Catch per unit effort, foraging efficiency, and parental investment in breeding great cormorants (Phalacrocorax carbo carbo)     

Gremillet  David 《ICES Journal of Marine Science》1997,54(4):635-644

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Spatio-temporal variability of small copepods (especially Oithona plumifera) in shallow nearshore waters off the south coast of South Africa   总被引：1，自引：0，他引：1  

Francesca Porri  Christopher D. McQuaid  William P. Froneman 《Estuarine, Coastal and Shelf Science》2007,72(4):711-720

Although small copepods are one of the main dietary sources for many commercially important fish, their role in the pelagic trophic dynamics has traditionally been underestimated due to the methodology commonly used in plankton sampling. Temporal variation in abundance of adults and nauplii of small copepods (particularly Oithona plumifera) in nearshore waters on the south coast of South Africa was investigated fortnightly over 14 months at site (km) and location (100 m) scales. Sampling was within <500 m of the shore, where depth was ca. 10 m, using vertical hauls of an 80-μm mesh plankton net from 1 m above the seabed to the surface. Twenty-seven adult copepod taxa were recorded, but Oithona spp. was consistently the most abundant. Taxon richness was 7–19 on each sampling occasion. There was strong temporal variation (Oithona varied between 0 and 2300 m⁻³), but much of this was short-term variability (e.g. between consecutive sampling sessions), with no seasonality or other long-term discernable patterns. There were periods of consistently low numbers, but very high numbers often followed samples with low abundances. Nor was there spatial structure at the location scale, though numbers differed between sites. Despite considerable variability at the location scale within sites, Kenton consistently showed higher densities than High Rocks. Separate analyses, with Bonferroni adjustment, showed that this difference was significant on eight out of 21 occasions for Oithona, six for other pelagic copepods and three for nauplii. This suggests that hydrodynamics favour aggregation of plankton at Kenton. A high degree of short-term variability, with a tendency for aggregation of small zooplankton at certain sites has implications for both pelagic processes and food-web links between the benthic and pelagic environments.  相似文献   

Effect of native and invasive cordgrass on Macoma petalum density, growth, and isotopic signatures   总被引：1，自引：0，他引：1  

Elizabeth D. Brusati  Edwin D. Grosholz 《Estuarine, Coastal and Shelf Science》2007,71(3-4):517-522

Ecosystem engineers can influence community and ecosystem dynamics by controlling resources, modifying the flow of energy or biomass, or changing physical characteristics of the habitat. Invasive hybrid cordgrass (Spartina alterniflora × Spartina foliosa) is an ecosystem engineer in salt marshes in San Francisco Bay, California, U.S.A. that raises intertidal elevations and may be either increasing C₄ plant carbon input into food webs or tying up carbon in a form that is not usable by consumers. A manipulative experiment compared abundance, growth, and stable isotope (δ¹³C and δ¹⁵N) composition of the clam Macoma petalum (=M. balthica) among native marsh, hybrid Spartina, and mudflats in central San Francisco Bay. We found higher densities (individuals m⁻²) of M. petalum on mudflats compared to either native or hybrid Spartina (p < 0.001). Macoma petalum shell growth was significantly greater in mudflats than in either vegetation type in 2002 (p = 0.005) but not 2003. Differences in shell growth between native and hybrid Spartina were not significant. Stable isotope results showed differences between habitats in δ¹³C but not δ¹⁵N. Carbon signatures of M. petalum placed in Spartina were much more depleted than the isotopic signature of Spartina. Neither native nor hybrid Spartina appears to be a significant carbon source for M. petalum in San Francisco Bay, and we found no evidence that hybrid Spartina contributes carbon to M. petalum beyond what is provided by S. foliosa, despite the hybrid's much greater biomass. Our results show that loss of mudflat habitat, rather than increased input of C₄ carbon, is the greatest effect of the invasion of hybrid Spartina on M. petalum.  相似文献   

山东沿海海藻抗肿瘤活性的筛选   总被引：28，自引：6，他引：28  

徐年军  范晓  韩丽君  严小军  曾呈奎 《海洋与湖沼》2001,32(4):408-413

于1997年4月和2000年5月对山东沿海海藻进行较系统的采集，对其中39种海藻的96个样品采用高通量方法进行选择性细胞毒筛选，结果表明，小粘膜藻（Leathesia dif-formes)、多管藻（Polysiphonia urcedata)、萱cytosiphon lomentarius)、海萝（Gloiopeliis fur-cata)、叉开网翼藻（Dictyopteris diuaricata)、点叶菜（Punctaria latifolia)等对KB细胞或HT-29细胞具有选择性抑制活性。局醇、氯仿的提取效率较高，多管藻的乙醇、氯仿提取物，萱藻的乙醇提取物和叉开网翼藻的正己烷提取物都有强的选择性细胞毒活性。  相似文献   

