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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.
91

Ecologia Populacional de Bugios-Ruivos (Alouatta guariba) nos Municípios de Porto Alegre e Viamão, RS, Brasil. / Population ecology of free-ranging brown howler monkeys (Alouatta guariba clamitans) in southern Brazil

Jardim, Marcia Maria de Assis 04 August 2018 (has links)
Orientador: Eleonore Zulnara Freire Setz / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-04T03:03:59Z (GMT). No. of bitstreams: 1 Jardim_MarciaMariadeAssis_D.pdf: 906770 bytes, checksum: 81b5c547024efb307fcafd7bdc02a344 (MD5) Previous issue date: 2005 / Resumo: Parâmetros populacionais são importantes indicadores de como as populações estão superando condições desfavoráveis e quais as suas perspectivas de sobrevivência a longo prazo. No período de dezembro de 1999 a dezembro de 2001, nós acompanhamos bimestralmente 10 grupos de bugios ruivos (Alouatta guariba clamitans) residentes em três fragmentos florestais nos municípios de Porto Alegre e Viamão, RS. Foram realizadas 13 expedições nas quais foram registrados os seguintes dados: data, horário, local e composição social de cada grupo. O intervalo médio entre os monitoramentos foi de 50,2 dias, totalizando 149 dias de campo e 219 encontros com grupos de bugios. O tamanho médio dos grupos foi de 8,2 indivíduos, sendo 1,3 machos adultos; 2,6 fêmeas adultas; 0,3 machos subadultos; 0,8 juvenis II; 2,3 juvenis I; 0,6 infantes II e 0,4 infantes I. Todos os grupos apresentaram alterações na composição social ao longo dos dois anos. Foram registrados 31 nascimentos, sendo a taxa anual de natalidade de 0,6 por fêmea adulta. O intervalo médio entre os nascimentos foi estimado em 14,7 meses. No decorrer do período, foram observados 16 casos de desaparecimentos (emigrações e/ou mortes) e uma imigração de uma fêmea adulta. Para enriquecimento da análise foram considerados mais cinco casos de desaparecimentos ocorridos em 1999 nos grupos de estudo, observados no período piloto e através de relatos de outros pesquisadores. Ao longo dos dois anos de monitoramento, o tamanho médio de área de vida estimado para os dez grupos foi de 4,4 ha pelo método do polígono mínimo convexo e 4,2 ha pelo método de esquadrinhamento (25x25m). A área de uso individual variou entre 0,2 a 1,1; com média de 0,5 ha por indivíduo. A sobreposição de áreas de uso variou de 0 a 39%. A densidade populacional e o tamanho de fragmentos foram os fatores mais determinantes no tamanho da área de uso e parecem ser melhores previsores para a espécie como um todo. Os resultados demonstraram um tamanho de grupo médio superior ao encontrado na literatura, altas taxas reprodutivas e variações relevantes na composição social dos grupos, indicando uma situação de crescimento populacional e dinâmica dos grupos intensa. A sobrevivência destas populações a longo prazo, no entanto, é incerta, devido à alta pressão de ocupação urbana e conseqüente fragmentação do hábitat, dificultando a dispersão efetiva dos indivíduos e aumentando as chances de depressão por endocruzamento / Abstract: Population parameters are important indicators of how populations are overcoming unfavourable conditions and of their perspectives of long term survival. Ten groups of brown howler monkeys (Alouatta guariba clamitans) living in three forest fragments around the cities of Porto Alegre and Viamão, RS, were followed bimonthly from December 1999 to December 2001. Thirteen expeditions were carried out and the following information was registered: date, time, location, and social composition of each group. The average interval between the expeditions was 50.2 days, with a total of 142 days on site and 214 encounters with groups of howler monkeys. The groups had an average size of 8.2 individuals, 1.3 adult males; 2.6 adult females; 0.3 subadult males; 0.8 juveniles II; 2.3 juveniles I; 0.6 infants II and 0.4 infants I. All groups presented alterations in social composition during the two-year period. Thirty-one births were registered, with an annual birth rate of 0.6 per adult female. The average interval between births was estimated in 14.7 months. Sixteen disappearances cases (emigrations and/or deaths) and the immigration of one adult female were observed during this period. Five additional disappearances cases within the study groups were considered in order to enhance the analysis. They all occurred in 1999 and were observed during the pilot period or reported by other researchers. The estimated average home range of all ten groups during the two-year monitoring was 4.4 ha using the minimum convex polygon method, and 4.2 ha using the grid method (25x25m). The area of individual use varied between 0.2 and 1.1, with an average of 0.5 ha per individual. The overlap of home range varied between 0 and 39%. Population density and size of fragments were the most important factors determining the size of use area and seem to be better predictors for the species as a whole. The results demonstrated an average group size superior to that found in literature, high reproductive rates and relevant variations in the social composition of groups, indicating population increase and intense group dynamics. However, the long term survival of these populations is uncertain due to the high pressure of urban occupation and the consequent fragmentation of their habitat, making the effective dispersal of individuals more difficult, and increasing the chances of depression by inbreeding / Doutorado / Ecologia / Doutor em Ecologia
92

