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1.
在实验室条件下,研究铜在海水及以扁藻、轮虫、对虾等生物组成的食物链中的积累与传递规律。结果表明,各种海洋生物都能直接从海水中吸收铜,铜可沿着海水→扁藻→轮虫→仔虾传递。文章还探讨了本食物链各环节积累铜的主要途径以及影响生物个体铜的累积量的诸因素。  相似文献   

2.
对福田国家级红树林自然保护区近岸水域进行水质及生态调查,结果显示,深圳湾潮汐对红树林中微型生物生态及湿地污染状况产生了最为直接的影响;藻类在红树林中具有较好的水质污染指示作用,其生态功能大于纤毛虫、轮虫等微型生态类群;微型生物可通过食物链对污染物起放大和传递作用,传递途径在水体中以藻→纤毛虫为主,底质中以藻→底栖动物幼虫为主。  相似文献   

3.
海水和海洋食物链网传递137Cs、60Co规律的研究   总被引:4,自引:0,他引:4  
本文叙述在人工条件下,利用示踪法和S-8O智能多道分析器与Ge(Li)探头测量放射性,研究137Cs60Co在海水及以扁藻、泥蚶、对虾和罗非鱼等生物组成的食物链网中的传播规律,测定了食物链网各环节对核素的转移率,结果表明放射性核素在海洋食物链中的传递要考虑海水的影响。纯粹的食物传递是微弱的;食物链网中各环节对60Co的传递率比137Cs大;并且探讨了各种生物摄食核素的主要途径。  相似文献   

4.
15N稳定同位素示踪技术在海水养殖研究中的应用   总被引:1,自引:0,他引:1  
利用Na15NO3和15NH4Cl作为示踪物,研究15N在由海水到亚心形扁藻、卤虫、长毛对虾和棱梭等生物组成的食物链中的传递规律.测定了生物体内15N丰度和15N原子百分超,研究了15N在不同生物相中的转移.结果表明,营养物质在食物链中由低营养阶向高营养阶转移时,在15NH4Cl介质中,卤虫→棱梭的转移率比在Na15NO3介质中高,可达3%以上;棱梭体内15N的积累量也比Na15NO3介质中高.  相似文献   

5.
4种海洋绿藻光合放氢特征的研究   总被引:5,自引:0,他引:5  
四爿藻(Tetraselmis sp.)、微绿球藻(Nannochloropsis occulata)、小球藻(Chlorella vulgaris)和扁藻(Ptatymonas subcordiformis)的放氢特点各不相同。在暗厌氧培养阶段,四爿藻和微绿球藻不释放氢气,小球藻和扁藻释放微量的氢气。随后的光照培养阶段中,4种海藻在天然海水中都释放氢气,四爿藻和小球藻在无硫海水中不释放氢气,而微绿球藻在无硫海水中释放的氢气比在天然海水中的少,扁藻在无硫海水中释放的氢气为天然海水中的10倍。在4种藻中。亚心型扁藻的光合放氢能力最高。解偶联剂CCCP(carbonyl cyanide m—chlorophenylhydrazone)对该4种藻的光合放氢的影响各不相同,并初步推测了扁藻光合放氢的速度限制因素。  相似文献   

6.
光合细菌对褶皱臂尾轮虫的饵料价值   总被引:3,自引:0,他引:3  
我们自青岛栈桥浅海海泥中分离到一株光合细菌,经鉴定为球形红假单胞菌(Rhodopseudomonas spheroides)。对其生化特性、生长条件以及做为褶皱臂尾轮虫(Brachionus plicatilis)的饵料价值,进行了研究。结果表明,以球形红假单胞菌的新鲜培养物,混以青岛大扁藻(Platymonas helgolandica var.tsingtaoensis)喂养轮虫,轮虫的增殖率明显高于单独使用光合细菌、扁藻和海洋酵母,也高于光合细菌与海洋酵母的混合。提示在轮虫的生产性培养中,以一定浓度的光合细菌与单胞藻混合投喂轮虫,可能取得较高产量。  相似文献   

