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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.
61

The diversity of aquatic insects in the Tsitsikamma region, with implications for aquatic ecosystem conservation

Bellingan, Terence Andrew January 2011 (has links)
As a result of research carried out within the last decade to assess the diversity of macroinvertebrates of the Salt River in the Western Cape Province, South Africa, surveys of macroinvertebrates of 20 sites on 11 selected rivers from the same mountain range source were undertaken. This was done to make a preliminary assessment of the conservation status of the rivers of this region. Aquatic insects from the orders Ephemeroptera, Odonata, Plecoptera, Megaloptera, Trichoptera and the dipteran family Simuliidae were collected using techniques to maximize the number of taxa found. The insects collected were identified to species level where possible. Water physicochemical parameters were recorded at all sites for each sampling trip to characterize these rivers and to establish a set of baseline data for future comparisons. These parameters included measurements made on site and analysis of the concentrations of all the major ions in water samples in the laboratory. Multivariate analyses including Principle Components Analysis and Canonical Correspondence Analysis were used to reveal patterns within the water physicochemistry and species distributional data. Results include the identification of 123 species from 70 genera and 30 families. A total of 31 species were found to be undescribed, of which 17 were not previously collected and are thus completely new to science. In addition, four of these species could not be placed into any known genus. The analysis of water physicochemistry showed a clear distinction between rivers of Table Mountain sandstone and Bokkeveld shale origin. Downstream effects of anthropogenic influences were discernable too. Distinct macroinvertebrate assemblages were found based upon stream order and water chemistry composition. pH proved to be the most important driver of invertebrate assemblage composition. The high levels of endemism of the macroinvertebrates found within the upper reaches of these rivers and their degree of ecological specialization make these systems a priority for the conservation of aquatic biodiversity on a national and global scale.
62

The effects of stream productivity on aquatic-terrestrial linkages

Burdon, Francis John January 2004 (has links)
The potential relationship between riparian arachnids and aquatic insect productivity was assessed in forest streams throughout the central South Island of New Zealand. Initially, a survey was conducted of thirty seven, first-third order forest streams. Streams were selected to represent a range of benthic invertebrate standing crops (as a surrogate measure of "productivity") from Banks Peninsula streams with relatively high benthic invertebrate densities to acid mine drainage streams near Reefton that were almost devoid of aquatic life. At each site benthic invertebrate densities and biomass were measured in riffle habitats and adjacent gravel bars were sampled for terrestrial invertebrates. At a sub-set of 16 sites, a 20 metre longitudinal web-building spider survey was conducted along each bank of the stream. As an additional component, a 20 metre transect starting at the stream margin and running perpendicularly into the forest was used to survey the density of web-building spiders with increasing distance from the stream. Results from the survey of in-situ stream insect biomass and gravel bar invertebrates showed a strong relationship between aquatic insect biomass and the biomass of riparian arachnids (R2 = 0.42, P < 0.001) having accounted for potentially confounding factors such as stream size, elevation, substrate and disturbance. The 20 metre longitudinal survey showed that streams with the highest in-situ insect biomass had significantly higher densities of web-building spiders along their banks (R2 = 0.28, P < 0.05), having accounted for potential confounding variables of elevation, habitat architecture and stream and channel width. The stream to forest survey showed a strong exponential decay in web-building spider densities with increasing distance from the stream (R2 = 0.96, P < 0.0001). Regardless of stream productivity web-building spiders were most abundant at the stream margins and rapidly declined to very low densities 20 metres from the stream. In order to further test the relationship between riparian web-building spider densities and stream insect productivity, a stream fertilization experiment was conducted on six first-second order streams in the Maimai experimental catchment, Reefton. Three streams were enriched by the addition of a fertiliser solution mainly consisting of sodium nitrate for seven months, and the other three streams were used as controls. Water chemistry, benthic invertebrate communities, emerging aquatic adults, and the densities of web-building spiders along the stream corridor and in the forest were monitored in three seasons (spring, summer and autumn) over the course of the nutrient-addition. By the end of the experiment, conductivity was significantly higher in nutrient-addition streams than in the control streams (F = 80.5, P < 0.001), but chlorophyll concentrations showed no significant differences between treatments. Both benthic mayfly densities (F = 6.15, P < 0.05) and the biomass of adult aquatic dipterans (Chironomidae, Simuliidae) (F = 9.25, P < 0.01) were significantly higher in nutrient-addition streams in the last sampling round. Spiders recorded from intercept traps indicated that by the end of the experiment spider activity was significantly higher within 2.5 metres of the nutrient-addition streams (F = 5.70, P < 0.01). However, seasonal densities of web-building spiders along the stream margin and in the forest decreased with no significant differences observed between nutrient-addition and control streams. The results from these studies indicate that adult insects emerging from streams represent an important source of prey that could influence the biomass and abundance of riparian arachnids. Additionally, the results imply that stream productivity and size could mediate the strength of the interaction between riparian and stream habitats. Moreover, feedback mechanisms present in both systems could have implications for such interactions. The elevated densities of web-building spiders observed at the stream margin led to the proposal of the "Highway Robber" hypothesis. This hypothesis suggests that such higher densities of spiders are the result of increased insect activity along the stream corridor: the emergence of adult aquatic insects was predicted to vary less over temporal and spatial scales than that of terrestrial insects due to the poorly synchronized life histories in many New Zealand stream insects. I conclude by suggesting that there are numerous anthropocentric perturbations such as loss of heterogeneity, introduced species, pollution and habitat degradation that could undermine and decouple the intimate linkages between aquatic and terrestrial ecosystems.
63

