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1.
Paolo Madoni 《Hydrobiologia》1993,264(3):129-135
Ciliated protozoans from sediments of the River Parma (Northern Italy) were collected from 7 stations, selected according to their hydrological, chemical, and physical characteristics, and to river zonation during autumn 1989. Fiftythree species were observed. A saprobic evaluation of the river was made using the taxocenoses observed, and the results were compared with data collected in 1978, when the River Parma still received untreated sewage. In 1989 the hilly section of the stream was found to be more polluted than in 1978, but in the plain section, the saprobic indices were now slightly lower. The marked change in the ciliate community of the hills was accompanied by an increase in organic load, which caused the disappearance of some typical species and dampened the diversifying effects of other environmental factors, producing comparatively similar community structures in that whole zone.  相似文献   

2.
The changes in macrobenthos community depended on changes in stream discharge (from 0.001 m3/sec to 100 m3/sec) were studied on the basis of data from 254 stations of 180 streams located in the centre of European part of Russia. While discharge of stream increases community composition changes considerably. Species diversity increases from 12 to 47 species per station with the increase in stream size. Moreover, the diversity of almost all groups, discerned according habitat or trophic position and main taxonomic groups (with the exception of Plecoptera and Diptera) increases with the increase in stream discharge. The diversity of lithorheophilic species and species inhabiting soft substrates is higher in small streams, whereas phitophilic species are more diverse in large streams. With the increase in stream size the percent of algophagous and filter feeders increases, percent of carnivorous remains the same and the percent of detritophages decreases. The relative role of invertebrates macrotaxons change with the stream size: in the smallest streams the diversity is the highest among Diptera, Trichoptera and Plecoptera, in medium-size streams--among Trichoptera, Ephemeroptera and Diptera, in large streams--in Ephemeroptera, Gastropoda and Trichoptera. In some groups some species replace other (close-related) in parallel with change in stream discharge however in general this tendency is weak. The index of saprobic conditions increases with the increase in stream size from 1.6-1.7 to 2.3-2.4. In small streams the saprobic conditions are very different whereas large streams have tendency to be at beta-mesosaprobic level. Cluster analysis reveal four size classes of streams. Peculiarities of habitat and macrobenthos fauna of these classes are described.  相似文献   

3.
Rotifers as indicators of water quality   总被引:47,自引:10,他引:37  
Six hundred and twenty species and lower taxonomical units of Rotatoria found in Czechoslovakia and surrounding countries are listed alphabetically and classified according to water quality. The numerical characteristics include the saprobic valence in 10 balls, the indicative weight of species, Ii, and the individual saprobic index, Si. Rotifers are considered to be good indicators and some of them are figured on Plates 1–3. The situation is illustrated by four graphs and the relation to BOD5 values is stressed. All rotifers are aerobic organisms and occur only within limnosaprobity. They can also serve as indicators of trophic conditions. To characterize the situation in standing and slowly flowing waters a Brachionus: Trichocerca quotient is proposed. Rotifers can also be used as test organisms in toxicity experiments.  相似文献   

4.
Samples of wild growing ectomycorrhizal and terrestrial saprobic macrofungi (mushrooms) were collected from unpolluted areas and analyzed for their iron, cobalt, zinc and selenium content. Trace elements were determined using long-term instrumental neutron activation analysis. In total, 217 samples, including 87 species of ectomycorrhizal fungi and 43 species of terrestrial saprobes, were examined. Distribution of trace element contents in ectomycorrhizal and saprobic macrofungi was investigated; results are thoroughly compared with previously published data. Doubtful literature data and ability of macrofungi to accumulate/concentrate investigated elements are discussed. Hygrophoropsis aurantiaca was found to concentrate Fe and Russula atropurpurea was confirmed as an effective Zn-accumulating species. Distribution of Se in ectomycorrhizal species was obviously different from that in saprobic species; selenium contents were higher in saprobic species (mostly above 2 ppm).  相似文献   

