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Succession of mollusk assemblages in quarries of Bohemian Karst
Kocurková, Alena ; Juřičková, Lucie (advisor) ; Horsáková, Veronika (referee)
Molluscan succession was studied in 18 abandoned limestone quarries of different age in Bohemian Karst. The number of species in studied quarries increases in the time. The less species were found in the oldest quarries. This trend was probably caused by habitat diversity decline although it is not conclusive. The best predictors of mollusk species composition are type of surrounding vegetation, light and the cover of tree layer. It is important to take into account correlations of the other environmental variables with light and the cover of tree layer. Compositions of mollusk assemblages of north and south-facing slopes differ, but these differences diminish with ongoing succession. Quarries represent suitable model sites for the study of succession.
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Influence of environment on morphological and stuctural characteristics of European snails
Holubová, Anna ; Juřičková, Lucie (advisor) ; Horsáková, Veronika (referee)
In this thesis, I explored the relationships among morphological characteristics of European land snail's' shells, their environment and life strategies. I assembled a database of morphological traits, characteristics of the environment and life strategies of land snails from literary sources. This file was merged with unique dataset from field sampling along a latitudinal gradient through Europe and the morphological characteristics of each species were averaged on real populations from particular sites. This package was analyzed by multivariate linear regression (GLM). In this work I demonstrate that the color pattern is affected by latitude and occurs mainly in gastropods with wider shell. Wide shell also appears mainly in snails with a smooth shell surface and shallower suture. Snails at lower altitudes mostly have calcified shell lips. A snail species with teeth in the mouth of shell, with ribs on the shell surface, and larger relative height of the shell, live in areas with higher calcium content in the leaf litter. Deep sutures on the shell are more frequent in shells from sites with higher rainfall seasonality. Especially in areas with higher rainfall seasonality we can find less gastropods with periostracal structures on the shell, however, their occurrence increase in areas with canopy...
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Influence of environment on morphological and stuctural characteristics of European snails
Holubová, Anna ; Juřičková, Lucie (advisor) ; Horsáková, Veronika (referee)
In this thesis, I explored the relationships among morphological characteristics of European land snail's' shells, their environment and life strategies. I assembled a database of morphological traits, characteristics of the environment and life strategies of land snails from literary sources. This file was merged with unique dataset from field sampling along a latitudinal gradient through Europe and the morphological characteristics of each species were averaged on real populations from particular sites. This package was analyzed by multivariate linear regression (GLM). In this work I demonstrate that the color pattern is affected by latitude and occurs mainly in gastropods with wider shell. Wide shell also appears mainly in snails with a smooth shell surface and shallower suture. Snails at lower altitudes mostly have calcified shell lips. A snail species with teeth in the mouth of shell, with ribs on the shell surface, and larger relative height of the shell, live in areas with higher calcium content in the leaf litter. Deep sutures on the shell are more frequent in shells from sites with higher rainfall seasonality. Especially in areas with higher rainfall seasonality we can find less gastropods with periostracal structures on the shell, however, their occurrence increase in areas with canopy...
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Succession of mollusk assemblages in quarries of Bohemian Karst
Kocurková, Alena ; Juřičková, Lucie (advisor) ; Horsáková, Veronika (referee)
Molluscan succession was studied in 18 abandoned limestone quarries of different age in Bohemian Karst. The number of species in studied quarries increases in the time. The less species were found in the oldest quarries. This trend was probably caused by habitat diversity decline although it is not conclusive. The best predictors of mollusk species composition are type of surrounding vegetation, light and the cover of tree layer. It is important to take into account correlations of the other environmental variables with light and the cover of tree layer. Compositions of mollusk assemblages of north and south-facing slopes differ, but these differences diminish with ongoing succession. Quarries represent suitable model sites for the study of succession.
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