Contribution des insectes aquatiques émergeant des rivières à la fourniture de services écosystémiques pour l’agriculture / Ecosystem services provided to agriculture by aquatic insects emerging from rivers

Raitif, Julien 18 December 2018 (has links)
La connexion entre milieux aquatiques et terrestres a suscité l’intérêt de la communauté scientifique, notamment l’effet du transfert d’énergie et de matière sur le fonctionnement des écosystèmes adjacents. Beaucoup d’études se sont intéressées aux apports d’insectes aquatiques ailés dans les écosystèmes naturels, mais peu à leur impact en milieu agricole. En modifiant la production secondaire d’invertébrés aquatiques, les pratiques agricoles sont à même d’intensifier ou diminuer l’effet de ces apports aquatiques dans les terres agricoles et par conséquent la fourniture de services écosystémiques utiles à l’agriculture. Nous avons collecté des données d’émergences et de dispersion d’insectes aquatiques depuis plusieurs rivières dans des paysages agricoles. Les principaux groupes d’insectes émergents sont les trichoptères (56%), chironomidés (25%) et éphéméroptères (19%). Nous estimons la biomasse sèche émergente entre 1445 et 7374 mg m-2 an-1 selon les sites. Une majorité de ces insectes aquatiques se déposent sur une bande entre 0 et 10 mètres du bord de la rivière mais une proportion importante (45%) se dépose dans les cultures après 20 mètres. Nous apportons de nouvelles et prometteuses connaissances suggérant que les insectes aquatiques participent à la fourniture de plusieurs services écosystémiques (fertilisation, contrôle biologie, épuration de l’eau et pollinisation). En paysage agricole, une communauté d’insectes riche et abondant est nécessaire à la mise en place d’un système agricole durable. Nous pensons que le rôle des insectes aquatiques est à ce titre important et suggérons de nouvelles pistes de recherches pour l’agroécologie. / The connection between aquatic and terrestrial habitats has increased scientific interest in ecological subsidies, focusing on how the transfer of matter and energy between adjacent ecosystems can modify the ecosystems functioning. Much attention has focused on aquatic subsidies associated with winged aquatic insects in pristine areas, but their implication in agricultural landscapes is rarely considered. By altering the production of benthic macroinvertebrates, agricultural practices can increase or decrease the strength of aquatic subsidies and subsequently the provision of several ecosystem services to agriculture. We have monitored the emergence and inland dispersal of adult aquatic insects from several agricultural streams. Most emerging dry mass (DM) belong to Trichoptera (56%), Chironomidae (25%) and Ephemeroptera (19%). We estimate that annual emerging dry mass of aquatic insects ranged between 1445 and 7374 mg m-2 y-1 depending on stream. The majority of aquatic insects emerging falls between 0 and 10 meters from stream hedges. However, a great proportion (45%) though disperses and eventually falls after 20 meters from the stream. We provide new and promising evidence suggesting that winged stream insects can support several ecosystem services (soil fertilization, crop pest control, water purification and pollination). In agricultural landscapes, a rich and abundant insect community is necessary to promote sustainable practices, and we believe the role of aquatic subsidies in providing ecosystem services to agriculture is a new and promising field of research in agroecology.
64

