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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.
31

Corredores de fauna na região Cantareira-Mantiqueira: evidências geográficas / Fauna corridor in the Cantareira-Mantiqueira region: geographic evidences

Mazzei, Katia 05 September 2007 (has links)
A Política Nacional do Meio Ambiente completou 25 anos em 2006. Houve muitos avanços no planejamento ambiental tanto para criação de Unidades de Conservação como para o processo de licenciamento ambiental de atividades de grande porte, por meio do Estudo de Impacto Ambiental e suas decorrências. Por outro lado, em muitos aspectos do planejamento, a fauna foi ignorada ou abordada com superficialidade. Neste trabalho, considera-se a ampla distribuição histórica de felinos na américa do sul e evidencia-se a existência de felinos de grande porte (Puma concolor) e dos pequenos gatos selvagens na região entre as rodovias Fernão Dias e Presidente Dutra no Estado de São Paulo. Evidencia-se, também um mosaico de usos da terra que formam um expressivo corredor para a fauna e embasam a discussão para o necessário avanço das ferramentas de planejamento que ainda carecem de normatizações e parâmetros básicos à conservação de felinos. Propõe-se uma matriz qualitativa de avaliação de impactos ambientais e monitoramento de obras lineares para felinos. / The National Policy of the Environment completed 25 years in 2006. There were several advances in the environmental planning both for the creation of Conservation Units and for the process of environmental licence of far-reaching activities, through Environmental Impact Study and its results. On the other side, in many aspects of the planning, the fauna was ignored or tackled with superficiality. In this work, it is considered the broad historical distribution of the felines in South America and it is showed the existence of big felines (Puma concolor) and small wild cats in the region between the highways Fernão Dias and Presidente Dutra, in the State of São Paulo. It is showed as well a mosaic of land uses that constitutes an important fauna corridor and supports the discussion for the necessary advance of the planning tools that still need standardization and basic parameters for the felines conservation. It is proposed a qualitative evaluation mould for environmental impacts and linear constructions for felines.
32

A Fauna Vagil de Sargassum Cymosum C. Agardh, 1820 daPraia do Lamberto e Praia Grande, Ubatuba, Sao Paulo,Com Especial Referencia aos Gammaridea (Crustacea -Aph / The mobile fauna, epecially grammaridea, of sarygassum cymosum, 1820 from Lamberto and Praia Grande shores.

Tararam, Airton Santo 14 February 1977 (has links)
Foram feitas comparações na composição da fauna vágil de duas praias de intensidades de ondas diferentes. Coletas mensais da amostra de alga foram feitas durante o período de julho/74 a junho/75 na Praia do Lamberto (abrigada) e Praia Grande (exposta). Foi dada mais ênfase aos Gammaridea por serem dominantes - dentre 26 taxa coletados. Foram discutidas as relações entre as algas e estes Crustacea. Estudos do aspecto morfológico mostraram que algumas espécies de Gammaridea estão mais adaptadas na praia agitada e outras na protegida. Na Praia Grande algumas espécies tiveram suas maiores freqüências na primavera e verão e na Praia do Lamberto elas se deram em épocas diferentes. Baseando-se na diversidade de espécies e na similaridade média encon-trada para os Gammaridea, parece não haver diferenças marcantes entre os dois pontos de coleta. / The mobile C. Agardh, fauna of Sargassum cymosum 1820 of \"Praia do Lamberto\" and \"Praia Grande\", Ubatuba, São Paulo, with special reerence to Gammaridea (Crustacea - Amphypoda) A comparative study on the composition of the mobile fauna associated to Sargassum cymosum from two localities, one sheltered (Praia do Lamberto) and another exposed (Praia Grande) has been made. Samples of the algae were collected monthly from July/1974 to June/1975. Gammaridea was dominant arnong. 26 collected taxa. The relationship between algae and Gammaridea is discussed. The study of the orphological aspects of this Crustacea showed that some species seem to be more adapted to living in sheltered locality and others in exposed ones. The species had their highest frequency in different seasons at both localities. The diversity of species and medium similarity of Gammaridea showed that no conspicuous differences between the two localities occur.
33

