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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Biodiverzita drobných zemních savců na loukách s odlišným typem managementu a vodního režimu na Třeboňsku. / Biodiversity of small terrestrial mammals on meadows with different management and water regime in Třeboňsko area

KOMENDOVÁ, Barbora January 2012 (has links)
The thesis builds on previous work comparing biodiversity of small terrestrial mammals at four localities with different management. The thesis significantly extends the previous work. The theoretical part consists of a literature search on the issue of the occurrence of small mammals in an area around the town Třeboň, their microhabitat preferences and the impact of farming on biodiversity of their communities. The practical part describes the species composition of small terrestrial mammals? communities and changes of their abundance and biomass during the three growing seasons, depending on the climatic characteristics of the locality. It includes evaluation of the results of the regular catches in traps (CMR method), which were realized from June to September between 2009 and 2011 (three catches once a year) at four sites with different management: Mokré louky - non mowed, Mokré louky - mowed, Cirkvičný meadow and a pasture (meadow) Jeţek. A total there were 553 individuals of small terrestrial mammals caught and we noted nine species: Microtus arvalis, Microtus. agrestis, Micromys minutus, Apodemus sylvaticus, Sorex araneus, Sorex minutus, Neomys anomalus, Neomys fodiens, Crocidura suaveolens and Apodemus sylvaticus. Various characters of biotopes provide differently suitable conditions for the establishment of populations according to their habitat requirements. The predominant species in Mokré louky mowed and non-mowed was Microtus agrestis and in the Cirkvičný meadow and Jeţek it was Microtus arvalis. The highest abundance and diversity were recorded in Mokré louky mowed and non-mowed. The highest biomass was recorded in 2009 and 2010 in summer, when temperatures were highest. In 2011, there was the highest biomass in the spring, probably because the previous winter was very warm. The highest Simpson's index of species diversity was in Mokré louky mowed in 2010. The relative abundance was highest of Microtus agrestis, Apodemus sylvaticus and Sorex araneus, alternately in Mokré louky mowed and non-mowed. Microtus arvalis had the highest abundance for all three years in the Cirkvičný meadow. The probability of capture during capture was always increasing, reaching 100%, as in the Microtus arvalis, Microtus agrestis, as well Apodemus sylvaticus. The highest probability of re-capture was at Apodemus sylvaticus, where 33% of the second day and 43% of the third day. The results presented in the thesis contributed to the project NPV 2B06023 MŠMT.
2

Life-history patterns of terrestrial mammals in the southern African subregion

Smit, Anne-Marie 07 April 2011 (has links)
Life-history features of terrestrial mammals in the southern African subregion were explored in an attempt to identify the factor(s) that may influence the evolution of common mammalian life-history patterns within this subregion. Allometry and phylogeny were found to underly most of the variation observed in life-history features. Residual variation was considered and age at maturity, gestation period and litter size emerged as additional features influencing life-history patterns. Southern African mammals could generally be arranged along a theoretical r-K continuum with small mammals having relatively short developmental periods and relatively large litter sizes represented at one extreme and large mammals having relatively long developmental periods with relatively small litter sizes at the opposite extreme. However, the carnivores did not conform to this expected general gradient suggesting that they may be an exceptional order as far as their life-histories are concerned. / Dissertation (MSc)--University of Pretoria, 2011. / Zoology and Entomology / unrestricted
3

The Impact of Human Presence on Terrestrial Mammals in Secondary Regenerating Forest of the Peruvian Amazon

