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991.
992.
黄海冷水团海域微型异养鞭毛虫对异养细菌和蓝细菌摄食作用的初步研究 总被引:2,自引:1,他引:1
2006年10月在黄海冷水团海域的三个站点开展了微型异养鞭毛虫、异养细菌和蓝细菌的密度和生物量调查,进行了微型异养鞭毛虫的现场摄食实验,通过荧光标记细菌法和消化系数法获得该海区微型异养鞭毛虫对异养细菌和蓝细菌的摄食率,并估算了微型异养鞭毛虫对异养细菌和蓝细菌现存量及生产力的摄食压。结果显示,微型异养鞭毛虫、异养细菌和蓝细菌的密度分别为0.36×103~1.13×103,0.39×106~1.13×106和0.04×104~3.74×104cells/cm3,温跃层以上明显高于底层。微型异养鞭毛虫对异养细菌的摄食率为5.33~14.89个/(HF·h),对蓝细菌的摄食率为0.26×102~23.10×10-2cells/(HF·h),摄食率随深度而下降。微型异养鞭毛虫每天能消耗9.27%~33.08%的异养细菌现存量和8.12%~16.09%的蓝细菌现存量。同时,微型异养鞭毛虫对异养细菌和蓝细菌的日摄食量各占它们生产力的2.66%~13.10%和8.12%~16.09%。研究表明微型异养鞭毛虫的摄食可能不是秋季黄海冷水团海域浮游细菌及其生产力的主归宿。 相似文献
993.
南海西缘断裂带右行走滑的地球动力学机制 总被引:3,自引:0,他引:3
南海西缘断裂带,北端始于17°30'N附近的海南岛南部,往南延伸止于北西走向的卢帕尔断裂,南北延伸长度约达1 600 km,十分壮观(见图1)。该断裂带除了其名称和延伸长度在不同研究者的文章中各有所不同[1—4]之外,其名称和作用至少在20世纪80年代初已得到广泛的应用,早已成习惯,如在《亚洲地质》[5]一书和杨树康等[1]、陈国达[4]等许多著名科学家的论著中不断地得到了应用。该断裂带的构造地位和作用得到地学界的普遍重视,到目前为止地学界基本上认为它就是印支亚板块与南海亚板块之间的区域性边界断裂。 相似文献
994.
卫星高度计实现了对全球性或区域性的海洋参量的实时监测,TOPEX卫星高度计提供了迄今为止时间序列最长、数据质量最高的全球海面风速和有效波高的同步观测资料。利用TOPEX卫星高度计资料,分析了有效波高4m以上的巨浪在台湾岛周边海域的时空分布特征,结果表明台湾岛周边海域巨浪的分布具有明显的季节特征。每年平均有效波高最大值大多数出现在夏季,春季是1a中有效波高最小的季节,而秋季和冬季是巨浪出现频率最高的季节。波高大于6m的巨浪大都出现在台湾岛东部及东北部海域,在南部海域出现较少。 相似文献
995.
On tectonic movement in the South China Sea during the Cenozoic 总被引:1,自引:1,他引:0
The tectonic movement taking place at the end of Cretaceous and the beginning of Cenozoic had opened the Cenozoic phase of polycyclic tectonic movements, then the whole crust of the South China Sea had been mainly subjected to the regional stress field of tectonic tension, which was characterized by rifting depression. Seven times of regional tectonic movement and sedimentation had been assembled into a geological development history of polycyclic oscillation. Especially, the tectonic movements were strongly intensified at the end of Cretacious and the beginning of Paleagene, between Late Eocene and MidOligocene, during Mid and Late Miocene. These three times of tectonic movement had built the most important regional tectonic interfaces in the South China Sea. Crust movements of the South China Sea were the result and epitome of interaction of the Eurasia, Pacific and IndoAustralia plates, that is, they were introduced by polycyclic changes of directions, rates and strengths of lithospheric movements and asthenospheric flows across the Pacific and IndoAustralia plates. 相似文献
996.
ZHENG Lianming LIN Yuanshao LI Shaojing CAO Wenqing XU Zhenzu HUANG Jiaqi 《海洋学报(英文版)》2009,28(1):109-115
Aequorea taiwanensis, a new hydrozoan species from the Taiwan Strait was described using morphological and molecular characteristics. Both morphological and mitochondrial cytochrome oxidase subunit I (mtCOI) data supported A. taiwanensis n. sp. as a valid species. Sequence divergence and genetic distance of A. taiwanensis n. sp., A. papillata and A. conica were analysed based on the mtCOI gene sequences. The mtCOI sequences from these three species of the genus Aequorea showed high variation frequency, with sequence divergences ranging from 9.10% to 11.9%, and pairwise genetic distances ranging from 0.097 to 0.130. MtCOI sequence analysis provided diagnostic molecular systematic characteristics for accurate identification and discrimination of the species of Aequorea or their populations, and will be used to resolve evolutionary relationships among them.It was suggested that 10%—20% pairwise mtCOI sequence differences indicated the specieslevel divergence among congeneric species in the Hydromedusae. 相似文献
997.
A class of coupled system of the E1 Ni(n)o/La Ni(n)a-Southern Oscillation (ENSO) mechanism is studied. Using the perturbed theory, the asymptotic expansions of the solution for ENSO model are obtained and the asymptotic behavior of solution for corresponding problem is considered. 相似文献
998.
Distribution characteristics of heavy metals in surface sediments and core sediments of the Shenzhen Bay in Guangdong Province, China 总被引:1,自引:1,他引:0
The concentration of zinc, chromium, cadmium, nickel, lead and copper was measured on both surface sediments and core sediments in the Shenzhen Bay. The average contents of all metals have exceeded the background values in the coastal zone of Guangdong Province. Cadmium is a heavy pollution matter which indicates a strong pollution level according to the ecological risk coefficient method. The ecological risk index of the whole area is 299 which belongs to middle and strong level. The area with strong pollution level is the near shore area closing to the inside of Shenzhen Bay, Shakou area is in the middle level while the weak pollution level occurs in Shenzhenhe Estuary according to ecological risk index. The four sediment cores can be divided into two parts based on lead-210 dating, sediments size analysis and economic development period in surrounding areas since 1950 with strong human intervention. The sediment size, deposition rate and human activities have positive relationship with the contents of heavy metals which directly impact the pollution level of heavy metals in sediments in Shenzhen Bay. 相似文献
999.
珠江口盆地珠三坳陷层序地层样式分析 总被引:10,自引:0,他引:10
珠江口盆地珠三坳陷是一个典型的箕状断陷盆地,其层序地层格架受到主干断裂特别是珠三南断裂的强烈控制。由于珠三南断裂活动的差异性,盆地东部、中部和西部表现为不同的格架样式。并据此划分出坳陷内的3种典型层序样式,分别是缓坡型、断控陡坡型和断阶型层序样式。文昌A凹陷与阳江低凸起过渡的斜坡区和文昌B凹陷与琼海低凸起过渡区为具有坡折的缓坡背景,发育缓坡坡折型层序样式,发育斜坡扇、盆底扇、低位楔。珠三南断裂等主干断裂下降盘发育断控陡坡带层序样式,在珠三南断裂中部地区,发育断阶型层序样式。 相似文献
1000.