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1.
于1991年4月-1992年五月,以金藻和扁藻为材料,用室内一次培养法研究三苯基锡(TPTC)和三丁基锡(TBTC)化合物对光合色素含量的影响。结果表明,两种有机锡对两种藻均有影响,在0.2—0.4μg/L的浓度时有轻微毒性;浓度大于0.5μg/L时,能使光合色素明显减少。对于两种藻叶绿素a72hEC50影响结果:TBTC和TPTC对金藻的均为0.59μg/L;对扁藻的,TBTC是0.87μg/L,而TPTC本出现半效应浓度。对于两种藻的类胡萝卜素72hEC50影响结果:金藻,TPTC是0.57μg/L,TBTC是0.49μg/L;扁藻,TBTC是0.89μg/L,TPTC也未出现半效应浓度。认为,两种有机锡对光合色素有明显的破坏作用。  相似文献   

2.
热致死小球藻生物富集Cr3+的研究   总被引:5,自引:0,他引:5       下载免费PDF全文
研究了热致死小球藻对微量Cr^3 的生物吸附富集和机理。结果表明,培养72h左右的热致死小球藻吸附富集Cr^3 的能力最强;当pH为4.5—5.0,藻浓度为1—2g/L时,死体藻对Cr^3 有较好的生物吸附作用;随着Cr^3 浓度增加,单位质量藻的Cr^3 吸附量呈上升趋势,但其Cr^3 吸附率却急剧下降。热致死小球藻对Cr^3 的吸附可以用Freundlich模型描述,拟合方程为:q=5.3369C11/2.6295,R^2=0.9974;在生物吸附的起始阶段,藻体对Cr^3 的吸附较快,40min左右时藻体达到最大吸附量。  相似文献   

3.
在温度为 ( 2 2± 1 )℃ ,盐度为 2 8的条件下 ,用不同浓度的NaHCO3( 0 ,1 0 0 ,2 0 0 ,40 0 ,80 0 ,1 2 0 0和 1 60 0mg/L)对青岛海洋大学微藻种质库保存的塔胞藻 (Pyramidomonassp.)、小球藻 (Chlorellaspp .)和新月菱形藻 (Nitzschiaclosterium )进行培养。实验结果表明 ,NaHCO3浓度对 3种海洋微藻生长的影响差异显著 ,经过 6d的培养 ,塔胞藻和小球藻的细胞浓度都在NaHCO3浓度为 1 2 0 0mg/L时达到最大值 ;新月菱形藻的细胞浓度在NaHCO3浓度为 40 0mg/L时达到最大值。  相似文献   

4.
锶诱导的氧化胁迫对叉鞭金藻(Dicrateria inornata)的影响   总被引:3,自引:2,他引:3  
李梅  徐瑾  刘志礼  徐俊 《海洋与湖沼》2004,35(5):467-472
采用不同浓度的锶胁迫方法研究了叉鞭金藻生长、叶绿素、MDA含量及三种抗氧化酶SOD、CAT、GPX活性的变化。结果表明,在实验设计的各种Sr^2 浓度内叉鞭金藻均能生长,但Sr^2 浓度较高时生长受到不同程度的抑制,细胞数量比对照组分别减少15.9%和51.0%;叉鞭金藻中叶绿素含量随着Sr^2 浓度的升高而降低,呈负相关关系;叉鞭金藻中MDA含量在较低Sr^2 浓度下稍呈下降趋势,但与对照组相比并无显著差异,而在23.04mmol/L Sr^2 浓度时是对照的1.25倍;低Sr^2 浓度时,叉鞭金藻中蛋白质含量没有大的变化,当浓度超过5.76mmol/L时则引起蛋白质含量下降;叉鞭金藻中抗氧化酶SOD在低Sr^2 时分别降低12.5%、7.5%和9.5%,高Sr^2 时显著升高,为对照组的85.7%;CAT、GPX活性在低Sr^2 浓度时差别不大,但当浓度为23.04mmol/L时升高显著,比对照组分别增加了19.8%和74.4%。  相似文献   

