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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

Estrat?gia reprodutiva do peixe hermafrodita mussum, Synbranchus marmoratus Osteichthyes, Synbranchidae em um a?ude do Rio Grande do Norte, Brasil

Barros, Nirlei Hirachy Costa 27 March 2012 (has links)
Made available in DSpace on 2014-12-17T14:10:29Z (GMT). No. of bitstreams: 1 NirleiHCB_DISSERT.pdf: 6542994 bytes, checksum: b970fd5055cebafb782b426aa47838fa (MD5) Previous issue date: 2012-03-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Reproductive strategy of the hermaphrodite fish the marbled swamp eel, Synbranchus marmoratus (Bloch, 1795) (Osteichthyes: Synbranchidae) was investigated in the Marechal Dutra reservoir, Acari, Rio Grande do Norte, using fish samples captured monthly during the period of July 2010 to July 2011. The limnological parameters and rainfall were verified. The captured fish specimens were numbered, weighed, measured, dissected and their gonads and liver were removed, weighed and identified as to sex and developmental stages of gonads. The length-weight relationship was determined for grouped sex. The size of first gonadal maturation, gonadosomatic index (GSI), condition factor (K) and hepatosomatic index (HSI) were calculated. The development stages of the gonads were investigated using macroscopic and histological techniques, besides the fecundity and reproductive period. The macroscopic characteristics and the histological development of gonads confirmed the four different sexual types in the sampled population: primary males, females, intersex and secondary males. The secondary males were bigger and heavier than all the other types. This species showed a negative allometric growth with a higher increase in length than weight. The size at which 50% of the females began the process of gonadal maturation was 43.5 cm of total length, and for secondary males it was 58.5 cm. Condition factor showed two peaks in February and in April 2011. IGS indicated a reproductive period from July to September 2010 and was negatively correlated with the condition factor and rainfall. IGS showed a negative correlation when compared with the condition factor and the rainy season. HSI was highest in February ad lowest in December. The reproductive period of this species occurs between the end of the rainy season and the beginning of the dry season. S. marmoratus presents a seasonal reproductive strategy which optimizes its reproductive success under the semiarid climatic conditions / A estrat?gia reprodutiva do peixe hermafrodita mussum, Synbranchus marmoratus (Bloch, 1795) (Osteichthyes: Synbranchidae) foi investigada no a?ude Marechal Dutra, Acari, Rio Grande do Norte, utilizando os exemplares capturados mensalmente no per?odo de julho de 2010 a julho de 2011. Foram verificados os par?metros limnol?gicos e a pluviosidade. Os exemplares capturados foram numerados, pesados, medidos, dissecados e o f?gado e as g?nadas foram retiradas, pesadas e identificadas quanto ao sexo e o est?dio de desenvolvimento gonadal. A rela??o peso-comprimento foi determinada para sexos agrupados. O tamanho da primeira matura??o, o ?ndice gonadossom?tico (IGS), o fator de condi??o (K) e o ?ndice hepatossom?tico (IHS) foram determinados. As fases do desenvolvimento das g?nadas foram investigadas usando t?cnicas macrosc?picas e histol?gicas, al?m de determinar a fecundidade e o per?odo reprodutivo da esp?cie. As caracter?sticas macrosc?picas e histol?gicas de desenvolvimento gonadal confirmaram os quatro tipos sexuais diferentes na popula??o dos peixes capturados, sendo: machos prim?rios, f?meas, intersexos e machos secund?rios. Os machos secund?rios apresentaram os maiores valores de comprimento total e peso total. A esp?cie mostrou um crescimento do tipo alom?trico negativo com maior incremento em comprimento do que em peso. O tamanho em que 50% da popula??o das f?meas iniciaram o processo de matura??o gonadal foi de 43,5 cm de comprimento total e para os machos secund?rios foi de 58,5 cm. O fator de condi??o apresentou dois picos, um no m?s de fevereiro e outro m?s de abril de 2011. IGS indicou um per?odo de reprodu??o durante julho a setembro de 2010, mostrando correla??o negativa ao fator de condi??o. IHS mostrou um pico no m?s de fevereiro com o menor valor no m?s de dezembro coincidindo com o per?odo de seca da regi?o. A esp?cie apresenta um per?odo reprodutivo entre o final das chuvas e o in?cio da seca. S. marmoratus mostra uma estrat?gia reprodutiva sazonal que aperfei?oa seu sucesso reprodutivo dentro das condi??es clim?ticas do semi?rido. Palavras chave: mussum, Synbranchus marmoratus, estrat?gia reprodutiva, hermafroditismo, a?ude do semi?rido
62

Wetland Conversion to large-scale agricultural production; implications on the livelihoods of rural communities, Yala Swamp, Lake Victoria basin, Kenya.

