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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.
11

Caractérisation de la dynamique de population de l’épinoche à trois épines, Gasterosteus aculeatus, dans un mésocosme lotique : Application à l'évaluation des effets du bisphénol A dans un contexte écosystémique. / Caracterisation of the population dynamaic of three-spined sticklebacks, Gasterosteus aculeatus, in lotic mesocosms : apllication to risk assessment of bisphenol A in ecosystemic context.

Kermoysan, Goulwen de 13 September 2013 (has links)
Les tests écotoxicologiques en conditions écosystémiques, tels que ceux que l’on peut réaliser en mésocosmes,présentent une plus grande pertinence écologique que les tests normalisés en laboratoire. Ilspermettent d’intégrer les interactions complexes entre les espèces, entre le biotope et la biocénose. Cependant,en contrepartie de leur complexité, ces systèmes présentent une variabilité importante qu’il s’agitde réduire, par une standardisation expérimentale poussée, ou d’identifier les facteurs explicatifs pourmieux mettre en lumière des différences entre traitements. Dans le cadre de cette thèse, nous avons enoutre fait le choix d’une espèce sur laquelle focaliser nos efforts, le poisson, ici l’épinoche à trois épines,Gasterosteus aculeatus, en le considérant comme un bon indicateur de l’état de santé du mésocosme. Ilnous est apparu plus judicieux, dans le cadre des études en mésocosmes, de se concentrer sur une espèceintégratrice en parallèle d’une analyse globale d’abondance des espèces.L’objectif de cette thèse était donc de mieux comprendre la dynamique de populations de l’épinoche àtrois épines dans les mésocosmes de l’Ineris afin d’améliorer les protocoles utilisés et l’analyse des donnéesobtenues lors des études écotoxicologiques. Pour y parvenir, des expériences ont été réalisées afinde caractériser les processus et les traits d’histoire de vie de l’espèce dans notre site d’étude ; un protocolea été proposé pour effectuer des expériences en mésocosmes ciblées sur l’étude de la dynamique despoissons ; deux années d’expérience ont permis d’acquérir des données en conditions témoins et de mieuxsaisir les facteurs confondants ; nous avons mis en application nos connaissances en évaluant les effets dubisphénol A (BPA) sur la dynamique de population de poissons exposés à 0, 1, 10 et 100 μg/L de BPA.Nous avons ainsi pu décrire et expliquer la dynamique de la population de l’épinoche dans les mésocosmespar quatre phases distinctes : une augmentation massive des effectifs en raison de la reproduction desfondateurs ; une diminution importante des effectifs en raison d’une saturation des capacités du système ;une faible reprise ; une nouvelle chute à la fin de la période de reproduction. S’agissant du BPA, des effetssignificatifs ont été mis en évidence sur les individus (atrophie des gonades), mais également à l’échellede la population (structure de la population). / Ecotoxicity tests in ecosystemic conditions, such as those that can be performed in mesocosms, providea substantial ecological relevance. They permit to integrate complex inter-species interactions, interactionsbetween the organisms and the environmental conditions, and permit to assess perturbations witha systemic view. However, in return, these systems present a high variability that should be reduced,through experimental standardization or by identifying explicative factors, to better assess the differencebetween the outputs of the different treatments. In this thesis, we also focused on one species, of fish,the three-spined stickleback (Gasterosteus aculeatus), considering that it is good indicator of the healthstatus of the experimental ecosystem. We suggest that is more appropriate to focus on an integrativespecies in parallel to a global analysis in the context of mesocosms studies.The goal of this thesis was thus to better understand sticklebacks population dynamics in INERIS mesocosmsto improve the experimental protocols and the data analysis in ecotoxicity studies. To achieve thisgoal, studies were performed to characterize life cycle traits and processes of the species ; an experimentalprotocol was proposed to perform mesocosms studies with a focus on fish population dynamics; the datafrom two years of mesocosms studies in control conditions permitted to better understand the confoundingfactors ; we applied the methodolgoy to assess the effects of bisphenol A (BPA) on fish populationdynamics with expsoure concentrations 0, 1, 10 and 100 μg/L BPA.We could describe and explain stickleback population dynamics divided by four periods: first a massiveabundance increase due to the first reproduction of the founders in the mesocosms; second an importantdecrease due to the saturation of the system ; third a short increase ; finaly a new drop due to the endof reproduction. For BPA, effects were observed both at individual and at population levels.
12

低攪乱な礫床河川に優占する造網型トビケラの固体群動態とそれに伴う河床固化に関する解析

田代, 喬, TASHIRO, Takashi, 渡邉, 慎多郎, WATANABE, Shintaro, 辻本, 哲郎, TSUJIMOTO, Tetsuro 02 1900 (has links)
No description available.
13

