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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.
131

Estrutura, biomassa arbórea e composição florística de ilhas de mata da savana de Roraima, norte da Amazônia brasileira

Margarita Maria Almanza Jaramillo 26 February 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Ecossistemas florestais dispersos em matrizes de savana da Amazônia vêm sofrendo vários tipos de impactos antropogênicos, em especial fogo recorrente e extração seletiva. O estoque de carbono na biomassa destes sistemas e a sua contribuição como mitigador dos impactos gerados pelo aquecimento global são pobremente conhecidos. O objetivo deste estudo foi estimar a biomassa arbórea viva acima do solo em ilhas de mata (fragmentos florestais) antropizadas da savana de Roraima, norte da Amazônia Brasileira. Foram avaliados os seguintes fatores: dimensão do fragmento, estrutura florestal (tomando como base a posição no gradiente: borda e interior) e as características físicas e químicas do solo. Foi realizado um inventário florestal em 12 ilhas de mata escolhidas aletoriamente, levando em consideração três categorias dimensionais (k = 3): ilhas grandes (20-60 ha), médias (10-20 ha) e pequenas (< 10 ha). Em cada categoria foram estudadas quatro ilhas (n = 4) e, em cada ilha foram estabelecidas subparcelas (76 no total). Todos os indivíduos arbóreos com diâmetro à altura do peito (DAP) &#8805; 10 cm foram inventariados. A altura total de cada indivíduo foi estimada visualmente. O cálculo da biomassa arbórea viva acima do solo (AGB) para todos os indivíduos inventariados foi realizado pelo método indireto a partir de uma equação alométrica. Foram observados 1087 indivíduos de 112 espécies arbóreas (incluindo morfoespécies) pertencentes a 29 famílias botânicas. Pouteria surumuensis Baehni (Sapotaceae) foi a espécie mais abundante em todas as categorias dimensionais. Ilhas de maior dimensão possuem maior abundância de espécies de crescimento tardio e clímax, enquanto espécies pioneiras predominam em ilhas de menor dimensão. A biomassa arbórea não diferiu entre a borda e o interior dos fragmentos, independente da dimensão. Contudo, a biomassa arbórea para fragmentos grandes (469,9 Mg ha-1), médios (357,1 Mg ha-1) e pequenos (206,4 Mg ha-1) diferiu significativamente (ANOVA; Tukey0,05), indicando que fragmentos maiores possuem maior AGB. A biomassa arbórea viva não apresentou relação com as características físicas e químicas do solo. A conclusão deste estudo é que biomassa arbórea viva acima do solo das ilhas de mata da savana de Roraima varia em função da dimensão do fragmento, mas independe da posição no gradiente (borda interior), não indicando relação significativa com estrutura física ou fertilidade do solo. / Forest ecosystems dispersed in matrices of Amazonian savannas have been suffering many types of anthropogenic impacts, in particular recurrent fire and selective logging. The carbon stock in the biomass of these systems and its contribution to mitigation of impacts generated by global warming are poorly known. The aim of this study was to estimate the living above ground biomass in anthropized forest islands (forest fragments) in the Savanna of Roraima, Northern Brazilian Amazon. Environmental factors were evaluated: the fragment dimension, forest structure (based on the position in the gradient: edge and interior) and the physical and chemical soil characteristics. A forest inventory was carried out in 12 forest fragments randomly chosen, taking into account three-dimensional categories (k = 3): large islands (20-60 ha), medium (10-20 ha) and small (< 10 ha). In each category were studied four fragments (n = 4) and in each fragment subplots were established (76 in total). All individuals with tree diameter at breast height (DBH) &#8805; 10 cm were inventoried. The total height of each individual was estimated visually. Living above ground biomass was calculated for all individuals inventoried using indirect method (allometric equation). One thousand and eight seven (1087) individuals were observed of 112 tree species (including morphospecies) belonging to 29 botanical families. Pouteria surumuensis Baehni (Sapotaceae) was the most abundant species in all dimensional categories. Forest islands with larger dimensions have higher abundance for both late-growing and climax species, while smaller islands were dominated by pioneer species. The living above ground biomass did not differ between the edge and the interior of fragments regardless of dimension. However, the forest biomass of large (469.9 Mg ha-1), medium (357.1 Mg ha-1) and small (206.4 Mg ha-1) fragments differed significantly (ANOVA; Tukey0.05), indicating that larger fragments have higher living above ground biomass. The living above ground biomass did not present any relationship with the physical and chemical soil characteristics. The conclusion of this study is that living above ground biomass of forest islands in the Savanna of Roraima varies depending on the fragment size, but is independent of the position in the gradient (edge-interior), indicating no significant relationship with the structure or soil fertility.
132

