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Estrutura e composição de espécies arbóreas em um trecho de floresta ombrófila densa atlântica no litoral norte do estado de São Paulo e padrões de similaridade florística em escala regional /Prata, Eduardo Magalhães Borges. January 2009 (has links)
Orientador: Marco Antonio de Assis / Banca: Sergius Gandolfi / Banca: Natália Macedo Ivanauskas / Resumo: Este trabalho foi desenvolvido em um trecho de Floresta Ombrófila Densa Atlântica no Núcleo Picinguaba do Parque Estadual da Serra do Mar, litoral norte do Estado de São Paulo, município de Ubatuba-SP. A área de estudo corresponde a uma das parcelas amostrais (Parcela D) do Projeto Temático "Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virgínia do Parque Estadual da Serra do Mar" do Programa BIOTA-FAPESP. Nosso estudo foi estruturado em três capítulos. No Capítulo 1, objetivamos descrever a composição florística e a estrutura da comunidade arbórea em uma parcela de 1 ha; avaliar o padrão de distribuição espacial das espécies e; investigar a ocorrência de correlações entre a distribuição das espécies e as variáveis 'altitude média', 'desnível topográfico', 'cobertura rochosa', 'presença de água na superfície do solo', 'distância do rio' e 'luz no interior da parcela', através de uma CCA. No Capítulo 2, investigamos a distribuição da riqueza e da diversidade de espécies ao longo do perfil vertical, considerando os estratos adultos e regenerantes da comunidade, buscando responder em quais níveis de altura está presente o maior número de espécies arbóreas. No Capítulo 3, avaliamos a distribuição das espécies e os padrões de similaridade florística entre áreas de Floresta Ombrófila Densa das Terras Baixas e Submontana situadas ao longo de um gradiente latitudinal entre os Estados do Rio de Janeiro e Santa Catarina. Nossos resultados revelaram valores elevados de riqueza (161 spp) e diversidade (H' = 4,0) no hectare analisado. Observamos padrões de distribuição espacial aleatórios para a maioria das espécies na comunidade, onde apenas Euterpe edulis, Alsophila sternbergii e Coussarea meridionalis var. porophylla apresentaram padrão agregado... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study was conducted in a stretch of Atlantic Rain Forest at Núcleo Picinguaba do Parque Estadual da Serra do Mar, northern coast of São Paulo State, municipality of Ubatuba-SP. The study area represents one of the sample plots (Plot D) of the Project "Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virginia do Parque Estadual da Serra do Mar" Programa BIOTA-FAPESP. Our study was structured in three chapters. In Chapter 1, we aimed to describe the floristic composition and tree structure in a plot of 1 ha; assess the pattern of spatial distribution of species and, to investigate the occurrence of correlations between species distribution and the variables 'average height', 'topographic gap', 'cover rock ', 'presence of water on soil surface', 'distance from the river' and 'light in the interior of the plot', through a CCA. In Chapter 2, we investigated species richness and diversity distribution along the vertical profile, involving both regenerating and adult strata, in order to answer which height levels show the greatest number of tree species. In Chapter 3, we assessed species distribution and the occurrence of patterns on floristic similarities between areas of Lowlands and Submontanes Atlantic Rain Forests areas along a latitudinal gradient between Rio de Janeiro and Santa Catarina states. Our results revealed high richness (161 spp) and diversity (H' = 4.0) values in the area examined. We observed random patterns on spatial distribution for most species in the community, where only Euterpe edulis, Alsophila sternbergii and Coussarea meridionalis var. porophylla showed clumped patterns. Significant correlations between species and environmental variables matrices were detected for axis 1 of CCA (p = 0.001). The regenerating stratum showed greater floristic richness than adult stratum and higher values... (Complete abstract click electronic access below) / Mestre
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Physiological and Environmental Processes Influencing Growth Strategies in Amphibian LarvaeDahl, Emma January 2011 (has links)
