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长江口及邻近海域冬夏季浮游植物营养限制及其比较 总被引：3，自引：1，他引：3
2001年7月27日至8月11日,2002年1月8~19日在长江口及邻近海域进行了浮游植物限制因子测定的现场培养实验.结果显示:在近长江口透明度低于1 m的海域,冬季和夏季浮游植物的生长均受到光的限制.调查海域范围内夏季高浮游植物生物量海区主要集中在舟山渔场和长江口以北两个区域,盐度范围在28~31.冬季高浮游植物量海区向东南方向移动.夏季浮游植物的生长按照受限情况划分为4个区域:Ⅰ.近河口光限制区;Ⅱ.磷潜在的限制区;Ⅲ.氮、磷潜在限制过渡区;Ⅳ.氮潜在限制区.冬季划分为3个区域:Ⅰ.近河口浮游植物光限制区;Ⅱ.磷潜在限制区;Ⅲ.非营养潜在限制区. 相似文献
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长江口区浮游值物营养限制因子的研究I.秋季的营养限制情况 总被引：23，自引：4，他引：19
１９９８年１１月在长江口及周转海域进行了一个航次的环境调查,并在室内以中肋骨条藻为实验藻种,应用营养加富生物测定法对本海域浮游值物的营养需求状况进行了研究,结果表明,可大致根据离河口的这将此海域分为３个部分;近河口光限制区、过渡带光和磷酸盐限制区、远河口氮盐限制区,Ｐ与Ｎ分别为潜在营养限制因子的界线大致沿盐度为３１的等盐线。并指出,以深解无机氮磷化的判断标准,在悬浮浓度较高的区域会高估磷的限制作用 相似文献
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灌河口北部海域氮磷营养盐分布及富营养化评价 总被引：2，自引：0，他引：2
于2012年5月至2013年2月期间在灌河口北部海域取样,分析讨论了灌河口北部海域营养盐含量的时空变化及其影响因素、海域的富营养化水平和营养级类型。结果表明,整个调查期间,无机磷的含量相对较低,高N/P值显示磷可能成为该研究海域浮游植物生长的限制因子。调查海域近岸及附近海域营养指数E值大于1,处于富营养状态。营养级评价结果显示海域四个季节大多数站位处于磷中等限制潜在性富营养状态。无机氮含量较高,灌河口附近海域普遍超过第四类海水水质标准,其中夏秋季高于春冬季,是由于夏秋季陆源输送增大所致。 相似文献
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台湾海峡浮游植物生长的营养盐限制研究 总被引：2，自引：0，他引：2
2004年7～8月,2005年7月及2006年8月分别在台湾海峡南部海区5个测站进行了浮游植物生长的营养盐限制船基培养实验.结果表明,在调查期间,夏季台湾海峡南部海区浮游植物营养盐的限制状态存在一定的时空差异,氮是浮游植物生长的主要限制因子,并与上升流的存在与否无关;磷的弱限制偶尔会发生,这与涌升水的N/P比值有关.而硅只有在近岸上升流区形成高氮和磷的补充情况下偶尔才会产生微弱限制.在陆架外缘区,浮游植物限制状态较稳定,表现为受N的限制为主导的N、P的共同限制,P限制相对较弱. 相似文献
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文章利用2018年9—11月厦门岛西北海域的现场调查资料，在对海域水质污染状况和富营养化水平进行评价的基础上，分析并讨论浮游植物生物量粒级结构及其环境影响因素。研究结果表明:同安湾在11月处于富营养水平，属于中度或严重污染海域；九龙江口和西海域在9-11月均处于磷中等限制潜在性富营养或磷限制潜在性富营养水平，属于严重污染海域。同安湾和西海域浮游植物分粒级的生物量占比与九龙江口存在明显差异，前者由大到小依次为微型、小型、微微型，后者由大到小依次为小型、微型、微微型。小型浮游植物生物量与硝酸盐和亚硝酸盐、溶解无机氮、溶解无机磷以及活性硅酸盐呈显著正相关，与盐度呈显著负相关；微型浮游植物生物量与真光层深度、铵盐和溶解无机磷呈显著正相关；微微型浮游植物生物量与真光层深度、铵盐和溶解无机磷呈显著正相关，与pH值呈显著负相关。影响浮游植物群落粒级结构的最重要的海洋环境因子是盐度、真光层深度和溶解无机磷，尤其是溶解无机磷浓度，其值一旦升高，浮游植物极有可能从磷胁迫状态发展为赤潮。控制排污、实时监控、增强预警能力和改善生态环境是控制和预防营养盐污染以及赤潮暴发的有效手段。 相似文献
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为了探究南海贫营养海区浮游植物的营养盐限制,2014年10月对南海东北部海区进行综合调查,并于陆坡海盆海区设置了不同种类的氮源和同时添加氮磷的实验组进行现场加富培养,观察不同粒径级的叶绿素以及各级主要浮游植物的响应。实验结果显示陆坡海盆海区浮游植物易对同时添加氮磷产生明显响应,浮游植物总叶绿素从0.1 mg/L左右增长到0.6 mg/L以上,且浮游植物加富5 d左右生物量达到最大值。加富营养盐氮磷后微微型(Pico)叶绿素均显著增长,而聚球藻没有出现与Pico级叶绿素同等程度的增长。31、51站各级浮游植物对单一添加氮源后发生一定程度的增长,不同种类的氮源间差异不大。6号站位由于初始浮游植物群落结构及生态环境不同,响应的方式不同于31、51站,磷酸盐对浮游植物生长的促进能力相对更强。另外营养盐添加后,海区浮游植物原有的种群结构发生了改变,尤其是同时添加氮磷组,硅藻成为主要优势种,主要包括绕孢角毛藻Chaetoceros cinctus,小细柱藻Leptocylindrus minimus,中华根管藻Rhizosolenia sinensis等。 相似文献
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利用特征色素研究长江口海域浮游植物对营养盐加富的响应 总被引：3，自引：1，他引：2
于2009年5月和11月,在长江口邻近海域通过现场营养盐加富实验,研究了浮游植物对营养盐添加的响应。应用高效液相色谱技术分析培养样品中的特征色素组成,通过CHEMTAX软件估算了硅藻、甲藻、隐藻、定鞭藻、金藻、绿藻、青绿藻和蓝藻8个浮游植物类群对叶绿素a生物量的贡献(μg/L)。加富实验结果显示:不同海区或同一海区不同季节的浮游植物生长对营养盐响应不尽相同,这与培养实验水样采集时浮游植物所处的N、P限制状态有着密切的关系。营养盐的加富不仅能够促进浮游植物生物量的增加,也可能引起浮游植物的群落结构的变化。不同浮游植物类群对营养盐添加的敏感性不同,培养实验开始后营养盐的输入使得硅藻在竞争中取得了优势,硅藻所占比重明显上升;但随着培养的进行,营养盐逐渐消耗,一些在低营养条件下竞争能力强的浮游植物类群比如甲藻、蓝藻、隐藻等对生物量的贡献逐渐上升;同时,培养海水中初始浮游植物群落组成对营养盐加富后群落结构的变化有着重要的影响。 相似文献
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浮游植物的营养限制研究进展 总被引：17，自引：0，他引：17
