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1.
Abstract Deep waters of the Sea of Japan and surface waters of the Pacific Coast of Honshu and the northeast Sea of Japan were analysed for polychlorinated biphenyls (PCBs) pollution. the ΣPCB concentrations in solution in the Sea of Japan (50–3000 m) were between 140 and 1230 fg dm?3. the space-integrated surface water concentration near the Pacific coast of northern Honshu was 140 fg dm?3and for the surface water of the Sea of Japan was 230 fg dm?3. Based on these analyses four water masses were deduced in the Sea of Japan during the summer months. It is shown for the first time in the Sea of Japan that polychlorinated biphenyls are excellent chemical indicators of not only the anthropogenic pollution, but also water masses. 相似文献
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K. Ohwada 《Marine Biology》1972,14(1):10-17
A simple, rapid and sensitive method of microbiological assay for the determination of biotin in seawater has been developed by using a marine bacterium, Achromobacter sp. (Strain yH-51) as an assay organism. When the organism was incubated at 25°C for 48 h in a synthetic medium with constant shaking, a standard reference curve of bioassay was obtained. The organism is sensitive in the range 0.1 to 8.0 ng/l biotin. The distribution of biotin has been determined in the East China Sea, the North Pacific Ocean, and the bays and inlets along the Pacific coast of Japan. Biotin concentrations in surface waters were in the range from less than 0.1 ng/l up to 57.9 ng/l; generally high in coastal waters and low in deep open waters. The concentrations were generally high in surface waters, and rapidly decreased with depth down to 50 m, below which values were generally low. The vertical distribution of biotin followed closely the concentration of chlorophyll a, with high concentrations of biotin restricted to the euphotic layer of high chlorophyll a contents at most stations observed. Biotin concentrations in surface waters were generally high during summer, but in autumn and winter the concentrations decreased markedly. 相似文献
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The relationship between otolith length and body length (total length) was examined in walleye pollock Theragra chalcogramma (Pallas), collected from Pacific Ocean waters adjacent to Hokkaido, Japan, and in larvae reared from fertilized eggs. A linear relationship was found between log-transformed body length and otolith length data with two inflection points at ca. 11 mm and 100 mm total length. This relationship was found to be applicable also to samples from the Japan Sea, Bering Sea and Okhotsk Sea. The early growth pattern estimated by back-calculation of otolith increments of 1-yr fish from Funka (Uchiura) Bay (Hokkaido) accorded with that obtained from size-at-age data of 0 yr fish collected in the preceding year. Differences were found in comparisons of the back-calculated early growth pattern between samples from waters adjacent to Hokkaido, the Pacific Ocean, the Japan Sea and the Okhotsk Sea. The growth curve of the Okhotsk samples was markedly different from others, showing rapid initial growth up to about 100 d after hatching and attaining a small body size in the first year. 相似文献
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Kun Zhang Jialuo Xu Qing Huang Lei Zhou Qingyan Fu Yusen Duan Guangli Xiu 《Frontiers of Environmental Science & Engineering》2020,14(6):92
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Qi YING 《Frontiers of Environmental Science & Engineering》2011,5(3):348-361
The UCD/CIT model was modified to include a process analysis (PA) scheme for gas and particulate matter (PM) to study the formation of secondary nitrate aerosol during a stagnant wintertime air pollution episode during the California Regional PM2.5/PM10 Air Quality Study (CRPAQS) where detailed measurements of PM components are available at a few sites. Secondary nitrate is formed in the urban areas from near the ground to a few hundred meters above the surface during the day with a maximum modeled net increase rate of 4 μg·m-3·d-1 during the study episode. The secondary nitrate formation rate in rural areas is lower due to lower NO2. In the afternoon hours, near-surface temperature can be high enough to evaporate the particulate nitrate. In the nighttime hours, both the gas phase N2O5 reactions with water vapor and the N2O5 heterogeneous reactions with particle-bound water are important for secondary nitrate formation. The N2O5 reactions are most import near the surface to a few hundred meters above surface with a maximum modeled net secondary nitrate increase rate of 1 μg·m-3·d-1 and are more significant in the rural areas where the O3 concentrations are high at night. In general, vertical transport during the day moves the nitrate formed near the surface to higher elevations. During the stagnant days, process analysis indicates that the nitrate concentration in the upper air builds up and leads to a net downward flux of nitrate through vertical diffusion and a rapid increase of surface nitrate concentration. 相似文献
