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131.
Ninteen species of subfamilies Imbricariinae and Cylindromitrinae, family Mitridae, are recorded from the China's seas. Of which, one genus and six species are recorded for the first time from China's seas, i.e., genus Ziba Adams H and Adams A, Cancilla (Cancilla) carnicolor, Ziba duplilirata, Z. insculpta, Neocancilla circula, Scabricola (Scabricola) desetangsii, Scabricola (Swainsonia) ocellata ocellata. 相似文献
132.
1 IntroductionThe family Mitridae mainly distributes in tropicaland subtropical regions, particularly in the Indo—Pa-cific Ocean. Up to date, nearly 500 species have beendescribed in the world (Cernohorsky, 1976, 1991). InChina, the taxomonic and faunal research is very poor.Kuroda (1941) recorded 71 species from Taiwan, Chi-na (22 of them belong to the genus Vexillinae, which isplaced in family Costellariidae now as the species ofthis genus all have prominent axial cords or grooves onthe… 相似文献
133.
With a view to utilize local algae as food organisms in mariculture, the green alga Chlamydomonas plethora and the diatom Nitzschia frustula were isolated and studied from the unique coastal waters arid zone off Kuwait. Batch cultures of C. plethora and N. frustula had maximum division rates (μmax) of 2.5 and 3.4 day?1, respectively. Cultures grown for 36 h yielded comparable growth rates. Photosynthesis‐irradiance relationships in cultures harvested at various phases of growth showed that cultures attained log phase after 1‐day growth and yielded the highest assimilation numbers (P: μg C [μg Chl a]?1 h?1): 22.8 for C. plethora and 18.1 for N. frustula. Their initial slopes (αB: ng C [μg Chl a]?1 h?1 [μmol m?2 s?1]?1 were also the highest observed so far: 79.5 for C. plethora and 39.6 for N. frustula. Photoinhibition was low. Compared with these, assimilation numbers in senescent cultures of 20‐day growth were <8% of the maximum for both species, and the initial slope decreased to 17 and 13% in C. plethora and N. frustula, respectively. Two polyunsaturated fatty acids (20:5n‐3 eicosapentaenoic acid and 22:6n‐3 docosahexaenoic acid) that are essential in many marine animal diets constituted up to 24% and 1.9% of the total fatty acids, respectively. Of the two algae, N. frustula contained higher levels of 16:1n‐7, 20:5n‐3 and comparatively low levels of 22:6n‐3 fatty acids. Due to its rapid growth, high photosynthetic rate and presence of the amino acids leucine, lysine, glutamic acid and arginine N. frustula has good potential as a feed organism in mariculture applications. The capacity of these algae to produce a wide range of size groups (nano and net plankton) is an additional bonus for mariculture operations. 相似文献
134.
Riyad S. Manasrah Fuad A. Al-Horani Mohammad Y. Rasheed Saber A. Al-Rousan Marouf A. Khalaf 《Estuarine, Coastal and Shelf Science》2006,69(3-4):567
This study was focused on analysis of the horizontal and vertical current components with correspondence to tide variation, heat flux, seiches and relative backscatter intensity in coastal waters of the northern Gulf of Aqaba during the summers of 2001–2004. Spectrum analysis has shown eight distinguishable peaks of the tide measurements. In addition to semidiurnal and diurnal barotropic tides, signal periods of 8.13, 5.89–6.32 and 4.06 h were related to shallow water compound and overtides of the principal solar and lunar constituent and to seiches (second and third mode) generated in the Red Sea, whereas seiches of the first mode might enhance the semidiurnal tide signal. The shortest periods of 1.02–1.05, 0.50 and 0.36 h were related to seiches (first, second and third mode, respectively) generated in the Gulf of Aqaba. The spectrum analysis and cross-correlation tests of the horizontal and vertical current components and relative backscatter intensity suggested that the vertical motion at the diurnal period was either due to migration of zooplankton or to water convection. Both of which were of the same order as vertical motion induced by horizontal motions of water particles projected parallel on the bottom gradient line. On the other hand, semidiurnal and diurnal periods detected in the vertical currents were caused by the strong signal in the cross-shore current component, first mode seiches generated from the Red Sea and tide. This could be considered as an indicator of the dominant force influencing the currents, such as winds, thermocline depth, seiches and tidal forcing. A permanent convection during summer is likely to occur in the shallow coastal waters due to relatively high inclined bottom, high evaporation and blowing of dry air, as well as the observed dominance of the downward vertical currents in coastal waters. 相似文献
135.
