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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

Régulations biologiques de Cosmopolites sordidus dans le réseau trophique des bananeraies / Biological regulations of Cosmopolites sordidus in the food web of banana agroecosystems

Mollot, Grégory 12 December 2012 (has links)
Dans les agroécosystèmes, les réseaux trophiques sont souvent structurés à partir de la plante d’intérêt agronomique, qui permet aux herbivores qui lui sont associés de se développer, notamment les bioagresseurs. La monoculture de bananiers a permis au charançon du bananier (Cosmopolites sordidus) de prospérer. Les larves de C. sordidus se nourrissent exclusivement de bananiers et provoquent leur chute, réduisant fortement le rendement dans la plupart des régions de production. Cette thèse a cherché à élucider la structure et le fonctionnement du réseau trophique de la bananeraie et particulièrement les interactions trophiques qui lient le C. sordidus aux autres espèces. L’objectif appliqué en ligne de mire était de favoriser les prédateurs généralistes pour augmenter la régulation naturelle de C. sordidus.1. Quel est l’effet de l’ajout d’une plante de couverture sur la prédation de C. sordidus ? En utilisant une variété de méthodes – isotopes stables, piégeage, infestation artificielle de bananiers, nous avons testé avec succès l’hypothèse selon laquelle l’enherbement induit, via le développement de proies alternatives, un changement de régime alimentaire des prédateurs généralistes, une augmentation de leurs abondances et une plus forte prédation des oeufs de C. sordidus.2. Quel est la structure du réseau trophique ? Nous avons combiné le séquençage haut-débit (technologie 454) avec le concept de codes-barres à ADN pour identifier les proies présentes dans le contenu stomacal des consommateurs. Nous avons utilisé un marqueur chloroplastique (boucle P6 trnL) pour identifier le bol alimentaire des herbivores, et un marqueur mitochondrial (mini-CO1) pour les prédateurs. Cette approche a permis de détecter des espèces qui n’avaient pas été échantillonnées, d’identifier les prédateurs naturels de C. sordidus au champ, et de quantifier les interactions à l’échelle des populations.3. Comment la structure du réseau trophique peut-elle influencer la régulation de C. sordidus ? Nous avons cherché les différents éléments structuraux (motifs) présents dans le réseau trophique de deux agroécosystèmes bananiers (sur sol nu et sur sol enherbé), et analysé leurs fonctions. Nous avons notamment décelé un motif composé de 4 espèces (2 ressources et 2 consommateurs) qui est représenté en grand nombre par rapport à un modèle neutre de réseau trophique. Ce motif s’est révélé systématiquement déséquilibré en faveur d’une proie, ce qui démontre qu’une distribution asymétrique des forces d’interactions permet de structurer le réseau. L’analyse de la position de C. sordidus dans les motifs décelés a permis de révéler ses interactions préférentielles avec les autres espèces de la communauté.Cette thèse montre comment le couplage de méthodes innovantes et complémentaires permet d’avoir une approche globale du fonctionnement trophique de l’agroécosystème. Les résultats montrent l’importance des ressources primaires (autres que la plante cultivée) sur la structuration du réseau trophique des arthropodes et sur le potentiel de régulation des bioagresseurs. Ce travail illustre également le lien entre la structure globale d’une communauté et l’évaluation des fonctions qui y sont associées / In agroecosystems, food webs are often structured from the crop, which enables the associated herbivores, including pests, to develop. For instance, monoculture in banana fields allowed the development of the banana weevil (Cosmopolites sordidus) populations. Borrowing larvae of C. sordidus cause banana plants topple over, which dampens the yield in most production areas. In this Ph.D. thesis, we attempted to disclose the structure and function of the banana food web, and particularly the trophic interactions that link banana weevil to others species. The applied perspective was to enhance population of generalist predators in order to increase the natural regulation of the pest.1. What is the effect of adding a cover crop on the predation of the pest?By using a variety of methods - stable isotopes analyses, trapping, artificial infestation of banana trees, we successfully tested the hypothesis according to which the addition of a cover crop, by enabling population of alternative preys to develop in the system, induces a change in predator diet, an increase of predator densities, and a greater predation rate on the eggs of C. sordidus.2. How is structured the food web?We combined next generation sequencing (454 technology) with the DNA barcoding concept to identify prey into gut contents of consumers. We used a chloroplastic marker (trnL) to identify the diet of herbivores, and a mitochondrial marker (CO1) for predators. This approach enabled the detection of unexpected species, the identification of the natural enemies of the pest, and the weighting of trophic interactions at the population scale.3. How can food web structure influence pest regulation?We searched structural elements (network motifs) occurring in the food webs of two banana agroecosystems (on bare soil and with cover crop), and we inferred the system functions. We detected the “bi-fan” size-4 motif, which occurred more frequently in the cover cropped food web than in random food webs. Interestingly, this motif was unbalanced for one of the two resources, illustrating the asymmetrical distribution of interaction strengths that shapes food web structure. The analysis of the position of C. sordidus within key motifs revealed its preferential interactions with other species of the community.This Ph.D. thesis emphasizes how linking innovative and complementary methods provides a comprehensive approach of the trophic functioning of the banana agroecosystem. Our results show the importance of primary resources (other than the cultivated crop) on the structure of arthropods’ food webs and on the pest regulation potential. This work also illustrates the link between the community structure and the evaluation of associated functions (i.e. pest regulation)
12