BIOLOGIA POPULACIONAL DE Aegla sp. n.. (CRUSTACEA, DECAPODA, AEGLIDAE) NO ARROIO PASSO TAQUARA, SÃO PEDRO DO SUL/RS

Trevisan, André 27 February 2008 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to evaluate some aspects of the biology of the anomuran crab Aegla sp. n.., for example: the size of onset of sexual maturity, the median size between males and females, the sexual proportion (monthly and in size classes), the reproductive period (based on ovigerous females frequency), recruitment, spatial and seasonal distribution and growth in natural environment. This crustacean is a new species which is in process of description. The study was realized in Passo Taquara brook, situated in São Pedro do Sul municipality, in central region of Rio Grande do Sul State. Samplings were monthly realized, from May/2005 to April/2006 in three sections of the stream. Traps containing bovine liver as lure and dip nets were used to collect the animals. Eight traps were placed in each section, with a distance of 10 meters between them. In each section a sampling effort of 20 minutes was realized.. All the captured specimens were sexed by inspection of the presence of pleopods in females and and/or position of the sexual gonopores (coxae of the third pereopods in females and coxae of the fifth pereopods in males). Specimens with less than 3 mm of cephalothoracic length were considered unsexed juveniles due to the impossibility of visualizing pleopods and genital pores. The following corporeal dimensions were measured using a digital caliper with 0.01 mm of precision: cephalothoracic length (CL), cephalothoracic width (CW), width of the second abdominal somite (AW), length of the right chela (RC), length of the left chela (LC) and height of the larger chela (HC). After the data register, crabs were returned to the stream, to the same places where they were collected. A total of 916 specimens was sampled, 17 unsexed juveniles, 601 males (166 juveniles and 435 adults) and 298 females (101 juveniles, 182 adults and 25 ovigerous). The size at the onset of sexual maturity was esteemed, using Mature I and II software, in 13.60 and 10.84 mm of cephalothoracic length for males and females, respectively. Males presented sizes significantly larger than females. The distribution in size classes showed was bimodal for both sexes indicating more than one age-group in the population. The sexual proportion was in agreement with the expected value (1:1) when analyzing the specimens sampled with nets, but differed when analyzing the total data. Ovigerous females were sampled in all stations of the year, but they were more frequent in winter. Juveniles were also sampled in all stations of the years, but more frequently in winter and spring. The water temperature registered in Passo Taquara brook was similar among sections (p>0.05), but it was statistically more elevated in summer (p<0.05). The values of pH registered in section 02 were slightly more alkaline than in the other sections, and statistic differences among seasons were also observed (p<0.05). The concentrations of dissolved oxygen in water did not differ among sections, but the values observed in summer were significantly smaller (p<0.05). The outflow did not show statistic differences among sections and seasons (p>0.05). observed relationships in The linear regression analysis did not present any relationship between the abundance of eglids and the abiotic parameters, including precipitation (p>0.05). The type of substrate seems to be the principal factor explaining the distribution of this species, as revealed by the values of the linear regression between quantity of rocks and abundance of Aegla sp. n.. (F1,11 = 19.53 p = 0.0016). The size of rocks did not affect the abundance of eglids at the sections sampled. The growth curves of cephalothorax estimated for males and females are described by the following equations: Ct = 28.00 [1 e-0.0047(t+10.63)] and Ct = 25.16 [1 e-0.0051(t+17.65)], respectively. The males were larger than females and the estimated longevity was three years for males and two and half years for females. Differences were observed in the mean and median sizes of the chelipeds, besides a differential growth of the right and left chelae of Aegla sp. n.. The objective of this work was to contribute for the knowledge about some biology aspects of Aegla sp. n.., aiming the conservation of the species. / O objetivo desse trabalho foi avaliar alguns aspectos da biologia de Aegla sp. n.., tais como: tamanho do início da maturidade sexual morfológica, tamanho mediano de machos e fêmeas, distribuição etária, proporção sexual geral e nas classes de tamanho do comprimento cefalotoráxico, período reprodutivo, recrutamento, distribuição