Pandya, Duncan January 2023 (has links)
Human disturbance is becoming an ever-bigger threat to biodiversity across the globe and should continue to be a field of conservation priority. Urbanisation, research and tourism put unavoidable pressure on the surrounding flora and fauna, therefore we need to gain knowledge on how to reduce future harm. Here we investigated the effects of human presence on medium-large terrestrial mammals in the south-eastern Peruvian Amazon, using camera traps to measure the number of human and mammal observations at varying distances from our research centre and the hiking trails. Species richness and the Shannon and Inverse Simpson diversity indices were also calculated during the four-month study period. Nineteen species were detected across fourteen camera sites. Distance from camp was positively correlated with species richness and the diversity indices, but showed no correlation with total mammal observations. Distance from nearest trail was negatively correlated with species richness, total mammal observations and the diversity indices. Total human observations was negatively correlated with species richness and the diversity indices, but had no impact on total mammal observations. Nevertheless, these results often had high p-values and low sample size and therefore should be interpreted with caution. Omnivores were the most sensitive trophic guild, showing a statistically significant negative correlation with total human observations, and a statistically significant positive correlation with distance from nearest trail. It is important then to assess these responses to human disturbance at the community and species level, as to truly understand the impact we are having.
4

Mamíferos de maior porte em paisagens tropicais alteradas: seu papel em cascatas tróficas e fatores que determinam sua distribuição / Large mammals in altered tropical forest landscapes: their role in trophic cascade and factors that determine their distribution

Oliveira, Gustavo de 17 November 2011 (has links)
Nesta dissertação investigamos o papel dos mamíferos em cascatas tróficas nas florestas tropicais, e os efeitos da configuração espacial e qualidade do habitat assim como das atividades humanas atuais sobre a distribuição de mamíferos de maior porte em uma paisagem rural de Mata Atlântica. No primeiro capítulo, através de uma revisão da literatura sumarizamos e avaliamos a evidência empírica de que mamíferos estão envolvidos em cascatas tróficas em florestas tropicais com o objetivo de indicar os avanços, os problemas e os desafios nessa área. Poucos estudos empíricos e conceituais foram encontrados na literatura, todos realizados nas últimas três décadas, enquanto que a maioria dos estudos empíricos foi realizada nos Neotrópicos. Grande parte das hipóteses relacionadas a cascatas tróficas foi apenas proposta, e considera o homem como predador de topo. Além da maior parte das variáveis quantificadas não serem adequadas para demonstrar efeitos em cascata, a escala temporal da maioria dos estudos revisados foi curta para acessar estes efeitos sobre a comunidade de plantas que contém espécies longevas. Nenhuma hipótese abordou o efeito dos predadores de topo sobre as populações de presas pequenas via o controle da densidade e distribuição de mesopredadores. A maioria das hipóteses que encontramos na literatura se refere a outros efeitos indiretos causados por mamíferos, em particular através da dispersão de sementes e da disponibilização de nutrientes via fezes. Dessa maneira, demonstramos que o termo \"cascata trófica\" tem sido utilizado amplamente, englobando outros efeitos indiretos que se propagam via outras interações que não tróficas, e que a evidência empírica disponível até o momento de que mamíferos desencadeiam cascatas tróficas em florestas tropicais é pequena. No segundo capítulo, através da amostragem de 23 remanescentes florestais e do uso de modelos de ocupação e da abordagem de seleção de modelos, investigamos como fatores associados à configuração espacial e qualidade do habitat e a outras atividades humanas em andamento interagem e condicionam a distribuição de mamíferos terrestres de maior porte em paisagens intensamente modificadas pelo homem. A assembléia de mamíferos de maior porte encontrada na paisagem estudada é simplificada e dominada por mamíferos silvestres generalistas de médio porte, sugerindo que o controle de mesopredadores e a regeneração das florestas podem estar comprometidos. Os resultados também sugerem que: (1) a distribuição de mamíferos de maior porte deve ser condicionada mais por fatores associados à configuração espacial do que à qualidade do habitat florestal; (2) as atividades humanas atuais são tão ou mais importantes que a configuração espacial e a qualidade do habitat para a maioria das espécies. O tamanho dos fragmentos e a distância a rodovias, entre os fatores associados à configuração espacial, e a caça e a presença do cachorro doméstico, entre as atividades humanas atuais, foram particularmente importantes para a distribuição das espécies de mamíferos de maior porte. A relevância das atividades humanas em andamento sugere que estratégias de manejo que foquem em mudanças na atitude da população humana, através de programas de conscientização e educação, podem ter resultados significativos em termos da persistência de populações de mamíferos em paisagens rurais. / In this dissertation we investigated the role of large mammals in trophic cascades in tropical forests, and the effects of habitat configuration and quality as well as of current human activities on the distribution of large mammals in a rural Atlantic forest landscape. In the first chapter, through a literature review we summarized and evaluated the empirical evidence that mammals are involved in trophic cascades in tropical forest, with the aim of highlighting the progress, problems and challenges in this area. Few conceptual and empirical studies were found in the literature, all of which were performed in the last three decades, while most of the empirical studies were developed in the Neotropics. Most of the hypotheses related to trophic cascades were only proposed and not tested, and considered humans as top predators. Not only most of the quantified variables were not appropriate to demonstrate cascading effects, but also the temporal scale of most studies was short to detect these effects on plant communities composed of long-lived species. We did not find hypotheses addressing the effect of top predators on the populations of small prey through the control of mesopredator density and distribution. Most hypotheses in the reviewed literature refer to other indirect effects played by mammals, especially through seed dispersal and nutrient allocation via feaces. Thus, we demonstrate that the term \"trophic cascade\" has been used widely, encompassing other indirect effects that propagate through other, non-throphic interactions, and that the empirical evidence available so far that mammals are drivers of trophic cascades in tropical forest is weak. In the second chapter, through the sampling of 23 forest fragments and using occupancy models and a model selection approach, we investigated how factors associated with habitat configuration and quality and with other current human activities interact to define the distribution of terrestrial large mammals in human-modified landscapes. The large mammal assemblage from the studied landscape is impoverished and dominated by medium-sized generalist species, suggesting that both the control of mesopredators and forest regeneration may be compromised. Our results also suggest that: (1) the distribution of large mammals is determined mainly by aspects of habitat configuration rather than by aspects of habitat quality, and (2) current human activities are equally or more important than habitat configuration and quality for most of the species. Fragment size and distance to roads, among the factors associated with habitat configuration, and hunting pressure and domestic dog presence, among those associated with current human activities, were particularly important to the distribution of large mammal species. The relevance of current human activities suggests that management strategies that focus on changing people attitudes, through programs of education, can have significant results in terms of the persistence of mammal populations in rural landscapes.
5

