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贻贝隶属于软体动物门(Mollusca)、双壳纲(Bivalvia)、翼形亚纲(Pteriomorphia)、贻贝目(Mytilida)、贻贝超科(Mytiloidea),大约有400种贻贝分布在世界各地,可适应淡水、潮间带至深海多种生境。本实验以贻贝科6亚科12属28种中国沿海常见贻贝的28SrDNA为目的片段,构建系统发育进化树,运用最大似然法和贝叶斯推演法分析了贻贝科的系统发生,并追踪贻贝科物种系统演化历史。结果显示:贻贝亚科Mytilinae、偏顶蛤亚科Modiolinae、石蛏亚科Lithophaginae均非单系群。在属阶元,深海偏顶蛤属Bathymodiolus、贻贝属Mytilus和股贻贝属Perna为单系群。本研究发现应接受将原隔贻贝属Septifer分为Septifer属和Mytilisepta属的分类提议;应接受将原石蛏属Lithophaga中的膜石蛏亚属Leiosolenus提升至属的地位的分类提议。此外,短齿蛤属Brachidontes的单系性不被支持,刻缘短齿蛤Brachidontessetiger并未与短齿蛤属其他物种在系统发育树上聚拢,亲缘关系较远,为不同属物种,建议恢复刻缘短齿蛤原属名Volsella (Dunker, 1857)。 相似文献
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采用从GenBank下载的翼形亚纲11个总科80个种类的28S部分序列,对翼形亚纲11个总科贝类进行系统发育关系研究。在获得的1252个序列位点中,去除插入缺失位点,变异位点共359个,其中简约位点300个。翼形亚纲各总科内各种间的遗传距离为0.01—0.14,明显小于各总科间的遗传距离(除蚶总科与拟锉蛤总科,双肌蛤总科与襞蛤总科以及两总科与贻贝总科外)。贝叶斯树和最大似然树均支持翼形亚纲为单系群,并将11个总科分为3个聚类簇:聚类簇Ⅰ为珍珠贝总科(Pterioidea)、牡蛎总科(Ostreoidea)和江珧总科(Pinnoidea),聚类簇Ⅱ为贻贝总科(Mytiloidea)、蚶总科(Arcoidea)和拟锉蛤总科(Limopsoidea),聚类簇Ⅲ为襞蛤总科(Plicatuloidea)、不等蛤总科(Anomioidea)、双肌蛤总科(Dimyoidea)、扇贝总科(Pectinoidea)和锉蛤总科(Limoidea)。根据本研究的结果,并结合其他学者提出的分类系统,构建了包括4目11总科的翼形亚纲分类系统。 相似文献
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隔鳃类(Septibranchia)又称孔螂超科(Poromyacea),由孔螂科(Poromyidae)、旋心蛤科(Verticordiidae)和杓蛤科(Cuspidariidae)组成。它们的共同特点是呼吸器官——鳃已经退化,在外套腔中产生了隔膜,隔膜具有一定数量的小孔,呼吸的水流通过这些小孔进入隔膜腔内。鳃的消失也导致食性的改变,多数双壳类以鳃滤取食物,而隔鳃类却都是肉食性者,它们是双壳类在演化上比较特殊的一群。隔鰓类全为海产,在潮间带没有其踪迹,在深水区其种类多、数量大,是双壳类中的主要类群,标本的采集要由调查船进行。本文所鉴定的材料是1957年我国第一艘海洋科学考察船——金星号下水以来,中国科学院海洋研究所在全国海域进行的历次底栖生物调査中所获得。
对中国近海的杓蛤从未有人进行过系统的研究。曾报道Cuspidaria chinensis (张玺、齐钟彦,1960), Cardiomy sinica (徐凤山,1980)产于中国近海,然而我们至今未采到前者的标本。本文记述了14种杓蛤,其中13种在中国近海是首次记录。在这些种中,发现于南海的有7种,东海有9种,其中4种是东海、南海所共有；黄海只发现2种。
杓蛤科,两壳不等,左壳大于右壳,壳的后部通常延伸成喙状。外韧带很弱,内韧带通常附着于铰合部的匙状着带板上,有时有一钙化韧带片附于内韧带上。铰合齿变化较大,但除个别情况外,右壳的后侧齿通常是恒定的。 相似文献
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在1985年进行长江口调查时,采到了数个双壳类标本,经鉴定认为系帮斗蛤科一新种——中华帮斗蛤Pandora(Frenamya)sinica sp. nov.。新种左壳前主齿和中主齿为一横向的隔板相连结。右壳中主齿发达,后主齿短小。模式标本保存于中国科学院海洋研究所内。 相似文献
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波纹巴非蛤胚胎与浮游幼虫的形态发育和生长特性 总被引：1，自引：0，他引：1
摘要：在人工繁育条件下,在显微镜下对波纹巴非蛤胚胎与浮游幼虫的形态进行活体观察和拍摄,并用内置目微尺进行壳长和壳高的测量．首次报道了波纹巴非蛤胚胎与浮游幼虫的形态发育和生长特点,利用图版和文字描述了波纹巴非蛤早期生活史的形态并对其发育生长特点进行初步探讨．波纹巴非蛤的早期形态体现了浅海性种类的特点,“D”形幼虫期的壳长为90．37±1．53I,zm,壳高为71．86±1．09μm;壳顶后期壳长为130．17±1,83μm,壳高为110．24±1．39μm,与其他帘蛤科种类相比明显较小． 相似文献
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帘蛤科一新种——扁平美女蛤Circe(Laevicirce)hongkongensis sp.nov.系于1988年采自香港大潭湾潮下带。新种的主要特征是两壳极扁平,铰合部宽阔,区别于本亚属的其他种。 相似文献
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菲律宾蛤仔(Ruditapesphilippinarum)是重要的海洋经济贝类和海水养殖品种,具有较强的表型可塑性特点,不同地理群体之间存在表型差异。本研究根据实测数据建立了胶州湾与天鹅湖菲律宾蛤仔壳长(SL)与壳高(SH)、壳宽(SW)和活体重(W)的回归方程,定量分析了两个地理群体的形态学差异。由于其近似圆形的形态使得所能测量的外部指标较少,限制了传统形态测量学在其地理群体判别中的应用。本研究提出了将传统形态测量学和广义线性模型(GLM)相结合的方法,建立了判别菲律宾蛤仔地理群体的逻辑斯蒂(Logistic)回归方程。结果表明:菲律宾蛤仔的天鹅湖群体比胶州湾群体具有更高的SH/SL和SW/SL比值,壳形椭圆较圆且隆起程度高,"凸"形明显;基于GLM模型的Logistic回归能够快速准确地判别菲律宾蛤仔的地理群体归属,判别正确率高达94.23%。本研究为双壳类物种地理群体判别提供了新的分析方法和技术手段。 相似文献
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X射线分析显微镜(XGT-2000V, Horiba Co.,Japan,1993年制造)是一种新颖、快速的元素分析仪器,可以用来分析海藻中元素的组成特点。本研究对1997年4,5月在山东省威海市采集的22种海藻进行了研究,测定了海藻的Ⅹ射线荧光光谱(XRF),并根据Ⅹ射线特性荧光的能量分析海藻的主要元素组成。然后采用基本参数法(FP法)对每种海藻的主要元素进行了半定量分析。研究结果表明,Ⅹ射线分析显微镜可以快速观测海藻中的主要元素如钾、硫、钙、铁、锌、溴、锶等,是研究元素组成与化学种态的有效的非破坏分析手段。从Ⅹ射线荧光光谱可以看出,绿藻的特征元素是钾、钙、硫,孔石莼(Ulva pertusa)含有较多的铁元素,而浒苔则含有较多的溴元素。褐藻的特征元素除钾、钙、硫之外,还含有较多的锶元素。另外,酸藻 (Desmarestia viridis)含有大量的硫及溴元素,鼠尾藻(Sargassum thunbergii)、单条髓藻(Myelophycus simplex)及酸藻 (Desmarestia viridis)中尚含有较多的铁元素。红藻的特征是多种红藻均含有较大量的溴元素,例如波登仙菜(Ceramium kondai)、松节藻(Rhodomela confervoides)、多管藻(Polysiphonia urceolata)、石花菜(Gelidium amansii)及亮管藻(Hyalosiphonia caespitosa)。另外,珊瑚藻(Corallina pilulifera)中含有大量的钙质。 相似文献
