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1.
九脊游仆虫(Euplotes novemcarinata Wang、1930)是土壤及淡水中生活的原生动物。本文对其重要的分类特征诸如银线系及纤毛下器做了形态学研究,确认了其分类地位,并比较了国外迄今的研究工作,在此基础上,将同物异名苔藓游仆虫(E.muscicolaKahl、1932)作了归并。  相似文献   
2.
The objective of the present survey was to assess the microbiological quality of river waters used mainly to irrigate the large plains of Macedonia and Thessaly in Northern Greece. Five rivers (Aliakmonas, Axios, Loudias, Mavroneri and Pineios) were sampled during a 10‐month period (June 2002 – March 2003) for Total Microbial Flora (TMF) at 22 °C and 37 °C, Total Coliforms (TC), Fecal Coliforms (FC), enterococci, staphylococci, Pseudomonas, fungi, Giardia spp. and Cryptosporidium spp. The results indicate moderate to high microbiological pollution, with the highest levels of microbial pollution found in Mavroneri and Pineios Rivers, and moderate pollution levels in Aliakmonas, Axios and Loudias Rivers. The extent of microbiological pollution is accentuated by the fact that Giardia‐ and/or Cryptosporidium cysts were detected in nine out of eleven samples collected in June 2002 with excessive Giardia counts demonstrated for Pineios River. The microbiological pollution of the surveyed rivers is attributed to various degrees of human interference and to lack of ample pollution monitoring systems, which emphasize the need for implementation of the EU Water Framework Directive.  相似文献   
3.
Cryptosporidium is an enteric parasitic protozoan capable of causing chronic diarrhea. One of the most common modes of transmission is through faeces‐contaminated water. This study determines the distribution of Cryptosporidium oocysts for the first time in Chennai City's drinking water supply. 199 drinking water samples were collected from ten zones of the city. In the water samples Cryptosporidium, a common pathogenic protozoan of the gastrointestinal tract, has been analyzed physico chemically as well as microbiologically for heterotrophic organisms and total coliforms (TC). The studies revealed that three zones of the city were highly contaminated with coliforms and parasitic protozoa. A statistical analysis was done to find any correlation between heterotrophic organisms, total coliforms, and oocysts. Even though a positive correlation exists between oocysts and bacteriological parameters, a regression equation shows that heterotrophic plate count (HPC) and total coliforms were only 20% responsible for the presence of oocysts. The level of Cryptosporidium oocysts isolated from the water samples may present a public health hazard although no major outbreaks have so far been reported in Chennai City. Routine surveillance of water quality throughout the city is needed to curb the pollutants.  相似文献   
4.
Structural and functional parameters of protozoan communities were assessed as indicators of water quality in Korean coastal waters in the summer of 2000. A modified polyurethane foam unit (PFU) method, named the bottled PFU (BPFU) system, was used in order to carry out the bioassessment. Both parameters suggested that biomonitoring using the BPFU system was more effective than the conventional PFU method in offshore areas. The species number collected by the BPFU system generally decreased as pollution intensity increased at three main stations and was greater than that collected using the PFU method (paired t-test, t = 4.83, p < 0.0001). The Margalef diversity index coincided well with the water conditions. The diversity index values calculated from the BPFU system were also significantly higher than those from the PFU method (paired t-test, t = 5.37, p < 0.0001). Furthermore, the functional parameters, i.e. S(eq),G and T90%, correlated with the pollution status and could thus clearly discriminate the different classes of water quality.  相似文献   
5.
