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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.
281

Mobilidade residencial intrametropolitana na RM de Campinas : uma abordagem a partir da distribuição espacial dos migrantes / Intrametropolitan residential mobility of Metropolitan Region of Campinas : an approach fron the spatial distribution of migrants

Dota, Ednelson Mariano, 1986- 13 April 2015 (has links)
Orientador: José Marcos Pinto da Cunha / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-27T16:03:29Z (GMT). No. of bitstreams: 1 Dota_EdnelsonMariano_D.pdf: 6083518 bytes, checksum: 138d84d9213201ff5b78be338424be28 (MD5) Previous issue date: 2015 / Resumo: Dentre as necessidades básicas dos indivíduos, o morar tem papel de grande relevância, já que representa segurança e privacidade, do ponto de vista individual, e acessibilidade, considerando a localização da habitação frente ao conjunto de processos e fenômenos distribuídos diferencialmente no território. É na interação entre o movimento dos grupos populacionais, através da migração e da mobilidade residencial, e os resultados territoriais da distribuição espacial desses grupos nos municípios componentes da Região Metropolitana de Campinas que se assenta o foco desta pesquisa. Tendo esta região permanecido como importante pólo demográfico para os fluxos migratório interestaduais e intraestaduais, continuou a receber relevante volume de migrantes das mais variadas características, apesar das mudanças econômicas e sociais das últimas décadas ter alterado o volume e direcionamento dos fluxos migratórios em nível nacional. Como resultado, se verifica o recebimento de migrantes de longas e curtas distâncias, além dos movimentos internos que tem se sobressaído para a produção e estruturação do espaço urbano regional, a partir da expansão de áreas periféricas com distintas características construtivas e de infraestrutura. A mobilidade, neste início de século XXI, tem culminado num aprofundamento das desigualdades territoriais, já que, em grande parte, a expansão territorial ocorre seguindo as características dos grupos sociais predominantes nas áreas em que são construídos os produtos habitacionais, pela valorização da localização, além do aumento da relevância da mobilidade residencial intrametropolitana para os processos de produção e estruturação do espaço urbano regional. Os incentivos e constrangimentos, que são os fatores motivadores e colocam a população em movimento estão, cada vez mais, mobilizando grupos sociais mais bem posicionados em relação a escolaridade e renda, fato novo em relação ao que se observava em momentos anteriores e que tem grande destaque na forma e característica da expansão urbana observada nos municípios RM de Campinas. A análise das diferenças e similaridades entre migrantes e não-migrantes, além de migrantes em suas distintas modalidades, é uma das escolhas metodológicas utilizadas para compreender e avançar na análise e compreensão da dinâmica migratória na RM de Campinas / Abstract: Among the basic individuals' needs, the reside has a very relevant role, whereas it represents security and privacy, from an individual point of view, and accessibility, considering the habitation location in front of a set of processes and differentially distributed phenomena in the territory. It is in the interaction between the movement of population groups, through migration and residential mobility, and the territorial results of the spatial distribution of these groups in the city included in the Metropolitan Region of Campinas whose research focus is based on. Having this region remained as a significant demographic pole for interstate and intrastate migration flows, it continued receiving relevant volume of migrants from a variety of characteristics, despite the economic and social changes of the recent decades have modified the volume and direction of migration flows at national level. As a result, it is verified the migrants' receipt of long and short distances, besides the internal movements that have been outstanding for the production and structuration of the regional urban space, from the expansion of peripheral areas with distinct construction and infrastructure characteristics. The mobility, in the beginning of XXI century, has culminated in a deepening of regional disparities, seeing that, for the most part, territorial expansion occurs following the characteristics of the prevailing social groups in areas where housing products are built, through the location valuation, beyond the relevance increasing of intra-metropolitan residential mobility for the production and structuration processes of the regional urban space. The incentives and constraints, which are the motivating factors and put the population in movement are, increasingly, mobilizing better positioned social groups in relation to education and income levels, a new fact in relation to what was observed in previous moments and that has great importance in urban growth form and feature observed in MR (Metropolitan Region) cities of Campinas. The analysis of differences and similarities between migrants and non- migrants , and migrants in its various forms , is one of the methodological choices used to understand and advance the analysis and understanding of migration dynamics in the Metropolitan Region of Campinas / Doutorado / Demografia / Doutor em Demografia
282

Fatores de risco, distribuição espacial e perspectivas de controle da malária: estudo longitudinal em uma comunidade rural da Amazônia (Granada, Acre). / Risk factors, spatial distribution and perspectives for malaria control: a longitudinal study in a rural community in the Amazon (Granada, Acre).

