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Břehové a doprovodné dřevinné porosty vodních toků
Kováčová, Dominika
The first part of this Bachelor's thesis discussed the issue of vegetation along the river margins and banks according to the recommended literature. The literature re-search, based on the information obtained, dealt with the primary functions of wetlands and riparian vegetation. It also described individual parts (zones) of riverbed. In conclusion, the research covered the issue of riparian vegetation establishment and management. The second part contained the methodology, used in this thesis, basic characteris-tics of the river Jizera and a description of chosen areas. The area of interest was divided into seven parts, which were explored and described in detail in terms of plant species and their locations. The restoration and management plan was made based on results found.
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Ichthyofauna of selected sections of the Jizera basin
CHYTRÝ, Martin
Rivers fragmentation by migration barriers has a significant negative effect on native fish communities and other river organisms. That is the reason why there has been put a lot of emphasis on creating fish pass in rivers in recent years. Between the years 2012 and 2013 there were carried out investigations on the new slit fish pass on the Jizera River in Turnov. The aim was to assess the technical realization of the construction of fish pass and functionality for local ichthyofauna. Primarily we have focused on hydraulic conditions in the fish pass (water flow, velocity, level differences in all chambers). During the fish pass technical inspection the fish was being caught by electric aggregate. The species composition of fish was also measured in the weir. Catching weir was used to catch the counter-migrating fish through the fish pass. The caught fish was taken its body length in mm and weight in grams and subsequently was calculated numerical dominance, diversity and evenness. There were 519 pieces of fish caught weighing 6.395 kg in total. There was confirmed presence of 10 species of fish in the fish pass, while in the weir were found 3 more species of fish and 1 species of lamprey. Reproductive migration was confirmed for brown trout and minnow. Roach, dace, perch and chub have settled down in the resting chambers permanently. There have been found several defects in the fish pass. There have been found large differences between the levels of chambers, high flow rates, reduced light penetration of the water in the fish pass, lack of entry attractiveness of the fish pass and non-minimum residual flows. Fish passage is considerably clogged by suspended dirt and the cleaning possibility is limited. Functionality and selectivity of the fish passage has not been demonstrated. There will be further investigations carried out in 2013.
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