Ocorrência, distribuição espaço-temporal e flutuação da população de percevejos pentatomídeos em sucessões culturais sob pivô central e áreas adjacentes / Ocurrence, spatial and temporal distribution of stink bugs (pentatomidae) population in crops successions under center pivot and adjacent areas

Aguero, Marcos Arturo Ferreira 31 March 2010 (has links)
The stink bugs are pests of soybean, corn, wheat and other crops. Economically, its management and key knowledge and behavior of their populations are needed to plan effective of action. The objective of this research was to investigate the occurrence, spatial-temporal distribution and population fluctuations of species of stink bugs in the succession of crops. The study was conduced during 12/2007 to 11/2009 on Jóia, RS, Brazil, in a commercial farming area of 162ha with no-tillage system, and center pivot irrigation (92ha) and adjacent areas (70ha). In the first year of study, 2007/08, 41ha pivot was planted with soybean [Glycine max (L.) Merrill] and 51ha, with corn (Zea mays L.), while in the offseason of 2008, with 41ha oat (Avena strigosa Schreb) associated with wild radish (Raphanus sativus L.) in succession to soybean and 51ha with oat in corn stubble. In the second year, the 2008/09 crop was planted soybeans in the entire pivot area (92ha) and adjacent areas (70ha). Already in the 2009 offseason, was season black oat (Avena sativa L.) in succession to soybean and wheat (Triticum aestivum L.) in the areas adjacent. Through the Campeiro CR-6® Software was generated a thematic map of the research and divided into regular grid of 63 cells 2.5 ha and their centers constituted the sampling points. The points were located with GPS. Samplings were made fortnightly in 2m², surveying vegetation, straw, crop residues and soil surface. Was noted the number of bugs nymphs from second instars and adults. The species were confirmed in the laboratory of Integrated Pest Management (LabMIP).To analyze the occurrence of population were used statistical series of geographical and temporal, is drawing up tables of frequency distribution of the population for each culture of the pivot, surrounding areas and places of refuge. The data were statistically analyzed by software BioEstat5®. We applied the binomial probability test between the populations of stink bugs on crops and surrounding areas to verify the differences in � 0.05 level of significance. To analyze spatial and temporal distribution, we used the CR-Campeiro6 ® generating digital maps of population distribution of stink bugs. To analyze the fluctuation, graphics were elaborated through the Excel® Software. Was quantified the populations of Euschistus heros (Fabricius, 1798), Dichelops furcatus (Fabricius, 1775), Piezodorus guildinii (Westwood, 1837), Nezara viridula (Linnaeus, 1758) and Edessa meditabunda (Fabricius, 1794). During the two years of study, E. heros and D. furcatus was the species most frequent in soybeans. D. furcatus is more common in corn, wheat and oats. P. guildinii occurs frequently in soybeans. Populations of N. viridula and E. meditabunda are less frequent. In the offseason, the bugs shelter in the trash, weeds, wheat, oats, turnip and migrate to the edge of forest vegetation and wetland. Populations of stink occur more frequently in soybean at stage R7.1 and R9, corn in summer and winter grasses. The location of the beginning of planting determines the distribution of the population. Areas sown late have high immigrant populations of bugs crop more developed or already picked. The occurrence, spatial-temporal distribution and population dynamics of stink bugs vary each year, influenced by soybeans, corn, wheat, oat, turnip, the crop successions, culture adjacent, alternative host plant, trash, weeds and management operations. / Os percevejos