Cost and benefits of high individual growth rates are likely to vary across different environments leading to geographic differentiation in growth strategies. In ectotherms, habitats constrained by short growing seasons favour rapid growth and development leading to adaptive latitudinal clines in these traits. Geographic variation in growth strategies should be influenced by physiological variation as well as environmental factors, however many of these mechanisms remain largely unexplored. In my thesis, I studied hormonal correlates of growth strategies, and compensatory responses to phenological variation and environmental stress in anuran tadpoles. I tested the hypotheses that fast growing high latitude common frog Rana temporaria tadpoles have higher growth hormone (GH) expression, and low stress hormone (CORT) elevation in response to predator stress. I found no relationship between GH expression and latitude, but CORT response decreased with latitude after 24 hours of predator exposure. Lower CORT response at high latitude can be adaptive as it may enable the tadpoles to maintain high growth in time constrained habitats. I also found that breeding phenology affected latitudinal variation in growth, development and anti-predator strategies. Northern R. temporaria tadpoles were phenotypically more similar to southern tadpoles when breeding occurred early, suggesting that part of the latitudinal variation is plastic and affected by yearly variation in phenology. When time stress was manipulated by delaying hatching, tadpoles were able to compensate by increasing their development and growth during the larval stage, decreasing the cost of the delayed development. In the final study, I found that northern tadpoles showed stronger compensatory growth during the larval stage than southern tadpoles after being delayed by low food, however, temperature manipulation did not induce differences in the compensatory responses. In general, my results highlight the roles of both environmental and genetic variation in determining individual growth strategies. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 735
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Estrutura e composição de espécies arbóreas em um trecho de floresta ombrófila densa atlântica no litoral norte do estado de São Paulo e padrões de similaridade florística em escala regionalPrata, Eduardo Magalhães Borges [UNESP] 27 March 2009 (has links) (PDF)
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prata_emb_me_rcla.pdf: 2137879 bytes, checksum: f0087a39dbca5bca9a452e4b2037187e (MD5) / Este trabalho foi desenvolvido em um trecho de Floresta Ombrófila Densa Atlântica no Núcleo Picinguaba do Parque Estadual da Serra do Mar, litoral norte do Estado de São Paulo, município de Ubatuba-SP. A área de estudo corresponde a uma das parcelas amostrais (Parcela D) do Projeto Temático “Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virgínia do Parque Estadual da Serra do Mar” do Programa BIOTA-FAPESP. Nosso estudo foi estruturado em três capítulos. No Capítulo 1, objetivamos descrever a composição florística e a estrutura da comunidade arbórea em uma parcela de 1 ha; avaliar o padrão de distribuição espacial das espécies e; investigar a ocorrência de correlações entre a distribuição das espécies e as variáveis ‘altitude média’, ‘desnível topográfico’, ‘cobertura rochosa’, ‘presença de água na superfície do solo’, ‘distância do rio’ e ‘luz no interior da parcela’, através de uma CCA. No Capítulo 2, investigamos a distribuição da riqueza e da diversidade de espécies ao longo do perfil vertical, considerando os estratos adultos e regenerantes da comunidade, buscando responder em quais níveis de altura está presente o maior número de espécies arbóreas. No Capítulo 3, avaliamos a distribuição das espécies e os padrões de similaridade florística entre áreas de Floresta Ombrófila Densa das Terras Baixas e Submontana situadas ao longo de um gradiente latitudinal entre os Estados do Rio de Janeiro e Santa Catarina. Nossos resultados revelaram valores elevados de riqueza (161 spp) e diversidade (H' = 4,0) no hectare analisado. Observamos padrões de distribuição espacial aleatórios para a maioria das espécies na comunidade, onde apenas Euterpe edulis, Alsophila sternbergii e Coussarea meridionalis var. porophylla apresentaram padrão agregado... / This study was conducted in a stretch of Atlantic Rain Forest at Núcleo Picinguaba do Parque Estadual da Serra do Mar, northern coast of São Paulo State, municipality of Ubatuba-SP. The study area represents one of the sample plots (Plot D) of the Project Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virginia do Parque Estadual da Serra do Mar Programa BIOTA-FAPESP. Our study was structured in three chapters. In Chapter 1, we aimed to describe the floristic composition and tree structure in a plot of 1 ha; assess the pattern of spatial distribution of species and, to investigate the occurrence of correlations between species distribution and the variables 'average height', 'topographic gap', 'cover rock ', 'presence of water on soil surface', 'distance from the river' and 'light in the interior of the plot', through a CCA. In Chapter 2, we investigated species richness and diversity distribution along the vertical profile, involving both regenerating and adult strata, in order to answer which height levels show the greatest number of tree species. In Chapter 3, we assessed species distribution and the occurrence of patterns on floristic similarities between areas of Lowlands and Submontanes Atlantic Rain Forests areas along a latitudinal gradient between Rio de Janeiro and Santa Catarina states. Our results revealed high richness (161 spp) and diversity (H' = 4.0) values in the area examined. We observed random patterns on spatial distribution for most species in the community, where only Euterpe edulis, Alsophila sternbergii and Coussarea meridionalis var. porophylla showed clumped patterns. Significant correlations between species and environmental variables matrices were detected for axis 1 of CCA (p = 0.001). The regenerating stratum showed greater floristic richness than adult stratum and higher values... (Complete abstract click electronic access below)
