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921.
The Baltic Sea ecosystem has suffered from a heavy pollutant load for more than three decades. Persistent organic pollutants (POPs) and heavy metals have been of most concern due to their persistence and toxic properties. Ringed seals (Phoca hispida baltica) and grey seals (Halichoerus grypus) living in the Baltic Sea have been suffering from pathological impairments, including reproductive disturbances, which have resulted in a depressed reproductive capacity. We investigated several biochemical parameters as potential biomarkers for exposure to and effects of the contaminant load in the Baltic seals. Seals from less polluted areas were used as reference material in terms of the pollution load. In both Baltic seal populations, the levels of some biochemical parameters diverged from those in the reference seals, and some of these showed a clear correlation with the individual contaminant load. Of the potential bioindicators, we propose cytochrome P4501A activity and vitamin E levels, in blubber or plasma, as exposure biomarkers for polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT) in both species. The arylhydrocarbon receptor-mediated chemical-activated luciferase gene expression (CALUX) response reflects the whole PCB and DDT burden in ringed seals. Retinyl palmitate (vitamin A) levels showed a negative correlation with the individual POP load, and is proposed as potential effect biomarkers for the depletion of the vitamin A stores. As the nutritional levels of both vitamin A and E have an impact on the vitamin levels in the seals, more information on the dietary vitamin levels is needed before any conclusions can be drawn. As the relationship between biochemical parameters and contaminants varied between the two species, species-specific characteristics has to be considered when monitoring the health status and possible toxic effects of the contaminant load in ringed and grey seals.  相似文献   
922.
In this study, we used the Navy' s Master Oceanographic Observation Data Set(MOODS), consisting of 116019 temperature and 9617 salinity profiles, during 1968- 1984 to investigate the temporal and spatial variabilities of South China Sea thermohaline structures and circulation. For temperature, profiles were binned into 204 monthly data sets from 1968 to 1984 (17 years). For salinity, profiles were binned into 12 climatological monthly data sets due to the data paucity. A two-scale optimal interpolation method was used to establish a three-dimensional monthly-varying gridded data set from MOODS, covering the area of 5°-25°N and 105° - 125°E and the depth from the surface to 400 m. After the gridded data set had been established, both composite analysis and the Empirical Orthogonal Function (EOF) analysis (for temperature only) were used to identify the major thermohaline fratures including annual mean, monthly anomalies, and interannual thermal variabilities. The inverted monthly circulation pattern  相似文献   
923.
Laurencia nanhaiense sp.nov.(Rhodomelaceae,Rhodophyta) is described from Hainan and Guangdong Provinces,China.The new species clearly displays one of the defining features of the genus,viz.four periaxial cells per vegetative axial segment.It differs from other closely related species in having a combination of features such as terete axes from a basal system composed of a primary discoid holdfast and a secondary attachment to give rise to many short rhizoids,branching oppositely and alternately,irregularly tristichous or subverticillately polystichous,having more curve branches with very sparse,adventitious ultimate branchlets,non-projecting superficial cortical cells at the apices of ultimate branchlets,presence of longitudinally oriented secondary pit-connections between contiguous superficial cortical cells,absence of lenticular thickenings in the walls of medullary cells,parallel arrangement of tetrasporangia along the axis of stichidia,and presence of intercellular spaces between medullary cells.  相似文献   
924.
To investigate the life cycle of marine sulfate aerosols, chemicophysical characteristics of marine aerosolswere measured during five cruises in the Pacific Ocean. Dimethyl sulfide concentrations in seawater and in the air were also measured. The geographic variation of sulfate-aerosol concentrations was studied in relation to biogenic and anthropogenic sources,transport with air trajectories, and chemical transformations in the atmosphere. The highest concentrations were found near Asian and American ports, indicating anthropogenic pollution is the major sulfate aerosols source. Higher concentrations were observed in the upwelling regions than in the oligotrophic areas. Along the coastal regions, both mass and number concentrations of sulfate aerosols depended on wind direction and wind speed, and land-breeze and sea-breeze oscillations; no clear diurnal variation was detected. In pelagic areas, along the equator, the concentrations of small sulfate particles showed a maximum in the afternoon and the m  相似文献   
925.
Ⅰ.Losatlon and Historical Development Chukiang or “the winding river” was a castle-like town which was originaIly surrounded by a wall.(Fig. 2)it is situated on the upper part of the Peikiang at the iunction of the Teheng and Wu Riwrs, and is on the crossroad both by land and water (Fig. 1). The city was developed as  相似文献   
926.
正 The earliest known phosphate deposit in China is the Chinpingshan~1apatite deposit in Tunghai district,~2 N.Kiangsu.During the Sino-Japanesewar,a number of phosphorite deposits were discovered in Central Yunnan  相似文献   
927.
928.
929.
正Over 20 sets of dolerite dykes crosscutting Paleoproterozoic basement in West Africa were distinguished via the interpretation of regional and high resolution magnetic airborne data of West African Craton  相似文献   
930.
The Hani Rice Terraces System, based on gravity-flow irrigation, is one of the Globally Important Agricultural Heritage Systems(GIAHS) pilot sites selected by FAO in 2010. The water resource plays an important role in the sustainable development of this system. The value of water conserved by the forest is influenced by natural, economic and social factors. In this paper, the water quality, per capita water resources, per capita GDP and population density are chosen as indices to construct an index system for a comprehensive evaluation of water resources value. The weights of these indices are 0.443, 0.31, 0.141 and 0.106 respectively, which are determined by the analytic hierarchy process(AHP) method. The water resources value has been assessed by the fuzzy comprehensive evaluation model. The results show that the water resources value in the Hani Rice Terraces System is 4.25 RMB/m~3. Evaluating the value of water resources in the Hani Rice Terraces System can provide a reference for ecological compensation, for raising public awareness of the importance of protecting the system, and ultimately achieving its sustainable development.  相似文献   
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