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It is evident that Ethiopia is one of the countries of Africa that is experiencing significant population growth as well as land use/cover dynamics. Land use/cover induced degradation of natural resources is a major challenge to the country’s development. The main objective of this study was to investigate the impact population dynamics has had on land use/cover in Mandura district. Data on population over time were taken from the CSA during the 1984, 1994 and 2007 national census results. A total of 210 farm households from three kebeles: 105 from the local people and 105 from migrants were surveyed in May 2011 to acquire data on socioeconomic, land use, resource use and management. Aerial photographs of 1957, 1982 and SPOT-5 image of the 2006/07 were used to generate data on land use/cover changes. The results indicate that population has substantially increased, more than fourfold between 1957-2006/07, mainly due to migration from the surrounding areas, government sponsored resettlements, and flourishing of new urban centers. No less important is mortality has decreased due to immunization and the birth rate has been increasing due to improved maternal and child care as compared to the situation prior to the 1990s. The change on land use/cover show that from the total land use/cover conversions, which totals 58,403 ha of land, farm land constitutes 90.1 %. The study finds natural population increase, migration, urbanization, agricultural extensification, institutional weakness, land tenure insecurity, famine and drought, and poverty as root causes. The study further identifies existence of all weather road, resettlement, Tana-Beles project, expansion of agriculture, land colonization, wood extraction for fuel, and soil fertility decline as direct causes of land use/cover changes. As a result of change of customary land tenure system, the local population has been forced to engage in extractive economic activities that have never been practiced in the past. Therefore, the study calls for coordinated efforts for resources use and management at different levels, land use policy formulation, devising alternative sources of livelihoods and fuel, regulating migration and involvement of the wider community in policy formulation and implementations. / Geography / D. LITT. et. Phil. (Geography)

La diaspora chinoise a pris de l’ampleur depuis la deuxième moitié du XIXème siècle. En France, la migration de Chinois originaires de la région de Wenzhou, s’est intensifiée depuis les années 1980. Ce sous-groupe de la diaspora chinoise a dès lors rapidement développé ses activités économiques. L’objectif cette thèse consiste à étudier l’organisation économique, sociale et spatiale des migrants de Wenzhou en France, principalement dans la région parisienne, et d’analyser les rapports économiques et sociaux que ceux-ci entretiennent avec la Chine en général et avec leur région d’origine en particulier. L’hypothèse centrale de la thèse est que le « Modèle de Wenzhou » en Chine, tel qu’il est identifié et analysé par les universitaires chinois, et le développement de l’entrepreneuriat chinois issu de Wenzhou en France sont étroitement liés. Pour ce faire, nous interrogerons notamment l’idée d’une « importation » de ce modèle en France. Les résultats de cette thèse permettent de révéler l’existence d’une économie transnationale originale, reliant la France et la Chine, qui a été soutenue par la diaspora Wenzhou et a produit une forme de « transfert migratoire » dans chacun des deux pays. Plus largement, la thèse permet de montrer de quelle manière la diaspora chinoise en France a contribué au développement économique de la Chine et comment elle a pu bénéficier de la nouvelle politique de la Chine initiée au début des années 2000 pour se consolider. / The Chinese diaspora has been growing since the second half of the nineteenth century. In France, the Chinese immigration from the region of the Wenzhou has intensified since the 1980s. This sub-group of the Chinese diaspora has since rapidly expanded its economic activities. The objective of this thesis is to study the economic, social and spatial organization of Wenzhou migrants in France, manly in the Paris region, and to analyze the economic and social relations that they maintain with China in general and with their region of origin in particular. The central hypothesis of the thesis is that the economic “model of Wenzhou” area, as identified and analyzed by the Chinese scholars, and the development of Chinese entrepreneurship in France are closely linked in particular through "Import"of this model in France. The results of our thesis reveal the existence of an original transnational economy connecting France and China, that was supported by the Wenzhou diaspora and that produced a form of "migratory transfer" in each of the two countries. More broadly, the thesis helps to show how the Chinese diaspora in France contributed to the economic development of China, but also how it benefitted from measures included in China's new policy initiated in the early 2000s to consolidate itself.