Análise da perspectiva integrada do currículo flexibilizado na licenciatura em ciências da Universidade Federal do Paraná - setor litoral / Integrated perspective analysis of the flexible curriculum in licentiate degree course in sciences of the Universidade Federal do Paraná - setor litoral

Tatiana de Medeiros Canziani 04 December 2015 (has links)
Essa tese verifica, a partir de uma análise da representação de estudantes e professores do curso de Licenciatura em Ciências da Universidade Federal do Paraná Setor Litoral, como se estabelece a perspectiva integrada dos conteúdos curriculares específicos de Física, Química e Biologia e com os conteúdos pedagógicos na formação de professores generalistas. Esse encaminhamento implica, do ponto de vista legal e pedagógico, na análise dos pressupostos que regem a implementação de um currículo por áreas do saber e cuja formação pedagógica não é realizada na Faculdade de Educação. A discussão sobre o tema é relevante e pertinente ao cenário brasileiro atual uma vez que é legitimada pelas Diretrizes Curriculares Nacionais de Ensino Médio (DCNEM), de 2012, e pelo Projeto de Lei no. 6.840/2013, que propõe a alteração do disposto no Artigo no.36 da LDB, Lei no. 9.394/96, ao estabelecer o currículo do Ensino Médio por áreas de conhecimento. Com o intuito de repensar esse panorama, examina os motivos que levaram à retomada da oferta no país de cursos de licenciatura de cunho generalista como é o caso da licenciatura em Ciências, em comparação com os cursos polivantes de formação docente, de curta duração, da década de 60. O estudo demonstra que há uma mudança de perspectiva, de maneira lenta e incipiente, no panorama da educação brasileira que propõe o estabelecimento de currículos em uma perspectiva integrada e que supõe a necessidade de reorganização dos saberes de modo menos fragmentado e por meio de áreas de conhecimento. A partir dos pressupostos apresentados, essa tese assume a hipótese central de que, o modelo de formação de professores por áreas do conhecimento, construído a partir de uma perspectiva curricular integrada entre os conteúdos específicos e os conteúdos pedagógicos, constitui-se como um modelo inovador de curso de licenciatura. Essa hipótese se vale do princípio de que se rompe com o tradicional modelo de formação docente em que o conteúdo específico é mais importante do que a formação pedagógica, o que implica em um maior compromisso com a formação do professor e o papel social atribuído às universidades. É um estudo de caso, de cunho qualitativo, sobre o referido curso voltado à formação docente em Ciências Naturais para atuar no 6o a 9o ano, do Ensino Fundamental II, mas em processo de transformação para lecionar também no Ensino Médio. A pesquisa se realizou por meio de triangulação de dados captados por meio de levantamento bibliográfico, análise documental e pesquisa de campo desenvolvida através de observação de aulas e entrevistas. A partir da análise dos dados, essa tese verifica as contribuições e os problemas desse modelo de formação inicial de professores por áreas do conhecimento, em uma perspectiva integrada de conteúdos, que se apresenta como pioneiro na formação de professores generalistas, em licenciatura plena. / This thesis verifies, from an analysis of the representation of students and teachers of the Licentiate Degree Course in Sciences of the Universidade Federal do Paraná - Setor Litoral, how it establishes an integrated perspective of the specific curriculum contents of Physics, Chemistry and Biology and teaching contents of generalist teachers training. This referral implies, from a legal and a pedagogical point of view, on the analysis of conditions governing the implementation of a curriculum for areas of knowledge and which pedagogical training is not performed at the Faculty of Education. The discussion on the topic is relevant and pertinent to the current Brazilian scenario since