No description available.

Larval development and reproduction of 19 species of Central Amazonian fish (five cichlids, two siluriforms, one osteoglossiform and 11 characiforms) were studied over two years. Most species spawn during the flooding season. The cichlids, the siluriforms and two species of characiform are nest spawners, reproducing in the littoral areas of the floodplain. The osteoglossiform is a mouth-brooder. The remaining characiforms spawn in the river channels and show no parental care. Two main strategies explain 90% of the variability of reproductive traits found among the 19 species. The first strategy is used by riverine spawners (characiforms). They have high fecundity , high to very high reproductive expenditure (calories per spawn per wet weight of female) and spawn once a year during a short season. Their eggs vary in size from 0.06 to 0.3 mg and have intermediate to high calorific value. The second strategy is used by the cichlids and two species of characiforms. They have low fecundity, low reproductive expenditure, long spawning season, multiple spawnings per season and some of them show parental care. Their eggs vary in size from 0.4 to 1.2 mg and have an intermediate calorific content. The other three species show distinct combinations of reproductive traits, but have as common feature a high reproductive expenditure, a short annual spawning season and parental care. Patterns of larval development are correlated with egg size and adult spawning sites. Egg size explained most of variability of larval body size at hatching, pectoral fin bud, eye pigmentation, jaw formation, swim bladder inflation, onset of swimming, first feeding and maximum size attained with exclusively endogenous feeding. The pattern of blood circulation of the larvae was correlated with the spawning sites. Larvae of riverine spawners are small, utilize yolk efficiently and are relatively resistant to starvation. Newly hatched larvae of riverine spawners seem to be very sensitive to physico-chemical conditions of the floodplain lakes, but by the first feeding stage they develop some resistance to the low availability of oxygen. Larvae of littoral spawners are large, utilize yolk less efficiently, and seem to be resistant to low concentrations of oxygen. The resistance of larvae to oxygen deficiency is correlated with the development of the larval respiratory system. It is suggested that egg size of riverine spawners was selected to optimize the distance of the dispersal of the larvae in a range of floodplain lakes. Conversely, egg size of floodplain spawners seemed to be selected to optimize larval survival in the spawning lake. The results are further discussed in relation to life history models.

Made available in DSpace on 2015-04-22T22:03:59Z (GMT). No. of bitstreams: 1 liliane costa.pdf: 2039909 bytes, checksum: 304662a64ebbfc1ca1e2e887c297fc21 (MD5) Previous issue date: 2012-05-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The history of recent occupation of the Amazon is directly related to religious cultures meet, socially sustained by the material and spiritual worlds separate, lived defining ethos. It is worth mentioning Christianity as a major religious movements in the region introduced the principle of Catholicism and later by Protestantism. It s possible to see the influence that the church had on the lives of residents, becoming the family after one of the most important social institutions and acting field today remains in the process of forming new communities, playing practical messianic evangelization and colonization. Between the coastal communities of Jaiteua de Cima, Manacapuru / AM, are the churches (evangelical and Catholic) that define the socio-political space, because the process of implementation of these churches on the site is directly related to the history of the formation of social communities Nossa Senhora do Perpetuo Socorro and Assembleia de Deus. Are the churches on the site that occupy the central space, so that study on religious life deserves to be a phenomenon that modifies symbolically the political, social, spatial and temporal perception among coastal communities. The characteristics of these changes are more visible, for example, the construction of churches and creating a space for the patron saint, the replacement of the companion to use the term "peace of the Lord", the importance level for a family to another, types of leisure activities such as soccer practice with more or less intensity. Therefore, the religious life works as one of the most important assurance mechanisms of power between families in that it brings together and dominate the community, thus becoming a symbolic power. We want this work to analyze the mode of occupation of these religious communities from the perspective of sociological theories of Max Weber, Emile Durkheim, Peter Berger, Pierre Bourdieu, Heraldo Maues and Gedeon Alencar. Show the possibility of comparing the theoretical model constructed by the authors with the observation pointed to empirical reality. / A história da ocupação recente da Amazônia está diretamente relacionada com o encontro de culturas religiosas sustentadas socialmente por mundos materiais e espirituais distintos definidores do ethos vivido. Cabe destacar o Cristianismo como um dos principais movimentos religiosos introduzido na região, a princípio, pelo Catolicismo e mais tarde pelo Protestantismo. É possível perceber a influência que a igreja exerceu sobre a vida dos moradores, tornando-se depois da família uma das mais importantes instituições sociais. E na atualidade permanece exercendo domínio no processo de formação de novas comunidades, reproduzindo práticas messiânicas de evangelização e colonização. Entre as comunidades ribeirinhas de Jaiteua de Cima, Manacapuru/AM, são as Igrejas (evangélica e católica) que delimitam o espaço sociopolítico, pois o processo de implantação destas Igrejas no local está diretamente relacionado com a história da formação social das comunidades Nossa Senhora do Perpétuo Socorro e Assembléia de Deus. São as igrejas locais que ocupam o espaço de centralidade. Por isso, esse estudo sobre a vida religiosa merece destaque pois trata-se de um fenômeno que modifica simbolicamente as relações políticas e sociais de percepção espaço-temporais entre as comunidades ribeirinhas. As características mais visíveis dessas mudanças são, por exemplo, as construções de igrejas, a criação de um espaço próprio para o Santo Padroeiro, a substituição do termo compadre pelo termo paz do Senhor , o nível de importância de uma família para outra e os tipos de lazer, como a prática do futebol. Portanto, a vida religiosa funciona como um dos mais importantes mecanismos de garantia do poder entre as famílias, na medida em que aglutina e domina a comunidade, constituindo-se em um poder simbólico. Pretendemos neste trabalho analisar o modo de ocupação religiosa destas comunidades sob a ótica das teorias sociológicas de Max Weber, Émile Durkheim, Peter Berger, Pierre Bourdieu, Heraldo Maués e Gedeon Alencar e mostrar a possibilidade de confrontar o modelo teórico construído pelos autores com a observação empírica da realidade apontada.