Biomassa de raízes em diferentes fitofisionomias de savana em Roraima

Jhonson Reginaldo Silva Santos 30 July 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O objetivo desse trabalho foi estimar a biomassa de raízes em diferentes fitofisionomias de savana em Roraima. O trabalho foi realizado entre Junho de 2009 e Fevereiro de 2010 em duas áreas onde estão estabelecidas as grades do PPBio em Roraima: Campo Experimental Água Boa (Embrapa/RR; 616 ha e 22 parcelas amostrais), e Campus Cauamé (UFRR; 498 ha e 12 parcelas amostrais). O estoque de biomassa de raízes foi obtido com extrator específico em profundidades de 0-10, 10-20, 20-30, 30-40 e 40-50 cm em quatro subamostras em cada uma das parcelas. A quantificação da biomassa aérea também foi obtida com a finalidade de se estabelecer relações root:shoot. A média de estoque total, sem considerar a fitofisionomia ou classe de solo, foi de 21,39 Mg.ha-1 no Água Boa e 15,35 Mg.ha-1 no Cauamé, com predominância de raízes finas (Ø < 2mm): 99,7% e 98,33%, respectivamente. A maior média encontradas foi para savana gramíneo-lenhosa / campo limpo (Sg-cl) com 22,07 Mg.ha-1 no Água Boa e savana gramíneo-lenhosa / campo sujo com 16,56 Mg.ha-1 no Cauamé. O mosaico Sg+Sp foi a fitofisionomia que apresentou a maior relação root:shoot: 1 : 3,13 (Água Boa) e 1 : 5,64 (Cauamé). O estoque de biomassa por classes de solo apresentou maior valor em GLEISSOLO com 23,82 Mg.ha-1 no Água Boa e 17,78 Mg.ha-1 para o LATOSSOLO VERMELHO no Cauamé. Considerando a conjunção de fitofisionomias com classes de solos (fitopedounidade), o GLEISSOLO (campo limpo) apresentou maior média de estoque de biomassa (23,82 Mg.ha-1 no Água Boa). No Cauamé, a fitopedounidade com maior média foi LATOSSOLO VERMELHO (campo sujo) com 17,78 Mg.ha-1. Os resultados obtidos sugerem variação do estoque de biomassa condicionado a disponibilidade hídrica do solo e do tipo fitofisionomico, sendo necessários novos estudos para melhor compreensão da distribuição da biomassa radicular nas áreas de savana em Roraima. / The objective of this study was to estimate the root biomass in different savanna phytophysionomies of Roraima. The study was conducted between June 2009 to February 2010 in two areas where are established grids of the PPBio: Campo Experimental Água Boa (Embrapa-RR; 616 ha and 22 sampling plots) and the Campus Cauamé (UFRR; 498 ha and 12 sample plots). The stock of root biomass was obtained by a specific extractor in five soil layers: 0-10, 10-20, 20-30, 30-40 and 40-50 cm on four replicates in each sampling plots. Aboveground biomass was also obtained in order to establish root:shoot relations. The average of total stock without considering phytophysionomic type or soil class was 21.39 Mg.ha-1 in Água Boa and 15.35 Mg.ha-1 in Cauamé. The root diameter class more predominant was fine roots (Ø < 2 mm), with 99.7% and 98.33%, respectively. Considering the phytophisionomic type, it was obtained a better average in Grassland / campo limpo (Sg-cl) with 22.07 Mg ha-1 in the Água Boa, and Grassland / campo sujo (Sg-cs) with 16.56 Mg ha-1 in Cauamé. The mosaic Sg+Sp was the phitophisionomy which showed higher root:shoot; 1 : 3,13 (Água Boa) and 1 : 5,64 (Cauamé). The root biomass stock for soil classes showed higher level in GLEISOL (23.82 Mg ha-1; Água Boa) and RED LATOSOL (17.78 Mg ha-1; Cauamé). Considering the conjunction between phytophysionomic types and soil classes (Phytopedounit), GLEISOL / campo limpo was the higher average root biomass stock (23.82 Mg ha-1 in the Água Boa). For the Cauamé area, the highest average was the RED LATOSOL / campo sujo, with 17.78 Mg ha-1. The results suggest variation in root biomass conditioned to the both water available in the soil and phytophisionomic type. However, its necessary more studies to have a better understanding on root biomass distribution in the Roraima savanna.
133

Marãnã Bödödi - a territorialidade Xavante nos caminhos do Ró / Marãnã Bödödi the Xavante\'s territoriality on the way of Ró

