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1.
新型表面活性剂改性粘土去除赤潮藻研究   总被引:11,自引:1,他引:11  
以赤潮异弯藻为主要研究对象,对其在有机高岭土和有机膨润土作用下的去除情况进行了研究。结果表明,以新型阳离子表面活性剂双烷基聚氧乙烯基三季铵盐改性后的粘土用量为0.03g/L时,在24h内对赤潮异弯藻的去除率可以达到100%,而未经改性的同样用量的粘土并没有对赤潮异弯藻表现出去除作用,这表明改性后的粘土对赤潮异弯藻的去除能力得到了显著的提高。同时还对改性粘土去除赤潮异弯藻的絮凝动力学及其对养殖生物日本对虾仔虾的生态毒性情况进行了研究,发现粘土的种类、用量,改性剂的用量及溶液的pH值等因素都能够影响体系的絮凝沉降速率,通过分析各种影响因素发现在粘土体系中引入有机改性剂是提高其除藻能力的主要因素。另外,毒性实验发现所用改性剂对养殖生物的毒性较小,半致死浓度约为61.9mg/L,比传统的季铵盐的毒性降低了50倍左右,是一种较为安全有效的粘土有机改性剂。  相似文献   

2.
采用一次性培养的方法,研究了盐度和光照强度对赤潮异弯藻增长的效应。结果表明:赤潮异弯藻在3种光照和7个盐度梯度下均可生长。盐度对赤潮异弯藻的生长有极显著的影响(P0.01),光照强度对赤潮异弯藻的生长影响亦显著(P0.05),盐度和光照强度的交互作用无显著影响(P0.05)。不论在哪种光照下,低盐度10、15组赤潮异弯藻虽然能生长,但生长速率和最大细胞数量值均较低,随着盐度的提高,藻的生长速率和最大细胞数量值增大,但盐度增至30以后,即30~40试验组的生长速率和最大细胞数量值之间的差异不明显。而不论在哪个盐度条件下,赤潮异弯藻在3种光照强度下,均以6000lx时的藻细胞密度值最高,生长情况最好。  相似文献   

3.
鼠尾藻和小珊瑚藻对赤潮异弯藻克生效应的初步研究   总被引:2,自引:0,他引:2  
通过共培养的方法,比较了鼠尾藻(Surgassum thunbergii)和小珊瑚藻(Corallina pilulifera)新鲜组织、干粉末、水溶性抽提液、培养水的过滤液对赤潮异弯藻(Heterosigam akashiwo)生长的克生效应。结果表明,鼠尾藻和小珊瑚藻的新鲜组织对赤潮异弯藻的生长都具有显著的抑制作用;与鼠尾藻相比,小珊瑚藻的抑制作用更强。2种大型海藻的干粉末在2个高浓度(1.2,2.4 g.L-1)时对赤潮异弯藻的生长都产生了抑制作用,小珊瑚藻的抑制作用更为明显。2种大型海藻高浓度的水溶性抽提液(24 g.L-1)在实验的48 h内使赤潮异弯藻完全致死。在2种大型海藻培养水过滤液对赤潮异弯藻的作用实验中,在一次性添加方式下,小珊瑚藻的培养水过滤液对赤潮异弯藻的生长没有表现出明显的抑制作用,而在半连续添加方式下,却显著抑制了赤潮异弯藻的生长。与小珊瑚藻相比,无论在一次性还是在半连续添加方式下,鼠尾藻的培养水过滤液对赤潮异弯藻的生长都没有显示出显著的抑制作用。  相似文献   

