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Společenstva vodních makrobezobratlých ovlivněna lidskými činnostmi
LET, Marek
Macroinvertebrates represent an essential part of aquatic environments contributing to various ecosystem services. Disregarding the importance of their habitats and stable and functionally diverse communities can cause hardly reversible losses. This Thesis aimed to reveal relationships between responses of aquatic macroinvertebrate communities and the consequences of human activities. The general negative relationship between the gradient of insecticide contamination and abundances of higher taxonomic units of the stream macroinvertebrates was observed (Chapter 2). The gradient of droughts correlated negatively to the abundances of mayflies (Ephemeroptera), stoneflies (Plecoptera) and caddisflies (Trichoptera) - hereinafter referred as "EPT" - and the most positively to the abundances of coleopteran adults, heteropterans, ostracods, and water lice. Disturbing synergic effects of droughts and agricultural runoff were assumed based on the comparisons between communities sampled in the control site and initially contaminated downstream sites. The practices in modern agricultural systems can be considered one of the greatest threats to aquatic macroinvertebrate fauna. Results summarised in Chapter 3 show decreasing richness of EPT taxa (however, not their abundances) along with the involvement of an increasing number of anthropogenic factors. Nevertheless, only the mayflies and especially stoneflies showed significant negative responses, whilst caddisflies generally exhibited resistance to the presumably strongest anthropogenic factors; namely to contamination by trace metals (cadmium, lead and zinc) and to subsequent loads of treated and "poorly treated" municipal wastewaters containing pesticides, pharmaceutical active compounds, sewage-derived organic matter, and undoubtedly other not identified kinds of pollutants. Despite the higher caddisfly abundance, there were detected signs of worsened health status in hydropsychids, limnephilids and rhyacophilids, particularly detected malformations and the presence of dead pupae in both types of contaminated environments. However, the environment polluted by wastewaters exhibited a significant relationship to a highly increased relative contribution of passive filter feeders and predators within the EPT community. Since wastewater treatment technologies have been enhanced in many countries and there is a lack of published evidence about their complex effect on aquatic ecosystems, future studies are required. Chapter 4 reveals the negative effect of non-native signal crayfish (Pacifastacus leniusculus) on the native branchiodellid community. According to our results, the total replacement of the native noble crayfish (Astacus astacus) by signal crayfish can lead to the disappearance of two species Branchiobdella parasita and B. pentadonta. Potential differences between crayfish species in correlations between abundances of both branchiobdellids were observed in the locality with the sympatric occurrence of noble crayfish and signal crayfish; the abundance of bigger-sized B. parasita positively correlated to the abundance of B. pentadonta only in the signal crayfish, whilst this relationship may be negative in the big-sized noble crayfish densely infested by both species. Potential competition for space was assumed. The experiment in laboratory conditions revealed more intensive grooming in signal crayfish. The results demonstrate the loss of overlooked biodiversity associated with the invasive species introduction. Knowledge of how communities of aquatic invertebrates respond to anthropogenic changes in the environment can be useful, e.g., during the assessment of the implications of planned or currently active human interferences for cultural landscapes. This Thesis will provide useful information for laboratory studies, of which the interpretation is often limited as they are carried out in artificial environments.
Bioaccumulation of heavy metals in macroinvertebrates: relationship between concentrations and organism size
Hanzlíková, Lenka ; Dočkalová, Kateřina (advisor) ; Hořická, Zuzana (referee)
The size of benthic organisms is one of many possible factors affecting resultant concentrations of metals accumulated in organisms from surrounding water environment. Partial information is presented in research publications which state this dependency with different conclusions. So far the dependence was not unequivocally interpreted. Relationship between concentration and body size may differ among various metals and also between individual species of macroinvertebrates. This bachelor thesis is a research of professional literature and its result is analysis of existing knowledge of types of this dependancy and comparison of individual representatives of aquatic invertebrates and individual metals. Significance of the trend of dependence as a factor having the influence on the final interpretation of data on the concentrations of monitored substances, especially heavy metals is to be assessed. Result of this work should facilitate the interpretation of data for future analysis of heavymetals in aquatic invertebrate organisms. Keywords: bioaccumulation, heavy metals, macroinvertebrates
The impact of vertical distribution of zoobenthos in a pond in response to the biomass stocking of carp ponds
VÁLEK, Pavel
The impact of vertical distribution of zoobenthos in a pond in response to the biomass stocking of carp ponds was tested in the Rod, Dobrá Vůle, Pohořelec, Haslauerteich and Neuteich ponds. Except for the Rod pond, various carp biomass was represented in all ponds. Sampling was conducted during the growing season (June and July), and outside the growing season (September). Physico-chemical parameters of water were measured for each sample. All samples were sorted by groups, counted and weighed. The results are presented in graphs. Zoobenthos density of the Dobrá Vůle, Haslauerteich and Neuteich ponds showed a rising tendency towards deeper parts of the pond sediment. The density of these ponds reached the maximum values in depths of 10-14 cm. This tendency was observed in the occurrence of midges in these ponds. The highest density of midges was observed in the Haslauerteich pond (1,687 individuals per square metre). The above-mentioned ponds were stocked by the common carp (K2-3). The largest density of the tubifexes in the Dobrá Vůle, Haslauerteich and Neuteich ponds was observed during the September sampling in the shallow parts of the sediment (0-6 cm). The maximum density was 1,031 individuals per square metre. On the Pohořelec pond, the occurrence of zoobenthos during both samplings was recorded only in the depth of 10-12 cm. Other representatives of zoobenthos were present in the Rod, Haslauerteich and Neuteich ponds. Larvae of Sialis and Chaoboridae were observed as well. The density and biomass was greater in the September sampling. We have noticed a greater settlement in various depths. Their maximum density was in the Haslauerteich pond (218 individuals per square metre).