Maria Lucia Cereda Gomide 05 March 2009 (has links)
Entende-se que a reprodução física e cultural dos povos indígenas em seus territórios, em grande parte está condicionada à demarcação de territórios indígenas, que considere a territorialidade e o modo de vida indígena. No entanto não foi o caso do território Xavante. A demarcação do território indígena Xavante em diversas terras indígenas ilhadas e, portanto, separadas entre si, causou inúmeros conflitos socioambientais alterando seu modo de vida. Reconstruir o território indígena que foi erroneamente e intencionalmente fragmentado e demarcado em ilhas é um grande desafio político para o povo Xavante. O território indígena compreende as relações de apropriação do espaço que possui diversas dimensões como política, cultural, simbólica, e cosmológica de um determinado povo indígena. Por outro lado, Terra indígena é uma categoria produzida no processo político-jurídico do Estado. Assim, a partir do contato entre os povos indígenas e a sociedade envolvente, há um conflito, pois existem distintas lógicas espaciais em confronto. O recorte geográfico desta pesquisa são as terras indígenas Xavante no leste matogrossense, com destaque para a bacia hidrográfica do rio das Mortes (MT). Este recorte deve-se a importância geográfica desta unidade territorial para se discutir o território indígena e principalmente pela importância cultural, simbólica e ambiental deste rio para o povo Xavante. Considera-se a importância do contínuo para analisar as terras Xavante, Sangradouro, São Marcos, Areões e Pimentel Barbosa, nessa bacia que tem como eixo de ligação o rio das Mortes, denominado Öwawe (rio Grande) pelos Xavante. A pesquisa trata, portanto, da fragmentação do território indígena, demarcado em ilhas e a (re) construção da territorialidade por meio do Marãnã Bödödi, o caminho das matas. O conceito de Marãnã Bödödi contempla várias dimensões entre elas a relação Xavante com os cerrados e sua espiritualidade, a sua territorialidade nos caminhos do Ró (cerrados, mundo). / This research deals with the Xavante territory and territoriality. Is well known that physical and cultural reproduction of the indigenous people is mostly conditioned to their territory delimitation, which contemplates the territoriality and the indigenous way of life. That was not the case when it comes to the Xavante\'s territory. The delimitation of the Xavante\'s indigenous territory in many patchy lands caused various social and environmental problems changing their way of life. To rebuild the indigenous territory that was wrongly and intentionally fragmented and divided in islands is a great political challenge for the Xavante people. The indigenous territory regards the relations of the space appropriation which has different aspects such as politics, symbology and cosmology of a certain indian tribe. On the other hand, the indigenous land is a category created in the legal-political process of the State. Therefore, from the contact between the indigenous people and the surrounding society, there\'s a conflict, once there are different spacial logical in the confrontation. The geographical approach of this research are the Xavante\'s indigenous land in the east of Mato Grosso state, specially the Mortes River basin (MT). This cut is due to the geographical importance of this territorial unity to discuss the indigenous territory and mainly for its cultural, symbolic and environmental importance of this river to the Xavante people. The importance of the continuum Xavante, Sangradouro, São Marcos, Areões and Pimentel Barbosa, in this basin which has as a connection axis the Mortes River, named Öwawe (the big river) by the Xavante. Therefore, the research deals with the fragmentation of the indigenous territory, set in islands and the territory (re)construction through the Marãnã Bödödi concept, which regards many dimensions, such as the relation between the Xavante and the brazilian savanna and their spirituality. Finally, is discussed the Xavante territoriality on the way of Ró (savannas, the world) in a historical and environmental approach.
134

Composição e sazonalidade de borboletas frugívoras no cerrado, com ênfase na relação fenológica entre Eunica bechina (Nymphalidae: Biblidinae) e sua planta hospedeira Caryocar brasiliense (Caryocaraceae) / Composition and seasonality of fruit-feeding butterflies in the cerrado savanna, with emphasis on the phenological relationship between Eunica bechina (Nymphalidae: Biblidinae) and its host plant Caryocar brasiliense (Caryocaraceae)

