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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.
191

Genetic diversity and genetic structuring at multiple spatial scales across the range of the Northern Leopard Frog, Rana pipiens

O'Donnell, Ryan P. 01 May 2012 (has links)
Despite a thorough understanding of the proximate mechanisms that drive genetic diversity, we are still very poor at predicting the genetic diversity of natural populations. Understanding patterns of genetic diversity is important for many reasons, including predicting species' adaptation to climate change and predicting the spread of invasive species, but it is particularly important for species that are declining. This dissertation attempts to explain patterns in genetic diversity at multiple spatial scales across the range of the Northern Leopard Frog, Rana pipiens, which is declining across large portions of its range. Genetic diversity is often lower in edge populations than in central populations. Genetic diversity may be reduced in edge populations per se, or populations that occur at the edge of the species' range may have low diversity because they have recently expanded into new habitat and thus show signs of founder effects. In Chapter 2, we tested several alternative hypotheses to explain genetic diversity across the species' range, and to explain why some edge populations may not show reduced genetic diversity. We found that genetic diversity was reduced in edge populations relative to central populations, but was not reduced in populations in previously glaciated areas relative to previously unglaciated areas; therefore position at range edge had a stronger effect in reducing diversity than recent colonization of new habitat. We found that genetic diversity declined linearly towards the range edge in one of two transects from range center to range edge. We concluded that genetic diversity in this species is generally reduced by position at the range edge, but that this effect may differ among edges. In Chapter 3, we tested the hypothesis that eastern and western populations were genetically distinct. We found two distinct clades that introgress in some markers but are distinct and defined by narrow boundaries in the eastern Great Lakes region in others. We concluded that genetic diversity in the Mississippi River region was elevated by the introgression of descendants from two Pleistocene refugia. In Chapter 4, we analyzed genetic diversity within populations throughout Arizona to assess potential source populations for reintroductions. We also analyzed mitochondrial DNA to determine whether any populations contained genetic material not native to the region. Populations in one area had high genetic diversity and high gene flow among populations, but also contained evidence of introduction of eastern frogs. We conclude that supplementing genetic diversity in other populations with translocations from this area is not recommended.
192

Génération de similaritons optiques dans des amplificateurs à fibres dopées erbium

Billet, C. 06 June 2006 (has links) (PDF)
L'autosimilarité et l'évolution asymptotique intermédiaire sont des caractéristiques fondamentales de divers phénomènes physiques. Les recherches dans le domaine de l'optique ont mené à la prévision et à l'observation du similariton, nouvelle classe d'impulsions optiques ultracourtes présentant un profil d'intensité parabolique et développé par celles-ci au cours de leur propagation dans un amplificateur fibré à dispersion normale. Au delà de leur intérêt scientifique, les similaritons optiques sont d'une importance pratique primordiale du fait que leur profil peut être maintenu sans distorsion dans toute fibre à dispersion normale active ou passive et parce qu'ils possèdent un chirp strictement linéaire facilitant leur compression. Ce mémoire s'attache à mettre en évidence les possibilités d'obtention de ce profil dans un amplificateur à fibre dopée erbium. Les impulsions expérimentales caractérisées à l'aide d'un dispositif FROG présentent un profil d'intensité ainsi qu'une dérive fréquentielle en accord avec les résultats issus d'un modèle numérique. Nous avons aussi été en mesure d'étudier la formation des ailes du similariton durant son régime asymptotique intermédiaire. Une application typique des similaritons consiste dans le développement de sources impulsionnelles ultracourtes; expérimentalement nous avons développé un dispositif femtoseconde totalement fibré combinant un amplificateur à similaritons et une fibre à bandes interdites photoniques.
193