Mônica da Silva Nunes 15 October 2008 (has links)
Apresenta-se os resultados de estudo de coorte em um assentamento rural no Acre, Brasil, onde 509 indivíduos contribuíram com 489,7 pessoas-ano de seguimento. A incidência de malária por Plasmodium vivax e Plasmodium falciparum foi de 30,0/100 e 16,3/100 pessoas-ano, respectivamente. A morbidade por malária se associou fortemente ao desmatamento e agropecuária e diminuiu após 5 anos de residência no local; além disso ocorreram conglomerados espaciais significantes de casos de malária vivax e falciparum em áreas de ocupação recente. Não houve associação entre alótipos do receptor FcgRIIa, promotor Duffy ou anticorpos contra a PvMSP-1, e malária no seguimento. As respostas humorais e celulares foram mais freqüentes contra as porções C- e N-terminal da PvMSP-1 respectivamente, porém sem relação com as variantes de PvMSP-1 infectantes. O espectro clínico dos episódios de malária foi variado; enquanto cefaléia, febre e mialgia foram sintomas freqüentes, 29,4% dos episódios eram assintomáticos. Os resultados mostram que a aquisição de imunidade clínica é adquirida em áreas de baixa transmissão e que mudanças ambientais causadas nos assentamentos rurais perpetuam a transmissão de malária. Estes achados são de extrema importância para o controle da malária na Amazônia. / Here a cohort study in a frontier settlement in Acre, Brazil, where 509 subjects contributed 489.7 person-years of follow-up, is described. Incidence rates for Plasmodium vivax and Plasmodium falciparum malaria were 30.0/100 and 16.3/100 person-years at risk, respectively. Malaria morbidity was strongly associated with land clearing and farming, and decreased after 5 years of local residence. Besides, there was significant spatial clustering of vivax and falciparum malaria in areas of recent occupation. No significant association was found between FcgRIIa allotype, Duffy promoter type or presence of antibodies against PvMSP-1 and malaria in the follow-up. Humoral and cellular responses were more common against the C- and N-terminal portions of PvMSP-1 respectively, but did not match the PvMSP-1 variants found in infecting parasites. The clinical spectrum of malaria episodes varied widely; while headache, fever and myalgia were the most frequent symptoms, 29.4% of the episodes were asymptomatic. The results show that clinical immunity is acquired under low malaria transmission and environmental changes occurring in the settlements perpetuate malaria transmission. These findings are of utmost importance for malaria control in the Amazon.
283

Diversity, spatial and temporal distribution of anurans (Amphibia) in the Mantiqueira mountais range, southeastern Brazil / Diversidade, distribuição espacial e temporal de anuros (Amphibia) na Serra da Mantiqueira, sudeste do Brasil

Andre Ceruks 05 March 2010 (has links)
O presente trabalho pretende contribuir para um maior conhecimento dos anfíbios anuros que ocorrem na Serra da Mantiqueira, no município de Monteiro Lobato,SP. O estudo objetivou inventariar as espécies, caracterizar a riqueza, abundância e diversidade, bem como o uso dos hábitats, e micro-hábitats das espécies de anuros registradas, além de fornecer informações para o gerenciamento e sua conservação, podendo futuramente, ser referência para trabalhos similares. A área de estudo se encontra em região de Mata Atlântica com domínio da Floresta Ombrófila Densa, no município de Monteiro Lobato, bairro da Pedra Branca (220 56S e 450 44W). As atividades de campo foram realizadas quinzenalmente, principalmente no período noturno, totalizando 50 amostragens, entre julho de 2007 e julho de 2009. Foram registradas 34 espécies em 17 gêneros de anfíbios anuros, pertencentes a onze famílias: Bufonidae (n=2), Brachycephalidae (n=4), Centrolenidae (n=1), Craugastoridae (n=1), Cycloramphidae (n=1), Hylidae (n=16), Hylodidae (1 espécie), Leuperidae (n=2), Leptodactylidae (n=4), Microhylidae (n=1), Ranidae (n=1). A riqueza de espécies registrada para área de estudo foi considerada alta e quatro dos sete ambientes amostrados apresentaram alta diversidade de espécies (H). A hipótese que melhor explica esses resultados é que a área de estudo apresenta um gradiente de formações vegetacionais distintas, desde a área aberta, passando pela borda florestal até o interior de mata, possibilitando assim a ocorrência de espécies que usam tanto a floresta como a área aberta, ou para reprodução ou para refúgio. O maior número de espécies, que variou de 17 a 27, ocorreu entre os meses mais quentes e chuvosos do ano, padrão esperado para regiões tropicais sazonais, com influencia da temperatura. A sobreposição quanto ao uso de substrato como sítio de vocalização foi maior entre as espécies cujos machos vocalizaram empoleiradas na vegetação, do que entre os machos das espécies que vocalizaram sobre o solo. Esse resultado deve decorrer do maior número de espécies da família Hylidae registrado no presente estudo (47% dos anuros). Além disso, houve maior sobreposição entre as espécies de área aberta e de borda florestal do que no interior de floresta, resultado esse explicado pela maior riqueza de espécies e menor estratificação vegetal que diminuem a partilha de espaço. A similaridade na composição de espécies do presente estudo foi comparada com 15 localidades do Estado de São Paulo e foram associadas à fisionomia vegetal dominante, distância e altitude das áreas amostradas. Os subgrupos formados na análise de similaridade sugerem que a topografia e o gradiente altitudinal são um fator II primário que aponta as semelhanças na composição de espécies de anuros em conjunto com a distância entre as localidades. / This study aims to contribute to a better knowledge of amphibians that occur in the Mantiqueira mountain range in the city of Monteiro Lobato,SP, Brazil. The study aimed to inventory the species, to characterize the richness, abundance and diversity, as well as the use of habitats and microhabitats of frog species recorded, in addition to providing information for management and conservation, and may eventually be the reference for a similar studies. The area of study is in the Atlantic forest region with dense rain forest in the city of Monteiro Lobato, district of Pedra Branca (220 56S e 450 44W). The field activities were carried out fortnightly, mainly at night, totaling 50 samples, between July 2007 and July 2009. We recorded 34 species in 17 genera of frogs belonging to eleven families: Bufonidae (n = 2), Brachycephalidae (n = 4), Centrolenidae (n = 1), Craugastoridae (n = 1), Cycloramphidae (n = 1), Hylidae (n = 16), Hylodidae (n=1), Leuperidae (n = 2), Leptodactylidae (n = 4), Microhylidae (n = 1), Ranidae (n = 1). The species richness recorded for the study area was considered high and four of the seven study sites had high species diversity (H). The hypothesis that best explains these results is that the study area has a gradient of vegetation formations different from the open area, through the forest edge to the forest interior, allowing the occurrence of species that use both the forest and the area open, or for breeding or refuge. The greatest number of species, ranging from 17 to 27, was among the warmest and rainy months of the year, expected pattern for tropical seasonal regions influenced for the temperature. The overlap in the use of substrate as calling site was greatest among species that vocalized perched on vegetation, than among males of species that on the ground. This result should come from the greater number of species of the family Hylidae recorded in this study (47% of species). Furthermore, there was significant overlap between the species of open area and forest edge than in interior forest, the result explained by the higher species richness and lower bedding plant that reduce the sharing of space. The similarity in species composition of the present study were compared with 15 locations in the State of Sao Paulo and were associated with the dominant vegetation type, distance and altitude of the sampled areas. The subgroups formed on the similarity analysis suggests that topography and altitudinal gradient is a primary factor that points to the similarities in composition of frogs in conjunction with the distance between locations.
284