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Vztah mezi počtem druhů, teplotou, a úživností prostředí pro původní a nepůvodní druhy rostlin / Relationship between species diversity, temperature and productivity for native and non-native plant speciesSzostoková, Kateřina January 2016 (has links)
Latitudinal gradient of diversity is typically being explained by the three main hypotheses: The Resources Limitation Hypothesis, The Speciation Rate Hypothesis and The Niche Conservatism Hypothesis. In my study I tested basic assumptions of these hypotheses using native and non-native vascular plants obtained from the new database GloNAF (Global Naturalized Alien Flora). I tested an effect of precipitation, NPP, temperature and historical velocity (difference in temperature and precipitation between the Last Glacial Maximum and present) on species richness. Given that the distribution of non-native species is among continents irregular (we can divide them into two groups - Australia with Europe and North America and South America with Africa and Asia), I tested the abovementioned relationships at both - global and continental scale. Species richness of native species increased with NPP, precipitation and temperature and decreased with the difference in temperature. The global distribution of non-native plants increased with precipitation and temperature velocity and decreases with temperature and precipitation velocity, although the results varied for particular continents. Unlike other studies the number of non-native species didn't correlate with the number of native plant species. Concurrently...
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Life history and population dynamics of Eastern Sand Darter (Ammocrypta pellucida) in the lower Thames River, OntarioFinch, Mary January 2009 (has links)
Eastern Sand Darter (Ammocrypta pellucida) is listed as Threatened under the Canadian Species at Risk Act. Canadian populations are declining primarily due to the siltation of sandy depositional areas, the preferred habitat of the species. Little other relevant biological information is available for most Canadian populations and only limited information is available for populations in the United States. To supplement the paucity of information, this study collected biological information on A. pellucida during field surveys in 2006- 2007 from 10 sites located around the Big Bend Conservation Area in the lower Thames River, Ontario, Canada. Collected data were used to estimate critical life history traits including: longevity, fecundity, clutch size and number, growth, survival, age-at-first-maturity and cohort age structure. Longevity was 3+ years, with age-at-first-maturity being 1+ for both sexes. A minimum of 2 clutches, were laid per year with an average clutch size of 71 eggs. Average density within in the study area was 0.36 ± 0.11 A. pellucida/m². Quantitative comparison of lower Thames River biological information with a more southerly A. pellucida population in the Little Muskingum River, Ohio, demonstrated little latitudinal variation between the populations. Data comparison suggests that localized environmental factors are affecting biological characteristics, in particular water temperature that may be controlled by differences in riparian cover and/or groundwater input. Field derived life history information was used to create a Leslie matrix model which was used for population viability analysis. Perturbation analyses of reproductive scenarios involving changes in clutch numbers and size and age-at-first maturity found large variations in the finite rate of population growth. Elasticity analyses further indicated that 0+ survival and 1+ fertility were the limiting life history parameters. Thus allowing fish to survive until first reproduction would have the largest overall impact on improving population viability. Inclusion of environmental stochasticity in the model facilitated estimation of extinction probabilities in the range of 0.13 to 0.21 within 100 years. Based on the above, it is recommended that management activities for protection and restoration of A. pellucida focus on habitat protection of nursery and spawning areas.
