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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.
51

Leis autorizativas para supressão de manguezais e as consequências socioambientais para o estado de Pernambuco

TAVARES, Patrícia Ferreira 05 March 2015 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-10-03T18:27:28Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) dissertação Patrícia Tavares - FINAL (Reparado).pdf: 1372192 bytes, checksum: f1841220d38eebee90f4380313bf2378 (MD5) / Made available in DSpace on 2016-10-03T18:27:28Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) dissertação Patrícia Tavares - FINAL (Reparado).pdf: 1372192 bytes, checksum: f1841220d38eebee90f4380313bf2378 (MD5) Previous issue date: 2015-03-05 / O presente trabalho buscou saber os prejuízos socioambientais decorrentes da eliminação do ecossistema manguezal, e se o Estado de Pernambuco está cumprindo o disposto na legislação ambiental quanto ao andamento do procedimento administrativo para supressão de vegetação considerada de Preservação Permanente. Como hipóteses, a pesquisadora elencou duas: considerando todos os benefícios decorrentes das funções ecológicas do ecossistema manguezal, o estado de Pernambuco perde drasticamente em termos de biodiversidade, que consequentemente desencadeia prejuízos socioambientais; e o Estado de Pernambuco incorre em ilegalidade e inconstitucionalidade na emissão de leis autorizativas para supressão de manguezal, descumprindo ainda princípios do direito ambiental. De acordo com os objetivos da pesquisa, realizou-se uma pesquisa documental/bibliográfica, quanto à legislação protetiva, à administração pública e aos procedimentos administrativos, inclusive ao nível nacional, para autorização de interferência no ecossistema e uma atualização das leis ordinárias com relação à autorização de supressão de áreas de manguezal no site da Assembleia Legislativa do Estado de Pernambuco. Tendo em vista que os pescadores, considerados comunidade tradicional, estão intrinsecamente ligados ao manguezal, foram realizadas 22 entrevistas com pescadores da colônia Z – 8, situada no município de Cabo de Santo Agostinho e 23 entrevistas com pescadoras da colônia Z-12, situada no município de Ipojuca. A atualização das leis autorizativas culminou com o resultado de 601,00 ha de manguezal autorizados a suprimir, o que desencadeou um verdadeiro desastre socioambiental, a partir da violação dos princípios ambientais e as disposições legais referentes. / The present study sought to know the social and environmental losses arising from the removal of mangrove swamp, and the state of Pernambuco is meeting the requirements of environmental legislation when the progress of the administrative procedure for removal of considered Permanent Preservation vegetation. As hypotheses, the researcher has listed two: considering all the benefits of the ecological functions of the mangrove ecosystem, the State of Pernambuco dramatically lose in terms of biodiversity, which in turn sets off sociambientais losses; and the State of Pernambuco incurs illegality and unconstitutionality in issuing authorization laws for suppression of mangrove swamp, still not complying with principles of environmental law. According to the research objectives, there was a documentary /bibliography research, about the protective legislation, public administration and administrative procedures, including the national level to permit interference in the ecosystem and an update to the ordinary laws regarding the authorization of removal of mangrove areas in Pernambuco State Legislative Assembly website. Having in mind that the traditional community - fishermen who are intrinsically linked to the mangrove swamp, there were 22 interviews with fishermen from the Z - 8 colony, located in the municipality of Cabo de Santo Agostinho and 23 interviews with fishers from the Z -12 colony, in the municipality of Ipojuca. Updating authorization acts culminated with the result of 601.00 ha of mangrove swamp allowed to suppress, which triggered a socioenvironmental disaster from the violation of environmental principles and legal provisions concerning.
52

Evaluation of mechanical site preparation and Oust XP treatments on survival and growth of three oak species planted on retired agricultural areas and a case study of a mixed Nuttall oak-green ash planting

