共查询到20条相似文献，搜索用时 31 毫秒
1.
Lowry's method, adapted to the analysis of small amounts of fresh-water plankton, was selected for the basic evaluation of the published methods of determination of proteins in algae. The protein contents were studied by this method in aqueous, alcohol and sodium hydroxide extract from green algae of the types Ankistrodesmus falcatus, Haematococcus pluvialis, Chlorella vulgaris, Scenedesmus obliquus, Pediastrum boryanum, Chlorococcus spec. and from blue-green algae Microcystis pulverea, M. aeruginosa and Anacystis nidulans. These organisms were cultivated in artificial media under standard conditions and the analysis of proteins was carried out during the growth and stagnation phases. The largest amount of proteins was ascertained in extracts of 2N NaOH, amounting to 7 … 44% according to the dry substance (aqueous extract 1 … 48%, alcohol extract 1 … 23%). As the ageing of the cultures of green algae proceeded, the amount of dry substance increased, but the protein contents decreased. In the samples of blue-green algae there were in all cases the protein contents higher in the stationary phase than in the growth phase. 相似文献
2.
In batch tests with Chlorlla pyrenoidosa, Ankistrodesmus falcatus, Coelastrum cambricum and Scenedesmus obliquus it is demonstrated that hydroxylamine as an extracellular product of metabolism is excreted by these algae into water. The hydroxylamine production is proportional to the number of cells and to the physiological state of the algae. A mixed population of aquatic bacteria does not show any hydroxylamine production, the hydroxylamine concentration in the medium of culture of algae being reduced by their presence. 相似文献
3.
The radium cumulation in Coelastrum cambricum, Scenedesmus obliquus and Microcystis pulverea was studied under conditions of continuous cultivation at constant level of radium in the cultivation medium. The algae were exposed to the concentrations of 30, 300 and 3000 Bq/l 226Ra in the medium for a period of 14 days. It was found that radium started to cumulate immediately after its addition to the culture just as in the stationary type of cultivation, in the continuous cultivation, however, its content decreased with the length of exposure. This is due to the decreasing part of radium adsorbed on the cell surface. While in green algae the portion of radium incorporated into cells increased with the length of exposure, in blue-green algae up to 90% of radium was bound to the surface or gelatinous capsules of the cells through out the experiment. With the three phytoplankton species used, the highest cumulation of radium (nonwashable part) was recorded in Coelastrum cambricum. A dependence of the radium cumulation on its content in the medium was observed in the species Scenedesmus obliquus. 相似文献
4.
Biotransformation of phenyl and methyl mercury chloride was studied in experiments with planktonic algae Chlorella kessleri, Scenedesmus obliquus and blue-green algae Microcystis incerta. To algal cultures cultivated in an inorganic medium the labelled phenyl or methyl mercury hydroxide was added separately in the phase of the logarithmic growth, the resultant concentration being 3.2 × 10?7 M. In intervals of 0, 1, 3, 7, 10 and 14 days samples of the algae and medium were analysed for the total amount of mercury and for the presence of phenyl or methyl mercury. It was found that both methyl and phenyl mercury had accumulated very rapidly in the algae and that up to 70% of 203Hg added was present in the algae during the first 72 hours of the experiment. From the 2nd day onwards, however, methyl and phenyl mercury changed rapidly into inorganic mercury so that by the end of the experiment almost all of the mercury present in algae and the medium was in the form of inorganic mercury. 相似文献
5.
The metabolism of inorganic mercury has been studied in stationary cultures of planktonic algae Chlorella kessleri, Scenedesmus obliquus and Microcystis incerta that were exposed for 14 days to the concentration of 2 × 10?7 M of Hg(II). Individual chemical forms of mercury were determined in algae and in the culture medium at regular intervals. All the studied phytoplankton species started to metabolize mercury immediately after its application, with the exception of the blue-green alga Microcystis incerta. The accumulation of mercury proceeds without interruption till the end of the experiment. After a 14 days cultivation about 60… 80% of added mercury was present in algal cells and the portion of mercury washable from the cell surface did not exceed 2%. It was found that more than 99,5% of mercury in cultivation medium and more than 99,5% of mercury in algae was present in the form of Hg(II). A transformation of inorganic mercury to methyl-, or phenyl-mercury due to the action of algae was not observed. 相似文献
6.
盘星藻在湖泊沉积中的成矿作用 总被引：1，自引：0，他引：1
常被作为淡水湖泊沉积相的指标植物－盘星藻（Ｐｅｄｉａｓｔｒｕｍ ｓｐｐ．）亚化石,在许多国家均有发现,我国新生代油田的芯中亦有较多的盘星藻化石的记载（包括江苏、湖北、河北、西北和东北等地）。本文报告了盘星藻在湖泊中沉积成矿的探索性研究,证明盘星藻等浮游藻类在成矿或成油的过程中有一定的贡献。 相似文献
7.
