Impact of Two "El Niño" Events of Different Intensity on the Hypoxic Soft Bottom Macrobenthos off the Central Peruvian wast     

Juan  Tarazona  Wolf E.  Arntz Elba  Canahuire 《Marine Ecology》1996,17(1-3):425-446

Abstract. Monthly changes in the community structure of hypoxic soft-bottom macrobenthos have been studied at a station at 34 m depth in Ancón Bay (Peru) before and during two El Niño (EN) events. Of these events, 1982-83 is considered the strongest, and 1991–93 one of the most prolonged in the 20th century. On the oceanographic scale, EN 1982–83 ranges as "very strong", whereas EN 1991–93 ranges as "moderate".
The thermal anomalies at the station during EN 1982–83 (+ 7.8 °C) were almost twice those of EN 1991–93 (+ 4.1 °C). However, the community changes were not in all cases proportional to the extent of warming. Species numbers increased in a similar way (up to 24 species from near zero in each of the two events), but maximum faunal density was five times higher, and mean biomass was twice as high in 1982–83 compared with the event a decade later. Species diversity was slightly higher during EN 1982–83, whereas successional and trophic changes occurred on a broader scale during EN 1991–93. On the whole, the impact of the long-lasting event on the small soft-bottom macrofauna was not much weaker than that of the exceptionally strong event.
The authors discuss the mechanisms which may be responsible for the differences and similarities encountered in the benthic community dynamics during these two events. Both in the unusually strong and the unusually long EN, the community revealed a pattern of early biological response several months ahead of the onset of local warming which marks the official begin of EN. The question is addressed to what extent the increase of certain parameters in the benthic community could be used for predictive purposes.  相似文献   

Geophysiology and Parahistology of the Interactions of Organisms with the Environment*     

Wolfgang E. Krumbein 《Marine Ecology》1996,17(1-3):1-21

Abstract. Ecology and Global Ecology (GE) are terms by which the relations between the organism (or living matter as a whole) and the environment (or Earth as a whole) have been treated for almost a century. Geophysiology and Parahistology (PH) are terms slowly replacing older scientific thoughts jointly with an increasing number of modifications and alterations of the Darwinian Evolution (DE) concept. Somehow Geophysiology and Parahistology seem to describe evolution in a non-Darwinian domain. According to V.I. Vernadsky (1929,1930,1988) - the great Russian naturalist and biogeochemist - the biogeochemical processes on Earth are controlled by the force of living matter rather than by species associations developing in and with individual ecosystems as expressed by darwinian evolutionary terms. He also claimed that Goethe was incorrectly regarded as a predecessor of DE by some authors (including Darwin) and that “Natur” (nature) and “Lebendige Natur” (the totality of creatures) are two very different things for Goethe. Detailed analyses of microbial mat systems in the German Wadden Sea and in artificial hypersaline WInogradsky columns have shown that the totality of creatures and matter around them i.e., the “lebendige Natur”sensu Goethe or “living matter”sensu Vernadsky of such environments control to a considerable extent the structure, stability. and (geo-)morphology of sediments and thereby the geological structure of the living Earth. These structures do not follow the rules of sedimentation formulated by the laws of Stokes They represent growth structures (Aufwuchs), whose physics and dynamics are controlled by complex fractal systems. The factors controlling the ultimate shape and stabilisation potential of the eventually resulting rocks and fossils are comparable to tissue development in macroorganisms. Also, certain microbial associations in the sub-recent and in the fossil record may be compared to metazoan tissues. Chemical gradients in the sedimentary column, regulated by the interplay of living matter and sluggish (slow-reactive to non-reactive) compounds, combine to create a pattern of porosity and structure of the resulting deposits that clearly indicates microbial influences and especially those of extracellular polymeric substances on the morphology and texture. The combined effects of microbiota or living matter on the sedimentary record are described as parahistology of sediments in analogy of the histology of tissue on a geological scale. This conceptual living tissue made up of microbially generated rocks and ore deposits cycled through metabolic processes and forced into tissue-like structures by microbial biofilms and mats may extend down to the upper mantle of Earth and far up into the stratosphere when Earth is regarded as a living entity over geological periods. We may have to conceive Earth as a living specimen, which is breathing at a frequency of thousands of years instead of the normal physiological breathing rate of man or an insect. Macroorganisms in all terrestrial systems represent the transport and logistic media, which, however, utterly depend on myriads of intra-, inter-, and extracellular microbial symbiotic partners.  相似文献   

渤海小型底栖生物的丰度和生物量   总被引：9，自引：1，他引：9  

慕芳红  张志南  郭玉清 《中国海洋大学学报(自然科学版)》2001,31(6):897-905

该文是渤海 1997年 6月、1998年 9月和 1999年 4月 3个航次小型底栖生物调查结果。结果表明 ,3个航次小型底栖生物的平均丰度分别为 :(2 30 0± 12 0 6 ) ind/ (10 cm2 )、(86 9± 5 10 ) ind/(10 cm2 )和 (6 32± 4 0 0 ) ind/ (10 cm2 )。平均生物量分别为 :(15 2 1± 6 34) μg(dwt) / (10 cm2 )、(72 5±35 4 )μg (dwt) / (10 cm2 )和 (5 17± 393)μg (dwt) / (10 cm2 )。共鉴定出 14个小型底栖生物类群 ,其中自由生活海洋线虫丰度占绝对优势 ,桡足类丰度居第 2位 ,这两个类群总和占小型底栖生物总丰度的 94 .8%～ 97.5 %。在生物量中所占比例列前 4位的类群依次为线虫、多毛类、桡足类、双壳类 ,加起来超过小型底栖生物总生物量的 80 %。小型底栖生物的 74 %分布于 2 cm以浅表层中。小型底栖生物的丰度和生物量在渤海海峡和渤海中东部较高 ,与环境因子的相关分析表明小型底栖生物的丰度与水深呈极显著的正相关 ,与沉积物的中值粒径呈显著的负相关  相似文献   