Corredores de fauna na região Cantareira-Mantiqueira: evidências geográficas / Fauna corridor in the Cantareira-Mantiqueira region: geographic evidences

Katia Mazzei 05 September 2007 (has links)
A Política Nacional do Meio Ambiente completou 25 anos em 2006. Houve muitos avanços no planejamento ambiental tanto para criação de Unidades de Conservação como para o processo de licenciamento ambiental de atividades de grande porte, por meio do Estudo de Impacto Ambiental e suas decorrências. Por outro lado, em muitos aspectos do planejamento, a fauna foi ignorada ou abordada com superficialidade. Neste trabalho, considera-se a ampla distribuição histórica de felinos na américa do sul e evidencia-se a existência de felinos de grande porte (Puma concolor) e dos pequenos gatos selvagens na região entre as rodovias Fernão Dias e Presidente Dutra no Estado de São Paulo. Evidencia-se, também um mosaico de usos da terra que formam um expressivo corredor para a fauna e embasam a discussão para o necessário avanço das ferramentas de planejamento que ainda carecem de normatizações e parâmetros básicos à conservação de felinos. Propõe-se uma matriz qualitativa de avaliação de impactos ambientais e monitoramento de obras lineares para felinos. / The National Policy of the Environment completed 25 years in 2006. There were several advances in the environmental planning both for the creation of Conservation Units and for the process of environmental licence of far-reaching activities, through Environmental Impact Study and its results. On the other side, in many aspects of the planning, the fauna was ignored or tackled with superficiality. In this work, it is considered the broad historical distribution of the felines in South America and it is showed the existence of big felines (Puma concolor) and small wild cats in the region between the highways Fernão Dias and Presidente Dutra, in the State of São Paulo. It is showed as well a mosaic of land uses that constitutes an important fauna corridor and supports the discussion for the necessary advance of the planning tools that still need standardization and basic parameters for the felines conservation. It is proposed a qualitative evaluation mould for environmental impacts and linear constructions for felines.
34

A Fauna Vagil de Sargassum Cymosum C. Agardh, 1820 daPraia do Lamberto e Praia Grande, Ubatuba, Sao Paulo,Com Especial Referencia aos Gammaridea (Crustacea -Aph / The mobile fauna, epecially grammaridea, of sarygassum cymosum, 1820 from Lamberto and Praia Grande shores.

Airton Santo Tararam 14 February 1977 (has links)
Foram feitas comparações na composição da fauna vágil de duas praias de intensidades de ondas diferentes. Coletas mensais da amostra de alga foram feitas durante o período de julho/74 a junho/75 na Praia do Lamberto (abrigada) e Praia Grande (exposta). Foi dada mais ênfase aos Gammaridea por serem dominantes - dentre 26 taxa coletados. Foram discutidas as relações entre as algas e estes Crustacea. Estudos do aspecto morfológico mostraram que algumas espécies de Gammaridea estão mais adaptadas na praia agitada e outras na protegida. Na Praia Grande algumas espécies tiveram suas maiores freqüências na primavera e verão e na Praia do Lamberto elas se deram em épocas diferentes. Baseando-se na diversidade de espécies e na similaridade média encon-trada para os Gammaridea, parece não haver diferenças marcantes entre os dois pontos de coleta. / The mobile C. Agardh, fauna of Sargassum cymosum 1820 of \"Praia do Lamberto\" and \"Praia Grande\", Ubatuba, São Paulo, with special reerence to Gammaridea (Crustacea - Amphypoda) A comparative study on the composition of the mobile fauna associated to Sargassum cymosum from two localities, one sheltered (Praia do Lamberto) and another exposed (Praia Grande) has been made. Samples of the algae were collected monthly from July/1974 to June/1975. Gammaridea was dominant arnong. 26 collected taxa. The relationship between algae and Gammaridea is discussed. The study of the orphological aspects of this Crustacea showed that some species seem to be more adapted to living in sheltered locality and others in exposed ones. The species had their highest frequency in different seasons at both localities. The diversity of species and medium similarity of Gammaridea showed that no conspicuous differences between the two localities occur.
35

