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Using Anthropogenic Parameters at Multiple Scales to Inform Conservation and Management of a Large CarnivoreWynn-Grant, Rae Jackson January 2015 (has links)
Human influence on the environment is becoming increasingly pervasive across the globe, and can drastically impact ecological patterns and processes. For many terrestrial wildlife species, human influence can fragment critical habitat, increase mortality, and threaten habitat connectivity and ultimately the persistence of wildlife populations. This dissertation aims to use multiple conservation ecology methods and tools to test the impact of human influence on the population dynamics of a large carnivore in a human-dominated landscape.
To assess the impact of human activity on carnivore ecology, a series of empirical studies were conducted on a small population of American black bear (Ursus americanus) in the Western Great Basin, USA. A long-term dataset including geographic locations of animal habitat choices as well as mortality locations were used in multiple statistical models that tested the response of black bears to human activity. These analyses were conducted at multiple spatial and temporal resolutions to reveal nuances potentially overlooked if analyses were limited to a single resolution.
Individual studies, presented as dissertation chapters, examine the relationships between human activity and carnivore ecology. Collectively, the results of these studies find black bear ecology to be highly sensitive to the magnitude and spatial composition of human activity in the Lake Tahoe Basin, observable at both coarse and fine spatial resolutions. The results presented in this study on the influence of human activity on large carnivore population dynamics allow for a more thorough understanding of the various ways common conservation ecology methods and tools can be used to evaluate human-wildlife relationships.
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Epitélio intestinal de juvenis de pacu (Piaractus Mesopotamicus, Holmberg 1887) e dourado (Salminus brasiliensis, Cuvier 1816) alimentados com dieta contendo colostro bovino liofilizado / Intestinal epithelium of pacu (Piaractus mesopotamicus, Holmberg 1887) and dourado (Salminus brasiliensis, Cuvier 1816) juveniles fed diet containing lyophilized bovine colostrumCruz, Thaline Maira Pachelli da 11 December 2013 (has links)
O objetivo deste trabalho foi avaliar o efeito do colostro bovino liofilizado (CBL), utilizado como fonte parcial da dieta protéica, sobre as características histológicas do epitélio intestinal de juvenis de pacu (Piaractus mesopotamicus) e dourado (Salminus brasiliensis). Os juvenis foram distribuídos num delineamento experimental inteiramente casualizado em esquema fatorial 3x2. Foram utilizadas dietas com três níveis de inclusão de CBL (0%, 10% e 20%) e dois períodos experimentais (30 e 60 dias), oferecidas duas vezes ao dia até a saciedade aparente. Para o estudo histológico, o intestino foi dividido em três segmentos, S1, S2 e reto para pacu e S1, S2 e intestino posterior para dourado. Foram avaliadas a espessura da camada muscular; o volume parcial da mucosa absortiva (Vv); o número das células caliciformes contendo mucinas ácidas e neutras e totais, e os subtipos ácidas - sialomucinas e sufomucinas. Nos juvenis de pacu, a inclusão de 20% de CBL alterou a distribuição das células caliciformes contendo as mucinas ácidas, neutras e totais, os subtipos sialomucinas e sulfomucinas, e a espessura da camada muscular, enquanto o Vv foi afetado apenas pelo período experimental. Nos juvenis de dourados, efeito de período experimental foi observado para células caliciformes contendo mucinas ácidas, neutras e totais e os subtipos sialomucinas e sulfomucinas, espessura da camada muscular e Vv. A adição de 10% de CBL afetou apenas o Vv no segmento S1. Considerando os aspectos avaliados no presente estudo, a presença do colostro bovino liofilizado na dieta influenciou, no período estudado, as características histológicas entéricas de juvenis de pacu, enquanto que nos juvenis de dourado influencia desta secreção láctea não foi observada. / The aim of this study was to evaluate the effect of lyophilized bovine colostrum (LBC), used as partial source of protein in the diet, on the histological characteristics of the intestinal epithelium of juvenile pacu (Piaractus mesopotamicus) and juvenile dourado (Salminus brasiliensis). Juveniles were distributed in a completely randomized design in a factorial scheme 3x2. Three diets were used with different levels of LBC inclusion (0%, 10% and 20%) and two experimental periods (30 and 60 days) offered twice daily until apparent satiation. For the histological study, the intestine was divided into three segments, S1, S2 and rectum to the pacu and S1, S2 and posterior intestine to the dourado. The muscle layer thickness; the mucosal absorptive volume (Vv); the number of goblet cells containing acidic and neutral mucins and the acidic subtypes - sialomucin and sulphomucin were evaluated. In juvenile pacu, the inclusion of 20% of LBC changed the distribution of goblet cells containing acidic, neutral and total mucins, the subtypes sialomucins and sulphomucins, and the thickness of the muscle layer, while the Vv was affected only by the experimental period. In juvenile dourado, effect of experimental period was observed for goblet cells containing acidic, neutral and total mucins and subtypes sialomucins, sulphomucins, thickness of muscle layer and Vv. The addition of 10% of LBC affected only Vv in the segment S1. Considering the aspects studied, the presence of lyophilized bovine colostrum in the diet influenced, in the period studied, the enteric histological characteristics of juvenile pacu, while the juvenile dourado influence of this lacteal secretion was not observed.