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《African Journal of Marine Science》2013,35(1):67-84
The northern Benguela stock of sardine Sardinops sagax used to be considered one of the major clupeoid stocks of the world; it supported an average annual catch of >700 000 tons throughout the 1960s. The stock has been in a depressed state for more than two decades, as demonstrated by annual catches that averaged around 50 000 tons between 1978 and 1989 and only slightly more in the 1990s. It has experienced fluctuations in abundance of several orders of magnitude during the most recent decade. Population size increased until 1992, when the acoustic estimate of biomass was about 750 000 tons. Catches increased accordingly, averaging 100 000 tons between 1992 and 1995, but from 1992 to 1996 the stock was in decline and the lowest annual catch in the history of the fishery was taken in 1996. Although there was a small increase during the last three years of the decade, the stock remains seriously depleted. Survey-based recruitment indices suggest that the changes in the 1990s were initiated by fluctuations in recruitment, but the decline was almost certainly exacerbated by continued fishing. Poor recruitment and decreasing catch rates between 1993 and 1996 in a number of other key resources suggest that system-wide environmental changes were an important factor in the decline of the sardine stock at that time. Anomalous oceanographic conditions, such as extensive hypoxic shelf waters in 1993/94 and a Benguela Niño in 1995, support this conclusion. 相似文献
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A three-dimensional finite-difference hydrodynamic model has been developed using σ-coordinate for the vertical dimension. An explicit scheme for temporal integration and a staggered grid for spatial discretization have been adopted. The model has been tested against analytical or literature cases for wind and tide induced circulation. Results are in good agreement both with analytical solutions under idealised conditions and with results from the model of Shankar et al. (1996). 相似文献
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The influence of solar activity on the Earth’s global surface temperature (GST) was quantified. The method for estimation of the Granger causality was used, with analysis of the improvement of the prediction of one process by using data from another process as compared to autoprediction. Two versions of reconstructions of the solar flux variations associated with solar activity were used, according to Hoyt et al. [1997] for 1680–1992 (data H) and according to Lean et al. [2005] for 1610–2005 (data L). In general, the estimation results for the two reconstructions are reasonably well consistent. A significant influence of solar activity on GST with a positive sign was found for two periods, from the late 19th century to the late 1930s and from the latter half of the 1940s to the early 1990s, with no inertia or time delay. In these periods, up to 8 and 25% of the variance of the GST change, respectively, can be attributed to solar activity variations. The solar influence increased in the 1980s to the early 1990s according to data H and began to decrease in the latter half of the 1980s according to data L. 相似文献
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《Journal of Sea Research》2007,57(1):65-77