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Vertical distribution and population structure of Eucalanus bungii were investigated at site H in the Oyashio region (western subarctic Pacific) from September 1996 through October 1997 to evaluate the species lifecycle pattern and associated ontogenetic vertical migration. Additional temporary samplings were also made at several stations covering the entire subarctic Pacific, Okhotsk Sea and Japan Sea, as a basis for regional comparison of lifecycle features of this species. At site H, a marked phytoplankton bloom occurred from mid-March to June, and E. bungii spawned in April/May in the surface layer. Resulting nauplii and copepodite stage 1 (C1) formed a prominent abundance peak in early June. The C1 developed and reached C5 by August. The development of nauplii through C4 occurred in the surface layer. From August onwards, C5 and a small fraction of C3–C4 sank gradually deeper, and entered diapause to overwinter at >500 m depth. The C5 molted to C6 males and females in February and March, respectively. The C6 males and females mated at 250–500 m depth, and only mated C6 females ascended to the surface layer in April for spawning. Judging from the size of lipid droplets in the body, the C3–C5 specimens deposited lipids in the body through the phytoplankton bloom period, and the lipids were consumed gradually during overwintering. Taking account of sampling season, temporal changes in population structure, and vertical distribution, the data collected from the western subarctic Pacific and Okhotsk Sea are consistent with a 1-year lifecycle for the site H population, while the data from the central and eastern subarctic Pacific were consistent with a 2-year lifecycle. The populations from the southern and southeastern Japan Sea did not fit the features of either lifecycle scenario, and because of their very small population size it is suggested that they originated from the northern Japan Sea. Regional comparison of the prosome length of C6 females, including those in the Bering Sea, indicated significantly larger specimens from the Japan Sea and Okhotsk Sea, and smaller specimens in the eastern subarctic Pacific, as compared with those in the western subarctic Pacific (including site H) and Bering Sea. A possible overwintering mechanism of E. bungii is discussed.Communicated by O. Kinne, Oldendorf/Luhe 相似文献
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Municipal solid waste (MSW) source-classified collection represents an advancement in resource cycling and secondary pollution control in China. Comparative experiments were performed to assess the levels and patterns of polychlorinated biphenyls in bottom ash, fly ash from boiler, and fly ash from bag filter from an MSW incineration plant with source-classified collection of MSW. Polychlorinated biphenyls were concentrated in the bag filter fly ash and in the bottom ash. The total amount of polychlorinated biphenyls was much lower than in fly ashes and bottom ash from traditional mixed waste incineration. Total concentration of coplanar polychlorinated biphenyls and toxic equivalent quantities were also reduced. Due to variations of feed waste, complete combustion, including continuously high incineration temperature, low CO concentrations and high air excess ratio were observed. Incineration temperature showed a negative correlation, while CO concentration showed a positive correlation with total and coplanar polychlorinated biphenyls, indicating that the latter can be reduced by controlling combustion conditions related to properties of feed waste. 相似文献
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T. Ichikawa 《Marine Biology》1982,68(1):49-60
Particulate organic carbon (POC) and nitrogen in sea water were measured in samples collected in the adjacent seas of the Pacific Ocean during the cruises of T. S. Oshoro-Maru (1969, 1970) and the R. V. Hakuho-Maru (KH-70-4, KH-72-1). High values were obtained in the northern North Pacific and the Bering Sea, the concentration of particulate carbon in the upper 50-m layer ranged from 35 to 550 g Cl-1. In the deep waters of these area, values above 50 g Cl-1 were frequently observed. The lowest values in the surface layer and deeper layers were obtained in the Japan Sea (23 gCl-1) and in the South China Sea (7 g Cl-1) respectively. A consistent minimum was located in the intermediate waters (100–400 m) throughout the entire region studied. Variation with depth was generally irregular with marked peak values in different layers. The POC distribution consited of these peak values and a relatively uniform background concentration. These background values slightly decreased with increasing depth and were different locally. Correlation analysis between carbon concentration and apparent oxygen utilization (AOU) of ambient water for the samples in the Japan Sea and the Sulu Sea showed that there was no systematic decrease of particulate carbon with increasing AOU. In these areas, the carbon concentration scattered in the higher AOU domain ranged from 10–100 g Cl-1. These observations support the conception that downward transport of particulate matter from the overlying surface layer in the adjacent seas of the Pacific Ocean may be fairly rapid. 相似文献
