De nombreuses biomolécules qui constituent les plantes vasculaires ne sont synthétisées que par certains taxons de plantes et ont donc une spécificité chimiotaxonomique. Certaines d'entre elles, tels que les bioterpénoïdes, sont particulièrement résistantes et sont préservées dans les sédiments où elles se transforment en géoterpénoïdes lors de la diagenèse. Ces géoterpénoïdes conservent, partiellement ou totalement, leur spécificité initiale (spécifité paléochimiotaxonomique). Cependant, nos connaissances actuelles en paléochimiotaxonomie botanique, qui permettent d'associer ces biomarqueurs moléculaires à des taxons végétaux, restent encore lacunaires. L'objectif de cette étude est de déterminer la signature moléculaire des familles de conifères fossiles. 68 représentants appartenant aux 7 familles actuelles de conifères ont été artificiellement maturés par pyrolyse en milieu confiné afin de reproduire en laboratoire la transformation des bioterpénoïdes en géopterpénoïdes. Les résultats montrent que les Pinaceae, les Araucariaceae, les Cupressaceae, les Sciadopityaceae, les Podocarpaceae, les Taxodiaceae et les Taxaceae "fossilisés" peuvent se distinguer par la nature et la proportion relative de ces terpénoïdes. De plus, la comparaison des signatures moléculaires ont permis de réaliser des regroupements intergénériques pour chaque famille. Ces regroupements sont comparables avec ceux de la classification phylogénétique. À terme, ces résultats pourront être utilisés dans le cadre d’études paléobotaniques, paléoenvironnementales, environnementales et archéologiques / Many biomolecules that constitute terrestrial vascular plants are only synthesized by a restricted number of plant taxa and have thus a chemotaxonomic specificity. Some of these biomolecules, like the terpenoids, are particularly resistant and can be preserved within sediments where they are transformed into geomolecules during diagenesis. Geoterpenoids keep, partially or totally, their initial specificity (palaeochemotaxonomic specificity). However, our current knowledge in botanical palaeochemotaxonomy, allowing to link these plant biomarkers to plant taxa, remains incomplete. The aim of this study is to determine the molecular signature of fossil conifers. In this objective, 68 species belonging to the 7 extant conifer families were subjected to artificial maturation by confined pyrolysis. This process converts the bioterpenoids included within the plant material into geoterpenoids. The results show that the "fossilized" Pinaceae, Araucariaceae, Cupressaceae, Sciadopityaceae, Podocarpaceae, Taxodiaceae and Taxaceae can distinguished from each other by the nature and the relative proportion of these geoterpenoids. The comparison of these molecular signatures allows to achieve intergeneric groups for each family. These groups are comparable to those of the phylogenetic classification. In the future, these results could be used for palaeobotanical, palaeoenvironmental, environmental and archaeological assessments

Algumas actinobactérias habitantes da rizosfera são produtoras de substâncias capazes de combater micro-organismos patogênicos às plantas, o que as torna potenciais agentes de controle biológico, passíveis de serem utilizadas como princípio ativo de inoculantes de sementes e mudas. O presente trabalho teve como objetivo isolar e avaliar o potencial de isolados de actinobactérias no controle de doenças causadas por fungos nas espécies arbóreas Araucaria angustifolia (Araucária) e Pinus elliottii (Pinus). Além disso, foi iniciado o estudo do processo de elaboração de inoculante a base de actinobactérias antagônicas. Foram isoladas 215 estirpes de actinobactérias do rizoplano da Araucária, das quais 13 apresentaram, em testes in vitro, potencial como antagonistas contra os fungos fitopatogênicos Fusarium oxysporum, Cylindrocladium candelabrum, C. pteridis e Armillaria sp., e apenas os isolados Ac136 e Ac202 apresentaram os maiores valores de inibição nos testes com os quatro patógenos. Na avaliação de produção de algumas substâncias