Thesis (Ph. D.)--Rijksuniversiteit te Utrecht, 1988. / Includes bibliographical references (p. 233-242) and index.

Made available in DSpace on 2014-08-20T13:32:45Z (GMT). No. of bitstreams: 1 tese_daiane_de_pinho_benemann.pdf: 2735667 bytes, checksum: 56ce2e3c78770a1745bd363c525c5392 (MD5) Previous issue date: 2012-05-24 / Gerbera is one of the most important plants in the global ornamental market. Due to fierce competition in this market, obtaining different genotypes is necessary. Therefore, information on the genetic variability of this species may help breeding programs in order to select new promising genotypes. This study aimed to develop EST-SSR markers for gerbera, and to check the genetic variability among accessions by multivariate analysis using morphological (qualitative and quantitative), and molecular markers. Also to analyze the correlation between morphological and molecular markers to elucidate the genetic variability of Gerbera spp.. As a result, 17 EST-SSR markers were developed for use in studies of molecular characterization. These were highly polymorphic and allowed the differentiate of all gerbera accessions. The analysis of morphological (quantitative and qualitative) characters, by means of multivariate analysis and principal components enabled the delection of a wide genetic variability among accessions of gerbera. The correlation analysis between morphological characters show that there is some influence on other characters. The analysis of molecular and morphological data, using the sum of the dissimilarity matrices, it was possible to obtain a better grouping of the accessions studied. The results of this study may assist gerbera breeding programs in the selection of parental genotypes for controlled crossings. / A gérbera é uma das plantas mais importantes no mercado mundial de ornamentais. Dada a grande concorrência nesse mercado, a obtenção de genótipos diferenciados é uma necessidade constante, sendo assim, informações sobre a variabilidade genética desta espécie podem auxiliar programas de melhoramento, visando a seleção de novos genótipos promissores. No presente estudo buscou-se desenvolver marcadores EST-SSR para gérbera, com os objetivos de caracterizar molecularmente esta espécie, verificar a variabilidade genética entre acessos, por meio da análise multivariada utilizando caracteres morfológicos (qualitativos e quantitativos), analisar a correlação entre os caracteres morfológicos e moleculares para uma melhor elucidação da variabilidade genética de Gerbera spp.. Como resultados, 17 marcadores EST-SSRs foram desenvolvidos para uso em estudos de caracterização molecular. Estes foram altamente polimórficos e capazes de diferenciar todos os acessos de gérbera. A análise dos caracteres morfológicos (quantitativos e qualitativos), por meio de análise multivariada e componentes principais, possibilitou verificar a existência de ampla variabilidade genética entre os acessos de gérbera. Através da correlação entre os caracteres morfológicos, constatou-se que existe influência de alguns caracteres sobre outros. Na análise conjunta dos dados moleculares e morfológicos, por meio da soma das matrizes de dissimilaridade, foi possível obter um melhor agrupamento entre os acessos estudados. Os resultados obtidos neste estudo poderão auxiliar programas de melhoramento genético de gérbera na seleção de progênies promissoras para cruzamentos controlados.

