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LIN Rongcheng HUANG Dingyong GUO Yuqing CHANG Yu CAO Yinkun WANG Jianjia 《海洋学报(英文版)》2014,33(6):90-94
The metazoan meiofauna in the Chukchi Sea were collected from seven shallow water stations(depths ranging 46 to 52 m) and five deep sea stations(depths ranging between 393 and 2 300 m) during the 4th Chinese National Arctic Research Expedition in 2010. The results showed that abundance of meiofauna was higher in shallow water sediments(average of 2 445 ind./(10 cm2)) than in deep sea sediments(407.06 ind./(10 cm2)). A UNIANOVA test for difference between the two different regions was highly significant(F=101.15, p0.01). Nematodes were numerically dominant, representing(96.6±4.6)% of the total meiofaunal abundance at the shallow water stations and(98.90±1.42)% at deep sea stations. The number of higher taxonomic groups and abundance of meiofauna were higher at Stas CC1, CC4, and R06 near the Bering Strait and the continent, than at the rest of the shallow water and deep sea stations. The primary factors causing the differences were concentrations of nutrients P and Si of bottom seawater(R=0.831, p0.003), followed by depth(R=-0.655, p0.05) and sand fractions of sediments(R=0.632, p 0.05). The numbers of meiofauna on the 65 μm and 32 μm sieves were significantly higher than those on the rest of the screens. Differences in numbers of meiofauna retained on screens with different mesh openings were highly significant among all sampling stations(F=31.60, p0.01). The highest numbers of individuals on screens with 32 μm mesh openings were found at deep sea stations. The number of meiofauna in the top 0–1, 1–2, and 2–4 cm segments constituted 84.4% of the total and was significantly higher than those in the bottom 4–6 and 6–10 cm segments(F=15, p0.01). 相似文献
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人类自有生以来,就跟水体发生了难以舍弃的密切关系,甚至在建立最高级的政治地理实体——国家之际,还会根据水体来命名国家.这种国名可分为两类,一类是据河流命名的国名,另一类是据湖泊命名的国名.世界上的湖泊千干万万,但根据湖泊命名的国名却全部集中在非洲,这些国名是乍得、马拉维与坦桑尼亚.乍得据以命名的湖泊是乍得湖（Lac Chad）.乍得共和国深处非洲大陆腹地,乍得湖的大部位于它的西部.“乍得”一词,在当地语言中是“大片的水”的意思.乍得湖的湖面随雨季和旱季而变换,湖面扩大时（11～12月）可达2.2万平方公里（约等于我国青海湖的5倍）,湖面缩小时（6～7月）也超过1万平方公里.在赤道以北的大半个非洲,乍得湖是首屈一指的大湖;而以整个非洲大陆而论,它的面积也仅次于维多利亚湖、坦噶尼喀湖和马拉维湖而居第四.乍得湖原来的“体躯”更大,距今1万年前差不多与亚欧大陆的里海相当,后来才逐渐缩小.乍得湖面积虽大,深度却很浅,通常在4～7米之间.从横断面上看,乍得湖很像一个盛满水的大浅盘子. 相似文献
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广袤的非洲大陆呈南北走向,有着漫长的海岸线,东临印度洋,西濒大西洋,最南端的好望角是连接印度洋和大西洋的关键海上通道,战略地位十分重要。在21世纪非洲大陆经济日益融入全球经济一体化运作的今天,非洲石油、钻石、木材、有色金属等重要战略性矿产资源出口激增,争夺并控制非洲大陆濒海区域、好望角咽喉要道、东西两翼的印度洋和大西洋上的海运航线,就有着异乎寻常的地缘 相似文献
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<正>天上有流动的云云边有游荡的鹰炙热的海水吞吐着轻烟沙滩拥抱着岩石厮守了一百万年的光阴丛林深处有黑色的旋律在月光下幻变距离太阳最近的土地灵魂寄居的非洲草原这里没有历史这里就是历史去南非之前,非洲只是照片和荧屏上的一些静止图像。去南非之后,非洲的景象印在了脑海深处,就像一部生动的电影,在每一个乏味的夜晚循环上映,反复撩拨着内心那一根麻痹已久的、渴盼自由与飞翔的感性神经。 相似文献
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