The purpose of this report was to investigate how the abiotic factors (temperature, pH, nutrients, oxygen levels and water content) would affect the decomposition of oil-contaminated soil and how a variance in structured soil would affect the decomposition-rate. A minor field-study was made and soil where structured in five different ways (one was a default pile and was used as a reference). The study took place over 137 days and three samples were taken (start, middle, end) and analyzed for aromatic and aliphatic compounds. The result of this study shows that there is a significant difference between all methods for the aliphatic compounds and no significant difference for the aromatic compounds. The abiotic factors that affect decomposition vary from organism to organism, depending on what type of environment it will function the best. In this type of environment it could be necessary to change temperature interval, nutrient availability or pH to optimize the conditions for the microorganisms. The conclusion of this report is that the structured of the soil-piles will affect decomposition rate, but it is unsure how much. Further research is needed to conclude how the soil should be structured to maximize the decomposition-rate.

Physical characteristics of a site that plant species inhabit may be useful in deriving the range of the species. Current range maps for tree species of the United States were originally developed by Elbert Little. These range maps were based primarily on observations. The purpose of this study was to update Little’s (Little, 1971) range maps of select southern oak species in Mississippi by calculating the topological, soil, and climatic features of sites using a Geographic Information System (GIS) to analyze environmental variables associated with species distributions. Data collected from databases were input into ArcMap and site data extracted using Hawth’s Analyst Tools. Stepwise logistic regression performed with site variables yielded the parameters used in predictive models to generate probability maps for each species across Mississippi. These probability maps demonstrate the potential to efficiently manage forests by giving a more encompassing view of species occurrence.

The use of nanoscale materials is growing exponentially, but there are also concerns about the environmental hazard to aquatic biota. Metal-containing engineered nanoparticles (NPs) are an important group of these new materials, and whilst there are undoubtedly a plethora of beneficial uses for these NPs, it is essential that an appropriate risk assessment is carried out in order to protect the environment and human health, with the consumption of contaminated fish a distinct possibility. The current study aimed to assess the bioavailability, uptake and toxicological effects of two metal-NPs (TiO2 NPs and Cu-NPs) to fish from both dietary and waterborne exposure routes and where appropriate compare them to their bulk counterpart. Whole body system effects were assessed along with the influences of the life stage of exposed fish and abiotic factors on toxicity. A technique to improve the quantification of Ti from TiO2 NPs in fish tissue was also developed. Effects from exposure to dietary TiO2 NPs manifested similarly to traditional dietary metal exposure, with no reduction in growth, but some sublethal affects. Exposure to waterborne Cu-NPs showed that rainbow trout were more acutely sensitive to CuSO4 than the NPs, but that despite limited uptake several body systems were affected (most notably ionoregulation). Larvae were more sensitive to CuSO4 than Cu-NPs, but no differences were seen with embryos, whilst larvae were more sensitive than embryos. Abiotic factors did have an effect on acute Cu-NP toxicity, though not always in a predictable manner, with some effects more pronounced than with CuSO4. Overall, it appears that metal-NPs are not as acutely toxic as their bulk counterparts, but sublethal effects, were routinely observed. As TiO2 NPs appear more toxic than its bulk counterpart, current legislation governing safe environmental limits may have to be adjusted, though the situation with Cu-NPs isn’t as clear and further investigation is required. However, the risk of human exposure via the consumption of NP contaminated fish fillets is extremely low.