Diverzita makrozoobentosu v Evropsky významné lokalitě výskytu raka kamenáče (Austropotamobius torrentium)
PEŘINOVÁ, Eliška
The "Zákolanský potok" takes part in European nature program Special Area of Conservation because of the presence of stone crayfish (Austropotamobius torentium), which is listed as threatened species. The area around brook is intensively agriculturally cultivated. Water from wastewater treatments plants is drained to the local brooks. The aim of the work was to describe diversity of macrozoobenthos on the brook called "Zákolanský potok". Further aim was to evaluate the ecological condition of the watercourse using biotic indexes. The samples of macrobenthos were taken from three profiles in five sampling periods. Profile 1 was control, profile 2 was under the wastewater treatments plants and the third profile was placed down the stream. Diversity, biomass, saprobic index, BMWP, and ASTP scores were evaluated for the community of macrozoobenthos. The saprobic index was evaluated to the beta-mezosaprobity value (2.0-2.4) in the first profile, the saprobic index on the second profile showed a relatively wide range from worse oligosaprobity to worse beta-mesosaprobity (1.2-2.4). On the third profile, the saprobic index ranged from better beta-mesosaprobity to better alpha-mesosaprobity (1.6-2.6). The BMWP and ASPT scores in all profiles refer to medium to low quality aquatic environments. The diversity of the community gained the best values on the 3rd profile, here was found with one more taxon than on the 1st profile. With increasing organic load, diversity decreased on the 2nd profile, although a more sensitive species was found here.
The impact of vertical distribution of zoobenthos in a pond in response to the biomass stocking of carp ponds
VÁLEK, Pavel
The impact of vertical distribution of zoobenthos in a pond in response to the biomass stocking of carp ponds was tested in the Rod, Dobrá Vůle, Pohořelec, Haslauerteich and Neuteich ponds. Except for the Rod pond, various carp biomass was represented in all ponds. Sampling was conducted during the growing season (June and July), and outside the growing season (September). Physico-chemical parameters of water were measured for each sample. All samples were sorted by groups, counted and weighed. The results are presented in graphs. Zoobenthos density of the Dobrá Vůle, Haslauerteich and Neuteich ponds showed a rising tendency towards deeper parts of the pond sediment. The density of these ponds reached the maximum values in depths of 10-14 cm. This tendency was observed in the occurrence of midges in these ponds. The highest density of midges was observed in the Haslauerteich pond (1,687 individuals per square metre). The above-mentioned ponds were stocked by the common carp (K2-3). The largest density of the tubifexes in the Dobrá Vůle, Haslauerteich and Neuteich ponds was observed during the September sampling in the shallow parts of the sediment (0-6 cm). The maximum density was 1,031 individuals per square metre. On the Pohořelec pond, the occurrence of zoobenthos during both samplings was recorded only in the depth of 10-12 cm. Other representatives of zoobenthos were present in the Rod, Haslauerteich and Neuteich ponds. Larvae of Sialis and Chaoboridae were observed as well. The density and biomass was greater in the September sampling. We have noticed a greater settlement in various depths. Their maximum density was in the Haslauerteich pond (218 individuals per square metre).
Assessment of macroinvertebrates diversity in contex of physical river habitat quality
Nováková, Barbora ; Matoušková, Milada (advisor) ; Havlíková, Petra (referee)
Research of macroinvertebrates is currently an important part of the assessment of stream quality. Basic characteristics influencing macroinvertebrates communities in the streams are elements from the external environment influencing streams, specifically basic geographic parameters of the site, land-use in the catchment and characteristics of the banks. These elements have a considerable influence on effect of the basic parameters in the stream, which are flow, sediment structure, input of organic material and pollution. Research part of the thesis is about the parameters influencing macroinvertebrates communities. Research area of this work includes three different catchments in the upper part of Blanice catchment area near Prachtice. There is one nature stream with forest in it's catchment, stream with a predominantly meadow basin and last stream is characterized by two distinct stretches - a revitalized section and a section with concrete bottom. The subject of this diploma thesis is evaluation of diversity of macroinvertebrates communities in all streams in the research area. Thesis evaluate communities of macroinvertebrate using a wide range of indexes (BMWP score, ASTP index, EPT index a diversity indexes) and compares their diversity by using rank-abundance graph. All results are summarized...
