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1.
两种大型海藻粉对重金属离子吸附热力学的研究   总被引:4,自引:0,他引:4  
本文探讨了两种常见大型海藻,即马尾藻(Sargassum fusiforme)和海带(Laminaria japonica)对重金属离子(Cu^2 、Pb^2 、Cd^2 、Ni^2 )的吸附热力学过程.结果表明,这两种海藻粉对重金属离子的吸附曲线基本符合Langmuir吸附模型,其吸附容量受温度的影响,马尾藻和海带粉对Cu^2 的吸附均为吸热过程;25℃和35℃两组实验结果显示,其吸附容量随温度的升高而增加,吸附热分别为59.9、76.8kJ/mol.  相似文献   

2.
采用廉价的多细胞褐藻海黍子对重金属镉离子进行吸附,研究海黍子不同的预处理方法、溶液的pH值、初始Cd^3 浓度、外加盐等因素对Cd^3 的吸附特性的影响。并对吸附机理进行了初步的探讨,发现镉离子与海黍子中的钙离子发生离子交换作用,交换率占总吸附量的38%~50%。适宜的pH范围为3~6,海黍子的最大吸附量高达181mg/g,得出了适宜的吸附等温线方程,并进行了简单的洗脱研究。  相似文献   

3.
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   

4.
海带对重金属的吸附位点研究   总被引:1,自引:0,他引:1  
用甲醇、甲醛处理海带藻粉,对其吸附重金属时羧基和氨基的作用进行研究,经藻粉的红外光谱及吸附实验的分析结果表明;羧基和氨基均参入了吸附过程;化学处理降低了重金属的吸附量。  相似文献   

5.
研究了条纹小环藻(Cyclotella striata)对Cu2+和Zn2+的耐受力、吸附率和吸附量的作用规律.结果表明:Cu2+和Zn2+对条纹小环藻的生长影响显著(p〈0.05),随着Cu2+、Zn2+含量的升高,其对条纹小环藻生长的抑制作用增大;当Cu2+和Zn2+的含量分别高于4.00×10-3、0.01 mg/dm3时,其对条纹小环藻的生长几乎没有影响;Cu2+和Zn2+对条纹小环藻生长的半抑制含量分别为0.26、11.17 mg/dm3.Cu2+含量为1.00 mg/dm3和Zn2+含量为50.00 mg/dm3的组合,对条纹小环藻生长的抑制率达72.28%,Cu2+对条纹小环藻的毒性大于Zn2+.条纹小环藻对Cu2+、Zn2+吸附效果良好,当藻细胞含量为2.45×107cells/dm3时,对Cu2+的吸附率为63.00%;当藻细胞含量为1.75×107cells/dm3时,对Zn2+的吸附率为60.52%;条纹小环藻对Cu2+和Zn2+的吸附量分别为9.26 mg/g(21.30×10-9mg/cell)和20.06 mg/g(46.15×10-9mg/cell)时,Cu2+和Zn2+对条纹小环藻不会产生明显毒性.  相似文献   

6.
极大螺旋藻富积重金属机理的研究   总被引:16,自引:0,他引:16  
于1993年5月由南京大学藻类培养室提供极大螺旋藻藻种,用Zarrouk培养基培养后,用活藻体和甲醛杀死的藻体分别进行吸附实验;过滤出的藻体置于6×10-3g/L左右浓度的Co2+,Ni2+,Cu2+,Zn2+离子混合液中。结果显示,死、活藻体都具有相似的吸附能力,对Co2+,Ni2+,Zn2+的富积大于203倍,对Cu2+的富积大于185倍;用热水提取、DEAE-纤维素D-23柱和SephadexG-200柱纯化后,获得了纯细胞外壁多糖,其分子量为52kD。将该糖溶液盛在透析袋内,并置于4种离子混合液中进行吸附实验,结果显示,核糖对Co2+,Ni2+,Cu2+,Zn2+的富积倍数分别达1744,1644,1340,1750。藻体和多糖对Co2+,Ni2+,Zn2+的吸附都高于对Cu2+的吸附。比较藻体与多糖对4种离子的吸附结果可见,藻体对离子的吸附主要是多糖的作用;多糖的红外光谱显示,金属离子改变OH和CO-NH的吸收峰,表明这两种基团与金属离子发生了络合作用;对Cu2+的络合滴定测定表明,Cu2+与多糖的结合度为0.40。  相似文献   