7.
为评价秦皇岛褐潮现场海水的毒性,作者利用HPLC技术及CHEMTAX,分析了2013年7月2日采自秦皇岛褐潮高峰期微型及微微型浮游植物的色素组成及群落结构;测定了卤虫(Artemia salina)、轮虫(Brachionus plicatilis)存活率和摄食量。研究表明,褐潮海水微型及微微型浮游植物中,海金藻(Pelagophyceae)占主要优势,其生物量占总生物量的72.6%。褐潮海水抑制卤虫存活,卤虫48 h存活率降至77%;对轮虫24 h存活没有显著效应。此外,褐潮海水抑制卤虫、轮虫的摄食,卤虫、轮虫8 h内摄食量分别由(5.5±0.4)ng/个降至(2.4±0.4)ng/个、由(1.5±0.2)ng/个下降至(0.9±0.1)ng/个。该结果与美国的3株褐潮藻的毒性进行了比较。CCMP 1507对卤虫存活有显著抑制作用,其他两株没有显著效应;3株褐潮藻对轮虫24 h存活都没有显著影响。暴露于3株褐潮藻中,卤虫的摄食量均显著较低;其中CCMP 1507在混合饵料中还抑制卤虫、轮虫对其他藻的摄食。对CCMP 1507各组分分析发现,该藻的毒性主要来源于藻细胞。结合现场试验与室内试验结果分析表明,秦皇岛褐潮对卤虫、轮虫有一定的毒性,其毒性与CCMP 1507的毒性相当。  相似文献   

8.
华北半叶紫菜藻胆体的光谱特性和光能传递的研究   总被引:2,自引:0,他引:2  
红藻的光合器是由叶绿体和藻胆体组成的。藻胆体由多种藻胆蛋白和在结构上起连接作用的无色蛋白或多肽所组成。藻胆体与类囊体片层紧密结合,在单位类囊体的片层上藻胆体的数目因生物种类不同及其所处环境条件的不同而异;一般为400—1200个/μm~(-2)。 藻胆体的功能是捕获光能和将光能传递给类囊体片层上叶绿素a,以进行光合作用。 红藻藻胆体中藻胆蛋白之间光能传递顺序为:R-藻红蛋白→R-藻蓝蛋白→别藻蓝  相似文献   

9.
利用错流超滤技术提取天然胶体,研究了胶体的有机碳浓度、粒径和来源对海水小球藻(Chlorellaspp.)、亚心形扁藻(Platymonassubcordiformis)和球等鞭金藻(Isochrysisgalbana)生长的影响。结果表明,当粒径为10kDa—0.2μm、胶体有机碳浓度为4.8—238.4μmol/L时,胶体使小球藻、扁藻和金藻的生长率分别提高了4.0%—7.0%、19.1%—28.9%和2.9%—8.7%。海水小球藻生长率的相对增长百分数(Y)值与胶体有机碳浓度(CCOC)呈线性正相关;亚心形扁藻和球等鞭金藻的Y与CCOC呈多项式相关;胶体对扁藻生长的刺激作用大于球等鞭金藻和海水小球藻。粒径为10kDa—0.2μm的胶体对3种藻的促进作用大于1—10kDa的胶体。河口、河流和生源胶体使小球藻的生长率提高1.5%—14.1%,不同来源的3种胶体对海水小球藻的促进作用依序是河流胶体>生源胶体>河口胶体。以上结果表明,天然胶体含有微藻生长所必需的营养元素,对微藻的生长有显著的刺激作用。  相似文献   

10.
通过对塔玛亚历山大藻(ATHK和AT-6藻株)、链状亚历山大藻(ACDH藻株)和微小亚历山大藻(AM-1藻株)的PSP毒素含量和组成以及它们分别对轮虫、黑褐新糠虾和鲈鱼存活影响的比较研究发现:塔玛亚历山大藻AT-6藻株不产生麻痹性贝毒毒素PSP,而塔玛亚历山大藻ATHK、链状亚历山大藻ACDH和微小亚历山大藻AM-1均产生PSP毒素,其总含量分别为19.74、5.395、5.57fmol/cell(2.60、0.36、1.61pgSTXeq/cell)。塔玛亚历山大藻AT-6对轮虫、黑褐新糠虾和鲈鱼这三种生物均没有不利影响;对于轮虫,塔玛亚历山大藻ATHK和链状亚历山大藻ACDH的96hLC50分别为:200和1200cells/ml,而微小亚历山大藻AM-1无不利影响;对于糠虾,塔玛亚历山大藻ATHK、链状亚历山大藻ACDH和微小亚历山大藻AM-1的96hLC50分别为7000、11000、16000cells/ml;对于鲈鱼,这三株藻的96hLC50分别为3700、4000、20000cells/ml。四株亚历山大藻对三种生物的毒性大小与其PSP毒素含量和组成无直接的相关关系,其毒性作用可能来自其他未知毒性物质。塔玛亚历山大藻ATHK不同组分分别对三种生物的毒性比较研究表明:藻细胞重悬液和藻液对三种生物的不利影响最为显著,去藻过滤液和细胞碎片对轮虫和鲈鱼没有明显影响,但糠虾的存活率有所下降;细胞内容物对轮虫和糠虾也无影响,但对鲈鱼的存活有一定影响。以上研究表明:不同亚历山大藻的毒性大小存在差别,其对不同生物的危害机制也不相同,除PSP毒素外,亚历山大藻可能还存在其他的毒性物质。  相似文献   

