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Effect of ponds and pond systems on the composition of the benthos in horní Lužnice
SVAČINA, Petr
The work is focused on monitoring changes in benthic communities in the longitudinal gradient of the river Lužnice. The river flows through to the pond area Třeboňsko and the largest pond of the Czech Republic - Rožmberk. It is examine affect of pond on benthic communities. The work involves collecting benthos according to the PERLA method on four profile in four seasons, the analysis of chemical parameters and data processing. The values of SI (saprobiological index) in the longitudinal gradient were from SI 1.8 to SI 2.6. SI values were at the outflow of Rožmberk higher than at inflow. The lowest values were in the first profile Suchdol (SI 1,8 ? SI 2,1) and higher values were in the last profile Vlkov (SI 2,4 ? 2,6). The chemical parameters at outflow were observed increased values of BOD5, TOC, NL105, NL505, chlorophyll and total P but lower values of nitrogen forms (Ntotal,NH4, N-NO3-). On the each profile was the significant change in the incidence or absence of certain groups. Profiles Suchdol and Hlína were diferent than Lužnice and Vlkov especially in the presence of stoneflies, dragonflies, beetles, and individuals generally indicates good water quality. Profiles at outflows from Rožmberk (Lužnice and Vlkov) showed a continued presence of bloodsuckers and more species indicating high organic pollution. NMDS method confirmed impact of sites in communities rather than period (R2 = 0.6 at significance level of p = 0.001).
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Evaluation of quality and the renewal of surface water in the area affected by surface coal mining.
VLÁŠEK, Ondřej
The aim of the study was to evaluate the parameters of quality and renewal of surface water in the area affected by surface brown-coal mining. Selected streams were monitored on the Great pokrusnohorska dump, and streams unaffected by dumps. Values of pH, conductivity, alkalinity, oxygen saturation and temperature were measured, and quantitative and qualitative samples of macrozoobethos were taken too. The dump?s water are characterized by high concentrations of dissolved solids and alkalinity. Species diverzity of these waters is lower and is affected not only by chemical compositon of the water, but also by the character of the bottom substrate.
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Seasonal changes in macrozoobenthos of the Brno reservoir during water level manipulation
OPATŘIL, Jan
There is a number of measures, which have been currently performed on the Brno Reservoir, with the aim at the recovery of the environment health and at the reduction of incidence of cyanobacterial water blooms. The main intervention in this efforts was the desrease of water level in 2009-2010, when the level was reduced by up to 9 m. This intervention resulted in drying of the uncovered area of the littoral bottom and in completely changed oxygen conditions in the remaining lake. The objective of my work is to evaluate changes in benthic macroinvertebrate assemblage in response to these interventions and measures. On the sites of the reservoir, selected with respect to water levels and in-depth ratios, macroinvertebrates were seasonally sampled by the Ekman grab and kick-off approach in deep muddy sites and in the littoral zone, resepctively. Samples were collected at the ?Hráz?, ?Střed?, ?Litorál?, ?Rakovec?, ?Zouvalka?, ?Rokle? and ?Horní vzdutí?. In parallel with sampling selected environmental parameters (temperature, O2) in epilimnium hypolimnium were measured. The samples were washed and conserved for later determination and quantification in the laboratory. All macroinvertebrate samples were divided into three groups: Chironomidae, Oligochaeta and Others. The result are presented in a graphical form as the biomass and density on different sites according to the years preceding the reservoir draining, during the water level decline and afterwards and discussed in association with certain abiotic factors.
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Species variability of bentic organisms in Dračice river classicifed by PERLA system
KOUTNIK, Dalibor
Examination ecological size selected part of river (from village Františkov to border with Austria) on the basis of field watching. Observed results are analysed by system PERLA. Method is based on analysing biodiversity makrozoobenthos sample from fordables running water. Sampling can be apply in running water, where water column not exceed 1 m and speed of water stream to 1 m/s. Taking is made by normal or low water stage.
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Effect of electrofishing on macrozoobenthos
PAVLÍČEK, Michal
Experiment has been addicted for observing effect of electrofishing on macrozoobenthos including mechanical stimulus (passing of trawling squad). Reaction on electrofishing and fading has been rebound by drift increment. Sample taking had been done by use of Surber and drift nets. Evaluation has been made both quantitative (standing crop in drift in particular methods), and qualitative (substitution of taxons in particular methods).
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The application of artificial substrates for quantitative and qualitative study of macrozoobenthos.
MAČEJ, Jakub
Macrozoobenthos are aquatic invertebrates, usually bigger than approximately 2 mm, living on the bottom. The larvae of aquatic insects (mayflies, midges, caddisflies, etc.), worms, molluscs and crustaceans belong among its most important representatives. The study was performed on a pond channel of the experimental pond system of the FFPW Vodnany. The artificial substrates, made of plastic blocks from biological filters, were installed in five rows of five blocks (replications) to monitor the process of their colonization in order to evaluate their suitability for the monitoring of macrozoobenthos. At weekly intervals, one series of five artificial substrates was sampled to collect colonizing macroinvertebrates for further elaboration (determination, numbers). It was confirmed that under the conditions of a pond canal, the colonization of artificial substrates by benthic animals begins immediately during the first week of their deployment. Species diversity of macrozoobenthos, expressed in number of taxa in successive weeks afterwards was not significantly different. The results proved that artificial substrates are suitable for quantitative and qualitative monitoring of benthic macroinvertebrate assemblage.
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Macrozoobenthos of the Pohořský and Dobechovský brooks in the Novohradské hory Mts.
KLOUDOVÁ, Jana
The presented thesis deals with the structure and composition of macrozoobenthos of Pohořský and Dobechovský brooks in the Novohradské Mountains. The evaluation was based on the collections from 10 localities carried out in July 2001, March 2002 and July 2002/2003. In addition to determination and classification of the species found, the collections have also been qualitatively evaluated with the use of the diversity index (saprobic index, Belgian Biotic index) and the similarity index. It has been found that the zoobenthos population of Pohořský and Dobechovský brooks encompasses the species of both trout and grayling zones. In most taxa it concerns characteristic representatives of clear, flowing and adequately aerated water. Mutual species similarity of macrozoobenthos population of Pohořský and Dobechovský brooks is approximately 40%. The comparison of macrozoobenthos population diversity indices of Pohořský and Dobechovský brooks has shown that the Pohořský brook bentic fauna is, according to the obtained data, richer and better balanced. From the saprobity point of view, the Pohořský brook can mainly be placed into oligosaprobic stream class. The water of Dobechovský brook oscillates between oligosaprobic and {$\beta$}-mesosaprobic level.
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