Epidemiologia da malária: incidência, distribuição espacial e fatores de risco em uma coorte rural amazônica. / Epidemiology of malaria: incidence, spatial distribution and risk factors in a rural Amazon cohort.

Natal Santos da Silva 18 April 2011 (has links)
Um estudo foi desenvolvido numa coorte localizada em um assentamento agrícola no Acre, Brasil, com o objetivo de identificar fatores de risco de malária. Ao longo de 70 meses, acompanharam-se 531 indivíduos, que contribuíram com 2.281,53 pessoas-ano. Registraram-se 443 casos de malária por Plasmodium vivax, 129 por P. falciparum e 27 de malária mista (P. vivax e P. falciparum). A análise espacial de varredura identificou clusters de malária no final da área de estudo, próximo ao limite da floresta. Nessa análise, 69,1% de todos os casos de malária ocorreram em apenas 27 domicílios (22,3% do total), os quais estavam dentro de um raio de 2,2 Km ao centro do cluster. Quatro estudos transversais foram realizados ao longo do seguimento e infecções assintomáticas foram detectadas pela PCR aninhada. Modelos de fragilidade identificaram o local de moradia como a principal covariável relacionada ao risco de aquisição de malária tanto nos modelos não ajustado quanto nos ajustado. Este tipo de análise pode otimizar as ações de combate à malária e reduzir custos operacionais. / A study was developed in a cohort located in an agricultural settlement in Acre, Brazil, aiming to identify risk factors of malaria. Over 70 months followed up 531 individuals who contributed 2281.53 people-years. It was recorded 443 cases of malaria by Plasmodium vivax, 129 by P. falciparum and 27 mixed malaria (P. vivax and P. falciparum). The spatial analysis canning identified clusters of malaria at the end of the study area, near the forest border. In this analysis, 69.1% of all malaria cases occurred in only 27 households (22.3% of total), which were within a radius of 2.2 km from the clusters center. Four cross-sectional studies were conducted along the follow-up and asymptomatic infections were detected by nested PCR. Frailty models identified the housing location as the main covariate related risk of acquiring malaria in both unadjusted and adjusted models. This type of analysis may optimize actions against malaria, and reduce operational costs.
285