Silva, Danilo Germano Muniz da 19 August 2018 (has links)
Orientadores: Paulo Sérgio Moreira Carvalho de Oliveira, André Victor Lucci Freitas / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-19T22:18:27Z (GMT). No. of bitstreams: 1 Silva_DaniloGermanoMunizda_M.pdf: 3019678 bytes, checksum: c1529979d45609cac62d29ee7dd332fe (MD5) Previous issue date: 2011 / Resumo: Em muitos ambientes tropicais, estações chuvosas se alternam com períodos de seca. A estação seca é um período de menor disponibilidade e qualidade nutricional de folhas, sendo, portanto, um período desfavorável para insetos herbívoros e gerando as oscilações sazonais em suas populações. O cerrado é um bioma neotropical sazonal, que inclui formações de savana (cerrado sensu stricto), e onde o clima se caracteriza por uma estação quente e chuvosa de outubro a abril e uma fria e seca de maio a setembro. A produção de folhas novas se concentra geralmente na estação chuvosa, tornando este um período favorável para muitos insetos herbívoros tais como as borboletas. Em seu estágio larval, as borboletas são herbívoros vorazes cujas populações comumente oscilam de acordo com a disponibilidade de folhas adequadas ao desenvolvimento dos imaturos. Borboletas podem ser divididas funcionalmente em duas guildas: as que se alimentam em sua forma adulta do néctar de flores, e aquelas que se alimentam dos líquidos oriundos de frutos em decomposição, seiva de árvores, carcaças de animais e excrementos. As espécies do segundo grupo são conhecidas como borboletas frugívoras. A guilda de borboletas frugívoras tem sido amplamente utilizada em estudos de ecologia de comunidades devido à facilidade de captura usando armadilhas com iscas de fruta fermentada, e a relativa facilidade de identificação. Entretanto, poucas vezes esta comunidade foi estudada em ambientes abertos, e raramente em trabalhos envolvendo sazonalidade. Nesta dissertação exploramos a sazonalidade das borboletas frugívoras do cerrado sensu stricto em dois capítulos. No primeiro abordamos a composição da comunidade, suas alterações ao longo do ano bem como suas oscilações de abundância. A maior abundância de borboletas ocorreu no meio da estação chuvosa, enquanto o pico de riqueza ocorreu ao final desta estação. Satyrini foi o grupo mais abundante na estação chuvosa (principalmente Yphthimoides manasses), enquanto na estação seca foi Biblidinae (principalmente Hamadryas februa). No segundo capítulo analisamos em detalhe a relação fenológica entre a borboleta Eunica bechina e sua planta hospedeira, o pequizeiro Caryocar brasiliense. Esta planta possui nectários extraflorais atrativos para formigas, que patrulham a planta e atacam as larvas de E. bechina. Observamos a maior ocorrência de larvas no início da estação seca, quando ocorreu a maior produção de folhas. Ovos e larvas estavam presentes em quase todos os meses de amostra, exceto no final da estação chuvosa. Propomos que este seja um período de inatividade reprodutiva na espécie, devido à baixa disponibilidade de folhas jovens / Abstract: In many tropical environments, rainy and dry seasons alternate. The dryer season has decreased leaf availability and the nutritional quality of leaves is also low - thus it is an unfavorable period for herbivorous insects and generates seasonal oscillations in their populations. The cerrado is a neotropical seasonal biome characterized by a hot/rainy and a cold/dry season. Leaf production is generally concentrated in the rainy season, which is the favorable period for herbivorous insects such as butterflies. In its larval stage, butterflies are voracious and specialized herbivores, and their populations commonly oscillate according to the availability of adequate leaves for immature feeding. Butterflies can be categorized in two functional guilds according to the food resources utilized by the adults: one group feeds on flower nectar, whereas another group of species feed on the liquids from rotting fruits, carcasses and excrements, and also plant sap. The latter group is known as fruit-feeding butterflies. Fruit-feeding butterfly guild has been widely used in studies of community ecology because they are easily captured using traps with fermented fruit, and also easily identified. Surprisingly, however, fruit-feeding butterflies have rarely been studied in seasonal, open environments. In this dissertation we investigated the seasonality of fruit-feeding butterflies in the cerrado sensu stricto. In the first chapter we decribe the composition of the community, changes through the year, and oscillations in its abundance. The greatest abundance occurred in the mid rainy season, while richness peaked at the late rainy season. Satyrini was the most abundant group in the rainy period (mainly Yphthimoides manasses), whereas Biblidinae (mainly Hamadryas februa) was more common in the dry season. In the second chapter we analyze in detail the phenological relationship between the butterfly Eunica bechina and its hostplant Caryocar brasiliense. The larvae feed only on the young leaves of C.brasiliense that bear extrafloral nectaries, which attract ants that patrol the plant and attack E. bechina larvae. We observed the larger occurrence of larvae in the early rainy season, when most young leaves are produced. Eggs and larvae where present at almost all sampling months, except in the late rainy season. We suggest that this is a period of reproductive inactivity in the species, due to the low availability of young leaves / Mestrado / Ecologia / Mestre em Ecologia
135

Parametrização e modelagem do balanço hidrico em sistema de plantio direto no cerrado brasileiro