4.
赤潮异弯藻毒性及毒性来源的初步研究   总被引:26,自引:7,他引:26       下载免费PDF全文
以一种标准实验生物卤虫ArtemiasalinaLeach为实验材料 ,初步研究了一种鱼毒性赤潮藻———赤潮异弯藻Heterosigmaakashiwo的毒性及其来源。结果表明 ,赤潮异弯藻能强烈抑制卤虫的运动能力 ,0 .1、1 .5、6和 2 4h时 ,赤潮异弯藻对卤虫运动的半影响浓度分别为 1 .5× 1 0 4 、7.5× 1 0 3、4.5× 1 0 3、3× 1 0 3cells/ml,但在较低浓度 3× 1 0 3cells/ml的赤潮异弯藻中 ,经过48h,卤虫的运动能力能够恢复到正常水平。通过对该藻各组分 :藻液 (algalculture)、藻细胞悬浮液 (re suspendedcells)、去藻过滤液 (cell freemedium)、藻细胞内容物 (cellcontents)和藻细胞碎片 (cellfragments)的毒性比较 ,发现藻液、藻细胞悬浮液和藻细胞碎片对卤虫的活力有显著抑制作用 ,而去藻过滤液及藻细胞内容物无影响 ,结合致毒途径藻细胞结构 ,可以推断毒性物质来源于藻细胞表面。经苯酚硫酸法和紫外可见光范围的吸收扫描 ,结合该藻藻的细胞结构报道结果 ,分离到的毒性组分推断为多糖类物质 ,本实验结果将有助于了解赤潮异弯藻对海洋生物危害的毒性作用机制  相似文献   

5.
为明确海洋甲藻——网状原角藻(Protoceratium reticulatum)对海洋微藻的化感作用,揭示其化感物质作为植物源抑藻剂的开发潜能,本文探讨了网状原角藻藻细胞和无细胞滤液对几种海洋微藻——东海原甲藻(Prorocentrum donghaiense)、拟旋链角毛藻(Chaetoceros pseudocurvisetus)、米氏凯伦藻(Karenia mikimotoi)和赤潮异弯藻(Heterosigma akashiwo)生长的影响,并进一步选取东海原甲藻和赤潮异弯藻作为受体藻种,以塔玛亚历山大藻(Alexandrium tamarense)作为阳性对照,比较了2种甲藻的藻细胞培养液和无细胞滤液对东海原甲藻、赤潮异弯藻生长的影响差异。通过比较发现,网状原角藻的无细胞滤液比塔玛亚历山大藻能更明显的抑制东海原甲藻和赤潮异弯藻的生长,尤其是对东海原甲藻,基本阻断其生长。  相似文献   

6.
在实验室条件下,研究了温度对赤潮异弯藻生长速率、细胞体积和生化组成的影响。结果表明,赤潮异弯藻在10~30℃之间均能正常生长,25℃时生长速率最高,25℃为其最适生长温度;赤潮异弯藻的细胞体积随着温度的升高大致呈逐渐减小的趋势,10℃时细胞体积最大(823.89μm3),25℃时细胞体积最小(387.98μm3)。进一步分析表明,赤潮异弯藻生长速率与细胞体积(对数值)呈显著的负相关关系(P0.05)。在10~25℃之间,赤潮异弯藻单个细胞的碳、氮含量随着温度的升高呈逐渐减少的趋势,其单位体积细胞的碳、氮含量却呈单峰变化(15℃时结果为峰值)现象;叶绿素a含量在单个细胞和单位体积细胞两个层次上随温度的变化趋势一致,即其在整个温度区间内随着温度的升高均呈逐渐增加的趋势。赤潮异弯藻细胞C∶Chl a和N∶Chl a随着温度的升高呈先减小后增加的趋势,均在10℃时最大,在25℃时最小。  相似文献   