近岸海域受人类影响较深 ,随着污染的加剧和富营养化程度的提高 ,浮游植物爆发而形成赤潮的频率和范围都在加大。深入地了解浮游植物与周围环境尤其是营养盐的相互关系 ,对探讨赤潮发生机制 ,促进海域生态环境的改善 ,具有理论上的指导意义。１对营养限制的理解对营养限制概念的定义有如下几种 :最早的是利比希最小因子定律（１８４０年）中指出的 :植物的生长取决于处在最小量状况的必需物质 ,这种物质就是限制因子。谢尔福德耐受性定律１９１１年认为 ,生物对各种环境因子的适应有一个生态学上的最小量和最大量 ,它们之间的幅度称为耐受限… 相似文献
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Introduction The growth of phytoplankton, which is the main primary producer in the ocean, is always limited by some nutrients such as nitrogen and phosphorus. This limitation has spacial variation, and even in the same area, the nitrogen and phosphorus limitation has seasonal alternation [1]. There are many ways to determine the nutrient limitation of phytoplankton growth. Among them, the enrichment bioassay is the closest to the natural condition and is accepted by many scholars [2-7]. In r… 相似文献
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Rita B. Domingues Tânia P. Anselmo Ana B. Barbosa Ulrich Sommer Helena M. Galvão 《Estuarine, Coastal and Shelf Science》2011
Identification of the limiting nutrient(s) is a requirement for the rational management of eutrophication. Here, we present the first experimental analysis of nutrient limitation of phytoplankton growth and its seasonal variation in the Guadiana estuary (SE Portugal-SW Spain). Ten microcosm experiments were performed during 2005 and 2008, using water samples collected in the freshwater tidal zone of the Guadiana estuary. Nitrate, phosphate and silicate were added in a single pulse, alone and in combinations. Experimental treatments were incubated for 4 days under controlled laboratory conditions. Phytoplankton response to nutrient enrichment was evaluated through changes in biomass (Chla), and abundance of specific phytoplankton groups. 相似文献
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Harilaos Loukos Bruce Frost D.E. Harrison James W. Murray 《Deep Sea Research Part II: Topical Studies in Oceanography》1997,44(9-10)
We construct a one-dimensional ecosystem model (nitrate, ammonium, phytoplankton, zooplnakton and detritus) with simple physics and biology in order to focus on the structural relations and intrinsic properties of the food web that characterizes the biological regime in the central equatorial Pacific at 140°W. When possible, data collected during the EgPac and other cruises were used to calibrate model parameters for two simulations that differ in the limiting nutrient, i.e. nitrogen or iron. Both simulations show annual results in good agreement with the data, but phytoplankton biomass and primary production show a more pronounced annual variability when iron is used as the limiting nutrient. This more realistically reproduces the variability of biological production and illustrates the greater coupling between vertical physical processes and biological production when the limiting nutrient is iron rather than nitrogen. The iron simulation also illustrates how iron supply controls primary production variability, how