it is legitimized by the Diretrizes Curriculares Nacionais de Ensino Médio (DCNEM), from 2012, and by the Projeto de Lei nº. 6.840/2013, that proposes an alteration on the Artigo nº.36 disposed on LDB, Lei no. 9.394/96, that establishes the Ensino Médio curriculum by areas of knowledge. In order to rethink this situation, examines the reasons that led to the resumption of supply in the country of generalist degree courses such as in Science, compared to polivant courses of teacher training, of short duration, in the 60s. The study shows that there is a change of perspective, slow and incipient, in the panorama of Brazilian education that proposes the establishment of curriculum in an integrated perspective and assuming the need for reorganization of knowledge in a less fragmented way and through areas knowledge. From the presented assumptions, this thesis takes the central hypothesis that the model of teacher training by areas of knowledge, built from an integrated curriculum perspective between specific content and pedagogical content, establishes an innovative model of licentiate degree course. This hypothesis relies on the principle that breaks with the traditional teacher training model where specific content is more important than pedagogical training, which implies a greater commitment to the teacher formation and the social role assigned to universities. This is a case study of qualitative character on the refered course aimed at teacher training in Natural Sciences to work in the 6º to 9º year of Ensino Fundamental II, but in the process of transformation to also teach in Ensino Médio. The survey was conducted by means of triangulation of data obtained through a literature review, document analysis and field research developed through classroom observation and interviews. From the data analysis, this thesis verifies the contributions and the problems of this initial training model for teachers by areas of knowledge, in an integrated content perspective, which presents itself as a pioneer in the training of generalist teachers, in full licentiate degree.
13

Dating anxiety and sexual intimacy anxiety in young people who harm sexually : a comparative study

Eagle, Deborah January 2015 (has links)
The present research aimed to address two questions. First, is dating anxiety associated with sexual intimacy anxiety? Second, do young people who report harmful sexual behaviour, as an offence or harmful dating behaviour, have higher levels of dating and sexual intimacy anxiety than young people who report no harm, non-sexual harm or sexual and non-sexual harm (generalists)? The Dating Anxiety Scale for Adolescents (DAS-A) was used to measure overall dating anxiety. Questions relating DAS-A sub-factors fear of negative evaluation and social distress - dating were amended to measure sexual intimacy anxiety. A scale to measure partnership anxiety and sexual behaviour anxiety were designed. Participants were 77 young people aged 13 to 18 years (M = 15.4, SD = 1.41). Forty-five (58%) of participants were female and 32 (42%) participants were male. Results found a strong, significant association between higher levels of dating anxiety and higher levels of sexual intimacy anxiety r(75) = .80, p < .001. Young people who reported a sexual offence had significantly higher sexual behaviour anxiety than non-sexual offence (M = 15.82, SD = 6.23, p = .005) and generalist offence groups (M = 21.77, SD = 6.53, p = .044). Despite no other significant differences, a pattern emerged that suggests young people who report harmful sexual or generalist dating behaviour may have higher dating and sexual intimacy anxieties. Furthermore, young people who report harmful dating behaviour may have higher anxieties than young people who report an offence. The implications of the findings for future harmful sexual behaviour and harmful dating behaviour research and practice are discussed.
14