实时荧光定量PCR方法检测南太湖入湖口产毒微囊藻 总被引：2，自引：0，他引：2
南太湖入湖口产毒微囊藻的丰度对于周边县市取水口的水质安全和太湖水质有着重要影响.以藻毒素合成酶基因mcyE/ndaF为靶基因,建立实时荧光定量PCR检测产毒微囊藻的方法,并对南太湖入湖口7个监测点水样中产毒微囊藻的丰度进行检测,结果表明:该实时荧光定量PCR方法的特异性强及准确性、重复性较好.建立铜绿微囊藻(Microcystis aeruginosa)的标准曲线方程为y=-3.454x+49.88,斜率为-3.454,R~2=0.991,扩增效率E为94.6%,定量检测区间为1.689×10~4~1.689×10~8拷贝数/μl.对南太湖入湖口7个监测点检测表明,夹浦和合溪2个监测点的产毒微囊藻数量最高,预测产毒微囊藻浓度分别为(1.99±0.35)×10~5和(1.47±0.23)×10~5cells/ml.7个监测点的产毒微囊藻的种类较为一致,均为铜绿微囊藻.该方法可以快速准确地检测水体中微囊藻毒素产毒藻种种类和数量,为蓝藻水华监测、预警提供技术依据. 相似文献
8.
O. V. Babanazarova R. Kurmayer S. I. Sidelev E. M. Aleksandrina E. G. Sakharova 《Water Resources》2011,38(2):229-236
The results of observations of some abiotic (water transparency, light intensity, depth, biogenic element concentrations) and algological (chlorophyll concentration, phytoplankton abundance and biomass, the concentration of microcystines—toxins of blue-green algae) characteristics of Lake Nero are given for study periods of 1999–2004 and 2005–2007. Variations of these characteristics in the latter period are shown to be significant. The lake phytoplankton is found to pass in a «catastrophic” manner to monodomination of planktotrichaetic complex of blue-green algae. High-performance liquid chromatography was used for the first time to determine the concentration of microcystines MC-LR and MC-RR in Lake Nero seston. The presence of these types of microcystines in samples was confirmed by mass-spectrometry. A statistically significant correlation was found to exist between the total concentrations of microcystines and the biomass of species of Microcystis genus, suggesting the possible toxicity of representatives of this type of algae in Lake Nero. 相似文献
9.
Laboratory experiments were used to study the sensitivity of both male and female Daphnia magna to a toxic cyanobacterium, Microcystis aeruginosa. Male and female D. magna were fed with M. aeruginosa and a green alga (Scenedesmus obliquus) in different mixtures that included 0%, 25%, 50%, 75% and 100% Microcystis. Growth of both males and females declined with increasing proportion of Microcystis in the diet. Males were slightly less sensitive to Microcystis than females with EC50 for growth inhibition at 72% and 63% Microcystis in the diet, respectively. On monospecific Microcystis diet, mortality rates for males (0.16 d–1) and females (0.17 d–1) were similar. The reproductive rate of females was the most sensitive endpoint with an EC50 of 42% Microcystis in the diet, whereas population growth rates were the least sensitive (EC50 of 74% Microcystis). Microcystis in the diet severely depressed growth and reproduction in Daphnia and poses a severe threat to its survival in which only a switch in reproductive strategy might provide Daphnia a refuge to a Microcystis environment that gradually becomes uninhabitable. 相似文献
10.
David G. Rands Joseph S. Davis Luis R. Arana 《Aquatic Sciences - Research Across Boundaries》1984,46(1):109-116
Analyses of water flowing through coquina showed exclusion of atmospheric CO2 and supersaturation in respect to calcite and hydroxyapatite. Extensive populations growing on the walls and benefiting from
these nutrients included mainly blue-green algae, green algae and diatoms. 相似文献
11.
Summary: An oligotrophic pond and a eutrophic pond of Bhagalpur, India, were studied for phytoplankton distribution and to establish the relationship between this distribution and the physico-chemical properties of the water. Altogether, 114 algal taxa were identified. In Rekabganj pond, diatoms constituted 54.4 % of the algal species followed by green algae (29.4 %), blue greens (11.7 %) and euglenoids (2.9 %). In Ramna pond, blue greens were the most dominant comprising 35.7 % of algal species followed by green algae (32.8 %), diatoms (18.5 %) and euglenoids (8.5 %). The members of Dinophyceae, Chrysophyceae and Xanthophyceae were poorly represented in both the water-bodies. Aphanizomenon flos-aquae, Microcystis aeruginosa, Chlorella vulgaris, Cladophora crispata, Volvox aureus and Euglena spp. were recorded only in Ramna pond, indicating its higher nutrient status. Dinobryon calciformis, many pennate diatoms and desmids, indicators of oligotrophy, were observed in Rekabganj pond only. Measurements of water properties in the two ponds showed that transparency, dissolved oxygen and silicate were higher in Rekabganj pond than in Ramna pond, while total alkalinity, hardness, total dissolved solids, dissolved organic matter, different cations, phosphate, nitrate and chloride were lower in Rekabganj pond than in Ramna pond. 相似文献
12.
