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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.
171

Historia natural e comportamento social de Anelosimus Jabaquara e Anelosimus Dubiosus (Araneae : Theridiidae)

Marques, Evelyn Sodre de Alckmin 05 April 1991 (has links)
Orientador : João Vasconcellos-Neto / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-13T22:42:53Z (GMT). No. of bitstreams: 1 Marques_EvelynSodredeAlckmin_M.pdf: 3956699 bytes, checksum: 6ade91ce16e7b521cf1c6ae4754a6f4b (MD5) Previous issue date: 1991 / Resumo: Não informado / Abstract: Not informed. / Mestrado / Ecologia / Mestre em Ciências Biológicas
172

Ecologia e pesca da piramutaba (Brachyplatystoma vaillantii)

Barthem, Ronaldo Borges 18 May 1990 (has links)
Orientador :Miguel Petrere Jr / Tese (doutorado) - Universidade Estadualde Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-13T23:02:30Z (GMT). No. of bitstreams: 1 Barthem_RonaldoBorges_D.pdf: 12862461 bytes, checksum: 6ed0a725d3a343264fcfd5b36565e332 (MD5) Previous issue date: 1990 / Resumo: A piramutaba (Brachyplatystoma vaillantii),Pimelodidae) é a espécie de peixe mais importante dentre aquelas que são exportadas da Amazônia e foi a terceira em ordem de importância dos que foram exportadas do Brasil em 1987. Sua pesca ocorre principalmente no estuário e canal principal do rio Amazonas e é realizada por duas frotas pesqueiras distintas: artesanal e industrial. A pesca artesanal emprega a rede de emalhar à deriva com malhas de 14.-22 cm; é responsável por cerca de 30% do total que é desembarcado; e comercializa toda a sua produção nos mercados de pescados da região. Esse método captura piramutabas tanto no estuário quanto no canal l principal do rio Amazonas, de comprimento forcal acima de 44,9 cm a idade acima de 3,75 anos. A pesca industrial emprega a rede de arrasto de porta, puxada por uma parelha de barcos; é responsável por cerca de 70% do total que é desembarcado; e comercializa a sua produção no mercado internacional. Esse método captura piramutabas somente no estuário amazônico, de comprimento forcal acima de 18,1 cm e de idade acima de 0,95 anos, e sua. atuação resulta na rejeição de até 56% do que capturam. A relação entre rendimento por recruta' (Y/R) e mortalidade por pesca (F) foi estimada para ambas as frotas. ... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: The catfish piramutaba (Bracyplatystoma vaillantii, Pimelodidae) is the most important export fish of the Amazon basin and estuary and was the third ranked export fish of Brazil in 1987. There are two kind of fisheries exploiting this species: traditional and industrial. The traditional fishery use gillnet with mesh 14- 22 cm. It is responsible for about 30% of landed catch, which is sold in the regionional market. This method catches fish in the Amazon river ando estuary with minimum fork length 44.9 cm and age 3.75 y. The industrial fishery uses trawl-seines with two trawlers. It is responsible for about 70% of all landed catch, which is sold on the international market. This method catches fish only in the Amazon river with minimum fork length 18.1 cm and age of 0.95 Y and result in discarding up to 56% of the catch. The relation between yield per recruit (VIR) anel fishery mortality (F) was estimated forboth fisheries. The total mortality (Z) was 1.18 and 0.94 years-1, in 1984 and 1985, based on the sample landed by the traditional fishery. The natural mortality (M) was 0.5 years-1, indirectly estimated. ... Note: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Ecologia / Doutor em Ciências Biológicas
173

Analise floristica e ordenação de especies arboreas da mata Atlantica atraves de dados binarios