Self, Andrew Brady 30 April 2011 (has links)
Bare-root Nuttall oak, Shumard oak, and swamp chestnut oak seedlings were planted on former agricultural fields in Mississippi to evaluate growth and survival following treatment by different combinations of mechanical site preparation and pre-emergent Oust XP® applications. Mechanical treatments included: (1) controls, (2) subsoiling treatment, (3) bedding treatment, and (4) combination plowing. Pre-emergent Oust XP® treatments included: (1) one-year Oust XP® applications and (2) two-year Oust XP® applications. Evaluations and measurements were performed over the course of three years. Results within this dissertation should be considered in the context of high quality former agricultural sites with silt loam soils. Seedling height and GLD increased each growing season. Height and GLD of seedlings were greater in bedded and combination plowed areas compared to control and subsoiled areas. Height and GLD were not different by Oust XP® application. However, seedling survival in two-year Oust XP® application areas was reduced compared to one-year Oust XP® application areas. Nuttall oak seedlings planted in bedded and combination plowed areas exhibited greater stem biomass compared to those planted in control or subsoiled areas. Seedlings planted in two-year Oust XP® areas exhibited greater stem and root biomass compared to those planted in areas receiving the one-year treatment. Better growth and biomass production in bedded and combination plowed areas would promote their use for site preparation on similar sites. While survival was lower in two-year Oust XP® treatment areas compared to one-year treatment areas, the difference would not warrant change in management strategy. Additionally, woody biomass was much greater in two-year Oust XP® areas. Thus, if cost is not prohibitive, treatment with two years of Oust XP® is recommended. The objective of the mixed species study was to establish baseline growth and survival data for mixed Nuttall oak and green ash plantations on former agricultural areas. Height and GLD for both species increased each growing season. Third-year survival was excellent at 96.0 percent. In conclusion, the mixture performed satisfactorily. Growth and survival were excellent, which indicates this mixture would be useful in afforesting similar former agriculture sites.
53

Some Palynological Applications of Multivariate Statistics

Adam, David Peter January 1970 (has links)
Palynology involves the study of past climatic and environmental changes through changes in the relative frequencies of different pollen types through time. Several multivariate statistical methods are suggested which can help in the description of patterns within pollen data. These techniques are based on comparisons between samples. Samples were compared using the product-moment correlation coefficient computed from data which had been subjected to a centering transformation. The methods are described using a geometric model. If there are m samples and n pollen types, then the data can be regarded as a set of m points in an n-dimensional space. Cluster analysis produces a dendrograph or clustering tree in which samples are grouped with other samples on the basis of their similarity to each other. Principal component analysis produces a set of variates which are linear combinations of the pollen samples, are uncorrelated with each other, and do the best job of describing the data using a minimum number of dimensions. This method is useful in reducing the dimensionality of data sets. Varimax rotation acts on a subset of the principal components to make them easier to interpret. Discriminant analysis is used to find the best way to tell groups of samples apart, where the groups are known a priori. Once a means of discrimination among groups has been established using samples whose groups are known, unknown samples may be classified into the original groups. Canonical analysis produces a way to display the maximum separation between groups in a graphic manner. Examples of applications of these methods in palynology are shown using data from Osgood Swamp, California, and from southern Arizona. These methods offer the advantages of reproducibility of results and speed in pattern description. Once the patterns in the data have been described, however, their interpretation must be done by the palynologist.
54

Post-fire Succession and Carbon Storage in the Northern Everglades

Unknown Date (has links)
Fire plays a key role in the ecology of the Everglades and is a ubiquitous tool for managing the structure, function, and ecosystem services of the Greater Everglades watershed. Decades of hydrologic modifications have led to the alteration of plant community composition and fire regime in much of the Everglades. To create a better understanding of post-fire recovery in sawgrass (Cladium jamaicense) communities, sawgrass marshes in the northern Everglades were studied along a chronosequence of time since fire and along a nutrient gradient. Areas closer to a water nutrient source and with fewer mean days dry contained greater total and dead aboveground graminoid biomass whereas live graminoid biomass was greater in areas with less time since fire and with fewer days dry. Post-fire characteristics of sawgrass marshes can provide insight on the effectiveness of fire management practices in the maintenance and restoration of quality habitat in the northern Everglades. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
55