Bridge Management System with Integrated Life Cycle Cost Optimization

Elbehairy, Hatem January 2007 (has links)
In recent years, infrastructure renewal has been a focus of attention in North America and around the world. Municipal and federal authorities are increasingly recognizing the need for life cycle cost analysis of infrastructure projects in order to facilitate proper prioritization and budgeting of maintenance operations. Several reports have highlighted the need to increase budgets with the goal of overcoming the backlog in maintaining infrastructure facilities. This situation is apparent in the case of bridge networks, which are considered vital links in the road network infrastructure. Because of harsh environments and increasing traffic volumes, bridges are deteriorating rapidly, rendering the task of managing this important asset a complex endeavour. While several bridge management systems (BMS) have been developed at the commercial and research level, they still have serious drawbacks, particularly in integrating bridge-level and network-level decisions, and handling extremely large optimization problems. To overcome these problems, this study presents an innovative bridge management framework that considers network-level and bridge-level decisions. The initial formulation of the proposed framework was limited to bridge deck management. The model has unique aspects: a deterioration model that uses optimized Markov chain matrices, a life cycle cost analysis that considers different repair strategies along the planning horizon, and a system that considers constraints, such as budget limits and desirable improvement in network condition. To optimize repair decisions for large networks that mathematical programming optimization are incapable of handling, four state-of-the art evolutionary algorithms are used: Genetic algorithms, shuffled frog leaping, particle swarm, and ant colony. These algorithms have been used to experiment on different problem sizes and formulations in order to determine the best optimization setup for further developments. Based on the experiments using the framework for the bridge deck, an expanded framework is presented that considers multiple bridge elements (ME-BMS) in a much larger formulation that can include thousands of bridges. Experiments were carried out in order to examine the framework’s performance on different numbers of bridges so that system parameters could be set to minimize the degradation in the system performance with the increase in numbers of bridges. The practicality of the ME-BMS was enhanced by the incorporation of two additional models: a user cost model that estimates the benefits gained in terms of the user cost after the repair decisions are implemented, and a work zone user cost model that minimizes user cost in work zones by deciding the optimal work zone strategy (nighttime shifts, weekend shifts, and continuous closure), also, decides on the best traffic control plan that suits the bridge configuration. To verify the ability of the developed ME-BMS to optimize repair decisions on both the network and project levels, a case study obtained from a transportation municipality was employed. Comparisons between the decisions provided by the ME-BMS and the municipality policy for making decisions indicated that the ME-BMS has great potential for optimizing repair decisions for bridge networks and for structuring the planning of the maintenance of transportation systems, thus leading to cost savings and more efficient sustainability of the transportation infrastructure.
194

TECTONIC CONTROLS ON LOWER DEVONIAN SANDSTONE DISTRIBUTION, ALABAMA

Solis, Michael P. 01 January 2010 (has links)
The Devonian Frog Mountain Formation thickens abruptly eastward across the Eastern Coosa thrust fault from <12 m on the west to>70 m on the east. The thin Frog Mountain on the west unconformably overlies the Cambrian-Ordovician Knox Group. The thin Frog Mountain (mostly shale) is overlain by the Mississippian Maury Shale (~1 m thick) and Fort Payne Chert (~50 m thick). The thick Frog Mountain on the east rests on the Middle Ordovician Athens Shale, a black shale >150 m thick. The Athens overlies the Knox Group. The thick Frog Mountain is nearly all sandstone and is overlain by Fort Payne Chert which is only ~1 m thick In the Eastern Coosa hanging wall, an upper-level out-of-the-syncline thrust fault with thick Frog Mountain in the hanging wall cuts more than 290 m stratigraphically down section from Athens to lower Knox in the footwall. The upper-level Frog Mountain thrust sheet crosses over the Eastern Coosa fault, and truncates folds in the Eastern Coosa footwall, moving ~2 km. The thick Frog Mountain Formation associated with the Eastern Coosa thrust sheet has been transported ~100 km cratonward. The Frog Mountain Formation was deposited over a low topographic high, which was in the location of the Blountian peripheral foreland bulge.
195

Baltymų kinazių ir kitų signalinių molekulių įtaką širdies miocitų L tipo kalcio srovei / Regulation of L-type calcium current by protein kinases and other signaling molecules in cardiac myocytes