Kinaro, Zachary January 2008 (has links)
Wetlands in most parts of the world are under threat of over-exploitation, loss and/or degradation partly due to agriculture and urban land uses. Yala swamp, the largest fresh water wetland in Kenya measuring about 17,500 ha supports a large biodiversity and is source of livelihoods to communities around it. This study addresses the situation where part of this wetland is converted into large-scale agriculture by a multinational company, Dominion Farms (K) Ltd resulting into a conflict and controversy amongst key stakeholders. The study sought to investigate livelihood impacts this transformation has for the local community. It employs the concepts Stakeholder Analysis (SA) and Sustainable Livelihood Approaches (SLA) to asses the livelihood situation in terms of socio-economic conditions, rural infrastructure, income diversification, food security and environmental issues. Data and information have been obtained from primary and secondary sources through field survey at the Yala wetland, in which randomly sampled small-scale farmers, fisher folk, Dominion employees, local leaders and informants, traders and other stakeholders were interviewed using questionnaire and other participatory methods. The main questions were designed to gain information about historical use of the wetland, changes in livelihoods and wetland before and after entry of Dominion Company into the area. From the study, it is evident that assessment of the key stakeholders in relation to this natural resource is of utmost importance for mapping out an acceptable management strategy for the wetland. Besides being cause to a conflict and controversy over control of and access to the swamp, the conversion has resulted into both negative and positive short-term and long-term livelihood impacts to the local community. The wetland being a contested resource with multiple users who claim a stake on it requires a holistic approach in its management that caters for divergent needs and views of key stakeholder groups. The study identifies management issues and proposes abroad vision for the future including recommendations for planning as well as suggestions for specific research needs that should form the basis of action
63

Composição, estrutura e sazonalidade dos bandos mistos de aves em um remanescente de floresta paludosa no sul do Brasil