Abundância, trofodinâmica, variabilidade genética e orientações para manejo da espécie invasora Procambarus clarkii (Girard, 1852) (DECAPODA, CAMBARIDAE) no sudeste brasileiro

Loureiro, Tainã Gonçalves January 2018 (has links)
O lagostim Norte-Americano Procambarus clarkii está dentre as espécies exóticas estabelecidas no Brasil, registrada no estado de São Paulo. Este crustáceo de água doce apresenta grande potencial de invasão (ampla plasticidade ecológica, elevada agressividade, enorme poder de dispersão). Além disso, é portador do oomiceto Aphanomyces astaci, ao qual as espécies de crustáceos nativas do Brasil podem não ser imunes. Inúmeros impactos já foram associados à presença de P. clarkii em várias partes do mundo, desde danos ao ecossistema até impactos sobre a biota nativa. A fim de contribuir com informações relevantes para o desenvolvimento de estratégias de manejo e mitigação de impacto desta espécie no Brasil, esta pesquisa (1) levantou informações sobre a dinâmica populacional e o efeito da sazonalidade na sua abundância, (2) aperfeiçoou e propôs um método padronizado, rápido e acessível para o monitoramento das populações invasoras, (3) testou uma abordagem para controle populacional, (4) verificou a ecologia alimentar e as variações sazonais e intrapopulacionais na dieta, relacionando estes aspectos com o potencial de impacto, (5) analisou a diversidade genética de 9 populações estabelecidas no estado de São Paulo através da utilização de marcadores mitocondriais, (6) sumarizou o panorama legal sobre espécies invasoras, e (7) propoe ações para o manejo de invasão de P. clarkii. Foi definida uma metodologia padronizada para o acompanhamento das populações invasoras de P. clarkii, baseada no método de Schumacher e Eschmeyer para populações fechadas. As análises de dinâmica populacional demonstraram que não há efeito sazonal na abundância da população estudada e que a mesma segue crescendo com taxas consideráveis. Após testar um método de controle populacional baseado na remoção periódica de indivíduos ao longo de um ano, percebeu-se que a abundância populacional aumentou drasticamente e que o controle populacional através de remoção intensiva de indivíduos deve ser mais eficiente que a remoção extensiva. O estudo da dieta evidenciou a voracidade destes lagostins, que se alimentam continuamente de itens diversificados, tanto de origem animal quanto vegetal. Sua alta plasticidade trófica contribui para o alto potencial de estabelecimento em novos ambientes, uma vez que pode utilizar diferentes recursos alimentares dependendo da sua disponibilidade. Esta alta diversidade alimentar também está relacionada com o elevado poder de impacto, uma vez que fontes de diferentes níveis tróficos são utilizadas como recurso alimentar, podendo gerar um desequilíbrio trófico multidirecional, além de ameaçar a abundância e diversidade das espécies consumidas. Nas análises moleculares, foram encontradas apenas 7 haplótipos compartilhados por indivíduos de populações diferentes. Nenhum haplótipo é compartilhado entre populações brasileiras e indivíduos de populações autóctones, embora 3 haplótipos sejam observados entre populações nativas e outros 4 sejam encontrados em algumas populações brasileiras. As diferentes abordagens analíticas aplicadas ao longo deste estudo indicam que P. clarkii está adequadamente adaptado às situações bióticas e abióticas encontradas no Brasil, não havendo nenhuma estação em que os indivíduos encontrem barreiras importantes que pudessem dificultar sua sobrevivência e expansão, de forma que é indiferente a época do ano em que se fará maiores investimentos em manejo das populações invasoras. / Amongst the non-native species currently stablished in Brazil, the North-American freshwater crayfish Procambarus clarkii, is highlighted. This species has notable economic importance worldwide due to its value to aquaculture among aquarists. The occurrence of this species in Brazil seems to be restricted to the State of São Paulo. Procambarus clarkii shows a remarkable potential of invasion as a result of its wide ecological plasticity, elevated aggressiveness and high dispersion capacity. Additionally, it hosts the oomycete Aphanomyces astaci, which might infect and threat native crustaceans. Many impacts were associated to the establishment of this crayfish around the world, from ecosystem disturbances to the harm of native biota. In order to provide relevant information to the development of impact mitigation actions and management strategies related to P. clarkii’s invasion in Brazil, this research (1) evaluated the population dynamics and the effect of seasonality on abundance of one invasive population, (2) adapted and proposed a standardized method to monitor invasive populations which is easily executed and of low budget, (3) tested an approach for population control, (4) verified the trophic ecology of this freshwater crayfish, considering seasonal and intrapopulational variations, relating this aspect to invasive capacity and potential impact, (5) analyzed the genetic variability of 9 populations established in the State of São Paulo through molecular mitochondrial markers, (6) summarized the legal panorama about invasive species, and (7) proposes management actions to deal with P. clarkii invasion. After testing some traditional methods for abundance estimation, in search for the most easily replicated and performed, we defined a standardized methodology to monitor invasive populations of P. clarkii, based in the estimation method of Schumacher and Eschmeyer for closed populations. The population dynamic analysis demonstrated that seasonality does not play a role in abundance and that the population is in continuous growth. The test of population control, based on periodical removal of individuals for a year did not result in a decrease on abundance as we expected. Thus, we believe that intensive animal removal might be more promising than extensive removal. The diet evaluation evidenced the remarkable voracity of this crayfish, which continuously feeds on a variety of items as macrophytes, algae, insects, crustaceans, mollusks, fishes and amphibians. We also found a notable trophic plasticity that must contribute for the great establishment and potential impact offered by this species. The molecular analysis showed 7 haplotypes that are shared among individuals from different populations. No haplotype is shared between native and Brazilian populations however, some native populations share 3 haplotypes and some Brazilian share 4 haplotypes. The variable approaches used in this thesis indicate that P. clarkii is adequately adapted to biotic and abiotic conditions in Brazil and it seems that there is no season in which individuals are under important ecological pressure related to population abundance or food resources, which would difficult their survivorship or range expansion. Thus, according to our data, there is no specific season in which population are subjected to any notable pressure that could be favored for management.
56