Bogdelis, Andrius 24 October 2011 (has links)
Mūsų tyrymų tikslas – ištirti baltymų kinazės A, baltymų kinazės C, Src šeimos nereceptorinės baltymų tirozino kinazės ir jų signaliniuose keliuose dalyvaujančių molekulių įtaką L tipo kalcio srovei (ICa,L) fermentiniu būdu izoliuotuose iširdies miocituose. Šis tikslas buvo įgyvendintas sprendžiant keturias užduotis: 1) ištiriant varlės ir žiurkės skilvelių bei žmogaus prieširdžių miocitų β-adrenerginių receptorių signalinės grandinės elementų: β-adrenerginių receptorių, adenilatciklazės, fosfodiesterazių, baltymų kinazės A, baltymų fosfatazių (baltymų fosfatazės 1 ir baltymų fosfatazės 2A) bei įtampos valdomų L tipo kalcio kanalų bazinį aktyvumą; 2) ištiriant β3-adrenerginių receptorių įtaką žmogaus prieširdžių ICa,L ir susitraukimo jėgai; 3) nustatant Src šeimos nereceptorinės baltymų tirozino kinazės įtaką žmogaus prieširdžių ICa,L, taip pat jos aktyvinimo būdą ir veikimo vietą β-adrenerginių receptorių signalinėje grandinėje; 4) ištiriant baltymų kinazės C įtaka žmogaus prieširdžių ICa,L. / The objective of study was to investigate the role of protein kinase A, protein kinase C, Src family nonreceptor protein tyrosine kinases and other signaling molecules involved in pathways regulating the L-type calcium current (ICa,L) in enzymatically isolated cardiac myocytes. This objective was realized by resolving four tasks: 1) Examination of the basal activity of β-adrenergic receptor (β-AR) signaling cascade involving β-ARs, adenylyl cyclases, phosphodiesterases, protein kinase A, protein phosphatases (protein phosphatase 1 and protein phosphatase 2A) and L-type voltage-dependent calcium channels in frog and rat ventricular myocytes and human atrial myocytes; 2) Investigation of the role of β3-ARs in regulation of ICa,L and force of contraction in human atrium; 3) Exploration of the role of Src family nonreceptor tyrosine kinases in regulation of ICa,L, determining the route of their activation and site of action in β-AR signaling cascade of human atriual myocytes; 4) Probing of the impact of protein kinase C on basal and β-AR stimulated ICa,L in human atrial myocytes. The experiments were performed using whole-cell configuration of the pach-clamp technique.
196

Fontes e níveis de lipídios em dietas para girinos de rã-touro /

Pinto, Donovan Filipe Henrique. January 2018 (has links)
Orientador: Marta Verardino De Stéfani / Resumo: A adequação e a identificação da biodisponibilidade dos nutrientes da dieta a uma determinada espécie é realizada através de ensaios de digestibilidade. Porém, o método utilizado pode superestimar ou subestimar seus resultados. Neste sentido, o primeiro trabalho objetivou-se avaliar o coeficiente de digestibilidade aparente do lipídio (CDLIP) de quatro óleos de origem vegetal (milho, linhaça, canola e girassol) e dois de origem animal (resíduos de peixe e salmão) para girinos de rã-touro, comparando-se o método do lipídio digestível com o método clássico de substituição. Não houve diferença significativa entre os CDLIP de ambas metodologias, concluindo-se que ambas metodologias podem ser utilizadas para a determinação do CDLIP dos diferentes óleos. Entre os óleos avaliados o de girassol e linhaça tiveram melhor aproveitamento da gordura pelos girinos. Tendo em vista a importância dos lipídios como fonte de energia, o objetivo do segundo estudo foi avaliar o efeito de duas fontes (óleo de peixe e óleo de girassol) e níveis (3, 6, 9 e 12%) de óleo no desempenho e composição corporal de girinos de rã-touro. Os tipos e níveis de óleo não afetaram a sobrevivência em ambos ensaios. A maior porcentagem de gordura e de energia bruta corporal dos girinos alimentados com o óleo de peixe foram com 10,5% e 10,9% de EE na dieta respectivamente; nos girinos que receberam óleo de girassol foi de 9,3 e 9,7% de EE na dieta, respectivamente. Os ácidos graxos corporais dos girinos acompanharam ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The adequacy and the identification of the bioavailability of the nutrients of the diet to a given species is carried out by means of digestibility tests. However, the method used may overestimate or underestimate its results. In this sense, the first work was to evaluate the lipid apparent digestibility coefficient (CDLIP) of four vegetable oils (corn, linseed, canola and sunflower) and two of animal origin (fish and salmon residues) for tadpoles bull-frog, comparing the method of digestible lipid with the classic method of substitution. There was no significant difference between the CDLIP of both methodologies, concluding that both methodologies can be used for the determination of the CDLIP of the different oils. Among the evaluated oils the sunflower and linseed had better use of fat by the tadpoles. The objective of the second study was to evaluate the effect of two sources (fish oil and sunflower oil) and levels (3, 6, 9 and 12%) of oil in the performance and body composition of bullfrog tadpoles. Oil types and levels did not affect survival in both trials. The highest percentage of fat and gross body energy of tadpoles fed with fish oil were 10.5% and 10.9% EE in the diet, respectively; in tadpoles that received sunflower oil was 9.3 and 9.7% of EE in the diet, respectively. The fatty acids of the tadpoles followed the profile of the fatty acids of the diets. According to the results, the use of 10% EE in the diet for better weight gain, TCE and body fat of bullfrog t... (Complete abstract click electronic access below) / Doutor
197