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Carbon monoxide (CO) in the surface sea waters is produced predominantly by photochemical processes, oxidized by micro-organisms and outgassed to the atmosphere. to assess carbon monoxide flux from the oceans to the atmosphere, the photochemical production and microbial oxidation of carbon monoxide in the oceanic mixed-layer was investigated during several oeanographic cruises and in the laboratory. the photoproduction rate of carbon monoxide was found to be well correlated to the concentration of dissolved organic carbon (DOC) in coastal and open ocean surface waters. Taking a global average carbon monoxide production rate of 10 ± 2 nmole litre-1 (mg DOC hr)-1 in the surface open ocean water, and 25 ± 7 nmole litre-1 (mg DOC hr)-1 in coastal sea water, at cloud-free summer solar noon, the photochemical production of carbon monoxide in the global oceans is estimated to be at a rate of 1200 ± 200 Tg CO y-1. the microbial carbon monoxide turnover time in the mixed-layer was observed to range from hours in a coastal estuary to 16 days in the Pacific along 1057deg; W in dark incubations. Natural sunlight can largely inhibit the microbial consumption of carbon monoxide in surface water. On a global scale, microbial consumption is responsible for the loss of less than 10% of photochemical produced carbon monoxide in the surface ocean. Field measurements have shown that the net transport of carbon monoxide from the euphotic zone to the underlying deeper ocean water is limited and that the overall life time in surface sea waters is less than 3-4 hours. When combined, these field measurements with the photoproduction and microbial consumption rates obtained, we estimate the oceanic flux to the atmosphere is about 1000 ± 200 Tg CO y-1, which represents the largest single source of atmospheric carbon monoxide. 相似文献
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There are two approaches in the application of satellite sensors to marine pollution studies. Satellite sensors are used to observe and characterize ocean pollutants such as industrial wastes and oil. in addition, satellite observations provide information useful in illuminating processes such as eutrophi-cation or air-sea exchange of CO2, that are important in determining the distribution and fate of pollutants.
Satellite technology is an important tool in monitoring and studying ocean pollution. Visible sensors have been used to observe and characterize sewage sludge and industrial wastes dumped at sea. Oil slicks have been observed with Landsat, AVHRR and SAR imagery. Besides directly detecting pollutants, satellite sensors are useful for analyzing ocean processes that are influential in the fate of pollutants. These processes include eutrophication of coastal waters and the distribution of suspended matter. the fate of excess CO2 can be addressed using scatterometer-derived estimates of wind speeds to determine the CO2 exchange coefficient at the sea surface on a global scale. 相似文献
Satellite technology is an important tool in monitoring and studying ocean pollution. Visible sensors have been used to observe and characterize sewage sludge and industrial wastes dumped at sea. Oil slicks have been observed with Landsat, AVHRR and SAR imagery. Besides directly detecting pollutants, satellite sensors are useful for analyzing ocean processes that are influential in the fate of pollutants. These processes include eutrophication of coastal waters and the distribution of suspended matter. the fate of excess CO2 can be addressed using scatterometer-derived estimates of wind speeds to determine the CO2 exchange coefficient at the sea surface on a global scale. 相似文献
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The northern Pacific seastar Asterias amurensis Lütken was recently introduced to Tasmanian waters, possibly through ballast water discharged from ocean-going vessels. Three Tasmanian populations and seven native populations from Japan and eastern Russia were examined in 1994 for variation at 22 allozyme loci. There was significant spatial heterogeneity in gene frequencies among the native populations, especially for the ocus APK
*, where G
ST