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Os medios e grandes mamiferos de mosaicos em areas de reflorestamentos no Centro-Oeste paulista / The medium and large mammals of mosaics in reflorestations areas in the São Paulo center-westMendonça, Leonardo Siqueira 14 August 2018 (has links)
Orientador: Eleonore Zulnara Freire Setz / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-14T15:10:35Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: A riqueza, composição e abundância da mastofauna de médio e grande porte, em duas áreas de reflorestamentos comerciais da Duraflora S/A, no centro-oeste do estado de São Paulo, foram estudadas entre 2005 e 2007. O objetivo deste estudo foi entender como a fauna de mamíferos utiliza áreas de reflorestamento e o potencial de mosaicos com predominância de monocultura madeireira para a sobrevivência da onça-parda e a conservação da mastofauna silvestre. Estudei dois mosaicos de reflorestamentos de Pinus spp. e Eucalyptus spp., um em Agudos e outro em Lençóis Paulista. O primeiro possui 16.200 ha e a
formação predominante dos remanescentes de vegetação nativa é Cerrado. O mosaico de Lençóis Paulista possui 23.085 ha, sendo a principal formação remanescente a Floresta Atlântica Estacional Semidecídua. Em 2005 percorri um total de 303 km nas estradas de terra do mosaico em Agudos e 346 km em Lençóis Paulista, realizando censos de vestígios e georreferenciando-os com um GPS, além de coletar fezes de carnívoros para determinar as suas dietas. Em 2006 e 2007 utilizei parcelas de areia para estimar tanto a abundância, quanto a diversidade de mamíferos de médio e grande porte para futura compararação com
outros estudos. Através de entrevistas com funcionários e pesquisa no acervo da empresa, complementei a lista de espécies presentes nos mosaicos. O esforço amostral de parcelas em Agudos foi de 1000 parcelas-noite e em Lençóis Paulista 950. O número de fezes analisadas foi 83 para Agudos e 38 para Lençóis Paulista. Embora estivessem presentes as mesmas dez ordens de mamíferos, em Agudos houve a presença de 31 espécies de 16 famílias, e em Lençóis Paulista 39 espécies de 20 famílias. Apesar do maior numero de registros de Agudos e da menor presença de espécies sensíveis à perda de habitat, principalmente primatas, os índices de similaridade qualitativa de Sorensen (0,69), e quantitativa de Morisita-Horn (0,623) indicaram considerável semelhança entre as áreas. Já o índice de diversidade de Shannon-Wiener, para os mamíferos registrados pelas parcelas nos reflorestamentos, foi significativamente maior (t= 2,07; gl= 67; p<0,02) para Agudos (H10'= 1,12), que para Lençóis Paulista (H10'= 0,99). Porém, em Agudos, as dietas das espécies parecem ser mais especializadas, sugerindo que Agudos possua menor diversidade de espécies de presas, ou maior abundância. Os animais de médio e grande porte mais registrados foram tatus, veados e canídeos. Lagomorfos, tamanduás e procionídeos também estiveram presentes nos reflorestamentos, assim como pequenos roedores não restritos à Floresta Atlântica. Marsupiais também foram freqüentes, ao contrário de espécies que dependem da disponibilidade de frutos como paca, cutia e cateto. Os felídeos apresentaram baixa abundância nos mosaicos, assim como em áreas naturais. A maioria dos mamíferos de médio e grande porte transita pelas áreas de reflorestamento, não ficando restritas às áreas de conservação. Mesmo sendo áreas particulares monitoradas, a fauna está sujeita à atividade de caça e à presença de cães domésticos. O ratão-do-banhado (Myocastor coypus) e o lebrão (Lepus europaeus), espécies exóticas, também foram registrados nos mosaicos, embora o ratão, assim como roedores cosmopolitas, não tenham sido registrados nas análises de fezes dos carnívoros. / Abstract: Richness, composition and abundance of medium and large mammals were studied in two commercial reforestation Duraflora's areas in Northwest of São Paulo state between 