espacial, temporal e crescimento em ambiente natural. Este crustáceo é uma espécie nova em processo de descrição. O presente estudo foi realizado no Arroio Passo Taquara, localizado no município de São Pedro do Sul, região central do estado do Rio Grande do Sul. Foram realizadas coletas mensais de maio de 2006 a abril de 2007 em três trechos do referido córrego. Os organismos foram coletados com o auxílio de armadilhas plásticas, sendo que foram dispostas oito por trecho a uma distância de dez metros uma da outra, e com um puçá de 30 x 40 cm de tamanho, fundo de 60 cm e panagem com malha de 0,2 mm, sendo que em cada trecho foi realizado um esforço amostral de 20 minutos por duas pessoas. Os organismos coletados foram sexados com base na presença de pleópodos nas fêmeas e ausência destes nos machos e/ou posição das aberturas genitais (na coxa do 3º par de pereiópodes das fêmeas e 5º par nos machos), quando não era possível a visualização de pleópodos uma lupa foi utilizada para a visualização dos poros genitais. Indivíduos com menos de 3 mm de comprimento cefalotoráxico foram considerados jovens não sexados por não apresentarem pleópodos e poros genitais desenvolvidos o suficiente para a uma visualização com confiabilidade. Os indivíduos tiveram as seguintes dimensões corporais mensuradas com um paquímetro digital com precisão de 0,01mm: Comprimento do cefalotórax (CC - da ponta do rostro até a borda posterior da carapaça), largura do cefalotórax (LC tomada na altura da sutura posterior a região gástrica), largura do segundo somito abdominal (LA), comprimento do própodo quelar esquerdo (CPE), comprimento do própodo quelar direito (CPD) e altura do maior própodo quelar (ALT). Obtidas as medidas e a sexagem, os organismos foram devolvidos no mesmo local de onde coletados. Foram amostrados 916 indivíduos, sendo 17 juvenis não sexados, 601 machos (166 juvenis e 435 adultos) e 298 fêmeas (101 jovens, 172 adultas e 25 ovígeras). O tamanho do início da maturidade sexual morfológica foi estimado, utilizando os programas Mature I e II, em 13,60 e 10,84mm de comprimento cefalotoráxico para machos e fêmeas respectivamente. Machos e fêmeas apresentaram dimorfismo sexual quanto ao seu tamanho mediano. A distribuição em classes de tamanho se mostrou bimodal para machos e fêmeas, o que indica mais de um grupo etário na população. A proporção sexual seguiu o padrão esperado de 1:1, considerando-se os organismos coletados com puçá, fato que não foi observado com o conjunto total dos dados. Foram amostradas fêmeas ovígeras em todas as estações do ano, porém com maior intensidade no inverno, da mesma forma o recrutamento em Aegla sp. n.. apresentou-se de forma contínua ao longo do ano, porém com uma alta intensidade no inverno e primavera. A temperatura da água registrada no Arroio Passo Taquara não apresentou diferenças entre os trechos (p>0,05), porém no verão os valores foram estatisticamente mais elevados (p<0,05). Os valores de pH registrados no trecho 02 foram levemente mais alcalinos que nos demais trechos, da mesma forma foram observadas diferenças nos valores de pH entre as estações do ano (p<0,05). Os teores de oxigênio dissolvido (OD) na água não variaram significativamente entre os trechos (p>0,05), porém os valores de OD foram estatisticamente menores no verão (p<0,05). Não foi observada diferença estatística da vazão entre os trechos e estações do ano (p>0,05). Não foram observados valores significantes na análise de regressão linear entre a abundância de eglídeos e os parâmetros abióticos analisados (p>0,05). Não foi visualizada relação entre a precipitação pluviométrica e a abundância de Aegla sp. n.. no Arroio Passo Taquara (F1,11 = 0,02 p = 0,87). O tipo de substrato parece ser o principal fator que explica a distribuição dessa espécie no Arroio, esse fato fica mais evidente quando observamos o valor da regressão linear entre a quantidade de pedras e a abundância de Aegla sp. n.. (F1,11 = 19,53 p = 0,0016). O tamanho das pedras não se relaciona com a abundância nos três trechos amostrados. As curvas de crescimento do cefalotórax estimadas para machos e fêmeas são descritas pelas seguintes equações Ct = 28,00 [1 e-0,0047(t+10,63)] e Ct = 25,16 [1 e-0,0051(t+17,65)], respectivamente. Os machos atingiram maiores tamanhos que as fêmeas e a longevidade foi estimada em três anos para os machos e dois anos e meio para as fêmeas. Foram verificadas diferenças no tamanho médio e mediano dos quelípodos, além de um crescimento diferencial das quelas direita e esquerda em machos e fêmeas de Aegla sp. n.. O presente estudo busca contribuir para o conhecimento sobre os aspectos da biologia populacional na espécie Aegla sp. n.., visando a criação de medidas conservacionistas.
14