was a very high 0.47. The Tasmanian populations could not be separated genetically from one another, suggesting they have a common origin from a single introduction. The average heterozygosity per locus of the Tasmanian populations (0.116 to 0.127, mean 0.123) was 30 to 40% less than that of the native populations (0.177 to 0.216, mean 0.192), suggesting that colonisation of Tasmanian waters was accompanied by a population-size bottle-neck. The Tasmanian seastars were genetically more closely related to the two populations from central Japan (Suruga and Tokyo Bays) than to populations from Vladivostok, northern Japan (Yoichi, Nemuro and Mutsu Bays) or southern Japan (Ariake Sea). However, there were significant differences between the populations from Tasmania and central Japan, which may be attributable to founder effects or may mean that the true source of the Tasmanian introduction has yet to be identified. 相似文献
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Bei Ye Zhuo Chen Xinzheng Li Jianan Liu Qianyuan Wu Cheng Yang Hongying Hu Ronghe Wang 《Frontiers of Environmental Science & Engineering》2019,13(6):86
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Zhichao Wu Chang Zhang Kaiming Peng Qiaoying Wang Zhiwei Wang 《Frontiers of Environmental Science & Engineering》2018,12(3):15
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In situ measurement of the urea decomposition rate and its turnover rate in the Pacific Ocean 总被引:1,自引:0,他引:1
The in situ decomposition rate of urea was measured using 14C-labelled urea at 3 areas in the North Pacific Ocean: Sagami Bay on the southern coast of central Japan, the northwestern Pacific central waters and the subarctic Pacific waters. The mean values of the decomposition rates of urea in surface waters of these areas were 44.5, 1.51 and 1.32 mol urea m-3 d-1, respectively. These rates decreased with depth. High rates of urea carbon incorporation into particulate matter and the CO2 liberation from urea carbon into seawater were obtained in light bottles in the euphotic zone, while low rates were found in dark bottles. The turnover rates of urea in the 3 areas were calculated respectively as 12, 113 and 110 d at the surface, and the values increased with depth. 相似文献
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S. A. Mileikovsky 《Marine Biology》1970,6(4):317-334
The pteropod Clione limacina (Phipps, 1774) is an arcticboreal, circumpolar species, which is widely distributed in the North Atlantic and Subarctic Oceans; it also occurs in the North Pacific Ocean (in the Oyashio and neighbouring waters) and along the Atlantic coast of North America in the waters of the cold Labrador current to the Cape Hatteras region (35° N). The distribution of C. limacina larvae in the plankton of the Norwegian, Barents and White Seas, the Bear Island-Spitsbergen region of the Greenland Sea, the Newfoundland Grand Bank and the Flemish-Cap Bank region of the North-western Atlantic Ocean, and the Kurile-Kamchatka region of the North-western Pacific Ocean has been studied, and information from literature concerning the reproduction and larval occurrence of the species is summarized. Throughout its distributional are, spawning of C. limacina is characterized by the same general ecological pattern. This species breeds and spawns in all types of water masses occurring within the vertical range which it commonly inhabits — from surface layers to 500 m water depth. In all local populations of the species, the most intensive spawning is correlated with the spring/summer period of annual heating of the local waters, and the highest abundance parallels maximum growth of phytoplankton which serves as food for veligers and early polytrochous larvae. After the end of this period, spawning intensity in all local C. limacina populations declines sharply, but spawning continues at low intensity during the autumn/winter season, being practically continuous throughout the year. Distribution patterns of C. limacina larvae are determined by those of their parental forms (the parental forms spawn in the zones permanently inhabited). The earliest larval stages of C. limacina (veligers) are present predominantly in the upper 100 or 200 m water layer, i.e. in the zone of high phytoplankton abundance. Polytrochous larvae, after becoming predaceous feeders, are distributed throughout the whole water column from the surface to 500 m depth, similar to adult C. limacina. As with the adults, larvae are present (within the species' distribution area) in all types of water masses. Since the beginning of the twentieth century, in the course of the warming of the Arctic Ocean, the southern race of C. limacina (formerly a summer/autumn seasonal invader in the Norwegian Sea) has become a permanent component of the plankton fauna of the Norwegian and Barents Seas in regions influenced by the Norwegian-Northcape Current System. 相似文献
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为研究嘉兴地区嘉善冬季污染时段和清洁时段PM2.5化学组分特征,结合气象数据对2019年1月嘉兴市嘉善县善西超级站在线自动监测PM2.5及化学组分数据、气态污染物(NO2和SO2)进行了分析.结果表明,2019年1月嘉善善西超级站污染时段PM2.5浓度(97.18μg·m-3)为清洁时段(36.77μg·m-3)的2.6倍.污染时段水溶性离子浓度(41.58μg·m-3)较清洁时段(19.82μg·m-3)高21.76μg·m-3,但占比有所降低,含碳组分比例增加.OC;EC比值为3.93,可能受到燃煤及机动车排放的共同影响.低风速及高湿有利于NO2和SO2等气态污染物进行二次转化,污染时段硫转化率和氮转化率均比清洁时段高,分别增高7.93%和54.11%,说明NOx向硝酸盐二次转化较为明显,导致颗粒物浓度升高.聚类分析结果显示67.34%气流来自北方,且相应的气流轨迹上污染物浓度比周边高,说明污染物存在一定的长距离输送.结合风玫瑰图可以看出,污染主要为本地及其周边的输送,污染物的长距离输送在短时会使污染浓度突增.因此,在重点关注本地及周边污染的同时,偏北气流下的污染物区域输送不可忽视. 相似文献