Forests are a valuable resource for humans providing a range of products and services such as construction timber, paper and fuel wood, recreation, as well as living quarters for indigenous populations and habitats for many animal and bird species. Most recent international political agreements such as the Kyoto Protocol emphasise the role of forests as a major sink for atmospheric carbon dioxide mitigation. However, forest areas are rapidly decreasing world wide. Thus, it is vital that efficient strategies and tools are developed to encourage sustainable ecosystem management. These tools must be based on known ecological principles (such as tree physiological and soil nutrient cycle processes), capable of supplying fast and accurate temporal and spatial predictions of the effects of management on both timber production and carbon sequestration. This thesis had two main objectives. The first was to investigate the environmental factors affecting growth and carbon sequestration of Scots pine (Pinus sylvestris L.) across Scotland, by developing a knowledge base through a statistical analysis of old and novel field datasets. Furthermore, the process-based ecosystem model 3-PGN was developed, by coupling the existing models 3-PG and ICBM. 3-PGN calibrated using a Bayesian approach based on Monte Carlo Markov Chain simulations and it was validated for plantation stands. Sensitivity and uncertainty analyses provided an understanding of the internal feedbacks of the model. Further simulations gave a detailed eco-physiological interpretation of the environmental factors affecting Scots pine growth and it provided an assessment of carbon sequestration under the scenario of sustainable, normal production and its effects from the environment. Finally, the study investigated the spatial and temporal patterns of timber production and carbon sequestration by using the spatial version of the model and applying advanced spatial analyses techniques. The second objective was to help close the gap between environmental research and forest management, by setting a strategic framework for a process-based tool for sustainable ecosystem management. The thesis demonstrated the procedures for a site classification scheme based on modelling results and a yield table validation procedure, which can provide a way forward in supporting policies for forest management and ensuring their continued existence in the face of the present and future challenges.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 5 uppsatser.

Made available in DSpace on 2016-12-23T13:51:48Z (GMT). No. of bitstreams: 1 Thiago Leite Barbosa - Parte 1.pdf: 10214818 bytes, checksum: 32465fb2672574254ecdfdb0ab63bedc (MD5) Previous issue date: 2013-07-31 / This study aimed to evaluate the effect of site growth on wood quality at two hybrid clones of Eucalyptus grandis x Eucalyptus urophylla with six years old, planted in five regions of the Minas Gerais state. The wood was derived from clonal plantations of the CENIBRA Company, located in the counties of Belo Oriente, Ferros, Santa Barbara, Itabira and Peçanha. For each clone were selected five trees. Of the trunk of the trees were removed discs in five positions equidistant in the tree height and in the DBH position, to measure the percentage of bark, heartwood and sapwood, and to determine the volume of wood and bark. In laboratory conditions, the wood samples were taken in DBH performed analyzes of anatomical, physical and chemical parameters. The results shown that for the two clones, different sites influenced the growth parameters. To the two clones, the specific gravity varied in the longitudinal direction of the trunk in different patterns according to different regions. The behavior of specific gravity of the wood in the radial direction was similar to the methods of immersion and X-ray densitometry, with increase from pith to bark. The clone B had better indexes of uniformity of density in the radial direction when compared to the clone A, being observed that this index had a better relation with the variables of precipitation and water deficit. To the clone B, the region with the highest average precipitation reflected in a lower frequencies of vessels, however, these had greater diameters, besides the presence of wider fibers, with larger lumen diameters and thicker walls. The fiber length of the clone A was more sensitive to the conditions of precipitation and water deficit. In the chemical analysis, the percentage of extractives, lignin and holocellulose differed significantly for the different places where the two clones were planted, allowing observe the regions with higher precipitation were found higher content of lignin and extractives / O presente trabalho teve como objetivo avaliar o efeito do local de crescimento na qualidade da madeira de dois clones híbridos de Eucalyptus grandis x Eucalyptus urophylla, com seis anos de idades, plantados em cinco regiões do estado de Minas Gerais. Os clones estudados foram provenientes de plantios clonais da Empresa Cenibra, localizados nos municípios de Belo Oriente, Ferros, Santa Bárbara, Itabira e Peçanha. Para cada clone foram selecionadas cinco árvores. Do tronco das árvores foram retirados discos em cinco posições equidistantes da altura do fuste e na altura do DAP, para mensurar os teores de casca, cerne e alburno, e determinar os volumes de madeira e de casca. Em condições de laboratório, das amostras de madeira retiradas no DAP, foram realizadas as análises dos parâmetros anatômicos, físicos e químicos. Os resultados indicaram que para os dois clones, os diferentes locais de crescimento influenciaram nos parâmetros dendrométricos. Para os dois clones, a variação da densidade básica da madeira no sentido longitudinal do tronco possuiu diferentes padrões em função das distintas regiões. O comportamento da densidade básica da madeira no sentido