Silva, Fernando Antonio Macena da 07 July 2005 (has links)
Orientador: Hilton Silveira Pinto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-03T21:59:17Z (GMT). No. of bitstreams: 1 Silva_FernandoAntonioMacenada_D.pdf: 6475935 bytes, checksum: 246f935053cc089136cbc1a9488498c7 (MD5) Previous issue date: 2004 / Doutorado / Agua e Solo / Doutor em Engenharia Agrícola
136

Development and Validation of a Remote Sensing Model to Identify Anthropogenic Boreholes that Provide Dry Season, Refuge Habitat for <i>Anopheles</i> Vector Mosquitoes in Sub-Saharan Africa

Kukat, James Pkemoi 16 June 2016 (has links)
A lack of surveillance systems is an impediment to public health intervention for perennial vector-borne disease transmission in northern tropical savanna region of Kenya. The population in this area are mostly poor nomadic pastoralists with little acquired functional immunity to Plasmodium falciparum, due to infrequent challenges with the parasite. A common characteristic in tropical savanna climatic zone is the availability of riverbeds that have anthropogenic boreholes that provide malaria vector mosquitoes, such as Anopheles gambiae s.l and Anopheles funestus, with aquatic refuge habitats for proliferation and endemic transmission to proximity human households during the dry-season. Unfortunately, currently there have been no entomological investigations employing field or remotely sensed data that can characterize and model anthropogenic borehole habitats focusing on the dry-land ecology of immature Anopheles mosquitoes in sub-Sahara Africa. The goal of this investigation was three-fold: (I) to employ WorldView-3 (0.31 meter spatial resolution) visible and near infra-red waveband sensor data to image sub-Saharan land cover associated with vector-borne disease transmission; (II) to remotely identify anthropogenic boreholes in three riverbeds that were surveyed to determine whether they provide malaria vectors with refuge habitat and maintain their population during the dry season in Chemolingot, Kenya, and (III) to obtain a radiometric/spectral signature model representing boreholes from the remotely-sensed data. The signature model was then interpolated to predict unknown locations of boreholes with the same spectral signature in Nginyang Riverbed, Kenya. Ground validation studies were subsequently conducted to assess model’s precision based on sensitivity and specificity tests.
137

Ecology and morphology of the Kalahari tent tortoise, Psammobates oculifer, in a semi-arid environment

Keswick, Tobias January 2012 (has links)
Philosophiae Doctor - PhD (Biodiversity and Conservation Biology) / Southern Africa harbours one-third of the world's Testudinid species, many of which inhabit arid or semi-arid areas, but ecological information on these species is scant. I studied the habitat, morphology and ecology of Kalahari tent tortoises over 13 months in semi-arid Savanna at Benfontein farm, Northern Cape Province, South Africa. In order to allow continuous monitoring of individuals, I attached radiotransmitters to males and females, split equally between two habitats, sites E (east) and W (west), with apparent differences in vegetation structure. Results of the study were based on data obtained from 27 telemetered tortoises and 161 individuals encountered opportunistically. Female Kalahari tent tortoises were larger than males and the sex ratio did not differ from 1:1. Based on person-hours to capture tortoises, the population appeared to have a low density, with more time required to capture a juvenile (35 hours) than an adult (10-11 hours). The frequency distribution of body size ranges was indicative of recruitment. Relative age, based on annuli counts, suggested that males were younger than females, perhaps because males as the smaller sex are more predation-prone than females. Linear relationships between annuli counts and shell volume indicated that, after reaching sexual