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71.
Pseudopleuronectes yokamae (Günther) is one of the most important economic fish species in the genus living specially in the northwest Pacific, and is distributed in the southern area of the far east sea of Russia, Japan, Korea, the Huanghai Sea, the Bohai Sea and the northern area of the East China Sea. Usually they live in nearshore waters of these areas as geographic subpopulations. P. yokamae in the Sheath Bay belongs to a local group of the Huanghai-Bohai Sea subpopulation and is distributed in the mouth and adjacent waters of the bay all the year round, and the catch of its spawning group has important economic value in the area. In this paper the fishery biology features of spawning group of P. yokamae in the Sheath Bay is systematically studied to give biology evidence for proper utilization and the multiplification of its resources.  相似文献   
72.
在采用回收法治理锯条厂氰化物污水中,通过改造生产工艺,减少污水量,提高氰化物浓度及污水经除油后减压蒸馏,可回收50%~90%的氰化铂,其他盐分也可全部回收,从污水中蒸出的蒸馏水能在系统内循环使用。  相似文献   
73.
水槽造流系统水力计算与泵机选择   总被引:1,自引:0,他引:1  
提供一种完整的用于试验水槽造流系统的水力计算和泵机选择方法 ,可用于其他类似工程设计。  相似文献   
74.
海洋数字图书馆建设概论   总被引:1,自引:1,他引:1  
本文在探讨数字图书馆建设关键技术的基础上,从图书馆门户网站、海洋特色数字化资源、海洋文献检索服务系统和图书馆自动化系统建设等方面,概述了海洋数字图书馆建设的实践,以推动海洋图书馆的进一步发展。  相似文献   
75.
As a fundamental study to evaluate the contribution of the Kuroshio to primary production in the East China Sea (ECS), we investigated the seasonal pattern of the intrusion from the Kuroshio onto the continental shelf of the ECS and the behavior of the intruded Kuroshio water, using the RIAM Ocean Model (RIAMOM). The total intruded volume transport across the 200m isobath line was evaluated as 2.74 Sv in winter and 2.47 Sv in summer, while the intruded transport below 80m was estimated to be 1.32 Sv in winter and 1.64 Sv in summer. Passive tracer experiments revealed that the main intrusion from the Kuroshio to the shelf area of the ECS, shallower than 80m, takes place through the lower layer northeast of Taiwan in summer, with a volume transport of 0.19 Sv. Comparative studies show several components affecting the intrusion of the Kuroshio across the 200 m isobath line. The Kuroshio water intruded less onto the shelf compared with a case without consideration of tide-induced bottom friction, especially northeast of Taiwan. The variations of the transport from the Taiwan Strait and the east of Taiwan have considerable effects on the intrusion of the Kuroshio onto the shelf.  相似文献   
76.
The summer distributions of planktonic microbial communities (heterotrophic and phtosynthetic bacteria, phtosynthetic and heterotrophic nanoflagellates, ciliate plankton, and microphytoplankton) were compared between inner and outer areas of Lake Sihwa, divided by an artificial breakwater, located on the western coast of Korea, in September 2003. The semienclosed, inner area was characterized by hyposaline surface water (<17 psu), and by low concentrations of dissolved oxygen (avg. 0.4 mg L1) and high concentrations of inorganic nutrients (nitrogenous nutrients >36 μM, phosphate <4 μM) in the bottom layer. Higher densities of heterotrophic bacteria and nanoflagellates also occurred in the inner area than did in the outer area, while microphytoplankton (mainly diatoms) occurred abundantly in the outer area. A tiny tintinnid ciliate, Tintinnopsis nana, bloomed into more than 106 cells L1 at the surface layer of the inner area, while its abundance was much lower (103-104 cells L1) in the outer area of the breakwater. Ciliate abundance was highly correlated with heterotrophic bacteria (r = 0.886, p < 0.001) and heterotrophic flagellates (r = 0.962, p < 0.001), indicating that rich food availability may have led to theT. nana bloom. These results suggest that the breakwater causes the eutrophic environment in artificial lakes with limited flushing of enriched water and develops into abundant bacteria, nanoflagellates, and ciliates.  相似文献   
77.
普里兹湾陆缘水边界的变化   总被引:10,自引:0,他引:10  
利用1998年11月-1999年2月中国第15次南极考察资料,讨论了普里兹湾附近陆缘水边界(CWB)两侧的水团分布,以及CWB的中心位置、锋面宽度、锋面强度、锋面的垂直深度和垂直厚度等物理特征的空间变化。并与1992年12月-1993年2月中国第9次南极考察资料进行了比较,说明了CWB的时间2变化。同时,还进一步分析了CWB两侧海水运动的各向异性,以及动力高度场的形势,指出了动力高度槽,CWB锋面  相似文献   
78.
The recent benthic meiofaunal foraminiferal assemblage from the continental slope (590-2 003 m) off Cape Hatteras, North Carolina exhibits high species richness and evenness, moderate diversity values, and lacks numerically dominant species. The preserved planktic assemblage has relatively low species richness, high evenness, low diversity, and a few numerically dominant species. Approximately 9% of the benthic species are those that typically live within continental shelf depth ranges. The benthic assemblage abundances and diversities do not follow depth patterns or geophysical characteristics. No biogeographic boundary can be described within the study area for meiofaunal foraminifera. Oxygen limitation does not appear to be a factor affecting the benthos of the North Carolina continental slope based upon the community structure of the benthic foraminifera, if total assemblage is assumed to reflect the recently living community. The high carbonate content of sediments in the area may be explained by foraminiferal tests. Within the study area, the foraminiferal assemblages are uniform, and probably reflect relative consistency of primary environmental variables as well as dynamic downslope transport and high influx of material from the water column in the vicinity where the Gulf Stream and the Western Boundary Undercurrent cross.  相似文献   
79.
针对海上矿石运输,介绍了一种完成定量任务并能使投资费用最少为目标的最优船队组建方法,同时对易变参数进行了灵敏度分析,使决策更加科学化  相似文献   
80.
1975-1976年,中国科学院海洋研究所东海大陆架调查时,在底栖生物采泥取样中获得3个小单売标本;经鉴定,认为是马蹄螺总科(Trochacea)、蝾螺科(Turbinidac)、缩口螺属(Collonia)中的一个新种。标本存中国科学院海洋研究所。  相似文献   
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