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1.
胶州湾浮游植物粒级结构及其时空变化 总被引：1，自引：0，他引：1
基于2003—2010年间对胶州湾分粒级叶绿素a浓度的连续观测,系统研究了胶州湾浮游植物粒级结构的季节变化、年际变化及长期变化特征。结果表明,胶州湾表层浮游植物粒级组成以小型和微型浮游植物为主,其浓度由东北部和北部向湾中间及湾外逐渐递减。不同区域分粒级叶绿素a浓度的季节与年际变化规律相似。小型和微型浮游植物表现出明显的双峰型季节变化,小型浮游植物的高峰值通常出现在冬季,而微型浮游植物则出现在夏季。长期变化结果表明,冬季小型浮游植物所占比例自90年代起表现为增加的趋势,而夏季的变化规律与冬季相反,自1998年开始,小型浮游植物所占比例下降,微型浮游植物比例有所上升。春季和秋季小型和微型浮游植物的贡献率没有表现出明显的升高或降低趋势,但微微型浮游植物的贡献率在2000年之后显著低于2000年之前。统计分析结果表明,温度、营养盐浓度与结构是影响胶州湾浮游植物粒级结构变动的重要因素。 相似文献
2.
2017年4月作者对海州湾临洪河口海域16个站位的常规理化因子以及浮游植物粒级结构进行了采样和分析,结果表明:调查海域盐度和温度均值分别为35.2和11.2℃,均由近岸到外海逐渐增大;悬浮物质量浓度在3.4 mg/L～137.6 mg/L变化,均值为22.8 mg/L,由近岸到外海逐渐减少,水体逐渐清澈; pH均值为8.29,近岸低,外海高; DO均值为9.8 mg/L, COD在0.34 mg/L～6.55 mg/L变化,均值为3.42mg/L,DO和COD分布规律不明显;浮游植物粒级组成以微型与小型浮游植物为主,其叶绿素a质量浓度平均值与范围分别为1.48μg/L(0.68μg/L～3.13μg/L)、9.14μg/L(2.69μg/L～25.50μg/L),且呈现自沿岸河口向外海逐渐递减的趋势;而微微型浮游植物叶绿素a质量浓度平均值仅为0.27μg/L,且分布较不规律;小型浮游植物对浮游植物总生物量的贡献率最大,高达83.89%,微型及微微型浮游植物的贡献率分别为13.60%和2.52%;在相关性分析中,各项环境因子对小型浮游植物的分布有较大的影响,其中悬浮物、pH与小型浮游植物叶绿素a浓度表现出显著相关(P0.05),溶解氧、盐度与小型浮游植物叶绿素a质量浓度呈极显著相关(P0.01),微型、微微型浮游植物的分布与各项环境因子的相关性不明显。 相似文献
3.
浮游植物的分粒级研究是监测浮游植物特征的重要工具，对于深入了解浮游植物动态的作用也不容忽视。本文的研究目的在于揭示长江口邻近海域春秋季不同粒级的浮游植物分布动态，分析浮游植物粒级结构与环境因素以及浮游动物群落结构的关系。通过2010年春季和秋季对粒径分级叶绿素a浓度的现场调查研究发现：春季，浮游植物主要以微型浮游植物占优势；秋季，微微型浮游植物和微型浮游植物共同占优势。相关分析结果表明，温度和富营养化状况是影响微型和微微型浮游植物对总叶绿素a贡献的重要因素。浮游动物的摄食压力可能对小型浮游植物对总叶绿素a的贡献起着重要的作用。 相似文献