Avaliação da qualidade de efluentes na criação de rã-touro (Lithobates catesbeianus) /

Borges, Fernanda de Freitas. January 2010 (has links)
Resumo: O estudo foi realizado no Setor de Ranicultura do Centro de Aquicultura da Universidade Estadual Paulista, Câmpus Jaboticabal/SP em dois períodos distintos, compreendendo uma fase de girinagem e uma fase de engorda no ciclo de criação de rã-touro. Os objetivos foram verificar as características físicas, químicas e microbiológicas da água de entrada e de saída dos tanques em cada fase do ciclo. Os resultados obtidos foram comparados com a legislação ambiental CONAMA 357 de 2005, para verificar se o manejo utilizado em cada fase causa alterações na qualidade da água. Foram analisadas as variáveis temperatura, pH, oxigênio dissolvido, condutividade elétrica, turbidez, nitrogênio amoniacal, nitrato, fósforo total, DBO5, DQO e Escherichia coli em cada etapa do ciclo. O delineamento experimental foi o Inteiramente Casualizado, com dois tratamentos, água de abastecimento e efluente e seis repetições (tanques) em um esquema de parcelas subdivididas, sendo as sub-parcelas as coletas no tempo. As coletas das amostras foram realizadas a cada quinze dias no período da manhã. Na fase de girino o experimento foi realizado entre novembro de 2008 e janeiro de 2009 e teve duração de 76 dias, até os animais completarem a metamorfose. Não foi observada diferença significativa (p>0,05) entre os tratamentos para temperatura, condutividade, turbidez, DQO e E. coli. Entretanto, esses parâmetros variaram nas diferentes coletas. As variáveis pH, oxigênio dissolvido, fósforo total, amônia, nitrato e DBO5 tiveram diferença significativa (p<0,05) entre os tratamentos. Porém, somente as concentrações de fósforo total e DBO5 encontraram-se acima da recomendada pela legislação. A fase de recria teve duração de 77 dias, compreendendo o período de novembro de 2009 a janeiro de 2010, até os animais atingirem o peso de abate. Todas as análises apresentaram diferença significativa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The study was performed at the frog culture Sector, Aquaculture Center, Sao Paulo State University, Campus Jaboticabal, SP in two different periods, including a tadpole and growout phase in the cycle of creation of the bullfrog. The objectives were to verify the physical, chemical and microbiological water inlet and outlet of the tanks at each stage of the cycle. The results were compared with environmental legislation CONAMA 357, by 2005, to verify whether management used at each stage cause changes in water quality. The variables temperature, pH, dissolved oxygen, electrical conductivity, turbidity, ammonia nitrogen, nitrate, total phosphorus, BOD5, COD and E. coli at each stage of the cycle. The experimental design was completely random, with two treatments, water supply and sewage and six repetitions (tanks) in a split plot, and the sub-plots samples collected over time. The collections of samples were taken fortnightly during the morning. At tadpole phase, the experiment was conducted between November 2008 and January 2009 and lasted 76 days until the animals complete metamorphosis. There was no significant difference (p> 0.05) among treatments for temperature, conductivity, turbidity, COD and E. coli. However, these parameters varied in different samples. The pH, dissolved oxygen, total phosphorus, ammonia, nitrate and BOD5 were significantly different (p<0.05) among treatments. But, only the concentrations of total phosphorus and BOD5 were found above the recommended legislation. The growing phase lasted 77 days, including the period November 2009 to January 2010, until the animals reach slaughter weight. All analysis showed significant differences (p<0.05) among treatments and between collections. The variables, dissolved oxygen, total phosphorus, ammonia, BOD5 and E. coli had their values above those permitted by law... (Complete abstract click electronic access below) / Orientador: Marta Verardino de Stéfani / Coorientador: Luiz Augusto do Amaral / Banca: Laudicéia Giacometti Lopes / Banca: Lúcia Helena Sipaúba Tavares / Mestre
198