maturity, female body size increased faster in volume than did male body size, possibly because a larger volume may enhance female reproductive success. Body condition differed between sites, sexes and among seasons. The hot and dry summer may account for low summer body condition, whereas vegetation differences and size effects, respectively, may account for the low body condition of tortoises in site W and in males. Site E was sandy with grasses, particularly Schmidtia pappophoroides, being the prevalent growth form. This habitat resembled a Savanna vegetation type Schmidtia pappophoroides – Acacia erioloba described for a neighbouring reserve. Site W was stonier, dominated by shrubs, and was reminiscent of Northern Upper Karoo vegetation (NKu3). Neither site resembled Kimberley Thornveld (SVk4), the designated vegetation type of the area. Differences in substrate and grazing intensity may have contributed to site vegetation differences. Rainfall had an important influence on seasonal vegetation. Short grass abundance correlated with rainfall and annual plants sprouted after spring rain. Refuge use changed according to season and sex. Males selected denser refuges than females did, perhaps because males were smaller and more vulnerable to predation and solar heat. Tortoises selected sparse, short grass as refuges in cool months, probably to maximise basking whilst remaining in protective cover. During hot periods, mammal burrows were preferred to vegetation as refugia. The smaller males spent more time in cover than females, which may be related to predator avoidance or thermoregulation. Females spent more time basking than males, perhaps due to their larger size and to facilitate reproductive processes. Tortoises did not brumate, but through a combination of basking, and orientation relative to the sun in their refuges, managed to attain body temperatures that allowed small bouts of activity. Body temperature for active tortoises was similar among seasons, and was higher for more specialised active behaviours, such as feeding and socialising, than for walking. Increased activity by males in spring could relate to mating behaviour while females were more active in autumn, when they foraged more than males, perhaps due to the high cost of seasonal reproductive requirements. Males displaced further per day than did females, but home range estimates did not differ between sexes. Annual home range estimates varied substantially among individuals: 0.7–306 ha for minimum convex polygons and 0.7–181 ha for 95% fixed kernel estimates. The ability to cover large areas would assist tortoises in finding resources, e.g., food, in an area where resource distribution may be patchy. Differences among seasonal home ranges and movements probably reflect seasonal climatic change; activity areas shrinking when temperatures were extreme. In order to assess the effects of a semi-arid environment on the morphology of P. oculifer, I compared its morphology to that of its ‘cool-adapted’ sister taxon Psammobates geometricus, using live and museum specimens. Both P. oculifer and P. geometricus are sexually dimorphic and differences between the two species could indicate environmental or sexual selection effects, or a combination of the two. The shorter bridge length, which allowed more leg space, and wider front feet in P. oculifer cohorts probably represent traits for manoeuvring in a sandy habitat, while wider heads in P. oculifer possibly relate to interspecific differences in diet. The flatter shell in female P. oculifer, relative to P. geometricus, may represent a trade-off between space for reproductive structures, e.g., eggs, and the need to fit into small refuges, e.g., mammal burrows. Male P. oculifer had wider shells, more space around their hind legs, and wider hind feet than P. geometricus males had, all characteristics which may assist males to fight and mate in a sandy environment. / South Africa
138