Doctorat en sciences sociales, politiques et économiques / info:eu-repo/semantics/nonPublished

Orientadores: Anete Pereira de Souza, Antonio Augusto Franco Garcia / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-08T00:10:19Z (GMT). No. of bitstreams: 1 Oliveira_KarineMiranda_D.pdf: 6932327 bytes, checksum: 92b9fb104f8543695a1c804fd65bf912 (MD5) Previous issue date: 2006 / Resumo: A cana-de-açúcar (Saccharum spp.) está entre as espécies de maior importância econômica no mundo, constituindo uma das principais fontes de produção de açúcar e álcool. Apesar do Brasil ocupar posição de destaque, como o maior produtor mundial, os níveis de produtividade são considerados baixos. Os programas de melhoramento para obtenção de novas variedades de cana-de-açúcar, mais produtivas e resistentes a pragas e doenças, podem ser acelerados com o desenvolvimento de marcadores genéticos, PCR específicos, fortemente ligados a genes que controlam as características de interesse. A utilização de marcadores em estudos de mapeamento genético e de QTL¿s (Quantitative Trait Loci) tem proporcionado um importante progresso no conhecimento da estrutura genômica e na genética da cana-de-açúcar. Sabe-se que os ESTs (Expressed Sequence Tags) apresentam grande potencial para serem utilizados com tais finalidades. O projeto de seqüenciamento de ESTs (SUCEST), do programa Genoma da FAPESP, identificou cerca de 43 mil clusters que representam os genes de cana-de-açúcar, potenciais para serem utilizados no desenvolvimento de marcadores genéticos. Neste contexto, o presente trabalho teve como objetivo desenvolver e mapear marcadores EST-SSRs em uma progênie derivada do cruzamento entre duas variedades pré-comerciais de cana-de-açúcar, complementando os programas de mapeamento genético desta população. Uma busca no banco de dados do SUCEST resultou na identificação de marcadores microssatélites ou SSRs (Single sequence repeats) em 2005 clusters. Trezentos e setenta e dois locos EST-SSRs foram desenvolvidos e analisados e, destes, 149 foram selecionados para estudo de mapeamento genético. Um total de 2303 marcadores polimórficos (SSRs, EST-SSRs, RFLPs, EST-RFLPs e AFLPs) foi identificado nos 100 indivíduos da progênie F1, dos quais 1669 (72%) eram marcadores em dose simples (1:1 e 3:1), segregantes na população. As análises de mapeamento foram baseadas na metodologia de identificação de marcadores em dosagem única no genoma, com o auxílio dos programas JoinMap (versão 3.0) e OneMap. Para a formação dos grupos de co-segregação (GCs) utilizou-se LOD 5 e fração de recombinação de 0.35. A função de mapeamento de Kosambi foi adotada para conversão das freqüências de recombinação em distâncias de mapa em centiMorgans (cM). Dos 1669 marcadores segregantes, 664 (40%) foram distribuídos em 192GCs, gerando um mapa com 6261.1 cM de comprimento. Os 192 GCs foram agrupados em 14 prováveis grupos de homologia. Cento e treze dos 149 EST-SSRs avaliados foram mapeados e apresentaram homologia a genes conhecidos de outras espécies. A adição dos marcadores provenientes de seqüências expressas, aumentou a cobertura e densidade do mapa prévio desta população, possibilitando também a construção do primeiro mapa funcional de cana-de-açúcar. Os EST-SSRs desenvolvidos têm potencial de utilização na detecção de QTL¿s associados a características de importância econômica para a cultura da cana-de-açúcar / Abstract: Sugarcane (Saccharum spp.) is one of the most important cash crops, highly contributing towards the production of raw sugar and bioethanol produced worldwide. Even though Brazil is the major producer, sugar yield is considered low. Breeding programs for the attainment of new improved sugarcane varieties, which are more productive and more resistant to plagues and illnesses, could be sped up with the development of genetic markers that are PCR-specific and strongly linked to genes that control the desired agronomic traits. The use of genetic markers in genetic mapping and QTL (Quantitative Trait Loci) studies has allowed important progress in the knowledge of the genomic structure and genetics of sugarcane. It is a known fact that the ESTs (Expressed Sequence Tags) have great potential to be used with such purposes. The Sugarcane Expressed Sequence Tag Project (SUCEST) has identified about 43000 clusters that represent the sugarcane genes with a potential to be used in the development of genetic markers. In this context, the objective of the present work was to develop and map EST-SSR markers in a progeny obtained by the cross between two pre-commercial sugarcane varieties, complementing the genetic mapping programs of this population. A search in the SUCEST database resulted on the identification of the microssatellites or SSR (Single sequence repeats) markers in 2005 clusters. Thus, three hundred and seventy two EST-SSR loci had been developed and analyzed and, out of these, 149 were selected for mapping analyses. A total of 2303 polymorphic markers (SSRs, EST-SSRs, RFLPs, EST-RFLPs and AFLPs) were identified among the 100 F1 individuals, of which 1669 (72.5%) were single dose (SD ¿ segregated 1:1 and 3:1) markers. Map analyses were carried out using JoinMap (version 3.0) and OneMap algorithm, based on a single-dose marker approach. The linkage relationships of simplex markers were determined at a LOD score threshold of 5 and a recombination fraction threshold of 0.35 and map distances were derived from the recombination fraction using the Kosambi function. Out of these 1669 SD markers, 664 (40%) were scattered onto 192 co-segregation groups (CGs) with a total estimated map length of 6261.1 cM. Using both genomic and EST-derived SSR and RFLP, 120 of the 192 CGs were formed into fourteen putative homology groups (HGs). One hundred and thirteen of the 149 EST-SSRs evaluated were mapped and presented homology to previously studied genes of other species. The addition of the EST-derived markers increased the coverage and density of the previous map of this population, which also enabled the construction of the first functional linkage sugarcane map. The EST-SSRs developed have the potential to be used in the detection of QTLs associated to important economic traits for sugarcane culture / Doutorado / Genetica Vegetal e Melhoramento / Doutor em Genetica e Biologia Molecular