Os amarelos estão associados a fitoplasmas, procariotos pertencentes à classe Mollicutes que não possuem parede celular e habitam o floema de plantas. Os danos causados pelas doenças de etiologia fitoplasmática são relevantes e podem ocorrer em diversas espécies economicamente importantes. Em videira, pesquisas realizadas em várias partes do mundo têm relatado a presença das doenças do tipo "amarelo", porém, no Brasil, estas doenças ainda não foram relatadas para esta cultura. Em vinhedos comerciais localizados nos Estados de São Paulo e Paraná têm sido observadas plantas com sintomas semelhantes àqueles provocados por fitoplasmas em outros países. Estes sintomas têm sido caracterizados por amarelecimento e ou avermelhamento foliar, necrose do limbo e rachaduras nas nervuras principais. Com o objetivo de detectar e identificar molecularmente fitoplasmas associados a estes tipos de sintomas, folhas e ramos foram amostrados a partir de plantas sintomática e assintomáticas. A detecção foi conduzida com PCR duplo usando-se os iniciadores R16 mF1/mR2 ou P1/P7 na primeira reação e R16 F2n/R2 na segunda reação. A identificação foi realizada através de PCR duplo com iniciadores específicos e análises de RFLP com as enzimas de restrição AluI, RsaI, KpnI, MseI, HhaI, HpaII, HinfI e MboI. Em 23 plantas amostradas, fitoplasmas foram detectados em 10 delas, através da amplificação do 16S rDNA, visualizado em gel de agarose na forma de bandas de 1,2Kb. A identificação por PCR demonstrou que os fitoplasmas associados ao amarelo da videira pertenciam aos grupos 16SrI e 16SrIII. As análises dos perfis eletroforéticos obtidos com o uso da técnica de RFLP revelaram a presença de fitoplasmas afiliados ao subgrupo 16SrI-B. A constatação de fitoplasmas pertencentes a estes dois grupos nas plantas amostradas demonstraram a ocorrência da doença conhecida como amarelo da videira nos Estados de São Paulo e Paraná. As pesquisas desenvolvidas neste trabalho vêm contribuir para aumentar os conhecimentos sobre o papel e a diversidade dos fitoplasmas no agroecossistema brasileiro. / Yellows diseases are associated with phytoplasmas, wall-less prokaryotes, inhabitant of phloem vessels. Damage caused by these diseases are relevant for some important cultivated botanical species. Grapevine yellows diseases have been observed in several areas of the world, but in Brazil the presence of these diseases had not been reported yet. In vineyards located in São Paulo and Paraná States, plants exhibiting symptoms similar those observed in grapevines from other countries have been observed. The symptoms were characterized by yellowing or redding of leaf blade and ribs, leaf blade necrosis and main ribs fissures. In order to detect and identify phytoplasmas associated with those kind of symptoms, leaves and stems were sampled from symptomatic and asymptomatic plants. The phytoplasma detection was conducted with nested PCR using the primer pairs R16mF1/mR2 or P1/P7 for first reaction and 16 F2n/R2 for second reaction. The identification was carried out by nested PCR with group-specifc primer pairs and RFLP analyses with enzymes AluI, RsaI, KpnI, MseI, HhaI, HpaII, HinfI and MboI. From a total of 23 samples analysed, phytoplasmas were detected in 10 of them, through amplification of the 16S rDNA, visualized through a 1.2Kb band in agarose gel. The identification by PCR demonstrated that phytoplasmas associated with grapevine yellow belong to 16SrI and 16SrIII groups. Analyses of electrophoretic profiles revealed the presence of phytoplasmas affiliated to 16SrI-B subgroup. The presence of phytoplasmas belonging to these two groups in the sampled plants demonstrated the occurrence of yellow disease in grapevine in São Paulo and Paraná States. The investigation conducted in the present work contributed to the knowledgement of the role and the diversity of phytoplasmas in Brasilian ecosystem.