Význam remízků a jejich ekologických vlastností pro ptáky v intenzivně obhospodařované zemědělské krajině / The importance of woodlots and their ecological characteristics for birds in an intensively managed agricultural landscape

Rajmonová, Lenka January 2019 (has links)
Various types of woody vegetation are a key biodiversity refugee in intensively managed agricultural landscapes. However, the role of woodlots, representing an important type of such a vegetation, remains overlooked so far. Whereas the previous studies focused on the effect of their area, shape and isolation, consequences of variation in their habitat quality for biodiversity were not assessed up to now. This thesis is thus one of the first studies focusing on woodlots as a specific habitat for birds in agricultural landscape. My goals were: (I) to find out what is the bird community composition of woodlots in a Czech landscape, (II) to find out, what are the key habitat predictors of bird species richness and abundance in woodlots, (III) to describe differences in habitat preferences among various guilds and (IV) to formulate recommendations for conservational practice. I surveyed birds in 82 woodlots in an intensively managed landscape in Central Bohemia, Czechia, and measured variables describing woodlots' habitat quality together with woodlots' area, shape, isolation and types of surrounding land-use. I recorded numerous forest and non-forest bird species (57 in total), including some endangered farmland birds. The habitat variables showing significant relationships to bird community...
15

O ensino de música nos anos iniciais em duas escolas municipais de Vera Cruz do Oeste PR

Lopes, Josiane Paula Maltauro 01 December 2010 (has links)
Made available in DSpace on 2016-12-08T17:06:52Z (GMT). No. of bitstreams: 1 Josiane.pdf: 732153 bytes, checksum: 6b79cebc35f7363f0fbafc307b5ba4b4 (MD5) Previous issue date: 2010-12-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research studies the musical education and action of two music teachers in municipal teaching system in Vera Cruz do Oeste Paraná, Brasil. The theoretical framework of the study is based on Tardif and researchers in musical education field who deal with the teaching knowledge of generalist teachers and music teachers. The main purpose of the study is to understand the action of the generalist teachers who teach music in primary school. Specifically, the study attempts to understand where they are being graduated and find out about music, that purposes they believe the music must take on at school, what are the necessities while teachers of this subject and how are these classes in the primary school. The specific purposes were: understanding the conception of the Education General Office and of the education coordinator of each school about it in the school curriculum; investigating the initial and continuous education of these teachers. The methodology adopted a multi-cases study with qualitative approach. A semi-structured interview and structured observation was used for data collection. The results showed the complexity in the construction and mobilization of educational and musical acquirements during the action of generalists teachers. The final considerations emphasize the necessity of investment in courses of continuous musical education for generalist teachers being able to develop meaningful musical activities in musical classes in the Primary School and to emphasize the importance to understand the action of generalists teachers as specialist part. Others research are suggested to deepen the study about generalists teachers and alternatives to establish music as curricular subject in the Primary School / Esta pesquisa estuda a atuação e a formação musical de duas professoras de música do sistema municipal de ensino de Vera Cruz do Oeste/PR. O referencial teórico deste estudo é Tardif e pesquisadores da área de Educação Musical que tratam dos saberes docentes de professores, professores generalistas e de professores de música. O objetivo principal desta pesquisa é entender a atuação de professoras generalistas que ministram a disciplina específica de música nos anos iniciais do Ensino Fundamental, tentando compreender onde buscam formar-se ou informar sobre música, que objetivos acreditam que a música deve assumir na escola, quais são suas necessidades enquanto professoras desta disciplina específica e como se configuram as aulas de música nos anos iniciais no contexto pesquisado. Os objetivos específicos foram: compreender as concepções da Secretaria de Educação e dos coordenadores pedagógicos de cada escola sobre a música no currículo escolar dos anos iniciais; investigar a formação inicial e continuada das professoras que ministram a disciplina de música. A metodologia utilizada foi o estudo multicasos com abordagem qualitativa. A coleta de dados foi feita através de entrevistas semi-estruturadas e observações estruturadas não-participantes. Os resultados apontam para a complexidade na construção e mobilização dos conhecimentos pedagógicos e musicais durante a atuação das professoras generalistas. As considerações finais enfatizam a necessidade de investir em cursos de formação musical para professores generalistas a fim de que possam desenvolver propostas significativas de aulas de música nos anos iniciais do Ensino Fundamental e destacam a importância de compreender a atuação de professores generalistas no papel de especialistas. Além disso, a implantação das aulas de música no currículo escolar dos anos iniciais do município de Vera Cruz do Oeste se constitui como um exemplo positivo para outras localidades. Outras pesquisas são sugeridas para aprofundamento do estudo sobre a atuação de professoras generalistas e sobre alternativas para implantar a música como disciplina curricular nos anos iniciais do Ensino Fundamental
16