Ce travail a porté sur l’étude de l’évolution des communautés zooplanctoniques à partir de séries temporelles de relevés effectués de 1995 à 2010 dans deux écosystèmes côtiers couplés, la Petite Rade de Toulon (PR) et Grande Rade de Toulon (GR) (Méditerranée Nord Occidentale, France) en relation avec les facteurs climatiques, les paramètres physiques et chimiques de l'eau et avec le phytoplancton. Le pas d’échantillonnage des relevés de zooplancton et du phytoplancton était d’un mois en moyenne. La maille du filet utilisé était de 90 µm, afin de cibler le mésozooplancton. La PR a différé de la GR dans son fonctionnement écologique, car elle est semi-fermée, mais aussi parce que l'activité anthropique y était beaucoup plus importante. Nos résultats ont montré que, de 1995 à 2010 dans les deux baies, l'abondance du zooplancton a sensiblement augmenté, surtout dans la PR. Il a été également établi, en utilisant différents outils statistiques, que la plus grande partie des espèces de zooplancton évolue de manière coordonnée chaque année, mais d’une manière différente d’une année à l’autre. C’est ce que nous avons appelé la signature annuelle, qui était très marquée dans la PR. Plusieurs paramètres environnementaux comme la température, l’oxygène, la salinité et l’ensoleillement, qui ont été simultanément enregistrés, expliquent cette signature annuelle. Il a été montré en effet qu’ils influencent très sensiblement la population de zooplancton, de manière instantanée ou avec un effet retardé. Les interactions responsables de cette évolution sont fort complexes, mais il a été aussi établi que ces facteurs sont plus forts lorsqu’ils agissaient de manière coordonnée. La répartition du zooplancton en groupes taxonomiques a montré que la diversité a augmenté jusqu’en 2005, puis a diminué légèrement, tout en restant à des niveaux plus élevés qu’en 1995. L’étude détaillée de la diversité, avec une classification des indices eux-mêmes, a fait l’objet du dernier chapitre. Enfin, nous émettons l’hypothèse que la diminution des stocks de poissons au cours des dernières décennies dans toute la région a entraîné une diminution des taux de prédation sur les communautés zooplanctoniques, ce qui peut expliquer l’augmentation de peuplements zooplanctoniques au cours de ces dernières années. Cet accroissement de l’abondance du zooplancton a pu entraîner à son tour une diminution de la biomasse du phytoplancton. Cette diminution a été parallèlement observée par notre équipe. Ceci suggère un système de contrôle top-down du réseau trophique. / This work focused the study of the evolution of zooplankton communities from time series of surveys conducted from 1995 to 2010 in two coastal coupled ecosystems, Little Bay (PR) and Large Bay (GR) of Toulon (North Western Mediterranean Sea, France) in relation to climatic factors, physical and chemical water parameters and phytoplankton. The samplings surveys of zooplankton, and indeed also of phytoplankton, were a month, on average. The net mesh size used was 90 µm to target Mesozooplankton. The PR differed from the GR in its ecological functioning, because it is semi-closed, but also because human activity is much more important. Our results showed that, from 1995 to 2010 in both bays, zooplankton abundance increased substantially, especially in the PR. It was also established, using statistical tools, that most zooplankton species evolved coordinated each year, but in a different way from one year to another. This is what we call the annual signature, which was more pronounced in the PR. Several environmental parameters such as temperature, oxygen, salinity and sunlight, which were simultaneously recorded, explained this annual signature. It was shown that they significantly influenced the population of zooplankton, instantly or with a delayed effect. Interactions responsible for this development are complex, but it was also established that these factors were stronger when they acted in a coordinated manner. Distribution of zooplankton taxonomic groups showed diversity increases until 2005 and then decreased slightly, while remaining at levels higher than in 1995. The detailed study of diversity, with a classification of the clues themselves was the subject of the last chapter. Finally, we hypothesize that the decline of fish stocks in recent decades throughout the region, resulting in lower rate of predation on zooplankton communities, may explain the increase of zooplankton communities in recent years. This increase in zooplankton abundance could in turn lead to a decrease in phytoplankton biomass. The decrease of phytoplankton was at the same time observed by our team. The latter hypothesis suggests a top-down control of the the food web