Siqueira, Marinez Ferreira de 22 December 1994 (has links)
Orientador: Fernado Roberto Martins / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-19T23:25:33Z (GMT). No. of bitstreams: 1 Siqueira_MarinezFerreirade_M.pdf: 10748180 bytes, checksum: 83af159d34ce6f4d7dfb07c5852161ab (MD5) Previous issue date: 1994 / Resumo: A Mata Atlântica, apesar de ser um dos ecossistemas mais diversificados do Brasil é, ainda pouco conhecido floristicamente. Existe muita divergência quanto a sua localização e seus limites. O objetivo principal deste trabalho é tentar encontrar algum padrão no componente arbóreo da vegetação que possa caracteriza-la como um bloco homogêneo ou como um conjunto de blocos floristicamente distintos. Foi considerada Mata Atlântica a formação florestal ocorrentes nas serras do Mar, da Mantiqueira e Geral, as matas do sul da Bahia e norte do Espírito Santo e fragmentos de vegetação no Nordeste. Para o estado de São Paulo. considerou-se também parte do Planalto Atlântico. A partir de um levantamento bibliográfico sobre a vegetação de Mata Atlântica, selecionaram-se 63 levantamentos do componente arbóreo presente nos estados de Alagoas, Bahia, Espírito Santo. Rio de Janeiro. São Paulo, Paraná. Santa Catarina e Rio Grande do Sul. Com base nos levantamentos, foi montado um banco de dados binários das espécies arbóreas ocorrentes nessas regiões. totalizando 1706 espécies. reduzidas a 1338 devido a correção e atualização dos táxons pela literatura. Foram utilizados os índices de Jaccard e de pareamento simples para medir o grau de semelhança entre as amostras. Os valores de similaridade foram submetidos a uma análise de aglomerados. As áreas foram ordenadas pelo PCO e as espécies pelo Twinspan. Cerca de 0.1% das espécies. 6% dos gêneros e 38% das famílias ocorreram em mais da metade das 63 localidades utilizadas. o que mostra a heterogeneidade da vegetação em questão. A Região Sudeste apresentou a maior riqueza de espécies (85%), seguido pelo Nordeste (22%) e o Sul com 18%. A Região Nordeste apresentou a maior concentração de táxons sem identificação a nível de espécies, gêneros e famílias. Foram identificados, de uma forma geral, dois grandes blocos floristicos na Mata Atlântica. Um presente na Região Nordeste e outro na Região Sudeste/Sul. O bloco do Nordeste divide-se em dois, um presente no estado de Alagoas e outro no estado da Bahia. A Região Sudeste/Sul divide-se, de uma forma bem menos nítida, em cinco grupos, dois no estado de São Paulo e três na Região Sul. No estado de São Paulo, os dois blocos observados fazem uma separação nítida entre as floras próximas ao litoral (ocorrentes em planície ou em serras) e as matas do interior (ocorrentes em planalto ou em serras). As áreas pertencentes ao estado do Espírito Santo apareceram ora associadas ao bloco do Nordeste, ora ao bloco do Sudeste/Sul, ou mesmo totalmente isoladas dependendo do método utilizado. O que sugere que seja nesta região a área de sobreposição das distribuições geográficas dos dois grandes blocos floristicos, ou que seja um grande centro de diversidade de espécies da Mata Atlântica / Abstract: The floristic of the Atlantic Forest is not well know, despite being one of the most diversified ecosystems in Brazil. There is a lot of disagreement regarding it's location and boundaries. The main objective of this work is to determine a pattern on the arboreal vegetation that classifies it as a homogeneous block or a set of blocks with distinct floristics. The Atlantic Forest was considered as being the Forestry present in the mountain ridge of Mantiqueira, of Mar and Geral, plus the forests at the south of Bahia State and north of Espirito Santo State, and vegetation fragments on the northeast of Brazil. In the São Paulo State, it was included the Atlantic Plateau. Beginning with a bibliographic survey about the Atlantic Rain Forest vegetation, 63 arboreal surveys were selected in the States of Alagoas, Bahia, Espírito Santo, Rio de Janeiro, São Paulo, Parana, Santa Catarina and Rio Grande do Sul. Based on these surveys a database was structured with binary data on the arboreal species occurring in these regions, adding 1706 species, reduced to 1338 due to taxon actualization. The Jaccard Index and Simple Matching were utilized to access the similarity between samples. The similarity values were submitted to cluster analysis. The areas were ordered by PCO and the Twinspan species. About 0,1% of the species, 6% of the genera and 38% of the families occurred in more than 50% of the localities studied, which shows the heterogeneity of the vegetation. The Southeast Region presented the greatest concentration of species (85%), followed by the Northeast Region (22%) and the South Region (18%). The Northeast Region presented the greatest concentration of taxa without identification at species, genera and family leveI. Two floristic blocks were individualized in the Atlantic Forest: one in the Northeast Region and the other in the southeast and South Region of Brasil. The northeast block is divided in two parts, one in the State of Alagoas and another in the State of Bahia. The Southeast South Block is divided, less distinctly, in five parts: two in the State of São and three in the South Region of Brasil. In the State of São Paulo, the two observed blocks separated the coast flora (occurring in plains and mountain ridges) and the interior forests (occurring in plateaus and mountain ridges). The areas in the State of Espírito Santo are associated with the northeast block, the southeast block or isolated, depending in the methodology utilized, suggesting that the region is the overlap area of the geographic distribution of the two great floristic blocks, or a biodiversity center of Atlantic Forest species / Mestrado / Ecologia / Mestre em Ciências Biológicas
174