Un des objectifs ultimes en écologie évolutive est de comprendre les mécanismes responsables du maintien de la biodiversité en milieu naturel. La biodiversité englobe la diversité des écosystèmes, des espèces, des populations et aussi la diversité génétique associée à une espèce donnée. Même à l’intérieur d’une espèce, on peut observer une grande diversité de phénotypes et de génotypes résultant de l’interaction entre la sélection naturelle, le flux génique, la dérive génétique et les mutations. L’objectif central de cette thèse est d’évaluer la variabilité génétique et le potentiel d’adaptation chez le saumon atlantique, Salmo salar, en milieu naturel. L’analyse de 51 rivières à saumon aux marqueurs microsatellites révèle une structure de populations hiérarchique et suggère l’existence de sept groupes régionaux au Québec, Labrador et Nouveau-Brunswick, Canada. Les analyses en génétique du paysage suggèrent l’influence prédominante du flux génique et de l’adaptation thermique dans l’établissement de la différentiation génétique. Des évidences indirectes suggèrent également que les immigrants provenant d’un autre groupe régional ont un succès reproducteur moindre dans leur nouveau milieu que les résidents. Différents niveaux de structuration génétique ont aussi été observés à l’intérieur même de certaines rivières, remettant en cause la gestion par rivière chez cette espèce. La variabilité à grande échelle d’un gène d’immunocompétence, le gène du Complexe Majeur d’Histocompatibilité (CMH) classe IIβ, démontre que la diversité génétique au CMH augmente avec la température et la diversité bactérienne présente en rivière, contrairement au patron observé aux microsatellites. L’augmentation de la diversité au CMH avec la température est plus prononcée aux sites de liaison aux pathogènes qu’aux autres sites moléculaires, suggérant une influence plausible de la diversité des pathogènes, elle-même dépendante de la température, sur l’adaptation locale du saumon atlantique. Finalement, l’étude des infections pathogéniques chez les saumons juvéniles révèle un taux d’infection accru en début de saison estivale dans les rivières de la rive sud du Saint-Laurent, concordant avec les pressions de sélection du milieu. Un parasite prédominant et possiblement récemment introduit, un myxozoaire du genre Myxobolus, a été découvert chez les jeunes saumons et deux allèles CMH ont été identifiés comme étant associés à la résistance et à la susceptibilité face à cette infection, suggérant l’importance de la variation génétique présente au CMH pour faire face aux pathogènes dans un contexte de changement environnemental. Cette thèse ajoute à notre compréhension sur les mécanismes qui maintiennent la variabilité génétique et influencent l’adaptation locale chez le saumon atlantique sauvage grâce à des analyses novatrices en génétique du paysage, en structure de population et sur les patrons spatio-temporels d’infection en milieu naturel. / One of the central endeavors in evolutionary ecology is to understand the mechanisms responsible for natural biodiversity. Biodiversity is defined as the combined diversity of ecosystems, species, populations and the genetic diversity within a given species. Even within a species, a wide diversity of phenotypes and genotypes is often observed, resulting from the interaction between natural selection, gene flow, genetic drift and mutations. The central objective of this thesis was to assess the genetic variability and evaluate the potential for local adaptation in wild Atlantic salmon, Salmo salar. Analyses of neutral molecular markers in 51 salmon rivers revealed a hierarchical genetic structure and suggested the existence of seven regional groups in Québec, Labrador and New-Brunswick, Canada. Landscape genetic analyses suggested a predominant influence of gene flow and thermal regime adaptation in maintaining genetic differentiation. Indirect evidence also suggested that immigrants from a different regional group were less successful in establishing in the new environment compared to residents. Different extents of genetic structure were also found within some river systems, questioning the river-based management approach in Atlantic salmon. Large scale genetic variability at an immuno-competence gene, the Major Histocompatibility Complex (MHC) class IIβ gene, revealed that genetic diversity increased with increasing temperature and bacterial diversity in rivers contrary to patterns with neutral microsatelite markers. This increase in MHC diversity with temperature was more pronounced at the peptide-binding region involved in pathogen binding than at other molecular sites. These results agree with the hypothesized influence of temperature-associated pathogen diversity on local adaptation in Atlantic salmon. Finally, pathogen infections in juvenile salmon were found to be more frequent at the beginning of the summer in southern rather than northern rivers, in concordance with pathogen selection pressure in the wild. A predominant and possibly introduced pathogen, a myxozoa of the genus Myxobolus, was identified in juvenile salmon and two MHC alleles were found to be associated with resistance and susceptibility to that infection, suggesting the importance of MHC standing genetic variation for facing pathogens in a changing environment. This thesis contributes to our understanding on mechanisms maintaining genetic variability and influencing local adaptation in wild Atlantic salmon through analyses in landscape genetics, genetic population structure and patterns of spatio-temporal infectivity in nature.