Salmo gairdneri, Cyprinus carpio, Poecilia reticulata, Leuciscus idus melanotus, Asellus aquaticus, Ankistrodesmus falcatus and Monoraphidium griffithii were exposed to four growth regulating herbicides, four photosynthesis toxicants, lindane, an anionactive tenside, KCN and Na3[Cu(CN)4] in standardized toxicity tests. The biochemical degradability of the substances was tested with activated sludge. In order to test the possible effects in waters there should be used Salmo for the oligosaprobic zone. Poecilia as well as Ankistrodesmus and Monoraphidium provide reliable estimations for β-mesosaprobic waters. With respect to the longer-term permission of plant protection products, besides Salmo there can be recommended also Leuciscus. 相似文献
13.
云南抚仙湖流域废弃磷矿区水污染现状 总被引：11，自引：5，他引：6
为了探讨不同形态磷酸盐对铜绿微囊藻（Microcystis aeruginosa）和蛋白核小球藻（Chlorella pyrenoidosa）藻细胞生长的影响,采用3种不同形态的磷酸盐：磷酸氢二钾（K2HPO4）,焦磷酸钠（Na4P2O7）和一聚磷酸钠（Na5P3O10）作为BG-11培养基中的添加磷源．从两种藻的生长趋势可以看出,在K2HPO4培养基中小球藻在生长初期生长速度显著高于微囊藻,当小球藻的生长到达静止期时,微囊藻的生长速度便超过了小球藻且其藻密度也高于小球藻;而在焦磷酸钠和二三聚磷酸钠培养基中,小球藻的生长速度要显著高于微囊藻．同时微囊藻和小球藻在K2HPO4培养基中的生长速度则始终高于另两种磷酸盐培养基中的生长速度．藻细胞碱性磷酸酶活性变化曲线也显示,小球藻的磷利用能力要高于微囊藻．由此可见,小球藻对磷的吸收利用能力高于微囊藻,从而表明铜绿微囊藻成为水华优势种并不是取决于其对磷酸盐的吸收利用能力。 相似文献
14.
Bloom‐forming cyanobacteria have been observed in eutrophic waterbodies including drinking water reservoirs all over the world. In this connection investigations about the relevance of intra‐ and extracellular cyanotoxins for drinking water treatment were carried out in laboratory‐ and pilot‐scale experiments. An algae growth phase depended toxin release from cyanobacteria was obtained naturally caused from cultured cyanobacteria (Microcystis aeruginosa) and in a eutrophic reservoir containing Planktothrix rubescens. Results from laboratory‐scale tests using cultivated cyanobacteria and pilot‐scale experiments at a eutrophic reservoir underline the induced toxin release during conventional water treatment. Additional to the known toxin release using pre‐oxidation, it was obtained the first time that the application of flocculation/filtration also effects in toxin release under the conditions investigated, possibly caused by turbulences in pipes and pressure gradients in filters. 相似文献
15.
The cumulation of chromium(III) and (VI) has been studied in batch cultures of planktonic algae Microcystis incerta, Scedenesmus obliquus, Chlorella kessleri and Chlamydomonas geitleri at different chromium and algal cells concentrations. It has been found that chromium(VI) is practically not cumulated in algae, whereas chromium(III) is very rapidly cumulated in all types of algae investigated. The cumulation factor increases with the decrease of the radius of algae cells and it reaches the value of 106 for Microcystis incerta even after a few hours of contact. The kinetics, the cumulation factors and the capacity of algae to cumulate chromium(III) is practically the same for living as well as for dead cells and therefore it can be concluded that the cumulation of chromium(III) is due predominantly to the chemical sorption on the surface of algal cells. 相似文献
16.
太湖蓝藻水华发生风险区划 总被引：1，自引：1，他引：0
湖泊水华是全世界面临的严重生态环境问题之一,对人类和生态系统健康都有重大影响.以太湖为研究区域,基于近年的蓝藻水华及水环境监测数据,结合自组织特征映射神经网络和模糊风险评价方法,对太湖不同监测点蓝藻水华的发生风险进行综合评价,并借助GIS地学统计分析方法对全太湖蓝藻水华发生风险进行区划,绘制太湖蓝藻水华发生风险区划图.结果表明:太湖被分为重度风险区、中度风险区、轻度风险区、微风险区,各风险区基本呈带状分布.从各风险区面积来看,重度风险区、中度风险区、轻度风险区的面积约各占太湖总面积的1/5,而微风险区约占太湖总面积的2/5;从各风险区位置来看,重度风险区主要分布在西北部区域,且从整个湖区来看,蓝藻水华的发生风险等级自西北到东南依次递减.本研究揭示太湖水华灾害风险的空间分布规律,对支撑水环境监测和水华灾害防治方案的制定具有一定的意义. 相似文献
17.
