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对南极乔治王岛菲尔德斯半岛贼鸥的食性生态进行观测与研究 ,结果表明 ,本区贼鸥的食物结构中 ,自然生态类食物百分组成 ,棕贼鸥 (C .s.lonnbergi)占 63.4% ,灰贼鸥 (C .maccormic ki)占 77.8%。同期 ,取自考察站的人类废弃物中垃圾食物的百分组成分别为 36.6%和 2 2 .3%。贼鸥食性对考察站废弃物有一定的依赖性 ,与本区环境质量下降 ,尤其考察站对废弃物的疏于管理有着直接的关系。由此表明 ,强化南极考察人员环境意识 ,建立封闭式废弃物管理系统 ,对保护南极环境有重要意义 相似文献
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经1985年12月~1987年3月,三年度夏测绘科学考察,在中国南极长城站地区建立了一套完整的、精确的测绘基准系统。它包括大地坐标系统、高程系统和重力参考系统。本文叙述了建立这些基准系统的方法和数学模型,并分析了测量精度。 相似文献
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本文用澳大利亚墨尔本气象中心,苏联南极青年站地面天气图和NOAA-10,NOAA-11极轨卫星云图确定了东南极普里兹湾及其附近海域1990年1—2月份气旋中心位置;讨论了这些气旋的活动特征。分析了实测大风对应的天气系统,天气形势和卫星云图特征,指出普里兹湾沿海存在气旋、锋面以及锋面云和气旋先后相继的影响。锋面及锋面、气旋先后相继影响与500hPa上的强高压脊天气形势、强风与锋面带中纹理非常不均匀区域有密切关系。 相似文献
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EXPERIMENT OF SHORT WAVE COMMUNICATION AND THE INVESTIGATION OF THE PROPAGATION BEARINGS BETWEEN THE GREAT WALL STATION AND XINXIANG
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《极地研究》1990,1(1):67-74
The distance from the Great Wall Station (62.2°S, 58.9°W) to Xinxiang (35.3°N, 113.8°E) is 16981 kin. The path passes through the polar cap absorption region and the auroral absorption zone, and it is across the equator. In this paper firstly the effects of short wave communication and usable time blocks and frequency ranges between the Antarctic Great Wall Station and Xinxiang from December 1985 to March 1986 are introduced. The comparison between the usable frequency ranges with the estimated MUF is made. The upper limit of frequency ranges of communication along the short great circle path basically agrees with the MUF but there is difference between them along the long great circle path. Secondly, the result of the propagation bearings experiment in January to February 1986 is introduced in more detail, The propagation along the great circle path from the Great Wall Station to Xinxiang is the main propagation mode. But the propagation along non great circle paths occurs at times between Great Wa 相似文献
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自1988年11月至1989年3月,对南极乔治王岛的长城湾沿岸水域中的海洋生物和环境因子进行了调查,1988年11月20日在2号站采得的冰芯中部有一层约5cm的棕色层,而1988年11月17日、20日和26日在5号站采得的冰芯样中有二层棕色层。固定冰中叶绿素a浓度范围在2.55~56.8mg/m~3之间,而且大部分含量集中在海冰的中间层中,而不象其它海区如昭和、戴维斯、凯西和麦克默多等站,大部分叶绿素a集中在海冰的底部,造成这种差别的原因、可能是由于海冰的结构和形成过程不同所致。 相似文献
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本文首次报道了菲尔德斯半岛南部邻近海域的水样和生物样石油污染状况。表层水样的测定结果表明 ,调查海域已受到明显的石油污染。在所调查的各站位 ,中国长城站前海湾受油污最轻 ,水样油的浓度略高于中国《海水水质标准》规定的第三类水质最高容许浓度 ,为 5 1 2 .2 5 μg/L;智利站前和海豹湾受油污最重 ,分别达 41 49.2 3 μg/L和 41 6 9.72 μg/L,约比长城站前海水含量高 8倍。几种海洋生物受污染程度不一 ,潮间带生物受油污明显高于鱼类。鉴于调查海域已受到明显的油污染 ,且进入南极水域后消除不易 ,为保护南极生态环境 ,很有必要开展油的净化规律 ,以及石油污染对生态系统影响等的研究。 相似文献
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Studies on the plasma tryptophan and urinary 5-hydroxy-3-indoleacetic acid in expedition members residing in Antarctica
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Studiesontheplasmatryptophanandurinary5┐hydroxy┐3┐indoleaceticacidinexpeditionmembersresidinginAntarcti┐caXuShuhuai(许澍淮)andX... 相似文献
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Mieke Sterken Elie Verleyen Koen Sabbe Griet Terryn Francois Charlet Sébastien Bertrand Xavier Boës Nathalie Fagel Marc De Batist Wim Vyverman 《Journal of Paleolimnology》2008,39(2):219-235
A late Quaternary diatom stratigraphy of Lago Puyehue (40°40′ S, 72°28′ W) was examined in order to infer past limnological and climatic changes in the South-Chilean Lake District. The diatom assemblages were well preserved in a 1,122 cm long, 14C-dated sediment core spanning the last 17,900 years, and were in support of an early deglaciation of Lago Puyehue. The presence of a short cold spell in South Chile, equivalent to the Younger Dryas event in the Northern Hemisphere, the Antarctic Cold Reversal in Antarctica, or the Huelmo-Mascardi event in southern South America, was not clearly evidenced in the diatom data, although some