PADRÕES POPULACIONAIS DE MOSCAS FRUGÍVORAS (DIPTERA: TEPHRITOIDEA) EM UM FRAGMENTO DE FLORESTA SEMIDECIDUA E EM UM POMAR COMERCIAL DA REGIÃO DE DOURADOS-MS, BRASIL

Pereira, Veruska Lopes 19 March 2008 (has links)
Made available in DSpace on 2016-02-26T14:53:12Z (GMT). No. of bitstreams: 1 VeruskaLopesPereira.pdf: 546230 bytes, checksum: eaf7a47cfff5e212575e2312e3793c86 (MD5) Previous issue date: 2008-03-19 / Populational patterns of frugivorous flies (Diptera: Tephritoidea) in a fragment of Semidecidual Forest and in an orchard in the Region of Dourados, MS, Brazil. The Fruit flies are important pests in the word wide horticulture. These pests cause significant losses in the production of fruits and are responsible for the limitation in the free traffic of fruits, because their presence induce quarantine restrictions by importer countries of fruit and vegetables. The extension of loses are directelly related to the abundance of frugivorous fly populations. By other hand, the populations of Tephritoids are influenced by the abiotic (temperature, relative air humidity and rainfall) and biotic factors (host fruit availably and natural enemies action). This survey was carried out in a fragment semidecidual forest (22º12 S e 54º55 W) and in a commercial mixed orchard (22º 13 S 54º 43 W). The aim of this paper is: 1) to compare the abundance and the species richness of fruit flies caught in McPhail traps instaled in the edge and in the middle of the native forest, in the edge and middle of the commercial orchard; 2) survey the population fluctuation of the most abundant species of fruit fly in both ecosystems, loocking for some relationship with the abiotic factors and with plant phenology. C. capitata was the most abundant species, representing more than 80% of the caught adults of fruit flies. From Anastrepha spp. were identified 292 females, belonging to 12 species, being A. sororcula the most abundant fly (50,68%). C. capitata and A. sororcula were dominant. There were no significant differences in the abundance of frugivorous flies caught in the edge or in the middle of the forest neither in the edge and middle of the commercial orchard. Although, there are significant difference in the species diversity. The traps installed in the edge of the forest shows higher diversity index (H = 2.12). By other hand, the traps installed in the middle of commercial orchard captured higher species richness but with lower diversity index ((H = 0.408). The climatic factors were not the only ones that interfered in the population fluctuation of Anastrepha spp. and C. capitata in the surveyed environments. There was no correlation among the population fluctuation of the Anastrepha species with and the phenological stages of the fruit trees. But C. capitata populations were positively correlated with the stages of flowering, green fruits, ripe fruits and vegetative stages. The results in this paper corroborate with the prediction that in the ecotone there are higher species richness and diversity that in the middle of each one of the confronting ecosystems / Padrões Populacionais de Moscas Frugívoras (Diptera: Tephritoidea) em um Fragmento de Floresta Semidecidua e em um pomar Comercial da Região de Dourados, MS, Brasil. As moscas-das-frutas são consideradas importantes pragas da fruticultura mundial. Causam perdas significativas à produção e limitam o livre transporte de frutas devido às restrições quarentenárias impostas pelos países importadores. A extensão dos prejuízos tem relação direta com a abundância dos tefritídeos, que, por sua vez, pode ser influenciada por fatores abióticos (temperatura, umidade relativa do ar, do solo e precipitação pluviométrica) e bióticos (disponibilidade de hospedeiros e ação de inimigos naturais). O conhecimento da flutuação populacional de moscas-das-frutas é um requisito indispensável para o estabelecimento de um controle eficiente, pois permite viabilizar o planejamento de estratégias de manejo mais eficazes. A pesquisa foi conduzida em uma mata (22º12 S e 54º55 W) e um pomar comercial (22º 13 S 54º 43 W). Os objetivos deste trabalho foram: 1) comparar a abundância e a composição de espécies de moscas-das-frutas capturadas em armadilhas McPhail instaladas na margem e no interior de uma mata, na margem e no interior de um pomar comercial, e 2) avaliar a flutuação populacional das espécies de moscas-das-frutas mais abundantes nos ecossistemas e relacioná-las com fatores abióticos e bióticos. C. capitata foi à espécie mais abundante representando 80% dos adultos capturados. De Anastrepha foram identificadas 292 fêmeas pertencentes a 12 espécies, sendo A. sororcula a mais abundante (50,68%). C. capitata e A. sororcula foram dominantes. Não houve diferença significativa na abundância de moscas frugívoras capturadas na margem e no interior da mata, nem na margem e interior do pomar comercial. No entanto, houve diferença significativa na diversidade de espécies, as armadilhas instaladas na margem da mata apresentaram maiores índice de diversidade (H = 2,12). Por outro lado, as armadilhas instaladas no interior do pomar comercial capturaram maior número de espécies, embora com índice (H = 0,408) menor. Os fatores climáticos não foram os únicos determinantes da flutuação populacional de Anastrepha e C. capitata nas áreas estudadas. Não houve correlação entre a flutuação populacional das espécies de Anastrepha com os estágios fenológicos das plantas. No entanto, C. capitata apresentou correlação positiva com os estágios de floração, frutos verdes, frutos maduros e com os estágios vegetativos. Os resultados deste trabalho corroboram com a premissa de que, no ecótone, há uma maior riqueza e diversidade de espécie que no centro de cada um dos ecossistemas confrontantes
15