In the present M. Sc. thesis the effect of water temperature (thermal range: 17.4 - 38.6 °C) on early life history (during interval from egg fertilization to full yolk sac depletion by 50 % of larvae; Fe - Re50) in African catfish (Clarias gariepinus) was examined. Length of the incubation period (i. e. interval from egg fertilization to the moment of hatching of 50 % of individuals; Fe - H50), length of the hatching period (i. e. interval from hatching of 5 % of individuals to hatching of 95 % of individuals; H5 - H95), length of the period up to the first intake of exogenous food (i. e. interval from H50 to the first intake of exogenous food by 50 % of individuals; H50 - S50) and length of the period up to the full yolk sac resorption (H50 - Re50) were inversely proportional to the incubation temperature. Period of the yolk sac resorption was significantly prolonged (approximately six times) because of using of exogenous food (compared to treatments without added external food supplies). Embryonic development was theoretically stopped at temperature 15.4 °C and hatching occured after c. 12 effective day-degrees. Size of larvae increased during embryonic and larval period. Size of larvae at H50, S50 and Re50, was inversely proportional dependent on the incubation temperature. Size of individuals at Re50 was increased (approximately twice) because of using of exogenous food (compared to treatments without added external food supplies). Yolk sac volume (YsV) decreased during embryonic and larval period. YsV at H50 was correlated with size of egg and YsV was S50 was inversely proportional to the incubation temperature. A dry weight of yolk sac at H50 represented c. 89 % of total dry weight of hatched larvae. During the period of endogenous feeding c. 75 % of dry weight of egg was converted into the larval somatic tissues. Efficiency of energy conversion during the period of endogenous feeding is lower (60 %). The energetical value of total dry matter and content of sulfur in dry matter was decreasing during the period of endogenous feeding (in order: egg, hatched larvae, larvae at Re50). Content of nitrogen and carbon in dry matter was increasing during the embryonic period and afterwards was decreasing during the larval period. In term of survival, the zone of thermal tolerance for early life history in African catfish ranges from 19 to 33 °C (with thermal optimum between 23 and 30 °C), i. e. this fish belongs to the typical thermophilous species. The suboptimal temperatures lies within intervals 21 - 23 °C and 30 - 33 °C, respectively. Temperatures below 17.5 °C as well above 35.5 °C can be considered as the lethal temperatures already during embryonic period and those below 19 °C and above 33 °C as the lethal ones during larval period, respectively. In term of bioenergy, the thermal optimum for early life history in African catfish lies between 23 - 28 °C.

Submitted by Rosana Amâncio (rosana.amancio@ufcg.edu.br) on 2018-07-12T21:32:30Z No. of bitstreams: 1 EDCLEBESON BERTO DE SOUSA - DISSERTAÇÃO PPGCNBio 2016..pdf: 1801961 bytes, checksum: fe198d82ea402e4567249d7728cf5868 (MD5) / Made available in DSpace on 2018-07-12T21:32:30Z (GMT). No. of bitstreams: 1 EDCLEBESON BERTO DE SOUSA - DISSERTAÇÃO PPGCNBio 2016..pdf: 1801961 bytes, checksum: fe198d82ea402e4567249d7728cf5868 (MD5) Previous issue date: 2016-07-14 / CNPq / O Filo Nematoda compreende as maiores abundâncias e densidades em vários ecossistemas, por englobar animais cujas características morfológicas são adaptáveis aos diversos tipos de habitats bentônicos, incluindo praias arenosas. Estes ambientes são bastante explorados, mas não existe nenhum dado registrado para o litoral da Paraíba sobre a comunidade estudada em nível específico. O presente trabalho objetivou caracterizar taxonomicamente e ecologicamente a comunidade nematofaunística de quatro praias urbanas do litoral da Paraibana. Uma única coleta foi realizada em outubro de 2013, em cada praia foram estabelecido 3 pontos distintos, seguindo a linha da água, no médio litoral, com 10cm de profundidade no sedimento, as amostras coletadas foram fixadas com formol salino 4%. As amostras foram lavadas em água corrente utilizando uma peneira com malha de 0,044 mm e material retido foi transferido a um béquer. Os Nematoda foram triados