Wetland Conversion to large-scale agricultural production; implications on the livelihoods of rural communities, Yala Swamp, Lake Victoria basin, Kenya.

Kinaro, Zachary January 2008 (has links)
<p>Wetlands in most parts of the world are under threat of over-exploitation, loss and/or degradation partly due to agriculture and urban land uses.</p><p>Yala swamp, the largest fresh water wetland in Kenya measuring about 17,500 ha supports a large biodiversity and is source of livelihoods to communities around it. This study addresses the situation where part of this wetland is converted into large-scale agriculture by a multinational company, Dominion Farms (K) Ltd resulting into a conflict and controversy amongst key stakeholders. The study sought to investigate livelihood impacts this transformation has for the local community. It employs the concepts Stakeholder Analysis (SA) and Sustainable Livelihood Approaches (SLA) to asses the livelihood situation in terms of socio-economic conditions, rural infrastructure, income diversification, food security and environmental issues.</p><p>Data and information have been obtained from primary and secondary sources through field survey at the Yala wetland, in which randomly sampled small-scale farmers, fisher folk, Dominion employees, local leaders and informants, traders and other stakeholders were interviewed using questionnaire and other participatory methods. The main questions were designed to gain information about historical use of the wetland, changes in livelihoods and wetland before and after entry of Dominion Company into the area. From the study, it is evident that assessment of the key stakeholders in relation to this natural resource is of utmost importance for mapping out an acceptable management strategy for the wetland. Besides being cause to a conflict and controversy over control of and access to the swamp, the conversion has resulted into both negative and positive short-term and long-term livelihood impacts to the local community. The wetland being a contested resource with multiple users who claim a stake on it requires a holistic approach in its management that caters for divergent needs and views of key stakeholder groups. The study identifies management issues and proposes abroad vision for the future including recommendations for planning as well as suggestions for specific research needs that should form the basis of action</p>
57

Wetland Conversion to large-scale agricultural production; implications on the livelihoods of rural communities, Yala Swamp, Lake Victoria basin, Kenya.