11.
Transfer rule of 137C3 and 60Co in seawater and an arrificial food web which made up of Platy-monas, Arca, tenaeus and Tilapia were studied.The results showed that the transfer of nuclide could be realized in a longer food chain in which seawater contained radioactivity, the transfer along food chain alone was slight, the pathway of nuclide uptaken by organism was mainly from seawater,but the pressnce of the food was helpful to the transfer of the nuclide, the transfer efficiency of 60Co by every member in the marine food chain was greater than that of 137C3.  相似文献   

12.
This study assessed whether trace elements present at Deception Island, an active submarine volcano in the Antarctic Peninsula, show enhanced biological availability to the local marine community. Using a weak acid extraction method to dissolve organic material and leach associated but not constitutive trace elements of sediments, fifteen elements were measured from seafloor sediment, seawater particulates, and tissues of benthic (bivalves, brittlestars, sea urchins) and pelagic (demersal and pelagic fishes, krill) organisms collected in the flooded caldera. The highest element concentrations were associated with seafloor sediment, the lowest with seawater particulates and organism tissues. In the case of Ag and Se, concentrations were highest in organism tissue, indicating contamination through the food chain and biomagnification of those elements. The elements Al, Fe, Mn, Sr, Ti, and to a lesser extent Zn, were the most concentrated of the trace elements for all sample types. This indicates that the whole ecosystem of Deception Island is contaminated with trace elements from local geothermal activity, which is also reflected in the pattern of element contamination in organisms. Accordingly, element concentrations were higher in organisms collected at Deception Island compared to those from the neighboring non-active volcanic King George Island, suggesting that volcanic activity enhances bioavailability of trace elements to marine organisms. Trace element concentrations were highest in digestive tissue of organisms, suggesting that elements at Deception Island are incorporated into the marine food web mainly through a dietary route.  相似文献   

13.
海洋中存在着大量的颗粒,包括大型聚合颗粒(即海雪,粒径>500μm)、小型聚合颗粒(1~500μm)和亚微米颗粒粒径(<1μm)等。颗粒在海水中营造了不同于纯海水的小生境,其中生活着与自然海水中不同的生物。异养细菌、蓝细菌、真核藻类、鞭毛虫、纤毛虫等微食物网生物可以黏附在海洋颗粒上,或生活在颗粒内部,其丰度高于周围水体中的自由生活生物,这可能是由于颗粒提供了更适宜生长的营养环境。本文综述了海洋浮游微食物网生物在海洋颗粒形成和沉降中的作用。微食物网生物在颗粒物的形成过程中起到很重要的作用,它们可以直接促进颗粒形成,也可以彼此结合成颗粒,或微型浮游动物排粪形成颗粒。微食物网生物还可以对颗粒进行转化,影响颗粒的大小、沉降速度、或对颗粒及其黏附生物进行摄食。微食物网生物由于本身较小,沉降较慢,但这些生物和颗粒的结合使得微食物网生物在碳通量中发挥重要的作用。  相似文献   

14.
本文阐述了生物海洋学的内容及其研究状况。根据我国沿海特点,建议我国今后对生物海洋学研究的重点是:1.对不同水域初级生产力的研究。2.对沿海小型底栖生物在海洋生态系统能流和物质循环中的作用研究。3.河口,有代表性海域可溶性有机物(DOM)、颗粒有机物(POM)的来源、数量分布、化学组成,以及在海洋食物链的作用和鱼虾产卵场变动关系的研究。4.沿海养殖环境生原要素循环、环境容量及病害发生的环境研究。5.海洋生物对重要有机污染物和海藻毒素的吸收、富集、代谢、在食物链传递,以及生态影响和生态监测研究。6.沿海植物性碎屑向近海输运,及其在食物链中的作用研究。7.浮游生物的群集、支配群集因素,以及和渔业关系的研究。8.选择代表性海域开展物质通量的研究。  相似文献   

15.
The dissolved organic matter in seawater is grouped into two fractions which are defined as having greatly differing reactivities with respect to both chemical and biological decomposition. One fraction, which constitutes the bulk of the material, is extremely stable and inert and is only slowly degraded by either chemical or biological processes. The other fraction, which is composed of trace organic compounds derived from living organisms, contains components such as free amino acids which are rapidly degraded, probably by marine organisms which use these compounds as a food source. Conclusions about the cycle of organic compounds in seawater based on total organic carbon concentrations could thus be misleading, since pathways involving labile trace organic constituents would be completely obscured. Investigations of the distribution, concentration, and possible diagenetic reactions of specific organic compounds are necessary in order to elucidate the cycle of these compounds in the oceans.  相似文献   