em placa de Dolffus, diafanizados, identificados e medidos em nível de gênero e espécie com auxilio de um microscópio binocular, munido de câmera clara. Nematoda representou mais de 90% da meiofauna estudada. Foram encontradas 6 ordens, 13 famílias e 26 gêneros, dentre eles Phanodermelha, Nemmanema e Rhabdodemania foram aqui registrados pela primeira vez para praias do Brasil. Foram identificadas 22 espécies, 4 novas para ciência. A maior densidade esteve relacionada à Calomicrolaimus que foi representado unicamente pela espécie Calomicrolaimus rugatus. Os valores de diversidade e dominância como também a riqueza total, variaram entre as praias. A estrutura trófica apresentou uma maior abundância na tipologia 1B seguido de 2B. O estágio de desenvolvimento foi dominado por juvenis. O ANOSIM mostrou que há diferenças significativas entre as praias. Na análise de ordenação do MDS foi formado um grupo separando a praia do Bessa das demais. As espécies que mais contribuíram para as dissimilaridades foram Mesacanthion rigens, Bathylaimus parafilicaudatus, Pseudosteineria sagittispiculata, Pseudosteineria horrida, Calomicrolaimus rugatus e Theristus complexus, analisado pelo SIMPER. Dentre as variáveis ambientais, areia muito grossa foi a que mais se correlacionou com a estrutura da comunidade. Os gêneros e as espécies mantiveram o mesmo padrão de densidade, estrutura trófica, dominância entre as praias prospectadas. Dessa forma, a estrutura da comunidade foi distribuída de acordo com os fatores abióticos estudados. / The phylum Nematoda comprehends the largest abundances and densities in several ecosystems, by gathering animals whose morphological features are adaptable to the many types of benthic habitats, including sandy beaches. These environments are quite explored, but there is no data recorded to the coast of Paraiba on the studied community in specific level. This study aimed to characterize taxonomically and ecologically the nematofauna community of four urban beaches of Paraiba coast. A single sample was realized in October 2013, in each beach three distinct points were established, following the line of the water, in the middle coast, with 10 centimeters deep in the sediment, the samples were fixed with 4% saline formaldehyde. The samples were washed in running water using a sieve with a mesh of 0.044 mm and retained material was transferred to a beaker. The Nematoda were screened in a Dolffus plate and diaphanized, identified and measured at genus and species with the aid of a binocular microscope equipped with clear camera. Nematoda represented more than 90% of the meiofauna which was studied. We found 6 orders, 13 families and 26 genera, including Phanodermelha, Nemmanema and Rhabdodemania that were reported here for the first time to the beaches in Brazil. We identified 22 species, 4 of them which are new to science. The highest density was related to Calomicrolaimus which was represented only by the species Calomicrolaimus rugatus. The values of diversity and dominance as well as the total wealth, ranged among the beaches. The trophic structure presented a higher abundance in the type 1B followed by 2B. The development stage was dominated by juveniles. The ANOSIM showed that there are significant differences among the beaches. In MDS ordination analysis a group was formed, separating Bessa beach from the others. The species that mostly contributed to the dissimilarities were Mesacanthion rigens, Bathylaimus parafilicaudatus, Pseudosteineria sagittispiculata, Pseudosteineria horrida, Calomicrolaimus rugatus and Theristus complexus, analyzed by SIMPER. Among the environmental variables, very coarse sand was the most correlated with the community structure. The genera and species maintained the same pattern density, trophic structure and dominance among the prospected beaches. Thus, the community structure was distributed according to the abiotic factors studied.