grazingbalances primary production and controls phytoplankton biomass, and how both iron supply and grazingcontrol primary production. These results suggest that it is not possible to capture primary production variability in the central equatorial Pacific with biological models using nitrogen as the limiting nutrient. Other indirect results of this modeling study were: (1) partitioning of export production between dissolved and particulate matter is almost equal, suggesting that the importance of DOC export may have been previously overestimated; (2) lateral export of live biomass has to be taken into account in order to balance the nitrogen budget on the equator at 140°W; and (3) preferential uptake of ammonium (i.e. nitrate uptake inhibition by ammonium) associated with high regeneration of nitrogen (low f ratio as a consequence of the food web structure imposed by iron limitation) largely accounts for the surface build-up of upwelled nitrate. 相似文献
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C.S. Hassler J.R. DjajadikartaM.A. Doblin J.D. EverettP.A. Thompson 《Deep Sea Research Part II: Topical Studies in Oceanography》2011,58(5):664-677
This study focuses on the comparison of oceanic and coastal cold-core eddies with inner-shelf and East Australian Current (EAC) waters at the time of the spring bloom (October 2008). The surface water was biologically characterised by the phytoplankton biomass, composition, photo-physiology, carbon fixation and by nutrient-enrichment experiments. Marked differences in phytoplankton biomass and composition were observed. Contrasted biomarker composition suggests that biomarkers could be used to track water masses in this area. Divinyl chlorophyll a, a biomarker for tropical Prochlorophytes, was found only in the EAC. Zeaxanthin a biomarker for Cyanophytes, was found only within the oceanic eddy and in the EAC, whereas chlorophyll b (Chlorophytes) was only present in the coastal eddy and at the front between the inner-shelf and EAC waters.This study showed that cold-core eddies can affect phytoplankton, biomass, biodiversity and productivity. Inside the oceanic eddy, greater phytoplankton biomass and a more complex phytoplankton community were observed relative to adjacent water masses (including the EAC). In fact, phytoplankton communities inside the oceanic eddy more closely resembled the community observed in the inner-shelf waters. At a light level close to half-saturation, phytoplankton carbon fixation (gC d−1) in the oceanic eddy was 13-times greater than at the frontal zone between the eddy and the EAC and 3-times greater than in the inner-shelf water. Nutrient-enrichment experiments demonstrated that nitrogen was the major macronutrient limiting phytoplankton growth in water masses associated with the oceanic eddy. Although the effective quantum yield values demonstrate healthy phytoplankton communities, the phytoplankton community bloomed and shifted in response to nitrogen enrichments inside the oceanic