浙、闽海域仙菜科[CERAMIACEAE(RHODOPHYTA)]海藻研究Ⅰ     

刘剑华 《中国海洋大学学报(自然科学版)》1996,(1)

根据1957～1987年期间采自浙江和福建沿岸的仙菜科海藻标本，初步鉴定有7属14种。分两次报道，首先报道其中的5屑7种：复羽多孢藻Pleonosporiumvenustissimum、日本对丝藻Antithamnionnipponicum和卡洛绢丝藻Callithamnioncallophyllidicola为我国首次较全面描述和绘图记录；赫勒对丝藻Antithamnionhubbsii为浙、闽海域首次报道；而如下三个种纵胞藻Centrocerasclavulatum、日本凋毛藻Griffithsiajaponica和对公藻Antithammioncruciatum在浙、闽海区早有报道。  相似文献   

An altered carrying capacity of the Benguela upwelling ecosystem for African penguins (Spheniscus demersus)     

Crawford  Robert J. M.; Underhill  Les G.; Upfold  Leshia; Dyer  Bruce M. 《ICES Journal of Marine Science》2007,64(3):570-576

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食用海藻对肠道菌群及肠道微环境影响的研究   总被引：2，自引：0，他引：2  

吕琴  姜乃澄 《海洋学研究》2002,20(2):58-64

综述了食用海藻对大鼠盲肠肠道菌群及肠道微环境的影响。大鼠喂食添加紫菜等 9种食用海藻的饲料后 ,均能对其盲肠微生物区系及代谢产物和血清脂质水平产生不同的影响 :使肠道中的双歧杆菌数量增加 ,p H值降低 ;抑制血清甘油三酯及血清游离脂肪酸含量。从而改善肠内的生态环境  相似文献   

南海294站柱状沉积孢粉、藻类研究及古环境意义     

张玉兰  贾丽  孙煜华  郑玉龙 《海洋学研究》2003,21(1):5-12

通过对南海294站深海柱状剖面孢粉、藻类的研究,将294站从下至上划分为7个孢粉组合带: 带为Dacrydium-Pinus-Lithocarpus-Quercus(常绿)-Cyathea-Polypodiaceae; 带为Castanopsis-Lithocarpus-Dacrydium-Quercus(常绿)-Pinus-Polypodiaceae; 带为Quercus(常绿)-Castanopsis-Podocarpus-Cyathea-Polypodiaceae; 带为Polypodiaceae-Cyathea-Pteris-Pinus-Gramineae; 带为Quercus(常绿)-Podocarpus-Lithocarpus-Pinus-Cyathea-Polypodi-aceae; 带为Pinus-Quercus(常绿)-Palmae-Mangrovepollen-Gramineae; 带为Dacrydium-Palmae-Mangrovepollen-Pinus-Cyperaceae-Cyathea。相应恢复了南海东部地区12万年以来5个植被、气候演替阶段,依次为:炎热、湿润的热带季雨林—暖热而稍干的热带北缘半常绿季雨林—炎热、湿润的热带季雨林—暖热而稍干的热带北缘半常绿季雨林—炎热、湿润的热带季雨林。结合氧同位素测年资料,对南海294站柱状剖面地层时代划分进行了讨论。  相似文献   

Trophodynamics of the two scyphozoan jellyfishes, Aurelia aurita and Cyanea capillata, in western Norway   总被引：1，自引：0，他引：1  

Bamstedt  Ulf; Martinussen  M. B.; Matsakis  S. 《ICES Journal of Marine Science》1994,51(4):369-382

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多管藻内生真菌Chaetomium globosum.苯甲醛类次生代谢成分研究     

王松  张翼  李晓明  王斌贵 《海洋与湖沼》2007,38(2):131-135

从采自青岛近海的红藻多管藻(Polysiphonia urceolata)中分离到一株毛壳霉属真菌球毛壳菌(Chaetomium globosum.),对其发酵代谢产物的化学成分进行了研究。采用溶剂提取、分配,硅胶柱层析、葡聚糖凝胶柱层析以及制备薄层层析等技术已分离获得6个单体化合物,通过一维、二维超导核磁共振技术、质谱技术等鉴定了其中4个化合物的结构,均为苯甲醛类衍生物,分别为2-(1-庚烯基)-3、6-二羟基-5-(3-甲基-2-丁烯基)苯甲醛(Ⅰ)、2-庚基-3、6-二羟基-5-(3-甲基-2-丁烯基)苯甲醛(Ⅱ)、2-(3、5-庚二烯基)-3、6-二羟基-5-(3-甲基-2-丁烯基)苯甲醛(Ⅲ)、2-(1、3、5-庚三烯基)-3、6-二羟基-5-(3-甲基-2-丁烯基)苯甲醛(Ⅳ)。  相似文献