2005 and 2007. The goal of this research was to understand how the mammals use the reforestations and the potential of landscape mosaics dominated by timber monoculture for the conservation of the puma and other wild mammals. The area of the Agudos' mosaic is 16200 ha, dominated by Cerrado forest in conservated areas while Lençóis Paulista's mosaic has 23085 ha, dominated by Semidecidual Atlantic Forest. During the 2005 I rode 303 Km and 346 Km in Agudos and Lençóis Paulista land-roads, doing the traces censuses, marking them with GPS and collecting carnivorous scats to point out these species diet. To estimate abundance and diversity, in 2006 and 2007 I used scent station, after I compared with the results with another same method researches. By personal interviews and research in company's library I added to the list of mammals another studied species. The Agudos' scent stations sampling effort was 1000 scent night-station, therefore Lençóis Paulista's was 950 scent night-stations. The number of feaces sampling was 83 in Agudos and 38 in Lençóis Paulista. Although the same ten mammal's orders have been present, there were 34 species from 19 families in Agudos and 38 species from 21 families in Lençóis Paulista. Compared with Lençóis Paulista, the total records was greater in Agudos, but smaller for the rare and habitat loss sensible species, mainly primates. Even if that differences, the Sorensen (0,69) and Morisita-Horn (0,623) index pointed high similarity between areas. The Shannon-Wiener diversity index about scent stations recorded mammals in Agudos's reforestation was high. In Agudos the species' diet seems to be closer than Lençóis Paulista. It suggests that Lençóis Paulista has a higher number of prey species or lower abundance of each one. The most recorded middle and big size mammals were armadillos, deers and canideos. Lagomorphs, anteaters and some procyonideos also seem to walk the reforestations, like the small rodents no restricted to the Atlantic Forest. Marsupials also appeared commonly unlike habitat-dependent species agouti, paca and peccary. Like in natural habitats felids presented low abundance. The most part of the medium and big size terrestrial mammals that use reforestation areas haven't been restricted to the conservation areas. Even if these private areas have being monitored, the fauna also suffers with hunting pressure and domestic dog presence as recorded in some situations. The presence of exotic species of nutria and European hare was also recorded. The nutria, as well as the cosmopolitan rodents, weren't recorded at carnivorous feaces. / Mestrado / Ecologia / Mestre em Ecologia
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Variação de coloração em Drosera hirtella (Droseraceae) e sua relação com variáveis ambientais / Color variation in Drosera hirtella (Droseraceae) and its relation to environmental variablesSpolon, Melissa Gallo, 1984- 22 August 2018 (has links)
Orientadores: João Vasconcellos Neto, Gustavo Quevedo Romero / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T05:42:43Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: Plantas carnívoras, além de autotróficas também capturam presas, o que lhes permite ocupar ambientes pobres em nutrientes. Na região da Serra do Cipó ¿ MG, em uma área de campos rupestres, encontra-se com freqüência a espécie de planta carnívora Drosera hirtella A. St.