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211.
During the period August 1985 to May 1986, phytoplankton in the southern Taiwan Strait was collected and studied for distributional variability in relation to hydrography. The results indicated that maximum standing crops of phytoplankton occurred in October and May due to the outgrowth of certain species of diatoms and blue-green algae. The majority of phytoplankton appeared in the water in the top 25 m and occurred in distinct clusters under the influence of water movement. Multivariate analysis indicated that hydrographic parameters, which accounted for the variability of phytoplankton distribution, varied seasonally. Vertical, spatial and temporal variabilities were also apparent. The close relationship between hydrography and algal distribution justifies the use of variations in the phytoplankton population as a useful tracer of water movement. 相似文献
212.
Noriaki Kimura 《Journal of Oceanography》2007,63(4):685-694
This paper examines the mechanism controlling the short time-scale variation of sea ice cover over the Southern Ocean. Sea
ice concentration and ice velocity datasets derived from images of the Defense Meteorological Satellite Program (DMSP) Special
Sensor Microwave Imager (SSM/I) are employed to reveal this mechanism. The contribution of both dynamic and thermodynamic
processes to the change in ice edge location is examined by comparing the meridional velocity of ice edge displacement and
sea ice drift. In the winter expansion phase, the thermodynamic process of new ice production off the ice edge plays an important
role in daily advances of ice cover, whereas daily retreats are mostly due to southward ice drift. On the other hand, both
advance and retreat of ice edges in the spring contraction phase are mostly caused by the dynamic process of the ice drift.
Based on the above mechanism and the linear relation between the degree of ice production at the ice edge and northward wind
speed, the seasonal advance of ice cover can be roughly reproduced using the meridional velocity of ice drift at the ice edge. 相似文献
213.
Two distinct series of slumps deform the upper part of the sedimentary sequence along the continental margin of the Levant.
One series is found along the base of the continental slope, where it overlies the disrupted eastern edge of the Messinian
evaporites. The second series of slumps transects the continental margin from the shelf break to the Levant Basin. It seemed
that the two series were triggered by two unrelated, though contemporaneous, processes. The shore-parallel slumps were initiated
by basinwards flow of the Messinian salt, that carried along the overlying Plio-Quaternary sediments. Seawater that percolated
along the detachment faults dissolved the underlying salt to form distinctly disrupted structures. The slope-normal slumps
are located on top of large canyons that cut into the pre-Messinian sedimentary rocks. A layer of salt is found in the canyons,
and the Plio-Quaternary sediments were deposited on that layer. The slumps are bounded by large, NW-trending faults where
post-Messinian faulted offset was measured. We presume that the flow of the salt in the canyons also drives the slope-normal
slumps. Thus thin-skinned halokynetic processes generated the composite post-Tortonian structural patterns of the Levant margin.
The Phoenician Structures are a prime example of the collapse of a distal continental margin due to the dissolution of a massive
salt layer. 相似文献
214.
Species composition and distribution of marine nematode community in the North Taiwan Strait 总被引:9,自引:4,他引:9
Cai Lizhe Hong Huasheng Zou Chaozhong Fang Shaohu L Xiaomei Zhang Yueping 《海洋学报(英文版)》2001,20(2):221-229
I~IOW~ne nelnatode is a ban gIOup of benthic OrgAnsrns. Abbot 5 000 spotes Of free-livingnelnatedes have ben dedbo so far, and it has ho estimated that abbot 20 (XX) are as yetunknoWn. Chinese bothologist has Paid attention to marine nelnatodes in China seas in yare. The spatial distribution and shoes commotion of marine nelnatedes in the HUanghe EstUary, Qinhuangdao waters, QingdaO Bay and Xiamen ~ have ho reported (Zhang etal., 1990, 1991, 1993; ac and Li, 1998). ~ new shoes in the… 相似文献
215.
台湾岛的雨量受台湾山地的雨影效应影响明显,各地各月随着风向的不同,雨量表现出很大的差异。福建沿海一线存在着一个雨量低值区,主要是由于该地带所处的地理位置及地形条件所决定,与台湾山地的雨影效应无关。 相似文献
217.
The impact of several chemical poisons on the Arca granosa absorbing 45Ca was studied. The results showed that the absorption of 45Ca in the blood and the soft tissue by Arca granosa was inhibited by the inorganic compounds of Cu, Zn, Pd, Cd, Hg and so on, among which the inhibition of Cd was the strongest, next was that of Cu and Hg. But the inhibition of the absorption of 45Ca in the shell of Arca granosa was little. The impact of three kinds of energy metabolism inhibitory substances on the absorption of 45Ca by the Area granosa showed that the absorption was an active transfer process. 相似文献
218.
河口只是河流与海洋之间的一小部分水域,但对人类社会的发展和生物的进化起着重要的作用。它不仅是生物种群繁殖、育幼和栖息的场所,而且是溯河和降海鱼类洄游的必经之路,因此,河口对生物种群的繁衍延续和资源补充,以及保持生态平衡具有十分重要的意义。
然而,河口又是生态环境十分脆弱和敏感的水域,同时也是受人类干扰最为严重的区域。因此,河口的生态环境问题愈来愈引起人们的关注,其中包括长江三峡水库的兴建对长江口及其附近海域生态、环境的影响,特别是对位于河口两侧的我国著名两大渔场——舟山渔场和吕四渔场的影响问题。影响渔业资源的因子是多方面而且错综复杂的。本文主要通过长江径流的变化与环境因子变量的相关分析,并根据三峡水库不同蓄水方案,对河口近海渔业的影响问题进行初步探讨。 相似文献
219.
Mark R. Jury Bohua Huang 《Deep Sea Research Part I: Oceanographic Research Papers》2004,51(12):2123-2136
We analyze the time-longitude structure of composite cases from model-assimilated ocean data in the period 1958–1998, following on from earlier work by Huang and Kinter (J. Geophys. Res. 107(C11) (2002) 3199) that studied east–west thermocline variability in the Indian Ocean. Our analysis focuses on the Rossby wave signal along the thermocline ridge in the tropical SW Indian Ocean (10°S, 60–80°E), where wind stress curl is important. Anomalous winds in the equatorial east Indian Ocean force successive Rossby waves westward at speeds of 0.1 m s−1±30%. With a wavelength of 7000 km, the period of oscillation is in the range 1.9–5.2 years. The Indian Ocean Rossby wave is partially resonant with the global influence of the El Nino–Southern Oscillation, except during quasi-biennial rhythm. The presence of the Rossby wave offers potential predictability for east–west atmospheric circulation systems and climate that affect resources in countries surrounding the Indian Ocean. 相似文献
220.
Practical implementation of Hilbert-Huang Transform algorithm 总被引:12,自引:0,他引:12
Hilbert-Huang Transform (HHT) is a newly developed powerful method for nonlinear and non-stationary time series analysis. The empirical mode decomposition is the key part of HHT, while its algorithm was protected by NASA as a US patent, which limits the wide application among the scientific community. Two approaches, mirror periodic and extrema extending methods, have been developed for handling the end effects of empirical mode decomposition. The implementation of the HHT is realized in detail to widen the application. The detailed comparison of the results from two methods with that from Huang et al. (1998, 1999), and the comparison between two methods are presented. Generally, both methods reproduce faithful results as those of Huang et al. For mirror periodic method (MPM), the data are extended once forever. Ideally, it is a way for handling the end effects of the HHT, especially for the signal that has symmetric waveform. The extrema extending method (EEM) behaves as good as MPM, and it is better t 相似文献