Vztah velikosti na pozici v chóru u samců rosničky zelené (Hyla arborea) / Relationship between males' body size and position in the chorus in European tree frog (Hyla arborea)

STUPKOVÁ, Veronika January 2012 (has links)
Males of European tree frog are clustered in the chorus in order to attract females. Males were re-captured, their body size and position in chorus was recorded. Goal of this thesis was investigated a correlation between the males' body size and mating behaviour and their position in the chorus.
199

A influência da espécie exótica invasora Artocarpus heterophyllus (jaqueira) sobre a comunidade de anuros de serrapilheira em uma área de Mata Atlântica no Sudeste do Brasil / The influence of invasive alien species Artocarpus heterophyllus (Jackfruit) of litter frogs in an area of the Atlantic Rain Forest of southeastern Brazil

Marlon Almeida dos Santos 21 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O processo de introdução de espécies é reconhecido como a segunda causa mais importante de erosão da diversidade biológica em muitos ambientes no Brasil e no mundo. As espécies invasoras possuem não apenas o poder de sobrevivência e adaptação em outros ambientes, mas a capacidade de dominar a diversidade biológica nativa através da alteração das características básicas dos processos ecológicos naturais e das interações. A jaqueira, Artocarpus heterophyllus Lamarck (Moraceae), tem sua origem nas florestas tropicais da Índia, tendo sido introduzida no Brasil ainda no período Colonial e atualmente é invasora em áreas de Mata Atlântica. Este estudo fornece os primeiros dados sobre a influência da espécie exótica invasora Artocarpus heterophyllus sobre comunidades de anuros de folhiço. As amostragens foram realizadas em uma área de Mata Atlântica, no litoral sudoeste do estado do Rio de Janeiro, incluindo informações sobre riqueza de espécies, densidades específicas e parâmetros ambientais. Nosso estudo foi realizado no Parque Estadual da Ilha Grande entre janeiro de 2009 e março de 2011. Para amostrar a comunidade de anuros de folhiço usamos 154 parcelas de 5 x 5 m, sendo 77 delas em áreas com jaqueiras e 77 em áreas sem jaqueiras, totalizando 3.850 m de chão de floresta amostrados. Nós amostramos um total de 613 anuros habitando o chão da floresta, pertencentes a dez espécies: Brachycephalus didactylus; Chiasmocleis sp.; Haddadus binotatus; Ischnocnema guentheri; Ischnocnema octavioi; Ischnocnema parva; Leptodactylus marmoratus; Physalaemus signifer; Rhinnela ornata e Zachaenus parvulus. Seis das dez espécies foram comuns às áreas com e sem jaqueiras, sendo a similaridade entre as duas áreas de 60%. As áreas com jaqueiras tiveram o dobro (N = 18) de parcelas sem nenhum anfíbio. O número de anfíbios registrados nas parcelas com jaqueiras (38%) foi menor do que o encontrado nas áreas sem jaqueiras (62%). O anfíbio predominante no folhiço em ambas às condições foi Ischnocnema parva, tendo abundancia maior nas parcelas sem jaqueiras. A densidade total de anuros vivendo no chão da floresta nas áreas com jaqueiras (12,2 ind/100 m) foi menor que nas áreas sem jaqueiras (19,7 ind/100 m). Entre