A complexidade do substrato e o mesohabitat (remanso e corredeira) são farores que influenciam a fauna de Chironomidae (Diptera) em riachos do Brasil Central? / Are the substrate complexity and the mesohabitat (pools and riffles) factors that influence the fauna of Chironomidae (Diptera) in streams of Central Brazil?

Mazão, Gustavo Rincon 09 March 2009 (has links)
O presente trabalho teve o objetivo testar os efeitos da complexidade do substrato e do tipo de mesohabitat (remanso e corredeira) sobre a riqueza, a abundância e a composição de Chironomidae (Diptera) em riachos. O experimento foi realizado em 12 riachos do Brasil Central, onde em cada mesohabitat (remanso e corredeira) foram colocadas duas bandejas de plástico, uma contendo substrato com alta complexidade e outra contendo substrato com baixa complexidade. Estes substratos permaneceram no riacho durante 20 dias. Os efeitos da complexidade do substrato e dos mesohabitats não foram significativos nem sobre a riqueza padronizada nem sobre a abundância, por outro lado, o efeito do mesohabitat foi significativo sobre a composição faunística. O primeiro eixo da DCA (33% da variabilidade) separou claramente a fauna de remansos da de corredeiras. A análise de espécies indicadoras mostrou que Chironomus sp., Ablabesmyia sp.1, Ablabesmyia sp.2, Djalmabatista sp., Fittkauimyia sp., Labrundinia sp. indicaram o remanso, e Paratendipes sp., Polypedilum sp.2, Pentaneura sp., Rheotanytarsus sp.1, Corynoneura sp.2, Cricotopus sp.2, Lopescladius sp., Nanocladius sp.2, Parametriocnemus sp. e Thienemanniella sp. indicaram a corredeira. / The present study had the aim to test the effects of the substrate complexity and of the mesohabitat (pools and riffles) on the richness, abundance and composition of Chironomidae (Diptera) in streams. The experiment took place in 12 streams of Central Brazil. In each stream, two plastic trays were put in each one of the two studied mesohabitats (pool and riffle), one with higher complexity substrate and one with lower complexity substrate. These substrates were kept in the streams for 20 days. The effects of substrate complexity and of mesohabitat were not significative neither on the standarized richness nor on the abundance. On the other hand, the effect of mesohabitat was significative on the faunistic composition. The first axis of DCA (33% of variability) separated cleanly the fauna in pools from those in riffles. The indicator species analysis showed that Chironomus sp., Ablabesmyia sp.1, Ablabesmyia sp.2, Djalmabatista sp., Fittkauimyia sp., Labrundinia sp. indicated pools, and Paratendipes sp., Polypedilum sp.2, Pentaneura sp., Rheotanytarsus sp.1, Corynoneura sp.2, Cricotopus sp.2, Lopescladius sp., Nanocladius sp.2, Parametriocnemus sp. and Thienemanniella sp. indicated riffles.
65

Ciclo de vida, produtividade secundária, distribuição, alimentação e crescimento de Massartella brieni (Lestage) (Ephemeroptera: Leptophlebiidae) em riachos do Parque Estadual Intervales, Estado de São Paulo / Life cycle, secondary production, distribution, feeding habits and growth of Massartela brieni from streams of the Parque Estadual Intervales, State of São Paulo