An Analysis of Population Connectivity in Lotic Fauna: Constraints of Subdivision for Biotic Responses to Stream Habitat Restoration

Cook, Benjamin Douglas, n/a January 2007 (has links)
Connectivity in ecological systems is a broad concept that embodies the transmission of ecosystem components throughout landscapes at multiple spatial and temporal scales. Of relevance to the present study are the connections (or lack thereof) among local populations of stream fauna - population connectivity in lotic systems. Dispersal, recolonisation and migration are the demographic forms of population connectivity, and gene flow is the genetic aspect of population connectivity. Both forms of population connectivity have underpinned some of the classic theories and hypotheses in stream ecology, and have implications for pure and applied stream ecology, including ecosystem restoration. Conceptual models in ecology can facilitate understanding and predictability of the ecosystem processes they represent, and have potential applicability as management tools or 'rules of thumb' in conservation and restoration programs. Various theoretical models describe potential patterns of connectivity among local populations and in this thesis these models were used to evaluate population connectivity in a freshwater fish (southern pygmy perch, Nannoperca australis) and two reproductively isolated genetic lineages of freshwater shrimp (Paratya spp.) in small, geomorphically degraded streams in south eastern Australia. These streams (the Granite Creeks) have been the focus of a recent habitat restoration trial and several studies have examined fish and macroinvertebrate community responses to the experiment. It was the purpose of this study to contribute information about population connectivity in the selected species to complement these community ecology studies. Population connectivity was examined in these species using molecular data (mitochondrial and nuclear genetic data) and natural abundance isotopic signatures of nitrogen and carbon. At the landscape scale, results showed that populations of N. australis and the P. australiensis lineages were isolated among the streams and among sites within streams, and that there was no consistent pattern of isolation-by-distance in genetic data for any species. Thus, classic models of population connectivity, such as the Island Model and Stepping-Stone Model, were not supported by this study. Results indicated that population models that incorporated more complex aspects of stream structure may be more appropriate than these classic models for approximating observed patterns of population connectivity in lotic systems. The Stream Hierarchy Model (SHM) predicts that the hierarchical aspect of stream structure (i.e. stream confluences) have a dominant role in shaping patterns of population connectivity in lotic fauna, whereby populations among streams are more isolated than those within them. Although stream confluences were found to have an important role in population subdivision for the species examined in this study, the expectations of the SHM were met for only N. australis. For the P. australiensis lineages, the influence of topography (i.e. the longitudinal aspect of stream structure) was just as important as stream confluences in isolating local populations. Large-scale determinants of population isolation were thus found to be associated with both the hierarchical and longitudinal aspects of stream structure, and were not well represented by any single theoretical model of population connectivity. At within-stream scales, upland populations tended to be extremely isolated from other populations and had temporally stable genetic signatures. In contrast, lowland populations were connected to other lowland populations within the same stream to a greater degree, although the connections were patchy and a slight signature of temporal instability in the genetic data was evident for one of the P. australiensis lineages. Thus, metapopulation or patchy population models were found to represent connections among lowland populations within the same stream, although they were not appropriate for describing connectivity among upland populations. This finding highlights the importance of the longitudinal aspect of stream structure in shaping ecological patterns in lotic systems, and demonstrates that local patterns of population connectivity can vary over relatively small spatial scales. Overall, the results illustrate that both hierarchical and longitudinal aspects of stream structure can have important roles in isolating populations of stream fauna. They therefore also represent constraints for the ability of aquatic fauna to colonise restored habitat in streams. The corollary of this, however, is that such isolated populations of stream fauna represent appropriate population units at which to target habitat restoration. The hierarchical and longitudinal aspects of stream structure may thus represent 'rules of thumb' or 'landscape filters' that stream restoration ecologists could use to predict likely isolated populations of lotic fauna across the landscape. Such a 'rule of thumb' might be the inclusion of multiple isolated population units in restoration programs, as this strategy is likely to generate the greatest biological response to the restoration at the landscape scale, particularly with respect to intra-specific genetic diversity captured by restoration. At small spatial scales, such as for a single stream or tributary, the longitudinal aspect of stream structure can be an important factor to consider when designing stream habitat restoration programs. In this study, lowland sites were unstable and there were patchy connections among local lowland populations within the same stream, whereas upland populations were isolated at this scale. In contrast, other studies have found that upstream populations of some species can be connected in a patchy fashion in other systems. For such unstable sections of stream, where there are patchy patterns of local population connectivity, the inclusion of multiple restored patches, especially refugial habitat, is likely to produce the greatest biotic response at the patch scale, particularly with respect to demographic responses (such as local colonisation). Multiple restored refugial patches will enable species to persist throughout the stream section during adverse environmental conditions, will allow for variation in local movement patterns and distances between species and between years with contrasting environment conditions (e.g. stream flow), and may harbour different species assemblages and intraspecific genotypes due to stochastic processes (i.e. have functional heterogeneity). The hierarchical and longitudinal aspects of stream structure are thus important determinants of population connectivity at both large and small spatial scales, and have implications for how stream biota will respond to restoration at patch and landscape scales.
36