Uso de ?gua da chuva e a incid?ncia de diarreia em crian?as

Ara?jo Junior, Pascoal do Sacramento 01 April 2016 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-08-24T00:22:08Z No. of bitstreams: 1 DISSERTA??O UEFS-1.pdf: 4397842 bytes, checksum: 5bbf7864e46035d01b3cd15d9b25b50d (MD5) / Made available in DSpace on 2016-08-24T00:22:08Z (GMT). No. of bitstreams: 1 DISSERTA??O UEFS-1.pdf: 4397842 bytes, checksum: 5bbf7864e46035d01b3cd15d9b25b50d (MD5) Previous issue date: 2016-04-01 / It is important to emphasize that both the quality of the water as the quantity and regularity of supply are determining factors for the emergence of diseases in humans. Therefore, we used the epidemiological ecological study, quantitative, in order to assess the consumption of rainwater and the incidence of diarrhea in children under 5 years of age: the exposed, which use capture systems roof rain water which is stored in tanks for potable purposes, composed of 111 children of the city of Lowland Ro?a-Ba; and not exposed, which use public water supply, composed also by 111 children of the city of Baixa Grande-Ba. Health indicators were adopted that diarrhea and measured over a period of 90 days. They were applied form, spreadsheet and field observation form with the families and children participating in the survey. The analysis of data obtained from said diarrhea and measured showed a significant association between episodes of diarrhea in the total sample of children studied and the spatial distribution where the highest concentrations occurred. Children who drank rain water had higher risk in percentage and time of occurrence, to have episodes of diarrhea than children who drink tap water, but with a difference not very acentuda. The incidence in children who consume rainwater stored in cisterns was 11.1%, and 5.8% in families who drink tap water. / ? importante ressaltar que tanto a qualidade da ?gua quanto a sua quantidade e regularidade de fornecimento s?o fatores determinantes para o surgimento de doen?as no ser humano. Portanto, utilizou-se o estudo epidemiol?gico do tipo ecol?gico, de natureza quantitativa, a fim de avaliar o consumo de ?gua da chuva e a incid?ncia de diarreia em crian?as menores de 5 anos de idade: as expostas, as quais utilizam sistemas de capta??o de ?gua de chuva do telhado e que ? armazenada em cisternas para fins pot?veis, compostas por 111 crian?as da cidade de V?rzea da Ro?a?Ba; e as n?o expostas, as quais utilizam ?gua da rede p?blica de abastecimento, compostas, tamb?m, por 111 crian?as da cidade de Baixa Grande-Ba. Os indicadores de sa?de adotados foram diarreia referida e mensurada, durante um per?odo de 90 dias. Foram aplicados formul?rio, planilha e ficha de observa??o de campo junto ?s fam?lias e crian?as participantes da pesquisa. A an?lise dos dados obtidos da diarreia referida e da mensurada apresentou uma associa??o significante entre os epis?dios de diarreia na amostra total de crian?as estudadas e na distribui??o espacial onde ocorreram as maiores concentra??es. As crian?as que beberam ?gua de chuva apresentaram maior risco, em percentual e tempo de ocorr?ncia, de ter epis?dios de diarreia do que as crian?as que bebem ?gua da rede p?blica, por?m com uma diferen?a n?o muito acentuda. A incid?ncia nas crian?as que consomem ?gua da chuva armazenada em cisternas foi de 11,1%, e de 5,8% nas fam?lias que bebem ?gua da rede p?blica.
286

Spatial distribution of heavy metals in surface marine sediments in the Mediterranean region

Kampezidou, Dimitra January 2015 (has links)
Several scientific articles were mainly reviewed from Umeå’ s university database in order to determine the distribution, degree of contamination, and the sources of 7 selected heavy metals (Cr, Pb, Cu, Zn, Cd, Hg, Ni) in surface sediments along the coasts of the Mediterranean Sea. The Enrichment factor (EF) was used as pollution indicator to evaluate the extent of metal contamination in all the investigated areas. According to Abrahim and Parker (2008) the EF is defined as the ratio of the determined metal to Al (or Fe) in the sample divided by the ratio of background metal to background Al (or Fe) ratio. According to the results of this study, EF values for Cr, Pb, Cu, Cd and Ni presented an upward trend along the west to east shoreline of the Mediterranean sea, whereas Zn and Hg EF values showed a downward trend along this region. Cr generally exhibited no enrichment in places to the west (EF<1.5) whereas in the eastern side displayed moderate enrichment (EF=1.95). Pb EF values showed moderate enrichment (EF=5) along the western section of the sea, whilst in the eastern part revealed significant enrichment (5.45). Zn pollution levels were minimal (EF=1.6) in places to the west and moderate (EF=2.2) to the east. The enrichment for Cd was considered moderate in the western part of the basin and significant in the eastern section. These heavy metals distribution can be explained by the fact that different inputs (mainly due to anthropogenic activities) from the inshore environment may take place in each area of the sea. However, Cu and Ni presented the same degree of pollution (moderate) in the whole sea, presumably indicating similar Cu and Ni inputs from the terrestrial environment. However, conclusions for Hg were not possible to be drawn as the collected data were not sufficient.
287

Estrutura espacial das comunidades de Ephemeroptera HAECKEL, 1896 (Insecta) em riachos da Serra da Mantiqueira e da Serra do Mar, Estado de São Paulo / Spatial structure in assemblages of Ephemeroptera Haeckel, 1896 (insecta) in streams of Serra da Mantiqueira and Serra do mar, State of São Paulo