Paciencia, Gabriel de Paula 29 July 2008 (has links)
O presente trabalho teve como objetivo geral estudar o ciclo de vida, a produtividade secundária, a distribuição, a alimentação e o crescimento de Massartela brieni em riachos do Parque Estadual Intervales, Estado de São Paulo. O material analisado foi coletado em seis pontos de coleta, um no córrego Roda d´Água, um no córrego Mirante, um no córrego Bocaina, dois no córrego Água Comprida e um no córrego Lajeado. Em todos os pontos, substrato rochoso foi coletado com um amostrador de Surber com 0,250 mm de malha, em cada amostragem foram feitas 10 subamostras aleatórias perfazendo o total de 1m2. No Córrego Bocaina, folhiço em corredeira e em remanso também foram amostrados com rede D (10 pacotes de folhiço com 0,01 m2 cada). As coletas foram feitas entre Setembro/1999 e Setembro/2001. A análise dos histogramas referentes ao número de indivíduos em diferentes classes de tamanho foi inconclusiva quanto ao voltinismo da espécie estudada. A produtividade secundária anual de Massartella brieni foi 4802,79 mg.m-2ano-1 para um CPI de 120 dias, 3842,24 mg.m-2ano-1 para um CPI de 150 dias e 3201,86 mg.m-2ano-1 para um CPI de 180 dias. Os resultados indicam que M. brieni ocorreu preferencialmente em locais com menor velocidade de água associados com acúmulo de folhiço. Não houve uma relação linear negativa entre a vazão, a precipitação (mês anterior) e a densidade de M. brieni no córrego Mirante. No entanto, foi possível observar que meses com maior vazão ou precipitação (mês anterior) nunca apresentaram altas densidades. Na maior parte dos meses, os períodos com baixas densidades também foram os que apresentaram menor biomassa, exceto para os meses de Março a Maio de 2000 (meses que ocorreram indivíduos de maior porte). Durante o crescimento a maior parte das estruturas da cabeça tiveram alometria negativa, enquanto que as do abdômen e a maior parte das do tórax tiveram alometria positiva. A mudança de forma da maxila (Deformação Relativa I) teve uma leve relação significativa com o crescimento de M. brieni. / The present work had as general aim to study the life cycle, secondary production, distribution, feeding habits and growth of Massartela brieni from streams of the Parque Estadual Intervales, State of São Paulo. The analyzed material was collected in six collection stations, one in Roda d´Água stream, one in Mirante stream, one in Bocaina stream, two in Água Comprida stream and one in Lajeado stream. In all stations, rocky substratum was collected with Surber sampler with 0,250 mm of mesh, in each sampling 10 sampling units were taken randomily, totalling 1m2. In the Bocaina stream, litter in riffles and in pools were also sampled with D net (10 litter patches with 0,01 m2 each). The collections were carried out between September/1999 and September/2001. The analysis of size frequency histograms representing the number of individuals in different classes of size was inconclusive in relation to voltinism of the studied species. The annual secondary production of Massartella brieni was 4802,79 mg.m-2yr-1 for a CPI of 120 days, 3842,24 mg.m-2yr-1 for a CPI of 150 days and 3201,86 mg.m-2yr-1 for a CPI of 180 days. The results indicate that M. brieni occurred preferentialy in sites with lesser water speed and with litter accumulations. There was not a negative linear relation between the discharge and the precipitation (previous month) with density of M. brieni in Mirante stream. However, it was possible to observe that months with higher discharge or precipitation (previous month) did not present high densities. For the most part of the months, the periods with low densities had lesser biomass, except for the months from March to May of 2000 (months in which individuals of larger size occurred). During the growth, the most of the structures of the head had negative allometry, whereas of the abdomen and most measurements of the thorax had positive allometry. The change of shape of the maxillae (Relative Warps I) had a slight significant relationship with the growth of M. brieni.
66

A complexidade do substrato e o mesohabitat (remanso e corredeira) são farores que influenciam a fauna de Chironomidae (Diptera) em riachos do Brasil Central? / Are the substrate complexity and the mesohabitat (pools and riffles) factors that influence the fauna of Chironomidae (Diptera) in streams of Central Brazil?