pentatomídeos são pragas de soja, milho, trigo e outras culturas. Economicamente, seu manejo é fundamental e o conhecimento do comportamento de suas populações é necessário para planejar medidas de ação eficientes. O objetivo desta pesquisa foi verificar a ocorrência, distribuição espaço-temporal e flutuação da população de espécies de percevejos, nas sucessões de cultivos e áreas adjacentes. O estudo foi realizado entre 12/2007 e 11/2009 no município de Jóia, RS, Brasil, em uma área agrícola comercial de 162ha com sistema de plantio direto e irrigação via pivô central (92ha) e áreas adjacentes (70ha). No primeiro ano de estudo, safra 2007/08, 41ha do pivô foi cultivado com soja [Glycine max (L.) Merril] e 51ha, com milho (Zea mays L.); já na entressafra de 2008, 41ha com aveia preta (Avena strigosa Schreb) associada com nabo forrageiro (Raphanus sativus L.) em sucessão à cultura de soja e 51ha com aveia preta na palhada do milho. No segundo ano, safra 2008/09, foi cultivada soja na totalidade da área do pivô (92ha) e áreas adjacentes (70ha). Já na entressafra 2009, foi cultivada aveia branca (Avena sativa L.) e preta em sucessão à soja e trigo (Triticum aestivum L.) nas áreas adjacentes do pivô. Através do programa CR-Campeiro 6® foi gerado um mapa temático da área de pesquisa e dividida em grade regular de 63 células de 2,5ha e seus centros constituíram-se nos pontos amostrais. Os pontos foram localizados com sistema de posicionamento global (GPS). Foram realizadas amostragens quinzenalmente em 2m², nas culturas, vegetação, palhada, restos de culturas e superfície do solo. Em planilha de campo anotou-se o número de percevejos adultos e ninfas a partir do segundo ínstar. As espécies foram confirmadas no laboratório de Manejo Integrado de Pragas (LabMIP). Para analisar a ocorrência populacional foram utilizadas séries estatísticas do tipo geográfica-temporal, elaborando-se tabelas de distribuição de frequências da população para cada cultura do pivô, áreas adjacentes e locais de refúgio. Os dados foram submetidos à análise estatística através do programa BioEstat 5®. Aplicou-se o teste binomial de probabilidade entre as populações de percevejos nas culturas e áreas adjacentes para verificar diferenças em nível de 5% de significância. Para analisar distribuição espaço-temporal utilizou-se o programa geoestatístico CR-Campeiro6® gerando mapas digitais de distribuição da população de percevejos. Para analisar a flutuação populacional, foram elaborados gráficos através do programa Excel®. Foram estudadas as populações de Euschistus heros (Fabricius, 1798), Dichelops furcatus (Fabricius, 1775), Piezodorus guildinii (Westwood, 1837), Nezara viridula (Linnaeus, 1758) e Edessa meditabunda (Fabricius, 1794). As espécies de maior ocorrência na safra foram E. heros e D. furcatus, concentrando-se na soja. D. furcatus é mais frequente nas culturas de milho, trigo e aveia. P. guildinii, ocorre com maior frequência na soja. Populações de N. viridula e E. meditabunda são menos freqüentes. Na entressafra, os percevejos abrigam-se na palhada, plantas espontâneas, trigo, aveia, nabo forrageiro e migram para vegetações de borda de mato e banhado. As populações de pentatomídeos ocorrem com maior frequência na cultura de soja nos estádios R7.1 e R9, no milho no verão e em gramíneas no inverno. O local de início do plantio determina a distribuição da população de percevejos. Áreas semeadas tardiamente apresentam elevadas populações de percevejos emigrantes de cultivos mais desenvolvidos ou já colhidos. A ocorrência, distribuição espaço-temporal e flutuação populacional de percevejos variam anualmente, influenciadas pelas sucessões de culturas de soja, milho, trigo, aveia, nabo forrageiro, cultura adjacente, vegetação de refúgio, palhada, plantas daninhas e operações de manejo.
93

