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    30 December 1998, Volume 10 Issue 4 Previous Issue    Next Issue

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    STUDY OF THE MSA,nssSO 2- 4 CONCENTRATION AND MSA TO nssSO 2- 4 RATIO IN THE SNOW/ICE AND ATMOSPHERIC AEROSOLS OF THE REGION SURROUNDING WEDDELL SEA
    1998, 10 (4):  4-14. 
    Abstract ( 1722 )   PDF (282KB) ( 1283 )  
    The MSA and nssSO 2- 4 concentration data from the ice cores and from atmospheric aerosols of the region surrounding Weddell Sea have been analyzed by present paper. The results suggest that the high concentration of biogenic sulphur in the snow and ice as well as in the atmosphric aerosols reflects the proximity of the Weddell Sea even though a distinct strength discrepancy exists in the productivity among areas. It seems higher in the middle of Antarctic Peninsula than near the Filchner Ronne ice shelf as evidenced by the snow/ice analysis. Despite factors impacting on the transport and deposition process of biogenic surlphur, the concentration of MSA and nssSO 2- 4 in snow and ice shows a regular spatial distribution: decreasing with the distance from the open sea and the altitude above sea level. Nevertheless, below a certain height, the “altitude effect” is no longer significant. The “displacement” of seasonality for MSA concentration observed in ice cores of the region has been discussed. The “out of phase” pattern in surface layer is attributed to the modification by prevailing meteorological condition to the transport and deposition process; while “relocation” in the deep layers may be caused by migration, a mechanism which is to be further investigated.The comparative study of the atmospheric and snow/ice samples indicates that at high latitude like Weddell Sea the atmospheric signal of SO 2- 4 and MSA could be somewhat muted in the snow. But the seasonal variation in the airborn sulfate and MSA are reasonably well reproduced in the surface snow, for timing and spacial distribution. The very close ratio of MSA to nssSO 2- 4 (or to SO 2- 4) of atmospheric aerosol and snow/ice sample is indicative of weak, if any, fraction between the two species during the scavenging and deposition process. This could serve as the inner reason to explain the relative stable MSA/nssSO 2- 4 ratio, both for atmosphere and snow, an important regional index for the study of marine biogenic sulfur.
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    GEOCHEMICAL CHARACTERISTICS AND ITS CLIMATIC SIGNIFICANCE IN THE BORECORE AB 32 FROM IKROAVIK LAKE IN THE TUNDRA BARROW,ARCTIC ALASKA
    1998, 10 (4):  15-24. 
    Abstract ( 2082 )   PDF (296KB) ( 1269 )  

    Paleoenvironmental record in the AB 32 sediment core from Ikroavik Lake in Barrow,Arctic Alaska was studied with geochemical assemblages,leaching factors and paleotemperature indicators. According to the geochemical characteristics of the borecore AB 32 and 210 Pb dating,climatic and environmental changes in Barrow,Alaska reconstructed are as follows:1) from 1600 to 1735 AD,it was a period of cold and dry; 2) from 1735 to 1830 AD,it was becoming warm and moist; 3) around 1830 AD,it was obviously with a demarcation of geochemical significance;1830-1994 AD,it was continuous more warm and moist,but appeared cold period around 1969-1970 AD. The paleogeochemical characteristics in AB 32 borecore around 1830 AD are similar with those of modern environment in Ikroavik lake and response to climatic and environmental changes reflected in the borecore AB 67 from Elson lagoon.

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    HUMAN IMPACTS ON THE ENVIRONMENT OF FILDES PENINSULA OF KING GEORGE ISLAND,ANTARCTICA
    1998, 10 (4):  25-34. 
    Abstract ( 1998 )   PDF (507KB) ( 1583 )  