Gustavo Rincon Mazão 09 March 2009 (has links)
O presente trabalho teve o objetivo testar os efeitos da complexidade do substrato e do tipo de mesohabitat (remanso e corredeira) sobre a riqueza, a abundância e a composição de Chironomidae (Diptera) em riachos. O experimento foi realizado em 12 riachos do Brasil Central, onde em cada mesohabitat (remanso e corredeira) foram colocadas duas bandejas de plástico, uma contendo substrato com alta complexidade e outra contendo substrato com baixa complexidade. Estes substratos permaneceram no riacho durante 20 dias. Os efeitos da complexidade do substrato e dos mesohabitats não foram significativos nem sobre a riqueza padronizada nem sobre a abundância, por outro lado, o efeito do mesohabitat foi significativo sobre a composição faunística. O primeiro eixo da DCA (33% da variabilidade) separou claramente a fauna de remansos da de corredeiras. A análise de espécies indicadoras mostrou que Chironomus sp., Ablabesmyia sp.1, Ablabesmyia sp.2, Djalmabatista sp., Fittkauimyia sp., Labrundinia sp. indicaram o remanso, e Paratendipes sp., Polypedilum sp.2, Pentaneura sp., Rheotanytarsus sp.1, Corynoneura sp.2, Cricotopus sp.2, Lopescladius sp., Nanocladius sp.2, Parametriocnemus sp. e Thienemanniella sp. indicaram a corredeira. / The present study had the aim to test the effects of the substrate complexity and of the mesohabitat (pools and riffles) on the richness, abundance and composition of Chironomidae (Diptera) in streams. The experiment took place in 12 streams of Central Brazil. In each stream, two plastic trays were put in each one of the two studied mesohabitats (pool and riffle), one with higher complexity substrate and one with lower complexity substrate. These substrates were kept in the streams for 20 days. The effects of substrate complexity and of mesohabitat were not significative neither on the standarized richness nor on the abundance. On the other hand, the effect of mesohabitat was significative on the faunistic composition. The first axis of DCA (33% of variability) separated cleanly the fauna in pools from those in riffles. The indicator species analysis showed that Chironomus sp., Ablabesmyia sp.1, Ablabesmyia sp.2, Djalmabatista sp., Fittkauimyia sp., Labrundinia sp. indicated pools, and Paratendipes sp., Polypedilum sp.2, Pentaneura sp., Rheotanytarsus sp.1, Corynoneura sp.2, Cricotopus sp.2, Lopescladius sp., Nanocladius sp.2, Parametriocnemus sp. and Thienemanniella sp. indicated riffles.
67

Diversidade de Hydropsychidae Curtis e Leptoceridae Leach (Insecta, Trichoptera) em riachos do Parque Estadual Intervales, Serra de Paranapiacaba, Estado de São Paulo / Diversity of Hydropsychidae Curtis e Leptoceridae Leach (Insecta, Trichoptera) in streams of Parque Estadual Intervales, Serra de Paranapiacaba, Estado de São Paulo.