Silveira, André Barcellos January 2006 (has links)
Analisou-se a composição, estrutura e padrão sazonal de formação dos bandos mistos de aves em um remanescente de floresta paludosa na planície costeira do Rio Grande do Sul, sul do Brasil. Efetuaram-se amostragens mensais de fevereiro de 2005 a janeiro de 2006, com observações ocasionais em 2004 e janeiro de 2005. Pontos de contagem foram utilizados para estimar a abundância relativa das espécies integrantes dos bandos, e transecções foram efetuadas para as observações dos bandos mistos. Quarenta e sete espécies foram registradas como participantes em 92 bandos amostrados. O número de indivíduos foi positivamente correlacionado com o número de espécies dentro dos bandos. O pool dos não-passeriformes foi pobremente representado nos bandos, enquanto passeriformes suboscines e oscines foram igualmente representados na riqueza dos bandos. Onívoros e insetívoros foram bem representados, mas os nectarívoros tiveram apenas uma espécie integrante; frugívoros e granívoros foram ausentes nos bandos mistos.Espécies migratórias foram pouco representadas nos bandos, como havia sido verificado para outras áreas de Floresta Atlântica. A regularidade de uma espécie em integrar bandos mistos foi uma função de sua abundância relativa, e as espécies mais conspícuas tenderam a ser os integrantes mais regulares. Detectaram-se quinze co-ocorrências significativas em 153 combinações possíveis (10%), onze delas positivas e quatro negativas. Nenhum tipo estrutural de bandos foi distinguido por meio de análise de agrupamento. Associações positivas e negativas talvez estejam relacionadas a similaridades e dissimilaridades na distribuição vertical de cada par de espécies. Os atributos de freqüência, tamanho e riqueza dos bandos foram os menores encontrados em qualquer outro estudo na Floresta Atlântica. Os bandos formaram-se o ano inteiro no Faxinal, mas a freqüência, o tamanho e a riqueza dos bandos diferiram significativamente entre os meses e entre as estações. Osvalores máximos destes três atributos foram encontrados na estação não-reprodutiva, lembrando os padrões encontrados em outros locais da Floresta Atlântica. A combinação de um pequeno grupo de espécies abundantes e bem distribuídas, junto com uma baixa riqueza local talvez torne a estrutura dos bandos mistos no Faxinal menos variável do que em outros locais da Floresta Atlântica. / The composition, structure and seasonal pattern of formation of mixed-species bird flocks were analyzed in a swamp forest remnant in the coastal plain of Rio Grande do Sul state, southern Brazil. Field work was carried out monthly from February 2005 to January 2006, plus occasional observations in 2004 and January 2005. Point counts estimated the relative abundance of flocking species, and transects were performed to access data relative to the flocks. Forty seven species were recorded as participants in 92 flocks sampled. The number of individuals was positively correlated with the number of species within the flocks. Non-passerines pool is less represented in the flocks, while suboscines and oscines were equally represented in the flock richness. Omnivores and insectivores were well represented, but nectarivores had only one flocking species while frugivores and granivores were absent in flocks. Migrants had low representation on the composition and structure of flocks, as predicted for lowland Atlantic Forest areas. The regularity of a given species in to integrate flocks was a function of its relative abundance, and the species more conspicuous tended to be the more regular flock joiners. Fifteen significant co-occurrences of 153 possible pairs (10%) were detected, eleven positively and four negatively associated. None structural type of flocks was recognized through cluster analyses. Positive and negative associations were better explained by similarities or dissimilarities on vertical distribution of each species pair. The attributes of frequency, flock size and flock richness were the lowest found in any study on Atlantic Forest. Flocks were formed throughout the year at Faxinal, but frequency, flock size and flock richness differed significantly between months and between seasons. Higher values of these three attributes were found in non-breeding season, reaching the pattern found elsewhere in Atlantic Forest. The combination of a little set of abundant and well distributed speciesand low richness perhaps makes the flock structure at Faxinal less variable than that of Atlantic Forest elsewhere.
64

Etudes écologique, floristique, phytosociologique et ethnobotanique de la forêt marécageuse de Lokoli (Zogbodomey – Bénin): Ecological, floristic, phytosociological and ethnobotanical studies of the swamp forest of Lokoli (Zogbodomey - Benin)

