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41.
The phylogenetic status of Alaysia-like vestimentiferans, which were collected at eight sites in the western Pacific, was analyzed on the basis of the nucleotide sequence of part of a mitochondrial gene for cytochrome oxidase I. The 123 individuals analyzed were tentatively classified into four species, which inhabit, respectively, seep areas off the central part of the Japanese mainland, hydrothermal vent fields in the Mid-Okinawa Trough, hydrothermal vent fields in the southern Okinawa Trough, and both seep and vent sites in the Bismarck Sea. From six additional lamellibrachiid specimens from two sites in the Bismarck Sea, two new tentative species were recognized, namely, one from a seep area off Papua New Guinea and another from the hydrothermal vent field at the DESMOS site in the Manus Basin. Phylogenetic analysis using all available sequences of six vestimentiferan families and Alaysia-like vestimentiferans revealed that vestimentiferans could be divided into three groups, namely, lamellibrachiids, escarpiids, and others, even though the monophyly of the third group was supported by only low bootstrap probabilities. Within the first group, the earliest divergence of a tentative lamellibrachiid species from the DESMOS site was apparent. All Alaysia-like vestimentiferans formed a monophyletic group with Arcovestia ivanovi from the Manus Basin, and it is suggested that this group might be derived from vestimentiferans that are endemic to the hydrothermal sites in the Eastern Pacific Rise.  相似文献   
42.
Larval dispersal and recruitment are important in determining adult coral distribution; however, few studies have been made of coral larval dispersal. This study examined the larval behavior, survivorship competency periods and settlement of two brooding corals, Heliopora coerulea and Pocillopora damicornis, in relation to different potential larval dispersal patterns. We also examined the lipid content of H. coerulea as a means of flotation and a source of energy. Planulae of H. coerulea were on average 3.7 mm in length, lacked zooxanthellae, and were mostly benthic, probably because of restricted movement and low lipid content (54% by dry weight). Planulae of P. damicornis were on average 1.0 mm in length, had zooxanthellae and swam actively. The competency period of H. coerulea was shorter (30 days) than that of P. damicornis (100 days). Forty percent of H. coerulea planulae crawled onto the substrata within 1 h of release, and 47% settled within 6 h. By contrast, fewer than 10% of P. damicornis planulae crawled onto the substrata within the first hour and 25% settled within 6 h of release. The planulae of H. coerulea may have a narrower dispersal range than those of P. damicornis, settling and recruiting near parent colonies. Thus, brooding corals exhibit variations in larval dispersal patterns, which are characterized by their position in the water column and competency periods.  相似文献   
43.
44.
The present study reports on the mercury concentrations of the vestimentiferan worm, Lamellibrachia satsuma, (Annelida: Pogonophora) found near hydrothermal vents at a depth of 80-100 m in the northern parts of Kagoshima Bay. The vestimentiferan worms had total mercury concentrations of 238 ng/g in the anterior muscle of the body and 164 ng/g in the posterior trophosome. Methylmercury constituted only 7.6% of total mercury detected anteriorly and 16.3% posteriorly. The mean total mercury concentration in filtrated ambient seawater of the worm habitat was 1.1 ng/l. The worm should accumulate mercury in seawater by a one-step into the anterior and posterior parts as 2.2 x 10(%) and 1.5 x 10(5) times those of the filtered ambient seawater, respectively. The bioaccumulation factor of mercury by the worms with only their respiration would be actually larger than that by other marine animals through food webs. The high bioaccumulation factor of mercury in the worms suggest the following two possibilities: (i) the biological half-life of organomercury in the worm could be exceptionally long; or (ii) the lifetime of vestimentiferan worms examined in the present study could be extremely long. Various metals in one specimen of the worm were analyzed by using ICP-MS, and then gold as well as silver were detected in the worm. Gold was detected for the first time from marine animals.  相似文献   
45.
Formation and decomposition behaviors of PCDD/Fs during pyrolysis of polyvinyl chloride (PVC) with CuO have been investigated. These reactions proceed simultaneously, and the rate of decomposition exceeds that of formation with further retention. More 2,3,7,8-TCDD is formed when the dechlorination of PCDD/Fs proceeds significantly. Homologue profile patterns of PCDD/Fs show that the fractions of O8CDD and H6CDFs are relatively larger within PCDDs and PCDFs, respectively. Extremely large amounts of PCDD/Fs are obtained with the long retention time at 200 degrees C. The formation of PCDD/Fs decreases drastically with increase in the molar ratio of CuO/PVC. The acceptability of thermodynamic calculations on the formation of PCDD/Fs is also investigated. The thermodynamic calculated tendency of the effect of oxygen on the formation of PCDD/Fs agrees well with the experimental results, although absolute values of the amount of PCDD/Fs are much different.  相似文献   
46.
Bioconcentration factors (BCF) for pentachlorophenol (PCP) and 2,4-dichlorophenol (2,4-DCP) in Japanese medaka (Oryzias latipes) were determined at five different concentrations of the chemicals, between 0.1 and 10 microg/l (PCP), 0.3 and 30 microg/l (2,4-DCP), in the ambient water. Medaka were exposed to each chemicals in a continuous-flow system during the embryonic development period and 60 days after hatching from eggs collected in the laboratory. Both the exposure time and the aqueous concentrations are much more realistic and closer to natural aquatic environments than those used in conventional BCF studies. The BCF values of PCP were from (4.9+/-2.8)x10(3) at the aqueous concentration of 0.074+/-0.028 microg/l to (2.1+/-1.4)x10(3) at 9.70+/-0.56 microg/l. The BCF value of 2,4-DCP were from (3.4+/-3.0)x10(2) at 0.235+/-0.060 microg/l to 92+/-27 at 27.3+/-1.6 microg/l. Generally, BCF values increased as the aqueous concentrations of PCP or 2,4-DCP decreased. This finding suggests that a relatively low and realistic aqueous concentration of these compounds is necessary to more accurately determine their BCF values in natural aquatic environments. Conventional BCF experiments at higher aqueous concentrations may underestimate the BCF values.  相似文献   
47.
