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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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The influence of the water quality on managed ichthyocenosis in the Berounka River, 1975-2003
Pivnička, K. ; Humpl, Martin
In 1962-2004 the stepwise increase of the concentration of NO3-, NH4+, Cl-, and SO42- was found up to the end of 1980´s with their subsequent decrease; only for BOD the gradual decrease in all sites and years was observed. These environmental factors (EF) together with the fishery statistics from two fishing wards (B7 and B8) in the Berounka River near Radnice were used in RDA models for the evaluation of the variability in fish assemblage structure in relation to the given EF. The best results in both wards were obtained using model with three EF (BOD, NO3-, SO42-), next models with four (five) factors explained more variability, some EF were, however, not significant. The partial effect of carp as EF on the yield of other species was non significant in B7 and closely above the significance (p=0.036) in B8. The changes in the frequency of fish species in fishery statistics are influenced by EF; the fishery statistics can be used for the evaluation of changes in fish assemblages in the past.
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Abundance of the barbel, Barbus barbus in the river Jihlava
Peňáz, Milan ; Pivnička, K. ; Prokeš, Miroslav ; Baruš, Vlastimil
A four-year experiment with a total of 993 individually tagged barbel, Barbus barbus, resulted in the assessment of survival and abundance. The Jolly-Seber method was used to estimate abundance from autumn 1999 to spring 2001 (minimum 233, maximum 563 ind./ha). The mean annual survival rate was 0.862, but the partial values assessed separately for seasons (spring - autumn and autumn - spring) differed considerably and the possible reasons for this phenomenon are discussed. On the basis of known survival rate, the abundance was subsequently estimated (for the entire studied stretch and per hectare) using the Petersen capture-recapture method for the period spring 1999 to autumn 2001. Its mean values reached 303 +- 110 ind./ha (minimum 195, maximum 498 ind./ha). These results were in autumn 2001 supported by another simultaneously conducted census following the removal method by Zippin (316 ind./ha).
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