7.
镉对中华绒螯蟹(Eriocheir sinensis)抗氧化酶活性的影响   总被引:6,自引:0,他引:6  
将中华绒螯蟹(河蟹Eriocheir sinensis)浸泡在2.Omg/L氯化镉(CdCl2)溶液中,分别于第0、6、12、24、48、72、96小时提取河蟹的肝胰腺,测定抗氧化酶:超氧化物歧化酶(Superoxicle dismutase,SOD)、过氧化氢酶(Catalase,CAT)、谷胱甘肽过氧化物酶(Glutathione Peroxiclase.GPx)的活性,探讨了镉(Cd^2 )对河蟹肝胰腺抗氧化酶活性的影响。结果显示,在低浓度Cd^2 环境下,河蟹肝胰腺的抗氧化酶活性随时间发生规律性变化。暴露于Cd^2 后,河蟹肝胰脏SOD活性降低,随时间的延长,在暴露72h后,SOD活性恢复并超过未染毒时22.3%。表明Cd^2 中毒导致细胞内氧自由基大量积累从而诱导酶活性升高;CAT活性先下降后增高,随后减少,最后以低于对照的水平趋于平衡;肝胰腺中GPx酶活性的变化规律与SOD相似,在解除氧自由基毒性方面有一定的协调性。实验表明河蟹抗氧化系统酶对Cd^2 很敏感。而酶活性在短时间内的变化规律可以为镉对河蟹早期的毒性研究提供参考。  相似文献   

8.
研究了不同的培养方式(CdCl2浓度、胁迫时间、接种藻密度等)下钝顶螺旋藻(Spirulina platensis)的去除Cd的能力。结果表明:随着CdCl2浓度的增大,藻体总吸附量呈递增趋势,其中藻体表面吸附量远远大于细胞内含量,占总吸附量的95%以上。培养96h,藻体总吸附量比培养10d小,但单位藻质量去除Cd的能力却高于培养10d的实验组。在其它条件不变的情况下,接种藻密度对藻体去除Cd的能力影响不大。  相似文献   

9.
采用连续培养方法,研究三角褐指藻对汞(HgCl_2)的吸附富集作用。结果表明,藻体对汞有较大的富集能力,加入培养瓶中的汞被藻体富集率在95%以上,富集因子的变化范围在3×10~4—2×10~5之间。三角褐指藻的吸附符合Freundlich吸附公式,其动力学过程是一级反应。并讨论了胶州湾水体中浮游植物与汞含量间的关系。  相似文献   

10.
本文研究了几种金属离子对锯缘青蟹(Scylla serrata)N-乙酰-β-D-氨基葡萄糖苷酶(NAGase)活力的影响.其结果表明:Li^+、Na^+和K^+对酶活力没有明显影响,Mg^2+、Ca^2+和Ba^2+对该酶均有激活作用,激活程度依次为Ca^2+〉Ba^2+〉Mg^2+.Al^3+、Fe^3+、Cd^2+、Pb^2+和Hg^2+对该酶具有一定的抑制作用,2.0μmol/dm^3的Hg^2+可以使酶活力完全丧失.Co^2+对酶的效应是先激活后抑制,Mn^2+对酶仅有轻微的激活作用.Cd^2+和Fe^2+对锯缘青蟹NAGase的抑制作用都呈竞争性-反竞争性混合Ⅱ型效应,Cd^2+的抑制常数Ki和KiS分别为23.9、5.0mmool/dm^3,Fe^3+的抑制常数Ki和KiS分剐为395.5、135.6μmol/dm^3.Ki〉KIS说明酶一底物络合物(ES)与抑制剂的亲和力比游离酶(E)与抑制剂的亲和力大.  相似文献   

11.
云纹石斑鱼淋巴囊肿病病变过程的超微研究   总被引:9,自引:1,他引:9  
于1989—1990年,对海水网箱养殖的云纹石斑鱼自然感染和人工感染的淋巴囊肿病进行电镜观察。观察结果表明,自然感染和人工感染的淋巴囊肿细胞之间并无区别,它们均含有许多包涵体和病毒颗粒;主要描述用患淋巴囊肿病病鱼的皮肤结节匀浆对实验鱼作皮下注射而感染的淋巴囊肿病的超微病理过程,包括病毒颗粒在成纤维细胞胞膜上的附着和成纤维细胞及其内含物的形态变化等过程;此外,病鱼心脏、肝脏、脾脏、肾脏和肠上皮也有不同程度的病理变化。  相似文献   