Au Canada, il est estimé que 14 à 26 % des enfants de la population générale ont un parent atteint d’un trouble de santé mentale majeur, ce qui représente environ 12 000 enfants dans la région de Québec. Malgré les nombreuses recherches dans le domaine, les effets de vivre avec un parent atteint d’un tel trouble demeurent encore méconnus. En ce sens, la présente recherche a pour but d’explorer le vécu d’adultes ayant grandi avec un parent atteint d’un trouble de santé mentale majeur. Plus spécifiquement, les questions de recherche sont les suivantes : 1) Quels événements et points tournants ont influencé le parcours de vie de ces adultes? 2) Comment les relations familiales et sociales évoluent-elles pour eux? 3) Quelles distinctions dans leur vécu permettent de comprendre le fonctionnement global « allant bien » par rapport à celui « allant moins bien »? Pour ce faire, des entrevues semi-structurées auprès de douze participants, dont une moitié a été jugée comme « allant moins bien » et l’autre moitié comme « allant bien » par des informateurs clés, ont été réalisées. Par l’intermédiaire de la théorie du parcours de vie, une analyse par thématique a été effectuée. Cette dernière fait ressortir la prise de conscience du trouble mental du parent comme point tournant dans le parcours de vie des participants ainsi que les effets positifs et négatifs de leurs différentes relations familiales et sociales. Finalement, peu d’éléments différencient le groupe jugé comme « allant bien » de celui « allant moins bien ». / In Canada, it is estimated that 14 to 26 % of children within the general population have a parent with a mental illness, which represents approximately 12 000 children in Quebec region. Despite numerous studies on this subject, the effects of living with a parent with mental illness are not well known. The aim of this research is to explore the experience of adults who grew up with one mentally ill parent. More specifically, the research questions are: 1) What are the events and turning points that have influenced the life course of those adults? 2) How do the familial and social relationships evolved? 3) What are the distinctions between the group considered as “well-being” and the other considered as “not so well”? To do so, semi-structured interviews have been conducted among twelve participants, half of which being considered as “well-being” and the other half as “not so well”. According to the life course theory, thematic analysis was applied. This helped identifying the awareness of the parent’s illness as a turning point in the life course of the participants and the positive and negative effects of relationships with family members and other social relationships. Finally, results show that the elements studied do not differentiate the group considered “going well” from the one “not so well” in a life course perspective.

Cette étude portant sur les glissements de terrain dans la vallée de la rivière Malbaie, en particulier sur le Grand glissement de Clermont, est basée sur la géomorphologie, la stratigraphie et la sédimentologie des dépôts meubles. L’analyse multidate de six séries de photographies aériennes a permis de répertorier les glissements ayant affecté la section aval de la vallée. D’après les données, il s’avère que les glissements à grande superficie sont antérieurs à 1950. L’étude de coupes stratigraphiques et de piézocônes a mis en évidence la présence de dépôts de glissements insérés entre des unités sédimentaires intactes. Les dates radiocarbones du matériel organique surmonté ou enfoui dans des sédiments déplacés et resédimentés démontrent que le glissement est survenu entre 1520 et 1580 AD. Cet évènement a probablement affecté divers endroits de la vallée; l’étude d’autres coupes situées en aval a fourni des résultats similaires, soit entre 1490 et 1600 AD.