7.
在实验室条件下研究了4种赤潮微藻:中肋骨条藻(Skeletonema costatum)、赤潮异弯藻(Heterosigma akashi-wo)、塔玛亚历山大藻(Alexandrium tamarense)和东海原甲藻(Prorocentrum donghaiense)以及赤潮异弯藻不同组分对海洋桡足类指状许水蚤(Schmackeria inopinus)生殖、生长和发育的影响。结果表明:(1)4种赤潮微藻能够显著延迟指状许水蚤的抱卵时间并导致抱卵率的降低(P0.05),塔玛亚历山大藻、东海原甲藻和赤潮异弯藻导致指状许水蚤卵囊发育所需时间和抱卵间隔时间的明显延长(P0.05),与对照组相比差异显著;(2)4种赤潮微藻明显抑制了指状许水蚤的发育过程(P0.05),其中赤潮异弯藻作用最为显著;(3)赤潮异弯藻4种组分:细胞液、细胞破碎液、细胞过滤液和细胞重悬浮液均能够延迟指状许水蚤抱卵时间,降低其抱卵率,同时藻细胞过滤液、藻细胞重悬浮液和藻细胞液显著延长了指状许水蚤卵囊发育时间和抱卵间隔时间(P0.05);4种组分均可对指状许水蚤的发育产生明显影响(P0.05),但只有藻细胞液对其生长影响显著(P0.05)。结果表明,4种赤潮微藻均能对指状许水蚤的生殖、生长和发育过程产生不利影响,进而对其生活史特征和种群数量产生影响。  相似文献   

8.
从福建云霄红树林区分离筛选出一株对赤潮异弯藻(Heterosigma akashiwo)具有较强抑藻作用的细菌,命名为HSY-03。结合16S rDNA序列分析,该菌与芽孢杆菌属(Bacillus sp.)同源性高达99.0%。通过抑藻方式研究发现菌株是通过分泌胞外活性物质抑藻,属于间接杀藻;胞外活性物质为非多糖、非脂肪、非蛋白类化合物,具有较好的光、热和酸碱稳定性;对供试13株赤潮藻未表现出溶藻效果,表明该菌株抑藻具有一定的种属特异性。菌株HSY-03抑藻效果具有浓度效应,初始终浓度高于5.0%抑藻效果较好。不同生长时期菌株HSY-03对赤潮异弯藻均表现出较好的抑藻效果,但菌株处于稳定期和衰亡期时抑藻效果最好。  相似文献   

9.
研究了从浙江海区分离的一株微小卡罗藻(Karlodinium micrum)对鲫鱼动脉血的溶血性,以典型鱼毒性的赤潮异弯藻作为比较,分别就细胞提取液、去藻上清液和细胞悬浮液的溶血性进行了研究。结果发现:同样处理条件下,以1%的Triton X-100作为溶血度100%的指标,微小卡罗藻细胞提取液的溶血度为70%,赤潮异弯藻细胞提取液的溶血度为32%。微小卡罗藻去藻上清液的溶血度为33%,赤潮异弯藻去藻上清液的溶血度大于100%溶血的TritonX-100组。两种藻的细胞悬浮液溶血度接近0。去藻上清液和细胞提取液具有显著浓度相关的溶血特征。在同样藻密度时,去藻上清液的溶血度大于细胞提取液的溶血度。由于微小卡罗藻在形态上容易与无毒的河口裸甲藻(Gyrodinium estuariales)混淆,因此,对于该藻的环境危害应当加以重视。对于微小卡罗藻具有溶血性的报道尚属首次。  相似文献   

10.
采用实验生态学方法,研究了不同起始密度下悬浮清洁疏浚物对中肋骨条藻Skeletonema costatum和赤潮异弯藻Heterosigma akashiwo生长的影响。研究结果表明,在实验室单培养条件下,清洁疏浚物培养液中,起始密度不同,微藻生长状况明显不同。起始密度为0.2×104 cells·mL-1时,进入指数生长期和静止期的时间延长,但生长所达到的最大细胞密度较高;起始密度为0.8×104 cells·mL-1时,进入指数生长期和静止期的时间缩短,但生长所达到的种群最大密度较低。混合培养条件下,清洁疏浚物培养液中,起始密度不同,导致了微藻种间竞争关系的变化,中肋骨条藻与赤潮异弯藻具有明显的种间竞争,赤潮异弯藻是竞争的优胜者,中肋骨条藻受到赤潮异弯藻的抑制,整个实验周期内细胞密度下降都非常明显,细胞密度明显低于单培养时的细胞密度,而赤潮异弯藻细胞密度并没有明显的减少。在3种不同质量浓度组清洁疏浚物培养液中,质量浓度最高的1 000 mg·L-1培养液中藻细胞密度显著低于100 和500 mg·L-1质量浓度组,而100 mg·L-1培养液中藻细胞密度最高,说明清洁疏浚物质量浓度越高,对海洋微藻抑制影响越为明显,质量浓度越低,影响越小。  相似文献   