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Currently comes increasing the interest with agronomical emphasis by native forest species from Brazil, due its applications in various sectors of the economy. The âtamborilâ (Enterolobium contorsiliquum (Vell.) Morong) is one of these species, presenting importance for the timber, landscape, medical, beekeeping sector, beyond to be indicated for recovery of degraded large areas. The objective of this work was studying the seeds germination and seedlings growth of E. contorsiliquum in function of seeds weight, location on fruit and conditions of temperature and light. Two experiments were conducted: in the first, the seeds were separated according to the weight, in three classes (light, intermediaries and heavy), submitting each class to germination test under absence and presence of light in four different temperatures (20, 30, 40 and 20-30ÂC). This experiment was disposed in triple factorial squeme 3x2x4 (related to three classes, two light regimes and four temperatures) under completely randomized design, with four replications. In the second, the seeds were separated according to their location in the fruit (proximal, central and distal regions) and submitted to germination test under the temperatures of 25 and 20-30ÂC, using factorial squeme 3x2 (three locations and two temperatures) in completely randomized design with four replications. For both experiments were determined the variables: germination first count, final percentage and rate, length and dry weight of shoot, root and total, beyond of accelerated aging only for the second experiment. All data were submitted to normality test and, when they were presented normal was performed variance analysis and the compare means by Tukey test, when no normal only Mann-Whitney test. The germination of âtamborilâ was shown to be insensitive to light with high percentage and rate when using the temperature of 40ÂC, however this temperature detracted the seedlings development. So the temperature more indicated for the settlement of âtamborilâ is 30ÂC. The heavy seeds had always the best results, showing the use of these seeds ensures seedlings production more uniform and with good development. Among the variables assessed the location of the seeds influenced only the germination rate, which was higher for seeds of the distal region of the fruit at 25ÂC. Conclude also the alternating temperature doesnât affect the seeds germination and seedlings growth of âtamborilâ. / Atualmente vem crescendo o interesse com cunho agronÃmico pelas espÃcies florestais nativas do Brasil, em virtude de suas aplicaÃÃes em diversos setores da economia. O tamboril (Enterolobium contorsiliquum (Vell.) Morong) à uma destas espÃcies, apresentando importÃncia para o setor madeireiro, paisagÃstico, medicinal, melÃfero, alÃm de ser indicada para recomposiÃÃo de Ãreas degradadas. O objetivo deste trabalho foi estudar a germinaÃÃo de sementes e o crescimento de plÃntulas de tamboril em funÃÃo do peso, localizaÃÃo das sementes no fruto e condiÃÃes de temperatura e luz. Foram realizados dois experimentos: no primeiro, as sementes foram separadas de acordo com o peso, em trÃs classes (leves, mÃdias e pesadas), submetendo-se, cada classe, ao teste de germinaÃÃo sob ausÃncia e presenÃa de luz em quatro diferentes temperaturas (20, 30, 40 e 20-30ÂC). Este experimento foi disposto em esquema fatorial triplo 3x2x4 (referentes a trÃs classes, dois regimes de luz e quatro temperaturas) sob delineamento inteiramente casualisado, com quatro repetiÃÃes. No segundo, as sementes foram separadas de acordo com sua localizaÃÃo no fruto (regiÃes proximal, central e distal) e submetidas ao teste de germinaÃÃo sob as temperaturas de 25 e 20-30ÂC, utilizando-se esquema fatorial 3x2 (trÃs locais e duas temperaturas) em delineamento inteiramente casualisado com quatro repetiÃÃes. Para ambos os experimentos foram determinadas as variÃveis: primeira contagem, porcentagem final e Ãndice de velocidade de germinaÃÃo, comprimento e massa seca da parte aÃrea, raiz e total das plÃntulas, alÃm do envelhecimento acelerado para o segundo experimento. Todos os dados foram submetidos a teste de normalidade e, quando estes apresentaram-se normais realizou-se anÃlise de variÃncia e a comparaÃÃo das mÃdias pelo teste de Tukey, quando nÃo normais apenas teste de Mann-Whitney. A germinaÃÃo de tamboril mostrou-se insensÃvel à luz com alta porcentagem e velocidade quando utilizou-se a temperatura de 40ÂC, todavia esta temperatura prejudicou o desenvolvimento das plÃntulas. Assim a temperatura mais indicada para o estabelecimento de tamboril à a de 30ÂC. As sementes pesadas obtiveram sempre os melhores resultados, mostrando que a utilizaÃÃo destas sementes garante produÃÃo de mudas mais uniforme e com bom desenvolvimento. Dentre as variÃveis avaliadas, a localizaÃÃo das sementes influenciou apenas a velocidade de germinaÃÃo, a qual foi maior para as sementes da regiÃo distal do fruto a 25ÂC. Conclui-se tambÃm que a alternÃncia de temperatura nÃo afeta a germinaÃÃo e crescimento das plÃntulas de tamboril.

