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Light-induced bird strikes are known to occur when vessels navigate during darkness in icy waters using powerful searchlight. In Southwest Greenland, which is important internationally for wintering seabirds, we collected reports of incidents of bird strikes over 2-3 winters (2006-2009) from navy vessels, cargo vessels and trawlers (total n = 19). Forty-one incidents were reported: mainly close to land (<4 km, 78%), but one as far offshore as 205 km. Up to 88 birds were reported killed in a single incident. All occurred between 5 p.m. and 6 a.m. and significantly more birds were involved when visibility was poor (snow) rather than moderate or good. Among five seabird species reported, the common eider (Somateria mollissima) accounted for 95% of the bird casualties. Based on spatial analyses of data on vessel traffic intensity and common eider density we are able to predict areas with high risk of bird strikes in Southwest Greenland.  相似文献   
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Broo.  FR 刘小雷 《测绘译丛》1992,(5):43-48,F003,F004
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沿拉布拉多北部大陆边缘确定末次冰期极盛期是非常困难的 ,讨论集中于陆源冰川序列的范围和年代以及与滨外海槽和盆地中的沉积序列的相关性上 ,最终没有得出一个统一意见的原因是对陆源和海洋沉积序列的测年非常困难。这里 ,我们试图描述拉布拉多北部陆架区内的冰消期模式 ,并把这种模式与局部的冰消期陆源证据联系在一起 ,所报道的沉积学资料包括一个大的数据库是从一个巨大的活塞岩心(HU87033-015)中收集的。HU87033 -015的声学相(AF)在浅反射地震测线段 ,表面反射层S0上伏于一个薄(<1ms,双程走时)的透…  相似文献   
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Furadan is a carbamate pesticide used widely to combat agricultural pests. However little information is available about the toxicity of furadan in aquatic macroinvertebrates. The in vivo effects of furadan were evaluated in mussels, Perna perna, and oysters, Crassostrea rhizophorae. Glutathione S-transferase (GST), catalase (CAT) and cholinesterase (ChE) activities were measured in the gills of both species exposed to furadan (100 microg/l) for 96 h. No changes were observed in GST activity in the exposed groups. CAT activity was higher (9%) in the oysters exposed to furadan. ChE activity was inhibited by 64 and 35%, respectively, in C. rhizophorae and P. perna exposed to furadan, suggesting that the former is more susceptible to the toxic effects of furadan.  相似文献   
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We report on the complex structure of the red giant branch (RGB) of omega Centauri, based on a new wide-field and wide-color baseline B and I photometry. Our color-magnitude diagram (CMD) shows the presence of multiple populations along this branch; in particular, we discovered an anomalous branch (RGB-a), which appears to be well separated from the bulk of the RGB stars. On the basis of our CMD and from the previous literature, we conclude that (1) these stars, clearly identified as a separate population in our CMD, represent the extreme metal-rich extension (&sqbl0;Ca&solm0;H&sqbr0;>-0.3) of the stellar content of omega Cen and show anomalous abundances of s-process elements (as Ba and Zr) as well; (2) they are physical members of the omega Cen system; (3) they comprise approximately 5% of the stars of the whole system; and (4) this component and the metal intermediate one (-0.4>&sqbl0;Ca&solm0;H&sqbr0;>-1) have been found to share the same spatial distribution, both of them differing significantly from the most metal-poor one (&sqbl0;Ca&solm0;H&sqbr0;<-1). This last piece evidence supports the hypothesis that metal-rich components could belong to an independent (proto?) stellar system captured in the past by omega Cen.  相似文献   
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为了反映测绘业务技术的变化,满足专业人员培养与资格认可的要求以及创造灵活性的工作机会,必须对教育和培训结构进行改革,应当设置一种反映所有业主需求的综合性的行业驱动的动态教育结构取代继续增设反映一种新“手段”的学科,或增添某些新内容来建立一种新学习计划的做法。  相似文献   
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