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对1998年9月和1999年4月在渤海(37°～41°N,117.5°～122.5°E)进行的两次生态系统综合外业调查,对蓬莱、长岛两地进行15个月的连续资料监测,对渤海调查区浮游植物粒级生物量的平面分布、垂直分布、昼夜变化和周年变化特征进行了研究.结果表明,秋季主要以小型浮游植物为主,然后依次为微型和微微型浮游植物;春季主要以微型浮游植物所占比重最高,其次为小型浮游植物,微微型浮游植物占比例最低.1998年秋季对断面1,2浮游植物粒级组分的垂直分布研究表明,在不同海区(调查区西部、南部、渤海中部和渤海海峡)的不同水层,浮游植物粒级生物量的分布有明显差异.潮汐对浮游植物粒级生物量的周日变化影响较大.蓬莱、长岛两地的连续调查资料表明,浮游植物各粒级组分除微微型浮游植物外1a有两个峰.网采浮游植物在4和7月有高峰,4月是主峰;小型网采浮游植物在6和11月有高峰,6月是主峰;微型浮游植物在4和11月有高峰,两峰值接近;微微型浮游植物在9月有高峰.调查区与其他海区浮游植物叶绿素a浓度粒级组分比较,表明小型浮游植物所占比重较大. 相似文献
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春季季风间期巽他陆架和马六甲海峡表层海水浮游植物群落结构研究 总被引：2，自引：1，他引：1
于2013年3-5月通过走航取样分别对巽他陆架和马六甲海峡表层海水浮游植物叶绿素a生物量和群落结构进行了观测和研究。结果表明:巽他陆架生物量较低,叶绿素a浓度平均值为(0.083±0.043)μg/L,爪哇海的SS4站位生物量最低,仅为0.014μg/L,浮游植物粒级组成上主要以Pico-级为优势,占80%以上;马六甲海峡自西北至东南存在明显的盐度梯度,在盐度最低的SM5站,叶绿素a生物量最高,达到1.080μg/L;马六甲海峡站位叶绿素a浓度平均值为(0.433±0.315)μg/L,同时浮游植物群落结构变动较大。在海峡西北的SM1-SM4站与巽他海峡类似,主要以聚球藻为优势类群,Pico-级浮游植物占60%~80%;在生物量最高的SM5站,同样以聚球藻为优势类群,而在海峡东南段的SM6和SM7站,虽然叶绿素a浓度相对于SM5略有降低,但仍明显高于其他马六甲海峡站位和巽他陆架站位,此两个站位硅藻比例明显升高,均可达20%以上。从优势类群生物量与环境因子和营养浓度的相关性可以看出,研究海区叶绿素a生物量与水体盐度呈现显著负相关(p0.050),说明陆源输入对研究海区生物量具有明显的影响。另外,硅藻生物量也与磷酸盐浓度(p0.050)和硅酸盐(p0.010)浓度均呈现显著正相关;聚球藻在浮游植物群落中的优势度会受到陆源营养盐输入的影响而降低,但仍然是整个研究区域最优势的浮游植物类群。 相似文献
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本文讨论了2013年5月南海东沙天然气水合物区浮游植物生物量和生产力粒级结构特征及其环境影响因素。结果表明，研究海域表现出典型的低营养盐、低叶绿素a、低生产力特征，浮游植物叶绿素a和初级生产力具有明显的次表层最大值现象。东沙海域生物量和初级生产力粒级结构差异性显著，从生物量和生产力贡献度来看，表现为微微型浮游植物> 微型浮游植物> 小型浮游植物。生物量的垂直分布结果表明，春季不同粒级类群浮游植物在真光层内的分布存在明显不同，比如小型浮游植物在真光层内分布较均匀；微型浮游植物则主要分布于近表层或真光层中部，而微微型浮游植物则主要分布于真光层中部和底部。微微型浮游植物在纬度较低的热带贫营养海区之所以能够占主导优势，最主要的原因是其极小的细胞体积和较大的表面积使其有利于营养竞争。相关性分析表明，南海东沙浮游植物各粒级生物量与温度、pH显著正相关，与硅酸盐、磷酸盐显著负相关；浮游植物各粒级生产力与温度显著正相关，与盐度、磷酸盐显著负相关。磷酸盐含量是影响东沙海域浮游植物粒级结构差异的重要因素之一，同时，光辐照度和水体的真光层深度对东沙天然气水合物区不同粒径浮游植物的垂直分布起着更为重要的调控作用。 相似文献
7.
