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Selected impacts of climate change on birds in European mountains: shifts in altitudinal distribution, population changes and changes in phenology
Mikulcová, Eliška ; Reif, Jiří (advisor) ; Hološková, Adriana (referee)
Many studies focused on the impact of the climate change on organisms including mountain birds. Mountain birds are particularly threatened by the impact of climatic change because they occur in an extreme environment. Climate change impacts mountain birds through increasing temperature, which affects their altitudinal shifts and abundances. These two variables depend also on species-specific traits, distribution area and habitat change. This thesis aims to sort knowledge about impacts of climate change on mountain birds and to explain the variability of altitudinal shifts of these species. Species occupying lower altitudes, open habitat species and short-lived species showed the biggest upward shifts. Downward shifts occurred when the impact of habitat change outweighed the impact of climate change. No significant shifts were recorded in species that respond to climate change by changes in phenology which likely compensate the adverse climate change impacts without the need of translocation. Population trends were usually negative with the steepest declines in high- alpine species, ecological specialists, long-distance migrants and short-lived species. In order to reduce decline in numbers, it is important to set up effective local vegetation management and globally stick to climate targets. Key...
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Floral biology of tropical alpine plants
Holzbachová, Lucie ; Sklenář, Petr (advisor) ; Ptáček, Jan (referee)
Tropical alpine environments are characterised by specific environmental conditions to which the local plants adapted through evolution. The specificity is especially in a strong diurnal climate with temperatures falling below zero at nights. At the same time, this environment lacks thermal seasonality, which allows growth and flowering throughout the year. While floral biology is relatively well described in temperate regions, it has only been studied sporadically in the tropics. This study summarises the knowledge of floral biology in tropical alpine environments with a focus on zoophily plants. The principal part of this work is dedicated to floral traits, focusing on flowering phenology, which is diversified for every species during the year. In this way, plants face competition, especially for their pollinators, which decrease in abundance with altitude. Although not all phenological strategies have been studied so far, we can find several main flowering schemes. This literature review points to unexplored research topics about floral biology of plant inhabiting tropical mountains that might provide a basis for future studies.
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Floral biology of montane plants and its change with elevation and phenology, effect of pollination stochasticity and other factors on the number of ovules
Nekola, Matyáš ; Sklenář, Petr (advisor) ; Koupilová, Klára (referee)
The number of ovules that each plant produces reflects its ability to adapt. There are several factors that affect ovule production. An important factor is elevation. With the rising elevation also rises the severeness of stochasticity and pollen limitation. Additionally, at the begining of the vegetational season the pollination should be more stochastic and limited. One of the strategies that plants use is called Bet-hedging strategy. Main part of this strategy is the overproduction of the ovules in the ovaries. This above average number of ovules will be used in the case that the flower receives higher than average pollen load. In the end, the plant can compensate for the occasions when the received pollen load is lower. Alpine environment is proposed to have higher pollination stochasticity and pollen limitation. Hence this work is built on the hypothesis that number of ovules will increase with elevation and will be higher at the beginning of the vegetational season in accordance with Bet-hedging strategy. In my diploma thesis I quantified ovule number in 9 species namely Arabidopsis halleri, Calluna vulgaris, Campanula rotundifolia, Melampyrum pratense, Melampyrum sylvaticum, Silene dioica, Silene vulgaris, Trientalis europaea, Vaccinium vitis-idaea, Veronica chamaedrys and Viola lutea subsp....
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Citizen science as a tool for monitoring phenological changes in our reptiles
ONDŘEJKOVÁ, Pavlína
The diploma thesis deals with the length of seasonal activity of reptiles in Czech republic and follows their phenological shift in response to temperature changes. The first part of the thesis is devoted to the factors influencing the reptiles' occurrence, phenology, and the importance of citizen science and its possible con-nection with data collection. The second part includes monitoring results regarding the length of activity of individual species over the years and their shift in the be-ginning and end of activity. All species show a lengthening of the season - to ear-lier dates of their first appearance in spring and enter hibernation later. The largest difference in the shift of the beginning and end of the activity was shown by the Eastern slowworm (Anguis colchica). The least significant extension of activity towards the beginning of the year was shown by the Grass snake (Natrix natrix) and towards the end of the year the European pond turtle (Emys orbicularis). Records of reptile sightings were obtained from the Nature Conservation Discovery Database.
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Hodnocení dřevin, rostoucích v rozdílných stanovištních podmínkách města Brna
Čadová, Barbora
The urban environment is very specific for growing of trees. The tree species in the cities are often influenced by complex of negative stressors and a different microclimate versus the free landscape. This diploma thesis deals with evaluation, monitoring, measurement and comparison of trees on two localities in central part of Brno. There are compared sites of Denis Settlement and part of the park under Špilberk Castle. Tracking took place during growing season from March to October 2017. It was found that the phenological development was faster on the surface of Denis' set for about 4 days. During the inventory was discovered sponge Hericium erinaceus on the species Koelreuteria paniculata from the Spilberk area. The translucency of light intensity by the crown decreased until August. The amount of chlorophyll in the leaves increased to July and in some cases until August.