Estrutura e dinâmica populacional de Eschweilera ovata (Cambess.) Miers (Lecythidaceae) em fragmentos de Mata Atlântica / Strucuture and population dynamics of Eschweilera ovate (Cambess.) Miers (Lecythidaceae) in fragments of Atlantic Rain Forest

Cavalcanti, Airton de Deus Cysneiros, 1980- 12 May 2012 (has links)
Orientador: Flavio Antonio Maes dos Santos / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T02:00:48Z (GMT). No. of bitstreams: 1 Cavalcanti_AirtondeDeusCysneiros_D.pdf: 6557195 bytes, checksum: beab670108442a3cbaed85443f577345 (MD5) Previous issue date: 2012 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Doutorado / Biologia Vegetal / Doutor em Biologia Vegetal
94

CHARACTERIZATION OF THE ABA PEAKING TYPE DYNAMIC DURING LONG TERM DROUGHT

Joel Abdel Mercado Reyes (11824124) 19 December 2021 (has links)
Plants rely on diverse strategies to regulate water loss during drought. The phytohormone abscisic acid (ABA) is a critical mediator of stomatal closure during water stress in seed plants. Studies in conifers identified diverging strategies in long-term drought of ABA-mediated dynamics, particularly a peaking type dynamic during long term drought in some conifers. Few studies have reported this dynamic in angiosperms, and no study has revealed the mechanism driving declines in ABA levels as drought progresses in peaking type species. To understand peaking type dynamics, we exposed the model peaking type gymnosperm species <i>Callitris rhomboidea</i> and the highly drought resistant evergreen angiosperm <i>Umbellularia californica</i> to controlled long-term drought. We measured leaf water potentials (Ψ<sub>l</sub>), stomatal conductance, ABA and the ABA catabolite phaseic acid (PA) levels in potted plants during a prolonged but non-fatal drought. We aimed to determine which of three potential drivers of peaking type dynamic were responsible for this response: (1) increased catabolism of ABA into PA at a threshold Ψ<sub>l</sub> , (2) ABA export from the leaf is enhanced under drought, and (3) ABA biosynthesis ceases at a threshold Ψ<sub>l</sub>. During long term drought, the evergreen angiosperm species <i>U. californica</i> demonstrated peaking type ABA dynamics like gymnosperms. In both species, PA levels did not increase significantly, in fact, PA levels tracked ABA levels, suggesting that ABA catabolism to PA may be a function of ABA levels. Girdling experiments to determine whether export from the leaf drove declines in ABA levels demonstrated that of the majority of ABA was likely converted to ABA glucose ester (ABA-GE), an inactive storage form of ABA, and exported from shoots during drought. Finally, by rapidly dehydrating branched collected at different timepoints during long-term drought we were able to determine that ABA biosynthesis is completely down regulated in leaves that have been dehydrated beyond leaf turgor loss point. The decline in ABA levels in peaking type species appears conserved across seed plants and is mediated by high export rates in the form of ABA-GE. Future work should assess a more diverse selection of species as well as study long-term drought in less tolerant species to test whether ABA biosynthesis is deactivated in all species once Ψ<sub>l </sub>declines below turgor loss point.
95