12.
Heavy Metal Biosorption Sites Studies of Laminaria japonica   总被引:1,自引:0,他引:1  
The role played by the functional groups of Laminaria japonica treated by methanol and formaldehyde in biosorption of the heavy metals was investigated. Infrared spectroscopy analysis and biosorption experiments show that both carboxyl and amino groups join in the sorption; chemical treatment decreased the biosorption efficiency of the heavy metals.  相似文献   

13.
为了研究近岸海带养殖活动对水体光学特性的影响,本文选取山东半岛黑泥湾海域为典型研究区,利用2021年4月和8月在该区的9站同步观测数据,分析其总悬浮颗粒物、藻类颗粒物、非藻类颗粒物以及有色溶解有机物的吸收特性,并计算各组分对总吸收系数的贡献率,同时采用Quasi-analytical algorithm (QAA)算法借助MODIS影像反演了水体总吸收系数,结合实测数据获得了黑泥湾水体吸收特性的季节变化情况。结果表明,有海带养殖季节表层水体藻类颗粒物、非藻类颗粒物、总颗粒物和有色溶解有机物的吸收系数明显大于无海带养殖季节,且春季海带养殖区水体的总吸收系数大于无海带养殖区;海底表层沉积物的再悬浮造成底层吸收系数较大,而在春季成熟期的海带汇聚较大量的有机物质导致中层藻类颗粒物吸收系数相对较高;参考波长向红波移动,QAA_v5算法能够较好地估算该区表层水体吸收系数,且在海带养殖季节水体组分会影响到更长的波段特征。本研究可为深入了解海带养殖对水体各组分浓度和分布、碳循环以及水生生态系统的结构和功能的影响提供参照,并有助于提高近岸水体组分的遥感反演精度。  相似文献   

14.
The Mediterranean mussel Mytilus galloprovincialis is the most significant invasive alien marine species in South Africa and, although not normally found subtidally, has recently been observed colonising heads and stipes of the kelp species Ecklonia maxima in False Bay. We quantified this invasion and explored its ecological implications. Transects laid across kelp beds revealed that 10.34% of kelp individuals surveyed bore canopy mussels, with kelp heads (10.07%) being far more commonly infected than stipes (0.27%). Twenty kelp individuals with infected heads and 20 with infected stipes were separately collected for more-detailed examination. Wet mass of mussels on these kelp heads ranged from 2.5 to 2 462 g (median 86.4 g, interquartile range 14.8–353.8 g) and that of mussels on the stipes from 7.6 to 3 492 g (median 595.5 g, interquartile range 194.0–955.0 g). Mussel clumps consisted mostly of individuals <40 mm in length. Mussel clumps supported a rich biota of 80 invertebrate and 13 algal species. Larger clumps supported more epibiotic species, and those on stipes more species than those of comparable mass on kelp heads. The mussels and their associated epibiotic species negatively affected kelp buoyancy, but rarely enough to overcome natural buoyancy. Some kelp individuals that had been toppled by the weight of mussels and their epibiotic species, however, were encountered in situ. Implications of this invasion include large increases in animal biomass and species richness in the kelp canopy, plus reductions in kelp buoyancy and increased hydrodynamic drag on infected kelps, increasing their probability of being uprooted. Uprooted kelp individuals can raft long distances, potentially transporting both native and alien species to distant sites.  相似文献   

15.
《Coastal Engineering》2001,44(1):37-63
This paper presents a set of results from a laboratory study on water wave propagation above submerged vegetation growing in the surf zone and the effect of submerged vegetation on dune erosion. The study has focused on the kelp Laminaria hyperborea. The reason is that this kelp is commercially harvested along the Norwegian coast and there is a need to obtain better knowledge on the possible consequences of this harvesting. Experiments were run with irregular waves over a sloping bottom, and a kelp field was simulated by 5000 artificial kelp plants in a 1:10 scale. The experiments primarily focused on the effect of kelp upon erosion of a sand dune, wave damping and water velocities. It was found that the water level is a very important factor to the degree of dune erosion, while the kelp has only a minor effect. The kelp does, however, cause significant wave damping and the degree of wave breaking is reduced. It was also found that the kelp modifies the water velocity profile. In a region above the kelp canopy layer, the time-averaged water velocity was shoreward, while the seaward undertow was confined to a region higher up in the water column.  相似文献   