-Hil. var. hirtella (D. hirtella), que apresenta variação na coloração das folhas e tricomas, havendo plantas desde totalmente verdes até totalmente vermelhas. Essa variação natural permitiu a realização de experimentos para testar as quatro hipóteses que serão descritas nos parágrafos a seguir. Para a primeira hipótese, esperava-se que D. hirtella mais expostas ao sol fossem mais frequentemente vermelhas, enquanto as menos expostas fossem mais frequentemente verdes, sendo a cor vermelha provavelmente uma forma de proteção contra a fotodegradação. Esta hipótese foi corroborada pelo primeiro experimento, que mostrou forte relação da cor de D. hirtella com o nível de exposição solar além de uma grande plasticidade da coloração dessa espécie de acordo com as condições de luminosidade. A segunda hipótese de trabalho foi parcialmente corroborada, pois se esperava que D. hirtella em áreas de solos mais pobres (menor concentração de nitrogênio) fossem mais frequentemente vermelhas, enquanto que D. hirtella em áreas de solos mais férteis (maior concentração de nitrogênio) fossem mais frequentemente verdes. O segundo experimento mostrou que os nutrientes disponíveis podem interferir na coloração da planta. A cor poderia ser assim uma resposta à deficiência de nutrientes disponíveis no solo, mas não necessariamente à deficiência de nitrogênio. A terceira hipótese, em que se esperava que D. hirtella de cor vermelha atraíssem mais insetos do que as de cor verde (um maior número de presas capturadas seria importante em solos pobres em nitrogênio), foram parcialmente corroborada pelos terceiro e quarto experimentos. A atratividade da forma vermelha de D. hirtella foi verificada, no entanto o segundo e o quinto experimentos mostraram que o nitrogênio presente no solo pode não estar interferindo diretamente na cor ou no número de presas capturadas. No terceiro experimento foi possível verificar que plantas vermelhas capturaram mais presas do que plantas verdes e plantas intermediárias. No entanto não ficou claro se a maior taxa de captura foi devida à coloração ou à quantidade de mucilagem, pois plantas vermelhas apresentaram mais tricomas funcionais. O quarto experimento mostrou que simulacros de plantas vermelhas capturaram mais presas em potencial do que simulacros de plantas verdes. Por fim, o quinto experimento não corroborou as predições da quarta hipótese em que se esperava que D. hirtella vermelhas, por capturarem mais presas, deveriam acumular mais 15N em seus tecidos do que as verdes; enquanto os tecidos das plantas verdes teriam mais nitrogênio total do que os tecidos das plantas vermelhas - por estarem em solos supostamente mais ricos em nitrogênio total. A única relação significativa foi à inesperada menor quantidade de 15N (d 15N) em plantas vermelhas. No entanto os resultados também sugerem que plantas vermelhas possam estar obtendo um ganho proporcionalmente maior de d15N, sugerindo que plantas verdes e vermelhas possam utilizar formas diferentes de processar esse isótopo / Abstract: Carnivorous plants are autotrophic organisms that also capture prey, allowing them to occupy nutrient-deficient habitats. In an area of rupestrian fields in the region of Serra do Cipó ¿ MG, the species of carnivorous plant Drosera hirtella A. St.-Hil. var. hirtella (D. hirtella) is frequently observed displaying color variation of its leaves and trichomes, which goes from totally green in some plants until completely red in others. This color variation has led to the experimental tests to examine the validity of four hypotheses. For the first hypothesis we expected that plants of D. hirtella more exposed to the sun were more often red whereas the least exposed plants were more frequently green. The red color is probably a form of protection against photodegradation. The first experiment showed a strong correlation between color of D. hirtella plants with the level of sun exposure and a great plasticity of this species color in accordance with light conditions. The second hypothesis was only partially supported as we expected that D. hirtella in areas of poor soils (less nitrogen) were most often red, whereas D. hirtella in areas of more fertile soils (more nitrogen) should be most often green. The second experiment showed that the availability of nutrients might also influence plant coloration. The color variation could be a general response to nutrient-deficient soils, but not necessarily a response to nitrogen deficiency. The third hypothesis, in which we expected