Using ERA40 and independent observations, I assess how well Amazon surface water budget is estimated. ERA40 basin wide annual precipitation (P) agrees with observations showing an underestimation of 10%, whereas runoff (R) is underestimated by a larger margin (~25%). Observed residual of precipitation and runoff (P-R) is better estimated by ERA40 P-R than actual ET which includes soil moisture nudging. Nudging is necessary during the dry season to produce realistic ET and compensate for low soil moisture recharge during the wet season. Insufficient recharge may be caused by: underestimation of rainfall amount and intensity; a shallow root layer in the model that does not represent the deep soil water reservoir of the Amazonian forest. The physical links between changes in wet season onset and synoptic scale systems are investigated in the second part of my work. A delayed wet season onset is consistent with a decreasing number of cold air incursion (CAI) days in southern Amazon during 1979-2001. CAI variability in southern Amazon is related to SST in the tropical Pacific and Indian Oceans. The first mode of co-variability shows that during El Nio (La Nia) a strong (weak) subtropical jet stream over South America is related to decreased (increased) CAI days during SON. The second mode shows warm western Indian Ocean also related to strong subtropical jet stream. The absence a well defined subpolar jet stream, favors the northward displacement of transient waves into central South America, but shows little response in southern Amazon. CAI days reconstructed from the first and second modes do not present any significant trend in southern Amazon. CAI days reconstructed from the third mode of co-variability reproduces SON observed trend. This mode describes negative (positive) anomalies in CAI days associated with cold (warm) SST anomalies, anomalous wavetrain in the tropical Pacific and Walker Cell displacement that are unfavorable (favorable) to the incursion of CAI into southern Amazon. This mode's temporal evolution correlates with the Pacific Decadal Oscillation (PDO), suggesting that its recent gradual signal shift reflected on the interannual response of southern Pacific atmospheric patterns, hence on the behavior of transients propagation.

Thesis (Ph. D.)--University of Chicago, Dept. of Sociology, August 2003. / Includes bibliographical references. Also available on the Internet.

This research examines how the Kandozi indigenous group governs access to fish and timber, how access contributes to their well-being, and if the Kandozi’s natural resource use and socio-ecological system are sustainable. The Kandozi occupy a biodiverse tropical forest in the northern Peruvian Amazon with lakes and seasonally flooded areas. This indigenous group has livelihoods that are dependent upon securing access to natural resources that contribute to their well-being; hence it represents a good case study to investigate access and its relation with social-ecological sustainability. Access is defined here as the ability to derive benefits from natural resources. The analysis of sustainability was done by integrating research on both access and well-being. Multiple methods and a comparative examination of access to fish and timber were used to explore historical processes that shape access. The analysis of qualitative data on well-being and quantitative data based on income from fishing activities in 2009, helped evaluate if the Kandozi benefited from the use of resources and clarified the evolution of their quality of life. Hypotheses regarding how spatiality shapes access and how sustainability depends upon access to natural resources were tested. Results indicate that factors such as heterogeneity, kinship, land tenure, the legal framework and knowledge all shape access to natural resources. Spatial and temporal heterogeneity in particular is a critical factor because it determines resource availability. Furthermore, this study shows how benefits from the use of resources contribute to the Kandozi’s perception of well-being, defined by them as living without worries, which includes meeting economic, social and cultural needs. Results from this study indicate that perceptions of well-being depend on human values and change over time, consequently the sustainability of the social-ecological system fluctuates. This research concludes that sustainability of this and similar systems are dependent upon the moment at which the analysis is done, because of the changing needs of people over time. This study demonstrates that the range of relations and interactions among different processes that shape access, and the historically contingent characteristic of access and its evolution over time, help better understand complex social ecological systems. / text

The rate of recombination and parasite load of species of anuran from Peruvian Amazonia were examined to test the idea that recombination functions to diversify progeny in order to resist the continual counter-adaptation of parasites. The anurans were found to be hosts to over 32 species of macroparasite, as well as a wide variety of protistan and moneran parasites. It was found that a combination of three variables (diet, habitat, abundance), together with host body size accounted for a substantial proportion of the variation in mean parasite richness and parasite species distribution among host species. The relationship between parasites and ecology was found to be independent of host phylogeny. The demonstration of substantial environmental heterogeneity in parasitization predicates that a positive relationship between parasite richness and recombination should be found in this case. This prediction was supported by the data: highly parasitized species of anuran had higher rates of recombination. This is the first study to demonstrate a direct positive relationship between recombination (rather than sex) and parasites.