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Floral biology of montane plants and its change with elevation and phenology, effect of pollination stochasticity and other factors on the number of ovules
Nekola, Matyáš ; Sklenář, Petr (advisor) ; Koupilová, Klára (referee)
Pollination is a highly stochastic process. When also combined with pollen limitation, it could have notable effect on the number of seeds and therefore the plant fitness. Plants in order to compensate for the high pollination stochasticity use Bet-hedging strategy (Burd et al., 2009). Main part of this strategy is the overproduction of the ovules in the ovaries. This above average number of ovules will be used in the case that the flower receives higher than average pollen load. In the end, the plant can compensate for the occasions when the received pollen load is lower. Alpine environment is proposed to have higher pollination stochasticity and pollen limitation. With the rising elevation also rises the severeness of stochasticity and pollen limitation. Additionally, at the beginning of the vegetational season the pollination should be more stochastic and limited. Hence this work is built on the hypothesis that that number of ovules will increase with elevation and will be higher at the beginning of the vegetational season in accordance with Bet-hedging strategy. The increase of the ovule numbers with the rising elevation wasn't confirmed. On the other hand, there were documented connections between declining number of ovules throughout the season and 1) distribution of ovules among...
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Phenology of selected species of waders (Charadriiformes: Scolopacidae: Calidrinae) passage across the Czech Republic, analysis based on faunistical records.
JANŮ, Kateřina
Bird migration is controlled by several different factors which primarily influ-ence its timing (phenology). The phenology of this phenomenon varies depending not only on species, but also gender or age of individuals. At present, there is a considerable potential for its research in using faunistic observations from databases open to the public. This data is suitable for research of various phenological phe-nomena due to the long-term data collection as well as the quantity of the output. The aim of this thesis was to evaluate the timing of migration of selected spe-cies of birds of the Arenaria and Calidris genera across the territory of the Czech Republic, to compare it with other similar studies and to evaluate the possibilities of using faunistic databases available in the Czech Republic for this type of study. During the spring migration, the species with the earliest passage across the Czech Republic is Calidris pugnax (the passage peaks between 11th and 20th April), whereas the species with the latest peak of the spring migration is C. falcinellus (around 20th May). The species with the earliest determined peak of a passage dur-ing the autumn migration was C. teminckii (between 11th and 20th August), the spe-cies passing through Czech territory the latest being C. alba (between 11th and 20th September). Among the most frequently migrating species are C. alpina and C. pugnax, whereas the species with the lowest number of passing individuals (apart from rare species) are C. canutus and C. falcinellus. The results recorded about the timing of migration by individual species point to similarities with other studies of this phenomenon, however differences were found, regarding some of the species. In recent years, there has been a noticeable increase in the number of faunistic records, which means further possibilities for their evaluation in the future. This thesis could, among other things, serve as a basis for a better understanding of the phenological patterns of migration of not only these bird species. Observing pheno-logical phenomena helps us understand both the relationships between individual organisms as well as the relationships between organisms and the environment and their mutual influence.
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Diversity of floral functional traits and its seasonal changes in alpine environment
Plachtová, Kateřina ; Sklenář, Petr (advisor) ; Janeček, Štěpán (referee)
Floral functional traits characterize flowers and mediate contact between entomogamous flowers and their pollinators. Their form depends on many biotic and abiotic factors. The floral functional traits tend to be similar in high altitudes. However, the overall diversity of the floral functional traits does not vary significantly between altitudes. On the other hand, how temporal diversity of the floral functional traits varies during the flowering season was not studied yet. And this is the focus of this thesis. The aim of this study is to examine the hypothesis, whether the diversity of the floral functional traits changes in plant communities of alpine and montane meadows during the flowering season and also between them. The alpine and montane meadows are located in the area of Luční hora in the Krkonoše National Park. Morphological and spectral characteristics of the flowers were measured on both meadows. Abundance of flowering species and their flowers were measured every three weeks during five periods of the season. Diversity of the floral functional traits was obtained, for both meadows and all the measured periods of season, by weighting the floral functional traits with the species abundances. Using multivariate analysis, differences of temporal and altitudinal diversity were studied....
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Microclimatic conditions as determinant of Vaccinium myrtillus pollination
Veljačiková, Hana ; Janovský, Zdeněk (advisor) ; Červenková, Zita (referee)
Climate change affects phenology and distribution of plants and animals and causes a mismatch in plant-pollinator interactions. These changes are clearly manifested in extreme environments such as mountains or the beginning of the growing season. Vaccinium myrtillus is an important temperate and boreal species, inhabiting and often dominating such environments where changes due to global warming are already appearing. Flowers start to appear in April and May at the very beginning of the growing season. Without pollination, flower will almost never form a fruit. When comparing fruit set, it is possible to observe whether the flower has been pollinated and thus the quality of pollination in given conditions. Using experiments on the mountain heath in the Brdy Protected Land Area, I found out how the quality of pollination differs in different microclimatic conditions. I compared fruit set of chosen flowers and seed set in their fruits. Flowers blooming at the end of the flowering season had the greatest success in fruit formation, when I recorded a greater number of pollinators in the experimental environment. V. myrtillus bloomed more intensively at the beginning of the flowering season. Even so, fewer fruits were produced from flowers at that time. Bumblebees abundance was correlated to fruit and...
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