Impact of changing environments on West African rainforest amphibian communities and their parasites in Ivory Coast. / Auswirkungen von Umweltveränderungen auf Westafrikanische Amphibien-Gemeinschaften und deren Parasiten in der Elfenbeinküste

Kpan, Tokouaho Flora 27 June 2022 (has links)
Umweltveränderungen durch natürliche und/oder menschliche Einflüsse (insbesondere der Verlust und die Fragmentierung von Lebensraum) sind wichtige Faktoren, die zum weltweiten Artenschwund beitragen. Einer der entscheidendsten Beiträge zum weltweiten Rückgang der biologischen Vielfalt, ist der kommerzielle Holzeinschlag. Insbesondere in tropischen Regenwäldern, etwa in Westafrika, ist dies besonders besorgniserregend, da wenig untersuchte, diverse Wirbeltiergemeinschaften von einem starken kommerziellen Holzeinschlag betroffen sind. Frühere Studien haben bereits die negativen Auswirkungen großflächiger Abholzung auf die taxonomische und funktionale Vielfalt von Amphibiengemeinschaften, aber auch auf die Gesundheit von Individuen identifiziert. Umweltveränderungen können sich also auch nachteilig auf eine Wirts- Parasit-Beziehung auswirken, was nicht zuletzt zu einer verringerten Überlebensfähigkeit der Wirtsarten führen kann. Die Untersuchung der Auswirkungen von Störungen Abholzung und Umweltveränderungen auf Amphibien, sowie auf bestehende Wirts-Parasiten-Beziehungen sind daher von größter Bedeutung um nachhaltige Waldwirtschaft und zukünftige Naturschutzmaßnahmen planen zu können. In dieser Arbeit möchte ich mittels eines Regenerationsgradienten nach einer Störung (Abholzung) untersuchen, wie sich die Dynamik einer Amphibiengemeinschaft verschiebt und wie diese Störung die Wirts-Parasit-Beziehung beeinflusst. Ich verwende einen kombinierten Datensatz (Amphibie [Wirt], Milbe [Parasit] und Umweltbedingungen [Habitat]) der über zwei Zeiträumen im Abstand von 15 Jahren (1999-2000 und 2016-2017) an identischen Standorten (vor 45 Jahren abgeholzter Wald und Primärwald) im Taï-Nationalpark (TNP) in der Elfenbeinküste gesammelt wurde, um die Anpassungsfähigkeit von Fröschen und ihren Parasiten an sich ändernde Umgebungen zu untersuchen. In einem ersten Artikel unterstreiche ich die Bedeutung auch kleiner Waldgebiete als potenzielle Quellen für unbeschriebene Biodiversität. In einem kleinen, nie zuvor untersuchten Sumpfwald in der südöstlichen Elfenbeinküste fand ich eine neue Blattstreufroschart der Gattung Phrynobatrachus. Anhand charakteristischer morphologischer Merkmale, einer beträchtlichen, molekulargenetischen Distanz zu anderen westafrikanischen Phrynobatrachus-Arten, sowie eines individuellen, männlichen Anzeigerufes beschreibe ich Phrynobatrachus tanoeensis sp. nov. als eine für die Wissenschaft neue Art. Im zweiten Artikel untersuche ich die Widerstandsfähigkeit westafrikanischer Frösche in Wäldern, die vor über 45 Jahren selektiv abgeholzt wurden. Ich vergleiche die Diversität, Abundanz, Zusammensetzung und den Lebensraum von Amphibiengemeinschaften in abgeholzten und Primärwäldern innerhalt zweier Zeiträume (2000 und 2016- 2017). Ich konnte herausarbeiten, dass sich die Struktur des zuvor abgeholzten Waldes im Laufe von 45 Jahren langsam der des Primärwaldes annäherte, wobei die sichtbarsten Veränderungen in den letzten 15 Jahren auftraten. Während ich 30 Jahre nach dem Holzeinschlag zwar keine Unterscheide mehr in der Diversität und Abundanz der Amphibiengemeinschaft zum Primärwald feststellen konnte, beobachtete ich jedoch eine fortschreitende Konvergenz der Zusammensetzung der Amphibiengesellschaften in beiden Waldtypen. In den zuvor abgeholzten Wäldern erholten sich mehrere waldspezialisierte Arten (FS), während die Zahl mehrerer