antimicrobianas, apenas celulases, quitinases e sideróforos foram produzidas pelos isolados, sendo este último o mais frequente. Nos testes de interação com organismos foi verificado que, embora os isolados de actinobactéria tenham inibido a germinação de esporos do fungo micorrízico arbuscular (FMA) Gigaspora rosea em teste in vitro, no experimento in vivo, em que foi utilizado o milho como planta hospedeira para inoculação com o FMA e os isolados A43, Ac136 e Ac202, os isolados Ac136 e Ac202 estimularam a colonização das raízes pelo FMA. Estes mesmos isolados também estimularam a germinação de sementes e desenvolvimento inicial de plântulas de Pinus, porém prejudicaram a germinação e desenvolvimento inicial de Araucária. Estes mesmos isolados foram capazes de reduzir a mortalidade de plântulas de Pinus em cerca de 25%, e esta diminuição foi atribuída à inibição de Fusarium sp.. No teste de viabilidade dos isolados em diferentes veículos o isolado que mostrou maior sobrevivência foi o Ac202, mantendo um número de propágulos viáveis correspondente a 5,48 log UFC mL-1, enquanto que o veículo mais apropriado para a elaboração de inoculante com actinobactérias foi a glicerina. A análise molecular mostrou que os isolados mais promissores apresentaram maior similaridade com S. kasugaensis. Dentre todos isolados Ac202 (S. kasugaensis) foi o mais promissor obtido neste trabalho para o uso como agente de biocontrole de doenças causadas por fungos, apresentando forte antagonismo contra os quatro patógenos testados, promovendo a germinação e desenvolvimento inicial de Pinus e aumentando a sobrevivência de plântulas contaminadas com fungos fitopatogênicos. / Some actinobacteria that inhabits the rhizosphere are producers of substances that are capable of combating plant-pathogenic microorganisms, what makes them potential biological control agents, which can be used as the active ingredient of seeds and seedlings inoculants. This study aimed to isolate and evaluate the potential of actinobacteria isolates in controlling diseases caused by fungi in Araucaria angustifolia and Pinus elliottii. In addition, the study initiated the process of elaboration of an actinobacteria-based inoculant. 215 actinobacterial strains were isolated from the Araucarias rhizoplane, and 13 of them showed potential as antagonists against the phytopathogenic fungi Fusarium oxysporum, Cylindrocladium candelabrum, C. pteridis and Armillaria sp. in in vitro tests, and only the Ac136 and Ac202 strains showed the highest inhibition in the tests against the four pathogens. Among the antimicrobial substances tested, only cellulases, chitinases and siderophores were produced, with the latter being the most frequent. In the interaction tests with other organisms it was found that although the actinobacterial strains have inhibited the germination of the arbuscular mycorrhizal fungi (AMF) Gigaspora rosea spores on the in vitro test, the in vivo experiment, with maize as host plant, inoculated with the AMF and A43, Ac136 and Ac202 actinobacterial strains, Ac136 and Ac202 stimulated root colonization by AMF. These strains also stimulated Pinus seed germination and seedling early development, but hindered the germination and early development of Araucaria. In addition, the same strains were able to reduce the mortality of pine seedlings by about 25%, and this decrease was attributed to the inhibition of Fusarium sp.. In the viability test of the strains in different vehicles the strain that showed the greatest shelf-life was Ac202, with 5.48 log CFU mL-1, and the most appropriate vehicle for the actinobacteriabased inoculant development was glycerin. Molecular analysis showed that the most promising isolates showed the greatest similarity with S. kasugaensis. Among all strains Ac202 (S. kasugaensis) was the most promising one for the use as biocontrol agent of fungal diseases, exhibiting a strong antagonism against the four pathogens tested, promoting germination and early development of Pinus and increasing survival of seedlings infected with pathogenic fungi.