radial foi semelhante para os métodos de imersão e de densitometria de raios X, sendo crescente da medula para a casca. O clone B obteve melhores índices de uniformidade da densidade aparente da madeira no sentido radial, quando comparado ao clone A, sendo observado que este índice teve uma melhor relação com as variáveis de precipitação e déficit hídrico. Para o clone B, a região com maior média de precipitação refletiu em menores frequências de vasos, entretanto estes obtiveram maiores diâmetros, além da presença de fibras mais largas, com maiores diâmetros de lume e paredes mais espessas. O comprimento da fibra da madeira do clone A foi mais sensível às condições de precipitação e déficit hídrico. Na análise química, os teores de extrativos, lignina e holocelulose diferiram de forma significativa para os distintos locais onde os dois clones foram plantados, permitindo observar que para região com maior precipitação foram encontrados maiores teores de extrativos e lignina

Thesis (MPhil)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: A thesis undertaken to quantify genotype-by-environment interaction within Eucalyptus grandis clones growing in the eastern portion of South Africa. Thirty one sites were selected to represent the "traditional" E. grandis growing areas of South Africa. Eleven common macro- site variables and twelve common micro- site soil variables were recorded at each site. Twenty seven E. grandis clones and four E. grandis hybrid clones were then evaluated over these 31 sites. An incomplete latin square design was used to evaluate the 31 test clones, and five E. grandis controls were incorporated into the trial design to link the 31 sites. Volume production, stem form, stem defects and survival were assessed at two and five years, as well as the disease infestation of three stem cankers at five years. The analytical methods which were used to evaluate and quantify the GEl portion of the study are the analysis of variance (ANOV A), correlation analysis, and joint regression analysis (IRA) together with the analysis of co-variance (ACOV AR). The growth-site association for volume production, stem form and Endothia disease infestation were investigated using factor analysis (FA), and equations derived for the species and for the individual clones using a stepwise multiple regression approach. GEl, as evaluated through JRA, revealed that an increase in site productivity lead to a positive linear response in productivity on a clonal level, and that there was a diverging or fanning pattern among the regression lines of the clones. This tendency was also observed for both the stem form and the Endothia infestation. Hence, no significant changes in the rankings of the clones were found, and only relevant differences between the clones were found to change significantly. Juvenile-mature genetic correlations for volume production and the stem form showed moderate (rg = 0,66 and rg = 0,70) correlations between the two and the five year assessments. On a species level, rainfall was the main environmental factor responsible for volume production, while latitude was the main influence on stem form and Endothia infestation. On an individual clone basis, some micro-site soil factor interaction within the clones was found for the growth-site response models. Keywords: Eucalyptus grandis, genotype environment interaction, clones, site factors, growth-site response, ANOV A, ACOV AR, GEl, FA, JRA, / AFRIKAANSE OPSOMMING: 'n Studie is ondemeem om die genotipe-omgewingsinteraksie van Eucalyptus grandis klone, wat in die oostelike deel van Suid-Afrika groei, te kwantifiseer. Eenen- dertig groeiplekke is geselekteer om die "tradisionele" E. grandis groeiplekke in Suid-Afrika te verteenwoordig. Elf gemeenskaplike makro-groeiplek veranderlikes en twaalf gemeenskaplike mikro-groeiplek veranderlikes is by elk van die groei areas opgeteken. Sewe-en-twintig E. grandis klone en vier E. grandis basterklone is daama oor hierdie 31 groeiplekke geevalueer. 'n Onvolledige Latynse roosterontwerp is gebruik om die 31 toetsklone te evalueer en vyf kontroles is gebruik om die groeiplekke gemeenskaplik te verbind. Volume produksie, stamvorm, stamdefekte en oorlewing is op twee- en vyfjarige ouderdomme geevalueer terwyl besmetting met drie stamkankers op vyf jaar beoordeel is. Die analitiese metodes wat gebruik was om genotipeomgewingsinteraksie te evalueer en te kwantifiseer is die variansie analise (ANOYA), korrelasie analise, en gesamentlike regressie analise (JRA) tesame met ko-variansie analise (ACOY AR). Die groeiplek assosiasie vir volume produksie, stamvorm en Endothia besmetting is ondersoek deur gebruik te maak van faktor analise (FA), en vergelykings is verkry vir die spesies en individuele klone deur gebruik van 'n stapsgewyse meervoudige regressie benadering. Genotipe-omgewingsinteraksie, soos geevalueer deur JRA, wys dat 'n toename in groeiplek produktiwiteit lei tot 'n positiewe lineere reaksie in produktiwiteit op klonale vlak en dat daar 'n divergerende patroon tussen die regressielyne van die klone is. Hierdie tendens is ook vir beide die stamvorm en Endothia besmetting waargeneem. Gevolglik is nie-beduidende veranderings in die rangorde van die klone gevind en slegs reletiewe verskille tussen klone is gevind. Onvolwasse-volwasse genetiese korrelasies vir volume produksie en stamvorm toon matige korrelasies (rg =0.66 en rg =0.70) tussen die twee- en vyfjaar metings. Op 'n spesiesvlak was reenval die oorheersende omgewingsfaktor verantwoordelik vir volume produksie terwyl die breedtegraad ligging stamvorm en Endothia besmetting bemvloed het. Op individuele kloonvlak het sommige mikro-groeiplek interaksie binne klone bygedra tot die groei en groeiplek reaksie modelle. Sleutelwoorde: Eucalyptus grandis, Genotipe-omgewingsinteraksie, klone, groeiplek faktore, groeiplek reaksie, ANOY A, ACOY AR, FA, JRA