5.
利用啤酒废水养殖螺旋藻研究   总被引:5,自引:0,他引:5  
利用啤酒废水养殖极大螺旋藻(Spirulina marima),研究了废水成分、氮源、藻密度和光照等培养条件对藻生长和蛋白质含量的影响。结果表明,曝气处理的啤酒废水养殖的螺旋藻,相对生长率与CFFRI培养基的几乎一致.蛋白质含量第6天最高,为0.2886g/g干质量,小于CFFRI培养基养殖的。实验确定曝气处理废水养藻的最佳条件是用NaOH调废水pH、藻初始密度取53.8mg/L、光照在1000~10000 1x范围,添加尿素或碳酸氢钠或曝气8h/d。经PSB处理的啤酒废水养殖的螺旋藻,蛋白质为0.4825g/g干质量,与CFFRI培养基养殖的相近。用光合细菌(PSB)处理的废水养藻应控制废水pH为7.0且废水与PSB的体积比为3:1。  相似文献   

6.
均匀设计在后棘藻培养基中的应用   总被引:2,自引:0,他引:2       下载免费PDF全文
将均匀设计的方法应用于一种海洋微藻:后棘藻(Ellipsoidion)培养基的优化。设计了硝氮、氨氮、磷酸盐三因素各五个浓度水平的试验,根据均匀设计表设计了10种培养基,检测细胞浓度、脂肪酸含量和产量。结果表明:在硝氮、氨氮浓度均为1.92mmol/L,磷酸盐浓度为0.082mmol/L,细胞浓度达到最大值167.23mg/L。在硝氮浓度为0.84mmol/L,氨氮浓度为3.38mmol/L,磷酸盐浓度为0.07mmol/L时,EPA含量达到最大值7.748%。在硝氮浓度为0.915mmol/L,氨氮浓度为1.92mmol/L,磷酸盐浓度为0.072mmol/L时,EPA产量达到最大值9.999mg/L。  相似文献   

7.
本文以底栖硅藻筒柱藻(Cylindrotheca sp.)为实验材料,研究了一次性培养过程中,不同硅浓度即:0mg/L(Si0)、8.35mg/L(Si1)、33.4mg/L(Si2)、133.6mg/L(Si3)、534.4mg/L(Si4)和1068.8mg/L(Si5)对藻细胞密度、叶绿素荧光参数、叶绿素含量、总脂含量及脂肪酸组成的影响。结果表明:第5~9d,筒柱藻的细胞密度随硅浓度的增加而增加,硅浓度较高的Si3、Si4和Si5处理组的细胞密度显著高于硅浓度较低的Si0、Si1和Si2处理组的细胞密度。第1~9d,Si5处理组的荧光参数F_v/F_m(PSII的最大光能转换效率)和F_v/F_o(PSII的潜在活性)均显著低于其它处理组。第3~6d,Si3处理组的上述荧光参数均显著高于其它处理组。第1~7d,Si4和Si5处理组的荧光参数φPSII(PSII的实际光能转化效率)和rETR(相对电子传递效率)均显著低于其它处理组,其中Si5处理组的上述荧光参数最低,其次是Si4处理组。筒柱藻的叶绿素含量随着硅浓度的增加而增加,到Si3处理组叶绿素含量达最高值,之后叶绿素含量下降,Si3处理组的叶绿素含量最高,Si0处理组的叶绿素含量最低。筒柱藻的总脂含量随硅浓度的增加而降低,Si0处理组的总脂含量最高,Si5处理组的总脂含量最低。筒柱藻的主要脂肪酸是1 4:0(5.1 5~8.7l%)、16:0(22.40~42.27%)、1 6:1n-7(3l.40~33.12%)、16:3n-4(1.89~8.45%)、20:4n-6(5.95~11.39%)和20:5n-3(EPA)(3.47~8.07%)。饱和脂肪酸含量随着硅浓度的增加而降低,多不饱和脂肪酸含量随着硅浓度的增加而增加,硅浓度对单不饱和脂肪酸的影响差异不显著。经济价值较大的20:4n-6和20:5n-3含量均在Si3和Si4处理组达到最高值。  相似文献   