Relação entre macrofauna, agregação e atributos edáficos em sequência de culturas sob plantio direto / Relationship among macrofauna, aggregation and edaphic attributes in crop sequence under no-tillage

Batista, Itaynara [UNESP] 27 April 2015 (has links) (PDF)
Made available in DSpace on 2016-02-05T18:29:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-04-27. Added 1 bitstream(s) on 2016-02-05T18:33:17Z : No. of bitstreams: 1 000858636.pdf: 1625386 bytes, checksum: f780626b836aa2024118438b39cf66cc (MD5) / O sistema de plantio direto (PD) é apresentado como técnica agrícola que melhora as propriedades químicas, físicas e biológicas do solo. No entanto, ainda permanecem muitas questões quanto ao efeito do tipo e sequência de culturas sobre as interações planta-organismos-solo. O objetivo deste estudo foi investigar o efeito de sequências de culturas em sistema de plantio direto na comunidade da macrofauna edáfica e nas características químicas e físicas dos agregados em duas épocas de avaliação, seca e chuvosa em áreas de domínio morfológico de Mata Atlântica. As hipóteses testadas foram: i) a rotação de culturas com espécies de gramíneas/leguminosas (milho/soja) favorece a formação dos agregados de diferentes tipos morfológicos com diferentes características físicas e químicas, devido à atuação de raízes e a seleção alimentar pela macrofauna do solo; ii) a época de avaliação promove mudanças no ambiente para a formação dos agregados em função da cultura recente e da sazonalidade; iii) os agentes biológicos (macrofauna e raízes) alteram a dinâmica da matéria orgânica associada aos agregados do solo, devido à seleção alimentar pela macrofauna e pela atuação de raízes; iv) a rotação de gramíneas/leguminosas promove maior riqueza de indivíduos, uniformidade da macrofauna edáfica, maior abundância de grupos decompositores de matéria orgânica e engenheiros do ecossistema quando comparada com gramíneas ou com leguminosas, devido a melhoria na disponibilidade de recursos alimentares. O experimento foi realizado sob PD em Jaboticabal - SP, os tratamentos analisados foram: monocultura de soja (leguminosa) no verão e crotalária (leguminosa) na entressafra (S-C), monocultura de milho (gramínea) no verão e milho na entressafra (M-M), rotação soja/milho no verão e uma milho na entressafra (S/M-M) e rotação soja/milho no verão e crotalária ... / The no-tillage system (NT) is presented as an agricultural technique that improves the chemical, physical and biological soil properties. However, many questions still remain as to the effect of the type and sequence of cultures on plantsoil- organisms interactions. The objective of this study was to investigate the effect of crop sequences in no-tillage system in the community of soil macrofauna and chemical and physical characteristics of aggregates in two evaluation periods, dry and wet in areas of morphological domain of Atlantic Forest. The hypotheses tested were: e) crop rotation with species of grass/legumes (corn/soybean) favors the formation of aggregates of different morphological types with different physical and chemical characteristics, due to the action of roots and food selection by soil macrofauna; ii) the evaluation period promotes changes in the environment for the formation of aggregates due to the recent culture and seasonality; iii) biological agents (macrofauna and roots) alter the dynamics of organic matter associated with soil aggregates due to food selection by macrofauna and action of roots; iv) the rotation of grass/legumes promotes greater richness of individuals, uniformity of soil macrofauna, greater abundance of groups decomposers of organic matter and engineers of the ecosystem when compared to grasses or legumes, due to improvement in the availability of food resources. The experiment was conducted under NT in Jaboticabal - SP, the treatments analyzed were: soybean monoculture (legume) in the summer and sun hemp (legume) in the off season (S-SH), corn monoculture (grass) in the summer and corn in the off season (C-C), rotation soybean/corn in the summer and a corn in the off season (S/C-C) and rotation soybean/corn in the summer and sun hemp in the off-season (S/C-SH). The sampling was carried out in August 2012 and March 2013. ...
37