Cette thèse montre la façon dont les paysans-autochtones de Chillimocco (dans les Andes péruviennes) constituent leur rapport à la terre à travers l’activité agricole. Celle-ci est envisagée de façon à ne plus la considérer comme un ensemble de « techniques » qu’on impose sur la « nature » pour la soumettre, mais comme un continu qui associe du technique et du rituel et qui, ce faisant, établit un rapport symétrique entre hommes et terres. Nous faisons une description approfondie de la façon dont l’agriculture est menée dans ce village andin, afin de dégager les principes qu’elle met en place. La démarche analytique que nous suivons est double. Un premier niveau d’analyse est constitué par l’examen des catégories locales que dégage l’activité agricole. Elles-mêmes constituent un premier indice du rapport à la terre à Chillimocco, mais pour s’interroger à propos de la « rationalité » de ce rapport, on ne peut pas opérer une interpolation automatique. Un deuxième niveau d’analyse est alors opéré à l’aide d’une notion de rationalité révisée afin de la rendre abordable par l’anthropologie. Pour ce faire, on se sert de certains éléments de l’anthropologie symétrique qui nous permettent de remanier ladite notion et de l’investir des sens locaux dégagés par le premier niveau d’analyse. Les notions locales nous aident à envisager une rationalité sociale plus enracinée, mais aussi elles brisent nos catégories de départ et nous conduisent progressivement vers des notions plus aptes à saisir la différence ontologique que posent les Chillimoccokuna. La catégorie de « rituel », chère à l’anthropologie, est ainsi remise en question. Dans un premier moment, on met en œuvre un traitement du rituel cohérent avec la façon dont Edmund Leach (dépassant le rituel comme type d’action) l’envisageait comme un trait de l’action. Mais la considération de la condition ontologique des acteurs impliqués fait que cette thèse finisse par remettre en question la distinction entre traits rituels et traits techniques elle-même. Enfin, par notre approche qui va au-delà de la symétrie généralisée de Bruno Latour, par une préoccupation analytique autoréflexive fondée sur l’expérience, et par la prise en compte de formes d’existence multiples, ce travail établit une démarche que nous appelons d’ontographie. / This doctoral thesis shows how native peasants from Chillimocco (in the Peruvian Andes) establish a relationship with the land through agriculture. The latter is viewed not as a set of “techniques” imposed on “nature” to subject it, but as a continuum that combines technique and ritual and, in doing so, establishes a symmetrical relationship between human beings and lands. We describe in-depth how agriculture is carried out in this Andean village in order to bring out the principles it sets up. Our analytical work is twofold. A first level of analysis is constituted by the examination of local categories brought out by agricultural activities. These categories constitute a first marker of the relationship with the lands at Chillimocco, but to interrogate the “rationality” of this relationship one cannot undertake an automatic interpolation. Then a second level of analysis is undertaken with the help of a notion of “rationality” that has been revised in order to make it accessible to anthropology. To achieve this, we use some elements of the Symmetrical Anthropology that allow us to rework such notion and to endow it with the local meanings undertaken in the first level of analysis. The local notions help us not only to envision a more grounded social rationality, but also to unsettle our categories of departure; progressively leading us to more adapted notions to grasp the ontological difference revealed by the Chillimocco. Thus, the pertinence of “ritual, ” a category of great concern in the anthropological tradition is put into question. In a first moment, we treat ritual in agreement with how Edmund Leach visualized it, i.e. like a trait of all action (going beyond ritual as a type of action). However, the ontological condition of the actors involved, make that this dissertation also questions the distinction between ritual traits and technical traits. Finally, our approach that goes beyond Bruno Latour’s generalized symmetry, our self-reflexive analytical work based on experience, and our concern with multiple forms of existence, make of this work more an “ontographic” effort than a classical ethnography.

Made available in DSpace on 2014-07-29T15:27:26Z (GMT). No. of bitstreams: 1 Dissertacao Regys Rodrigues da Mota.pdf: 501416 bytes, checksum: 0e81f8c14b69ee88f9f30d8e22bd1a3f (MD5) Previous issue date: 2011-08-08 / The goal of this research is to analyze the process of democratization of political elites observing changes and continuities in the profile of the parliamentarians in the composition of the Legislative Assembly of Goiás during the period 1982 to 2010. / A dissertação tem como objetivo analisar a elite política goiana observando mudanças e continuidades no perfil dos parlamentares presentes na composição da Assembléia Legislativa de Goiás durante o período de 1982 a 2010. Para tanto, o estudo foi desenvolvido por meio de pesquisa bibliográfica para aprofundamento teórico a respeito do tema Teoria das Elites e mediante pesquisa documental com a finalidade de analisar dados referentes ao perfil socioeconômico dos deputados da Assembléia Legislativa de Goiás.