Liniové krajinné prvky a biodiverzita drobných zemních savců v zemědělské krajině / Linear landscape elements and biodiversity of small terrestrial mammals in agriculture landscape

MARŠÁLEK, Martin January 2016 (has links)
Annotation The thesis deals with an influence of linear landscape elements and landscape heterogeneity on a biodiversity and population dynamics of small terrestrial mammals (STM) in an agricultural landscape of South Bohemia. The theoretical part consists of literally review about landscape, historical analysis of landscape structures development in the area of interest and summarizes existing knowledge about the ecology of present STM species. The aim of the practical part is to compare small mammals' biodiversity in three biotopes using capture-release-recapture method. The thesis follows my bachelor thesis and uses the same methods as in 2013. Data obtained in 2013 and 2015 were evaluated and the results were compared. In both years three three-days long captures were performed, always with 30 traps in 5 meters distance in every biotope. The species, sex, weight, foot length and age of captured animals were determined. In 2013, 60 individuals of three species of small terrestrial mammals were captured (Apodemus sylvaticus, Myodes glareolus and Microtus arvalis). In 2015, 444 individuals of four species were captured (Apodemus sylvaticus, Myodes glareolus, Microtus arvalis and Apodemus flavicollis). The total numbers of STM significantly differ between 2013 and 2015 (Wilcoxon's pair test, Z = 2,66; p = 0,008). The biotopes differ significantly in animal abundance in both 2013 (Chi-Square 114,1; d. f. = 2; p < 0, 0001) and 2015 (Chi-Square 346,96; d. f. = 2; p < 0, 0001). The highest species diversity and abundance were always found in linear landscape element (alley).
6

Potravní preference drobných zemních savců a jejich vliv na biodiverzitu rostlinných společenstev mokrých orchidejových luk / Food preferences of small terrestrial mammals and their influence on biodiversity of plant communities in wet orchid meadows