Ocorrência e caracterização molecular de Cryptosporidium spp. em aves selvagens brasileiras

Simões, Daniel Castendo [UNESP] 04 June 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-04Bitstream added on 2014-06-13T18:07:10Z : No. of bitstreams: 1 simoes_dc_me_araca.pdf: 146638 bytes, checksum: 82ece9f69d229b01f099fe04675f2505 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Devido à escassez de informações referentes à ocorrência de Cryptosporidium em aves selvagens no Brasil, este projeto foi realizado visando à detecção de Cryptosporidium em amostras de fezes de várias espécies de aves selvagens da fauna brasileira, por meio da reação em cadeia de polimerase – “nested” (n-PCR). Um total de 488 amostras de 146 espécies de aves selvagens foi coletado em zoológicos, criatórios, Hospitais Veterinários e residências, para extração do DNA genômico de oocistos e realização de n-PCR, visando à amplificação de fragmentos dos genes da subunidade 18S do RNA ribossômico e da actina. Foi observada amplificação para Cryptosporidium em 20 (4,7%) das amostras examinadas. Por meio de sequenciamento dos fragmentos de DNA amplificados foram identificadas duas espécies de Cryptosporidium: C. galli em curiós (Oryzoborus angolensis) e C. baileyi em urubu-de-cabeça-preta (Coragyps atratus). / Due to the paucity of data related to the occurrence of Cryptosporidium in wild birds from Brazilian fauna, this research was accomplished in order to screen fecal samples from various species of wild birds in Brazil for the presence of Cryptosporidium by the use of nested polymerase chain reaction (n-PCR). A total of 488 fecal samples from 146 species of wild birds were collected in Zoos, Veterinary Hospitals, breeder’s facilities and residences. After extraction of genomic DNA from oocysts n-PCR was accomplished for amplification of fragments from 18S subunit of the ribosomal RNA gene and from actin gene. Positive amplification for Cryptosporidium was obtained in 20 (4.09%) samples. Sequencing of amplified fragments allowed the identification of C. galli in lesser-seed finches (Oryzoborus angolensis) and C. baileyi in black vulture (Coragyps atratus).
38

