|
|
Effects of wild ungulates on vegetation in an abandoned landscape
Horčičková, Eva ; Herben, Tomáš (advisor) ; Diekmann, Martin (referee) ; Tichý, Lubomír (referee)
Wild ungulates are considered one of the major drivers for shaping terrestrial ecosystems, which has been developing since the early Cenozoic. Understanding the effects of ungfulates on vegetation is necessary for qualified knowledge how European landscape looked prior to human habitation and how it would look like without human intervention. Further, such understanding is of practical importance as management information necessary for managing abandoned landscapes. While the present-day wild ungulate European fauna does not contain several large grazers like auroch (Bos primigenius) anymore, the landscape has long been affected by them. It thus possesses historical experience of response to large grazers, which has been further maintained by livestock grazing. Importantly, the European landscape is experiencing a steady increase of populations of deer (Cervidae) and wild boar (Sus scrofa) with major effects of vegetation and landscape structure. While the effects of these present-day dominants have been studied mainly in forest habitats, there is a growing evidence that they both promote species diversity of forest understory and, interestingly, preferably feed in open vegetation and thus can affect broader landscape heterogeneity. The main aim of this thesis is therefore to examine effects of...
|
|
| |
|
|
Effects of wild ungulates on vegetation in an abandoned landscape
Horčičková, Eva ; Herben, Tomáš (advisor) ; Diekmann, Martin (referee) ; Tichý, Lubomír (referee)
Wild ungulates are considered one of the major drivers for shaping terrestrial ecosystems, which has been developing since the early Cenozoic. Understanding the effects of ungfulates on vegetation is necessary for qualified knowledge how European landscape looked prior to human habitation and how it would look like without human intervention. Further, such understanding is of practical importance as management information necessary for managing abandoned landscapes. While the present-day wild ungulate European fauna does not contain several large grazers like auroch (Bos primigenius) anymore, the landscape has long been affected by them. It thus possesses historical experience of response to large grazers, which has been further maintained by livestock grazing. Importantly, the European landscape is experiencing a steady increase of populations of deer (Cervidae) and wild boar (Sus scrofa) with major effects of vegetation and landscape structure. While the effects of these present-day dominants have been studied mainly in forest habitats, there is a growing evidence that they both promote species diversity of forest understory and, interestingly, preferably feed in open vegetation and thus can affect broader landscape heterogeneity. The main aim of this thesis is therefore to examine effects of...
|
|
| |
|
|
Communitiy level impacts of alien invasive plants and the role of native range habitats in plant invasions
Hejda, Martin ; Pyšek, Petr (advisor) ; Duchoslav, Miloš (referee) ; Tichý, Lubomír (referee)
Conclusions Categorization of the species studied according to their impact on invaded communities This study focused on neophytes, species introduced after 1500 A.D., because their impact on native vegetation is higher and more obvious than that of archaeophytes, introduced before that date, due to considerable invasion dynamics and relatively short residence time (Pyšek et al. 2002). The target neophytes, included in the study, differ strongly in their community level impacts. Impatiens glandulifera had a miniscule impact on species diversity and composition, both in the removal experiment and comparative study (Chapter I). This small impact is likely to be associated with this annual species' lower competitive strength, which has a modest root system and forms stands that are not homogeneous in terms of cover. The density of I. glandulifera populations is known to decrease during the vegetation season, as plants fall due the weight of climbers, which are common in invaded riparian communities (Calystegia sepium, Cuscuta europaea - see Beerling & Perrins 1993). Moreover, the character of communities in which I. glandulifera invades, mostly riparian nitrophilous vegetation, does not provide opportunities for competitively weak species even if they are not invaded. This vegetation is dominated by tall,...
|
|
|
Dynamics of rare and threatened species on local and regional scale- from theory to practice
Lampei Bucharová, Anna ; Münzbergová, Zuzana (advisor) ; Tichý, Lubomír (referee) ; Jiménez, Ares (referee)
To assess the status of a rare plant species, we must first understand the factors that affect the size of populations and their numbers. In this thesis, I study processes affecting plant species prosperity on local scale (paper 1), factors influencing species distribution in landscape and ability of species to colonize new habitats (paper 2) and species traits responsible for gene flow between established populations (paper 3). Since I work with rare plants, I also aim to turn theoretical knowledge into practical recommendations for nature conservation (paper 4) to help effectively preserve rare and endangered species. In the first 3 papers, I work with two rare fern species restricted to serpentine rocks, Asplenium adulterinum and A. cuneifolium, in a study system covering 10 × 10 km. I found that both species are long living (several decades) and in the study region, populations are in a good state and slowly growing. Even very small populations (10 individuals) have quite high chance to survive. In both fern species, I found dispersal limitation, which might be surprising regarding huge production of small spores in ferns (paper 2). The species differ in ploidy and thus, also mating system. A. adulterinum is tetraploid and its main breeding system is intragametophytic selfing. A. cuneifolium is...
|
|
|
Imprints of history in post-agricultural forests
Vojta, Jaroslav ; Suchara, Ivan (advisor) ; Honnay, Olivier (referee) ; Tichý, Lubomír (referee)
IMPRINTS OF HISTORY IN POST-AGRICULTURAL FORESTS Ph.D. Thesis Jaroslav Vojta Charles University in Prague, Faculty of Science Praha, 2010 Promotor: Ivan Suchara List of original papers I. Relative importance of historical and natural factors influencing vegetation of secondary forests in abandoned villages (Jaroslav Vojta - Preslia 79: 223-244) II. Land use legacies in post-agricultural forests in the Doupovské Mountains, Czech Republic (Martin Kopecký & Jaroslav Vojta - Applied Vegetation Science 12: 251-260) III. Woody vegetation continuity, topography, and distance to ancient forests have complex effects on the vegetation and species richness of abandoned pastures (Lucie Drhovská & Jaroslav Vojta - submitted) 1 Introduction Land use changes have had a profound effect on vegetation cover. Often, succession results in the recovery of forests on former agricultural land. As areas of post-agricultural forests become increasingly prominent in landscapes of developed countries, these processes have attracted the attention of ecologists. Many questions have arisen regarding the possibility of restoring original forest communities on former agricultural lands (Flinn and Vellend, 2005; Hermy and Verheyen, 2007). At the same time, current and past land use changes could be seen as "natural experiments" that could...
|
|
| |
|
| |
|
| |
guest ::
RSS feed.