that red plants would attract more insects than green plants (because a greater number of captured preys would be more important in low nitrogen soils), was partially supported by third and fourth experiments. The attractiveness of the red form of D. hirtella was confirmed, but the second and the fifth experiments showed that the nitrogen present in the soil may be not directly interfering in color and/or prey capture. In the third experiment we found that red plants caught more prey than green plants and intermediate plants. However it was unclear whether the higher catch rate was due to color or to the quantity of mucilage, because red plants showed more functional trichomes than green plants. The simulations of the fourth experimental block showed that the simulacra of red plants caught more potential prey than simulacra of green plants. Finally, as mentioned above, the fifth experiment did not exhibit the expected results of the fourth hypothesis, where it was expected that the red form of D. hirtella, by capturing more prey, should accumulate more 15N in their tissues than the green one; whereas the green plants tissues - supposedly living in soils richer in total nitrogen - should have more total nitrogen than the red plants tissues. The only significant relationship was the unexpected smaller d 15N in red plants. However the results also suggest that red plants may have a proportionally greater gain of d 15N, suggesting that green and red plants may use different ways of processing this isotope / Mestrado / Ecologia / Mestre em Ecologia
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Diversidade genética de microrganismos presentes em utrículos da planta carnívora Utricularia foliosa (Lentibulariaceae). / Microbial diversity inside the utricles of carnivorous plant Utricularia foliosa (Lentibulariaceae).Carolina Bertini da Silva 22 October 2013 (has links)
O conhecimento da associação entre plantas carnívoras e a comunidade bacteriana pode mostrar uma diversidade ainda não conhecida, além de proporcionar um melhor entendimento dos mecanismos envolvidos na interação de ambas. O objetivo deste trabalho foi avaliar a diversidade microbiana presente em utrículos de Utricularia foliosa através da análise de bibliotecas do gene 16S rRNA obtida por pirosequenciamento. Os resultados indicam que no ponto 1, Proteobacteria (58%), Firmicutes (11%), Cyanobacteria (11%), Acidobacteria (7%), Verrucomicrobia (5%), Actinobacteria (3%) Chlamidiae (2%) e Bacteroidetes (1%) foram os grupos dominantes. Já no ponto 2 houve uma maior presença de Eukaryota (51%), sendo que os grupos mais presentes foram Streptophyta (88%), Bacillariophyta (7%) e Chlorophyta (2%). A grande presença de algas encontradas pode estar relacionada à disponibilidade de nutrientes nos utrículos e gerar um acréscimo de carbono e nitrogênio à cadeia alimentar no interior da armadilha. / Knowledge of the association between carnivorous plants and the bacterial community can show a diversity not yet known, and provide a better understanding of the mechanisms involved in the interaction of both.The aim of this study was to evaluate the microbial diversity present in utricles of Utricularia foliosa and evaluate the effect of plant growth site in this diversity. For this the 16S rRNA gene library was sequenced by pyrosequencing (454-Roche). The results indicate that in point 1, the dominants groups were composed by Proteobacteria (58%), Firmicutes (11%), Cyanobacteria (11%), Acidobacteria (7%), Verrucomicrobia (5% ) Actinobacteria (3%) Chlamidiae (2%) and Bacteroidetes (1%), while in the point 2, Eukaryota (51%), such as Streptophyta (88%), Bacillariophyta (7%) and Chlorophyta (2%) were dominant. The large presence of algae inside the utricles may be related to the availability of nutrients and increase the Carbon and nitrogen level inside the traps, allowing the growth of the plant and also the microbial community in this structures.