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Life history and population dynamics of Eastern Sand Darter (Ammocrypta pellucida) in the lower Thames River, OntarioFinch, Mary January 2009 (has links)
Eastern Sand Darter (Ammocrypta pellucida) is listed as Threatened under the Canadian Species at Risk Act. Canadian populations are declining primarily due to the siltation of sandy depositional areas, the preferred habitat of the species. Little other relevant biological information is available for most Canadian populations and only limited information is available for populations in the United States. To supplement the paucity of information, this study collected biological information on A. pellucida during field surveys in 2006- 2007 from 10 sites located around the Big Bend Conservation Area in the lower Thames River, Ontario, Canada. Collected data were used to estimate critical life history traits including: longevity, fecundity, clutch size and number, growth, survival, age-at-first-maturity and cohort age structure. Longevity was 3+ years, with age-at-first-maturity being 1+ for both sexes. A minimum of 2 clutches, were laid per year with an average clutch size of 71 eggs. Average density within in the study area was 0.36 ± 0.11 A. pellucida/m². Quantitative comparison of lower Thames River biological information with a more southerly A. pellucida population in the Little Muskingum River, Ohio, demonstrated little latitudinal variation between the populations. Data comparison suggests that localized environmental factors are affecting biological characteristics, in particular water temperature that may be controlled by differences in riparian cover and/or groundwater input. Field derived life history information was used to create a Leslie matrix model which was used for population viability analysis. Perturbation analyses of reproductive scenarios involving changes in clutch numbers and size and age-at-first maturity found large variations in the finite rate of population growth. Elasticity analyses further indicated that 0+ survival and 1+ fertility were the limiting life history parameters. Thus allowing fish to survive until first reproduction would have the largest overall impact on improving population viability. Inclusion of environmental stochasticity in the model facilitated estimation of extinction probabilities in the range of 0.13 to 0.21 within 100 years. Based on the above, it is recommended that management activities for protection and restoration of A. pellucida focus on habitat protection of nursery and spawning areas.
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Ecological and Evolutionary Consequences of Herbivory in the Perennial Herb Lythrum salicariaLehndal, Lina January 2015 (has links)
In this thesis, I combined field, common-garden and greenhouse experiments to examine the ecological and evolutionary consequences of plant-herbivore interactions in the perennial herb Lythrum salicaria. More specifically I examined (1) whether resistance and tolerance to damage from herbivores vary with latitude and are positively related to the intensity of herbivory in natural populations, (2) whether effects of herbivory on plant fitness vary with latitude, (3) whether populations are locally adapted and whether herbivory influences the relative fitness of populations, and (4) whether the intensity and effects of insect herbivory on reproductive output vary locally along a disturbance gradient and are associated with differences in plant resistance. A common-garden and a greenhouse experiment demonstrated that plant resistance decreased whereas plant tolerance increased with latitude of origin among populations sampled along a latitudinal gradient in Sweden. Oviposition and feeding preference in the greenhouse and leaf damage in the common-garden experiment were negatively related to natural damage in the source populations. Experimental removal of insect herbivores in three populations sampled along the latitudinal gradient demonstrated that intensity of herbivory and its effects on plant fitness decreased towards the north. A reciprocal transplant experiment among the same three populations showed that herbivory affected the relative fitness of the three populations, but did not detect any evidence of local adaptation. Instead the southernmost population had the highest relative fitness at all three sites. A herbivore-removal experiment conducted in nine populations in an archipelago in northern Sweden demonstrated that insect herbivory strongly influenced among-population variation in reproductive output. However, variation in resistance was not related to differences in intensity of herbivory at this spatial scale. Taken together, the results demonstrate that resistance and tolerance to herbivory vary with latitude but in opposite directions, that intensity of herbivory is a major determinant of flowering and seed output, and that the strength of herbivore-mediated selection varies among populations in Lythrum salicaria. They further indicate that both physical disturbance regime and latitudinal variation in abiotic conditions may strongly influence the performance and abundance of perennial herbs because of their effects on interactions with specialized herbivores.