CUDLÍN, Ondřej January 2008 (has links)
Food preference of small rodents to consume the roots of wild plants with the emphasize on their impact to bulbs of orchid Dactylorhiza majalis has been studied on three localities during years 2002 - 2007. There were selected ten couples of plants in each plots, one individual of couple plants was protected by tin triangle. Indicated plants have been measured in the beginning (high, length and wide of the leaves and flower number) and at the end of growing period (number of capsules). Small mammals were snaptrapped for three nights in the autumn. On each locality four rows of 25 snap traps were situated, two rows through orchid plots and two without orchids. In years 2004 {--} 2007 the food preference was ascertained on studied sites. Roots of Daucus carota (as a control in year 2004) and roots of Selinum carvifolia (as control in years 2005 - 2007) and roots of tested plant were put into one rectangle "bait" of size 15 x 6 centimeters from gauze. These 50 "baits" were placed among 100 traps on each locality, every other trap, during snaptrapped of small mammals. Browsing was classified by six number scale. During years 2005 - 2007 food preference of Microtus arvalis under laboratory conditions of Science Faculty of South Bohemia University was achieved with the roots of the same species as we used during food preference on plots. During years 2006 -2007 bulbs of Dactylorhiza majalis from laboratory condition and a few idividuals from endengered meadows by revitalization of pond were added. During yeas 2006 and 2007 the contain of stomach from Microtus arvalis and Microtus agrestis, catched during autumn, was studied. Bulb destruction by small rodents during years 2002 - 2007 was not confirmed. But Microtus arvalis preferred bulbs of Dactylorhiza majalis under laboratory conditions and roots of Selinium carvifolium and Lysimachia vulgaris boths in laboratory and wet meadows. Destruction of orchid bulbs and more preferred roots of wild plants by small rodents could occur probably only in outbreaks of their population cycle. I did not observe this on studied plots. In mount of stomach from Microtus arvalis only 3% underground supply organs of plants; rest of stomach contain was consisted of aboveground green part of plants. This result was expexted, because small rodents prefere during vegetation period green part of plants.
7

Vliv způsobu hospodaření na biodiverzitu modelových skupin obratlovců {--} drobní savci. / The influence of management on biodiversity of vertebrates model groups {--} small mammals.

KOUTNÍKOVÁ, Lenka January 2010 (has links)
This thesis creates a part of more extensive scientific study, which evaluates effects of different agricultural management on ecological functions and on landscapes´s water regime in source water areas of Bohemian Forest. A one of examined characteristic of catchment is biodiversity of plant and animal communities. The aim of my thesis is a comparsion of diversity of small terrestrial mammals in three catchments with similar nature conditions, but different management. Small terrestrial mammals is a group of vertebrates often used for study of enviromental state, because of their high reprodctive potential, good invasive ability and ability to indicate the changes in environmental quality. The master thesis is a follow-up to a previous bachelor thesis and extends it significantly. A teoretical part involves literary review of small mammals´s occurrence in Bohemian Forest, their micro-habitat preferences and the effect of management on the biodiversity of their communities. Practical part of the thesis contains evaluation of the results of capture-mark-release trapping, which took place from June to September of the years 2007 and 2009. In those two years 52 individuals were captured. From this amount, 7 individuals were captured twice. Captured small mammals were included into 5 species, whose occurrence in studied localities was expected. There were yellow-necked mouse (Apodemus flavicollis - 22 individuals), field vole (Microtus agrestis - 6 individuals), common vole (Mircotus arvalis - 10 individuals), bank vole (Clethrionomys glareolus {--} 2 individuals) and common shrew (Sorex araneus - 5 individuals). In the Bukový potok catchment 20 individuals were captured in 2007 and only 2 individuals in 2009. They belong to species: Apodemus flavicollis, Clethrionomys glareolus and Sorex araneus. In catchment of Mlýnský potok no individual was captured in 2007 and 10 individuals of only one species (Mircotus arvalis) were captured in 2009. In Horský potok catchment 5 individuals were captured in 2007 and 8 individuals in 2009. Three species were found: Apodemus flavicollis, Microtus agrestis, Clethrionomys glareolus a Sorex araneus. The largest positive change of abundance between 2007 and 2009 was found in the Mlýnský potok catchment. The largest fall of abundanace was in the catchment of Bukový potok. Only in catchment of Horský potok the relatively stable abundance was noticed. The thesis was supported by projects: MSM 6007665806, NAZV-QH82106 a NPV2-2B08006.
8