Fauna acompanhante : um universo químico a ser explorado /

Tangerina, Marcelo Marucci Pereira. January 2016 (has links)
Orientador: Wagner Vilegas / Banca: Vanderlan da Silva Bolzani / Banca: Hosana Maria Debonsi / Banca: Luis Octavio Regasini / Banca: Letícia Veras Costa Lotufo / Resumo: A fauna acompanhante da pesca do camarão inclui uma série de invertebrados marinhos que são descartados por não ter valor comercial. A fim de tentar acrescentar algum valor a este material, foi analisada a composição química da estrela-do-mar Luidia senegalensis coletada na costa brasileira como consequência da aplicação da pesca de arrasto. A fim de avaliar sua composição química, foi utilizada uma combinação de extração em fase sólida (SPE) seguida de cromatografia líquida de ultra eficiência acoplada a espectrômetro de massas equipado com fonte de ionização por eletrosptray e analisador ion-trap linear (UPLCESI- IT-MSn). Luidia senegalensis contém asterosaponinas, que são esteroides glicosilados sulfatados contendo cinco e seis unidades de açúcar, além de poliidroxiesteroides. Este estudo mostrou a presença de compostos importantes e potencialmente bioativos em invertebrados associados à fauna acompanhante da pesca do camarão, usando um método rápido e eficiente. Normalmente descartada, a fauna acompanhante contém muitos invertebrados que podem hospedar uma grande variedade de gêneros de bactérias, algumas das quais com potencial de produzir produtos naturais bioativos com aplicações biotecnológicas. Assim, para utilizar um material normalmente descartado, foi explorado o potencial biotecnológico de bactérias cultiváveis de duas espécies de invertebrados abundantes na fauna acompanhante, o gastrópode Olivancillaria urceus e a estrela-do-mar Luidia senegalen... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The by-catch fauna of the shrimp fishery includes a number of marine invertebrates that are discarded because they do not have commercial value. In order to try to add some value to these materials, we analyzed the chemical composition of the starfish Luidia senegalensis collected in the Brazilian coast as a consequence of the trawling fishery method. In order to access their chemical composition, we used a combination of solid phase extraction (SPE) followed by ultra performance liquid chromatography coupled to electrospray ionization ion trap tandem mass spectrometry (UPLC-ESI-IT-MSn). Luidia senegalensis contains asterosaponins, which are sulphated glycosilated steroids, containing five and six sugar moieties, in addition to polyhydroxysteroids. This study helped us to support the presence of important and potentially bioactive compounds in invertebrates associated to the by-catch fauna of the shrimp fishery, using a fast and efficient method. Typically discarded, by-catch contains many invertebrates that may host a great variety of bacterial genera, some of which may produce bioactive natural products with biotechnological applications. Therefore, to utilize by-catch that is usually discarded we explored the biotechnological potential of culturable bacteria of two abundant by-catch invertebrate species, the snail Olivancillaria urceus and the sea star Luidia senegalensis. Sediment from the collection area was also investigated. Utilizing multiple isolation... (Complete abstract click electronic access below) / Doutor
39

Distribuição espacial e estrutura da comunidade de crustáceos de águas intersticiais de um igarapé amazônico e um riacho da mata atlântica / Spatial distribution and structure of interstitial water crustacean assemblages in an Amazonian stream and an Atlantic forest stream