5.
As anthropogenic N deposition has been suspected to be the main reason for the decline of macromycetous sporocarp production in forest ecosystems, various N-fertilization experiments were started in the mid 1990s. The dynamics of ectomycorrhizal (root-inhabiting) and terricolous saprobic (litter-inhabiting) fungal communities were studied by exhaustive sporocarp inventories in a substitution Norway spruce (Picea abies) forest in two 256-m2 plots sampled for periods of 1 week at 1-m2 resolution between 1994 and 2007. N was added to the soil twice per year in one plot from the fourth year onwards. The effects of N input and time on aboveground fungal communities were assessed using redundancy analysis, principal response curves and non-parametric multivariate ANOVA. Results of this long-term experiment revealed that both ectomycorrhizal and saprobic fungal communities responded to an increase in soil N input. The ectomycorrhizal community reacted by a fast decrease in sporocarp production and in species richness, whereas the saprobic community was less affected. The response was highly species specific, especially for the saprobic community. The difference in species composition between control and fertilized plots was significant after 1 year of N addition for ectomycorrhizal fungi and only after 3 years for saprobic fungi. An aging effect affected sporocarp production in the whole area. For both communities, this unidirectional drift in species composition was as important as the treatment effect. This result highlights the importance of considering the respective role of treatment and year effects in long-term field experiments on fungal communities.  相似文献   

6.
In total 73 species of Euglena were ordered according to their saprobic index (S) and saprobic valency starting with species tolerating a heavy organic pollution and ending with those from most clean water. This paper is meant as an addition to the Ergebnisse der Limnologie, Heft 7 (Sládeek, 1973).  相似文献   

7.
Paulus B  Gadek P  Hyde K 《Mycologia》2004,96(5):1074-1087
During an investigation of saprobic microfungi in leaf litter from an Australian rainforest, five new species of Thozetella, namely T. acerosa, T. boonjiensis, T. falcata, T. gigantea and T. queenslandica, were identified and these are described and illustrated here. The morphology of specimens derived from cultures grown under different conditions and from natural substrata was compared. DNA sequence data of ITS regions within nuclear rDNA confirmed the morphological species concept and indicated that Thozetella species are anamorphs of the ascomycete genus Chaetosphaeria.  相似文献   

8.
The titres of physiological processes in bacteria (hydrolysis of urea, nitrification), total number of bacteria and photosynthesis were found to show high correlation with standard characteristics: BOD5 and saprobic index. The classificatory values of BOD5 and saprobic index depend on the pollution of waters (with BOD5 less than 3 mg O2/l more information on the extent of pollution is given by the saprobic index whereas with higher values BOD5 is better). The content of NH3-N and titres of ammonification and H2S production depend on the type of pollution and should not be used for determination of water purity without additional studies. Of increasing importance as a measure of pollution is the BOD5/BOD2 quotient.  相似文献   

9.
In addition to newly generated and continuously growing datasets in mycological research, existing compilations are of high value to assess the fungi of a whole region. In the present study, a private database with ca. 65,000 entries of macromycetous fruit body observations in Mecklenburg-Western Pomerania, Germany, was analysed. Observed species richness of tree-associated mycorrhizal and saprobic fungi exceeded 3,000 taxa. The total fungal species richness could not be determined with confidence but will possibly exceed 4,000. Distinct species turnover with respect to host trees was observed. However, the rate of community overlap clearly differed between mycorrhizal and saprobic fungi and deciduous and coniferous trees. By separating the data into abundant core species and rare satellite taxa potential indicator species are presented, whose preservation will be beneficial to many other fungi and the entire ecosystems they live in.  相似文献   

10.
The ciliates in aufwuchs communities on glass slides exposed to different amounts of salt pollution at several locations in the Weser River system were investigated. The results were compared with those from the study of model ecosystems exposed to salts. A comparison of the ciliate occurrence with a number of physical and chemical parameters showed that it is primarily the amount of salt present that determines which species are dominant. The number of species present decreases in the presence of high salt concentrations and in water flowing at a high velocity. A halobic index was formulated to indicate salt pollution quantitatively but turned out not to be useful due to the euryhaline potency of most of the ciliate species. The saprobic index can be used in rivers polluted with salt only if biological indicator species are present in sufficient number.  相似文献   