This research aimed to determine whether wood microsites ("nurse logs"), which are regeneration sites in Pacific Northwest (PNW) subalpine forests, supported regeneration at timberline-alpine meadow borders. Upward advance of forests and conifer invasion into alpine meadows, which may be occurring in conjunction with climate warming, have gained worldwide attention. Successful alpine meadow seedling regeneration depends on suitable substrate availability, or microsites, for seedling establishment. To better understand factors associated with wood microsite occurrence, mechanisms of wood input were determined and four specific hypotheses were posed to assess: (1) seedling density and seedling survival; (2) growing season length, summer mean growing temperature, and growing degree hours (GDH); (3) active measures of seedling growth; and (4) global wood microsite climate associations. Of four studies, three were conducted in the Cascade Mountains of Washington state along a west - east precipitation gradient and one study, assessed various microsites globally. For Cascades-related research, wood and adjacent soil substrate temperature, moisture, and associated seedling density, survival, stomatal conductance, water potential, and leaf nitrogen were compared by percent transmitted radiation at 4 to 14 study sites. Analysis of variance (ANOVA), t-tests, regressions, and classification and regression trees (CARTs) were used to assess significance of comparisons. Wood microsites, common at 13 of 14 random Cascade sites, had greater seedling densities, greater seedling survival, greater volumetric moisture content (VWC), greater temperature, and greater number of GDH, as compared to adjacent soils. Greater seedling densities were positively associated with VWC (> 12%), conditions most commonly associated with wood substrate presence. For sites having > 25% percent transmitted radiation, positive relationships existed between stomatal conductance and VWC. Globally, high-elevation forests with wood microsites had mean annual precipitation from 86 cm to 320 cm and mean annual temperatures from 1.5°C to 4.7°C. In general, wood microsites facilitated alpine meadow regeneration better than adjacent soils. Management implications included enhanced understanding of factors associated with upward forest advance and wood use for restoration. Globally, wood microsites importance is likely underrepresented. Wood microsites role with warming climate will depend on precipitation pattern, timing, magnitude, and frequency.

The structure and composition of mixed-conifer forest (MCF) in central Oregon has been altered by fire exclusion and logging. The resulting increased density, spatial contagion, and loss of fire resistant trees decrease the resiliency of this ecosystem to fire, drought, and insects. The historical and current composition and structure of MCF are characterized by steep environmental gradients and a complex mixed-severity fire regime. This inherent variation makes it difficult to determine the magnitude of anthropogenic effects and set objectives for restoration and management. As a result, there is a lack of consensus regarding how MCF should be managed and restored across the landscape. My primary research objectives were to: (1) Characterize the current structure and composition of MCF and how these vary with environmental setting; and (2) Characterize establishment and tree growth patterns in MCF in different environmental settings. To address these objectives, I collected field data on structure and composition and increment cores across a range of environmental conditions in MCF of the eastern Cascades and Ochoco Mountains. I used cluster analysis to identify four stand types based on structure and composition in the eastern Cascades study area and four analogous types in the Ochoco Mountains study area. Variation in understory composition and the presence of large diameter shade tolerant species distinguish each type. Stand types occupied distinct environmental settings along a climatic gradient of increasing precipitation and elevation. At relatively dry PIPO sites understories were dominated by ponderosa pine. At wetter PIPO/PSME and PIPO ABGC sites understories were dominated by shade tolerant species, but ponderosa pine was dominant in the overstory. At the coolest and wettest PIPO/PSME/ABGC sites understories were dominated by grand fir and shade tolerant species were common in the overstory. In the eastern Cascades current density of all live trees and snags was 432, 461, 570, 372 trees per hectare (TPH) for the four stand types identified. Stand types in the drier Ochoco Mountains were currently less dense at 279, 304, 212, and 307 TPH. Current MCF densities in both areas are 2-3 times higher than densities estimated for the late 19th and early 20th centuries from other studies in those two areas. Reconstruction of cuts in each stand type indicates that the density of large diameter ponderosa pine has been reduced by approximately 50% in all stand types in both study regions. Age histograms demonstrate that current density