os parâmetros ambientais analisados os que possuíram maior influência sobre a abundância de anfíbios foram a profundidade do folhiço e o pH do solo. Os dados sugerem que a jaqueira, além de ocupar o habitat de espécies nativas, é capaz de promover alterações na estrutura desses habitats que irão intervir na fauna do local. / The process of species introduction is recognized as the second most important cause of biological diversity erosion in many environments in Brazil and worldwide. Invasive species have not only the power to survive and adapt in other environments, but also the ability to master the native biodiversity by altering the basic characteristics of natural ecological processes and interactions. The jackfruit tree, Artocarpus heterophyllus Lamarck (Moraceae), has its origin in the tropical forests of India, being introduced in Brazil during the Colonial period and is currently invading the Atlantic Forest. In this study we provide the first data about the influence of the invasive alien species Artocarpus heterophyllus on anuran communities. Samples were taken in an area of Atlantic Forest, on the Southwest coast of the State of Rio de Janeiro, and included information on species richness, density and environmental parameters. Our study was conducted at the Ilha Grande State Park, between January 2009 and March 2011. To sample the community of litter anurans we constructed 154 plots of 5 x 5 m, being 77 of them in areas with jackfruit and 77 in areas with no jackfruit, totaling 3.850m of forest floor sampled. We collected a total of 613 frogs inhabiting the forest floor, being distributed within ten species: Brachycephalus didactylus; Chiasmocleis sp.; Haddadus binotatus; Ischnocnema guentheri; Ischnocnema otavioi; Ischnocnema parva; Leptodactylus marmoratus; Physalaemus signifer; Rhinnela ornata and Zachaenus parvulus. Six of this species were common to areas with and without jackfruit, and the similarity between the two areas was 60%. Areas with jackfruit had the double (N = 18) of plots with no amphibian. The number of amphibians recorded in plots with jackfruit (38%) was lower than the number found in areas without jackfruit (62%). The predominant amphibian species in both conditions was Ischnocnema parva, which had greater abundance in plots without jackfruit. The total density of frogs living on the forest floor in areas with jackfruit (12.2 ind/100 m) was lower than in areas without jackfruit (19.7 ind/100 m). Among the environmental parameters analyzed those with greater influence on the abundance of amphibians were the depth of leaf litter and soil pH. The data suggested that the addition of jackfruit, besides occupying the habitat of native species, is able to promote changes in the structure of these habitats that may intervene in the local fauna.
200

A influência da espécie exótica invasora Artocarpus heterophyllus (jaqueira) sobre a comunidade de anuros de serrapilheira em uma área de Mata Atlântica no Sudeste do Brasil / The influence of invasive alien species Artocarpus heterophyllus (Jackfruit) of litter frogs in an area of the Atlantic Rain Forest of southeastern Brazil