Made available in DSpace on 2016-02-26T14:53:14Z (GMT). No. of bitstreams: 1 MarleiLinoSantos.pdf: 344154 bytes, checksum: 5e98ff1698e6b3ad31d2c99184636ca4 (MD5) Previous issue date: 2009-04-17 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Flowering entomofauna in Peltophorum dubium (Spreng.) Taub. in the area of Dourados, MS. Floral biology, reproduction system and insects visiting, were studied in P.dubium, being observed the diversity, frequency, abundance and constancy of species visiting at different hours. The flowers possess diurnal anthesis, sweetened odor, and the concentration of sugar in the nectar was of 34%. The results of reproduction system suggest that P. dubium is autocompatible, however, the xenogamy was the predominant system of reproduction. During its flowering period, it was verified a great diversity of floral visitors belonging to five orders, being most constituted by bees. The medium presence of visiting among the different hours in the period of the 06h:00min. to the 16h:00min. didn't present significant difference, decreasing up to the 17h:00min. The environmental factors (temperature, relative humidity, wind velocity and luminosity) influenced the frequency and distribution of the insects. As for the behavior in relation to the flower, it was observed that Xylocopa sp., Bombus sp. and Oxaea flavescens Klug, 1807 they possess size and appropriate behavior to the pollination of P. dubium being considered legitimate pollinators. The other bees, Apis mellifera Linnaeus, 1758, Augochloropsis sp.2 e sp.3, Trigona spinipes Fabricius, 1793, Geotrigona mombuca Smith, 1863, Scaptotrigona depilis Moure, 1942 and Exomalopsis sp.3 were considered occasional pollinators or nectar thieves / RESUMO: Entomofauna visitante de Peltophorum dubium (Spreng.) Taub. na região de Dourados MS. A biologia floral, sistema de reprodução e entomofauna visitante, foram estudados em P. dubium, observando-se as diversidade, freqüência, abundância e constância das espécies visitantes em diferentes horários. As flores possuem antese diurna, odor adocicado, e a concentração de açúcar no néctar foi de 34%. Os resultados de sistema de reprodução sugerem que P. dubium é autocompatível, porém, a xenogamia foi o sistema de reprodução predominante. Durante a floração da espécie, verificou-se uma grande diversidade de visitantes florais pertencentes a cinco ordens, sendo a maioria constituída por abelhas. A presença média de visitantes entre as diferentes horas no período das 06h:00min. as 16h:00min não apresentou diferença estatisticamente significativa, diminuindo até as 17h:00 min. Os fatores ambientais (temperatura, umidade relativa, velocidade do vento e luminosidade) influenciaram a freqüência e distribuição dos insetos. Quanto ao comportamento forrageador em relação à flor, observou-se que Xylocopa sp., Bombus sp. e Oxaea flavescens Klug, 1807 possuem tamanho e comportamento adequados à polinização de P. dubium sendo considerados polinizadores legítimos. As demais abelhas, Apis mellifera Linnaeus, 1758, Augochloropsis sp.2 e sp.3, Trigona spinipes Fabricius, 1793, Geotrigona mombuca Smith, 1863, Scaptotrigona depilis Moure, 1942 e Exomalopsis sp.3 foram considerados polinizadores ocasionais ou pilhadores

Orientador: Gustavo Quevedo Romero / Texto em português e inglês / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T16:18:04Z (GMT). No. of bitstreams: 1 Omena_PaulaMunhoz_D.pdf: 3562543 bytes, checksum: 5d44970e0b040040755da9a84ed62a42 (MD5) Previous issue date: 2014 / Resumo: Com a intensificação das transformações dos sistemas naturais pela atividade humana, o entendimento dos processos que afetam as comunidades e o funcionamento dos ecossistemas tornou-se um tema central para a ecologia contemporânea. As interações entre as espécies, bem como as interações entre as espécies e os componentes abióticos do meio ambiente, afetam tanto os padões de diversidade biológica como funções ecossistêmicas. Neste trabalho, buscou-se compreender o papel relativo das interações predador-presa e dos componentes abióticos sobre as propriedades