Spatial and temporal variability and ecological processes in the epibenthic assemblages of the northern Adriatic Sea

Fava, Federica <1978> 09 May 2011 (has links)
Several coralligenous reefs occur in the soft bottoms of the northern Adriatic continental shelf. Mediterranean coralligenous habitats are characterised by high species diversity and are intrinsically valuable for their biological diversity and for the ecological processes they support. The conservation and management of these habitats require quantifying spatial and temporal variability of their benthic assemblages. This PhD thesis aims to give a relevant contribution to the knowledge of the structure and dynamics of the epibenthic assemblages on the coralligenous subtidal reefs occurring in the northern Adriatic Sea. The epibenthic assemblages showed a spatial variation larger compared to temporal changes, with a temporal persistence of reef-forming organisms. Assemblages spatial heterogeneity has been related to morphological features and geographical location of the reefs, together with variation in the hydrological conditions. Manipulative experiments help to understand the ecological processes structuring the benthic assemblages and maintaining their diversity. In this regards a short and long term experiment on colonization patterns of artificial substrata over a 3-year period has been performed in three reefs, corresponding to the three main types of assemblages detected in the previous study. The first colonisers, largely depending by the different larval supply, played a key role in determining the heterogeneity of the assemblages in the early stage of colonisation. Lateral invasion, from the surrounding assemblages, was the driver in structuring the mature assemblages. These complex colonisation dynamics explained the high heterogeneity of the assemblages dwelling on the northern Adriatic biogenic reefs. The buildup of these coralligenous reefs mainly depends by the bioconstruction-erosion processes that has been analysed through a field experiment. Bioconstruction, largely due to serpulid polychaetes, prevailed on erosion processes and occurred at similar rates in all sites. Similarly, the total energy contents in the benthic communities do not differ among sites, despite being provided by different species. Therefore, we can hypothesise that both bioconstruction processes and energetic storage may be limited by the availability of resources. Finally the major contribution of the zoobenthos compared to the phytobenthos to the total energetic content of assemblages suggests that the energy flow in these benthic habitats is primarily supported by planktonic food web trough the filter feeding invertebrates.
175

Genetic and Morphological Features of Patella Caerulea and Patella Rustica across Mediterranean Marine Protected Areas