随着全球气候变化和水体富营养化,在过去几十年中蓝藻水华改变了全球的淡水生态系统.蓝藻因独有的藻蓝蛋白而大多呈现蓝绿色,因此其水华也常称为蓝绿藻水华.然而随着蓝藻水华关注度的不断提升,尤其是监测和研究的不断深入,经常在水体中发现蓝藻水华出现黄化的现象.例如,太湖出现的黄色蓝藻水华,冬春季以长孢藻属(Dolichospermum)水华为主,夏秋季以微囊藻属(Microcystis)水华为主.即使外观看起来是蓝绿色的蓝藻水华,但仔细观察形成蓝藻水华的群体颗粒,也有部分呈现黄色,反之亦然.实际上,鉴于色素组成的差异性,也许水体中就没有两个颜色完全一致的蓝藻群体颗粒.目前对于黄色的蓝藻水华及其形成机理,国内外鲜有报道和研究.光照和氮限制被认为是最有可能的原因.在关注蓝藻水华黄化的同时,更应该关注和研究这些颜色变化给蓝藻水华及水环境所带来的风险和挑战,尤其是对水生态管理工作的启发和意义. 相似文献
18.
我国淡水湖库频发水华,不同类群形成的水华特征、危害及其治理方法差异显著,因此,如何区分不同藻种的遥感反射率特征,获取湖泊优势种信息是一个亟待解决的科学问题。研究基于室内藻种培养实验,培养了富营养化湖泊中的典型蓝藻和绿藻藻种,其中,蓝藻包括铜绿微囊藻（Microcystis aeruginosa）、假鱼腥藻（Pseudanabaenasp．）和束丝藻（Aphanizomenonsp．）,绿藻包括小球藻（Chlorellasp．）以及四尾栅藻（Scenedesmus quadricauda）;基于实测的遥感反射率,经归一化处理后,分析了不同藻种的遥感反射率特征,构建了DI(difference index)指数以及ADI(algae distinguish index)指数,建立了藻种分类模型,利用验证集数据进行检验,整体识别精度达77.55%,Kappa系数为0.7178。将分类方法应用于太湖野外实测遥感反射率数据集中,结果与实测的生物量数据有较好的匹配;将模型应用于太湖OLCI(ocean and land colour instrument)影像数据,获得了2019年12月和2020... 相似文献
19.
Axenic and bacteria-containing assays with the coccal green alga, Scenedesmus subspicatus, were compared with respect to the growth inhibition and promotion, respectively, of one fulvic acid source. In the presence of Fuhrberg fulvic acids, a groundwater fulvic acid from lignite leachate, algal growth was promoted, if bacteria were present. This effect occurred although fulvic acids clearly quenched the available light. We presume that the fulvic acids were utilized by microbes, which, in turn, may have produced and released organic substances, which appeared to be beneficial to the algae. 相似文献
20.
基于突变理论的太湖蓝藻水华危险性分区评价 总被引：7，自引：2，他引：5
蓝藻水华暴发是湖泊生态系统中营养物质长期累积的结果,是系统营养经长期演化后的极端状态.突变理论评价方法无需确定指标权重,减少了人为主观因素,并且计算方便.本文基于突变理论,采取蓝藻水华暴发的表征因子(叶绿素浓度)和导致蓝藻水华暴发的环境因子(总氮和总磷)作为潜在危险性评价指标,蓝藻水华的面积、范围以及暴发频次作为历史危险性评价指标建立多准则蓝藻水华暴发风险评价指标体系,并结合太湖九个分区进行蓝藻水华暴发危险性分区及全湖评价.研究结果表明:竺山湖和西部沿岸为极重危险性湖区;梅梁湾为重度危险性湖区;南部沿岸、贡湖和大太湖为中度危险性湖区;箭湖东茭咀、东太湖和胥湖蓝藻水华暴发危险性较小,为轻微危险性湖区.整体上看,太湖蓝藻水华暴发危险性程度由轻到重基本上沿东南-西北方向变化,与营养盐浓度由低到高分布趋势相一致.根据评价结果,可以明确太湖各区遭遇蓝藻水华暴发危险性的大小,为蓝藻水华风险管理和应急处理提供科学依据. 相似文献