Moretto, Rafael Alberto 13 February 2012 (has links)
A presente dissertação de mestrado resume-se a um estudo da diversidade de Leptoceridae e Hydropsychidae (Insecta, Trichoptera) do Parque Estadual Intervales, Estado de São Paulo, objetivando diminuir as lacunas distribucionais das espécies e facilitar o acesso de tais informações a outros pesquisadores, fornecendo subsídios taxonômicos para futuros trabalhos ecológicos ou de cunho conservacionista, aumentando assim, o conhecimento sobre as famílias Leptoceridae e Hydropsychidae e, consequentemente, sobre a ordem Trichoptera. A coleta foi realizada em dez riachos entre os meses de julho e agosto de 2010. O material coletado foi triado, preparado e identificado até o nível taxonômico de espécie. Análises quantitativas e testes estatísticos foram realizados para a determinação da riqueza e a abundância das duas famílias, além de, a partir das informações bióticas e abióticas nos diferentes riachos e das localidades de coleta, tentar inferir quais fatores ambientais são determinantes na distribuição faunística de tricópteros entre os diferentes riachos. Foi criada também uma checklist para as espécies de Leptoceridae e Hydropsychidae que ocorrem no Parque Estadual Intervales. Com a análise do material coletado, foi possível o reconhecimento de novas espécies e novos registros de espécies para o Estado de São Paulo. As novas espécies foram descritas ou encaminhadas para tricopterólogos especialistas, aumentando assim o conhecimento taxonômico do grupo em questão e contribuindo diretamente para a diminuição entre a diferença no número de espécies descritas na literatura e as estimativas do número de espécies existentes. / This dissertation summarizes a study of the diversity of Leptoceridae and Hydropsychidae (Insecta, Trichoptera) in Parque Estadual Intervales streams, State of São Paulo, aiming to reduce the distributional gaps of species and facilitate the access of such information to other researchers, providing subsidies for future taxonomic or ecological studies and for nature conservation, and increasing the knowledge about the families Leptoceridae and Hydropsychidae and, consequently, of the order Trichoptera. Data were obtained between July and August 2010, when ten streams were sampled. The collected material was sorted, prepared and identified to the taxonomic level of species. Quantitative analysis and statistical tests were performed to determine the richness and abundance of the two families. Biotic and abiotic information from different streams and sampling localities were also analysed, trying to infer which environmental factors are determinant in the distribution of the fauna of caddisflies. A checklist of the species of Leptoceridae and Hydropsychidae from Parque Estadual Intervales is also presented. The analysis of the collected material showed the presence of new species; these were described or sent to experts, thus increasing the taxonomic knowledge of the Trichoptera and contributing to decrease the difference between the number of described species and estimates of the number of existing species.
68

Estrutura da fauna de invertebrados bentônicos de dois riachos da Bacia do Rio Paranapanema (São Paulo, Brasil)

Alves, Maria Ines Bulgari January 2017 (has links)
Orientador: Virgínia Sanches Uieda / Resumo: A remoção da vegetação ripária pode ser uma importante causa de redução da diversidade e alterações na distribuição de invertebrados bentônicos ao longo do curso de riachos. O presente trabalho foi realizado em trechos de terceira ordem de dois riachos, um trecho com mata ripária (fechado) e outro sem (aberto) em cada riacho, e em dois meses da estação seca de dois anos consecutivos, a fim de verificar possíveis alterações espaciais e temporais na estrutura da fauna de invertebrados bentônicos. Também foram coletados dados de 12 variáveis ambientais e analisados junto com a abundância da fauna com o objetivo de verificar a interação entre estes dois grupos de dados na diferenciação entre as quatro amostras realizadas (dois trechos e dois anos, por riacho). A manutenção ou retirada da vegetação ripária não atuou isoladamente sobre a estrutura da fauna de invertebrados bentônicos, a qual foi também influenciada pela posição (montante ou jusante) do trecho fechado e por características estruturais próprias de cada trecho estudado, como presença de intervenções antrópicas nas proximidades (açudes) e tipo de substrato do leito. No riacho que apresenta o trecho fechado a montante, a mata contribui com matéria orgânica em suspensão e detritos vegetais para o trecho aberto a jusante, aumentando a oferta de abrigo e alimento para a fauna, diversificada e abundante nos dois trechos. Por outro lado, a grande quantidade de macrófitas no trecho aberto, localizado a montante no outro riach... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Removal of riparian vegetation can be an important cause of reduced diversity and changes in the distribution of benthic invertebrates along streams. The present work was carried out in third order stretches of two streams, one stretch with riparian (closed) and one without (open) forest in each stream, and in two months of the dry season of two consecutive years, in order to verify possible changes Spatial and temporal changes in the fauna structure of benthic invertebrates. Data were also collected from 12 environmental variables and analyzed together with the abundance of the fauna, in order to verify the interaction between these two data groups in the differentiation between the four samples (two stretches and two years, by stream). The maintenance or removal of riparian vegetation did not act alone on the structure of the benthic invertebrate fauna, which was also influenced by the position (upstream or downstream) of the closed section and by the structural characteristics of each section studied, such as the presence of anthropic Proximities (weirs) and type of substrate of the bed. In the creek that presents the enclosed stretch upstream, the forest contributes with organic matter in suspension and vegetal debris for the open stretch downstream, increasing the offer of shelter and food for the fauna, diversified and abundant in both stretches. On the other hand, the large amount of macrophytes in the open section, located upstream in the other stream, provides a hete... (Complete abstract click electronic access below) / Mestre
69