Makrozoobentos zarostlého a volného bahnitého litorálu kaprových rybníků
KAJGROVÁ, Lenka
The aim of the study was to evaluate the quantitative composition of benthic invertebrates in the littoral zone with emeragent plants and outside the macrophyte beds. For these purposes, two carp ongrowing ponds were selected in the Czech Republic (Blatná region) with traditional carp (Cyprinus carpio) farming and two organic ponds in Austria (Waldviertel). Samplings were performed in monthly intervals (May - September 2018). Samples were taken from the area of open water (pelagial) and from the littoral zone. The evaluation of benthic macroinvertebrates was supplemented by in-situ monitoring of basic parameters of the aquatic environment, granulometric score and rating of organic substances in the bottom sediment of ponds, both in the pelagic and littoral zone. For the sampling of pond macroinvertebrates associated with the root system of the hard emergent vegetation, a core sampler was chosen that penetrates the roots of hard littoral vegetation. After the samples were processed (collection and weighing) in the laboratory, the organisms were divided into three groups - Chironomidae, Oligochaeta and Varia. The results were presented in graphical form. Regarding results of environmental conditions of the studied ponds, they did not differ significantly. According to the analysis of the data, macroinvertebrates density was higher in organic fish farming ponds than in traditional fish farming ponds. In the litoral zone, the average density of benthic invertebrates was higher than in the pelagiac zone. The biomass of aquatic macroinvertebrates on average was also higher in the littoral zone.
Vliv vypouštění oteplených vod na makrozoobentos malého toku
Voltemar, Erik
Bachelor thesis is focused on the theme: Effects of discharge of heated water to macrozoobentos of small stream. The aim of this thesis was to develop literature search on the impact of thermal pollution on aquatic ecosystems and temperature tolerance of aquatic invertebrates. For purposes of practical studies were selected four streams in the vicinity of nuclear power plant Dukovany. For complex results were streams observed during the autumn 2013 and spring 2014. At affected Skryjský stream were selected four sampling sites SP0-SP3 for objective monitoring. Locations LIP, HER and LUHY, were not directly affected by the warmed wastewater from nuclear powerplant and serve as comparison sites. At all locations were conducted multi habitat samplings by method PERLA. At the same time they were measured basic physical and chemical parameters and collected samples for determination of basic chemical parameters. From results was determined abundance, taxonomic composition, diversity and functional structure of water macroinvertebrates. At the same time were also evaluated differences in the composition of communities in influenced and reference streams. Results shows that the heated water from the nuclear powerplant have a significant impact on reducing makrozoobentos at Skryjský stream. Due to high temperature and conductivity of waste waters in autum 2013 and spring 2014 were abundance and taxonomic composition at Skryjský stream significantly reduced. At locations LUHY, LIP and HER were not identified adverse effects of the discharge of heated water from nuclear powerplant.
The load of sediments and bentic organisms with trace metals in urban stream Botič
Hanzlíková, Lenka ; Dočkalová, Kateřina (advisor) ; Stuchlík, Evžen (referee)
Trace element bioaccumulation in benthic organisms is important part of aquatic environment pollution research, since water and sediment analysis itselfs do not provide significant information about bioavailability of contaminants and the results mostly shows just current pollution at the time of sampling. This study focuses on urban streams contamination which are currently significant source of trace elements. Botic stream was chosen as exemplary, because it is affected by many combined sewer system overflows which are sources of contamination in times of heavy rain and flood. Load several sampling took place on 10 stream sites during the year of 2012. This thesis deals with 11 trace elements concretelly Cd, Co, Cr, Cu, Hg, Ni, Zn, As, Fe, Pb and Al. Trace elements were assessed in both benthic organisms and sediment. As well taxons were selected from benthic organisms, which are widely found at any time of the reference year: caddisflies of family Hydropsychidae, leeches Erpobdella sp. and mayflies of Baetidae family. Sediment analysis included sequential extraction which divided trace elements into 4 fractions according to mobility. Based on the results, bioavailability was assessed on observed elements and correlation between concentration in bethos and sediment was tested. Finally, impact of...
Freshwater macroinvertebrates and their use for assessment of environmental changes in running waters
Kolaříková, Kateřina ; Stuchlík, Evžen (advisor) ; Matěna, Josef (referee) ; Porcal, Petr (referee)
The dissertation thesis consists of five articles, bringing together results from investigations of macroinvertebrates in running waters. The use of freshwater macroinvertebrate organisms to assess environmental changes was based on the following facts: a) the presence/absence of taxa provide information about abiotic factors and/or about the pollution status of the site, b) they are indigenous and sedentary species, so that the environmental implications can be related to the site they live on, c) the organisms accumulate xenobiotic elements or compounds, thus reflecting the contaminant level in the environment. Localization of the sampling sites was related to the "hot-spots" of environmental problems. The particular investigations were carried out in the Elbe River catchment and in the Czech mountains on the selected headwater streams of the GEOMON network of the Czech Geological Survey. The Elbe was considered one of the most polluted rivers across Europe in the second half of the past century until the socio-economic transformation after 1989. The headwater streams in the Czech Republic were chosen with respect to the problem of acidification. The ability of bioaccumulation of xenobiotics in macroinvertebrate organisms was used to assess the long-term load of the Elbe ecosystem with trace...

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