Generalisten (FG) über den 15-jährigen Probenahmezeitraum stetig abnahm. Diese Ergebnisse deuten darauf hin, dass 45 Jahre nach der Abholzung der gestörte Lebensraum allmählich die Heterogenität des ungestörten Lebensraums annimmt, der in der in der Lage ist die originale Amphibiengemeinschaft aus Waldspezialisten (FS) zu erhalten. Im dritten Artikel untersuche ich die Faktoren, die zu einem erhöhten Milbenbefall in den Amphibiengesellschaften des TNP führen. Ich fand heraus, dass die Wirts-Parasit-Beziehung zwischen Milben der Gattung Endotrombicula sehr spezifisch auf Frösche der Gattung Phrynobatrachus zugeschnitten ist, da offensichtlich nur die vier Arten P. phyllophilus, P. alleni, P. villiersi und P. plicatus befallen werden. Ebenso zeigte sich der Milbenbefall abhängig von der Art (höchste Prävalenz bei P. phyllophilus gefolgt von P. alleni), des Geschlechts (höhere Prävalenz bei Männchen als bei Weibchen, sowohl bei P. alleni und P. phyllophilus), des Alters (höhere Prävalenz bei Erwachsenen als bei Jungtieren in P. alleni) sowie der Jahreszeit (höhere Prävalenz während der Regenzeit im Vergleich zur Trockenzeit bei P. phyllophilus). Ich diskutiere diese Ergebnisse mit Bezug auf die Ökologie der Endotrombicula-Milben, die stark von feuchten Bedingungen abhängig sind, sowie die Überschneidung dieser Bedingungen mit denen der Wirtsfroscharten überschneiden. Des Weiteren beobachtete ich, dass die Prävalenz des Milbenbefalls in den letzten 15 Jahren (1999-2000 bis 2016-2017) abgenommen hat. Dieser steht möglicherweise im Zusammenhang mit den lokalen Auswirkungen des Klimawandels, was die in den letzten Jahren deutlich zurückgegangenen Niederschläge erklären würde. Meine Arbeiten zeigen, dass das Verständnis der Vielfalt westafrikanischer Amphibien noch lange nicht vollständig ist. Es zeigt sich, dass weiterhin Forschungsarbeit geleistet werden muss, um den tatsächlichen Amphibienreichtum besser abschätzen zu können. Darüber hinaus habe ich gezeigt, dass sich Amphibiengemeinschaften in abgeholzten Wälder zurück zum ursprünglicheren Zustand regenerieren können, was die Bedeutung unterstreicht, genutzten Wäldern ausreichend Zeit zu lassen, um sich zu regenerieren. Ob die Milbenprävalenz tatsächlich auf Grund des Klimawandels abnahm, sollte in Zukunft genauer untersucht werden. / Environmental changes due to both natural phenomena and/or human disturbance (i.e. habitat loss, disturbance and fragmentation) are important factors contributing to global species declines. Commercial logging is amongst the greatest contributor to this disturbance resulting in widespread biodiversity declines. In tropical rainforests, particularly those of West Africa, this is particularly troubling as diverse vertebrate assemblages are subject to heavy commercial logging. Previous studies have identified negative impacts of these logging practices on the taxonomic and functional diversity of amphibian communities and species. Furthermore, logging and other environmental changes may affect host-parasite interactions, resulting in exacerbated negative impacts of these pressures and reduced survivability of host species. As such, determining the effects of logging on amphibians, their subsequent recovery following selective logged forest, and the effects of environmental change on host-parasite relationships, will be paramount for informing future conservation action. In this thesis, I aim to determine how amphibian community dynamics shift over a regeneration gradient following disturbance (logging), and how this disturbance influences amphibian-parasite interactions. I use combined data sets (amphibian, parasite and habitat) from two time periods 