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Epitélio intestinal de juvenis de pacu (Piaractus Mesopotamicus, Holmberg 1887) e dourado (Salminus brasiliensis, Cuvier 1816) alimentados com dieta contendo colostro bovino liofilizado / Intestinal epithelium of pacu (Piaractus mesopotamicus, Holmberg 1887) and dourado (Salminus brasiliensis, Cuvier 1816) juveniles fed diet containing lyophilized bovine colostrumThaline Maira Pachelli da Cruz 11 December 2013 (has links)
O objetivo deste trabalho foi avaliar o efeito do colostro bovino liofilizado (CBL), utilizado como fonte parcial da dieta protéica, sobre as características histológicas do epitélio intestinal de juvenis de pacu (Piaractus mesopotamicus) e dourado (Salminus brasiliensis). Os juvenis foram distribuídos num delineamento experimental inteiramente casualizado em esquema fatorial 3x2. Foram utilizadas dietas com três níveis de inclusão de CBL (0%, 10% e 20%) e dois períodos experimentais (30 e 60 dias), oferecidas duas vezes ao dia até a saciedade aparente. Para o estudo histológico, o intestino foi dividido em três segmentos, S1, S2 e reto para pacu e S1, S2 e intestino posterior para dourado. Foram avaliadas a espessura da camada muscular; o volume parcial da mucosa absortiva (Vv); o número das células caliciformes contendo mucinas ácidas e neutras e totais, e os subtipos ácidas - sialomucinas e sufomucinas. Nos juvenis de pacu, a inclusão de 20% de CBL alterou a distribuição das células caliciformes contendo as mucinas ácidas, neutras e totais, os subtipos sialomucinas e sulfomucinas, e a espessura da camada muscular, enquanto o Vv foi afetado apenas pelo período experimental. Nos juvenis de dourados, efeito de período experimental foi observado para células caliciformes contendo mucinas ácidas, neutras e totais e os subtipos sialomucinas e sulfomucinas, espessura da camada muscular e Vv. A adição de 10% de CBL afetou apenas o Vv no segmento S1. Considerando os aspectos avaliados no presente estudo, a presença do colostro bovino liofilizado na dieta influenciou, no período estudado, as características histológicas entéricas de juvenis de pacu, enquanto que nos juvenis de dourado influencia desta secreção láctea não foi observada. / The aim of this study was to evaluate the effect of lyophilized bovine colostrum (LBC), used as partial source of protein in the diet, on the histological characteristics of the intestinal epithelium of juvenile pacu (Piaractus mesopotamicus) and juvenile dourado (Salminus brasiliensis). Juveniles were distributed in a completely randomized design in a factorial scheme 3x2. Three diets were used with different levels of LBC inclusion (0%, 10% and 20%) and two experimental periods (30 and 60 days) offered twice daily until apparent satiation. For the histological study, the intestine was divided into three segments, S1, S2 and rectum to the pacu and S1, S2 and posterior intestine to the dourado. The muscle layer thickness; the mucosal absorptive volume (Vv); the number of goblet cells containing acidic and neutral mucins and the acidic subtypes - sialomucin and sulphomucin were evaluated. In juvenile pacu, the inclusion of 20% of LBC changed the distribution of goblet cells containing acidic, neutral and total mucins, the subtypes sialomucins and sulphomucins, and the thickness of the muscle layer, while the Vv was affected only by the experimental period. In juvenile dourado, effect of experimental period was observed for goblet cells containing acidic, neutral and total mucins and subtypes sialomucins, sulphomucins, thickness of muscle layer and Vv. The addition of 10% of LBC affected only Vv in the segment S1. Considering the aspects studied, the presence of lyophilized bovine colostrum in the diet influenced, in the period studied, the enteric histological characteristics of juvenile pacu, while the juvenile dourado influence of this lacteal secretion was not observed.