11.
A study of the diversity, taxonomy, and ecology of endophytic Xylariaceae (Ascomycota) was carried out. In this study, we obtained isolates of Xylariaceae from healthy, attached leaves and teleomorphic stromata on decayed plant materials in a permanent plot at Khao Yai National Park (Thailand). In addition, strains deposited beforehand were selected in which both endophytic strains isolated from living plant tissues and saprobic strains from fruit bodies were included. Consequently, 405 strains of Xylariaceae (273 endophytic and 132 saprobic strains, including identified strains) were studied to reveal the diversity and taxonomy of endophytes and the relationships between those endophytes and saprobic Xylariaceae in Thailand that have been recorded according to fruit-body formation on decayed plant materials. Analysis of 28S rDNA D1/D2 sequences revealed 21 xylariaceous species inhabiting tropical foliage at the site, and several species that are already known as saprobes appear to be among those isolated from living leaves. Furthermore, several clades that consisted of only endophytic strains were found, and some of these have no known matches in public DNA sequence banks.  相似文献   

12.
以浮游植物评价达赉湖水质污染及营养水平   总被引:11,自引:0,他引:11  
1987—1988年在30个样点,四季采样,对达赉湖的浮游植物进行了种类组成,生物量、种群数量、优势种、污染指示种、硅藻指数、综合指数等群落生态学的初步研究,应用后五项参数对达赉湖水质污染及营养水平进行了评价。达赉湖浮游植物年均值达54.7×106个/L(细胞数,或个体数为2.3×106个/L),硅藻指数为149.3,综合指数为5.6。群落组成中污染指示种占65%,春季以绿藻的十字藻、卵囊藻为优势种,其它3个季节均以蓝藻中的微囊藻、鱼腥藻、腔球藻占优势,表明达赉湖已受到中等程度污染,属于蓝、绿藻型富营养湖。    相似文献   

13.
Freeze-fracturing of outer wall layers ofCladosporium conidia revealed two types of ultrastructure, coinciding with taxonomic characteristics. The outer conidial layers were essentially smooth in the human pathogenic species,C. bantianum, C. carrionii, andC. trichoides. In contrast, mosaic arrays of rodlets on conidia were observed with freeze-fracturing in the saprobic species,C. cladosporioides, C. coralloides, C. herbarum, C. sphaerospermum, andC. variabile. Conidia ofC. elatum were an exception among the saprobic species as they had smooth surfaces. The present study supports the suggestion that the human pathogenicCladosporium species should be transferred to another genus.  相似文献   

14.
In the periphyton of the Samarga River basin, 313 species of algae (337, including infraspecific taxa) from eight divisions have been found. The groups of algae from the river main flow, creeks, streams, and the mouth are described. Data on the density and biomass of periphyton algae are presented. A decrease in these parameters after a flood is shown. In algal flora composition, benthic oligohalobic species of algae, preferring a slightly alkaline environment, dominate. At the river mouth a significant amount of mesohalobic species has been observed. A sanitary and biological evaluation of water quality has shown that the mass development of xenoand oligosaprobic algae defines the excellent quality of the river water. All parts of the main flow correspond to the oligosaprobic purification zone, class II of water purity (saprobic index of 0.95–1.48). The good quality of the Samarga River water is ensured by the absence of pollution sources and the satisfactory condition of its catchment area forests.  相似文献   

15.
16.
Lubor Simanov 《Hydrobiologia》1975,47(3-4):453-462
On the basis of a rich material of larvae and pupae of caddis-flies collected in two south-moravian rivulets Jihlava and Bobrava, the methods of estimation of saprobity used in Czechoslovakia were compared. These were the methods of saprobic valency by Zelinka & Marvan (1961) complemented by the saprobic index Sr of Rothschein (1959), saprobic index according to Pantle & Buck (1955) and a method by Obr (1956). The locality on the Jihlava rivulet near Iváň was considered as epipotamon, the locality on the Bobrava rivulet near Želešice was taken as hyporhitron in the sense of the biocoenotical classification of Illies & Botosaneanu (1963). The most common Trichoptera are shown on Figs. 1 and 2. The procedure of estimation is presented in Tab. 1–6, that of comparison in Tab. 7. By all methods applied it was demonstrated that the Jihlava rivulet is beta-mesosaprobic and the Bobrava rivulet in the transition between oligosaprobity to beta-mesosaprobity. All methods are leading to nearly identical results, but the method of saprobic valency gives the most exact numbers and in connection with the index SR enables a graphical presentation. The method of Pantle & Buck is less precise, but quicker with the possibility of immediate graphical presentation. The author presumes that it is possible to estimate the saprobity according to one dominant group of organisms, if the investigation is long-termed and if there are enough species with a known saprobic valency.  相似文献   