eddy and in the frontal zone between this eddy and the EAC. An effect of Si enrichment was only observed at the frontal zone between the eddy and the EAC. No response to nutrient enrichment was observed in the inner-shelf water where ambient NOx, Si and PO4 concentrations were up to 14, 4 and 3-times greater than in the EAC and oceanic eddy. Although results from the nutrient-enrichment experiments suggest that nutrients can affect biomass and the composition of the phytoplankton community, the comparison of all sites sampled showed no direct relationship between phytoplankton biomass, nutrients and the depth of the mixed layer. This is probably due to the different timeframe between the rapidly changing physical and chemical oceanography in the separation zone of the EAC. 相似文献
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营养盐限制浮游植物的生长是近年来国际研究的热点。探讨了目前营养盐限制的判断方法，认为仅靠氮和磷比值来得到磷限制或氮限制的结论是不完善的。根据营养盐限制的判断方法和法则，对长江口水域进行综合分析，认为在长江口及其附近海域，磷不是浮游植物生长的限制因子，而且氮、磷的浓度值都高于限制浮游植物生长的阈值，满足浮游植物的生长。通过1985年8月至1986年8月的长江口调查数据分析，发现从长江河口到远海水域的有些断面上，磷酸盐浓度并不一定离岸越远越低，且也没有周期性的季节变化。因此，尚须对河口区磷酸盐来源作进一步研究。 相似文献
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Alessandra Pugnetti Anna Maria Bazzoni Alfred Beran Fabrizio Bernardi Aubry Elisa Camatti Mauro Celussi Joan Coppola Erica Crevatin Paola Del Negro Alessandro Paoli 《Marine Ecology》2008,29(3):367-374
The changes in the plankton biomass structure in relation to nutrient inputs were studied in the Gulf of Venice (Northern Adriatic Sea), an area characterized by a very marked trophic state variability. The investigation was carried out at two stations, in March, May and July 2005 and 2006, considering the whole water column. The size structure (from picoplankton to mesozooplankton) of both autotrophs and heterotrophs was analysed. Signals of diluted waters and nutrient inputs were more marked in 2005 than in 2006. In 2005, the total plankton biomass was almost double (87 ± 37 μg·C·l?1) that in 2006 (44 ± 26 μg·C·l?1). The variations were determined mainly by phytoplankton, with a 70% decrease, and a shift from a community dominated by microphytoplankton (49 ± 12%) in 2005 to one dominated by bacteria (43 ± 11%) in 2006 was observed. The relationship between the heterotrophic (H) and autotrophic (A) biomass indicated a rapid decline of the H/A ratio with increasing phytoplankton biomass. This study, although temporally limited, is consistent with the results reported for other marine environments and it seems to confirm the importance of nutrient inputs in structuring the biomass of plankton community. 相似文献
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2006—2007年夏、冬季浙东海域叶绿素a分布特征及其环境影响因子 总被引：1，自引：0，他引：1
为更清楚了解浙东海域浮游植物的初级生产力情况,于2006年8月(夏季)和2007年1月(冬季)在浙东海域28°00′～30°00′N、122°00′～127°30′E设置了3条调查断面,共布设25个观测站位,现场采用荧光连续法对叶绿素a进行测定,初步研究了该海域叶绿素a的空间分布特征,并探讨了水体温度、营养盐和浊度对叶绿素a分布的影响。结果表明:夏季,叶绿素a分布趋势为近岸(平均质量浓度为2.01μg/L)>外海(平均质量浓度为0.52μg/L),其主要垂直分布类型为递增型、递减型和单峰型;冬季,叶绿素a分布趋势为外海(平均质量浓度为0.50μg/L)>近岸(平均质量浓度为0.33μg/L),主要垂直分布类型为递增型、均匀型、单峰型和双峰型。夏季调查海域浮游植物叶绿素a平均质量浓度为0.93μg/L,明显高于冬季(0.46μg/L)。温度、营养盐和浊度是影响研究区夏、冬季叶绿素a分布的主要环境因子。 相似文献