An understanding of the dynamic relationship between nitrogen supply and the formation of phytoplankton biomass is important in predicting and avoiding marine eutrophication. This relationship can be expressed as the short-term yield q of chlorophyll from dissolved available inorganic nitrogen (DAIN), the sum of nitrate, nitrite and ammonium. This paper communicates the results of a continuous culture nitrate enrichment experiment undertaken to investigate the cumulative yield of chlorophyll from DAIN (q). The purposes of the study were: to acquire a better understanding of the relationship between chlorophyll formation and DAIN; to obtain values that could be used in models for predicting eutrophication. The results of a time series experiment carried out using microplankton (all organisms <200 μm in size) indicate that the parameter q does not have a single value but is affected by the ecophysiological response of phytoplankton to changing nutrient status after an enrichment event. It is also dependent on changes in the allocation of nitrogen between autotrophs and heterotrophs. The value of yield obtained at the height of the bloom can be represented by q (max) (2.35 μg chl (μmol N)−1). The post-bloom, steady state value of q can be represented by qeq (0.95 μg chl (μmol N)−1). The microcosm steady state yield was not significantly different from the median value obtained from synoptic studies of Scottish west coast waters. It is proposed that qeq is the most appropriate value for assessing the general potential for eutrophication resulting from continuous nutrient enrichment into coastal waters. It is further proposed that q (max) be used for cases of sporadic enrichment and where a short burst of unrestricted growth may be detrimental.  相似文献   
6.
INTRODUCTIONJohannes (1 965)firstshowedtheimportanceofprotozoaasremineralizersinmarineenvironments.Thesignificanceofprotozoainthefreshwaterfoodwebhasbeenknownforthepast2 0years.Protozoaisamainpredatorofplanktonicbacteriaandphytoplankton ,andalsoafoodsourceo…  相似文献   
7.
德国柏林市Stechlin湖原生动物群落多样性特征的初步研究   总被引:10,自引:0,他引:10  
本文报道了作者在1994年秋季至1995年冬季利用PFU(Polyurethane Unit Foarm,聚氨酯泡沫塑料块)人工基质和结合传统的采集自然基质方法研究德国柏林市郊Stechlin湖原生动物群落多样性特征的结果,通过连续采样调查,首次记录了该湖128种原生动物,实验结果表明:在相同采样时间内,3个不同生境类型的采样站PFU原生动物的群集速度及个体丰度存在明显差异;在相同采样时间和地点,PFU人工基质能够采集到比自然基质更为多的原生动物种类,从而进一步证实了PFU方法应用在原生动物群落多样性研究上的优势作用。  相似文献   
8.
INTRODUCTIONCiliates,alwaysdominatingalltheprotozoans,arethecommonandimportantmembersoffreshwaterzooplanktoncommunities.Asmainconsumersofbacteria,picoplanktonandnannoplankton(Finlay,1978;Porteretal.,1985;Taylor,1984,1987;Simeketal.,1996)compriseanimportanttrophiclinka…  相似文献   
9.
纤毛虫原生动物的细胞发生模式研究--多样性与新进展   总被引:3,自引:0,他引:3  
本文以纤毛门腹毛亚纲内两个目(游仆目、腹毛目)之部分代表性阶元为例,介绍了该大类高度分化的原生动物在细胞分裂过程中皮膜、纤毛器、核器的发生、演化模式以及基本规律,这些工作涉及纤毛虫口器发生中表层与深层远生型等不同亚型类群在无性分裂中皮膜结构的分化模式与发生学,包括对各相关类群特殊发生型的介绍以及对作者等所揭示的部分新发现等内容的报道。文中同时对纤毛虫细胞发生学与系统学研究间的关系、意义、目前所存在的若干未明和热点问题以及发生学资讯与当今其它系统学研究方法的互补与拟和问题做了归纳性讨论和表述。  相似文献   
10.
共栖于对虾体表的致病性纤毛虫Ⅰ.(纤毛动物门,缘毛目)   总被引:1,自引:0,他引:1  
采用现代通行的蛋白银染色法及Foissner干银法对共栖在对虾体表的钟虫属11种致病性纤毛虫做了形态分类学研究。报道了5种国内新记录。对所涉种类的银线系及纤毛下器做了首次揭示与描述,并列表对诸种的分类特征进行了统计学界定。  相似文献   
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