Marti Puig, Patricia <1985> January 1900 (has links)
Marine Protected Areas (MPAs) were initially created to protect the living, non-living, cultural and/or historical values from human activities. The Convention on Biological Diversity (CBD; Earth Summit in Rio de Janeiro on 5 June 1992) has set a target of protecting 10% of the coastal and marine areas by 2020, which has led to a rapid increase in the creation of MPAs worldwide. Within this context, there is a growing concern regarding the number of efficient MPAs. One of the main issues is that biological or ecological features of marine species as well as ecosystem processes are not taken into account in MPA design. Deciding criteria for species management requires considerable information collected from a number of sources, including morphometric data, genetic data and distributional data. Morphometric tools are useful to study species taxonomy, or to provide information about the morphological variability, size and growth of the species, which is essential for MPA monitoring. Genetic tools can be use to resolve species taxonomy or population structure, allowing to estimate genetic diversity and connectivity of populations at different temporal and spatial scales. Both morphometric and genetic data used in combination provide a powerful tool that should be considered in MPA assessment. However, the accurate interpretation and the integration of this information into marine spatial planning is specially challenging. The aim of this PhD thesis was to develop a protocol for monitoring Marine Protected Areas by studying the morphology and genetics of two closely limpet species (Patella rustica and Patella caerulea) across MPAs in the Western Mediterranean sea. Overall, the results of this thesis provides support the inclusion of the morphological and genetic tools into management plans, and in the guidelines for the monitoring to improve and/or maintain MPA health and effectiveness.
176

Effects of Local and Global Stressors on the Status and Future Persistence of Intertidal Canopy-Forming Algae

Mancuso, Francesco Paolo <1982> January 1900 (has links)
Canopy-forming seaweeds are worldwide disappearing due to the combined effects of human activities and climate instabilities. Identifying the type and strength of interactions between multiple anthropogenic and natural stressors can help setting achievable management targets for degraded ecosystems and support ecological resilience through local actions. This thesis aimed to understand how algal forests change from extensive to degraded, and what factors can enhance the ability of forests to withstand or recover from stressors. I contributed to a systematic review to infer potential important synergistic stressors interactions driving the loss of canopy-forming seaweeds at a global level. We found that management of excess nutrient levels would provide the greatest opportunity for preventing the shift from canopy to mat-forming algae, because of the higher prevalence of synergistic interactions between nutrient enrichment with other local and global stressors. Then, I focused my attention on fucoid algae of the genus Cystoseira that are the most typical canopy-forming seaweeds in the Mediterranean Sea. I explored which environmental and anthropogenic factors can explain the current status of the intertidal Cystoseira populations. I found that coastal urbanization and nutrient concentration were the factors most related to the status of Cystoseira. Finally, I carried out a series of manipulative field experiments to explore the effects of nutrient enrichment and heat-wave events on intertidal C. compressa. The results showed that C. compressa is sensitive to heat-wave events and that local biodiversity and thermal history of the alga seem to play a role reducing or increasing respectively the impact of such extreme events. I also characterised the epiphytic bacteria associated to the surface of C. compressa and showed their potential influence on the responses of C. compressa to environmental stressors.
177

Analysis of cumulative effects of multiple stressors on saltmarshes and consideration of management options

