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1.
几种海洋浮游动物染色体初步研究   总被引:2,自引:0,他引:2  
曹文清  林加涵 《台湾海峡》1994,13(3):275-279
采用秋水仙素溶液浸泡,空气干燥,Giemsa染色等方法对火腿许水蚤Schmackeria poplesia,太平洋纺锤水蚤Acaretea pacifica(桡足类),百陶箭虫Sagittabedoti(毛颚类)和厦门隔膜水母Leuckartiara hoepplii(水母类)等海洋游动物染色体的数目和形态作了初步分析。结果表明:火腿许火蚤染色体数目为2n=24,太平洋纺锤水蚤2n=20,百陶箭虫  相似文献   

2.
全球变暖作为一个重要的环境问题,自上世纪80年代初就已引起学者的广泛关注。它不仅对海洋生态环境及生物圈已产生了一定的影响。本文主要从浮游动物角度出发综述了全球变暖对其生理活动、生态分布及生物气候学的影响。运用不同温度条件下浮游动物生理学上的变化来说明全球变暖对浮游动物的生理影响;通过分析浮游动物生物多样性、生物量,丰度和生物地理分布等指标来阐述其对全球变暖的生态响应;通过讨论浮游动物的最高丰度时间和繁殖时间这2个重要物候学指标来说明其对全球变暖的响应。最后,提出了今后的研究方向,即调查更广泛的生物功能群、关注处于热带海洋中的浮游动物以及在浮游动物个体水平上开展研究工作。  相似文献   

3.
国际海洋浮游动物研究进展   总被引:6,自引:1,他引:6  
综述了国际上有关海洋浮游动物种群、群落结构、多样性及浮游动物对全球气候变化响应等方面研究进展。海洋浮游动物种类繁多, 数量丰富, 分布广泛, 是海洋生态系统中最重要的生物类群。在海洋食物网中, 浮游动物通过摄食浮游植物控制初级生产力, 同时, 又被更高营养阶层的动物(鱼、虾、鲸、海鸟等)捕食, 充当次级生产者的角色, 其群落结构、种群动态和物种多样性影响鱼类和其他海洋动物资源量, 浮游动物是海洋食物网中关键环节。海洋生态系统动力学过程的关键环节是浮游生物的生物学和生态学过程, 多项国际研究计划以生物多样性和年际变化趋势为研究重点并联系全球变化及响应, 因此, 浮游动物的研究已成为海洋生态研究的核心内容之一。国际上对浮游动物的研究主要集中在以下6个方向:(1)浮游动物生境、种群的分布和扩散动力学研究;(2)浮游动物的群落结构和多样性;(3)浮游动物的实验生态和现场受控生态研究;(4)浮游动物对全球气候变化的响应;(5)深海、南北极、低氧区等极端生境的浮游动物生态学研究;(6)浮游动物研究新技术和方法。  相似文献   

4.
5.
Marine dynamic disasters,including storm surges,huge waves,and sea ice,are the most harmful natural disasters aff ecting coastal countries in the world.Under the infl uence of global climate change,the mechanisms,frequencies,and damage severity of marine dynamic disasters are exhibiting new characteristics.The enormity,unpredictability,and chain eff ects of these disasters have become increasingly prominent,and the losses endured by coastal countries around the world have been increasing year by year.Therefore,the prediction of,risk assessment for,and emergency response to marine dynamic disasters are important issues for disaster prevention and mitigation worldwide.  相似文献   

6.
1994年,日本Kazusa实验室首先启动了淡水蓝藻Synechocystissp.PCC6803的基因组计划,并于1996年完成基因组测序的工作。Synechocystissp.PCC6803基因组大小为3.57 Mb,共有3 168个基因,是目前研究最多也最为透彻的蓝藻基因组。除此之外,美国能源部下属的联合基因组研究所(JointGe  相似文献   

7.
Eight experimental ecosystem enclosures were employed to test the ecological effects of pollutants on marine zooplankton. The results indicated that in the bags treated with metals and sediments, the low level mixed metals (Cd 1.0 ppb, Cu 3.5 ppb,Pb 0.3 ppb, Zn 3.5 ppb, Hg 0.2ppb) inhibited the development of herbivorous copepods to some extent, in  相似文献   

8.
窦勇  王悠  唐学玺 《海洋科学》2011,35(8):89-94
环境污染导致的臭氧层衰减是当今最引人注目的全球变化现象之一。臭氧层的衰减使得到达地球表面的紫外线,尤其是对生物具有严重损伤作用的紫外线B波段(ultrovioletB,UV.B,280~315nm)的辐射增强,从而对全球产生明显的生态学和生物学效应。研究表明,北海海水表面uv.B辐射率的10%能够穿透到6m深的水层;而...  相似文献   