Predatoriska fåglars effekt på populationsdynamiken hos amfibier

Melander, Lovisa January 2021 (has links)
The global amphibian population is rapidly declining. Although many threats that affect amphibians are known, there are many contributing factors which are not fully understood. For adult amphibians, the largest part of the mortality comes from predation. We know of many predators which prey upon amphibians, but to what extent they affect the populations has not been subject to much investigation. Neither has the effects of specific taxa or species of predators. Birds are reputed amphibian-eaters, and they often occur in the same habitats. Both birds and amphibians often select for wetlands and other water bodies with high biodiversity, that often support a high diversity and/or density of birds as well as amphibians. The fact that a prey might flourish in an area that one of its strongest predators also inhabits might seem controversial. Especially when taking into account that it is often the density of predators that best explains the population growth of prey species. In this review, I investigate what effects large amounts of birds might have on amphibian populations as a result of their predation on adults. I consider how the effects might differ with high vs low densities of both prey and predator, and whether an eventual effect might impact the survival of a metapopulation differently depending on its size and spatial distribution. As an example of a habitat where both bird and amphibian species occur in large numbers, I use Trönninge ängar - a bird conservation area just outside the city of Halmstad, where populations of both amphibians and birds have been increasing over the last years. My results show that high densities of predatory birds in such communities could potentially cause declines in amphibian populations, but that this impact is softened when the population is more widely distributed in the area. There are also possibilities that birds do not only affect amphibians by predation, but also might facilitate their distribution by reducing other predators. Thus, bird predation in itself might not be a sufficient predictor for their effect on amphibian populations, as the relationship might be more complex than simple predator-prey interactions.
96

Srovnání reprodukčních parametrů středoevropských populací kriticky ohroženého druhu motýla - okáče skalního (Chazara briseis) / Comparison of reproductive parameters of Central European populations of the critically endangered Hermit butterfly (Chazara briseis)

Štochlová, Tereza January 2021 (has links)
The Hermit butterfly Chazara briseis is a species from the family Nymphalidae, inhabiting mostly short-stemmed dry steppes. In Central Europe, it is critically endangered. It is therefore currently the subject of many conservation activities, including reintroductions. In such translocations of individuals, it is important that the native and source populations be as closely related as possible in all respects. Therefore, individuals of two forms of this species, Ch. briseis pannonica (Austrian population) and Ch. briseis bataia (Czech population) were bred and their reproductive characteristics were recorded and the differences between the two forms were observed. During two seasons 5 Austrian and 8 Czech females were successfully bred. The Austrian and Czech populations differed mainly in the timing of adult hatching and the beginning of the laying of eggs by females - Austrian individuals are phenologically shifted to one week to 14 days earlier. Individual populations of the same species may also differ from each other in the presence of Wolbachia pipientis. This bacterium can affect the sex ratio in a population as well as the reproduction behavior of individuals. There was a suspicion of its presence in the Czech population. Therefore, a part of the Czech population was treated with...
97

The Population Ecology of a Headstart Supplemented Population of Diamondback Terrapins (Malaclemys terrapin) at the Poplar Island Environmental Restoration Project in the Middle Chesapeake Bay