and composition of MCF stand types is a product of abrupt increases in tree establishment following fire exclusion in the late 19th century. The number of trees established increased after 1900 in all stand types, but the timing and composition of changes in establishment varied with climate. At dry PIPO sites increases in establishment were delayed until the 1920s and 1930s and were composed of ponderosa pine. At PIPO/PSME and PIPO/ABGC sites with intermediate precipitation, establishment was dominated by ponderosa pine prior to 1900, but after 1900 establishment was dominated by a large pulse of Douglas-fir and grand fir. At the wettest PIPO/PSME/ABGC there was less evidence of changes in structure and composition over time. My results indicate that compared to dry pine and dry-mixed conifer sites, relatively productive moist mixed-conifer sites were characterized by large changes in structure and composition. Such sites could be considered more ecologically altered by lack of fire than drier forest types that had high fire frequencies but slower rates of stand development and less plant community change. Radial growth patterns of cored ponderosa pines differed between the eastern Cascades and Ochoco Mountains. In the eastern Cascades mean growth rates and variance decreased during favorable climatic periods after 1900. This is likely related to increased competition, and provides evidence that current stand density lacks a temporal analog in the 18th and 19th centuries. Sensitivity of growth to climate and harvest suggest competition for water in the denser forest of the eastern Cascades, and indicates thinning will increase the diameter growth rate of large old pines. In the Ochoco Mountains, ponderosa pine tree growth was less responsive to climate prior to fire exclusion in the late 1800s, and growth did not respond to fire events. This suggests competition among trees was historically low in this region. After fire exclusion growth became more responsive to wet and dry climatic cycles, which may indicate that increased density and competition made trees more responsive to climate variability. Patterns of slow and fast growth appeared to differ between study regions and likely differ at the sub-regional scale. Further analysis of the relationship between growth and climate in different environmental settings is needed to distinguish where stand development has been modified by disruption of fire regimes. / Graduation date: 2013

No Brasil, foram introduzidas diversas espécies de Pinus e a espécie P. elliottii Engelm apresenta o comportamento invasor em unidades de conservação de Cerrado, no estado de São Paulo. O objetivo deste estudo foi comparar P. elliottii com outras duas espécies do mesmo gênero, P. caribaea Moret e P. oocarpa Shiede ex Schltdl, através de: viabilidade e germinabilidade das sementes, em laboratório; sobrevivência das plântulas logo após a germinação e acompanhamento de seu crescimento em estufa; germinabilidade em fisionomias campestres; e chuva de sementes dentro de talhões. Para P. elliottii, também foi verificada a distância de dispersão das sementes. As sementes utilizadas nos testes em laboratório foram coletadas em Águas de Santa Bárbara (Estação Ecológica de Santa Bárbara - EEcSB; Floresta de Águas de Santa Bárbara - FASB) e Itirapina (Estação Experimental de Itirapina - EExI). Primeiramente, as sementes foram colocadas em água para separação das sementes cheias das vazias (flutuabilidade). Em seguida, as sementes cheias foram testadas quanto à viabilidade por meio de sal de tetrazólio e quanto à germinabilidade. As sementes germinadas foram acompanhadas até os cotilédones ficarem visíveis e uma parte destas teve o crescimento acompanhado até a 24ª semana. A germinabilidade em fisionomias campestres foi realizada apenas na EEcSB, onde as sementes das três espécies foram semeadas em diferentes graus de umidade do solo. Coletores de sementes foram instalados dentro dos talhões de Pinus spp., tanto na EEcSB-FASB como na EExI, para quantificar a chuva de sementes. A distância de dispersão das sementes de P. elliottii foi avaliada apenas na EEcSB, durante o período de maior dispersão de sementes (março a maio), e teve como classes de distâncias em relação ao talhão: 10, 30, 60, 100, 150 e 250 m. Os resultados dos testes em laboratório mostraram que P. caribaea e P. elliottii apresentam as maiores proporções de sementes cheias (>70%) e P. oocarpa e P. elliottii, as maiores taxas de viabilidade (>90%) e germinabilidade (>90%). Dentre as sementes germinadas das três espécies, mais de 90% desenvolveram-se até o aparecimento dos cotilédones. Quanto ao crescimento, P. caribaea e P. oocarpa apresentaram maior vigor em relação a P. elliottii. Em campo, as três espécies apresentaram, de maneira similar, baixíssima porcentagem de germinação (<1,5% do total semeado), preferencialmente em solos mais úmidos. A chuva de sementes de P. elliottii dentro de talhões foi muito maior (pelo menos o dobro) em comparação com as outras duas espécies. A distância de dispersão das sementes de P. elliottii foi maior nos primeiros 