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Following Darwin's footsteps using 'the most wonderful plants in the world' : the ecophysiological responses of the carnivorous plant Drosera rotundifolia to nitrogen availabilityCook, Joni L. January 2015 (has links)
Nitrogen (N) is an essential element to plants for growth, maintenance and reproduction, however most N does not exist in a form that is biologically available to plants. In order to maximise the acquisition and retention of N, plants have evolved a variety of morphological and physiological adaptations and life history strategies, as well as the ability to respond plastically to changes in resource availability in ecological time. Determining the ecophysiological responses of plants to changes in root N availability is crucial to further understanding of the mechanisms underlying competitive interactions between plants, and between plants and other organisms, that ultimately contribute to community structure and ecosystem functioning. Carnivorous plants are ideal systems for investigating ecophysiological responses to N availability as:- (i) they share a unique adaptation for obtaining supplemental N from captured prey, therefore ecological stoichiometry and energetic cost/benefit models may be explored; (ii) the trait of botanical carnivory is widely considered to have independently co-evolved as a response to N-deficient, sunny and wet environments, therefore resource allocation trade-offs between plant investment in N and carbon (C) acquisition may be observed, and (iii) they are extremely sensitive to changes in root N availability in ecological time. In this research, the carnivorous plant Drosera rotundifolia (round-leaved sundew) was used to address several unanswered ecophysiological and evolutionary questions relating to patterns and processes of prey capture and the N nutrition of carnivorous plants. Furthermore, the potential for reducing uncertainty in the calculation of plant reliance on carnivory using a δ15N natural abundance multi-level linear mixing model was explored. A combined approach of in-situ and ex-situ studies was employed, using co-occurring non-carnivorous plants or carnivorous plant species with differing evolutionary lineages or prey capture mechanisms respectively to provide context. Results show that the adaptations of carnivory, high reproductive investment and a relatively short life span enable Drosera rotundifolia to survive and thrive in an extreme, N deficient environment. Phenotypically plastic responses by the plant to light and root N availability provide evidence of resource allocation trade-offs between investment in carnivory for N acquisition and in photosynthesis for C acquisition. Plants invested less heavily in prey capture (measured as the stickiness of leaf mucilage) as N availability increased or light availability decreased. These results show that the energetic costs associated with carnivory are avoided by the plant when less costly sources of N are available for uptake and that the production of carbon-rich mucilage is only made under nutrient-limited and well-lit conditions. Results obtained from the comparison of captured insect prey with background invertebrates of potential prey indicate that Drosera rotundifolia is a dietary generalist, where the quantity of prey captured per plant is positively correlated with leaf stickiness and total leaf area. Plant reliance on prey-derived N decreased with increasing root N availability, providing evidence that carnivory is only of net benefit to the plant in N-deficient and well-lit environments, as the photosynthetic costs of investment in the trait are not exceeded by the energetic gain from prey N uptake in shady or dry habitats. A more accurate and precise method for calculating plant reliance on botanical carnivory is presented which incorporates the insect diet of the plant. This method has wider significance for reducing uncertainty in the calculation of relative source contributions to a mixture for most natural abundance applications using a multi-level linear mixing model. To conclude, results from this research further understanding of the ecophysiological mechanisms underlying plant responses to changes in resource availability and the selective pressures driving the evolution of plant adaptations. These results therefore assist with predicting how plants and plant communities may respond to sustained N deposition inputs and future environmental scenarios.
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Educação ecológica para a conservação das plantas carnívoras: um estudo de caso no estado da Paraíba / Ecologic Education for the conservation of carnivorous plants: a case study in the Paraíba StateSilva, Caio Vinícius da 27 February 2014 (has links)
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Previous issue date: 2014-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Carnivorous plants constitute a group of organisms that has well-defined requirements and environmental tolerances, it is recognized as bio-indicators of environmental quality and an important biological control agents of the small animals, possessing the potential educational value driven by the curiosity of the students, facilitating the construction of sensitivity and environmental knowledge. This study sought to use carnivorous plants as didactic instruments for the development of sensitivity, knowledge and environmental action students through environmental education in school. To this end, lectures, workshops, questionnaires, discussions and practical classes with students from regular high school public education were developed. Through studies, it was concluded that the carnivorous plants can be used as a teaching resource facilitator of the assimilation of information related to the local ecosystem, highlighting the importance of popular and scientific knowledge, characterizing and valuing regional habitats and species, encouraging research and dynamizing the teaching and learning process. / Plantas carnívoras constituem um grupo de organismos que detém exigências e tolerâncias ambientais bem definidas, reconhecidas como bioindicadores de qualidade ambiental e importantes agentes no controle biológico de pequenos animais, possuindo potencial valor didático direcionado pela curiosidade do aluno, facilitando a construção da sensibilidade e do saber ambiental. Este trabalho buscou utilizar plantas carnívoras como instrumentos didáticos para o desenvolvimento da sensibilidade, do saber e da ação ambiental dos alunos através da Educação Ambiental na escola. Para tal, foram desenvolvidas palestras, oficinas, questionários, discussões e aulas práticas com alunos do ensino médio regular da educação pública. Através dos estudos, concluiu-se que as plantas carnívoras podem ser utilizadas como recurso didático facilitador da assimilação de informações relacionadas aos ecossistemas locais, evidenciando a importância do conhecimento popular e científico, caracterizando e valorando habitats e espécies regionais, incentivando a pesquisa e dinamizando o processo ensino aprendizagem.