climate instability may have occurred between 13,400 and 11,700 cal. yr. BP, and a relatively long period (between 16,850 and 12,810 cal. yr. BP) with low absolute abundances and biovolumes could be tentatively interpreted as a period of low rainfall and/or temperatures. An increase in the moisture supply to the lake was tentatively inferred at 12,810 cal. yr. BP. After 9,550 cal. yr. BP, inferred stronger and longer persisting summer stratification, may have been the result of the higher temperatures associated with an early-Holocene thermal optimum. The mid-Holocene appeared to be characterized by a decrease in precipitation, culminating around 5,000 cal. yr. BP, and rising again after 3,000 cal. yr. BP, likely associated with a previously documented lowered frequency and amplitude of El Niño events. An increase in precipitation during the late Holocene (3,000 cal. yr. BP–present) might have marked subsequent increased frequency of El Niño occurrences, leading to drier summers and slightly moister winters in the area. 相似文献
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报道了中国第八次南极考察队(长城站)队员赴南极前、居留南极及回国后尿、血浆的去甲肾上腺素(NE)和肾上腺素(E)含量变化,以探讨考察队员在居留南极期间普遍存在生理和心理变化的物质基础。结果表明:考察队员到达长城站2周时尿中NE急剧增高(与赴南极前相比P<0.05),越冬后(居留南极1年2周)NE大幅度下降(与到达2周时相比P<0.001),考察结束回国后NE恢复到赴南极前水平。尿中E含量在到达南极2周时同样显著升高,且增高幅度大于NE(与赴南极前比较P<0.001),越冬后E水平比到达2周时有所降低(P<0.05),回国后E水平没有恢复。提示,儿茶酚胺变化参与综合应激反应过程,E受心理影响大于生理因素。还发现部分考察队员惧怕抽血,故测定尿儿茶酚胺含量更切实可行。经酸化处理的尿样品在短期内温度(室温)对儿茶酚胺含量影响不大,因此,从南极实地取样返回国内检测及进行南极医学方面的研究完全可行。 相似文献
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本文报道了中国第 1 6次南极考察队 (长城站 )队员赴南极前和在南极居留一年二周返回国内后 ,血中甲状腺素和儿茶酚胺含量的变化 ,以探讨考察队员在居留南极期间普遍存在的生理和心理变化的物质基础。 1 6次队 1 0名男性考察队员血样分别用化学发光法检测血清总甲状腺素 (TT3、TT4)和促甲状腺激素 (TSH)的含量 ,用高效液相色谱 -电化学法测定血浆中肾上腺素(E)、去甲肾上腺素 (NE)和多巴胺 (DA)的含量。结果表明 :长城站 1 6次队 1 0名男性考察队员赴南极前和在南极居留一年二周返回国内后相比 ,血清中甲状腺素TT3含量无显著性差异 ,TT4含量有非常显著性降低 (P <0 0 1 ) ,促甲状腺激素TSH含量有非常显著性升高 (P <0 0 1 ) ;血浆中的NE、DA含量无显著性差异 ,E的含量有显著性降低 (P <0 0 5 )。南极特殊环境对考察队员甲状腺功能具有减退作用 ;对肾上腺髓质E在血浆中含量有降低作用 ;甲状腺和肾上腺髓质系统共同参与南极综合应激反应 ,以调节机体与外界的平衡。 相似文献
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在研究南极长城站地区人类活动规模、环境影响及环境质量现状的基础上,探讨了南极环境研究中几个重要概念的内涵及南极环境影响评估的有关理论和方法。提出可将环境影响评估工作分为计算“影响度”和“环境承载力”两个层次;在目前南极环境缺乏环境基准值、环境标准值的情况下,可据环境背景值进行第一层次的评估工作。以长城站地区发电站废气的直接排放为例,运用高斯模式预测了发电站下风向大气环境质量,并计算了影响度,划分出影响区间,提出科学研究和科考管理的相应建议。 相似文献
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在第27次中国南极科学考察度夏期间,针对长城站原地震台受干扰源(如发电栋、冷库)的影响,对台站进行了重新选址工作,并完成了新台站的基建工程(摆坑、电缆布设等),架设了一套宽频带地震仪。对新台站记录的数据进行分析表明新台站运行稳定,背景噪音小,记录的地震事件信噪比高,这为下一步开展相关地震学方面的研究将提供高质量的数据。尽管本次科考地震观测时间短,但是新台站不仅观测到了远震记录,而且观测到了长城站附近地区的近震和疑似冰震的记录。单台定位结果显示4次近震分布基本与南设得兰群岛走向平行,且震源深度由东北向西南逐渐变深。 相似文献
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Although temperature extremes have led to more and more disasters, there are as yet few studies on the extremes and many disagreements on temperature changes in Antarctica. Based on daily minimum, maximum, and mean air temperatures(Tmin, Tmax, Tmean) at Great Wall Station(GW) and Zhongshan Station(ZS), we compared the temperature extremes and revealed a strong warming trend in Tmin, a slight warming trend in Tmean, cooling in Tmax, a decreasing trend in the daily temperature range, and the typical characteristic of coreless winter temperature. There are different seasonal variabilities, with the least in summer. The continentality index and seasonality show that the marine air mass has more effect on GW than ZS. Following the terminology of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change(IPCC AR5), we defined nine indices of temperature extremes, based on the Antarctic geographical environment. Extreme-warm days have decreased, while extreme-warm nights have shown a nonsignificant trend. The number of melting days has increased at GW, while little change at ZS. More importantly, we have found inverse variations in temperature patterns between the two stations, which need further investigation into the dynamics of climate change in Antarctica. 相似文献