Siegloch, Ana Emilia 26 March 2010 (has links)
Este estudo teve como objetivos, i) investigar a composição taxonômica das duas vertentes da Serra da Mantiqueira (Parque Estadual de Campos do Jordão e Região de Pindamonhangaba) e da Serra do Mar (Núcleos Santa Virgínia e Picinguaba), com base na coleta de larvas e alados, ii) analisar quais as escalas espaciais (mesohábitat, riacho, vertente e serra) que melhor estruturam as comunidades de Ephemeroptera e iii) identificar e quantificar as variáveis ambientais que influenciam as comunidades de larvas de Ephemeroptera. Considerando o esforço conjunto de todos os métodos de coleta foram registradas oito famílias 33 gêneros e 21 espécies, das quais oito famílias 28 gêneros e 18 espécies na Serra da Mantiqueira e sete famílias 30 gêneros e 15 espécies no Parque Estadual da Serra do Mar. As duas serras apresentaram uma porção bastante significativa da riqueza taxonômica do Brasil, 41% e 45% dos gêneros e 80% e 70% das famílias, respectivamente. A alta riqueza registrada no estudo pode ser relacionada à metodologia de coleta empregada que abrangeu a coleta de larvas e alados e explorou diversos mesohábitats e riachos. Considerando todo o modelo hierárquico, houve variação significativa da riqueza e abundância das comunidades entre as quatro vertentes e os mesohábitats pedra e folha/corredeira. No entanto, a maior variação ocorreu entre as réplicas de um mesmo mesohábitat, refletindo o padrão de distribuição agregada das comunidades de Ephemeroptera. A maior riqueza foi encontrada no mesohábitat pedra/corredeira e na vertente que abrange o Núcleo Santa Virgínia. A ordenação mostrou tendência de segregação das amostras de cada vertente e tipo de mesohábitat. Essa tendência de segregação foi corroborada pela análise de variância multivariada (Permanova). Assim, a estrutura espacial das comunidades de larvas de Ephemeroptera parece predita pelos fatores ambientais da escala local ligadas aos mesohábitats e pelos fatores de maior magnitude da escala regional, associados às vertentes. A Análise de Redundância (RDA) evidenciou a altitude, condutividade elétrica, temperatura da água e Resumo Geral 10 largura como as variáveis ambientais locais que mais contribuíram para explicar a estrutura das comunidades. No entanto, as variáveis ambientais locais explicaram apenas 19,3% da variabilidade na abundância dos gêneros, 7,9% da variabilidade foi explicada pelas variáveis ambientais indissociáveis da matriz geográfica, 23,4% foi explicada pela posição geográfica dos riachos e 49,4% permaneceu inexplicada. Os resultados encontrados nesse estudo destacam a contribuição semelhante das variáveis ambientais locais e da posição geográfica dos riachos na estruturação das comunidades, indicando que além das variáveis ambientais locais os processos biológicos contagiosos, como dispersão, também influenciaram a estrutura das comunidades de larvas de Ephemeroptera na região estudada / The purpose of this study was to i) inventory the taxonomic composition the mayfly fauna, larva and adult, in two slopes of the Mantiqueira Mountains (Campos do Jordao State Park and Pindamonhangaba Region) and of the Serra do Mar (Santa Virginia and Picinguaba Nuclei), located in São Paulo State, ii) analyze the spatial scales (mesohabitat, stream, slope and mountain) that best explain the spatial structure of Ephemeroptera assemblages and iii) identify and quantify the environmental variables that affects the communities of Ephemeroptera larvae. In all, 8 families, 33 genera and 21 species of Ephemeroptera were recorded. In the Serra da Mantiqueira 8 families, 28 genera and 18 species were found and in the Serra do Mar, 7 families, 30 genera and 15 species. Both mountains had a very significant portion of the genera reported to Brazil (41% and 45% of genera and 80% and 70% of families, respectively). The high Ephemeroptera richness in the areas may be related to the sampling methodology used, that included the collection of larvae and adults and explored several kinds of mesohabitats and streams. Considering the entire hierarchical model, there was a significant variation in both richness and abundance of the assemblages among the four slopes and between stone and leaf mesohabitats. Moreover, the highest variation in richness and abundance occurred among the samples from the same mesohabitat, which reflects the clumped distribution pattern of the assemblages of Ephemeroptera. Stone was the mesohabitat with the highest estimated richness, similarly Santa Virgínia Nucleus was the slope with highest estimated richness. The ordination showed a trend of segregation of samples from slopes and mesohabitats, this trend was confirmed by multivariate analysis of variance (Permanova). Thus, the spatial structure of the assemblages seems predicted by environmetal factors of local scale related to mesohabitats and the features of regional scale, associated with slopes. The Redundancy Analysis (RDA) showed elevation, electrical conductivity, water temperature and width as the local environmental variables that contributed most to explain the spatial structure of communities. However, local enrironmental factors explained only 19.3% of the data variability, 7.9% of the General Abstract 12 data variability was explained by environmental variables inseparable from the geographical matrix, 23.4% was explained by the geographical location of streams and 49.4% remained unexplained. The results of this study showed the similar contribution of local environmental variables and the geographic location in the community structure, indicating that the biological processes, as dispersal, also influenced the structure of the assemblages of Ephemeroptera larvae.
288

Structure and restoration of natural secondary forests in the Central Highlands, Vietnam

