| Popis: |
1 Abstract Newly created habitats present a unique model environment for the study of succession and related processes. Their relative isolation and the possibility to observe community assembly dynamics from the very beginning makes these experiments repeatable under controlled conditions. Planktic organisms with short generation cycles represent useful model organisms for the research of succession and related features like the influence of environmental variables or priority effect. The thesis aims at describing the succession of phytoplankton in a set of 20 experimental ponds, where phytoplankton structure and environmental parameters have been observed for six years (2007 ̶ 2012). The ponds are located in Liběchovka River-bed, which is a part of Kokořínsko Protected Landscape Area. The target locality is protected by the Ramsar agreement as a habitat for pulling birds and amphibians. We used classical and multidimensional statistical methods (PCA, DCA, CCA) to analyse the variability in species composition and shifts in environmental variables. Metacomunity structure indices (α,ß,γ) showed a decrease of α diversity accompanied by an increase in ß diversity over the study period, which have been caused by a marked differentiation of communities in 2011 ̶ 2012. γ diversity peaked in the middle of the... |