Smeenk, Nicholas A. 05 August 2010 (has links)
No description available.
98

BLANDING’S TURTLE OCCUPANCY AND ABUNDANCE IN SOUTHERN MICHIGAN AND OHIO

Daniel James Earl (13943547) 13 October 2022 (has links)
<p>  </p> <p>Blanding’s Turtle populations face direct threats to their survival. To help protect populations, habitats that can best support Blanding’s Turtle populations need to be identified across their range. Blanding’s Turtles have been a difficult to detect species and may be present at a site even if not detected during targeted surveys. Additionally, Blanding’s Turtles may be present at a site but may have little to no recruitment so additional measures of site suitability beyond species presence are needed to determine more suitable or higher quality habitats. In my research, I attempt to determine suitability of sites for Blanding’s Turtles across Michigan and Ohio using data collected from rapid assessment protocols fit into single season occupancy models with wetland and upland landcover types as co-variates of occupancy. To further determine the suitability of sites based on these data, I created single season occupancy models for juvenile Blanding’s Turtles and used N-mixture abundance modelling to determine relative abundance of Blanding’s Turtles at a site using the same landcovers as covariates of occupancy and abundance. Both modelling frameworks also allowed me to include detection covariates that could increase Blanding’s Turtle detection in future surveys. </p> <p>Detection was largely influenced by Julian date with the highest probability of detection occurring from mid-May through late June. Length of trapping surveys was also found to influence Blanding’s Turtle detection with a substantial decrease in daily trap capture rates by the fourth trap night of a survey. Michigan occupancy and abundance models found that the most suitable sites in Michigan would have high percentages of high-quality upland forest and woody wetland landcovers, with the percentage of open water supporting the occupancy of turtles but having no discernable effect on abundance. Total upland forest also significantly increased the probability of juvenile occupancy in Michigan. In Michigan, I also observed that survey method can greatly influence the estimates of occupancy and abundance, and I determined that visual surveys cannot accurately determine these estimates. The heavily disturbed nature of Ohio’s landscape took away from the predictive power of landcovers used in my research for Blanding’s Turtle occupancy and abundance. The vast difference between occupied habitats in Michigan and Ohio also takes away from the predictive power of the regional level model and relative abundance of Blanding’s Turtle populations cannot be accurately determined at this scale using the spatial covariates I included. However, total undisturbed forest and total wetland proved to be positive covariates of Blanding’s Turtle abundance and occupancy for adult and juvenile turtles across both states, but the habitats used in each state vary greatly so future conservation decisions should be made on the state level as largest spatial scale. Using my models for Michigan suitable sites can be determined within the state and compare relative abundance between sites to determine healthier populations. For future analysis in Ohio, different, smaller scales spatial covariates should be used to explain differences in occupancy and abundance between sites.</p>
99

Population Dynamics of Piping Plovers (Charadrius melodus) on the Missouri River

Catlin, Daniel H. 09 June 2009 (has links)
Habitat loss and predation are threatening many shorebird populations worldwide. While habitat preservation often is preferable, sometimes habitat needs to be restored or created in order to stave off immediate declines. The Great Plains population of piping plovers (Charadrius melodus) was listed as threatened in 1986, and habitat loss and predation appear to be limiting the growth of this population. On the Missouri River, piping plovers nest on sandbars, but the damming of the mainstem of the Missouri in the mid-twentieth century reduced the natural capacity of the Missouri River to create sandbar habitat. In 2004, the United States Army Corps of Engineers (USACE) implemented a habitat creation project on the Gavins Point Reach of the Missouri River (stretch of river immediately downriver from the Gavins Point Dam) in an effort to promote recovery of piping plovers and the endangered least tern (Sternula antillarum). The USACE built 3 sandbars in 2004 – 2005 and built another sandbar on Lewis and Clark Lake in 2007. We studied the population dynamics of piping plovers in relationship to this newly engineered habitat. We monitored 623 nests on 16 sandbar complexes, to evaluate habitat selection, determine the factors affecting nesting success, and compare nesting success between natural and engineered habitat. From these 623 nests, we banded 357 adults and 685 chicks to investigate the factors affecting adult and juvenile survival. We used a logistic-exposure model to calculate nest survival. Adult and juvenile survival was calculated using Cormack-Jolly-Seber based models in Program MARK. We used the estimates from these studies to create a matrix population model for piping plovers nesting on the Gavins Point Reach. We used this model to predict the effects of engineered habitat on the population growth rate. Piping plovers selected for engineered sandbars and against natural and natural/modified habitats. Daily survival rate (DSR) on engineered habitats was significantly higher than on natural or natural modified habitats (log odds: 2.71, 95% CI: 1.20 – 6.08). Predator exclosures around nests did not affect DSR after controlling for the effects of date, nest age, and clutch size. Piping plover juvenile survival to recruitment was negatively related to nesting density on the relatively densely populated engineered sandbars. On the less dense natural sandbars, survival to recruitment was positively correlated with density. Adult survival did not appear to be related to density within our study. Movement within the study area was related also to density. Juveniles from densely populated engineered sandbars were more likely to leave engineered habitat to nest on natural sandbars than were juveniles hatched on less densely populated engineered sandbars. Movements among sandbars by breeding adults suggested that adults preferred engineered habitat. It is possible that juveniles moved to natural habitats because they were unable to compete with adults for the more desirable engineered habitats. Adults and juveniles emigrated from the study area at a higher rate after the 2006 breeding season, a year when water discharge was higher, nesting densities were higher, and reproductive success was lower (as a result of predation) than in the other years. Deterministic modeling suggested that engineered habitat significantly increased population growth. Decreased productivity over time and associated predicted negative population growth suggest that the amount of engineered habitat created was inadequate to sustain population growth, and/or that relatively high water discharge and nesting densities coupled with low reproductive rates and high emigration rates could lead to rapid declines in the plover population. Continued research is needed to determine the effects of these factors on long-term population growth. Our results suggest that habitat creation could be a viable short-term solution to population declines in shorebird populations limited by habitat loss, but high densities and increased predation associated with habitat creation indicate that other, long-term solutions may be required. / Ph. D.
100

