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The efect of uncut grass strips on the functional diversity of selected meadow insects communities
Kapr, Jan ; Šípek, Petr (advisor) ; Harabiš, Filip (referee)
This thesis compares the species diversity and the functional diversity of three ecologically important insect taxa (Orthoptera, Heteroptera and Hymenoptera:Aculeata) between production meadows, where the uncut grass strips are left and the meadows mown in the conventional way. Leaving the uncut strips of vegetation is an example of the agri-environmental schemes which were introduced to try to mitigate the negative impact of intensive agriculture on the biodiversity of the production grassland. Here I present part of the results of a four-year study focused on the response of insect abundance and diversity to the meadow management. Based on the recorded insect species diversity, the ecological traits of the insect species were analysed. The functional diversity analysis helps to better understand the ecological relationships in production meadow communities and to evaluate the importance of this agri-environmental scheme for various insect taxonomical and functional groups. Key words: uncut grass strips, agro-envi schemes, functional diversity, production meadows, insect decline
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Factors affecting dragonfly species composition in newly created pools and assessment of invertebrate predation on pools zooplankton
Dobiáš, Jakub ; Černý, Martin (advisor) ; Harabiš, Filip (referee)
To identify and quantify the influence of physico-chemical, biotic and geographic factors on the population of dragonflies (Odonata) is an essential tool for research of their ecology. The aim of this study was to 1) assess how these factors influence species richness, diversity and spatial distribution of dragonflies in 42 newly constructed or renewed pools located in the Kokořínsko Protected Landscape Area, which is characterized by two valleys of Liběchovka and Pšovka creeks, low human impact, and a great diversity of small water bodies and 2) use laboratory experiments in order to estimate the relationship between large predatory invertebrates of these pools (Aeshna cyanea, Coenagrion puella, Chaoborus crystallinus and Notonecta glauca) and their common prey (Daphnia curvirostris) in an artificial environment with or without aquatic macrophytes. The pools were monitored and sampled between years 2005 and 2006. In total, 23 dragonflies species were found inhabiting these lentic habitats, comprising 11 species belonging to the suborder Zygoptera and 12 species belonging to the suborder Anisoptera, including a rare species Sympetrum depressiusculum (larvae). Most variability in the dragonfly species richness was explained by the size of the water surface area, followed by the location of the pools (inside...
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Odonata in the urban landscape
Fiala, Bohumil ; Černý, Martin (advisor) ; Harabiš, Filip (referee)
Urbanization is currently one of the main causes of landscape destruction, endangerment of species and homogenization of natural communities. Dragonflies are an important part of freshwater ecosystems. Due to their amphibious life cycle, they are influenced by environmental factors both in a water and on a dry land. Despite the negative impact of urbanization on the environment, the urban landscape has the potential to host a great diversity of organisms, including dragonflies and damselflies. The best way to support local diversity of Odonata is by appropriate management of freshwater habitats, including promoting diversity of aquatic, litoral and riparian vegetation, preserving the original bottom and banks of both lotic and lentic waters and improving water quality in cities. The connectivity of individual localities in the landscape and the reduction of ecological traps are also important ways to ensure the stability of urban populations. Small artificial water reservoirs and well-preserved secondary habitats have the highest conservation potential in most cities. Dragonflies can also play the role of umbrella species for the protection of freshwater communities (not only) in urban areas.
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Individual fitness in Odonata: effect of phenotypic traits
Rohlíková, Barbora ; Černý, Martin (advisor) ; Harabiš, Filip (referee)
My study summarizes current knowledge of the aspects influencing reproductive success of dragonflies (Odonata). As with other organisms, the reproductive success (fitness) differs on the individual level, and it is influenced mainly by factors related to body structures. The body characteristics of individuals dragonflies affect their totally physical performance. The most studied factors include size, pigmentation and fat reserves; the individual performance is influenced also by the weight, fluctuating asymmetry, age etc. Some of these factors apply during larval development. However, the precopulatory phase (epigamic behaviour) is the most explored, since during that, males gain control and defend territory or perform courtship behaviour. At this phase, beside physical capabilities, there are other important factors such as ornamentation (pigmentation) or fluctuating asymmetry; some damselflies have developed various strategies which, at some species (namely within Calopterygidae), may evolve into colourful dimorphism of males. Next, the copulation in dragonflies is very specific, besides usual sperm transfer it often involves removal of sperm of predecessors to ensure paternity. At many species, the copulation is followed by the postcopulatory phase, during which the males secure their...
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Factors affecting dragonfly species composition in newly created pools and assessment of invertebrate predation on pools zooplankton
Dobiáš, Jakub ; Černý, Martin (advisor) ; Harabiš, Filip (referee)
To identify and quantify the influence of physico-chemical, biotic and geographic factors on the population of dragonflies (Odonata) is an essential tool for research of their ecology. The aim of this study was to 1) assess how these factors influence species richness, diversity and spatial distribution of dragonflies in 42 newly constructed or renewed pools located in the Kokořínsko Protected Landscape Area, which is characterized by two valleys of Liběchovka and Pšovka creeks, low human impact, and a great diversity of small water bodies and 2) use laboratory experiments in order to estimate the relationship between large predatory invertebrates of these pools (Aeshna cyanea, Coenagrion puella, Chaoborus crystallinus and Notonecta glauca) and their common prey (Daphnia curvirostris) in an artificial environment with or without aquatic macrophytes. The pools were monitored and sampled between years 2005 and 2006. In total, 23 dragonflies species were found inhabiting these lentic habitats, comprising 11 species belonging to the suborder Zygoptera and 12 species belonging to the suborder Anisoptera, including a rare species Sympetrum depressiusculum (larvae). Most variability in the dragonfly species richness was explained by the size of the water surface area, followed by the location of the pools (inside...