30 m, mas chegou até os 150 m. Portanto, P. caribaea e P. oocarpa apresentaram condições de se tornarem invasores pela viabilidade de suas sementes, vigor de crescimento e germinação em campo, mas o fator determinante para o sucesso na invasão P. elliottii é, provavelmente, a pressão de propágulos, maior do que as outras duas espécies, causada pela sua alta produção de sementes e intenso plantio. / Several pine species of the genus Pinus have been introduced in Brazil, and P. elliottii Engelm is presently considered an invasive species in the Brazilian savanna (Cerrado) in São Paulo State. The aim of this study was to compare P. elliottii with two other Pinus species, P. caribaea Moret and P. oocarpa Shiede ex Schltdl according to: seed viability and germinability, in laboratory; survival of seedlings soon after germination and their growth, in greenhouse; germination at field conditions; and seed rain inside the plantation. The distance of seed distance dispersal was also verified for P. elliottii. The seeds for the laboratory tests were collected in Águas de Santa Bárbara (Santa Barbara Ecological Station - EEcSB; Águas de Santa Bárbara Forest - FASB) and Itirapina (Itirapina Experimental Station - EExI). First, the seeds were placed in water to separate the full from the empty seeds (flutuability). Then full seeds were tested by viability (tetrazolium) and germinability. Germinated seeds were monitored until the cotyledons were visible and some of those were monitored up the 24th week to verify their growth rate. In the EEcSB, seeds of the three species were sown at different levels of soil moisture to observe the germination in the field. In order to quantify the species seed rain seed collectors were installed inside the Pinus spp. stands, in both EEcSB-FASB and EExI. The distance of P. elliottii seed spread was evaluated only at the EEcSB, during the greater period of seed dispersion (March to May), at the distances of 10, 30, 60, 100, 150 and 250 m from the planted areas. The results of laboratory tests showed that P. caribaea and P. elliottii have the highest proportions of full seeds (> 70%) and P. oocarpa and P. elliottii, the highest viability (> 90%) and germination rates (> 90%). Among the germinated seeds of the three species more than 90% developed to seedling stage. Concerning seedling growth, P. caribaea and P. oocarpa showed greater vigor than P. elliottii. In the field, the three species showed similar and very low germination rates (<1.5% of the total sown), preferably in more humid soils. The seed rain of P. elliottii inside the plantation stand was much higher (at least twice) compared to the other two species. The dispersal distance of P. elliottii seeds was higher in the first 30 m, but reached 150 m. The results show that P. caribaea and P. oocarpa are able to become invaders due to their high values of seed viability and germination, and vigor growth, however, the determining factor for the invasive success of P. elliottii is probably its higher propagule pressure, caused by several human mediated introductions, and high production of seeds.

No Brasil, foram introduzidas diversas espécies de Pinus e a espécie P. elliottii Engelm apresenta o comportamento invasor em unidades de conservação de Cerrado, no estado de São Paulo. O objetivo deste estudo foi comparar P. elliottii com outras duas espécies do mesmo gênero, P. caribaea Moret e P. oocarpa Shiede ex Schltdl, através de: viabilidade e germinabilidade das sementes, em laboratório; sobrevivência das plântulas logo após a germinação e acompanhamento de seu crescimento em estufa; germinabilidade em fisionomias campestres; e chuva de sementes dentro de talhões. Para P. elliottii, também foi verificada a distância de dispersão das sementes. As sementes utilizadas nos testes em laboratório foram coletadas em Águas de Santa Bárbara (Estação Ecológica de Santa Bárbara - EEcSB; Floresta de Águas de Santa Bárbara - FASB) e Itirapina (Estação Experimental de Itirapina - EExI). Primeiramente, as sementes foram colocadas em água para separação das sementes cheias das vazias (flutuabilidade). Em seguida, as sementes cheias foram testadas quanto à viabilidade por meio de sal de tetrazólio e quanto à germinabilidade. As sementes germinadas foram acompanhadas até os cotilédones ficarem visíveis e uma parte destas teve o crescimento acompanhado até a 24ª semana. A germinabilidade em fisionomias campestres foi realizada apenas na EEcSB, onde as sementes das três espécies foram semeadas em diferentes graus de umidade do solo. Coletores de sementes foram instalados dentro dos talhões de Pinus spp., tanto na EEcSB-FASB como na EExI, para quantificar a chuva de sementes. A distância de dispersão das sementes de P. elliottii foi avaliada apenas na EEcSB, durante o período de maior dispersão de sementes (março a maio), e teve como classes de distâncias em relação ao talhão: 10, 30, 60, 100, 150 e 250 m. Os resultados dos testes em laboratório mostraram que P. caribaea e P. elliottii apresentam as maiores proporções de sementes cheias (>70%) e P. oocarpa e P. elliottii, as