Wong, Joanne Xiao Wen <1983> 29 June 2015 (has links)
Natural systems face pressures exerted by natural physical-chemical forcings and a myriad of co-occurring human stressors that may interact to cause larger than expected effects, thereby presenting a challenge to ecosystem management. This thesis aimed to develop new information that can contribute to reduce the existing knowledge gaps hampering the holistic management of multiple stressors. I undertook a review of the state-of-the-art methods to detect, quantify and predict stressor interactions, identifying techniques that could be applied in this thesis research. Then, I conducted a systematic review of saltmarsh multiple stressor studies in conjunction with a multiple stressor mapping exercise for the study system in order to infer potential important synergistic stressor interactions. This analysis identified key stressors that are affecting the study system, but also pointed to data gaps in terms of driver and pressure data and raised issues for potentially overlooked stressors. Using field mesocosms, I explored how a local stressor (nutrient availability) affects the responses of saltmarsh vegetation to a global stressor (increased inundation) in different soil types. Results indicate that saltmarsh vegetation would be more drastically affected by increased inundation in low than in medium organic matter soils, and especially in estuaries already under high nutrient availability. In another field experiment, I examined the challenges of managing co-occurring and potentially interacting local stressors on saltmarsh vegetation: recreational trampling and smothering by deposition of excess macroalgal wrack due to high nutrient loads. Trampling and wrack prevention had interacting effects, causing non-linear responses of the vegetation to simulated management of these stressors, such that vegetation recovered only in those treatments simulating the combined prevention of both stressors. During this research I detected, using molecular genetic methods, a widespread presence of S. anglica (and to a lesser extent S. townsendii), two previously unrecorded non-native Spartinas in the study areas.
178

Towards an Ecosystem Approach to Fisheries for Nephrops Norvegicus and Meluccius Merluccius Inhabiting the Central Adriatic Sea

Angelini, Silvia <1986> January 1900 (has links)
This study presents the development of a Model of Intermediate Complexity for Ecosystem assessments (MICE) for testing management scenarios for the stock of European hake (Merluccius merluccius) and Norway lobster (Nephrops norvegicus) inhabiting the Central Adriatic Sea. These two species represent the target species, as well as the predators, of this study. They are mainly fished by Italian and Croatian bottom trawl fishery, accounting for both the highest landings and commercial value among demersal species in the area. The specific circulation of the Adriatic Sea is responsible for strong nutrient recycling processes within this area, resulting in a rich fishing ground extensively exploited by Italian and Croatian fishing vessels, make it an interesting case study for the development of an Ecosystem Approach to Fisheries (EAF). Here, an EAF was developed using the MICE approach, since it is well adapted to test specific management questions, as required by this study. The MICE was developed in a step-wise manner. Firstly, single-species stock assessments for both the target species were pursued, allowing the evaluation of the state of these resources and permitting the production of the input values to be included within the MICE. Secondly, the diet of the target species were examined and prey items portioned in four groups; consumption of each prey group by each predator was modelled using a Holling Type II functional response. Finally, predator and prey dynamics were linked within the MICE model, using a modified biomass dynamic model to project them into the future and testing different management strategies. The best management scenario resulted to be the protection of adults, which produced the most beneficial results for both predators and prey groups.
179

Efeitos do canto de anúncio e do tamanho corporal no espaçamento entre machos em agregações de Dendropsophus nanus (Anura, Hylidae)/