11.
通过对神狐海域表层5个沉积物样品进行脂肪酸组成及其碳同位素分布特征测试和研究,结果表明总脂肪酸含量分布为5.14~8.99 μg/g,碳数分布范围从C12到C32,类型包括正构饱和脂肪酸、支链脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸和类异戊二烯酸等计48种;样品中饱和的短链脂肪酸主要来自细菌与浮游生物,而长链饱和脂肪酸来自陆源高等植物,其比例表明研究海域中海洋细菌与浮游生物输入量远远大于陆源高等植物的输入。支链脂肪酸10me16:0与单不饱和脂肪酸18:1ω9、16:1ω9主要来自硫酸盐还原菌,而单不饱和脂肪酸16:1ω7很大可能来源于硫氧化菌,比较相对含量得出神狐海域表层沉积物为还原环境。样品中检测出8种类异戊二烯酸,主要是植烷酸和17,21-ββ二升藿烷酸,及少量的姥鲛酸,推测为叶绿素a和细菌微生物的共同贡献。  相似文献   

12.
本文利用采集于我国三大油田的五种原油样品开展了长达210天的溢油风化模拟实验,并依据相对偏差和重复性限数学分析法,进行溢油风化过程分析和诊断比值应用效果评估。研究结果表明:经过210天的风化,溢油鉴定诊断比值发生明显改变;其中来源于萜烷、甾烷和多环芳烃的诊断比值变化率要远低于正构烷烃,可用于中长期风化溢油鉴定。此外,研究发现,在这些有效诊断比值中有4个变化率较小,相对偏差低于5%,保持了较好的稳定性,更适合于重度风化溢油鉴定。  相似文献   

13.
开发绿色环保防污剂是海洋船舶防污涂料研究的重要方向,查明防污活性化合物分子结构中的防污活性基团,是设计开发新型防污剂的关键。本文合成了三种结构相似的苯酰胺类化合物HNOB、DOLPA和DHNOB,通过FTIR,1H NMR,13C NMR测试表征三种化合物的分子结构,利用典型污损生物硅藻和贻贝作为目标生物,测试其对硅藻和贻贝附着的影响,并将分子结构与防污活性进行对比,初步探讨影响防污性能的活性基团。硅藻和贻贝附着实验均表明,HNOB的防污性能较好,半数抑制浓度远低于DOLPA和DHNOB。通过结构对比分析发现,极性和非极性结构的协同作用比单一的极性基团或非极性长碳链基团能更好地赋予苯酰胺类物质良好的防污性能。该研究初步探讨了苯酰胺类化合物的构效关系,有助于新型防污活性化合物的设计开发和结构优化,并对探究该类化合物防除污损生物附着的机理和快速筛选有潜力的防污化合物具有重要意义。  相似文献   

14.
辛一  路延笃  徐健 《海洋科学》2015,39(10):15-20
从微拟球藻高产油藻株IMET1 的cDNA 中, 克隆出一个I 型脂酰辅酶A: 二脂酰甘油酰基转移酶的编码基因NoDGAT1A, 该基因共编码437 个氨基酸, 与拟南芥I 型DGAT 的氨基酸序列相似度为38%, 且含有至少9 段高疏水区。随后, NoDGAT1A被转化入营养缺陷型酿酒酵母三脂酰甘油合成突变株H1246 中进行诱导表达。结果表明, 在外加二十碳五烯酸(EPA)时, 表达NoDGAT1A 的H1246 能够产生三脂酰甘油(TAG), 针对其TAG 的分析表明, 与酵母DGAT 相比, 表达NoDGAT1A 的H1246 产生的TAG 中含有更多的EPA, 说明NoDGAT1A 具有更强的合成含EPA 的TAG 之能力。此外, 16: 0(63.82%)和18: 0(27.98%)是其TAG 中主要的脂肪酸链成分, 说明NoDGAT1A 合成的TAG 侧链仍以长链饱和脂肪酸为主。NoDGAT1A对微拟球藻中TAG 的合成具有重要作用, 也为以微拟球藻为模式的产油微藻TAG 和EPA 代谢网络提供参考。  相似文献   