渤海底栖桡足类群落结构的研究   总被引：7，自引：0，他引：7  

慕芳红  张志南  郭玉清 《海洋学报》2001,23(6):120-127

渤海1998年9月航次的调查结果.小型底栖生物总平均丰度为(8688±5097)个/m2,底栖桡足类居第2位,平均丰度为(663±569)个/m2,占总数量的76%.根据77种底栖桡足类丰度所做的聚类和标序分析将渤海20个站位划分为4个组合.根据11种环境因子数据所做的聚类和主成分分析将研究海域划分为两个生境、4个亚区.对研究海域进行的分区与自然分区是基本一致的.支配研究海域底栖桡足类群落结构的主要环境因子是水深和沉积物粒度.  相似文献   

Sedimentary facies and paleoenvironmental interpretation of a Holocene marsh in the Gironde Estuary in France     

WANG Jianhu  MASSE Laurent  TASTET Jean-Pierre 《海洋学报(英文版)》2006,25(6):52-62

1Introduction Since the last glacial maximum, the Holocenehas been marked by a rapid rise in sea level. After6 000 a BP, the present-day level was reached andthe rate of sea-level rise (SLR) decreased rapidly(Morzadec -Kerfourn, 1974; Kidson, 1986 ).These…  相似文献   

Pore-water distribution and quantification of diffusive benthic fluxes of nutrients in the Huanghai and East China Seas sediments     

NI Jianyu  LIU Xiaoy  CHEN Qijiang  LIN Yian 《海洋学报(英文版)》2006,25(1):90-99

1 Indroduction The coastal zone and continental shelf area is an important region in the global biogeochemical cycle of nutrients in the ocean. This portion of the global ocean interacts closely with the continents, atmosphere and the open ocean in a comp…  相似文献   

Diet of albacore Thunnus alalunga from the waters of Mauritius (western Indian Ocean) inferred from stomach contents and fatty acid analysis     

Z Dhurmeea  H Pethybridge  EV Romanov  C Appadoo  N Bodin 《African Journal of Marine Science》2020,42(2):131-140

The diet of albacore Thunnus alalunga from their spawning ground in the waters of Mauritius was investigated. The stomach contents of 249 albacore individuals, caught by industrial longliners and artisanal fishers, was analysed, and the dominant prey taxa were selected for lipid and fatty acid (FA) analysis. The FA profiles of prey were compared with those of liver tissue of spawning-capable and post-spawning female albacore, using multivariate analysis. Whereas stomach content analysis identified cephalopods and crustaceans as the dominant prey items in number, FA-profile analysis identified crustaceans and fishes as the most-frequently consumed prey of post-spawning female albacore. In contrast, the FA profiles of spawning-capable albacore and those of prey showed very low similarity. Analysis of the prey suggests that although cephalopods, crustaceans and fishes could all provide albacore with the required lipids and FAs, cephalopod prey seem to be less desirable owing to their lower energy content (i.e. low in total lipid, triacylglycerol, 16:0, 18:0 and 18:1ω9). Instead, the most beneficial food appeared to be locally available fishes, which are more energy-rich and have a higher docosahexaenoic acid/ eicosapentaenoic acid ratio. These results provide new information on the trophic ecology of albacore, promote our understanding of the importance of prey type for successful reproduction of albacore, and highlight the advantages of FA profiling to study diet.  相似文献   

An inexpensive instrument for measuring benthic current velocity and direction at sea     

J. R. Craig  S. J. Kennelly 《Estuarine, Coastal and Shelf Science》1991,32(6)

An instrument which measures the velocity and direction of benthic water currents at depths of up to 80 m is described. Characteristics of this meter include: (i) readings are not affected by water flow during sinking or retrieval; (ii) it is portable; (iii) it operates unattended; (iv) it is inexpensive; and (v) it requires only simple maintenance. A timing circuit which operates two time periods in succession is used to activate and de-activate a revolution counter and a fluidfilled compass which are mounted on a special frame and vane system. In the field, the instrument accurately measured average current velocities of up to 6 m s⁻¹. Data are presented which illustrate the usefulness of this instrument in describing the velocity and direction of benthic currents along the east coast of Australia and demonstrate a positive correlation between benthic current velocity and catch rates of the commercially-exploited spanner crab Ranina ranina.  相似文献   

Benthic Standing Stock and Metabolic Activity in the Bathyal Red Sea from 17°N to 27°N     

Olaf  Pfannkuche 《Marine Ecology》1993,14(1):67-79

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Food and feeding ecology of juvenile albacore, Thunnus alalunga, off the Bay of Biscay: a case study     

Pusineri  C.; Vasseur  Y.; Hassani  S.; Meynier  L.; Spitz  J.; Ridoux  V. 《ICES Journal of Marine Science》2005,62(1):116-122

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