15 years apart (1999-2000 and 2016-2017) collected in identical sites (logged forest since 45 years and old growth forest) within Taï National Park (TNP) Ivory Coast, in order to examine the adaptive capacities of frogs and their parasites to changing environments. In the first paper, I underline the importance of forest, even small, as potential source of undescribed biodiversity. In that small swamp forest, never survey before located in southeastern Ivory Coast, I found a new leaf-litter species of the Phrynobatrachus genus. Based on morphological characteristics, considerable molecular genetic distance to other West African Phrynobatrachus species, as well as advertisement calls, I describe Phrynobatrachus tanoeensis sp. nov. as a species new to science. In the second paper, I investigate the resilience of West African frogs in forests selectively logged over 45 years ago by comparing data (amphibian diversity, abundance, composition and habitat) from previously logged and old growth forest over two time periods (2000 and 2016-2017). I found that the structure of previously logged forest slowly recovered toward old growth forest states over the course of 45 years, with most visible changes occurring in the last 15 years. I also found no changes in amphibian diversity and abundance in the previously logged forest over time but observed a progressive convergence of amphibian composition in previously logged forests toward that of unlogged forest amphibian communities. In contrast, several forest specialist species (FS) recovered, whilst forest generalist (FG) species declined in the previously logged forest over the 15 years sampling period. These findings suggest that 45 years since logging activities the previously logged forest gradually provides habitat heterogeneity capable of maintaining FS amphibian species and more intact amphibian communities. In paper 3, I investigate the factors leading to increased mite infestation in the amphibian assemblages of TNP. I found that mites of the Endotrombicula genus seem to be specific to Phrynobatrachus frogs and infested only four leaf-litter species (P. phyllophilus, P. alleni, P. villiersi and P. plicatus). I also found that mite infestation was associated with species (highest prevalence in P. phyllophilus followed by P. alleni), sex (higher prevalence in males than females in P. alleni and P. phyllophilus), age (higher adult prevalence than juveniles in P alleni) as well as season (higher prevalence during the wet compared to the dry season in P. phyllophilus). I discuss these findings with reference to the ecology of Endotrombicula mites which rely heavily on humid conditions, conditions which overlap with the reproductive requirements of the host taxa. Additionally, I observed that the prevalence of mite infestation decreased over the last 15 years (1999-2000 to 2016-2017). This decreased mite infestation over time is potentially linked to local climate change, which exhibited distinctly lower rainfall in recent years. These studies show that West African amphibian diversity is far to be complete. Thus, more survey work needs to be done in order to have an idea of amphibian richness. Additionally, I showed that to environmental changes in the context of recovery following logging have a positive impact on amphibian. Forest amphibian community recovers in the previously logged forest, which highlight the importance to leave those forest to regenerate. However, although mite prevalence decreased over time, future research of post logging restoration and climate change impact on mite prevalence need be more investigate.

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