This study explores the present forest management systems in place and their impact on the genetic diversity and the ecology of Hymenaea courbaril in the Brazilian Amazon forest, specifically in the Tapaj6s National Forest. As part of the Dendrogene Project (EMBRAPAIDFID), this study has as its main objective to evaluate the effects of Reduced Impact Logging on the species' genetic variability and ecological processes and to predict the likely impacts in the short- and long-term. The specific objectives of this thesis are to verify the quality of the. forest inventory used in RIL at Tapaj6s National Forest, to determine impacts of harvesting on forest structure and the species' reproductive population and spatial pattern, to determine Hymenaea . courbarifs genetic diversity, spatial genetic structure, pollen flow and mating system, and assess the impact of logging on these processes, and finally to infer on the impact of logging on Hymenaea courbarifs sustainability in the long-term using the modelling software Eco-gene. The results demonstrate the critical importance of correct botanical identification for the sustainability of forest management. The assessed forest inventory was highly inaccurate in relation to botanical identification and severely underestimated trees diversity which might compromise the capacity of accurately analysing species' spatial distribution and forest timber stock. The results also show that current forest management practices have negative impacts on the H. courbaril species including a reduction in reproductive population, spatial distribution and demography. The results of logging scenarios run through Eco-gene suggest that the harvesting cycle for Hymenaea courbaril should be between 120 and 150 years in order to reach pre-logging levels. More importantly, the model suggests that current logging practice strongly affect the species' population both ecologically and genetically in the long-term. These impacts were also observed for scenarios up to 90 years unless logging intensity is very low (10 - 30%). Moreover, the model results indicate that the current practise is not economically viable as the volume to be logged in future harvests will be acutely reduced. The results of this thesis provide forest planning and management with specific scientific criteria from a heavily logged species which can help to more effectively manage not only H. courbaril, but can also be used to move toward the sustainability of other tree species in the Amazon forest.

The aim of this smdy v,'as to assess the genetic diversity of Sitka spruce seedling populations as produced by commercial growers and to detennine what effects the propagation technologies ofrooted cuttings and somatic embryogenesis had on genetic diversity. Seedling populations ,,,ere produced consisting of one hundred seedlings' from each of three families of Washington provenance material and from each of three families of Queen Charlotte Islands provenance. Rooted cutting populations were produced from twelve cuttings from each of fifty randomly selected plants [rom each of the six families. Somatic embryogenesis derived populations (emblings) were produced and fifty populations were provided by Coillte from the three Washington provenance families which represented the maximum number of cell lines produced by a successful commercial grower. Significant phenotypical differences betwe.en zygotic seedlings were found at both family and provenance level after 19 months of grov.1h. All 300 genotypes were able to produce rooted cuttings indicating that no significant loss of genetic diversity in cuttings from two-year-old trees. Seven pairs of microsatellite primers were multiplexed to amplify polymorphic microsatellite DNA loci from needle samples of seedlings and emblings. Capillary electrophoresis of the products yielded data which were analysed according to the Infinite Allele Model and Stepwise Mutation Model. No significant differences were found, using either mutation model, between the genetic diversity values (observed heterozygosity, gene diversity, allelic richness and inbreeding coefficient (Fis)) for the seedling populations and somatic embryogenesis derived populations. A low level of microsatellite variation was found to occur within mature individual trees and within somatic embryogenesis derived populations. The extent of microsatellite variation was found to be dependent on locus and genotype. The propagation technologies of somatic embryogenesis and rooted cuttings do not cause a loss of genetic diversity in the resulting populations.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.