Most of the Amazonia is covered by the lowland evergreen rain forest (LERF) formation. A small proportion of the region (5-6% in total) is covered by heath forest, which is particularly common in the Rio Negro basin on Spodosols - white sand soils with a layer of mor humus. The smaller facies of heath forest (SHF) is called 'Camping' in Brazil and often lacks the mor humus; the taller facies (TBF) is called 'Campinarana'. The present study was made in central Amazonia, on a gradient from SHF through THF to well developed LERF. Soil, vegetation, and nutrient dynamics were studied in three 50 m x 50m plots in each type of forest. Litterfall was measured during one year and litter standing crop was measured three times a year. Three decomposition experiments, using bagged leaf litter, were made using leaves of two common species from the heath forests and one from the LERF. Fertiliser addition experiments in the field and in the laboratory were carried out to determine the potential nutrient limitations for plants in the three forest types. Annual litterfall was highest in the dry season and was 3.8 t ha-1 yr-1 in the SHF, 6.3 t ha-1 yr-1 in the THF and 7.8 t ha-1 yr-1 in the LERF. The rates of weight loss of the enclosed leaf litter were most rapid in the LERF and slowest in the SHF. The leaves of the LERF species Clitoria racemosa decomposed faster than those of the heath forest species. Fine roots penetrating litter-bags differed significantly among forest types and leaf species, and increased the decay rates. There were no significant differences in decomposition rates between the wet and dry season experiments. Significant differences in the release of chemical elements were observed: higher immobilization of iron and aluminium in the LERF; higher potassium and copper release in THF; and lower calcium, but higher boron release rates in SHF. Significantly higher immobilization of iron and aluminium (mainly in LERF) was found in bags penetrated by fine roots, while release of magnesium, calcium, manganese and zinc was significantly increased by fine roots, particularly in the TI-IF. Leaf mass loss and nutrient release were mostly controlled by abiotic factors in the SHF, but organisms were more active in the THF and LERF. Diplopoda were the dominant decomposers, particularly in the THF. Fertiliser addition showed an overall positive effect of liming, especially in heath forest soils. Nitrogen and phosphorus additions did not induce higher biomass production, while calcium chloride addition invariably induced a high mortality. 11÷ ion toxicity, together with a higher concentration of soil phenolics are suggested as causes of the poor growth in the heath forests, but in the SHF, where it lacks mor humus, limitation by nutrients, especially basic cations, may occur.

The Amazon region is one of the richest areas on the planet in terms of its biodiversity and natural resources. The large scale harvesting of trees in this region is a relatively new activity, and it is uncertain whether the exploitation of timber species will result in depletion of forest genetic resources. To examine this, I have assessed levels of inbreeding, gene flow, and genetic diversity in populations of Amazonian forest trees undergoing logging. Because of their high variability within populations, microsatellite genetic markers were chosen for the study, and it was verified through an initial sampling experiment that this class of markers is sufficiently stable within somatic tissue of large and long-lived trees such that population studies could be undertaken with them. By sampling adult trees and seed progenies at several microsatellite loci, high levels of gene flow and low levels of inbreeding were found within populations of Sextonia rubra and Carapa guianensis, two important insect-pollinated Amazonian forest tree species. Comparing seed progeny collected before versus after selective logging of a population of Carapa guianensis, no measurable evidence was found that that the population genetic dynamics is impacted by logging. In particular, levels of inbreeding, gene flow, and population substructure were the same before and after logging. Comparing different populations distributed over the Amazon basin, a phylogeographical structure in the chloroplast DNA of Carapa guianensis that corresponds to major tributaries of the Amazon river was discovered, suggesting that seed dispersal through rivers may contribute to genetic connectivity among populations. Overall, the results of this thesis suggest that the large effective population sizes, the high levels of gene flow, and the low levels of inbreeding in exploited Amazonian tree populations may allow them to counteract potential negative genetic impacts of selective logging, at least at the levels of harvesting carried out during this study, and for the Carapa guianensis population investigated.

Thesis (Ph.D)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2009. / Committee Chair: Fu, Rong; Committee Member: Dickinson, Robert E.; Committee Member: Nenes, Athanasios; Committee Member: Webster,Peter J.; Committee Member: Yu, Hongbin. Part of the SMARTech Electronic Thesis and Dissertation Collection.