2011 年春夏季黄、东海浮游植物粒级结构 总被引：4，自引：3，他引：1
通过2011年4月和8月利用"科学三号"考察船在黄、东海海域开展的春、夏季综合调查,研究了黄、东海浮游植物粒级结构的分布格局及其时空变动规律,探讨重要环境因子的变动对浮游植物粒级结构的影响。结果表明,春季表层水体中小型、微型和微微型粒级叶绿素a浓度的范围分别为0—4.36、0.02—2.27、0—2.66mg/m3,平均叶绿素a的浓度分别为0.56、0.31和0.14mg/m3,对叶绿素a总量的贡献率分别为55.4%、30.8%和13.8%。夏季表层由大至小3个粒级浮游植物叶绿素a浓度范围分别为:0—6.78、0—2.59、0—0.86mg/m3,平均叶绿素a含量依次为0.50、0.24和0.07mg/m3,对叶绿素a总量的贡献率分别为61.8%、30.1%和8.1%。春季小型浮游植物叶绿素a浓度的垂直分布较为均匀,微型和微微型浮游植物浓度随深度增加呈现逐渐下降趋势。夏季叶绿素a浓度出现明显分层现象,10m层以上小型和微型浮游植物浓度较高,10m层之下浓度迅速降低。微微型浮游植物浓度在不同水层都保持较低水平。受黄、东海不同季节水团影响而引起的温、盐以及营养盐分布格局的变化是影响黄、东海浮游植物粒级结构组成的重要因素。 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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根据2006—2007年度4个季节航次的实测资料,分析了黄海冷水团水域浮游植物叶绿素及其粒级结构的时空分布特征及季节变化规律,结果表明,在研究海域30 m以浅叶绿素总量的平均含量从高到低的顺序为:春季的(1.01 mg/m3)、夏季的(0.81 mg/m3)、秋季(0.72 mg/m3)、冬季(0.68 mg/m3);在叶绿素浓度大于1 mg/m3和小于1 mg/m3的区域浮游植物粒级结构差异较大,在整个研究海域,粒径较小的微型和微微型浮游植物对总生物量的贡献始终占主导(65%),粒径较大的小型浮游植物在冬季和春季贡献率相对较高;从季节尺度看,浮游植物的平均粒级指数从大到小的顺序为:春季的(15.47μm),冬季的(11.08μm),秋季的(8.61μm),夏季的(6.52μm);尽管不同季节水文和化学环境差异显著,但是不同粒径浮游植物的贡献率随总生物量的变化表现出一致性的规律。对环境因子与叶绿素分布的相关分析表明,浮游植物的生长在夏季主要受到营养盐来源的限制,冬季主要受到水体混合引起的光照限制,秋季可能受到磷酸盐和水体混合的共同限制。浮游植物粒级结构的分布格局主要是由各组分在不同环境中的资源竞争优势决定的。 相似文献
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在南海北部、大亚湾及珠江口3个不同水体生物-光学数据的基础上, 研究了浮游植物粒径结构的变化特征, 建立了基于浮游植物吸收光谱提取的浮游植物粒径参数(S<f>)的混合光谱模型。南海海区不同的水体环境下浮游植物的粒级结构有着很大的差异: 在河口和沿岸水体小型浮游植物占优势, 在外海水体微微型浮游植物占优势。浮游植物粒径参数随小型浮游植物增多而减少, 随微微型浮游植物增多而增大。叶绿素a浓度从外海到沿岸逐渐增大, 浮游植物粒径参数随叶绿素a浓度的增大而减小, 它们之间呈幂函数关系。结果表明, 利用混合光谱模型得到的浮游植物粒径参数与南海海区不同水体的生物-光学特征(粒级结构Rpico和Rmicro、粒级指数SI、叶绿素a浓度)有一定的相关性。具体的相关性表示为: S<f>与粒级结构(Rpico和Rmicro)存在一定的关系, 与小型浮游植物和微微型浮游植物之间的线性相关系数分别是0.55和0.65; S<f>与浮游植物粒级指数(SI)有较好的线性关系, 相关系数是0.57; S<f>与叶绿素a浓度呈幂函数关系, 相关系数是0.64。这个混合光谱模型为从光学参数反演浮游植物种群的生态学信息提供了有效的手段, 同时又可用于分析浮游植物优势粒径结构对光学特性的影响。 相似文献
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
12.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
13.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
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The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
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Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding. 相似文献
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Rahul Sharma 《Marine Georesources & Geotechnology》2000,18(3):237-250
Observations on seafloor features from subbottom profiling and seabed photography data show that the undisturbed and natural conditions before the benthic disturbance undergo a substantial change after operation of the disturber. The effects can be seen in the form of deep trenches and grooves, formed by the action of the sleds and the pumping of the sediment along its path, as well as sediment piles on either side of the track. Biological traces such as fecal coils, casts, tubes, burrows, and trails get obliterated in the areas of disturbance and resedimentation. The smooth, uniform nature of the seafloor observed in predisturbance phase shows microtopographic changes in and around the disturbed area as a result of sediment excavation and resettlement. Vertical mixing as well as lateral transport of sediment alter the geological, biological, physical, and chemical conditions on the seafloor, which need to be monitored over time to assess the process and the time taken for restoration of environmental conditions. 相似文献
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Vance P. Vicente 《Marine Ecology》1989,10(2):179-191
Abstract. Long-term changes in the distributional patterns of commercial sponges ( Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater ( e. g. , Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles ( e. g. , Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera ( Spongia and Hippospongia ) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned. 相似文献