Morfologia do g?nero Baetodes Needham & Murphy (Ephemeroptera: Baetidae) com filogenia do Complexo Baetodes / Morphology of the genus Baetodes Needham & Murphy (Ephemeroptera: Baetidae) with phylogeny of Baetodes Complex

SOUZA, Marcia Regina de 24 February 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-09-05T19:37:03Z No. of bitstreams: 1 2015 - Marcia Regina de Souza.pdf: 8881663 bytes, checksum: 131a869d3fb01beb94aa945ed1c8754d (MD5) / Made available in DSpace on 2017-09-05T19:37:03Z (GMT). No. of bitstreams: 1 2015 - Marcia Regina de Souza.pdf: 8881663 bytes, checksum: 131a869d3fb01beb94aa945ed1c8754d (MD5) Previous issue date: 2015-02-24 / CAPES / Baetidae is the second richest family of Ephemeroptera, with cosmopolitan distribution and with morphology based on nymphs. The Baetodes Complex groups six Neotropical genera of Baetidae: Baetodes, Lugoiops, Moribaetis, Mayobaetis and Spiritiops which share a posterior seta on tarsal claw. Baetodes, that provides the complex name, is the richest genus among the genera above. Adaptations to climber habit provide to Baetodes an unusual morphology different from no-reophilics genera. Account this and poorly drawn structures, some features of Baetodes create some doubts. On present work, we revised morphology of Baetodes, described new structures, improved generical description, provided a list and images of features with interspecifical variation and, also, proposed the use of new terms. Monophyly of Baetodes Complex was recovered excluding Spiritiops and adding Indobaetis. Prebaetodes and Baetodes were recovered to sister-group, as well Lugoiops and Mayobaetis. The presence of a posterior seta on tarsal claw and the presence of a distomedial projection on article I of forceps, as well as on some former works, were recovered synapomorphic to new Baetodes Complex. / Baetidae ? a segunda maior fam?lia da ordem Ephemeroptera em n?mero de esp?cies, possui distribui??o cosmopolita e tem a taxonomia descritiva baseada no est?gio ninfal. O Complexo Baetodes ? um grupo com seis g?neros neotropicais de Baetidae: Baetodes, Lugoiops, Moribaetis, Mayobaetis e Spiritiops que compartilham a presen?a da cerda posterior na garra tarsal. Baetodes, que d? nome ao complexo, ? o g?nero com maior n?mero de esp?cies dentre os seis g?neros supracitados. Adapta??es ao h?bito agarrante conferem a Baetodes uma morfologia que destoa dos g?neros n?o-re?filos de Baetidae. Em fun??o disso e de estruturas mal ilustradas, algumas caracter?sticas morfol?gicas de Baetodes atualmente ainda permanecem d?bias. No presente estudo a morfologia de Baetodes foi revisada, novas estruturas descritas, a descri??o gen?rica ampliada, caracter?sticas que variam entre as esp?cies foram diagnosticadas e ilustradas e, alguns novos termos propostos. O monofiletismo do Complexo Baetodes foi recuperado com exclus?o de Spiritiops e inclus?o de Indobaetis. Prebaetodes e Baetodes foram recuperados como grupos-irm?os, bem como Lugoiops e Mayobaetis. A presen?a da cerda posterior na garra tarsal e a presen?a da proje??o distomedial no art?culo I dos f?rceps, assim como em alguns estudos pr?vios, foram recuperados como sinapomorfias do novo Complexo Baetodes.
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Aquatic invertebrate fauna of Matapouri, Northland.