16.
海水利用是解决沿海地区淡水资源短缺的重要途径,但其排放的废水可能对海洋生态环境造成不利影响。文中分析了海水的盐度、温度以及携带的化学物质对海洋生态环境的潜在威胁,结果表明:浓海水、温排水排海可能会破坏排放海域的生态环境,影响海洋生物的繁殖、生长和发育,从而导致生物的种类数量、生物量和分布范围等发生变化,需要引起关注和重视。建议海水利用工程建设合理选址、优化设计,鼓励采用循环经济产业模式,延伸海水利用产业链条,以降低对海洋环境的不利影响;并加强排海废水对海洋生态环境影响的研究和监测工作,为改扩建或新建海水利用工程提供环境影响评价依据。  相似文献   

17.
To study the biological impacts of CO2 ocean sequestration on floating marine organisms, a full Eulerian-Eulerian scheme model has been developed in a large-eddy simulation (LES) version using one-way coupling of the equations of seawater flow to the transport equations of the bio-scalar variables. Special attention was paid to deriving the transport equation, involving non-conservative scalars to describe the degree of injury to floating organisms due to the change in the pH environment resulting from CO2 dissolution. The source terms of the transport equations of bio-scalar variables are based on experimental data on zooplankton activities affected by lower pH seawater, allowing construction of empirical sub-models of three kinds of floating marine organisms: Gaidius variabilis, Paraeuchaeta Birostrata, and Multi-organisms. An example is given to show the applicability of the model to the assessment of the biological impact of CO2 sequestration in the ocean. Given an initial CO2 droplet diameter of 8.0 mm and an injection rate of 1.0 kg/sec, the model simulation predicts that the zooplanktons lose approximately 90% of their activity when the lowest pH inside the plume decreases from 7.57 to 5.61. These injured zooplanktons then recovered gradually to their normal state within two hours due to dilution of the plume. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

18.
The seawater chemistry of potentially toxic metals can affect their availability to marine organisms. Investigation of the relationship between metal chemistry and metal bioavailability has progressed slowly due to difficulties in controlling and measuring metal speciation in uptake media. Recent work with strong metal chelators such as NTA and EDTA has allowed a closer examination of how metal chemistry relates to biological accumulation and toxicity.1–3 However, the presence of a strong chelator at membrane transport sites and the possible alteration of microenvironments by strong chelators could create unnatural uptake behavior. This study presents another method for stabilizing metal chemistry in accumulation experiments. A cation exchange resin was used to study Mn54 accumulation by a small bivalve Donax variabilus. The resin proved an effective method for buffering manganese chemistry in seawater and could provide a useful tool to look for subtle effects present in other metal buffered seawater systems.  相似文献   

19.
海水养殖碳循环的实验研究   总被引:3,自引:1,他引:3  
以浮游生物为主体的受控生态实验表明,溶解无机碳和DOC分别占海水碳贮库的89.75%和10.25%;在有机碳贮库中,浮游生物碳占5.43%,细菌碳占7.39%,表明细菌在海水碳循环中起重要作用,这种作用可从虾池样品分析获进一步证实。在食物链(14)C标记实验中,生物对碳吸收率随饵料密度增加而增加,由于饵料利用率的变化,应注意选择最适的饵料密度。鱼虾混养的~(14)C示踪实验表明:营养元素不断从低营养级向高营养级转移,各种生物样品~(14)C放射性活度平均百分比分别是,扁藻84.63%,卤虫8.99%,长毛对虾0.97%,棱鮻5.42%。  相似文献   

20.
分析了东寨港海水、表层沉积物和生物体中重金属Cu、Zn、Pb、Cd、Hg、类金属As的含量及分布特征,并运用单因子指数法、地积累指数法评价了该调查区重金属污染程度。结果表明:东寨港海水中除Pb的含量符合二类海水标准外,其余含量均符合一类海水标准,且远低于渔业水质标准限值;表层沉积物中典型重金属元素含量都符合海洋沉积物质量一类标准,基本属于无污染区;本区湿地沉积物中的重金属含量比岛内及周边区典型红树林湿地略偏高;红树林及暗滩沉积物中重金属比东寨港水底沉积物重金属含量高,表明河口湾潮滩上的红树林区可能是重金属元素的富集区,东寨港目前可能受到了陆源污染的影响;生物体中重金属含量均符合一类标准,符合无公害水产品的要求。  相似文献   

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