8.
本文研究测定了卤水浓度、营养盐、温度、光照强度、pH等环境因子对盐田藻垫生长的影响。提出了利于藻垫生长的上述环境因子的最适范围及最适点:1.卤水浓度为6—12°Be。2.在无机氮0~8mg/L,无机磷0~0.8mg/L的范围内,藻垫生长随营养盐浓度的增加而增加。3.温度为30℃。4.在自然条件下,光照越强越有利于藻垫生长。5.pH为8.5。  相似文献   

9.
以正十九碳酸(C19:0)为内标,用HCI-CH3OH溶液提酯化雨生红球藻后进行毛细管气相色谱分析。通过正交实验确定抽提和酯化雨生红球藻脂肪酸的最佳酯化酸度、超声破碎时间和水浴时间。该法对雨生红球藻游动细胞脂肪酸含量测定的相对偏差为0.4%~9.5%;对雨生红球藻孢子为3.0%~11.8%。仪器的检测限为0.942μg。结果表明,雨生红球藻绿色游动细胞的饱和脂肪酸组分主要是C16:0,含量为2.22%;不饱和脂肪酸主要有C16:1,C18:2,C18:1和C18:3,含量在0.764%~3.28%。雨生红球藻孢子中的饱和脂肪酸主要有C16:0和C18:0,含量分别为4.34%和0.477%;不饱和脂肪酸主要为C16:1,C18:2,C18:1和C18:3;含量在0.901%~8.20%。  相似文献   

10.
本文研究了0.1~5mg/L的3-吲哚乙酸(IAA)对球等鞭金藻(Isochrysis galbana)和0.1~3mg/L的IAA对棕鞭藻(Ochromonas neopolitana)的叶绿素荧光参数(PSII最大光能转化效率Fv/Fm、相对电子传递速率rETR、光化学淬灭qP)、细胞密度、叶绿素含量、总脂含量及脂肪酸组成的影响。研究表明,球等鞭金藻和棕鞭藻进行光合作用和生长的最适IAA浓度分别为0.1和0.25mg/L。此条件下,2株藻的Fv/Fm、rETR、qP、细胞密度和叶绿素含量均显著高于对照组和其它处理组。其中,球等鞭金藻的细胞密度和叶绿素含量分别比对照组增加了32.6%和37.1%,总脂含量显著高于其它处理组,但与对照组差异不显著(P0.05);棕鞭藻的细胞密度和叶绿素含量在IAA浓度为0.25mg/L时分别比对照组增加了48.7%和34.4%,总脂含量在IAA浓度为0.5mg/L时显著高于对照组和其它处理组,但与0.25mg/L处理组差异不显著(P0.05)。0.1mg/L的IAA浓度对球等鞭金藻DHA(二十二碳六烯酸)的合成有促进作用,但对其它各脂肪酸(14:0、16:0、16:1n-7和18:1n-9)含量均无显著影响;0.25mg/L的IAA浓度促进了棕鞭藻DHA和多不饱和脂肪酸的合成。研究结果表明,球等鞭金藻和棕鞭藻进行生长和油脂积累的最适IAA浓度分别为0.1和0.25mg/L,此结果为2株藻的大规模培养提供了理论依据。  相似文献   

11.
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.
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   

14.
15.
《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   

16.
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   

17.
18.
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   

19.
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   

20.
The behaviour of an axially pre-loaded cylindrical member of an offshore structure, hit by a supply ship, has been investigated. The effects of axial pre-loading on the dynamic properties of members, the extent of damage and propagation of dynamic instability in the tubular members have also been investigated. Numerical models have been validated using available experimental data from the literature although these are mostly static with no pre-loading. Axial pre-loading was found to change the dynamic characteristics of some cylindrical members quite dramatically while it had no significant effect on others. The study examined whether there was any change in the behaviour between local and global modes when the loading was dynamic rather than static. The effect of damping on the dynamic instability of axially pre-loaded tubes under lateral dynamic loads was also studied. It was observed that for some geometries the quasi-static response can be used to define the boundary between bounded and unbounded dynamic responses. The main contribution of this study, compared with previous investigations reported in the literature, is that both pre-loading and dynamic effects have been included.  相似文献   

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