Kinaro, Zachary January 2008 (has links)
<p>ABSTRACT</p><p>Wetlands in most parts of the world are under threat of over-exploitation, loss and/or degradation partly due to agriculture and urban land uses.</p><p>Yala swamp, the largest fresh water wetland in Kenya measuring about 17,500 ha supports a large biodiversity and is source of livelihoods to communities around it. This study addresses the situation where part of this wetland is converted into large-scale agriculture by a multinational company, Dominion Farms (K) Ltd. The study was undertaken to investigate the livelihood impacts this transformation has for the local community. It employs the concepts Stakeholder Analysis (SA) and Sustainable Livelihood Approaches (SLA) to assess the livelihood situation in terms of the socio-economic status, rural infrastructure, income diversification, food security and environmental management issues.</p><p>Data and information have been obtained from primary and secondary sources through field survey in the Yala wetland, in which randomly sampled small-scale farmers, fisher folk, Dominion employees, local leaders and informants, traders and other stakeholders were interviewed using questionnaire and other participatory methods. From the study, it is evident that assessment of the key stakeholders and their relation to this natural resource is of utmost importance for mapping out an acceptable management strategy for the wetland. Besides being cause to a conflict and controversy over control of and access to the swamp, the conversion has resulted into negative and positive short-term and long-term livelihood impacts to the local community. This contested resource with multiple users who claim a stake on it requires a holistic approach in its management that caters for divergent needs and views of key stakeholder groups. The study identifies management issues and proposes abroad vision for the future including recommendations for planning and research needs that should form the basis of action.</p>
58

Economic non-market valuation techniques : theory and application to ecosystems and ecosystem services : a case study of the restoration and preservation of Pekapeka Swamp : an application of the contingent valuation method in measuring the economic value of restoring and preserving ecosytem services in an impaired wetland : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Philosophy in Economics at Massey University, Palmerston North, New Zealand

Ndebele, Tom January 2009 (has links)
This thesis explores the theoretical basis of non-market valuation techniques; discusses in detail, the Contingent Valuation Method (CVM) and the Travel Cost Method (TCM); highlights the advantages and disadvantages of various non-market valuation techniques and their suitability under different conditions; and identifies the Contingent Valuation Method as the most appropriate non-market valuation technique to apply to Pekapeka Swamp, the case study site. The overall objective of the study is to apply the most appropriate non-market valuation technique to estimate the total economic value (TEV) of the restoration and preservation of Pekapeka Swamp and to test Hawke’s Bay Regional Council’s (HBRC) restoration programme for the Pekapeka Swamp using economic efficiency criteria. An appropriate contingent valuation mail survey questionnaire was designed to elicit responses to the dichotomous choice (DC) and open-ended valuation questions, and to collect socio-economic data and information on households’ attitude towards the environment. Responses to the survey questionnaire were analysed (using ordinary least squares regression for the open ended question, and logistic regression, for the DC question) to identify the factors that influence households’ willingness to pay (WTP) for the restoration and preservation of the Pekapeka Swamp and to estimate TEV. A number of functional forms of the logit and open-ended WTP models were fitted from which WTP functions were estimated. Households were asked a DC question followed by an open-ended question regarding the value they placed on the restoration and preservation of Pekapeka Swamp. Out of an initial mail-out of 958 questionnaires, an overall response rate of 46.13% was achieved after two follow-ups. Results from the final usable sample of 231, after removing protests and inconsistent responses, indicate that households in the Hawke’s Bay region would pay, on average, between NZ$30.00 and NZ$76.89 per annum for five years. Unit value ranges between NZ$17,898 and NZ$45,866 per hectare per year; and net present values for the restoration and preservation programme for Pekapeka Swamp based on our ‘best estimates’ range between NZ$5.05 million and NZ$18.20 million depending on the model and discount rate used.
59

Composição, estrutura e sazonalidade dos bandos mistos de aves em um remanescente de floresta paludosa no sul do Brasil