Bioecologia e controle biológico da cochonilha-rosada em Roraima

Marcelo Negrini 27 August 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A cochonilha-rosada, Maconellicoccus hirsutus (Hemiptera: Pseudococcidae), é uma praga recém-introduzida no Brasil que ameaça inúmeras culturas, especialmente a fruticultura e plantas ornamentais. Essa praga foi relatada pela primeira vez no Brasil em Roraima e até o momento não existem informações sobre bioecologia e controle desta praga no país. O objetivo desse trabalho foi estudar a biologia e a dinâmica populacional de M. hirsutus e de seus inimigos naturais em Roraima. O trabalho foi conduzido em laboratório para determinação dos parâmetros biológicos de M. hirsutus e em um cultivo de Annona squamosa L. (Anonaceae), para avaliação dos efeitos dos fatores climáticos, do controle biológico e do manejo da cultura sobre sua dinâmica populacional. Maconellicoccus hirsutus pode ter até nove gerações por ano, com 6,5 dias para dobrar sua população em tamanho. O número de fêmeas é cerca de três vezes maior que o de machos. A oviposição foi de 98 ovos/fêmea, com viabilidade de 97%. As populações de M. hirsutus foram maiores durante o período de frutificação e não apresentam correlação com as variáveis climáticas. Os níveis de infestação foram baixos (5,2 %), e isto pode estar relacionado às elevadas taxas de parasitismo (55,4 %) por Anagyrus kamali Moursi (Hymenoptera: Encyrtidae) e a predação por bicho-lixeiro (Chrysopidae). Árvores podadas apresentaram infestações menores que as encontradas em árvores não podadas. Maconellicoccus hirsutus possui elevado potencial biótico em condições de clima seco e quente, entretanto a ação de seus inimigos naturais associados às boas práticas de manejo podem manter baixos os níveis populacionais de M. hirsutus. / The pink hibiscus mealybug, Maconellicoccus hirsutus (Hemiptera: Pseudococcidae), is a pest recently introduced in Brazil threatens numerous crops, especially to orchards and ornamental plants. The first reported of this pest in Brazil was in Roraima, and there was not information about its bioecology and biological control in the country. The objective of this work was to study the biology and the population dynamic of M. hirsutus and of its natural enemies in Roraima. The work was conducted in the laboratory to determine the biological parameters of M. hirsutus and in an orchard of Annona squamosa L. (Anonaceae), to evaluate the effect of the climate, biological control and crop management on its dynamic population. Maconellicoccus hirsutus can have up to nine generations per year, with 6.5 days to double their population size. The number of females is about three times larger than that of males. The oviposition was 98 eggs / female, with viability of 97%. Populations of M. hirsutus were higher during the period of fruiting and it did not correlate with climate variables. The infestation levels were low (5.2%) and can be related to high parasitism rates (55.4%) by por Anagyrus kamali Moursi (Hymenoptera: Encyrtidae) and predation by lacewing (Chrysopidae). Pruned trees were less infested 40.95% lower than those trees not pruned. Maconellicoccus hirsutus has a high biotic potential in dry and warm weather conditions, however its natural enemies associated to a good management practices can maintain the population levels of M. hirsutus low.
16

Ecologie du copépode calanoïde Paracartia grani : implication dans le cycle de vie du parasite Marteilia refringens dans la lagune de Thau / Ecology of Paracartia grani (Copepoda, calanoida) : involvement in the life cycle of Marteilia refringens (Paramyxea) in Thau lagon (South of France)