Biodiverzita a populační dynamika drobných zemních savců na několika typech rekultivací na Velké podkrušnohorské výsypce / Biodiversity and population dynamics of small terrestrial mammals on various types of restoration in the area of Velká podkrušnohorská spoil heap.

CHARVÁTOVÁ, Pavla January 2011 (has links)
The aim of my thesis was to describe the biodiversity and try to outline the population dynamics of small terrestrial mammals on the Great podkrušnohorská spoil heap. We captured small mammals six times during the 2009 and 2010 seasons. We used the standard capture-mark-release method (CMR) with live traps in quadrates at five sites with different restoration type- wetland, forestry (alderwood and pinewood), agricultural and controlled succession. The observed data were processed in Microsoft Office Excel and by canonical correspondence analysis (CCA) in Canoco for Windows. In 2009 a total of 67 individuals of five small mammals´species were captured: Apodemus flavicollis, Microtus arvalis, M. agrestis, Myodes glareolus and Sorex araneus. The highest biodiversity (3 species) was recorded in wetland restoration. The highest abundance (20 individuals) was recorded in alderwood forestry restoration. In 2010 258 individuals of 7 species were captured: Apodemus flavicollis, A. sylvaticus, Microtus arvalis, M. agrestis, Myodes glareolus, S. araneus and Micromys minutus. As in 2009 the highest abundance was recorded in alderwood forestry restoration(60 individuals) and the highest biodiversity (7 species) was recorded in wetland restoration.
9

Mamíferos de maior porte em paisagens tropicais alteradas: seu papel em cascatas tróficas e fatores que determinam sua distribuição / Large mammals in altered tropical forest landscapes: their role in trophic cascade and factors that determine their distribution