Bui, Manh Hung 02 December 2016 (has links)
Introduction and objectives In Vietnam, the forest resources have been declining and degrading severely in recent years. The degradation has decreased the natural forest area, changed the forest structure seriously and reduced timber volume and biodiversity. From 1999 to 2005, the rich forest area has decreased 10.2%, whereas the poor secondary forest has increased dramatically by 20.7%. Forest structure plays an important role in forestry research. Understanding forest structure will unlock an understanding of the history, function and future of a forest ecosystem (Spies, 1998). The forest structure is an excellent basis for restoration measures. Therefore, this research is necessary to contribute to improving forest area and quality, reducing difficulties in forest management. The study also enhances the grasp of forest structure, structure changes after harvesting and fills serious gaps in knowledge. In addition, the research results will contribute to improving and rescuing the poor secondary forest and restoring it, approaching the old-growth forest in Vietnam. Material and methods The study was conducted in Kon Ka Kinh national park. The park is located in the Northeastern region of Gia Lai province, 50 km from Pleiku city center to the Northeast. The park is distributed over seven different communes in three districts: K’Bang, Mang Yang and Đăk Đoa. Data were collected from 10 plots of secondary forests (Type IIb) and 10 plots of primeval forests (Type IV). Stratified random sampling was applied to select plot locations. 1 ha plots were used to investigate gaps. 2000 m2 plots were used to measure overstorey trees such as diameter at breast height, total height, crown width and species names. 500 m2 subplots were used to record tree positions. For regeneration, 25 systematic 4 m2 subplots were established inside 1 ha plots. After data were collected in the field, data analyses were conducted by using R and Excel. Firstly, some stand information, such as density, volume and so on, was calculated, and then descriptive statistics were computed for diameter and height variables. Linear mixed effect models were applied to analyze the difference of diameter and height and to check the effect of random factor between the two forest types. Diameter and height frequency distributions were also generated and compared by using permutational analysis of variance (PERMANOVA). Non-linear regression models were analyzed for diameter and height variables. Similar analyses were implemented for gaps. Regarding spatial point patterns of overstorey trees, replicated point pattern analysis techniques were applied in this research. For biodiversity, some calculations were run such as richness and biodiversity indices, comparison of biodiversity indices by using linear mixed models and biodiversity differences between two forest types tested again by permutational analysis of variance. In terms of regeneration, some analyses were implemented such as: height frequency distribution generation, frequency difference testing, biodiversity indices for the regeneration and spatial distribution checking by using a nonrandomness index. Results and discussion After analyzing the data, some essential findings were obtained as follows: Hypothesis H1 “The overstorey structure of secondary forests is more homogeneous and uniform than old-growth forests” is accepted. In other words, the secondary forest density is about 1.8 times higher than the jungle. However, the volume is only 0.56 times as large. The average diameter and height of the secondary forest is smaller by 5.71 cm and 3.73 m than the old-growth forest, respectively. Linear mixed effect model results indicate that this difference is statistically different and the effect of the random factor (Section) is not important. Type IIb has many small trees and the diameter frequency distribution is quite homogeneous. The old-growth forest has more big trees. For both forest stages, the height frequency distribution is positively skewed. PERMANOVA results illustrate that the frequency distribution is statistically different between the two forest types. Regression functions are also more variant and diverse in the old-growth forest, because all standard deviations of the parameters are greater there. Gap analysis results indicate that the number of gaps in the young forest is slightly higher, while the average gap size is much smaller. The gap frequency distribution is statistically different between the two types. In terms of the spatial point pattern of overlayer trees, the G-test and the pair correlation function results show that trees distribute randomly in the secondary forest. In contrast, the spatial point patterns of trees are more regular and diverse in the old-growth forest. The spatial point pattern difference is not significant, and this is proved by a permutational t-test for pair correlation function (pcf). Envelope function results indicate that the variation of pcf in young forests is much lower than in the primary forests. Hypothesis H2 “The overstorey species biodiversity of the secondary forest is less than in the old-growth forest” is rejected. Results show that the number of species of the secondary forest is much greater than in the old-growth forest, especially richness. The richness of the secondary forest is 1.16 times higher. The Simpson and Shannon indices are slightly smaller in the secondary forest. The average Simpson index for both forest stages is 0.898 and 0.920, respectively. However, the difference is not significant. Species accumulation curves become relatively flatter on the right, meaning a reasonable number of plots have been observed. Estimated number of species from accumulation curves in two forest types are 105 and 95/ha. PERMANOVA results show that number of species and proportion of individuals in each species are significantly different between forest types. Hypothesis H3 “The number regenerating species of the secondary forest is less and they distribute more regularly, compared to the old-growth forest” is rejected. There are both similarities and differences between the two types. The regeneration density of the stage IIb is 22,930 seedlings/ha, greater than the old forest by 9,030 seedlings. The height frequency distribution shows a decreasing trend. Similar to overstorey, the richness of the secondary forest is 141 species, higher than the old-growth forest by 9 species. Biodiversity indices are not statistically different between two types. PERMANOVA results indicate that the number of species and the proportion of individuals for each species are also not significantly different from observed forest types. Nonrandomness index results show that the regeneration distributes regularly. Up to 95% of the plots reflect this distribution trend. Hypothesis H4 “Restoration measures (with and without human intervention) could be implemented in the regenerating forest” is accepted. The investigated results show that the secondary forest still has mother trees, and it has enough seedlings to restore. Therefore, restoration solutions with and without human intervention can be implemented. Firstly, forest protection should be applied. This measure is relevant to national park regulations in Vietnam. Rangers and other related organizations will be responsible for carrying out protection activities. These activities will protect forest resources from illegal logging, grazing and tourist activities. Environmental education and awareness-raising activities for indigenous people is also important. Another measure is additional and enrichment planting. It should focus on exclusive species of the overstorey in Type IIb or exclusive species of the primary forest. Selection of these species will lead to species biodiversity increase in the future. This also meets the purpose of the maximum biodiversity solution. Conclusion Forest resources play a very important role in human life as well as maintaining the sustainability of ecosystems. However, at present, they are under serious threat, particularly in Vietnam. Central Highland, Vietnam, where forest resources are still relatively good, is also threatened by illegal logging, lack of knowledge of people and so on. Therefore, it needs the hands of the people, especially foresters and researchers. Through research, scientists can provide the knowledge and understanding of the forest, including the structure