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调水调沙后黄河口邻近海域浮游植物群落响应特征 总被引：15，自引：2，他引：13
为研究黄河调水调沙对邻近海域浮游植物群落的影响,2013年7月在黄河第16次调水调沙事件后,开展了水文、化学与生物综合调查。研究结果表明,黄河口邻近海域温度、营养盐浓度整体呈现由河口向离岸区域逐渐递减的分布趋势,盐度呈现由河口向离岸区域逐渐递增的分布趋势,显示了黄河水输入的影响程度。叶绿素a与营养盐浓度在空间分布上呈现出较好的对应关系,在黄河口偏渤海湾侧明显高于偏莱州湾侧,且近河口区明显高于离岸区。营养盐结构分析表明,黄河口邻近海域普遍存在磷酸盐(DIP)的绝对和相对限制;但黄河水沙输入在局部站位缓解了硅(DSi)限制。浮游植物群落结构的空间变化显著受到盐度的影响,在受黄河水输入影响显著的C、D、E断面,蓝藻与绿藻的生物量比例明显增高;影响相对较弱的断面则以硅藻、甲藻为主。浮游植物群落结构与环境因子的主成分分析结果表明,DSi、DIP和盐度是影响该海域浮游植物空间变化的关键环境因子。甲藻、蓝藻与绿藻群落受盐度变化的影响程度明显大于硅藻群落;但甲藻群落对营养盐结构的敏感性低于硅藻、蓝藻和绿藻群落。 相似文献
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A nutrient dynamic model coupled with a 3D physical model has been developed to study the annual cycle of phytoplankton production in the Yellow Sea. The biological model involves interactions between inorganic nitrogen (nitrate and ammonium), phosphate and phytoplankton biomass. The model successfully reproduces the main features of phytoplankton-nutrient variation and dynamics of production. 1. The well-mixed coastal water is characterized by high primary production, as well as high new production. 2. In summer, the convergence of tidal front is an important hydrodynamic process, which contributes to high biomass at frontal areas. 3. The evolution of phytoplankton blooms and thermocline in the central region demonstrate that mixing is a dominant factor to the production in the Yellow Sea. In this simulation, nitrate- and ammonium-based productions are estimated regionally and temporally. The northern Yellow Sea is one of the highly ranked regions in the Yellow Sea for the capability of fixing carbon and nitrogen. The annual averaged f-ratio of 0.37 indicates that regenerated production prevails over the Yellow Sea. The result also shows that phosphate is the major nutrient, limiting phytoplankton growth throughout the year and it can be an indicator to predict the bloom magnitude. Finally, the relative roles of external nutrient sources have been evaluated, and benthic fluxes might play a significant role in compensating 54.6% of new nitrogen for new production consumption. 相似文献
20.
Laboratory experiments of bioassay with Pltaeodaetytum tricornutum, Chatoceros didymus, Chaetoreros calcitraus and Heterogtoea sp. sampled from the Changjiang Estuary in spring and summer, 1986, indicated that both N and P limit phytoplankton growth in the medium with N : P ranged between 8-30, and N limits phytoplankton production in the medium with N: P<8, while P is the limitary nutrient in the N : P>30. Generally, N : P in the Changjiang Estuary waters is 2 times higher than Redfield ratio. The bioassay experiments with high N : P water samples collected from Changjiang Estuary show that phytoplankton production is limited by P. Phytopiankton appears to give priority to the uptake of P at all periods of time. And the optimum N:P for phytoplankton growth is determined to be 18. 相似文献