Compara??o flor?stica e diversidade das ?reas core de savanas ?cerrado? e disjun??es do leste da Bahia, Brasil

Reis, Alessandra Terezinha Chaves Cotrim 17 November 2014 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-01-25T21:49:47Z No. of bitstreams: 1 TESE_Alessandra Cotrim.pdf: 9069866 bytes, checksum: 892f9788ca4b0cbbf4794de6292ed4d2 (MD5) / Made available in DSpace on 2016-01-25T21:49:47Z (GMT). No. of bitstreams: 1 TESE_Alessandra Cotrim.pdf: 9069866 bytes, checksum: 892f9788ca4b0cbbf4794de6292ed4d2 (MD5) Previous issue date: 2014-11-17 / This paper aims to study the floristic of areas of Brazilian Savannas in state of Bahia and compares them to the physiognomies present in Coastal Plain in east of Bahia which are considered disjoint cerrado. The methodology of this work consisted of establish five sampling areas in the state of Bahia: 1) Savanna physiognomy in the west of Bahia; 2) In the Chapada Diamantina; 3) In the Coastal Plain; 4) Restinga in the northern littoral of Bahia; 5) Restinga in the southern littoral of Bahia. The sampling areas were performed using the point centered quarter method, being in each area were sampled 100 points 20m far between distributed in 10 transects with 10 points each, considering the degree of conservation in each study area. All woody individuals with DBH ? 3 cm closer to each point were sampled in that survey totaling 400 individuals per area. A sum of 2.000 individuals were sampled. The Shannon index (H') was used to estimate the diversity of each area. The Jaccard index of similarity (cluster method) was used to determine the floristic similarity between transects and study areas. Were sampled 78 species in the Western Savanna formations distributed in 31 families; estimated the diversity by the Shannon index H' = 3,61 to 3,93; 68 species in the Chapada Diamantina Savanna formations distributed in 30 families and estimated the diversity by the Shannon index between 3,49 to 3,45; 83 species in Coastal Plains distributed in 38 families wich estimated the diversity by H? = 3,46 to 3,89; 73 and 69 species in the restingas in the Northern and Southern littoral distributed in 36 and 33 families; estimated the diversity by the Shannon index H'=3,61 to 3,97 and H? = 3,68 to 3,85. Cluster analysis indicated that the floristic similarity found between coastal plain in the east of the State of Bahia and restinga formations (coast) indicating floristic relationship between the areas. The Savanna formations in the west of Bahia and Chapada Diamantina presented 30% of similarity. There by the analysis of this work showed more evident relationship of the floristic in Coastal Plains to the Atlantic forest physiognomy therefore these areas should be treated as Atlantic forest physiognomy related including all legal aspects of conservation and forest management provided by law n? 11.428/2006 and resolutions of CONAMA. / Este trabalho teve por objetivo determinar e comparar flor?sticamente as ?reas de Savanas encontradas na Bahia e compar?-las ?s fisionomias encontradas sobre os Tabuleiros Costeiros no Leste da Bahia, consideradas ?reas de Cerrado disjuntos. Para condu??o do trabalho foram estabelecidas cinco ?reas de amostragens na Bahia, sendo: 1) fisionomias Sav?nicas localizados na regi?o Oeste; 2) na Chapada Diamantina; 3) nos Tabuleiros Costeiros; 4) Restingas noLitoral Norte; 5) Restingas do LitoralSul. A amostragem nas ?reas foram realizadas atrav?s do m?todo de pontos-quadrantes, sendo alocados em cada ?rea amostral 100 pontos equidistantes em 20 m, distribu?dos em 10 transec??es, com 10 pontos cada, respeitando-se o grau de conserva??o de cada ?rea estudada. Em cada quadrante, foram amostrados os indiv?duos lenhosos com DAS ?3 cm, mais pr?ximos de cada ponto, perfazendo um total de 400 indiv?duos por ?rea, perfazendo um total de 2.000 indiv?duos amostrados. A diversidade de cada ?rea analisada foi estimada pelos ?ndices de Shannon-Wiener(H?). Para determina??o da similaridade flor?stica entre as ?reas estudadas foram realizadas an?lises de agrupamentos a partir do ?ndice de similaridade de Jaccard (J). Nas fisionomias sav?nicas da regi?o Oeste do Estado foram amostradas78 esp?cies, distribu?das em 31 fam?lias; a diversidade estimada pelo ?ndice de H? = 3,61 a 3,93; nas fisionomias sav?nicasda Chapada Diamantina 68 esp?cies, distribu?das em 30fam?lias, a diversidade estimada pelo ?ndice de Shannon-Wiener (H?) variou de 3,49 a 3,45; para os Tabuleiros Costeiros 83 esp?cies, distribu?das em 38 fam?lias, a diversidade estimada pelo ?ndice H? = 3,46 a 3,89; para as Restingas do Litoral Norte e Sul, obteve-se respectivamente, 73 e 69 esp?cies distribu?das em 36 e 33 fam?lias, a diversidade estimada pelo ?ndice de Shannon-Wienervariou deH? = 3,61 a 3,97 e H? = 3,68 a 3,85,respectivamente. As an?lises de agrupamento apontaram similaridades flor?sticas entre os Tabulerios Costeiros no Leste do Estado com as fisionomias de restingas (no Litoral), indicando rela??o flor?stica entre as ?reas.J?as fisionomias sav?nicas do Oeste e da Chapada Diamantinaapresentaram 30% de similaridade. Assim, pelas an?lises deste estudo evidenciou-se uma maior rela??o flor?stica dos Tabuleiros com as fisionomias de Mata Atl?ntica, portanto, estas ?reas devem ser tratadas como fisionomias relacionadas a Mata Atl?ntica, inclusive quanto aos aspectos legais de conserva??o e manejo, previstos na Lei n? 11.428/2006 e Resolu??es do CONAMA.
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Pomar de sementes por mudas em Eucalyptus camaldulensis e Hymenaea stigonocarpa : uma opção para o melhoramento e a conservação genética em espécies arbóreas exóticas e nativas /