Journal of Material Cycles and Waste Management - The use of agro-residue in resource-limited regions can be a smart way for civil construction to reduce costs, reduce emissions of pollutant gases...  相似文献   
48.
This study aimed to assess Japan’s recent “local production for local consumption” (LPLC) movement, with a special focus on vegetables in the Osaka city region of central Japan. After collecting statistics and spatial data, we conducted a multi-scale analysis of vegetable production and consumption along with the associated energy consumption, using geographical information system software at three spatial scales along the vegetable flow paths: national, regional, and local. Vegetables consumed in the Osaka city region came from prefectures throughout Japan, and we mapped the foodshed within this region at 1-km spatial resolution, as well as the distribution of farmland, farmers’ and other markets. We also conducted a scenario analysis for reduced energy consumption through organic farming and the utilization of abandoned farmland near a city to replace food imports from distant areas. We found that the large majority of vegetables consumed in the Osaka city region currently come from remote prefectures, and that this is associated with a high level of energy consumption. Inside the Osaka city region, peri-urban vegetable farming contributes to regional vegetable provision, resulting in an approximately 70 % production/consumption ratio within an 80-km radius of the urban center; if all of the area of abandoned farmland were restored to production, this ratio would increase to approximately 75 %. Organic farming activities that bring together farmers and urbanites are emerging in many parts of the study area, contributing to increased LPLC. Scenario analysis suggested that a decrease of more than 1 × 106 GJ of energy inputs could be achieved through wider adoption of local organic farming for local consumption and complete utilization of abandoned farmland in the Osaka city region.  相似文献   
49.
The cerco-fixo is an artisanal fishing trap widely used by traditional communities in the estuarine region of the southern coast of the state of São Paulo, Brazil. The primary goal of the study was to investigate, through ethnobotanical and ecological approaches, the use of plant species by traditional fishermen to build the cerco-fixo at Cardoso Island State Park and Cananéia Island. Ethnobotanical data were collected through interviews, direct observation, plant collection and identification, and document analysis. An ecological evaluation was also done comparing five 20 × 20 m plots in a managed area to five 20 × 20m plots in an unmanaged area, both within arboreal sandy soil vegetation called restinga arbórea, found within the Brazilian Atlantic Forest domain. This study involved 34 fishermen living at Cardoso and Cananéia Islands. The fishermen know more than 90 Atlantic Forest plant species that can be used to build the cerco-fixo. Tree species from the family Myrtaceae were the most quoted in the interviews. With respect to the ecological evaluation, the cluster analyses showed greater heterogeneity in terms of floristic composition (i.e. greater floristic dissimilarity) within the plots of the managed area. The analyses of diversity showed a slightly higher species richness and slightly lower values for Shannon, Simpson, Hurlbert’s PIE and Evenness indices in the managed area (59 species; H′ = 3.28; 1/D = 10.77; E = 0.80; Hurlbert’s PIE = 0.91) compared to the unmanaged area (54 species; H′ = 3.39; 1/D = 20.21; E = 0.85; Hurlbert’s PIE = 0.95). The Hutcheson’s t test showed no significant difference between both areas’ Shannon diversity indices (t: −1.04; p: 0.30). These results are attributed to the greater dominance of the palm species Euterpe edulis Mart. in the managed area (28.2% of the trees sampled at this area; n = 118), which equals twice the percentage of individuals of the same species found for the unmanaged area (14.6% of the sampled trees; n = 48). We discuss the impact of the fishermen’s harvesting practices in the managed area with an emphasis on three main points: (1) the harvesting practices are likely not contributing to a decrease in diversity in the managed area; (2) the greater heterogeneity in terms of floristic composition found for the managed area may reflect a mosaic pattern created by the opening of small tree-gaps distributed across this area over the course of more than 50 years; (3) the disturbance promoted by the fishermen’s harvesting practices can be compared to natural disturbances of low impact that create mosaic patterns in tropical forests. This study emphasizes the prominence of the human dimension in ecological processes and the importance of considering the perspectives of local people when discussing the conservation of the natural environments in which these people live.  相似文献   
50.
Previously, we developed a model to predict lean flammability limit L and flame propagation velocity Sb for pulverized coal. In the present paper, we have extended the model to apply it in development of oxy-fuel combustion systems. The basic model consists of two particles. One of the two particles burns first, then, the other particle is ignited by the heat of combustion of the one burning particle. We analyzed at what distance the first burning particle could ignite the next particle, and how fast the first burning particle could ignite the next particle. The model was verified both for air and oxy-fuel combustion conditions. Next, a method to support burner development was examined by using the model. Local Sb and L near the ignition points of the burner could be analyzed from the concentration and temperature profiles of CFD results. Flame stability was judged by the calculated Sb and L profiles, and past results of blow-off limits obtained with actual- and pilot-scale experiments. A DS®T-burner was developed by Hitachi Power Europe, and installed at the Schwarze Pumpe pilot plant. Combination of the technique and large eddy simulation was applied to confirmation of the system.  相似文献   
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