Silveira, André Barcellos January 2006 (has links)
Analisou-se a composição, estrutura e padrão sazonal de formação dos bandos mistos de aves em um remanescente de floresta paludosa na planície costeira do Rio Grande do Sul, sul do Brasil. Efetuaram-se amostragens mensais de fevereiro de 2005 a janeiro de 2006, com observações ocasionais em 2004 e janeiro de 2005. Pontos de contagem foram utilizados para estimar a abundância relativa das espécies integrantes dos bandos, e transecções foram efetuadas para as observações dos bandos mistos. Quarenta e sete espécies foram registradas como participantes em 92 bandos amostrados. O número de indivíduos foi positivamente correlacionado com o número de espécies dentro dos bandos. O pool dos não-passeriformes foi pobremente representado nos bandos, enquanto passeriformes suboscines e oscines foram igualmente representados na riqueza dos bandos. Onívoros e insetívoros foram bem representados, mas os nectarívoros tiveram apenas uma espécie integrante; frugívoros e granívoros foram ausentes nos bandos mistos.Espécies migratórias foram pouco representadas nos bandos, como havia sido verificado para outras áreas de Floresta Atlântica. A regularidade de uma espécie em integrar bandos mistos foi uma função de sua abundância relativa, e as espécies mais conspícuas tenderam a ser os integrantes mais regulares. Detectaram-se quinze co-ocorrências significativas em 153 combinações possíveis (10%), onze delas positivas e quatro negativas. Nenhum tipo estrutural de bandos foi distinguido por meio de análise de agrupamento. Associações positivas e negativas talvez estejam relacionadas a similaridades e dissimilaridades na distribuição vertical de cada par de espécies. Os atributos de freqüência, tamanho e riqueza dos bandos foram os menores encontrados em qualquer outro estudo na Floresta Atlântica. Os bandos formaram-se o ano inteiro no Faxinal, mas a freqüência, o tamanho e a riqueza dos bandos diferiram significativamente entre os meses e entre as estações. Osvalores máximos destes três atributos foram encontrados na estação não-reprodutiva, lembrando os padrões encontrados em outros locais da Floresta Atlântica. A combinação de um pequeno grupo de espécies abundantes e bem distribuídas, junto com uma baixa riqueza local talvez torne a estrutura dos bandos mistos no Faxinal menos variável do que em outros locais da Floresta Atlântica. / The composition, structure and seasonal pattern of formation of mixed-species bird flocks were analyzed in a swamp forest remnant in the coastal plain of Rio Grande do Sul state, southern Brazil. Field work was carried out monthly from February 2005 to January 2006, plus occasional observations in 2004 and January 2005. Point counts estimated the relative abundance of flocking species, and transects were performed to access data relative to the flocks. Forty seven species were recorded as participants in 92 flocks sampled. The number of individuals was positively correlated with the number of species within the flocks. Non-passerines pool is less represented in the flocks, while suboscines and oscines were equally represented in the flock richness. Omnivores and insectivores were well represented, but nectarivores had only one flocking species while frugivores and granivores were absent in flocks. Migrants had low representation on the composition and structure of flocks, as predicted for lowland Atlantic Forest areas. The regularity of a given species in to integrate flocks was a function of its relative abundance, and the species more conspicuous tended to be the more regular flock joiners. Fifteen significant co-occurrences of 153 possible pairs (10%) were detected, eleven positively and four negatively associated. None structural type of flocks was recognized through cluster analyses. Positive and negative associations were better explained by similarities or dissimilarities on vertical distribution of each species pair. The attributes of frequency, flock size and flock richness were the lowest found in any study on Atlantic Forest. Flocks were formed throughout the year at Faxinal, but frequency, flock size and flock richness differed significantly between months and between seasons. Higher values of these three attributes were found in non-breeding season, reaching the pattern found elsewhere in Atlantic Forest. The combination of a little set of abundant and well distributed speciesand low richness perhaps makes the flock structure at Faxinal less variable than that of Atlantic Forest elsewhere.
60

Composição, estrutura e sazonalidade dos bandos mistos de aves em um remanescente de floresta paludosa no sul do Brasil