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Láčkovky a jejich využití ve výuce botaniky / Pitcher Plants and Their Use in Teaching BotanyBurian, Michal January 2020 (has links)
The major objective of this thesis are carnivorous plants of the genus Nepenthes and their pedagogical and educational usage addressing students of elementary and grammar schools. The first part provides a general description of the Nepenthes plants, often called tropical pitcher plants due to their pitcher-shaped leaves that function as a passive pitfall trap. Moreover, the field research on the Nepenthes digestive fluid acidity was undertaken at Borneo. Plant's acidity was measured by the pH meter with glass electrode. The results obtained prove pH level differences for various Nepenthes species. In addition, pH level differences in between the fluid from freshly opened pitcher and an older fluid were observed. All results are cross-validated with the values reported in literature. On the basis of the results of the field research, didactic part is assembled. The didactic part consists of the Nepenthes general description and proposal of educational activities aiming at the botany popularization in elementary and grammar schools. Subsequently, the method proposed is tested in biology classes of the second grade of elementary school. The results reveal a positive influence of the method on student's interest in botany.
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Carnivore Movement Ecology for Conservation Prioritization; synthetic, comparative, and machine learning approaches to model large carnivore movement in mixed-use landscapesSchoen, Jay Michael January 2024 (has links)
The impacts of human activities on the natural world have accelerated rapidly in recent centuries and decades. Consequent loss and fragmentation of natural habitats is the greatest threat to short and long-term survival of the planet’s rich biodiversity. Large carnivores are particularly sensitive to these changes, as many species rely on expansive natural areas to maintain healthy, genetically diverse populations.
As a result, this charismatic clade is a focal point of conservation attention, and is also frequently used as a conservation umbrella to conserve other species which share their broad range of habitats. While diminished, fragmented populations and geographic isolation can be detrimental to species longevity, habitat corridors which connect populations throughout a broader human-dominated landscape provide resistance and resilience to the effects of isolation by maintaining genetic connectivity between sub-populations. Accordingly, understanding how large carnivores move through natural and non-natural landscapes to connect with other populations is a key area of research in movement ecology and conservation biology.
In this dissertation, collaborators and I implemented open-source synthetic, comparative, and machine learning approaches to model the movement of tigers and jaguars, two ecologically vital and connectivity-dependent carnivore species, in regions of their ranges which are largely shared with humans.
For Chapters 1 and 2, focusing on tigers in central India, we synthesized five independently derived layers of landscape resistance to derive consensus among existing research (Chapter 1) and comparatively test different movement simulation techniques’ abilities to predict tiger occurrence data (Chapter 2). We found that existing research efforts on habitat quality and potential connectivity areas for tigers in central India were more aligned than independent results indicated. We also derived a geospatial layer for “consensus connectivity areas (CCAs)” – areas where existing research agreed on high potential movement for tigers – and detailed the extensive current and future anthropogenic pressures on these important areas. Additionally, we found that while outputs from several popular techniques for simulating wildlife movement can predict in situ tiger occurrences, a circuit theory-based method, Circuitscape, performed best overall in this landscape and was the most robust to both inputs and validation data used for the analysis.
In Chapter 3, we analyzed a collection of jaguar telemetry data to understand how the environmental responses of jaguar movements vary depending on the behavioral state of the animal. We found that jaguars in a higher (i.e., exploratory) movement state were more likely to move through anthropogenic areas, low tree cover, and areas farther from high tree cover. As similar, less risk-averse behavior has been reported in other carnivores during larger scale movements such as dispersal, these exploratory movement patterns may be a proxy for dispersal movement tendencies and thus more applicable for connectivity planning for jaguars, particularly in mixed-use landscapes. Collectively, this research provides insight into the movement ecology of two threatened large carnivore species as well as multiple open-source methodologies for modeling movement that can be applied to other research questions and conservation objectives worldwide.
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