das comunidades e funcionamento dos ecossistemas. No primeiro capítulo, investiguei o papel do tamanho do habitat sobre os efeitos de predadores terrestres na estrutura de comunidades e funcionamento de ecossistemas adjacentes. O tamanho do habitat modera cascatas tróficas dentro de ecossistemas, deste modo, esperei que efeitos similares do tamanho do habitat poderiam afetar cascatas tróficas que ocorrem através dos limites dos ecossistemas. No segundo capítulo, explorei predições relacionadas a variação no formato de pirâmides tróficas de biomassa ao longo de gradientes ambientais (tamanho do habitat, concentração de detritos e produtividade). Além disso, investiguei a contribuição relativa dos efeitos de consumo direto e do risco de predação nas interações predador-presa como mecanismos estruturadores de pirâmides tróficas de biomassa. No terceiro capítulo, tive como objetivo investigar os efeitos de dois extremos de um gradiente ambiental e os efeitos de predadores sobre os componentes da diversidade de presas detritívoras (i.e., diversidade funcional, filogenética e taxonômica). Além disso, explorei o papel relativo do ambiente, dos predadores e dos componentes da diversidade sobre o funcionamento ecossistêmico (i.e., decomposição e fluxo de nitrogênio). Os resultados encontrados nos três capítulos demonstram que fatores abióticos são cruciais na determinação das propriedades das comunidades, interações predador-presa e, consequentemente, no funcionamento ecossistêmico. O papel relativo dos efeitos cascatas de predadores é altamente dependente das condições ambientais que medeiam as interações entre predadores e presas / Abstract: In the face of the increasing transformation of environmental conditions by human activity, understanding the processes that affect communities and ecosystem functioning has become fundamental goals in ecology. The interactions between coexisting species and, their interactions with the abiotic components of environment, affect the patterns of biological diversity and functions of ecosystems. In this study, I sought to understand the relative role of predator-prey interactions and of abiotic factors on the communities¿ properties and ecosystem functioning. In the first chapter, I investigated the role of habitat size in mediating the effects of terrestrial predators on the structure of communities and the functioning of adjacent ecosystems. Habitat size mediated trophic cascades within ecosystems; therefore, I expected that similar effects of habitat size affect cross-ecosystem trophic cascades. In the second chapter, I explored predictions related to the variation of trophic pyramids of biomass across environmental gradients (i.e., habitat size, detritus concentration and productivity). Furthermore, I investigated the relative contribution of consumptive and non-consumptive effects of predators on the shape of trophic pyramids of biomass. In the third chapter, I sought to investigate the effects of two extremes of an environmental gradient and the effects of predators on the components of detritivores diversity (i.e., functional, phylogenetic and taxonomic). Moreover, I explored the relative role of environment, predators and detritivore diversity components on the functioning of ecosystems (i.e., detritus processing and nitrogen flux). The results from this study demonstrated that abiotic factors are crucial determinants of community properties, predator-prey interactions and ecosystem functioning. The relative role of the predators cascading effects are strongly dependent on the environmental conditions which mediate the interactions between predators and prey / Doutorado / Ecologia / Doutora em Ecologia

Orientador: Luciana Lasry Benchimol Reis / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T21:57:40Z (GMT). No. of bitstreams: 1 Perseguini_JulianaMoriniKupperCardoso_D.pdf: 12546958 bytes, checksum: 39944eda3d8791dd247ca42277bb68df (MD5) Previous issue date: 2013 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Doutorado / Genetica Vegetal e Melhoramento / Doutora em Genética e Biologia Molecular