9.
10.
Measurements of carbon in marine “net zooplankton” were made by use of a Leco 70 Second TC-12 Automatic Carbon Determinator. The instrument employs high-temperature (ca. 1600°C), dry-combustion and thermal-conductivity detection of the purified carbon-dioxide combustion product and oxygen carrier gas mixtures. The methodology developed in this study is convenient and rapid (ca. 70 sec per freeze-dried sample), with a mean error (±2σ/x ·100) of ±4.4% at the 3 mg-C level and ±7.4% at the 10 mg-C level when benzoic acid is used as a standard, and ±9.2% at the 5 mg-C level and ±6.0% at the 10 mg-C level when casein is used as the standard. The technique was applied to the “splash zone” marine copepod Tigriopus californicus to obtain an average value of 38.6% C by weight. Concentrated samples of “net zooplankton” of varying size fractions were collected in the Monterey upwelling region over an eight-month period. Values up to 2000 mg-C/m2 ocean surface (0–200 m) were observed in a seasonal cycle doubly peaked for some size fractions but not for others.  相似文献   

11.
近年来基于图像处理方法的浮游动物分类技术逐渐用于海洋生态系统的研究中,相关检测仪器也从实验室处理向原位现场分析发展,这对检测算法的效率和处理速度提出了更高要求。本文根据海洋浮游动物显微图像的形状特点,提出将模板匹配方法与不变中心矩描述方法相结合,先利用模板匹配限定目标初步范围,再比较不变矩确定最终目标动物,并统计动物数量和尺寸。本文方法不受动物方位旋转和尺寸缩放的影响。实验验证结果表明,该方法与传统识别方法相比简单高效,处理速度快,误差范围小,适用于浮游动物的实时原位观测。  相似文献   

12.
This paper reviews the author's research on metabolic activities of marine zooplankton for which the Okada Prize of the Oceanographical Society of Japan was awarded in 1978. The term metabolic activities used here refers to various physiological rate processes of zooplankton, such as respiration, excretion, feeding and growth.On the basis of experimental data obtained by the author and other workers, it is emphasized that all these rates are power functions of the body weight of zooplankton. In other words, the weight specific rates (rates per unit body weight) increase with a decrease in body weight. The habitat temperature of zooplankton can also affect the level of these rates.The relationship between these rates and body weight established experimentally can be applied to the estimation of the total rates of a zooplankton community in the field, by knowing the size distribution of individual zooplankters. The feasibility of this method was tested with the zooplankton community in the Kuroshio region.Finally, the potential importance of microzooplankton in total zooplankton respiration was suggested, based on respiration rate data recently obtained in the author's laboratory.  相似文献   

13.
甾醇在海洋微藻中的分布研究   总被引:1,自引:0,他引:1  
对29种(株)海洋微藻进行不充气培养,用Bligh-Dyer法提取总脂,皂化后氯仿和正己烷(体积比为1:4)提取甾醇,BSTFA衍生后用岛津QP2010气相色谱-质谱分析仪进行GC/MS分析.从29种海洋微藻中共检测到47种甾类化合物,鉴定出36种甾醇和一种甾酮.其中,4位无甲基Δ5甾醇在所有的微藻中均有分布,一些高等生物中常见的甾醇如胆甾醇、菜子甾醇、菜油甾醇、豆甾醇、谷甾醇和褐藻中常见的岩藻甾醇等,在微藻中均有广泛的分布.相对而言,4位无甲基5位饱和甾(烷)醇、4-甲基甾(烷)醇和双羟基甾醇的分布则相对较少,其中许多甾醇如甲藻甾醇、巴夫甾醇、C27:2(Δ5,22/24Me)和C28:3(Δ5,7,22/24Me)等,只在一种藻或同一纲的微藻中被检测到,可以作为对应微藻或对应纲微藻的特征甾醇.认为海洋微藻甾醇的研究可以为海洋微藻化学分类学及饵料营养学研究提供重要参考依据.  相似文献   

14.
Ecological research has been made for quite a long period in some marine-derived saline lakes in the Vest-fold Hills, Antarctica. The results show distinct succession of zooplankton community in those lakes. The change in community structure of zooplankton is related directly to environmental evolution in nature and the variation of lake conditions, such as physical and chemical factors as well. In the Burton Lake, there is a rather stable annual fluctuation in both temperature and salinity, and the community has probably been in the stage of climax succession. The Fletcher Lake is still undergoing a process by unregular tide flood from nearby bay, so that zooplankton community has been changing due to variance in temperature and salinity.  相似文献   