Luciana Paes de Andrade 03 May 2007 (has links)
As comunidades da fauna de copépodes de águas intersticiais da zona hiporrêica de um igarapé da Amazônia Central e de um rio da mata atlântica da região Sudeste do Brasil são comparadas quanto à composição, diversidade, e distribuição dos organismos. A relação das espécies identificadas com os fatores abióticos é analisada, com o objetivo de se estabelecer quais são os fatores determinantes para a distribuição das mesmas. Os fatores abióticos mensurados são: temperatura, pH, oxigênio dissolvido e granulometria do sedimento. Na areia grossa, há dominância de copepoditos e do gênero Forficatocaris (uma espécie para a mata atlântica e duas novas para a Amazônia). Essas três espécies e os copepoditos exploram o mesmo tipo de micro-hábitat no substrato. Quando a areia média é o substrato predominante, há o aumento na presença dos outros gêneros, como Potamocaris (uma espécie para a mata atlântica e uma nova espécie para a Amazônia) e Parastenocaris (mata atlântica), além do declínio no número de copepoditos. Há uma relação direta entre a temperatura e a distribuição dos microcrustáceos, ocorrendo o predomínio destes animais em temperaturas mais baixas. Há diferenças significativas dos valores de pH quando comparadas localidades distintas (Amazônia e mata atlântica); no entanto, quando comparadas as estações seca e chuvosa de um mesmo local, essa diferença não aparece. Sugere-se que o pH influencie na composição das espécies, e não em sua distribuição. Há um número similar de espécies ocupando os dois ambientes e um padrão de distribuição da fauna hiporrêica. Estas semelhanças apontam para a existência de padrões na estrutura e funcionamento destas comunidades naturais de microcrustáceos intersticiais, moldadas por pressões seletivas parecidas. / The assemblages of the copepod fauna from interstitial waters in the hyporheic zones from a stream in Central Amazon and a stream in the Atlantic rainforest of southeastern Brazil were compared in terms of composition, diversity and organism distribution. The relation of the identified species with abiotic factors was analyzed, aiming at establishing which factors were determinant for their distribution. The abiotic factors analyzed were: temperature, pH, dissolved oxygen, and sediment granulometry. In thick sand, there is predominance of copepodites and of the genus Forficatocaris (one species found in the Atlantic rainforest and two new species in the Amazon). These three species of Forficatocaris and the copepodites explore the same kind of microhabitat in the sediment. When medium size of sand grains prevail, there is an increase in the presence of other genera, such as Potamocaris (one species for the Atlantic rainforest and one new species for the Amazon) and Parastenocaris (Atlantic rainforest), besides a decline in number of copepodites. There is a direct ratio between the temperature and the distribution of microcrustaceans, with a predominance of these invertebrates in lower temperatures. There are significant differences in pH values when both localities (Amazon and Atlantic rainforest) are compared; however, comparisons between seasons (lower rainfall versus rainy periods) in a same location did not yield differences. It is suggested that the pH influences species composition, but not species distribution. There is a similar number of species inhabiting both environments and a distribution pattern for the hyporheic fauna. These similarities point at the existence of patterns in the structure and behavior in these natural communities of interstitial microcrustaceans, molded by similar selective pressures.
40

Faunística e distribuição geográfica de hidróides bentônicos (Cnidaria, Hydrozoa) do sudoeste do Atlântico / Faunistic and geographic distribution of benthic hydroids (Cnidaria, Hydrozoa) from southwestern Atlantic