    Antarctic environment has some invaluable baseline information for understanding the global changes. The objectives of this study were to investigate the human impacts on the environment of Fildes Peninsula of George Island. Based on the investigation results and the sampling analysis of the environmental elements of Fildes Peninsula, it was shown that there are some artificial radioactive element 137 Cs in the Antarctic environment: the radioactivity of 137 Cs in the surface soil, the surface moss, the fruticose lichen and crustaceous lichen are 6.00  ̄14.80, 25.07, 29.04 and 58.07 Bq/kg separately; the radioactivity of 137 Cs in the surface soil and crustaceous lichen in northern China are 6.4-37.3 and 294-312 Bq/kg separately, i.e. the sequence of 137 Cs activity is as follows: crustaceous lichen>fruticose lichen>surface moss>surface soil.It was shown that the crustaceous lichen is one of the most sensitive monitors for the effect of the long term diffusion of the 137 Cs . The impacts of the activities of Antarctic expedition on the partial environment include: (1)the change of the landscape or the soil material has made the strong freezing thawing processes, which decrease the stability of the ground surface, cause the degradation of the vegetation; (2)the accumulation of solid waste material in the low lying land around lake causes the change of the thermal equilibrium and water equilibrium in the areas, which increases the seasonal fluctuation of the lake level or makes the lake dried up in March or April; (3)during the progresses of building the expedition and the roads, some moss-banks have been damaged. The biomass (esp. lichen ) and the water body in the Antarctic are very susceptible to damage caused by the presence of man. In the surrounding area of the expedition stations, the concentration of Cr, Cu, Ni, Pb and Zn in the lichen and the waters are evidently higher than that of the contrasting area, the organic matter content of the water is also evidently higher than that of the contrasting area. Fildes Peninsula is one of the most crowded areas of expedition stations, at some extent, the environment and terrestrial ecosystem of Fildes Peninsula have been affected by the human activities. The conservation of the environment and ecosystem have been an important aspect of the Antarctic environmental sciences.

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    PRELIMINARY STUDIES ON THE CHARACTERISTICS OF LEPTONYCHOTES WEDDELLIIS SOUND SIGNALS
    1998, 10 (4):  35-44. 
    Abstract ( 1620 )   PDF (402KB) ( 1317 )  

    This paper describes the acoustical behaviours and sound signals of a female Leptonychotes weddellii and its pup in the Fildes Peninsula,Antarctica under different ecologic behaviour. The results obtained by analysing the signals in the laboratory show that their sound signals are mainly composed of a continuous sound signal and a series of pulses. The signal of “ku……” is sounded by the female Leptonychotes weddellii when it was frightened or excited during breast feed. The frequency range is 102Hz-2.3kHz. The spectrum crests in the frequency mainly concentrate on 400Hz and 2kHz respectively. The signal of “mai……” of the pup Leplonychotes weddellii is continuous sound signal when it was separated from its mother. The frequency range is 829Hz-4.4kHz. The spectrum crests in the frequency mainly concentrates on 1.2kHz and 3.5kHz respectively. The signal of “ai……” sounded by the female Leptonychotes weddellii is continuous sound signal in calling its pup,and the frequency range is 486-1190.0Hz. The spectrum crests in the frequency mainly concentrate on 486Hz. The signal of “ai……” sounded by the pup Leptonychotes weddellii is continuous sound signal when it replied to its mother and the frequency range is 614.9-771Hz. The spectrum crest in the frequency mainly concentrates on 663.7Hz. The signal of “jue ke……” was sounded by the female Leptonychotes weddellii in consoling its pup,and the wave shape is of various change characteristics and its frequency range is 466.5Hz-897.9Hz. The spectrum crest in the frequency mainly concentrates on 673.4Hz. The signals of “du er……” sounded by the female Leptonychotes weddellii consist of a series of pulses in which the pulse width is 48ms at the beginning and 11ms at the end. Its interval is 23-28ms,and the frequency range is 861-2098.9Hz. The spectrum crest mainly concentrates on 1.6kHz.

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    PRELIMINARY RESULT OF IMAGING RIOMETER AT ZHONGSHAN STATION,ANTARCTICA
    1998, 10 (4):  45-52. 
    Abstract ( 1786 )   PDF (150KB) ( 1368 )  

    An imaging riometer with 8×8 antenna array was installed successfully at Chinese Zhongshan Station,Antarctica in January 1997.The structure and working principle of the instrument are described. The first set of observation data is analyzed and the QDC are deduced. Preliminary result show that cosmic noise absorption events is very different between night side and magnetic noon during the measurement over Zhongshan Station. In night side,there are often short duration impulsive absorption events with large absorption area in the northern side of the station,stretching in east west direction. In magnetic noon the absorption events is continuous,which last for more than 1 hour and with absorption area strengthen at northern and southern sides and weaken in the middle. It is thought that the absorption is caused by aurora particle precipitation in night side and by other particle precipitation or convection in cusp at magnetic noon.