Long-term (1965–2000) changes of macrozoobenthos and hydrography have been studied in the Gulf of Finland (GoF). For the first time, statistical multivariate time series analysis is applied to Baltic Sea data to verify the relationship between biota and interacting environmental factors causing large-scale hypoxia in the open sea. For macrozoobenthos, a consistent long-term development of the assemblages was found over the study area. In the period before the 1990s, very sparse macrozoobenthos prevailed, followed by a notable expansion of macrofauna between the late 1980s and early 1990s and leading to a maximum of total abundance and species number between 1991 and 1996. After that, a sudden collapse of the communities took place in 1996–1997. The hydrographical changes included a continuous decrease in salinity and density stratification until the early 1990s, after which an increase took place again. In contrast, low mean and minimum dissolved oxygen concentrations were observed at the beginning of the study period, followed by increasing values in the late 1980s and early 1990s, and a simultaneous decline of oxygen conditions in 1996. Based on non-linear trends estimated by dynamic factor analysis (DFA), high and significant correlations were found between total macrofauna abundance, number of species, salinity, oxygen conditions, strength of stratification and freshwater run-off. The results confirm that oxygen is obviously a fundamental factor that determines the state of the macrozoobenthos in the deep GoF, overruling other abiotic factors. However, the improvement of the oxygen conditions is apparently caused by the long-term decrease of salinity and loss of stratification in the relatively shallow GoF, reflecting large-scale changes in hydrography of the Baltic Sea during the long 1977–1993 stagnation period. Thus the development in GoF is opposite to the deeper basins in the central Baltic. We conclude that salinity and stratification are probably linked with climatic variability via freshwater run-off, which may be important in regulating the oxygen conditions and state of macrozoobenthos in GoF. 相似文献
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根据我国渤海区域星载微波遥感ＤＭＳＰＳＳＭ／Ｉ１９９４～１９９６年的观察数据的研究,指出现有的星载微波遥感海冰的数据标定和验证ＴＢＩ和ＯＳＩ算法是不适用的。用２２和８５ＧＨｚ的散射指数ＳＩ和１９ＧＨｚ的极化指数ＰＩ,讨论了渤海区域海冰的主要辐射特征,用矢量辐射传输理论数值模拟了ＳＩ、ＰＩ与海冰覆盖及其厚度变化的定量关系,用ＳＩ－ＰＩ图规划了渤海区域性海冰的识别方法,给出了渤海海冰的空间分布及其辐射特征的时间序列变化。 相似文献
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伊豆海脊两侧顺时针流涡的若干观测证据 总被引：1，自引：0，他引：1
本文对方国洪等（１９９５）有关“西北太平洋环流三维结构的计算结果中显示出当黑潮越过伊豆海脊时，由于海脊的阻塞作用，在伊豆海省两侧出现两个顺时针流涡”的论术，提出若干观测和文献的证据，证实这两个流涡是存在的；还对这些流涡的机理作了初步的分析。 相似文献
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《Deep Sea Research Part II: Topical Studies in Oceanography》1999,46(6-7):1275-1300
The Odden ice tongue developed prominently during the winter of 1992–1993, but did not appear at all during the two subsequent winters of the ESOP period. During 1992–1993 the in situ sea-ice characteristics within Odden were studied on four occasions. In addition to direct observation and aerial photography, the measurement programme included retrieval and on-board analysis of frazil- and pancake-ice samples; wave measurements within Odden; and near-surface CTD measurements to examine the effect of melt on the upper ocean (reported in Brandon and Wadhams, 1999. The near surface hydrography beneath the Odden ice tongue, Deep-Sea Research, in press). This paper reports on the characteristics of the frazil- and pancake-ice observed and sampled during this season, expanding on early results (reported in Wadhams et al., 1996 Journal of Geographical Research 101(C8), 18 213–18 235). By combining the results of in situ sampling with the analysis of passive microwave and SAR data of the sea-ice extent through the winter, it was possible to estimate the salt flux into the ocean originating from brine release from sea ice during the growth phases of Odden. 相似文献