15.
海洋附着细菌对冠瘤海鞘幼体附着和变态的影响   总被引:7,自引:0,他引:7  
从冠瘤海鞘、皱瘤海鞘及乳突皮海鞘的被囊表面及其附着基和附近的海水中分离到290株细菌,根据其形态和生理生化特征,将其鉴定至弧菌属、肠杆菌属和无色杆菌属等10个属.分析海鞘被囊表面及其附着基和海水中的细菌组成,并从各属中挑出的29株细菌中分离筛选出附着能力较强的9株.将这9株细菌分别制成不同的单种细菌黏膜及9种细菌混合黏膜,检测细菌黏膜对冠瘤海鞘幼体附着和变态的影响.结果表明不同细菌黏膜对冠瘤海鞘幼体的附着和变态起不同的作用.无色杆菌属H-13显著地促进海鞘的附着和变态;弧菌属的H-4对海鞘的附着和变态均起抑制作用;弧菌属H-9明显地促进附着却强烈抑制海鞘幼体变态;其余细菌仅仅对海鞘幼体附着或变态的一个过程起作用或是对两者都没有明显效果.  相似文献   

16.
Constructed wetlands, especially mangroves, have been studied for their usefulness in sewage treatment but the effects of mangrove vegetation and a sewage load on mangrove macrofauna have been given little attention. Ocypodid crabs are important components of mangrove forests and constitute good bioindicators of the functioning of the ecosystem as a whole. In constructed mangrove mesocosms, three vegetation treatments (bare substratum, and Avicennia marina and Rhizophora mucronata seedlings) were subjected to 0, 20, 60 and 100% sewage loads from a nearby hotel. The physiological condition of introduced Uca annulipes and Uca inversa was evaluated in terms of their RNA/DNA ratio after one, five and twelve months, and used as an indicator of ecological function in the system. Crab condition in 0% sewage load was similar to that of wild crabs throughout, suggesting no significant effects of the mesocosms on their RNA/DNA ratio. Overall, both species coped well with the administered sewage loads, suggesting good ecological function in the system. Both species manifested similar patterns in RNA/DNA ratio, being more affected by seasonal fluctuations than by sewage load and vegetation presence and type. Higher RNA/DNA ratios were recorded in the long compared to the short rainy season. Sewage enhanced crab condition in the bare substratum and R. mucronata treatments, especially after one year, probably as a result of enhanced food availability. Uca inversa may be more sensitive to sewage pollution than U. annulipes. In A. marina, no difference in crab condition was observed between sewage loads, and this mangrove yielded the best reduction in sewage impacts. Our results support the usefulness of constructed mangrove areas in sewage treatment, especially if planted with A. marina and inhabited by physiologically healthy ocypodid crabs to enhance the system's performance.  相似文献   

17.
Carbon cycle is connected with the most important environmental issue of Global Change.As one of the major carbon reservoirs, oceans play an important part in the carbon cycle. In recent years, iron seems to give us a good news that oceanic iron fertilization could stimulate biological productivity as CO2 sink of human-produced CO2. Oceanic iron fertilization experiments have verified that adding iron into high nutrient low chlorophyll (HNLC) seawaters can increase phytoplankton production and export organic carbon, and hence increase carbon sink of anthropogenic CO2, to reduce global warming. In sixty days, the export organic carbon could reach 10 000 times for adding iron by model prediction and in situ experiment, i.e. the atmospheric CO2 uptake and inorganic carbon drawdown in upper seawaters also have the same magnitude. Therefore, oceanic iron fertilization is one of the strategies for increasing carbon sink of anthropogenic CO2. The paper is focused on the iron fertilization, especially in situ o  相似文献   

