbon emission reductions by the project reaches 62,000t-C yr^-1 (or 230,000 t-CO₂yr^-1) in consideration of the project baseline. This charcoal project could provide jobs for approximately 2,600people. The soil fertility in man-made forests could be maintained by returning charcoal to the original forests. Therefore, the project would be beneficial to the regional economy. In addition, the present charcoal project is expected to give more positive impacts than negative ones, or leakage, beyond the project boundary. This revised version was published online in August 2006 with corrections to the Cover Date.     

Distribution,life history,and production of three species of <Emphasis Type="Italic">Neomysis</Emphasis> in Akkeshi-ko estuary,northern Japan

Spatial and seasonal distribution pattern, life history and production of three species of Neomysis (Mysidacea) which commonly occur in northwestern subarctic Pacific coastal waters, were investigated throughout the year in the Akkeshi-ko estuary, northern Japan. The most abundant species Neomysis awatschensis (annual mean density: 179.8 inds. m⁻², biomass: 108.8 mg DW m⁻²) occurred at the inner part of the estuary including low salinity areas with no clear preference for the seagrass bed. The second most abundant Neomysis mirabilis (mean density: 95.8 inds. m⁻², biomass: 90.1 mg DW m⁻²) occurred at relatively saline seagrass site throughout the year. Occurrence of Neomysis czerniawskii in the estuary was limited to the seagrass bed during summer when their population mainly consisted of juveniles, suggesting that this species is a seasonal migrant between the estuary and the marine environment. Both N. awatschensis and N. mirabilis populations were composed of two generation types, a larger sized overwintering and smaller sized spring/summer generations; however, each species had a different reproductive strategy. N. awatschensis was characterized by fast growth to maturity at a smaller size than N. mirabilis with a relatively high fecundity during warm season, suggesting that this species is an r-strategist which can utilize opportunistically a wide variety of habitats. In contrast, the seagrass bed resident N. mirabilis was a K-strategist which matures at a larger size producing fewer but larger offspring. The annual production of N. awatschensis (0.57–0.70 g DW m⁻², mean of the whole estuary) and N. mirabilis (0.58–0.68 g DW m⁻², mean of the seagrass bed) at their respective habitats was comparable. Consequently, species-specific life history and distribution pattern are concluded to allow Neomysis spp. to coexist in the estuary and the high carrying capacity of seagrass bed is suggested to contribute to maintain their high biomass level.     

Simulation study of phytoplankton photosynthesis and growth in the Fraser River estuary

Phytoplankton photosynthesis was estimated by a simulation model of the Fraser River estuary (Canada). For this estimation, two kinds of information were considered; (1) the photosynthetic response of phytoplankton taken from the estuary to each environmental factor; (2) actual measurement of changes in each environmental factor in the estuary. As the major limiting factors, light intensity, temperature, and nitrate were taken into account. Variations in these parameters were combined together under the assumption of the law of the minimum; that is, only one of the environmental factors was considered to limit photosynthesis at any given time and place. From the results obtained, it could be shown which environmental factors actually limited phytoplankton photosynthesis in the Fraser River estuary at different times of the year and at different depths.     

17α-Ethinylestradiol in Lakes of Hanoi and its effect on seed germination

Abstract

The lakes of Hanoi are important water resources for urban agriculture. The concentrations of 17α-ethinylestradiol in the water of three major lakes were found to range from 0.1 to 9.1?ng/L, peaking during the rainy season. Effects at levels from 1?ng/L to 1?µg/L on the germination of mung bean (Vigna radiata) and bok choy (Brassica rapa) were studied. Soaking the seeds in solutions containing 17α-ethinylestradiol at 10?ng/L and higher increased the germination rate of mung bean but not of bok choy. For the latter, irrigation after sowing with solutions containing 17α-ethinylestradiol at 10?ng/L and higher accelerated germination.

