National Repository of Grey Literature 3 records found  Search took 0.01 seconds. 
Mycorrhizal fungal diversity along altitudinal gradients
Schultzová, Pavlína ; Kohout, Petr (advisor) ; Mašínová, Tereza (referee)
Mycorrhizal symbiosis is an integral component of all terrestrial ecosystems and the most widespread mutualistic association in the world. Nevertheless, our current knowledge regarding diversity patterns of mycorrhizal fungi along altitudinal gradients is considerably limited. Published studies to date suggest either a decrease in mycorrhizal fungal diversity with increasing elevation or a hump-shaped pattern, similar to the general altitudinal diversity patterns that have been observed in macroorganisms. Lower mycorrhizal fungal diversity at higher elevations in some regions may significantly impact host plants migrating upward due to global warming. Therefore, insights into the shifts in mycorrhizal fungal distribution along elevational gradients can provide better predictions of future effects of climate change on mycorrhizal fungi and host plants. In order to advance our knowledge of mycorrhizal fungal diversity, it is crucial to deepen our understanding of the factors that shape mycorrhizal fungal responses along altitudinal gradients.
Convergence of morphological, biochemical, and physiological traits of upper and lower canopy of European beech leaves and Norway spruce needles within altitudinal gradients
Rajsnerová, Petra ; Klem, Karel ; Večeřová, Kristýna ; Veselá, Barbora ; Surá, Kateřina ; Rajsner, Lukáš ; Holub, Petr ; Urban, Otmar
Climatic variation along altitudinal gradients provides an excellent natural experimental set-up for investigating the possible impacts of climate change on terrestrial organisms and ecosystems. The present work has explored for the first time the acclimation of upper versus lower canopy leaves or needles in European beech (Fagus sylvatica) and Norway spruce (Picea abies) forests along an altitudinal gradient. We tested the hypothesis that restrictive climatic conditions associated with high altitudes reduce within-canopy variations of leaf traits. The investigated beech and spruce forests were located on the southern slope of the Hrubý Jeseník Mountains (Czech Republic). All measurements were taken on leaves from the upper and lower parts of the canopy of mature trees (>60 years old) growing at low (400 m a.s.l.), middle (720 m a.s.l.), and high (1,100 m a.s.l.) altitudes. Generally, we observed that with increasing altitude, which is associated with adverse microclimatic conditions, a convergence of CO2 assimilation rate and other physiological, morphological, and biochemical characteristics between the upper and lower canopy occurred. However, differences in altitudinal response among individual traits and species were found. Such plasticity in acclimation of leaves and needles has the potential to cause substantial change in the photosynthesis of individual parts of forest canopies within the vertical profile and their contribution to the overall carbon balance of vegetation.
Trophic relationships between insectivorous birds and insect in Papua New Guinea
TVARDÍKOVÁ, Kateřina
The thesis describes diversity of birds along a complete altitudinal gradient and in forest fragments in lowlands of Papua New Guinea. It focuses separately on the diversity of different feeding guilds, and discusses their links to habitat and food resources. More specifically, it focuses on forest insectivorous birds, their predation pressure on arthropods, feeding specializations and preferences, and some of the ways how insectivores search for food.

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