Boyer, Séverine 11 December 2012 (has links)
Au cours de cette étude, le cycle de vie de Paracartia grani, un copépode calanoïde appartenant à la famille des Acartiidae, a été déterminé dans la lagune de Thau. En effet, ce copépode aurait une implication dans le cycle de vie du parasite Marteilia refringens, affectant les productions de bivalves. Un suivi bimensuel de la communauté mésozooplanctonique effectué sur deux ans à une station fixe dans la lagune a permis de déterminer que P. grani est l'espèce d'Acartiidae dominante en été. Son cycle de vie se compose de deux phases : une phase pélagique d'avril à janvier, et une phase benthique de février à début avril durant laquelle l'espèce subsiste dans le sédiment sous la forme d'œufs de diapause. L'analyse de la structure de la population (spectre de taille, contribution des stades de développement et sexe ratio) a permis de déterminer que 9 générations se succédaient pendant l'année. L'étude de l'influence de 3 paramètres environnementaux (température, salinité et concentration en chlorophylle a) sur la dynamique de ponte de l'espèce a révélé que la production d'œufs de P. grani était principalement régie par la température et que l'augmentation rapide de celle-ci au printemps permettait de déclencher l'éclosion des œufs de diapause. Le second objectif de cette étude s'est attaché à décrire la dynamique du parasite M. refringens chez P. grani et les bivalves Mytilus galloprovincialis et Ruditapes decussatus dans la lagune de Thau. Des analyses en histologie et hybridation in situ ont permis de décrire les différentes formes du parasite chez ces 3 espèces. La recherche de M. refringens par PCR chez les copépodites de P. grani a révélé la présence d'ADN de parasite de juin à novembre, période à laquelle de nouvelles moules apparaissent infectées. Les expériences de mesure de l'efficacité de rétention des différents stades de développement de P. grani par la moule ont permis de montrer que tous les stades de développement peuvent être impliqués dans le cycle de vie de M. refringens, en particulier les œufs du copépode qui ont par ailleurs présentés des résultats positifs en PCR. Notre étude a ainsi permis de préciser les interactions entre copépode, parasite et moules mais n'a pas permis d'élucider complètement le cycle de Marteilia refringens. Des questions restent posées concernant notamment les voies de transmission du parasite du copépode vers les moules et concernant l'impact potentiel du parasite sur le copépode lui-même. / In this study, the life cycle of Paracartia grani, a calanoid copepod belonging to the Acartiidae family was determined in Thau lagoon. Indeed, the copepod involvement in the life cycle of the parasite Marteilia refringens affecting the bivalves production is suspected. Mesozooplanktonic community was monitored twice a month over two years at a fixed station in the lagoon. Sampling has identified P. grani as the acartiid dominant species in summer. From April to January, the copepod is found in the water column while from February to early April it remains in the sediment as diapausing eggs. The analysis of the population structure (size spectrum, contribution of developmental stages and sex ratio) has revealed that there are 9 generations per year. The study of the influence of three environmental parameters (temperature, salinity and chlorophyll a concentration) on the dynamic nesting species indicated that P. grani egg production was mainly governed by temperature and its rapid increase in spring could trigger the hatching of diapause eggs.The second objective of this study aimed to describe the dynamics of the parasite M. refringens in P. grani, and in the bivalves Mytilus galloprovincialis and Ruditapes decussatus in the Thau lagoon. Histological and in situ hybridization analysis allowed describing the different forms of the parasite in these three species. Research of M. refringens by PCR in P. grani copepodites revealed that the parasite DNA presence in the copepod from June to November, when new mussels appeared infected. Experiments to measure the retention efficiency of the different stages of development of P. grani by mussels have shown that all developmental stages could be involved in M. refringens life cycle, especially copepod eggs that have also shown positive results by PCR. Our study has allowed clarifying interaction between copepods, parasites and mussels but not elucidate completely M. refringens life cycle. Questions remain especially regarding way of transmission of parasite from copepods to mussels and the potential impact of the parasite on the copepod itself.
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Use of Geographic Information System and Remote Sensing Technologies to Describe Mosquito Population Dynamics in the Ray Roberts Greenbelt, Denton County, Texas

Bolling, Bethany G. 05 1900 (has links)
A population survey was conducted from April through September 2002 on mosquito species occurring on the Ray Roberts Greenbelt, a riparian corridor used for public recreation on the Elm Fork of the Trinity River, in Denton County, Texas. ArcGIS software was used to set up a stratified random sampling design based on habitat parameters. Multivariate analyses of sampling data and climatic variables were used to describe spatial and temporal patterns of mosquito species. A total of 33 species were collected during this study belonging to the following genera: Aedes, Anopheles, Coquillettidia, Culex, Mansonia, Ochlerotatus, Orthopodomyia, Psorophora, Toxorhynchites, and Uranotaenia. Seasonal distributions of the dominant species revealed population fluctuations. Aedes vexans was the primary species collected in April and May, occurring in low numbers throughout the rest of the sampling period. Psorophora columbiae reached its highest population density in June, with a smaller peak occurring in late July. Present from May through the end of September, Culex erraticus was the most abundant species collected with major peaks in mid-June and the end of July. Abundance of Culex salinarius followed the same general trend as that for Cx. erraticus, but with smaller numbers. The specimens were tested for a variety of arboviruses by the Texas Department of Health. One pool of Cx. erraticus and Cx. salinarius, collected in August 2002, tested positive for West Nile virus. Variables that were important factors for determining dominant species abundance were temperature, wind speed, rain accumulation occurring one-week and two-weeks prior to sampling, number of day since last rain event, dew point, and average canopy coverage.
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Estudo da dinâmica populacional canina e felina e avaliação de ações para o equilíbrio dessas populações em área da cidade de São Paulo, SP, Brasil / Canine and feline population dynamic studies and evaluation of actions to these populations control in the São Paulo, SP, Brazil