Abbreviations: MNRE: Ministry of Natural Resources and Environment; PE₆₀: Population equivalent; USGS: U.S. Geological Survey; SPE: Solid phase extraction; EDTA: Disodium ethylenediaminetetraacetate; HPLC: High performance liquid chromatography; ELISA: Enzyme-linked immunosorbent assay; DOM: Dissolved organic matter; EEQ: Estradiol equivalent     

The weathering of municipal solid waste incineration bottom ash evaluated by some weathering indices for natural rock

The weathering of municipal solid waste incineration (MSWI) residues consists of complicated phenomena. This makes it difficult to describe leaching behaviors of major and trace elements in fresh/weathered MSWI bottom ash, which was relevant interactively to pH neutralization and formation of secondary minerals. In this study, mineralogical weathering indices for natural rock profiles were applied to fresh/landfilled MSWI bottom ash to investigate the relation of these weathering indices to landfill time and leaching concentrations of component elements. Tested mineralogical weathering indices were Weathering Potential Index (WPI), Ruxton ratio (R), Weathering Index of Parker (WIP), Vogt’s Residual Index (V), Chemical Index of Alternation (CIA), Chemical Index of Weathering (CIW), Plagioclase Index of Alternation (PIA), Silica–Titania Index (STI), Weathering Index of Miura (Wm), and Weatherability index of Hodder (Ks). Welch’s t-test accepted at 0.2% of significance level that all weathering indices could distinguish fresh and landfilled MSWI bottom ash. However, R and STI showed contrasted results for landfilled bottom ash to theoretical expectation. WPI, WIP, Wm, and Ks had good linearity with reclamation time of landfilled MSWI bottom ash. Therefore, these four indices might be applicable as an indicator to indentify fresh/weathered MSWI bottom ash and to estimate weathering time. Although WPI had weak correlation with leachate pH, other weathering indices had no significant correlation. In addition, all weathering indices could not explain leaching concentration of Al, Ca, Cu, and Zn quantitatively. Large difficulty to modify weathering indices correctly suggests that geochemical simulation including surface sorption, complexation with DOM, and other mechanisms seems to be the only way to describe leaching behaviors of major and trace elements in fresh/weathered MSWI bottom ash.     

Aerosol concentrations observed at Mt. Haruna,Japan, in relation to long-range transport of Asian mineral dust aerosols

As a part of the effort to understand the structure of long-range transported aerosol plumes and local pollution, aerosol observations monitored the mass concentrations and number-size distributions during the period August 2006 to July 2009 near the top of Mt. Haruna (1365 m), an isolated mountain in the Kanto Plain in Japan. The mass concentrations observed at Mt. Haruna and plain sites showed a seasonal variation with a maximum in spring and summer, respectively. The spring peaks in aerosols at Mt. Haruna were probably caused by long-range transport of mineral dust and anthropogenic particles from the Asian continent. The summer peaks at the plain sites was attributed to local pollution from the Tokyo metropolitan area. Three examples of 2007 Asian dust events were investigated to show that aerosols may be dispersed in a complicated three-dimensional structure and that delayed arrivals of the dust plumes at plain sites compared to Mt. Haruna were not a rare case. Because of the boundary layer being stable at night, the dust layer was advected eastward without the vertical mixing before sunrise. This study suggests that after thermal convection activated by sunlight during daytime Asian dust transported in the free troposphere may be brought down into the atmospheric boundary layer, increasing the dust concentration there.     

Temporal Trends of Non-sea Salt Sulfate and Nitrate in Wet Deposition in Japan

Temporal trends of non-sea salt (nss-) sulfate and nitrate were analyzed from nationwide precipitation chemistry measurements provided by the Ministry of the Environment (MOE) for the 1988–2002 fiscal years (April–March). The concentrations and deposition of nss-sulfate were found to be decreasing, and those of nitrate were stable or slightly increasing at most sites. These deposition trends were discussed from the viewpoint of emissions of SO₂ and NO_X during the period of interest. Because monitoring techniques have changed in the number of active sites, samplers, and analytical methods during the operation period, the median of all annual depositions measured in Japan in a specific year was selected as the annual representative. The contribution of specific emission sources was also calculated for 1990 on the basis of the nss-sulfate and nitrate deposition in Japan obtained with a model simulation in which the model did not include volcanic emissions from Mt. Oyama, Miyakejima Island, which began to erupt suddenly and violently in 2000. For nss-sulfate, the calculated deposition agrees well with the intensity and trends of the median up to 1999. After 2000, a higher deposition than calculated in the preceding years was evident, which is attributable to the volcanic SO₂ from Mt. Oyama. For nitrate, both the calculated and observed depositions were slightly increasing; however, the calculation was found to exceed the observation.