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Temporal variability in spatial distribution of carabid beetles in agricultural landscapes
Seidl, Miroslav ; Knapp, Michal (advisor) ; Harabiš, Filip (referee)
The aim of this thesis is to work out a brief literary research focused on spatial distribution of carabid beetles (Coleoptera, Carabidae) around arable field-woodland boundaries throughout the season. Substantial part of this thesis consistsof thefield experiment aiming to explore given issue in the model area near Sedlčany. Carabid beetles were collected employing pitfall traps along four transects perpendicular to arable field-woodlot boundaries. Beetles were sampled during five sampling periods, but only four complete (undamaged) temporal samples series were used for final statistical analyses:1) early spring, 2) late spring, 3) summer and 4) late autumn.Three species groups were identified according to their habitat specialization:1) open habitat specialists, 2) habitat generalists and 3) forest specialists; and these groups were analysed seperately.
Total species diversity was highest in area of ecotone between arable field and woodlot.The edge between habitats was preferred by habitat generalist species and open habitat specialist species also spilled over here. Distribution of relative species richness and relative activity density was not stable in time. Spatial distribution of forest species was relatively less variable. Open habitat species aggregated within habitat boundaries instead of field interiors in early spring, probably as a result of overwinteringbehaviour. Generalists were also aggregated in the edge between habitats in autumn period and during early spring occurred relatively more in the centre of woodlot than in other periods. Species composition of carabid beetles assemblages depended partly on season and also on position of transect. There was also a significant interaction between spatial and temporal variability in species composition of carabid assemblages. Woodlot assemblages seem to be less variable in time.
The results of this thesis contribute to extension of knowledges on distribution of carabid beetles in agroecosystems, where many carabids act aspredators of various pests. The biggest changes in spatiotemporal distribution of carabid beetles in agricultural landscape could be linked with preference of adults to overwinter out of arable land.
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The effect of ecotones on the overwintering of Winter damselflies (Odonata: Lestidae)
Dolejšová, Lucie ; Harabiš, Filip (advisor) ; Michal, Michal (referee)
Sympecma fusca is a species of winter damselflies with unique life history. The uniqueness of life history is coupled with overwintering in adult life stage in terrestrial environment, which is associated with high mortality rate. Such risk can be reduced by preference for specific habitats. Since terrestrial environment is frequently affected by anthropogenic disturbances, winter damselflies must respond to interventions into their habitat. This thesis focuses mainly on anthropogenic interventions into the habitat of winter damselflies and the impact of such disturbances on the distribution of individuals of species Sympecma fusca. Capture-Mark-Recapture Method was chosen for modelling of population dynamics in selected transects. Data collection took place during the pre-reproductive period within two years. Year-on-year comparison showed a decrease in abundance as well as changes in distribution of individuals in the studied transects. Individuals responded to habitat disturbances by searching for alternative micro-habitats, preferring places unaffected by anthropogenic disturbances. The acquired data indicate that winter damselflies are able to respond actively to environmental changes, nevertheless number of suitable habitats decreased significantly in the given site. This thesis is only a pilot study. Therefore, other reference sites are suggested for further study of anthropogenic influence on the life history of winter damselflies.
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Population and spatial dynamics of Winter Damselflies (Odonata: Lestidae)
Jablonická, Zuzana ; Harabiš, Filip (advisor) ; Kadlec, Tomáš (referee)
The main subject of this study was Sympecma fusca, damselfly species representing life history with many specific adaptations. One of the unique adaptation is overwintering in adult life stage outside the water habitat. The aim of this thesis is to analyze distribution of this species in terrestrial environment, as well as changes in abundance during the season. Sympecma fusca is common winter damselfly in Czech Republic, occurring on variety of still freshwater habitats with rich vegetation. During overwintering this species actively searching for micro-habitats situated in terrestrial environment, providing shelter and reducing the mortality risks. Capture-Mark-Recapture Method was applied to describe the population dynamics of this species. The experimental part was divided into two periods: pre-reproductive (autumn) and reproductive (spring). Subsequent analysis provide estimation of total number of individuals in population during season. The results showed significant habitat preference of ecotones between forest and meadow over forest and open habitats. However, this preference was confirmed only during pre-reproductive period, the time when imagoes were looking for suitable shelter for the overwintering. These findings can be used to in understand the habitat preference of this species, but also general factors that can affect its abundance.
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Is there any seasonal differences in terrestrial habitat use in dragonflies?
Hronková, Jana ; Harabiš, Filip (advisor) ; Aleš, Aleš (referee)
Dragonflies (Odonata) passing through several life stages during their life cycle. During metamorphosis between stages, they did not change only morphology, but also habitat preferences. Although they are associated to aquatic environment during larval stage, adults are much more mobile and can utilize the surrounding terrestrial habitats. Adult dragonflies are also involved in to terrestrial food chains. However the relationship, between the quality of terrestrial habitats and the diversity of dragonflies as well as seasonal changes in utilization of these habitats are still not known. This thesis aiming to analyze the influence of seasonality and distance from aquatic habitat on the abundance of dragonflies. Moreover, the differences in fish farming intensity were considered in the analyses. Fieldwork took place during 2015 from May to September. Data from 29 localities of Czech Republic were included. It is not surprising that I found significant influence of seasonality, on the abundance of all species, as well as a negative relationship between dragonfly abundance and distance from water reservoir. Interestingly, it was found, that dragonfly utilization of terrestrial areas around the extensively managed habitats was significantly higher than in habitats around intensively managed ponds. These findings demonstrate the importance of terrestrial habitats for dragonflies, especially those occurring around extensively managed water habitats.
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