Status taxonômico de Callichirus major (Say, 1818) sensu lato (Crustacea, Decapoda, Axiidea, Callianassidae) da costa brasileira: taxonomia, sistemática molecular, biologia populacional e reprodutiva / Taxonomic status of Callichirus major (Say, 1818) sensu lato (Crustacea, Decapoda, Axiidea, Callianassidae) from the Brazilian coast: taxonomy, molecular systematics, population biology and reproductive biology

Peiró, Douglas Fernando 21 November 2012 (has links)
Esta tese trata, primariamente, da definição do status taxonômico do amplamente conhecido corrupto de praia ou ghost shrimp Callichirus major (Say, 1818) sensu lato (Decapoda, Axiidea, Callianassidae) ocorrente na costa brasileira (Capítulo I). A definição deste táxon era um tanto incerta até o momento, levando-se em conta a grande similaridade morfológica entre as espécies que compõem o complexo C. major. Alguns estudos morfológicos, moleculares e larvais foram realizados anteriormente de forma isolada, e sem uma abrangência ao longo de toda sua área de distribuição. Entretanto, nenhum destes estudos foi conclusivo quanto à validade ou não do nome C. major ser aplicado à espécie brasileira. De forma complementar, esta tese objetivou o estudo sobre o investimento reprodutivo e sobre a ecologia populacional de uma de suas populações do litoral norte do Estado de São Paulo (Capítulos II e III, respectivamente). Os resultados desta tese são apresentados em capítulos separados, devido ao fato deles tratarem de assuntos distintos envolvendo a taxonomia/sistemática molecular, biologia reprodutiva e a ecologia populacional da espécie. Cada capítulo contém suas próprias sessões: Resumo, Introdução, Material & Métodos, Resultados, Discussão e Referências. Também, cada capítulo apresentado nesta tese é equivalente a um artigo submetido ou a ser submetido a revistas científicas e encontram-se formatados de acordo com as normas das revistas escolhidas. / This thesis is primarily about the taxonomic status of the ghost shrimp Callichirus major (Say, 1818) sensu lato (Decapoda, Axiidea, Callianassidae) from Brazilian coastlines (Chapter I). The taxonomic status of C. major complex was uncertain until now, due to the very large range of distribution and morphological characters shared among species. Some morphologic, molecular and larval studies were made in isolated perspective and without a distribution range overview before that. None of them were conclusive about the validity to name C. major been applied for the Brazilian species. In a complementary way, this thesis aimed the reproductive output and the population ecology of the species in a sandy beach in the North Shore, State of São Paulo, Brazil (Chapters II and III, respectively). The results of this thesis were presented in distinct chapters due to different approaches related to taxonomy/systematics, reproductive biology and population ecology of this species. Each chapter has its own sections: Abstract, Introduction, Material and Methods, Results, Discussion and References. Those chapters are equivalent to an article submitted or to be submitted to scientific journals, and are formatted according to the author guidelines of each journal.

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