Zaruma, Darlin Ulises Gonzalez January 2020 (has links)
Orientador: Mario Luiz Teixeira de Moraes / Resumo: As espécies florestais possuem grande importância econômica, pois oferecem diversos produtos fundamentais para a sociedade, mas dada a impossibilidade de se separar ações de melhoramento das de conservação de recursos genéticos, técnicas como os testes combinados de progênies e procedências, tanto para espécies exóticas ou nativas, visam a seleção de árvores pelo valor genético e a transformação dos experimentos em PSM (pomares de semente por mudas). Os pomares de sementes são os vetores de produção de sementes de alta qualidade genética, que ligam as atividades de melhoramento das árvores às práticas de conservação. No anterior contexto, sementes de polinização aberta provenientes de uma população base de Eucalyptus camaldulensis e de um fragmento de Cerrado com Hymenaea stigonocarpa, foram coletadas e plantadas na Faculdade de Engenharia de Ilha Solteira (FEIS/UNESP), em Selvíria-MS. O objetivo deste trabalho foi verificar a variação genética e ganhos genéticos a partir do desbaste dentro de progênies de E. camaldulensis aos 10 anos de idade e estimar parâmetros genéticos populacionais, por meio de marcadores moleculares do tipo microssatélites para H. stigonocarpa, com vistas ao melhoramento genético e conservação, respectivamente. Para análise quantitativa, os caracteres altura (ALT), diâmetro a altura do peito (DAP), volume (VOL), densidade básica (DBM) e sobrevivência (SOB) foram utilizados. Assim os valores observados para sobrevivência (>90%) de E. camaldulensis indic... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Forest species are of great economic importance, as they offer several fundamental products for society, but given the impossibility of separating actions to improve those from the conservation of genetic resources, techniques such as the combined testing of progenies and provenances for both exotic and native species, aim at the selection of trees by their genetic value and the transformation of the experiments in PSM (seed orchards by seedlings). Seed orchards are the vectors of seed production of high genetic quality, which link tree improvement activities to conservation practices. In the previous context, open pollination seeds from a base population of Eucalyptus camaldulensis and a fragment of Cerrado with Hymenaea stigonocarpa, were collected and planted at the Faculty of Engineering of Ilha Solteira (FEIS/UNESP), in Selvíria-MS. The objective of this work was to evaluate the genetic variation and genetic gains from thinning within E. camaldulensis progeny at 10 years of age, and to estimate population genetic parameters, using microsatellite molecular markers for H. stigonocarpa, with a view to genetic improvement and conservation, respectively. For quantitative analysis, the characters height (H), diameter at breast height (DBH), volume (VOL), basic density (DBM) and survival (SUR) were used, thus the values observed for survival (> 90%) indicate good adaptation of the species to the place. Estimates considered to be of high magnitude were obtained for the coefficie... (Complete abstract click electronic access below) / Doutor
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Impact du couvert arboré et herbacé sur le cycle de l'azote : cas de la savane de Lamto / Impact of tree and grass cover on the nitrogen cycle : case of the Lamto savanna

Srikanthasamy, Tharaniya 21 September 2018 (has links)
Une savane est définie par la coexistence entre des arbres et des Poacées. Dans la savane de Lamto en Côte d’Ivoire, l’espèce dominante de Poacée est connue pour inhiber la nitrification et avant mon étude, l’impact des arbres sur la nitrification était très mal connu. L’étape de la nitrification est conduite par deux différentes communautés, les archées et les bactéries nitrifiantes ayant le gène amoA. Le but de cette étude est de comprendre l’impact de ces deux types de végétaux sur le cycle de l’azote, notamment sur les communautés nitrifiantes et également de comprendre l’impact de la saisonnalité et du passage du feu sur ces processus. Des échantillonnages ont été réalisés sous les Poacées et les arbres à Lamto durant les saisons humides et sèche et également avant et après le passage du feu. Cela a mis en évidence plusieurs effets : (i) les Poacées dominantes de la savane inhibent la nitrification, (ii) les arbres dominants stimulent la nitrification, (iii) les archées nitrifiantes son prédominantes dans cette savane et elles contribueraient majoritairement à la nitrification, (iv) la saisonnalité à un impact direct sur les abondances et l’activité des micro-organismes du sol (l’activité transcriptionelle des archées nitrifiantes diminuent en saison humide), (v) le feu a un effet indirect sur les communautés microbiennes du sol par son impact sur les caractéristiques physico-chimiques des sols, notamment il diminue l’activité des archées nitrifiantes. Enfin, la dénitrification est supérieure sous les arbres que sous les Poacées. Cette étude a permis de mieux comprendre les interactions entres les bactéries et archées nitrifiantes, la végétation et la saisonnalité. / A savanna is defined by the coexistence between trees and grasses. Savannas represent 12-13% of continental surfaces. In the Lamto savanna in Ivory Coast, the dominant grass species inhibits nitrification (the transformation of ammonium into nitrate) and the impact of trees on nitrification before this study was not known. Nitrification is conducted by two different communities. The archaea nitrifiers that have the amoA-AOA gene and bacteria nitrifiers that have the amoA-AOB gene. The aim of this study is to analyse the impacts of both plant types on nitrogen cycling, particularly on the nitrifier communities, and understand the impact of seasonality and fire on these processes. Sampling was conducted under grasses and trees in the Lamto savanna during the wet and dry seasons and also before and after the fire. This study has highlighted for the first time different effects including: (i) the dominant savanna grasses inhibit nitrification, (ii) dominant trees stimulate nitrification, (iii) the archaea nitrifiers are predominant in this savanna and they are mainly responsible for nitrification in this ecosystem, (iv) seasonality has a direct impact on the abundances and activities of soil microorganisms and the wet season reduced archaea nitrifier transcriptional activities, (v) fire has an indirect impact on soil microbial communities due to its impacts on soil physico-chemical characteristics: it decrees the abundance of archaea nitrifiers. In addition, denitrification is higher under trees than grasses. This study permitted to better understand the interactions between nitrifiers, vegetation and seasons.

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