Dan, Bai 29 June 2009 (has links)
La forêt marécageuse de Lokoli, située dans le sud du Bénin est une formation non protégée, bien qu’elle soit la seule forêt marécageuse avec un cours d’eau permanent connue en Afrique de l’Ouest. Pour envisager une prise de décision de conservation et de protection de cet écosystème forestier, il est important de disposer d’une meilleure connaissance de sa flore, de sa végétation et de son fonctionnement. C’est dans ce cadre que la présente étude a été envisagée. Les données collectées concernent le milieu naturel, la structure de la forêt, la régénération naturelle des espèces et les usages faits des Produits Forestiers Non Ligneux (PFNL). Le milieu naturel se compose d’un substratum acide (pH variant de 3,5 à 5,5) et argilo-sableux. Le cortège floristique de cette forêt est composé de 241 espèces réparties en 185 genres et 70 familles dont des espèces endémiques (Uapaca paludosa) ou en danger (Hallea ledermannii), Nauclea xanthoxylon, etc. Sept groupements végétaux ont été identifiés (forêt primaire inondée à Alstonia congensis et Xylopia rubescens, forêt secondaire inondée à Ficus trichopoda et Spondianthus preussii et raphiale à Raphia hookeri et Anthocleista vogelii en forêt ;forêt ripicole à Alchornea cordifolia et Mitragyna inermis, savane marécageuse à Ficus asperifolia et Paullinia pinnata ;prairie marécageuse à Cyclosorus gongylodes et Polygonum pulchrum et enfin prairie marécageuse à Rhynchospora corymbosa et Ludwigia abyssinica en lisière) avec des précisions sur leurs caractéristiques floristiques, biologiques, phytogéographiques et écosociologiques. Les mésophanérophytes sont abondants en forêt alors qu’en lisière, ce sont les microphanérophytes qui sont les plus nombreux. Ces groupements constituent un refuge pour de nombreuses espèces animales dont Barboides britzi, poisson déterminé pour la première fois en 2006. D’après cette étude, on note une bonne régénération des espèces forestières malgré une recrudescence des trouées liées à l’installation de champs de Colocasia esculenta. Parmi les 75 espèces, source de PFNL recensées, les produits et sous-produits issus de Raphia hookeri sont les plus exploités car ils constituent pour les populations riveraines d’importantes sources de revenus. Ces PFNL sont exploités à Lokoli pour plusieurs usages à savoir l’alimentation, l’emballage, boisson alcoolisée, recettes médicinales, construction, etc. Le nombre de pieds de Raphia hookeri saignés par an est de 15.452 par 320 exploitants dont 148 cueilleurs, 81 transformateurs et 91 commerçants ;ce qui fournit aux exploitants des revenus de l’ordre de 28.000 à 159.000 FCFA (42,7 à 242,4 euros) par mois et par exploitant, sans oublier les autres activités menées par les riverains dans cet écosystème. On note une forte pression anthropique sur cette formation qu’il est donc urgent de protéger. En effet, elle dispose d’importants atouts qui militent en faveur de sa conservation. Elle abrite des espèces végétales et animales rares, endémiques, vulnérables et en danger (inscrites sur la liste rouge de l’UICN), telles que :Hallea ledermannii, Uapaca paludosa, Nauclea xanthoxylon, Cercopithecus erythrogaster erythrogaster, Cercopithecus mona, Colobus vellerosus, Ceriagrion citrinum Campion, Barboides britzi, etc. La forêt marécageuse de Lokoli joue un rôle de refuge pour toutes ces espèces qui y trouvent leur niche écologique. Sur le plan socio-économique, la FML fournit aux populations riveraines des revenus pour leur subsistance. Toutes ces potentialités font d’elle une Forêt à Haute Valeur pour la Conservation (FHVC) et elle pourrait constituer une véritable réserve de biosphère dans le Sud-Bénin. / The swamp forest of Lokoli, located in the south of Benin, is a non-protected area, although it is the only swamp forest in West Africa accompanied by a river which always contains water. To be able to make decisions concerning the conservation and protection of this forest ecosystem, it is important to have a better knowledge of its flora, its vegetation and its ecology and dynamics. It is within this framework that the present study was considered. The data that were collected relate to the natural environment, the structure of the forest, the natural regeneration of the species and the uses of the Non Timber Forest Products (NTFP). The natural environment is composed of a substratum which is acid (pH varying from 3.5 to 5.5) and loamy-sandy. The floristic composition of this forest is composed of 241 plant species from 185 genera and 70 families. Seven vegetation types were identified: 1. Inundated primary forest with Alstonia congensis and Xylopia rubescens; 2. Inundated secondary forest with Ficus trichopoda and Spondianthus preussii; 3. Raphia forest with Raphia hookeri and Anthocleista vogelii; 4. Riparian forest with Alchornea cordifolia and Mitragyna inermis; 5. Marshy savanna with Ficus asperifolia and Paullinia pinnata; 6. Marshy savanna with Cyclosorus gongylodes and Polygonum pulchrum; and 7. Marshy savanna with Rhynchospora corymbosa and Ludwigia abyssinica. Precise details are given on their floristic, biological, phytogeographical and phytosociological characteristics. The mesophanerophytes are abundant in forest whereas at forest edges the microphanerophytes are most numerous. These vegetation types constitute a refuge for many animal species, for example Barboides britzi, a species of fish first identified in 2006. This study noted a good regeneration of forest species, in spite of disturbance related to the installation of fields of Colocasia esculenta. About 75 investigated NTFP are exploited in Lokoli for many purposes, among which food, packaging, alcoholic drinks, medicines, construction, etc. Among the listed NTFP, the products and by-products made from Raphia hookeri are the most important because they are important sources of revenue for the inhabitants of the area. The number of stems of Raphia used per year for palm wine production is 15.452 by the 320 inhabitants, including 148 gatherers, 81 transformers and 91 tradesmen. This provides to the inhabitants an income of about 28,000 to 159,000 FCFA per month and per inhabitant, without forgetting the other activities undertaken by these inhabitants. This results in a strong human pressure on the vegetation of the area which is therefore in urgent need of protection. The vegetation of the Lokoli forest has important values which indicate its conservation concern. It shelters plant and animal species that are endemic and/or endangered or vulnerable according to the red list of the IUCN, such as: Hallea ledermannii, Uapaca paludosa, Nauclea xanthoxylon, Cercopithecus erythrogaster erythrogaster, Cercopithecus mona, Colobus vellerosus, Ceriagrion citrinum Campion, Barboides britzi, etc. The swamp forest of Lokoli is a refuge for all these species who find here their ecological niche. On the socio-economic level, the Lokoli forest provides to the inhabitants an income for their subsistence. The Lokoli forest in southern Benin is a forest with a high conservation value and it has the potential to become a “biosphere reserve”. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
65