Gustavo de Oliveira 17 November 2011 (has links)
Nesta dissertação investigamos o papel dos mamíferos em cascatas tróficas nas florestas tropicais, e os efeitos da configuração espacial e qualidade do habitat assim como das atividades humanas atuais sobre a distribuição de mamíferos de maior porte em uma paisagem rural de Mata Atlântica. No primeiro capítulo, através de uma revisão da literatura sumarizamos e avaliamos a evidência empírica de que mamíferos estão envolvidos em cascatas tróficas em florestas tropicais com o objetivo de indicar os avanços, os problemas e os desafios nessa área. Poucos estudos empíricos e conceituais foram encontrados na literatura, todos realizados nas últimas três décadas, enquanto que a maioria dos estudos empíricos foi realizada nos Neotrópicos. Grande parte das hipóteses relacionadas a cascatas tróficas foi apenas proposta, e considera o homem como predador de topo. Além da maior parte das variáveis quantificadas não serem adequadas para demonstrar efeitos em cascata, a escala temporal da maioria dos estudos revisados foi curta para acessar estes efeitos sobre a comunidade de plantas que contém espécies longevas. Nenhuma hipótese abordou o efeito dos predadores de topo sobre as populações de presas pequenas via o controle da densidade e distribuição de mesopredadores. A maioria das hipóteses que encontramos na literatura se refere a outros efeitos indiretos causados por mamíferos, em particular através da dispersão de sementes e da disponibilização de nutrientes via fezes. Dessa maneira, demonstramos que o termo \"cascata trófica\" tem sido utilizado amplamente, englobando outros efeitos indiretos que se propagam via outras interações que não tróficas, e que a evidência empírica disponível até o momento de que mamíferos desencadeiam cascatas tróficas em florestas tropicais é pequena. No segundo capítulo, através da amostragem de 23 remanescentes florestais e do uso de modelos de ocupação e da abordagem de seleção de modelos, investigamos como fatores associados à configuração espacial e qualidade do habitat e a outras atividades humanas em andamento interagem e condicionam a distribuição de mamíferos terrestres de maior porte em paisagens intensamente modificadas pelo homem. A assembléia de mamíferos de maior porte encontrada na paisagem estudada é simplificada e dominada por mamíferos silvestres generalistas de médio porte, sugerindo que o controle de mesopredadores e a regeneração das florestas podem estar comprometidos. Os resultados também sugerem que: (1) a distribuição de mamíferos de maior porte deve ser condicionada mais por fatores associados à configuração espacial do que à qualidade do habitat florestal; (2) as atividades humanas atuais são tão ou mais importantes que a configuração espacial e a qualidade do habitat para a maioria das espécies. O tamanho dos fragmentos e a distância a rodovias, entre os fatores associados à configuração espacial, e a caça e a presença do cachorro doméstico, entre as atividades humanas atuais, foram particularmente importantes para a distribuição das espécies de mamíferos de maior porte. A relevância das atividades humanas em andamento sugere que estratégias de manejo que foquem em mudanças na atitude da população humana, através de programas de conscientização e educação, podem ter resultados significativos em termos da persistência de populações de mamíferos em paisagens rurais. / In this dissertation we investigated the role of large mammals in trophic cascades in tropical forests, and the effects of habitat configuration and quality as well as of current human activities on the distribution of large mammals in a rural Atlantic forest landscape. In the first chapter, through a literature review we summarized and evaluated the empirical evidence that mammals are involved in trophic cascades in tropical forest, with the aim of highlighting the progress, problems and challenges in this area. Few conceptual and empirical studies were found in the literature, all of which were performed in the last three decades, while most of the empirical studies were developed in the Neotropics. Most of the hypotheses related to trophic cascades were only proposed and not tested, and considered humans as top predators. Not only most of the quantified variables were not appropriate to demonstrate cascading effects, but also the temporal scale of most studies was short to detect these effects on plant communities composed of long-lived species. We did not find hypotheses addressing the effect of top predators on the populations of small prey through the control of mesopredator density and distribution. Most hypotheses in the reviewed literature refer to other indirect effects played by mammals, especially through seed dispersal and nutrient allocation via feaces. Thus, we demonstrate that the term \"trophic cascade\" has been used widely, encompassing other indirect effects that propagate through other, non-throphic interactions, and that the empirical evidence available so far that mammals are drivers of trophic cascades in tropical forest is weak. In the second chapter, through the sampling of 23 forest fragments and using occupancy models and a model selection approach, we investigated how factors associated with habitat configuration and quality and with other current human activities interact to define the distribution of terrestrial large mammals in human-modified landscapes. The large mammal assemblage from the studied landscape is impoverished and dominated by medium-sized generalist species, suggesting that both the control of mesopredators and forest regeneration may be compromised. Our results also suggest that: (1) the distribution of large mammals is determined mainly by aspects of habitat configuration rather than by aspects of habitat quality, and (2) current human activities are equally or more important than habitat configuration and quality for most of the species. Fragment size and distance to roads, among the factors associated with habitat configuration, and hunting pressure and domestic dog presence, among those associated with current human activities, were particularly important to the distribution of large mammal species. The relevance of current human activities suggests that management strategies that focus on changing people attitudes, through programs of education, can have significant results in terms of the persistence of mammal populations in rural landscapes.
10

Drobní zemní savci podél přirozených a antropogenních krajinných bariér / Small terrestrial mammals along natural and anthropogenic landscape barriers

BOHDAL, Tomáš January 2011 (has links)
The dissertation summarises the result of the study of small terrestrial mammals (Eulipotyphla, Rodentia) along natural (watercourses) and anthropogenic (road, highway) landscape barriers. It points to an interesting phenomenon of road drainage ditches as a transitional migration environment, further it assesses the level of locomotion activity, the rate of structure of subpopulations and the frequency of crossing watercourses in the case of selected rodent species. It contributes with its results to solving problems concerning the effect of these landscape structures on the species diversity, ground mobility or genetic structure of small terrestrial mammals. ˙˙˙˙

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