It is evident that Ethiopia is one of the countries of Africa that is experiencing significant population growth as well as land use/cover dynamics. Land use/cover induced degradation of natural resources is a major challenge to the country’s development. The main objective of this study was to investigate the impact population dynamics has had on land use/cover in Mandura district. Data on population over time were taken from the CSA during the 1984, 1994 and 2007 national census results. A total of 210 farm households from three kebeles: 105 from the local people and 105 from migrants were surveyed in May 2011 to acquire data on socioeconomic, land use, resource use and management. Aerial photographs of 1957, 1982 and SPOT-5 image of the 2006/07 were used to generate data on land use/cover changes. The results indicate that population has substantially increased, more than fourfold between 1957-2006/07, mainly due to migration from the surrounding areas, government sponsored resettlements, and flourishing of new urban centers. No less important is mortality has decreased due to immunization and the birth rate has been increasing due to improved maternal and child care as compared to the situation prior to the 1990s. The change on land use/cover show that from the total land use/cover conversions, which totals 58,403 ha of land, farm land constitutes 90.1 %. The study finds natural population increase, migration, urbanization, agricultural extensification, institutional weakness, land tenure insecurity, famine and drought, and poverty as root causes. The study further identifies existence of all weather road, resettlement, Tana-Beles project, expansion of agriculture, land colonization, wood extraction for fuel, and soil fertility decline as direct causes of land use/cover changes. As a result of change of customary land tenure system, the local population has been forced to engage in extractive economic activities that have never been practiced in the past. Therefore, the study calls for coordinated efforts for resources use and management at different levels, land use policy formulation, devising alternative sources of livelihoods and fuel, regulating migration and involvement of the wider community in policy formulation and implementations. / Geography / Ph. D. (Geography)

Os amarelos estão associados a fitoplasmas, procariotos pertencentes à classe Mollicutes que não possuem parede celular e habitam o floema de plantas. Os danos causados pelas doenças de etiologia fitoplasmática são relevantes e podem ocorrer em diversas espécies economicamente importantes. Em videira, pesquisas realizadas em várias partes do mundo têm relatado a presença das doenças do tipo “amarelo”, porém, no Brasil, estas doenças ainda não foram relatadas para esta cultura. Em vinhedos comerciais localizados nos Estados de São Paulo e Paraná têm sido observadas plantas com sintomas semelhantes àqueles provocados por fitoplasmas em outros países. Estes sintomas têm sido caracterizados por amarelecimento e ou avermelhamento foliar, necrose do limbo e rachaduras nas nervuras principais. Com o objetivo de detectar e identificar molecularmente fitoplasmas associados a estes tipos de sintomas, folhas e ramos foram amostrados a partir de plantas sintomática e assintomáticas. A detecção foi conduzida com PCR duplo usando-se os iniciadores R16 mF1/mR2 ou P1/P7 na primeira reação e R16 F2n/R2 na segunda reação. A identificação foi realizada através de PCR duplo com iniciadores específicos e análises de RFLP com as enzimas de restrição AluI, RsaI, KpnI, MseI, HhaI, HpaII, HinfI e MboI. Em 23 plantas amostradas, fitoplasmas foram detectados em 10 delas, através da amplificação do 16S rDNA, visualizado em gel de agarose na forma de bandas de 1,2Kb. A identificação por PCR demonstrou que os fitoplasmas associados ao amarelo da videira pertenciam aos grupos 16SrI e 16SrIII. As análises dos perfis eletroforéticos obtidos com o uso da técnica de RFLP revelaram a presença de fitoplasmas afiliados ao subgrupo 16SrI-B. A constatação de fitoplasmas pertencentes a estes dois grupos nas plantas amostradas demonstraram a ocorrência da doença conhecida como amarelo da videira nos Estados de São Paulo e Paraná. As pesquisas desenvolvidas neste trabalho vêm contribuir para aumentar os conhecimentos sobre o papel e a diversidade dos fitoplasmas no agroecossistema brasileiro. / Yellows diseases are associated with phytoplasmas, wall-less prokaryotes, inhabitant of phloem vessels. Damage caused by these diseases are relevant for some important cultivated botanical species. Grapevine yellows diseases have been observed in several areas of the world, but in Brazil the presence of these diseases had not been reported yet. In vineyards located in São Paulo and Paraná States, plants exhibiting symptoms similar those observed in grapevines from other countries have been observed. The symptoms were characterized by yellowing or redding of leaf blade and ribs, leaf blade necrosis and main ribs fissures. In order to detect and identify phytoplasmas associated with those kind of symptoms, leaves and stems were sampled from symptomatic and asymptomatic plants. The phytoplasma detection was conducted with nested PCR using the primer pairs R16mF1/mR2 or P1/P7 for first reaction and 16 F2n/R2 for second reaction. The identification was carried out by nested PCR with group-specifc primer pairs and RFLP analyses with enzymes AluI, RsaI, KpnI, MseI, HhaI, HpaII, HinfI and MboI. From a total of 23 samples analysed, phytoplasmas were detected in 10 of them, through amplification of the 16S rDNA, visualized through a 1.2Kb band in agarose gel. The identification by PCR demonstrated that phytoplasmas associated with grapevine yellow belong to 16SrI and 16SrIII groups. Analyses of electrophoretic profiles revealed the presence of phytoplasmas affiliated to 16SrI-B subgroup. The presence of phytoplasmas belonging to these two groups in the sampled plants demonstrated the occurrence of yellow disease in grapevine in São Paulo and Paraná States. The investigation conducted in the present work contributed to the knowledgement of the role and the diversity of phytoplasmas in Brasilian ecosystem.