16.
海带苗绿烂病暴发严重威胁海带养殖生产,给海带养殖业造成巨大经济损失.研究发现,海带中的多酚化合物可以抵御海带病害初期病原体侵入.为研究多酚对绿烂海带表面附生菌的抑菌效果,在病烂部位分离出一株细菌,通过16s rRNA基因测序的方法,证实该细菌为小孔芽孢杆菌(Bacillus foraminis).进一步以健康海带为原料...  相似文献   

17.
Sugar kelp (Saccharina latissima) forests have an important ecological function in the coastal zone, as they inhabit a high number and a specific composition of fauna. In 2002, a large-scale disappearance of sugar kelp was observed in Skagerrak and parts of the south-western coast of Norway, and the perennial sugar kelp forests were replaced by opportunistic and ephemeral filamentous algae. For management purposes, including identifying areas for restoration initiatives, maps of where sugar kelp forests are supposed to be found and where and under what conditions they have disappeared are needed. Based on modelled and field-measured geophysical variables and presence/absence/loss data of sugar kelp, we therefore developed spatial predictive probability models (i.e. maps) for sugar kelp potential distribution under natural conditions and areas of kelp loss. The influence of geophysical factors was analysed using generalized additive models (GAMs). Using the Akaike Information Criterion (AIC) for model selection, we found that wave exposure, depth, light exposure and slope best explained the potential distribution of sugar kelp. Areas of sugar kelp disappearance were identified by the combined effect of wave and light exposure. These models were developed into maps presented to the managers.  相似文献   

18.
The most important marine coastal ecosystem in the Chilean coast are kelp forests. This review is based on ecological studies regarding different aspects of subtidal kelp ecosystems along the Chilean coast. It highlights the most interesting findings in (1) biology of subtidal kelp in Chile, with particular reference to (2) habitats formed by kelp, and considered the successful examples and promising results in the (3) kelp as an industrial resource (Biotechnological approach of kelps and aquaculture). The impact caused by (4) El Ni?o-Southern Oscillation is discussed as an important climatic event that could help to forecast the future of the kelp ecosystem. In addition, this literature review outlines the knowledge gaps on subtidal kelp along the Southeast Pacific Coast of Chile, so that research can be strengthened in the future.  相似文献   

19.
Numerous studies suggest that floating macroalgae contribute to population connectivity of the algae themselves as well as of associated organisms. In order to evaluate the importance of floating macroalgae for population connectivity in southern Chile we analysed their spatial and temporal distributions. We estimated the abundance of floating kelp in the Interior Sea of Chiloé and the Los Chonos Archipelago via ship surveys conducted during austral spring (November) and winter (July) of the years 2002–2005. Highest densities of floating kelp (Macrocystis pyrifera and Durvillaea antarctica) were found during spring. Generally, the density of floating kelp was relatively low in areas with high supply of freshwater, and highest abundances were found in large channels opening to the open ocean. We suggest that this pattern is caused by the scarcity of natural kelp beds combined with rapid degradation of floating kelp in the interior fjords and by seaward surface outflow. The maximum densities of floating kelps were found in an area known to be an extensive convergence zone (i.e. estuarine front), which appears to act as a retention zone. In accordance with this distribution pattern, we propose that connectivity between local populations via floating kelp is higher in the outer channels with oceanic influence than in the inner fjords with high freshwater influx.  相似文献   

20.
The partial pressure of CO2 (pCO2) and dissolved inorganic carbon (DIC) were monitored in shallow coastal waters located inside and outside giant kelp beds (Macrocystis pyrifera) located in the Kerguelen Archipelago (Southern Ocean). Photosynthesis and respiration by microplankton and kelp lead to marked pCO2 and DIC diel cycles. Daily variations of pCO2 and DIC are significant in the spring and summer, but absent in the winter, reflecting the seasonal cycle of biological activity in the kelp beds. If the kelp beds seem to favour the onset of phytoplankton blooms, most of the primary production inside the kelp beds is due to the kelp itself. The primary production of Macrocystis kelp beds in the Sub-Antarctic high-nutrient, low-chlorophyll (HNLC) waters off the Kerguelen Archipelago is elevated and closely linked to light availability. This production is significant from October to March and reaches its climax in December at the solar radiation maximum.  相似文献   

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