Silveira, André Barcellos January 2006 (has links)
Analisou-se a composição, estrutura e padrão sazonal de formação dos bandos mistos de aves em um remanescente de floresta paludosa na planície costeira do Rio Grande do Sul, sul do Brasil. Efetuaram-se amostragens mensais de fevereiro de 2005 a janeiro de 2006, com observações ocasionais em 2004 e janeiro de 2005. Pontos de contagem foram utilizados para estimar a abundância relativa das espécies integrantes dos bandos, e transecções foram efetuadas para as observações dos bandos mistos. Quarenta e sete espécies foram registradas como participantes em 92 bandos amostrados. O número de indivíduos foi positivamente correlacionado com o número de espécies dentro dos bandos. O pool dos não-passeriformes foi pobremente representado nos bandos, enquanto passeriformes suboscines e oscines foram igualmente representados na riqueza dos bandos. Onívoros e insetívoros foram bem representados, mas os nectarívoros tiveram apenas uma espécie integrante; frugívoros e granívoros foram ausentes nos bandos mistos.Espécies migratórias foram pouco representadas nos bandos, como havia sido verificado para outras áreas de Floresta Atlântica. A regularidade de uma espécie em integrar bandos mistos foi uma função de sua abundância relativa, e as espécies mais conspícuas tenderam a ser os integrantes mais regulares. Detectaram-se quinze co-ocorrências significativas em 153 combinações possíveis (10%), onze delas positivas e quatro negativas. Nenhum tipo estrutural de bandos foi distinguido por meio de análise de agrupamento. Associações positivas e negativas talvez estejam relacionadas a similaridades e dissimilaridades na distribuição vertical de cada par de espécies. Os atributos de freqüência, tamanho e riqueza dos bandos foram os menores encontrados em qualquer outro estudo na Floresta Atlântica. Os bandos formaram-se o ano inteiro no Faxinal, mas a freqüência, o tamanho e a riqueza dos bandos diferiram significativamente entre os meses e entre as estações. Osvalores máximos destes três atributos foram encontrados na estação não-reprodutiva, lembrando os padrões encontrados em outros locais da Floresta Atlântica. A combinação de um pequeno grupo de espécies abundantes e bem distribuídas, junto com uma baixa riqueza local talvez torne a estrutura dos bandos mistos no Faxinal menos variável do que em outros locais da Floresta Atlântica. / The composition, structure and seasonal pattern of formation of mixed-species bird flocks were analyzed in a swamp forest remnant in the coastal plain of Rio Grande do Sul state, southern Brazil. Field work was carried out monthly from February 2005 to January 2006, plus occasional observations in 2004 and January 2005. Point counts estimated the relative abundance of flocking species, and transects were performed to access data relative to the flocks. Forty seven species were recorded as participants in 92 flocks sampled. The number of individuals was positively correlated with the number of species within the flocks. Non-passerines pool is less represented in the flocks, while suboscines and oscines were equally represented in the flock richness. Omnivores and insectivores were well represented, but nectarivores had only one flocking species while frugivores and granivores were absent in flocks. Migrants had low representation on the composition and structure of flocks, as predicted for lowland Atlantic Forest areas. The regularity of a given species in to integrate flocks was a function of its relative abundance, and the species more conspicuous tended to be the more regular flock joiners. Fifteen significant co-occurrences of 153 possible pairs (10%) were detected, eleven positively and four negatively associated. None structural type of flocks was recognized through cluster analyses. Positive and negative associations were better explained by similarities or dissimilarities on vertical distribution of each species pair. The attributes of frequency, flock size and flock richness were the lowest found in any study on Atlantic Forest. Flocks were formed throughout the year at Faxinal, but frequency, flock size and flock richness differed significantly between months and between seasons. Higher values of these three attributes were found in non-breeding season, reaching the pattern found elsewhere in Atlantic Forest. The combination of a little set of abundant and well distributed speciesand low richness perhaps makes the flock structure at Faxinal less variable than that of Atlantic Forest elsewhere.

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