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正2012-2-1南设德兰群岛乔治王岛今天,是我们在南极地区考察的最后一天。考察地就是中国长城科考站以及乔治王岛上著名的海豹滩。今天一大早,身穿红色冲锋衣的站长和其他科考站的成员们就已经在码头迎接我们的登陆艇了,可能因为已经在外面等了一会,他们的鼻子都有些发红。我们首先进入的是长城站的生活区。这里好像是一个的朴素的5口之家,但是由于我们这些青少年客人的到来,被装扮得好似过春节一般。"客厅" 相似文献
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Since the ban on the use of organochlorine pesticides (OCPs) such as dichloro-diphenyl-trichloroethane (DDT) and hexachlorocyclohexane(HCH) in agriculture, their levels have generally dropped. In a number of cases, however, the levels of these OCPs were found to be unchanging or even increasing after the ban. With the aim to unveil the possible causes of these exceptions, we collected two lake cores from King George Island, West Antarctica, and determined their accumulation flux profiles and temporal trends of these OCPs. In the lake core sediments with glacier meltwater input, the accumulation flux of DDT shows an abnormal peak around 1980s in addition to the expected one in 1960s. In the lake core sediments without glacier meltwater input, the accumulation flux of DDT shows a gradual decline trend after the peak in 1960s. This striking difference in the DDT flux profiles between the two lake cores is most likely caused by the regional climate warming and the resulted discharge of the DDT stored in the Antarctic ice cap into the lakes in the Antarctic glacier frontier. Furthermore, to investigate the change of OCPs loadings in the Antarctic coastal ecosystem, we reconstructed the HCH and DDT concentration profiles in penguin droppings and observed a gradual increase for the former and a continuous decrease for the latter during the past 50 years. The increase of HCH seems to be due to the regional warming from the early 1970s and the resulted HCH discharge to the coastal ecosystem by glaciers' meltwater and the illegal use of HCH in the Southern Hemisphere in the recent decade. The different temporal trends of HCH and DDT accumulation rate in the lake core with glacier meltwater input and the aged penguin droppings can be explained by their different water-soluble property. 相似文献
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在千里冰封的南极,企鹅顽强地生活 着。冬天,成年企鹅腆着大肚子,摇摇摆摆地来到海边,跳入寒冷刺骨的海水中,捕捉为数不多的食物,然后长途跋涉几十公里,回到冰层深处的家园,用带回的食物哺养刚刚孵出的小宝宝。平常,它们还要提防贼鸥、巨海燕、海豹等天敌的袭击,稍有不慎,灾难就会降临。在如此艰难的环境下,企鹅已经生存了数百万年。然而,在人类出现后,企鹅面对的危险开始变得越来越大了。 今天,人们只有在南极才能见到企鹅,而生物学家通过对古生物化石的研究发现:北半球曾有大量企鹅生活过。从地中海到挪威、… 相似文献
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南极阿德雷岛企鹅(2003和2006采集的两只企鹅机体组织)中检出持久性有机氯污染物(POPs)多氯联苯(PCBs)和有机氯农药(OCPs),分析测定了头颅、脂肪、肌肉、骨质和尾臀腺中的PCBs和OCPs。脂肪和尾臀腺中的有机氯含量比其他组织要高得多,(PCB含量范围为(126.9~277.0)×10-9;HCB为(43.2~197.0)×10-9;ΣHCH为(0~20.7)×10-9;ΣDDT为(79.4~110.1)×10-9。同时测定了企鹅、贼鸥和巨海燕蛋卵中的有机氯残留,结果显示,企鹅卵中检出POPs含量要远低于贼鸥和巨海燕。对卵样的POPs数据进行统计分析发现不同鸟种POPs积累水平的差异取决于不同鸟种的生态习性,如活动范围、迁徙距离、觅食习性等。另外,对海鸟栖息地粪土样进行的研究发现POPs含量随着不同海鸟的食谱宽窄和巢址选择的不同而变化。 相似文献