Pohe, Stephen Robert January 2008 (has links)
A study of the aquatic invertebrate communities from two locations (Location 1 and Location 2) within the Matapouri catchment in Northland, New Zealand, was conducted to assess community structure in differing local-scale habitats. Four data collection methods were utilised generating 33,058 adult or larval invertebrates. The sampling methods comprised benthic kick-sampling, sticky trapping, light trapping, and emergence trapping. For the sticky trapping and light trapping, sampling was carried out at three different sites (Sites 1–3) within each location. The sites were situated within three habitat types; native forest, native forest-fringe, and raupo wetland. Emergence trapping also commenced within the three sites, at both locations, but was discontinued after two months, due to the equipment being destroyed by consecutive flooding events (method described in Appendix 1). Benthic sampling was carried out within the Forest and Forest-fringe habitats. Benthic sampling, sticky trapping, and light trapping were carried out following a monthly schedule between June and November 2005. Conductivity, pH, and water temperature measurements were taken concurrently with benthic sampling on a monthly basis, while water velocity and substrate measurements were taken once to assist in habitat characterisation. Overall, 71 taxa were recorded by benthic sampling over the six month period, with a mean of approximately 30 taxa per site per month. In comparison with similar studies elsewhere in New Zealand, a figure of around 30 taxa per sample was high. The benthic macroinvertebrate fauna at all sites was dominated by Trichoptera (19 taxa), Diptera (16 taxa) and Ephemeroptera (10 taxa). This pattern of diversity is similar to that reported in other New Zealand studies. However, in contrast to previous studies, the leptophlebiid mayfly genus Deleatidium was not numerically dominant over the rest of the community, and other leptophlebiid genera (Acanthophlebia, Atalophlebioides, Mauiulus and Zephlebia) were equally represented, possibly reflecting niche partitioning between the groups. The genus Nesameletus was not recorded at any site, despite being one of the core mayfly species in New Zealand streams. The rare mayfly Isothraulus abditus was recorded at one of the forest locations. There are no published records of this species from Northland. Although acknowledged as another of the core New Zealand benthic taxa, the hydropsychid caddisfly Aoteapsyche was not recorded during the study. However, another hydropsychid, Orthopsyche, was commonly recorded, and these may be filling a similar niche to the Aoteapsyche genus. In contrast to the Trichoptera, Diptera, and Ephemeroptera, the Plecoptera fauna was relatively depauperate, probably reflecting the warmer climate of the region and lack of temperature-buffered spring-fed streams. Surprisingly, Zelandobius, a core New Zealand genus, was absent but is regularly recorded in Northland. A species of conservation interest, Spaniocercoides watti, currently recognised as a Northland endemic, was recorded in low numbers. There were no apparent trends in diversity or abundance of benthic invertebrates over time. Also, there were no significant differences in species diversity between the two locations. However, in many cases, taxa were more abundant at Location 2. This may have been due to steeper gradients at Location 2, and the consequent effects on substrate size and streambed stability, as all other physical factors appeared similar between locations. Although several significant differences of individual benthic taxa were recorded, no broad effect of habitat (sites) on species diversity was observable. However, at Location 2, abundances were significantly higher at Site 3 (Forest) compared to Site 2 (Forest-fringe). The reasons were uncertain, but may be attributed to higher retention of allochthonous organic materials, trapped by in-stream cover and larger substrates. Investigations of adult stages by sticky traps supported benthic results recording community compositions and abundances dominated by Trichoptera and Diptera. Plecoptera were poorly represented. Location 2 recorded higher abundances of taxa, particularly Ephemeroptera and Plecoptera. Investigations of adult stages by light traps however did not produce any statistically significant differences in abundances between sites, between locations, or between sites across locations, and it is believed to be due to limited sampling replication combined with some biases of light trapping. This study indicates that the aquatic invertebrate community at Matapouri is diverse but also reasonably representative. Several rare or uncommon insects inhabit the catchment. It is therefore important that Iwi and the local Landcare Group, who invited and supported this research, together with the Department of Conservation, continue their efforts in protecting these areas. The resident fauna have the capacity to restock areas downstream, which are intended to be improved and restored through sediment control and riparian management.

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