Marlon Almeida dos Santos 21 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O processo de introdução de espécies é reconhecido como a segunda causa mais importante de erosão da diversidade biológica em muitos ambientes no Brasil e no mundo. As espécies invasoras possuem não apenas o poder de sobrevivência e adaptação em outros ambientes, mas a capacidade de dominar a diversidade biológica nativa através da alteração das características básicas dos processos ecológicos naturais e das interações. A jaqueira, Artocarpus heterophyllus Lamarck (Moraceae), tem sua origem nas florestas tropicais da Índia, tendo sido introduzida no Brasil ainda no período Colonial e atualmente é invasora em áreas de Mata Atlântica. Este estudo fornece os primeiros dados sobre a influência da espécie exótica invasora Artocarpus heterophyllus sobre comunidades de anuros de folhiço. As amostragens foram realizadas em uma área de Mata Atlântica, no litoral sudoeste do estado do Rio de Janeiro, incluindo informações sobre riqueza de espécies, densidades específicas e parâmetros ambientais. Nosso estudo foi realizado no Parque Estadual da Ilha Grande entre janeiro de 2009 e março de 2011. Para amostrar a comunidade de anuros de folhiço usamos 154 parcelas de 5 x 5 m, sendo 77 delas em áreas com jaqueiras e 77 em áreas sem jaqueiras, totalizando 3.850 m de chão de floresta amostrados. Nós amostramos um total de 613 anuros habitando o chão da floresta, pertencentes a dez espécies: Brachycephalus didactylus; Chiasmocleis sp.; Haddadus binotatus; Ischnocnema guentheri; Ischnocnema octavioi; Ischnocnema parva; Leptodactylus marmoratus; Physalaemus signifer; Rhinnela ornata e Zachaenus parvulus. Seis das dez espécies foram comuns às áreas com e sem jaqueiras, sendo a similaridade entre as duas áreas de 60%. As áreas com jaqueiras tiveram o dobro (N = 18) de parcelas sem nenhum anfíbio. O número de anfíbios registrados nas parcelas com jaqueiras (38%) foi menor do que o encontrado nas áreas sem jaqueiras (62%). O anfíbio predominante no folhiço em ambas às condições foi Ischnocnema parva, tendo abundancia maior nas parcelas sem jaqueiras. A densidade total de anuros vivendo no chão da floresta nas áreas com jaqueiras (12,2 ind/100 m) foi menor que nas áreas sem jaqueiras (19,7 ind/100 m). Entre os parâmetros ambientais analisados os que possuíram maior influência sobre a abundância de anfíbios foram a profundidade do folhiço e o pH do solo. Os dados sugerem que a jaqueira, além de ocupar o habitat de espécies nativas, é capaz de promover alterações na estrutura desses habitats que irão intervir na fauna do local. / The process of species introduction is recognized as the second most important cause of biological diversity erosion in many environments in Brazil and worldwide. Invasive species have not only the power to survive and adapt in other environments, but also the ability to master the native biodiversity by altering the basic characteristics of natural ecological processes and interactions. The jackfruit tree, Artocarpus heterophyllus Lamarck (Moraceae), has its origin in the tropical forests of India, being introduced in Brazil during the Colonial period and is currently invading the Atlantic Forest. In this study we provide the first data about the influence of the invasive alien species Artocarpus heterophyllus on anuran communities. Samples were taken in an area of Atlantic Forest, on the Southwest coast of the State of Rio de Janeiro, and included information on species richness, density and environmental parameters. Our study was conducted at the Ilha Grande State Park, between January 2009 and March 2011. To sample the community of litter anurans we constructed 154 plots of 5 x 5 m, being 77 of them in areas with jackfruit and 77 in areas with no jackfruit, totaling 3.850m of forest floor sampled. We collected a total of 613 frogs inhabiting the forest floor, being distributed within ten species: Brachycephalus didactylus; Chiasmocleis sp.; Haddadus binotatus; Ischnocnema guentheri; Ischnocnema otavioi; Ischnocnema parva; Leptodactylus marmoratus; Physalaemus signifer; Rhinnela ornata and Zachaenus parvulus. Six of this species were common to areas with and without jackfruit, and the similarity between the two areas was 60%. Areas with jackfruit had the double (N = 18) of plots with no amphibian. The number of amphibians recorded in plots with jackfruit (38%) was lower than the number found in areas without jackfruit (62%). The predominant amphibian species in both conditions was Ischnocnema parva, which had greater abundance in plots without jackfruit. The total density of frogs living on the forest floor in areas with jackfruit (12.2 ind/100 m) was lower than in areas without jackfruit (19.7 ind/100 m). Among the environmental parameters analyzed those with greater influence on the abundance of amphibians were the depth of leaf litter and soil pH. The data suggested that the addition of jackfruit, besides occupying the habitat of native species, is able to promote changes in the structure of these habitats that may intervene in the local fauna.

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