Sousa, Verônica Thiemi Tsutae de. January 2012 (has links)
Orientador: Christopher Gordon Murphy / Coorientador: Denise de Cerqueira Rossa Feres / Banca: Cynthia Peralta de Almeida / Banca: Itamar Alves Martins / Resumo: Em anuros, a manutenção de espaçamento entre machos constitui uma importante adaptação às agregações reprodutivas, minimizando o mascaramento auditivo e aumentando o sucesso reprodutivo dos machos emissores de vocalização. O canto de anúncio transmite informações com o potencial de influenciar o estabelecimento e a manutenção de espaçamento entre machos, como a habilidade de luta e a localização dos machos. Avaliamos o espaçamento entre machos de Dendropsophus nanus (Anura, Hylidae), que emitem canto de anúncio formado por duas notas: as introdutórias (notas A) e as secundárias (notas B). Testamos três hipóteses: 1) o espaçamento entre machos é influenciado por um ou mais parâmetros do canto de anúncio; 2) o canto de anúncio transmite informações a respeito do tamanho corporal dos machos; 3) o espaçamento entre machos é mediado por notas introdutórias. Machos de D. nanus utilizam ambas as notas para advertir seu tamanho corporal e sua localização no habitat reprodutivo. No entanto, somente as notas A transmitem ambas as informações por meio dos mesmos parâmetros acústicos, relativos à estrutura da nota. As notas B transmitem as informações relativas ao tamanho corporal pela taxa de repetição de notas e de pulsos, enquanto o espaçamento foi influenciado pelo número e duração dos pulsos. Além disso, o espaçamento entre machos foi maior quando mediado por notas A do que por notas B. Assim, as notas A informam a coespecíficos a habilidade competitiva do macho emissor da vocalização, enquanto as notas B advertem a qualidade reprodutiva dos machos às fêmeas / Abstract: In anurans, the maintenance of spacing between males is an important adaptation to the chorus, reducing auditory masking and maximizing the transmission of the calls and males' reproductive success. Advertisement call conveys information with the potential to influence the establishment and maintenance of intermale spacing, like competitive ability and location of males. We evaluate intermale spacing in natural aggregation of Dendropsophus nanus (Anura, Hylidae), whose advertisement call is constituted by two notes: the introductory (type A notes) and the secondary (type B notes). We tested three hypotheses: 1) intermale spacing is influenced by one or more parameters of the advertisement call; 2) the advertisement call contains information about male body size; 3) intermale spacing is mediated by introductory notes. Males of D. nanus use both notes to advertise their body size and their location in the reproductive habitat to other conspecifics. However, only A notes convey both kinds of information through the same acoustic parameters, which are related to note structure. Type B notes advertise body size through note and pulses repetition rate, while spacing is associated to the number and duration of pulses. Furthermore, intermale spacing was greater when mediated by A notes than when mediated by B notes. Therefore, A notes advertise mainly a male's competitive ability in male-male interactions, while B notes appear to advertise the males' reproductive quality to females / Mestre
180

Associações de foraminíferos e tecamebas da foz do Rio Itajaí-Açú, SC, relacionadas com os subambientes de deposição. / Not available.

Santos, Rosa Penha dos 09 September 1987 (has links)
A presente dissertação trata de um levantamento da distribuição de foraminíferos e tecamebas atuais no baixo rio Itajaí-Açú, Estado de Santa Catarina, até a região marinha sob a influência deste rio, com o objetivo de se estabelecer um padrão de distribuição destes organismos e sua possível utilização na interpretação da hidrodinâmica das correntes fluviais e costeiras, principalmente as de maré. Foi possível, deste modo, distinguir os seguintes subambientes: a) marinho; b) estuarino; c) Saco de Fazenda e molhes fluviais; d) fluvial. No subambiente fluvial foi possível distinguir áreas de maior influência marinha e áreas de menor influência marinha, possivelmente ligadas às direções das correntes fluviais de maré. A distribuição das associações dos organismos em pauta foi comparada com a distribuição nas regiões flúvio-marinhas da foz do rio Doce e do Sistema Mariricu - S. Mateus, no Estado do Espírito Santo. Ressaltou-se desta comparação que os três sistemas flúvio-marinhos são diferentes entre si, diferenças estas explicadas pelo maior ou menor grau de penetração das correntes de maré rio adentro. / The purpose of this research was to establish the pattern bof distribution of living foraminifers and thecamoebians along the lower Itajaí-Açu river and adjacent ocean in the State of Santa Catarina, Brazil, and to interpret this pattern in the light of the interplay of river and tidal currents. The distribution of these organisms allowed the recognition of the following subenvironments: a) marine; b) estuarine; c) \"Saco da Fazenda\" and \"molhes\"; d) fluviatile. Areas of marked marine influence and areas of marked river influence were detected within the fluviatile subenvironment, of river and tidal currents reflecting the interplay. Comparisions with similar mixed fluviatile and marine patterns of these organisms in the State of Espírito Santo, Brazil, at the mouths of the Doce River and the Mariricu - S. Mateus river system revealed significant differences between these river systems as the result of differing penetration of marine waters along the river channels.

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