The transformation of housing and household structures in France and Great Britain     

Bonvalet C  Lelievre E 《International journal of population geography : IJPG》1997,3(3):183-201

"In France and Great Britain, the last 30 years have seen considerable evolution in the housing stock...and in household structure....This article describes the dynamic interaction of processes influencing the evolution of both households and dwellings. In the two countries, the life course of individuals has become more and more complex. This translates into an ever greater variety of housing needs, not only at different stages in family life, but also in relation to growing job insecurity regardless of family situation. At the same time, policies encouraging home-ownership seem to have reached their limits, because of the new demand for rented accommodation. The answer to sociological and economic evolution cannot be found in a ?single' type of housing and tenure status, but rather in a wide range of dwellings and in the development of a more flexible housing market."  相似文献   

In memoriam: James B. Pollack (1938-1994)     

Toon B  Cuzzi J  Sagan C 《Icarus》1995,113(2):227-231

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Contaminant exposure and effects in Baltic ringed and grey seals as assessed by biomarkers   总被引：3，自引：0，他引：3  

Nyman M  Bergknut M  Fant ML  Raunio H  Jestoi M  Bengs C  Murk A  Koistinen J  Bäckman C  Pelkonen O  Tysklind M  Hirvi T  Helle E 《Marine environmental research》2003,55(1):73-99

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   

The South China Sea thermohaline structure and circulation     

Peter C. Chu  Binbing M  Yuchun Chen 《海洋学报(英文版)》2002,21(2):227-261

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   

Laurencia nanhaiense sp.nov.,a new species of the genus Laurencia(Rhodomelaceae,Rhodophyta) from China     

DING Lanping  HUANG Bingxin  XIA Bangmei  TSENG C K 《海洋学报(英文版)》2007,26(5):136-143

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   

Geographic and temporal variations of sulfate aerosols over the Pacific Ocean   总被引：1，自引：0，他引：1  

F. Parungo  C. Nagamoto  B. Kopcewicz  J. Harris  Zhou Mingyu  L&#; Naiping  S. Hoyt 《海洋学报(英文版)》1991,10(1):47-71

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   

亚马孙河及其河口区中颗粒有机碳的来源和运移     

蔡德陵  F.C.陈  J.M.艾德蒙德 《海洋学报》1989,11(4):458-469

本文将碳同位素比值用于研究亚马孙河及其主要支流中颗粒有机碳(POC)的来源,同时也探讨了河流POC向海洋环境的输送,在亚马孙河上游POC的碳同位索值δ13C(-24.5——28.0‰)较之在其中下游的相应值(-27.9——30.1‰)要重一些一般来说,其支流POC的同位素组成要比在亚马孙河主航道中测得的值要轻一些由碳同位素数据证明,亚马孙河主航道中POC的主要来源是陆地物质,而不是河生生物,在亚马孙河口区和淡水舌中观测到POC的同位素组成有很大的变化范围(-17.5——28.4‰),这被认为是河流的POC与海洋的POC在该区域中混合作用的结果.由同位素数据可计算出河流有机碎屑沿平行于河流航道方向向海可搬运至距河口290km处,而沿亚马孙河淡水舌方向在河口西北方向1100km处仍可看到河流POC的稳定同位素信号.  相似文献   

Chukiang (Shiuchow)-A Study in Urban Geography     

C.W.Wen 《地理学报》1948,(1)

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   

Note on The Phosphate Deposits in China     

C.Y.HSIEH  C.H.CHAO 《地质学报》1948,(Z1):79-82

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   

Notes on A Pleistocence Microfauna from Loping, Kiangsi     

C.C.YOUNG 《地质学报》1947

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