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BIOGEOGRAFIA DE MORCEGOS (CHIROPTERA) EM ÁREA DE TRANSIÇÃO FLORESTA-CAMPO NO SUDESTE DA AMÉRICA DO SUL / BIOGEOGRAPHY OF BATS (CHIROPTERA) IN FORESTGRASSLAND TRANSITION AREA IN THE SOUTHEASTERN OF SOUTH AMERICAWeber, Marcelo de Moraes 10 March 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The variation on the richness species in regional scales has been debated a
lot. Three of the hypotheses mot frequently discussed as determinants of regional
variability in richness species are energy, contemporary climatic conditions and
habitat heterogeneity. Studies at mesoscale are very important to discover different
patterns that underlying the variability in richness species. As the bats are so
common in whole world and ecologically diverse, these organisms are excellent
environmental characterized. On this basis, the goals of this study were to link the
bat species composition with the vegetation in forest-grassland transition area in the
Southeastern of South America and to assess the space influence on the bat species
richness by environmental variables. The study area includes the southeastern of
South America. Species distribution data were obtained by museums, review and
database on line .The distribution s estimate for each species was done on a map
with 139 cells 1º latitude by 1º longitude. It was collected distribution data to 79 bat
species. Rain Forest and Seasonal Forest had the largest species richness. The
cluster analysis based on the cells revealed three major clusters: the Forest cluster
(at north), the Araucaria cluster (at middle), and the Grassland cluster (at south). The
Araucaria cluster was associated to the Grassland cluster. The cluster analysis
based in the phytogeographic zones revealed four clusters, where the Araucaria
Forest was associated with the forested regions. The contemporary climatic
conditions hypothesis was the best explained the variability on the richness data,
where the mean annual temperature the main predictor variable, followed by extent
of relief and AET, respectively. With the whole variables, the OLS regression also
indicated the mean annual temperature as the main predictor variable, followed by
AET. These same variables also explained the variability in the species richness in
Phyllostomidae, Molossidae and Vespertilionidae. The Araucaria Forest is a filter
area to the dispersal of tropical species into subtropical and temperate areas of
South America, because the hard winters in that area, what may be explained likely
for the intolerance of some species in colder climates. / A variação da riqueza de espécies em escala regional tem sido
intensivamente discutida. Três das principais hipóteses que buscam explicar esse
padrão de variação são as hipóteses energética, climática e de heterogeneidade do
habitat. Estudos em meso-escala são importantes para descobrir padrões diferentes
que influenciam a variação na riqueza de espécies. Como os morcegos são muito
abundantes globalmente e bem diversificados ecologicamente, esses organismos
são ótimos caracterizadores ambientais. Com base nisso, os objetivos deste estudo
foram relacionar a composição das espécies de morcegos com a vegetação em área
de transição floresta-campo no sudeste da América do Sul e avaliar a influência do
espaço sobre a riqueza de morcegos através de variáveis ambientais. A área de
estudo compreende a porção sudeste da América do Sul. Os dados de distribuição
das espécies foram coletados através de visita a museus, revisão bibliográfica e
consulta a bancos de dados on line. Foi feita a estimativa de distribuição para cada
espécie sobre um mapa contendo 139 quadrículas de 1º de latitude por 1º de
longitude. Foram obtidos dados de distribuição para 79 espécies de morcegos.
Áreas de Floresta Ombrófila Densa e de Floresta Estacional possuíram a maior
riqueza de espécies. A análise de agrupamento com base nas quadrículas formou
três grupos nítidos: grupo Florestal (ao norte), Araucária (intermediário) e Campestre
(ao sul). O grupo Araucária ficou associado ao grupo Campestre. A análise de
agrupamento com base nas regiões fitogeográficas formou quatro grupos nítidos,
sendo que a Floresta de Araucária ficou associada às formações florestais. A
hipótese climática foi a que melhor explicou a variação dos dados de riqueza, sendo
a temperatura média anual a principal variável preditora, seguida pela amplitude da
altitude e pela AET, respectivamente. Considerando todas as variáveis, a regressão
OLS também apontou a temperatura média anual como a principal variável
preditora, seguida pela AET. Essas variáveis também explicaram a variação na
riqueza de espécies das famílias Phyllostomidae, Molossidae e Vespertilionidae. A
Floresta de Araucária é uma área filtro para a dispersão de espécies tropicais para
as regiões subtropicais e temperadas da América do Sul, devido aos invernos
rigorosos presentes nessa área, o que pode ser explicado principalmente pela
intolerância de algumas espécies a climas mais frios.