用卫星遥感手段反演海洋表层悬浮体浓度(Suspended Sediment Concentration,SSC)来研究其分布和输运的方法已经被广泛使用。东中国海属于水文和光学性质较为复杂的二类水体,表层悬浮体浓度的分布规律和水体的固有光学特性时空变化大,增加了遥感研究的难度。在对前人的研究进行比较和总结后发现,根据实测SSC数据对不同区域、不同时间段(季节、潮汐周期)建立分段模型可以提高整体反演精度。在选择参与反演的波段时,河口和近岸等高SSC海域以及远岸低SSC海域有各自不同的最优波段组合。高SSC海域常使用水体反射率第二反射峰、第一反射峰前波段作正比波段组合参与反演,低SSC海域常使用水体反射率第一峰波段作正比、峰前波段作反比参与反演。同时,在反演模型中考虑泥沙粒径的影响可以显著提升反演精度,并且也有可能在浅海区突破现有遥感研究手段的水深限制。目前模型精度评价标准使用较为混乱,平均相对误差、平均绝对误差和均方根误差等可以作为综合精度评价指标,模型的稳定性则可以用误差敏感性分析方法验证。高时空分辨率的海色卫星传感器的出现使得海洋短时间尺度事件的研究成为海色遥感研究的趋势之一。 相似文献
136.
137.
基于1993—2012年TOPEX/Poseidon(T/P)卫星海平面异常SLA(Sea Level Anomaly)数据和FSCR(Climate Forecast System Reanalysis)再分析风场资料,分析黄东海域近20 a海平面的时空分布特征,尤其是不同时间尺度风场影响的变化特征,进而通过区域海洋模式对海面高度短期变化的可能机制进行探讨。结果表明:1)黄东海域海平面多年平均状态为南高北低,近海面季节性风场在岸线分布和海水热膨胀特征下,造成海面冬春季偏低,夏秋季偏高。近20 a黄东海域平均风速逐步减弱,平均海面上升速率为2.9 mm/a。2)风场的短期活动主要为灾害性大风,统计显示冬夏寒潮大风和台风大风均呈频数减少、强度增强的趋势。运用FVCOM(Finite Volume Community Ocean Model)模拟分析台风和寒潮作用下黄东海域海平面的变化,发现台风强风可形成辐散式海流气旋式涡旋,对应海面为下凹负值中心;北路寒潮大风可形成海流反气旋式涡旋,对应海面为上凸正值中心。两类涡旋的强海流部分增强了海面倾斜度。3)强海流部分动能和动量迅速向海水深部下传,无论在深度和强度上,寒潮造成的海流涡旋动能和动量下传比台风涡旋更迅速,更强。这与寒潮降温引起的海洋层结不稳定对流作用有关。 相似文献
138.
139.
海域区古近系含煤地层基准面旋回识别与对比:以琼东南盆地为例 总被引:1,自引:0,他引:1
研究了琼东南盆地古近系含煤地层的沉积体系。研究区主要发育冲积扇/扇三角洲-海底扇体系、滨浅湖-中深湖-浊积扇体系、辫状河-辫状河三角洲-水下扇体系、潮坪-泻湖体系、滨浅海-浊积扇体系等沉积体系,其中辫状河-辫状河三角洲-水下扇体系、潮坪-泻湖体系聚煤作用较强。运用高分辨率层序地层学理论与技术方法,进行了中、短期基准面识别与对比。短期基准面对比界面主要类型是冲刷现象及其上覆的滞留沉积物、土壤化沉积与泥炭化事件沉积组合、微相岩相类型或相组合在垂向剖面上转换、测井曲线突变界面等。琼东南盆地古近系的地层中,由不同成因特征的边界所界定的短期基准面旋回主要有向上"变深"的非对称型短周期旋回层序(A型层序)、向上变浅的非对称型短周期旋回层序(B型层序)和向上变深再变浅的对称型短周期旋回层序(C型层序)。 相似文献
140.
The multi-scale characteristics of wave significant height (Hss) in eastern China seas were revealed by multi-scale wavelet analysis. In order to understand the relation between wave and wind, the TOPEX/Poseidon measurements of Hs and wind speed were analyzed. The result showed that Hs and wind speed change in multi-scale at one-, two-month, half-, one- and two-year cycles. But in a larger time scale, the variations in Hs and wind speed are different. Hs has a five-year cycle similar to the cycle of ENSO variation, while the wind speed has no such cycle. In the time domain, the correlation between Hs and ENSO is unclear. 相似文献