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    ANALYSIS OF MICROBIAL CONTENTS OF LIVING MATERIALS IN FILDES PENINSULA,ANTARCTICA
    1998, 10 (4):  53-56. 
    Abstract ( 1848 )   PDF (127KB) ( 1281 )  

    The analysis of microbial contents of living materials in Fildes Peninsula,Antarctica was made by using the plating method with five basic culture media during the austral summers from 1993 to 1994. The 33 samples of the surface and inner materials of their bodies collected were marine algae,mosses,lichen,sea worm,little red clam,cap shaped shell,fish,penguin and whale. It was analyzed and compared to the contents of terrigenous. Marine,intestinal,acid fast bacteria and fungi of each category of organisms. The appropriate rise of incubation temperature promoted the multiplication of the microbes rapid and a large number at some degree. It suggests that the low temperature is still an important factor for restricting the microorganisms in Antarctica.

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    THE PHYSICAL PROCESSES IN THE POLAR UPPER ATMOSPHERE AND THE MAGNETOSPHERE IONOSPHERE COUPLING
    1998, 10 (4):  57-67. 
    Abstract ( 1978 )   PDF (544KB) ( 1840 )  

    The observation of phenomena in the polar upper atmosphere has a long history.It is the development of investigation in the field of the ionosphere,geomagnetic field and auroral phenomena in polar region, that extends the scope of geophysical research to extra terrestrial Space and thus introduces a new important subject, the solar wind magnetosphere ionosphere thermosphere coupling for further study. The sounding rockets and satellites have made a great contribution to confirmation of the Coupling mechanism, meanwhile the coherent and incoherent scatter radars, as well as the ionosondes and geomagnetic stations,which locate around all over the world and have observed records in long term, should not be neglected. The distributions and variations of the convection electric field,the region l and region 2 field aligned currents, the ionospheric disturbance current system including the auroral electrojet,and ionospheric conductivity all together compose a self consistent organic whole. The theoretical study and model calculation are very worthy for further understanding the relative importance of each single link in this system and their mutual relation and interaction.

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    CHANGES OF URINE AND PLASMA CATECHOLAMINE OF EXPEDITION MEMBERS IN ANTARCTIC ENVIRONMENT
    1998, 10 (4):  68-72. 
    Abstract ( 1793 )   PDF (349KB) ( 1246 )  

    The changes of urine and plasma catecholamines, norepinephrine(NE) and epinephrine(E), were investigated in 16 Antarctic expedition members(Great Wall Station) under extreme environmental condition by Spectrophotofluorescent and radioenzymatic assay. Samples were taken at different time:(1)before leaving to Antarctica;(2)2 weeks after arrival at Antarctica;(3)1 year and 2 weeks after arrival and (4) after returning back to China.Results showed that a rapid increase of urinary NE in Antarctica (2) decreased significantly at(3),and returned to normal content at(4).The increase of urinary E was greater than that of NE at Antarctica (2),but kept high level at (4). The results indicated that activation of sympathetic system was involved in syndromic stress, especially psychological responses was associated with high E level. In addition, catecholamines were not affected by temperature and determinative time in room temperature during 3 monthes.

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    OBSERVATIONS ON THE SPORE MORPHOLOGY OF FOUR SPECIES MOSSES FROM FILDES PENINSULA,ANTARCTICA
    1998, 10 (4):  73-75. 
    Abstract ( 1767 )   PDF (239KB) ( 1252 )  

    The spore morphology of 4 species of mosses from Fildes Peninsula ,Antarctica are observed by light microscopy and scanning electron microscopy. They are Encalypta patagonia Broth. , Schistidium hyalino cuspitatum B.G.Bell., S.rivulare (Brid.)Podp. and Bartramia Patens Brid. Spore size ranging from 8.4-32.9μm in diameter.P/E ranges from 0.825-0.906.Colour of the mature spore varies from light yellow to yellow brown.Germinal aperture belongs to katalept type.Exine ornamentation are pilate,baculate or tuberculate. The spores of two species ( Bartramia patens collected in Fildes Peninsula and B.pomiformis collected in Hebei,China) are similar in diameter,shape and aperture. But they are different in spore colour and exine ornamentation. It shows character differentiation between two species in Bartramia.

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    THE PRELIMINARY DISCUSSION ABOUT THE RELATION BETWEEN THE ANTARCTIC SYNDROME AND TERRESTRIAL MAGNETIC FIELD
    1998, 10 (4):  76-80. 
    Abstract ( 1674 )   PDF (144KB) ( 1304 )  

    There have been some reports introducing that the members of investigation group in Antarctica have in varying degrees Antarctic syndrome. To explain this phenomenon,this artical reaches a conclusion that the phenomenon is in some degrees due to the environment of regional terrestrial magnetic field of Antarctica comparing both the data of physiology and that of psycology with the variation of terrestrial magnetic field of Antarctica.

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