Thaís Pires Miranda 07 December 2009 (has links)
O aprofundamento de estudos faunísticos e taxonômicos é essencial para a inferência de áreas de distribuição geográfica e, conseqüentemente, de áreas de endemismo. Estes estudos são incipientes para o ambiente marinho, incluindo o sudoeste do Atlântico, particularmente em relação aos cnidários. Os principais objetivos deste estudo foram (1) levantar a fauna de hidróides bentônicos da região entre Cabo Frio (Brasil) e Terra do Fogo (Argentina) e (2) inferir a distribuição geográfica das espécies levantadas, buscando uma eventual caracterização de áreas de endemismo. No total, 181 morfoespécies de hidróides foram registradas, sendo que destas, 10 são registros novos para a região (Aglaophenia trifida, Antennella secundaria, Cryptolarella abyssicola, Filellum contortum, Lafoea coalescens, Lovenella gracilis, Macrorhynchia grandis, ?Nemertesia ciliata, Sertullarella leiocarpa e Zygophylax sibogae) e 9 são espécies endêmicas (Corymorpha januarii, Ectopleura obypa, Eudendrium caraiuru, Hydractinia uniformis, Lytocarpia canepa, Parascyphus repens, Plumularia insignis, Ralpharia sanctisebastiani, Symplectoscyphus magellanicus) para a área. A riqueza de espécies teve uma pequena diminuição com o aumento da latitude e diminuiu drasticamente em águas mais profundas (abaixo das isóbatas de 100 e 1000m). A análise de PCA demonstrou que os substratos Algae, Hydrozoa, Mollusca, Porifera e Rocha apresentaram os maiores números de ocorrência de morfoespécies de hidróides. A análise de cluster resultou na delimitação de três grupos de fauna: (1) brasileiro costeiro, (2) uruguaio-argentino e (3) oceânico contínuo por toda a área amostrada. Em relação às áreas de endemismo, as análises com o NDM-VNDM resultaram em duas principais áreas endêmicas costeiras para o litoral do Brasil (entre 22-24°S 43-46°W e entre 26-29°S 48-49°W), sendo que a metodologia PAE resultou em quatro áreas endêmicas para a região de estudo: (1) áreas costeiras contínuas para o Brasil ou Argentina; (2) áreas costeiras e contínuas entre o Brasil e Argentina; (3) áreas oceânicas contínuas entre Cabo Frio e Terra do Fogo; (4) áreas restritas à região do rio da Prata. Nossos resultados revelaram que a correspondência entre as faunas de profundidade brasileira e de regiões mais rasas do litoral argentino pode estar relacionada com o regime de frentes oceânicas atuantes no sudoeste do Atlântico. Além disso, análises incluindo exclusivamente espécies de hidróides que produzem medusa em seus ciclos de vida resultaram em áreas de endemismo mais restritas à costa em relação às espécies que formam somente gonóforos fixos. Estes resultados contradizem o paradigma clássico que associa a presença de medusa com a alta capacidade dispersiva das espécies. / Increasing on faunistic and taxonomic knowledge is essential for reliable inferences on the geographical distribution and, consequently, on areas of endemism. This knowledge is incipient for the marine realm, including southwestern Atlantic, and particularly poor for cnidarians. The main goal of this study was (1) to survey the fauna of benthic hydroids from the region between Cabo Frio (Brasil) and Terra do Fogo (Argentina), and (2) to infer the geographic distribution of the surveyed species, aiming to propose areas of endemism. A total of 181 morphospecies of hydroids was recorded, 10 species are new records (Aglaophenia trifida, Antennella secundaria, Cryptolarella abyssicola, Filellum contortum, Lafoea coalescens, Lovenella gracilis, Macrorhynchia grandis, ?Nemertesia ciliata, Sertullarella leiocarpa e Zygophylax sibogae) and 9 are endemic species (Corymorpha januarii, Ectopleura obypa, Eudendrium caraiuru, Hydractinia uniformis, Lytocarpia canepa, Parascyphus repens, Plumularia insignis, Ralpharia sanctisebastiani, Symplectoscyphus magellanicus) for the area. Species richness slightly decreases along higher latitudes and along deeper waters (below 100 and 1000m isobaths). A PCA analyses has demonstrated that the substrata, Algae, Hydrozoa, Mollusca, Porifera and Rock showed a higher number of morphospecies of hydroids. Cluster analysis resulted in three faunistic groups: (1) Brazilian-coastal, (2) Uruguayan-Argentinean and (3) and oceanic group continuous along the entire surveyed area. Concerning areas of endemism, NDM-VNDM analyses resulted in two main coastal areas of endemism on the Brazilian coast (between 22-24°S 43-46°W and between 26-29°S 48- 49°W), and PAE resulted in four areas of endemism for the studied area: (1) coastal area in Brazil or Argentina; (2) a coastal and continuous area along Brazil and Argentina; (3) an oceanic and continuous area; (4) a Rio de La Plata area. Our results have shown that faunal affinities between Brazilian deep fauna and Argentinean shallow water fauna might be related to the marine fronts present in the southwestern Atlantic. Moreover, analyses exclusively including hydroid species with medusa in the life cycle resulted in more limited areas of endemism closer to the coast than those analyses exclusively including hydroids species with fixed gonophores. These results contradict the classical paradigm associating the presence of medusa and higher dispersive capabilities of the species.

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