Small Mammal Survey of John U. Lloyd Beach State Park, Dania Beach, Florida.

Goldman, Ryan A. 01 May 2013 (has links)
Urban development and human encroachment on the natural habitats along the coastline of Florida combined with invasive exotic pressures have resulted in the fragmentation and degradation of habitat quality within Broward County. Native habitats have been significantly altered and fragmented to a fraction their previous size. With loss of habitat area and quality, isolation of breeding populations and anthropogenic pressures, it is important to determine species composition and habitat utilization in order to conserve the remaining biological diversity. It was the intent of this study to determine the small mammal species’ population structure and habitat utilization by season in the four sampled habitats. Previously undocumented species and/or extralimital populations were predicted prior to sampling. John U. Lloyd Beach State Park in Dania Beach, Florida is an understudied location for small mammals. This study surveyed four terrestrial habitats for small mammal species using live trapping and mark/recapture techniques. Data were collected monthly over the span of thirteen months to determine habitat use from maritime hammock, mangrove swamp, coastal dune and ruderal habitat types to determine species composition and mass of individual captures and recaptures. Trapping (3749 trap nights) produced twenty-four captures (including recaptures) in two of the four habitat types: maritime hammock and coastal strand. No animals were captured in the mangrove swamp or ruderal habitats, both of which were dominated by invasive Australian pine (Casuarina equisetifolia) monocultures. Post study, a large habitat restoration project restored the habitats impacted by invasive exotic flora. This survey serves as a baseline for small mammals in the park, documenting the pre-restoration habitat use and species composition. Future study to determine changes in species composition post-restoration is recommended.
66

Examining the Effect of Neighbourhood Segregation and Socioeconomic Factors on the Food Environment: A Bayesian Hierarchical Spatial Analysis Using INLA

Yankey, Ortis 12 April 2022 (has links)
No description available.
67

Studentský dům na Starém Brně / Student House in the Neighbourhood Old Brno

Kadaňka, Petr January 2009 (has links)
Old Brno as a centre of students‘ life. Culturally-social potential can be used for a development of education especially by virtue of creating sufficient social background for more intensive students‘ life in the centre of Brno. Regulation of problematic Mendel Square rectifies transportation and gives back recreational character of the area. It is connected with a conception of the student house as a combination of simple and low-cost living and background for students‘ leisure time. Top part of the Křížová Street is become a colonnade whose recreative importance is seconded by vertical swamps of the new student house.
68

Studentský dům na Starém Brně / Student House in the Neighbourhood Old Brno

Kadaňka, Petr January 2009 (has links)
Old Brno as a centre of students‘ life. Culturally-social potential can be used for a development of education especially by virtue of creating sufficient social background for more intensive students‘ life in the centre of Brno. Regulation of problematic Mendel Square rectifies transportation and gives back recreational character of the area. It is connected with a conception of the student house as a combination of simple and low-cost living and background for students‘ leisure time. Top part of the Křížová Street is become a colonnade whose recreative importance is seconded by vertical swamps of the new student house.
69

“lurking about the neighbourhood”: Slave Economy and Petit Marronage in Virginia and North Carolina, 1730 to 1860

Nevius, Marcus Peyton 06 September 2016 (has links)
No description available.
70

A Deep History of Shallow Waters: Enclosing the Wetland Commons in the Era of Improvement

Allen, Davis 23 May 2022 (has links)
No description available.

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