15.
It is indeed my great honor to receive the Okada Prize (1983) for my studies on the population dynamics and production of inshore marine copepods. This article summarizes the lecture I gave under the above title. It has long been postulated that there is some mechanism whereby a species can repopulate after its disappearance from the plankton, since the appearance of many temperature marine copepods clearly occurs on a seasonal basis. During the last decade, evidence of resting egg production has been found for more than 20 species belonging to Temoridae, Centropagidae, Pontellidae, Acartiidae and Tortanidae. In the Inland Sea of Japan, a summer-fall copepodTortanus forcipatus lays diapause (obligatory resting) eggs in the fall, which overwinter in the sediment on the sea floor until the following summer when water temperature reachesca. 15°C. On the other hand, in Onagawa Bay,Acartia clausi is perennial and produces only subitaneous eggs, many of which, however, sink to the bottom and undergo quiescence (facultative resting eggs) due to adverse environmental conditions (e.g. low temperature, deoxygenation, darkness). There are a large quantity (0.5–2.0×106 eggs m−2) ofA. clausi resting eggs in the sediments of Onagawa Bay, which may play an important role in maintaining a more constant planktonic population. The parameters of population dynamics,i.e. the rates of egg production, recruitment and mortality, have been analyzed forA. clausi in Onagawa Bay, by an integration of field and laboratory studies. Recruitment into the planktonic population older than NIII only accounts for 10–20% of egg production. This apparent loss of eggs, which coincides with the benthic resting phase, may be a characteristic feature of the population dynamics of this species. Stage-specific mortality is generally similar in most of the stages, although CI and CVI suffer more severe mortality, possibly as a result of great morphological change in the former stage and heavy predations in the latter. The seasonal change in daily production byA. clausi has also been investigated, its annual production being 2.45 gC m−2. Daily production and biomass (P:B) ratios increase linearly with temperature. Estimated values of production for other inshore marine copepods are reviewed in relation to P:B ratios and the ratio between secondary and primary production.  相似文献   

16.
海洋生物活性多糖的研究现状与展望   总被引:7,自引:0,他引:7  
海洋生物是天然药物的宝库,多数海洋生物能够产生一些粘性物质或多糖类聚合物。与蛋白质、脂肪、核酸等其它生物大分子相比,糖类具有更强的亲水性。这表明,海洋生物通过合成多糖类物质,以保持体内生命活动所需要的自由水分,来适应海洋这个特殊的环境。同时也启迪人们,海洋生  相似文献   

17.
Microplastics can be ingested by marine organisms and may lead to negative impacts at the base of marine food chains. This study investigated the occurrence and composition of microplastics in the sea-surface water and sought evidence of ingestion by zooplankton. Surface seawater was collected using a stainless-steel bucket and sieved directly through a stainless-steel sieve (250-µm mesh), while a 500-μm mesh net was towed horizontally to collect zooplankton, at 11 georeferenced stations off the Kenyan coast in February 2017, on board the national research vessel RV Mtafiti. Microplastic particles were sorted and characterised using an Optika dissecting microscope. Polymer types were identified using an ALPHA Platinum attenuated total reflection—Fourier-transform infrared (ATR-FTIR) spectrometer. A total of 149 microplastic particles, with an average abundance of 110 particles m–3, were found in the surface seawater. A total of 129 particles were found ingested by zooplankton groups, where Chaetognatha, Copepoda, Amphipoda and fish larvae ingested 0.46, 0.33, 0.22 and 0.16 particles ind.–1, respectively. Filaments dominated both the surface-water microplastics and the ingested microplastics, contributing 76% and 97% to those compositions, respectively. White particles were prevalent in the water (51%), whereas black was the colour found most commonly (42%) across the zooplankton groups. The sizes of particles that were in the water were in the range of 0.25–2.4 mm, and those ingested ranged between 0.01 and 1.6 mm. Polypropylene was predominant in the surface water, whereas low-density polyethylene was the most-ingested polymer type. The results provide the first documented evidence of the occurrence, composition and ingestion of microplastics by zooplankton in Kenya's marine environment, indicating that microplastics have the potential to enter pelagic food webs and cause pollution in the study area.  相似文献   

18.
1Introduction The marine environment contains a complex va-riety of plants, animals and microorganisms. Owingto their unique adaptations to the habitat, these liv-ing creatures elaborate a wide diversity of naturalproducts with specific bioactivities, whi…  相似文献   

19.
This study describes changes in abundance of hyperbenthic zooplankton (including meroplankton) and benthic colonists at the seasonally hypoxic seabed of Saanich Inlet, British Columbia, Canada. We used the Victoria Experimental Network Under the Sea (VENUS) cabled observatory to measure water properties and to sample hyperbenthos with a sediment trap at 97 m from September 2008 to September 2009. Some faunal groups exhibited seasonal reproduction, and abundance peaked during their reproductive periods. These included larvae of the barnacle Balanus crenatus, and the crabs Petrolisthes eriomerus, Oregonia gracilis, and Lophopanopeus bellus bellus. Other groups were most abundant in spring and summer when food and oxygen levels were highest and temperature was lowest. These included cumaceans, the siphonophore Diphyes sp., the bryozoan Triticella pedicellata, and tintinnids. We also collected benthic colonists, predominantly bryozoans and polychaetes, on colonization plates deployed in spring/summer 2008, fall 2008/winter 2009, and spring/summer 2009. The total abundance of colonists and of bryozoans did not vary seasonally or with substrate complexity, whereas polychaetes were more numerous in spring/summer deployments and on a highly complex substrate. Taxon richness of colonists was higher in spring/summer 2008 than in fall 2008/winter 2009, whereas an anoxic episode in spring/summer 2009 reduced richness to similar values with that of fall 2008/winter 2009 levels. Substrate complexity had no effect on richness. Juvenile squat lobsters, digitally imaged in fall 2008/winter 2009, were most numerous when oxygen levels were lowest and potentially excluding larger predators. Our study illustrates how season, food availability, temperature, and oxygen can interact to shape community structure in a seasonally hypoxic habitat.  相似文献   

20.
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