Garcia, Rita de Cássia Maria 06 November 2009 (has links)
Procurou-se avaliar o comportamento da população humana do bairro Vargem Grande, município de São Paulo, SP, no período de 2005 a 2008, em relação à guarda de cães e gatos com ênfase aos aspectos sanitários e de bem estar. Paralelamente, buscou-se avaliar a dinâmica dessas populações animais e o impacto do controle reprodutivo e ações de saúde. Verificou-se que há uma alta renovação das populações canina e felina, conseqüência de elevadas taxas de mortalidade e natalidade, e que as ações de esterilização contaram com média adesão quando eram gratuitas, sendo que essa adesão diminuiu quando o processo passou a ter preços simbólicos. Houve uma diminuição das taxas de natalidade após a instituição das ações de esterilização, entretanto, há necessidade de acompanhamento das ações por um período mais extenso. / The aim of this study is to evaluate the behavior of the citizens living in the district of Vargem Grande, in São Paulo, SP, from 2005 to 2008, concerning the care of dogs and cats in its health and welfare aspects. It also aims at evaluating the dynamics of these animal populations and the impact of reproductive control measures and health actions. There is a high level of turnover rate in the canine and feline populations due to very high levels of mortality and birth rates. The population greeted free actions of spay and neuter with mild enthusiasm, but the participation decreased after introduction of a symbolic spay and neuter fee. There was a positive impact on the reduction of the birth rate in the population after the introduction of spay and neuter actions. Therefore, there is the need of following those actions for a longer period of time.
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Etude de la dynamique temporelle et environnementale contrôlant la mégafaune profonde vivant dans le Canyon de Barkley grâce à l'utilisation de l'observatoire Ocean Network Canada / Temporal dynamic and environnemental control of deep-sea megafauna in Barkley Canyon using Ocean Network Canada Observatory

Chauvet, Pauline 07 December 2018 (has links)
La dynamique temporelle des communautés de mégafaune épibenthique associées aux marges continentales demeurent peu connue. Face à ce constat, l’objectif de cette thèse est de mettre en évidence les échelles temporelles, les facteurs environnementaux et les processus qui régissent la dynamique des communautés vivant entre 400 et 1000 m de profondeur sur la pente et dans le Canyon de Barkley (Colombie-Britannique, Canada). Pour répondre à cet objectif, nous avons utilisé les séquences vidéo et les données océanographiques fournies sur chaque site par l’observatoire NEPTUNE d’Ocean Networks Canada. Ces données ont été couplées aux paramètres météorologiques et océanographiques de surface fournis par la bouée La Perouse bank, ainsi qu’aux images satellitaires (NASA) de concentration en chlorophylle de surface. Le gradient bathymétrique et oxique entre la pente et les sites du canyon sont vraisemblablement responsables de la composition spécifique distincte de ces communautés. Les variations saisonnières dominaient de la même manière la dynamique temporelle des trois communautés. Celles-ci ont été associées à la variation de production primaire de surface qui semble exercer son influence au travers de nombreux processus tels que l’arrivée de nourriture sur le fond ou par effets de cascade via la chaîne trophique. Nous avons également montré au travers de l’étude du cycle de vie du crabe tanneur Chionoecetes tanneri l’importance des cycles de vie des espèces et l’influence potentielle des interactions biotiques dans cette dynamique des communautés. Des indices concernant des phénomènes de plus longue durée, probablement de l’ordre de la décennie, confirment l’importance de continuer ce type de suivi sur un plus long terme. / The temporal dynamics of epibenthic megafaunal communities inhabiting continental margins remain poorly studied. The objectives of this thesis were to describe the time scales, environmental factors and processes influencing the temporal dynamic of the communities living at 900 and 1000 m depth at the wall and the axis (respectively) of Barkley Canyon and at the adjacent slope at 400m depth (British Columbia, Canada). To this end, we used video sequences and oceanographic data acquired at each site by Ocean Networks Canada's NEPTUNE observatory. These data were combined with meteorological and oceanographic surface parameters provided by the LaPerouse bank buoy and the NASA satellite images for surface chlorophyll concentration.The bathymetric and oxic gradients between the slope and the canyon sites are likely responsible for the distinct species compositions observed for these communities. Seasonal variations equally dominated the temporal dynamics of the three communities.These results were associated with the variations in primary surface production through many processes such as the arrival of food at the bottom and/or by cascading effects via the trophic food chain. The study of the life cycle of the tanner crab Chionoecetes tanneri revealed the importance of species life cycles and the potential influence of biotic interactions in communities’ temporal dynamics. Some clues on phenomena of longer duration, probably decadal, confirmed the importance of maintaining long-term monitoring in the area.
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Biologia populacional comparada de duas esp?cies de heliconius (Lepidoptera: Nymphalidae) em um ambiente sazonal de floresta atl?ntica do nordeste brasileiro