and forest restoration. This study has obtained important findings. The secondary forest is more homogeneous and uniform, while the old-growth forest is very diverse. Biodiversity of the overstorey in the secondary forest is more than the primary. The number of regenerating species in the secondary forest is higher, but other indices are not statistically different between two types. The regeneration distribute regularly on the ground. The secondary forest still has mother trees and sufficient regeneration, so some restoration measures can be applied here. Findings of the study contribute to improve people’s understanding of the structure and the structural changes after harvesting in Kon Ka Kinh national park, Gia Lai. That is a key to have better understandings of the history and values of the forests. These findings and the proposed restoration measures address rescuing degraded forests in Central Highland in particular and Vietnam in general. And further, this is a promising basis for the management and sustainable use of forest resources in the future.:TABLE OF CONTENTS ACKNOWLEDGEMENTS I TABLE OF CONTENTS III LIST OF FIGURES VIII LIST OF TABLES XI LIST OF ABBREVIATIONS XII SUMMARY XIII CHAPTER I: INTRODUCTION 1 1.1. The decline of natural forest resources, orientation of difficulty and development in Vietnam 1 1.1.1. Decline of forest resources 1 1.1.2. Difficulties in forestry management 1 1.1.3. Management strategies 2 1.2. Forest structure role 3 1.3. Forest restoration in Vietnam 4 1.4. Importance of old-growth and secondary forests 4 1.5. Aims, scope and hypotheses 6 1.5.1. Aims 6 1.5.1.1. General objective 6 1.5.1.2. Specific objective 6 1.5.2. Scope 6 1.5.3. Hypotheses 6 CHAPTER II: LITERATURE REVIEW 8 2.1. Tropical forest structure analysis 8 2.1.1. History 8 2.1.1.1. Overstorey 8 2.1.1.2. Regeneration 12 2.1.2. Structural attributes of tropical forests 13 2.1.2.1. Overstorey 14 a. Analyzed attributes 14 b. Relevant attributes to this study 15 2.1.2.2. Regeneration 21 2.2. Secondary tropical forest restoration 22 2.2.1. Strategies for secondary forest restoration 23 2.2.1.1. Protection and natural recovery 24 2.2.1.2. Natural regeneration management 24 a. Growing conditions and yield of desirable regeneration improvement 24 b. Desirable regeneration assistance 25 2.2.1.3. Accelerated Natural Regeneration (ANR) 25 2.2.1.4. Enrichment planting 25 2.2.1.5. The framework species method 26 2.2.1.6. Maximum diversity planting method 26 CHAPTER III: MATERIAL 27 3.1. Natural conditions of the study area 27 3.1.1 Geographic location, boundaries and area of Kon Ka Kinh national park 27 3.1.2. Topography, geology and soil 28 3.1.2.1. Topography 28 3.1.2.2. Geology and soil 29 3.1.3. Climate and hydrology 30 3.1.3.1. Climate 30 3.1.3.2. Hydrology 31 3.2. Vegetation in Kon Ka Kinh national park 31 3.2.1. The area of land use types 31 3.2.2. Plant biodiversity 33 3.2.3. The flora and forest vegetation 33 3.2.3.1. Flora 33 3.2.3.2. Forest vegetation 34 3.2.3.3. History of forest exploitation in the park 35 3.3. Assessing the natural conditions and vegetation of the park 37 3.4. Population, ethnicity and labor 38 3.4.1. Population 38 3.4.2. Labor and ethnicity 39 3.4.3. Poverty status 40 3.5. Forest resources classification 40 3.5.1. The Loeschau’s classification system 40 3.5.2. The relationship between forest types with development phases 42 CHAPTER IV: METHODOLOGY 45 4.1. Plot establishment method 45 4.2. Data collection method 47 4.2.1. Data collection for overstorey stem maps 47 4.2.1.1. Tree data collection 47 4.2.1.2. Tree positions 50 4.2.1.3. Gap inventory 51 4.2.2. Data collection for regeneration 52 4.3. Data analysis method 55 4.3.1. Applied methods for the upper layer 55 4.3.1.1. Stand information 55 a. Calculation for each tree 55 b. Calculation for a stand 55 4.3.1.2. Descriptive statistics for height and diameter variables 56 a. Central tendency 56 b. Dispersion and variability 56 c. Measures of distribution shape 57 4.3.1.3. Linear mixed-effects analysis 59 a. Applications with this study and data arrangement 60 b. Homoscedasticity checking 61 c. Checking autocorrelation 63 d. Checking normal distribution of the residuals 66 e. Model selection and information summary 67 4.3.1.4. Frequency distribution 68 a. Generating frequency distributions 68 b. Frequency distribution difference testing 69 4.3.1.5. Diameter-height regression analysis 70 a. Used function forms 70 b. Theoretical calculations 71 c. Model selection 73 4.3.1.6. Gap analysis 74 a. Descriptive statistics for gaps 74 b. Calculating the gap area proportion for each forest type 74 c. Gap size frequency distribution 74 d. Gap size frequency distribution difference testing 75 4.3.1.7. Spatial point patterns of tree species 75 a. Applications 76 b. Tree density analysis 77 c. Testing for randomness 78 d. Comparing point pattern variation 83 e. Testing the difference between forest types 84 4.3.1.8. Overstorey tree species diversity analysis 85 a. Richness and species importance value index (SIVI) 85 b. Species diversity index 86 c. Species accumulation curve 88 d. Biodiversity index comparison 88 e. Tree species diversity comparison 89 4.3.2. Regenerating tree storey structure analysis 90 4.3.2.1. Frequency distribution of regeneration 90 4.3.2.2. Height frequency distribution difference testing 91 4.3.2.3. Biodiversity indices for regeneration 91 4.3.2.4. Biodiversity index comparison by using LMM 91 4.3.2.5. Regeneration species diversity comparison 91 4.3.2.6. Regeneration spatial distribution checking 91 a. Nonrandomness index 91 b. Nonrandomness index value comparison 92 CHAPTER V: RESULTS 93 5.1. Overstorey structure analysis results 93 5.1.1. Stand information 93 5.1.2. Descriptive statistics results 95 5.1.3. Linear mixed effect model results 97 5.1.3.1. Box plots for the diameter and height variables 97 5.1.3.2. Model analysis and adaptation 97 5.1.3.3. Model parameter estimation 100 5.1.4. Frequency distributions 101 5.1.4.1. Frequency distribution results for both types 101 5.1.4.2. Frequency distribution difference 107 5.1.5. Diameter-height regression results 107 5.1.5.1. Estimated parameters 107 5.1.5.2. Model selection 110 5.1.5.3. Regression charts 110 5.1.6. Gap analysis 116 5.1.6.1. Gap descriptive information 116 5.1.6.2. Gap area ratio 117 5.1.6.3. Gap size frequency distribution 117 5.1.6.4. Gap size frequency distribution difference testing results 120 5.1.7. Spatial distribution analysis 120 5.1.7.1. Density testing results 120 5.1.7.2. Randomness checking results 122 5.1.7.3. Variation difference between two types 123 5.1.7.4. Point pattern difference testing between two types 124 5.1.8. Overstorey species diversity analysis results 125 5.1.8.1. Richness, SIVI and biodiversity indices 125 5.1.8.2. Biodiversity index comparison by using LMM 127 5.1.8.3. Tree species diversity comparison 127 5.2. Regeneration storey structure analysis results 128 5.2.1. Height frequency distribution 128 5.2.2. Height frequency distribution difference testing 130 5.2.3. Biodiversity index for regeneration 131 5.2.4. Biodiversity index difference comparison 133 5.2.5. Regeneration species diversity comparison 133 5.2.6. Regeneration spatial distribution 134 5.2.6.1. Nonrandomness index results 134 5.2.6.2. Nonrandomness index value testing results 134 CHAPTER VI: DISCUSSION 135 6.1. Overstorey structure differentiation 135 6.1.1. Structure and spatial distribution difference 135 6.1.1.1. Stand information 135 6.1.1.2. Statistical descriptions for diameter and height 136 6.1.1.3. Diameter and height growth difference testing by linear mixed effect models 137 6.1.1.4. Frequency distribution dissimilarity 138 6.1.1.5. Diameter-height regression 139 6.1.1.6. Canopy gaps 140 6.1.1.7. Spatial distribution patterns 141 6.1.2. Biodiversity distinction of overstorey trees 143 6.2. Regeneration dissimilarity 145 6.2.1. Density and frequency distribution 145 6.2.2. Biodiversity indices 146 6.2.3. Spatial distribution of regeneration 147 6.3. Proposing restoration measures 147 6.4. Improved points in this research 150 CHAPTER VII: CONCLUSION AND RECOMMENDATION 152 7.1. Conclusion 152 7.2. Suggestions for further research 154 REFERENCES 156 APPENDIX 180
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Vliv orografie na prostorové rozložení silných srážek na severovýchodě ČR / Effects of orography on spatial distribution of heavy precipitation in the north-east of the Czech Republic

