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Bird abundances and the height of vegetation
Černohorská, Eliška ; Hořák, David (advisor) ; Hanzelka, Jan (referee)
Bird abundance, it means the number of individuals at a specific site relates to the number of species in the area. It is common that species-richer habitats contain more individuals. Bird abundance which detected most frequently during the breeding period is influenced by the vertical structure of the vegetation so that habitats with low vegetation (e.g. grasslands) occupy smaller numbers of birds than the cover of higher vegetation (e.g. shrublands and forests). Most often total bird abundance positively correlates with increasing vegetation height determined by successional stages. Based at the stated studies, it is evident that bird species respond to vegetation height and its changes in a specific way, therefore it is difficult to make general conclusions. Negative correlation between vegetation height and bird abundance observed in some studies can be caused by various methods of data collection on vegetation height in different areas. In my opinion, bird abundance relates more to vegetation density and vegetation stratification than to vegetation height. The reason is that bird occurrence in forest habitats is impacted by well-developed undergrowth not just by forest canopy height. To further clarify how vegetation height affects bird abundance, we need more research that would compare bird...
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The influence of foregoing crop on oats yield and quality
POLÁČKOVÁ, Jitka
Nowadays trend in Europe is returning to harvesting of traditional feeding crops. One of these crops is oat which has been universally used since time immemorial. Even today oats are processing and using in food industry and as a feed for farm animals. Further using of oats is in cosmetics and pharmaceutical industry. Oats contain high amount of proteins and fats, beta-glukan and mineral elements. Oats include vitamins B and E, lecitin, niacin and antioxidants. Research was executing on fields of University of South Bohemia in České Budějovice during one year. An impact on crop yield and quality of oats was observed in dissertation. There were used three crops corn, rape and cereal (spring wheat) in research. After these crops were sown ten varieties of oats, four naked and six husked varieties. At these varieties were observed an impact on crop yield and quality of oats. Evaluated characters were monitored during the vegetation, pre-harvest and post-harvest. There were observed germination and methane, height of vegetation, the degree of lodging oats, the number of lat m2, weeds, diseases and pests, after harvest was determine harvested grain yield, moisture and density, number of grains per panicle, thousand grain weight and grain on a network share during the vegetation. From the measured values follows that the best crop in year 2012 was corn and the best results were achieved by variety Abel, Avenuda, Atego, Pogon, Salo.
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