18.
We developed an efficient retrospective optimal interpolation (ROI) algorithm by which we can avoid the overlap of model integration periods, which appears in the procedure of evolving a previous analysis error covariance. If the fixed-lag Kalman smoother (FLKS) is used to determine the analysis state at the beginning of the fixed analysis window as is done for ROI, the FLKS can be considered a suboptimal version of the efficient ROI when the involved model is non-linear and has no errors. We confirm that the efficient ROI analyses are more accurate than the FLKS analyses with the increase of the analysis window size. Nevertheless, the computation costs for implementing efficient ROI are almost the same as those for FLKS. Additionally, the reduced-rank version of the efficient ROI is developed based on the accuracy-saturation property.
From the experiments using Lorenz 3-variable model, it is confirmed that the non-linearity of numerical model, which becomes stronger with the increase of the analysis window size, makes the analysis of efficient ROI more accurate than that of FLKS. Our Lorenz 40-variable experiments show that the average analysis error of the efficient ROI is smaller than that of the FLKS for an analysis window size of up to 4 d. However, the efficient ROI and the FLKS requires almost the same costs for computation. From the results of Lorenz 40-variable model experiments, it is suggested that, by using the reduced-rank formulation of the efficient ROI, we can obtain the suboptimal analysis more cost-effectively rather than FLKS.  相似文献   

19.
Abstract. The patterns and rates of feeding by the copepod Acartia hudsonica and larvae of the polychaete Polydora sp. were investigated during the spring in an estuarine embayment. These dominant macrozooplankters fed upon the natural particulate assemblages (predominantly dino-flagellates) spiked with the toxic dinoflagellate Gonyaulax tamarensis. G. tamarensis was ingested by both zooplankters, as was Heterocapsa triquetra , the most abundant alternative food item. Ingestion rates generally increased as dinoflagellate concentrations increased, resulting in a relatively constant (and low) filtration rate for each grazer. Dinophysis acuminata , another dominant dinoflagellate, was essentially ungrazed. Thus, the zooplankters did not ingest one dinoflagellate and consumed others in proportion to their availability but at low rates. Based on these low rates and the small number of A. hudsonica observed during the spring, we infer minima! grazing impact on a 1980 G. tamarensis bloom. In contrast, the impact of polychaete larvae may have been substantial, since their extreme numerical abundance more than compensated for low filtration rates.
In one instance, the tintinnid Eutintinnus pectinis was accidentally included in a grazing experiment. Our ingestion data demonstrate that A. hudsonica , when presented with a combination of tintinnids and several species of phytoplankton (G. tamarensis and D. acuminata) ingested the tintinnids at high rates, in proportion to their high abundance. Since the nanoflagellate Chroomonas amphioxea was found within the loricae of many of the surviving tintinnids, this also provided a qualitative demonstration of the often-hypothesized nanoplankton to tintinnid to copepod link in a marine food chain.  相似文献   

20.
Based on the approximated theory developed by the authors to describe the interaction of complex solitons that are formed by kinks, i.e., drops of fields of different polarity, the features of the dynamics of intense internal wave solitons are studied in the context of nonintegrable Choi-Camassa equations. These equations describe the evolution of long internal waves with arbitrary amplitudes in a two-layer fluid. Making allowance for the complex character of the limiting amplitude solitons made it possible to study the dynamics of their interaction as longitudinal (not pointlike) formations for the first time. A series of the features of soliton interaction caused by the complexity of their structure is discovered and explained. These include the appearance of solitary waves with opposite polarity in the collision process, anomalously large phase shifts, etc. The existence of these features is verified by numerical experiments in the context of internal wave models permitting the existence of complex solitons.  相似文献   

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