Průchová, Kateřina January 2010 (has links)
The dissertation deals with the influence of orography on the spatial distribution of heavy precipitation in the territory of the northeast Moravia and Silesia. The area was chosen because of the specific distribution of daily precipitation for heavy rainfall events in the past and also in May 2010. Cases of heavy rainfall for the period 1961 - 1995 are balanced with morphometric characteristics in the place and in the surrounding the station, defineted in face of direction air flow. For the calculation of the direction air flow are used data from 850 hPa level from reanalysis ERA-40, topographic characteristics are calculated by ArcGIS and they are correlated with the rain gauge data from stations ČHMÚ. The results show us that only the altitude does not have effect on the spatial distribution of precipitation, but it should be think over more topographic parameters. During the north and partially during the west air flow, where the precipitation are mostly from the stratiform clouds, appears a stronger orography influence on the measurement and on the spatial distribution, if we consider the morphometric characteristics behind the station in the direction of air flow. The case of south and east air flow showed us a weaker orography effect, which can be perhaps explained by a higher part of...
290

Rozmístění imigrantů po území Itálie / Spatial Distribution of Immigrants in Italy

Pavelková, Lenka January 2011 (has links)
This thesis focuses on spatial distribution of immigrants in Italy. In the beginning, it presents three migration theories used in the thesis (network theory, Human Capital Model, institutional theory) and related hypothesis for the research. Then it summarises the migration history of Italy since the Second World War and the current situation. After that, the tex proceeds to the examination of the spatial distribution of immigrants in Italy. The examination is done in two ways. First, there is analysis of statistical data by correlation analysis which tries to find factors which explain the immigrants' distribution in Italy. Second is the analysis of the results of a survey done in Trieste, Italy, between March and June 2011 among the two largest groups of immigrants living in the province of Trieste (those with citizenship of Serbia and Romania). The main results are that one of the most important factors for the immigrants' distribution are the job opportunities and better earnings for themselves and for their families. Interestingly, the network theory wasn't supported by the research, especially for Romanians who seem to prefer provinces with less Romanians (and foreigners in general) already present. After the analysis, the results are compared with the situation in the Czech Republic. For further...

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