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Stanovení vzorců selektivního chování rybářů ve statistikách českého rekreačního rybolovu
Jankovský, Martin ; Pivnička, Karel (advisor) ; Slavík, Ondřej (referee) ; Adámek, Martin (referee)
Methods for detecting patterns of angler selective fishing behaviour in the long term recreational fishery statistics are presented in this Ph.D. Thesis. The motivating idea is that mainly different anglers' fishing preferences or attitudes towards particular fish species obstruct applying anglers' catches data for ongoing use in ichthyology research. Better recognising angler selectivity is therefore judged to be the key point from the viewpoint of fish and fishery sciences. Methods affecting angler behaviour can be directly applied by other specialists, e.g. social scientists. The thesis consists of five papers two of which are published (paper 1, 2), other two of which are accepted for publishing (paper 3, 4) and the last of which (paper 5) is in the status of manuscript before submitting. In the first two papers the role of common carp catches is focused. By using multivariate techniques it is studied if the increased exploitation of carp increases also the exploitation of other fish species. Time series of carp catches serve as an explanatory variable, other species catches through the same time are processed as independent variables. According to expectations the positive effect of carp catches on those of the other species was approved at the river section with the highest expected density...
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The influence of environmental factors on amphibian assemblages
Kára, Martin ; Pivnička, Karel (advisor) ; Frouz, Jan (referee)
Like a large part of western Europe also from the Czech landscape is dramatically disappearing amphibians. This negative trend occurred due to several factors, some of which is undoubtedly the most significant loss of suitable breeding areas. During the years 2009 and 2010 I monitored a total of 31 tanks in a part of the former districts of Liberec, Jablonec nad Nisou and Semily, in which were multiplied frog (Rana temporaria) and toad (Bufo bufo). On these localities I've watched a few environment variables, which I assume that may affect the successful development of amphibians from egg stage to metamorphosis. The success of development, I determined by counting congeries in the spring and then finding the number of tadpoles in the tank survived the conversion. The results of multiple linear regression shows that the developmental stages of brown frog react negatively to the increasing altitude and increasing the number of eggs per unit area of the tank. On the contrary, they thrive better in larger, at least partially shaded tanks, which are subject to fluctuations in water level. For toad are suitable not very deep, partially shaded tanks, with a stable water level, vegetation and aquatic vegetation free shores. Also managed to find the eggs and tadpoles of toads react negatively to the...
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Insects as human food
Augustinová, Šárka ; Pivnička, Karel (referee) ; Frouz, Jan (advisor)
Insects as a traditional source of food widespread in tropical and subtropical regions offer significant nutritional, economical and ecological gains not only to rural communities. Western bias against insects led to gradual reduction of usage of insects as food without any compensation for lost sources of nutrition and other benefits. Current efforts of the Western world to prevent starvation of population and undo the consequences of inconsiderate human interventions into the environment are often futile and ineffective. One of possible answers to these global problems could be reestablishment of insects as a food source for the native population. Insects offer a renewable source of protein with nutritional values as high as 3186kJ per 100g of solids which exceeds the values of most species traditionally cultivated. The protein content varies throughout the various insect species from 30% in wood-worms to 81% in wasps of the genus Polybia. Moreover, the quality of these proteins is very high and the high values of the amino acids contained outperform the FAO recommended designs. Many species contain important minerals such as calcium, sulfur, iron, phosphor, magnesium and zinc and are as well rich in B vitamins, niacin, riboflavin and thiamin, which are often not incorporated enough into standard meal...
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Management of the protected areas in sand habitats
Šímová, Kamila ; Pivnička, Karel (referee) ; Münzbergová, Zuzana (advisor)
Management of the protected areas in sand habitats is a thesis interested in the management techniques in relation to the sand habitats. In Central Europe, sand habitats are a rare and threatened grassland biotope. In the Czech Republic, we can find natural sand habitats localities, which are threatened by the human impact and anthropogenic localities, which tend to increase in number. Diversity and richness of the natural stands is gradually decreasing due to the high sensitivity of the species to any change of the local environment. These changes are mainly caused by the human activity. The negative effects are eutrophication, acidification and accelerated succession. The management of the sand habitats should contain many succession regulation tools and techniques reducing eutrophication. I discuss mowing, removal of the expansive plant species, pasturage, burning and sod disturbance or sod cutting. Each of these methods has specific impacts on the ecosystems and the best management combines them to achieve the best performance of the protected area. The most preferable method seems to be sod cutting, due to its high effectivity. However, there are many questions about sod cutting that need to be answered in a future study, such as how the population dynamics after sod cutting will look like, what the...
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