Les émissions anthropogéniques de dioxyde de carbone ont changé le climat de la Terre. Les forêts boréales contiennent de vastes quantités de carbone (C) et peuvent donc jouer un rôle crucial dans le cycle du C global. Les pessières noires dominent la forêt boréale nord-américaine, il est donc nécessaire de comprendre leurs réponses à la variabilité du climat et aux perturbations écologiques telle la récolte forestière afin d’identifier les facteurs influençant les échanges de C entre la biosphère terrestre et l’atmosphère. Le premier chapitre de recherche (Chap. 3) présente une comparaison des échanges de C de trois pessières noires matures de différentes régions du Canada. Cette étude a montré que le sol plus chaud sous un couvert de neige plus épais en hiver et de faibles niveaux de lumière en juin au site de l’est du Canada, des conditions communes dans cette région, ont réduit la séquestration de C relativement aux sites du Canada central. Une paramétrisation générale à une échelle de temps mensuelle a suffit à caractériser la réponse des pessières noires matures aux conditions environnementales. Dans le deuxième chapitre de recherche (Chap. 4), le bilan de C et la réponse des échanges de C aux conditions environnementales de pessières noires mature et récemment récolté de l’est du Canada ont été quantifiés. Le bilan de C de ces pessières noires était davantage affecté par leur stade de développement que les variations interannuelles du climat. La réponse des échanges de C aux facteurs environnementaux a montré une plus forte variabilité entre et à l’intérieur des années au site récolté due à la structure dynamique de la végétation. Le troisième chapitre de recherche (Chap. 5) concerne les échanges de C du parterre forestier d’une pessière noire mature de l’est du Canada mesurés sur différents microsites. La respiration du sol et la photosynthèse du parterre forestier ont respectivement contribuées à 76-88% et 16-17% de la respiration et de la photosynthèse totales de l’écosystème. Les différences observées de réponse de la respiration du sol aux facteurs environnementaux suggèrent que le type de microsite peut refléter la variabilité spatiale de la respiration du sol. Ces trois études procurent de l’information utile pour paramétrer et modéliser la réponse de la forêt boréale aux variations du climat et aux perturbations écologiques. / Carbon dioxide emissions from human activities are changing the Earth’s climate. The boreal forest contains enormous carbon (C) stocks and hence it plays a critical role in the global C cycle. Black spruce ecosystems are the dominant cover type in the North American boreal forest, thus it is necessary to understand their response to both climate variability and to ecological disturbances such as forest harvest so as to identify the factors influencing C exchange between the biosphere and the atmosphere. The first research chapter (Chap. 3) of this thesis presents a comparison of C exchange for three old black spruce ecosystems located in different regions of Canada. This study showed that warmer soil under deeper snowpack in winter and low light levels in June at the eastern Canada site, which are common conditions in that region, reduced C sequestration relative to that of similar ecosystems in central Canada. Furthermore, a general parameterization at a monthly time resolution was sufficient for characterizing the physiological response of all three black spruce ecosystems to environmental conditions. In the second research chapter (Chap. 4), the C balance and the response of C exchange to environmental conditions of a mature and a recently harvested black spruce site in eastern Canada were quantified. The C balance of these black spruce ecosystems was more affected by their respective developmental stage than by inter-annual climate variability. The response of C exchange to environmental factors showed a greater between- and within-year variability at the harvested site due to the dynamic structure of the vegetation. The third research chapter (Chap. 5) examined forest floor C exchange for a mature black spruce site in eastern Canada measured on different microsites. Soil respiration and forest floor photosynthesis accounted for 76-88% and 16-17% of total ecosystem respiration photosynthesis, respectively. The observed differences of the response of soil respiration to environmental factors suggest that microsite can reflect the spatial variability of soil respiration. All three of these studies provide valuable information for parameterizing and modeling the response of boreal forests to climate variability and to ecological disturbance.