17.
The genus Cladophialophora comprises etiologic agents of disease in immunocompetent patients, ranging from mild cutaneous colonization to cerebral encephalitis, in addition to saprobic species. Due to the high degree of phenotypic similarity between closely related species of the genus, identification problems are imminent. In the present study, we described rapid and sensitive rolling circle amplification (RCA) method based on species-specific padlock probes targeted for the internal transcribed spacer regions of rDNA. ITS regions of 12 Cladophialophora species were sequenced, and subsequently, 10 specific padlock probes were designed for the detection of single nucleotide polymorphisms. The majority of circularizable padlock probes were designed based on single nucleotide polymorphisms (SNPs), while for C. bantiana, C. immunda and C. devriesii were characterized by two or more nucleotides. Individual species-specific probes correctly identified in all ten Cladophialophora species correctly by visualization on 1.2 % agarose gels used to verify specificity of probe-template binding; no cross-reactivity was observed. Simplicity, sensitivity, robustness and low costs provide RCA a distinct place among isothermal techniques for DNA diagnostics. However, restriction and specificity and sensitivity should be lowered and increased, respectively, to be useful for a wide variety of clinical applications.  相似文献   

18.
19.
Rolauffs  Peter  Stubauer  Ilse  Zahrádková  Svetlana  Brabec  Karel  Moog  Otto 《Hydrobiologia》2004,516(1-3):285-298
The use of saprobic systems has long traditions in the water management in Austria, the Czech Republic and Germany. Within the context of water quality assessment they are applied to indicate the effects of anthropogenic caused organic impact leading to a decrease in the dissolved oxygen content of running waters. In December 2000 the European Union Water Framework Directive (WFD) came into force. It demands homogeneous procedures and methods for assessing inland surface waters as well as groundwater, coastal and transitional waters. The WFD focuses on the assessment of biotic elements and the ecological status has to be defined based on type specific approaches and reference conditions. To incorporate the saprobic approach into the new integrative methodology of the European assessment of the ecological status of water bodies, the national saprobic systems need to be adjusted. This paper describes the according methodological developments and adaptations of Austria, the Czech Republic, and Germany required to harmonise the traditional procedure with the guidelines of the WFD. In the three countries national databases were established to provide species lists from largely undisturbed stream sites. Such reference sites build the basis for calculating stream type specific reference values. The calculation has been done in slightly different ways dependent on the country. In addition to that boundaries were defined to characterise the 5 saprobic quality classes.  相似文献   

20.
We conducted line route censuses of fungal fruiting bodies from August to September in 2005 and 2006 along ridges and valleys and compared the differences in the encounter rates of fungal fruiting bodies (= fruiting bodies seen per census kilometer) between types of topography and between fungal functional groups (i.e., ectomycorrhizal and saprobic fungi) in warm temperate evergreen broad-leaved forests on Yakushima Island, Japan. We found 251 fungal fruiting bodies (26 families, 50 genera, and 65 species) in total, including 51 bodies from Tricholomataceae, 41 from Russulaceae, 25 from Boletaceae, and 19 from Amanitaceae. The encounter rate of ectomycorrhizal fungi was greater at the ridge route (26.7 unit/km) than at the valley route (8.7 unit/km) and that of saprobic fungi was greater at the valley route (25.0 unit/km) than at the ridge route (12.5 unit/km). In addition, we conducted 7-year intermittent sampling and identified 40 families, 96 genera, and 142 species. The topography-specific emergence pattern of the intermittent sampling method was similar to that of the line census method. The fungal species composition in this study was possibly affected by a topographic gradient for both fungal functional groups through soil moisture, nutrient availability, and host tree distribution.  相似文献   

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