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Biotic factors drive bacterioplankton community in a tropical coastal site of the equatorial atlantic oceanKavagutti, Vinicius Silva 01 September 2016 (has links)
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Previous issue date: 2016-09-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The relationship between latitude and microbial diversity in the ocean is
controversial. Niche models predict higher richness at high latitudes in winter, while
snapshot field-sampling point towards higher richness at intermediate latitudes, with
lower values both towards equatorial and Polar Regions. However, given the dynamic
nature of ocean’s ecosystem it is difficult to account for temporal variations in empirical
assessments of microbial biodiversity. Here, we compared the components of diversity
(richness and evenness) and microbial population stability (coefficient of variation) in
two coastal ocean observatories with similar trophic state located in contrasting
latitudes, one located in the Equatorial Atlantic Ocean, and one temperate located in the
Northwestern Mediterranean Sea, to evaluate which factors drive the dynamics of
microbial communities in each site. Our observations support the view that, as animals
and plants, microbial communities exhibit higher (or at least similar) richness towards
the equator, at least in the coastal ocean. We also found evidence of increasing stability
with increasing evenness in tropical microbial communities when compared to the
temperate ones. Temperature and silicates drove temperate free-living prokaryotic
communities, while tropical ones were driven by stochastic factors such as biotic
interactions with eukaryotes. We propose a conceptual framework where microbial
community composition would be driven by deterministic factors in higher latitudes and
once the factor temperature is removed moving towards the equator, more stochastic
factors such as biotic interactions would emerge as the main factors shaping microbial
communities. This study highlights the importance of comparative studies on Eulerian
time-series distributed at different latitudes to fully understand the diversity patterns of
microbial communities in the ocean. / A relação entre a latitude e diversidade microbiana no oceano é controversa.
Modelos de nicho preveem maior riqueza em altas latitudes no inverno, enquanto
amostragens pontuais indicam uma maior riqueza em latitudes intermediárias, com
valores mais baixos para regiões equatoriais e polares. No entanto, dada a natureza
dinâmica do ecossistema oceânico, é difícil explicar variações temporais da
biodiversidade microbiana nas avaliações empíricas. Nesse trabalho comparamos os
componentes da diversidade (riqueza e equitabilidade) e estabilidade das populações
microbianas (coeficiente de variação) em dois observatórios oceânicos costeiros com
estados tróficos semelhantes, localizados em latitudes contrastantes: um localizado no
Oceano Atlântico Equatorial e um em clima temperado localizado no noroeste do Mar
Mediterrâneo, a fim de avaliar quais fatores estruturam a dinâmica das comunidades
microbianas em cada local. Observamos que tal como animais e plantas, as
comunidades microbianas exibem maior (ou pelo menos similar) riqueza no equador
pelo menos em águas costeiras. Também encontramos evidências de aumento da
estabilidade com o aumento da uniformidade nas comunidades microbianas tropicais,
quando comparadas com as de clima temperado. De modo geral, temperatura e silicatos
foram as variáveis que condicionaram as comunidades procariotas de vida livre no
observatório da região temperada, enquanto que no observatório tropical, fatores
estocásticos tais como interações bióticas com eucariotos, foram os fatores que mais
influenciaram as comunidades bacterianas. Assim, propomos um quadro conceitual
onde a composição da comunidade microbiana seria impulsionada por fatores
determinísticos em latitudes mais elevadas, enquanto que em latitudes menores, seriam
determinados por fatores mais estocásticos, como interações bióticas. Nosso estudo
destaca a importância de estudos comparativos utilizando series temporais Eulerianas
em diferentes latitudes para entender os padrões de diversidade das comunidades
microbianas no oceano.
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Severní a jižní limity areálů suchozemských měkkýšů Evropy na severojižním gradientu / On the Nothernmost and Southernmost Limits of European Land Snail Spatial RangesKřepelová, Lucie January 2011 (has links)
The aim of this work was to evaluate the limits of ranges of European land snail species along the north-south gradient. To work out the document it was necessary to prepare the set of digitalized maps, that enabled to create the database of ranges of the individual land snails species. Based on obtained data I tried to identify places where the northern and southern borders of species ranges are the most frequent. The landsnails' ranges are affected not only by particular life requirements of the individual species (potential limits), but also by other conditions, especially climatic, geographical and historical (truncated limits). In this work I focused on their differentiation. Above mentioned process also enabled me to track the north- south changes in species richness of the landsnails taking into consideration the truncated and potential limits. The most important natural barriers constraining that numerous of species cannot naturally widespread from the south to the north are the Scandinavian Mountains, the Alpes and the Carpathians and suprisingly also southern borders of german and polish lowlands. On the other hand, spreading of the species form the north to the south is limited only by the Alpes. I also tried to distinguish the group of species whose ranges are not influenced by these...
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