Lima, Luciana Lopes Ferreira de 28 August 2009 (has links)
Made available in DSpace on 2014-12-17T14:33:03Z (GMT). No. of bitstreams: 1 LucianaLFL.pdf: 2263314 bytes, checksum: 031f7f356fbeb6a00725098fb2fbe8c6 (MD5) Previous issue date: 2009-08-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Tropical environments often face strong seasonal variations in climate, such as alternate periods of dry and rain, that may often be important influence in the annual X the organisms lives. Here we assess how population dynamics of two butterfly species (Heliconius erato and Heliconius mepomene) respond to environmental and seasonal variations. A mark-release-recapture study carried out in an Atlantic forest reserve, 15 Km from Natal, Rio Grande do Norte, Brazil, for 3 years, during the dry and rainy season, with three visits weekly done. Information such as species, wing lenght, site of capture, pollen load and phenotype (number of spots) (in H. erato only) were noted for each capture. Seasonal variation exists in capture rates of the two species, with great capture rates during the rainy season. Despite finding differences in the mean density of individuals of the two species among the different collection areas, this difference was only significant between floodplain and central areas, and no influence of seasonality was observed in the mean density between the areas. Seasonality in wing size was only observed for H. erato, with larger wings during the rainy season. Females carried larger pollen loads than males both species, but species were similar. Only males differed seasonally, with larger pollen loads during the rainy season. The distribution of the number of wing spots did not vary between the dry and rainy seasons, and the number of spots in males and females was similar. Therefore, we conclude that there was a strong influence of seasonal variation in the population dynamic of the two Heliconius species, as well as in several aspects of their biology / Ambientes tropicais, assim como temperados, costumam se deparar com fortes varia??es sazonais em seus regimes clim?ticos, manifestadas atrav?s de per?odos alternados de seca e chuva, que podem ter pronunciada influ?ncia em diversos aspectos da vida dos organismos que neles habitam. O presente estudo teve como objetivo avaliar como a din?mica populacional de duas esp?cies de borboleta (Heliconius erato e Heliconius melpomene) responde ?s varia??es ambientais sazonais por elas enfrentadas. Um trabalho de marca??o e recaptura das esp?cies foi realizado em uma reserva de mata Atl?ntica localizada cerca de 15 km da cidade de Natal (RN), durante um per?odo de tr?s anos, nos meses mais secos e chuvosos do ano, com tr?s visitas semanais. Informa??es como esp?cie, comprimento alar, local de captura, idade, tamanho da carga pol?nica coletada e fen?tipo (n?mero de manchas na por??o ventral das asas anteriores) em H. erato foram obtidas para cada captura. Observou-se varia??o sazonal nas taxas de captura das duas esp?cies, com maior incid?ncia nos per?odos mais chuvosos, e baixa taxa de recaptura, principalmente nos per?odos mais secos. Apesar de encontrada diferen?a na densidade m?dia de indiv?duos das duas esp?cies entre as diferentes ?reas de coleta, esta foi significativa somente entre as ?reas de v?rzea e central, e n?o foi observada influ?ncia da sazonalidade na densidade m?dia entre as ?reas. O efeito da sazonalidade sobre o comprimento alar somente foi observado para H. erato, com indiv?duos coletados nos per?odos de chuva apresentando tamanhos superiores. F?meas coletaram maiores cargas pol?nicas do que machos nas duas esp?cies, mas n?o houve diferen?a quando comparadas as esp?cies entre si. Quando analisada a influ?ncia sazonal na obten??o de p?len, somente os machos apresentaram diverg?ncias entre as esta??es, com indiv?duos capturados nos per?odos mais chuvosos coletando maiores cargas pol?nicas. Quanto ? varia??o fenot?pica em H. erato, a distribui??o do n?mero de manchas n?o variou entre as esta??es seca e chuvosa, assim como n?o houve diferen?a no n?mero de manchas entre machos e f?meas. Podemos ent?o concluir que houve forte influ?ncia da varia??o sazonal na din?mica populacional das duas esp?cies de Heliconius, bem como em v?rios aspectos de sua biologia

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