maiores taxas de viabilidade (>90%) e germinabilidade (>90%). Dentre as sementes germinadas das três espécies, mais de 90% desenvolveram-se até o aparecimento dos cotilédones. Quanto ao crescimento, P. caribaea e P. oocarpa apresentaram maior vigor em relação a P. elliottii. Em campo, as três espécies apresentaram, de maneira similar, baixíssima porcentagem de germinação (<1,5% do total semeado), preferencialmente em solos mais úmidos. A chuva de sementes de P. elliottii dentro de talhões foi muito maior (pelo menos o dobro) em comparação com as outras duas espécies. A distância de dispersão das sementes de P. elliottii foi maior nos primeiros 30 m, mas chegou até os 150 m. Portanto, P. caribaea e P. oocarpa apresentaram condições de se tornarem invasores pela viabilidade de suas sementes, vigor de crescimento e germinação em campo, mas o fator determinante para o sucesso na invasão P. elliottii é, provavelmente, a pressão de propágulos, maior do que as outras duas espécies, causada pela sua alta produção de sementes e intenso plantio. / Several pine species of the genus Pinus have been introduced in Brazil, and P. elliottii Engelm is presently considered an invasive species in the Brazilian savanna (Cerrado) in São Paulo State. The aim of this study was to compare P. elliottii with two other Pinus species, P. caribaea Moret and P. oocarpa Shiede ex Schltdl according to: seed viability and germinability, in laboratory; survival of seedlings soon after germination and their growth, in greenhouse; germination at field conditions; and seed rain inside the plantation. The distance of seed distance dispersal was also verified for P. elliottii. The seeds for the laboratory tests were collected in Águas de Santa Bárbara (Santa Barbara Ecological Station - EEcSB; Águas de Santa Bárbara Forest - FASB) and Itirapina (Itirapina Experimental Station - EExI). First, the seeds were placed in water to separate the full from the empty seeds (flutuability). Then full seeds were tested by viability (tetrazolium) and germinability. Germinated seeds were monitored until the cotyledons were visible and some of those were monitored up the 24th week to verify their growth rate. In the EEcSB, seeds of the three species were sown at different levels of soil moisture to observe the germination in the field. In order to quantify the species seed rain seed collectors were installed inside the Pinus spp. stands, in both EEcSB-FASB and EExI. The distance of P. elliottii seed spread was evaluated only at the EEcSB, during the greater period of seed dispersion (March to May), at the distances of 10, 30, 60, 100, 150 and 250 m from the planted areas. The results of laboratory tests showed that P. caribaea and P. elliottii have the highest proportions of full seeds (> 70%) and P. oocarpa and P. elliottii, the highest viability (> 90%) and germination rates (> 90%). Among the germinated seeds of the three species more than 90% developed to seedling stage. Concerning seedling growth, P. caribaea and P. oocarpa showed greater vigor than P. elliottii. In the field, the three species showed similar and very low germination rates (<1.5% of the total sown), preferably in more humid soils. The seed rain of P. elliottii inside the plantation stand was much higher (at least twice) compared to the other two species. The dispersal distance of P. elliottii seeds was higher in the first 30 m, but reached 150 m. The results show that P. caribaea and P. oocarpa are able to become invaders due to their high values of seed viability and germination, and vigor growth, however, the determining factor for the invasive success of P. elliottii is probably its higher propagule pressure, caused by several human mediated introductions, and high production of seeds.

Conifers are important both ecologically and socioeconomically, however, same parts of their biology are not that well researched. This includes genetics and breeding and partly even physiology. Because quantitative genetic analyzes applied in breeding necessitate an analysis of a large number of samples, and conventional methods of analysis are quite time-consuming, certain parameters describing e.g. the activity of photosynthetic electron-transport chain (ETC) are considered for such use. Several methods of the measurement of the activity of photosynthetic ETC exist, but there are some problems with their usage in conifers. I studied this issue from different points of view in three parts of this thesis. 1) I compared the photosynthetic ETC activity in 8 species of conifers using chlorophyll (Chl) fluorescence measurements on intact needles and polarographic measurements in isolated chloroplasts. Each method brought different information. 2) I measured Chl fluorescence parameters, reflectance spectra and pigment content in 536 genetically defined trees of Pinus sylvestris L. Many parameters showed relatively high genetic variability and heritability. I have also determined the suitability of various reflectance indices to estimate pigment and water content of needles. 3) I have optimized the...

L’industrie minière de l’amiante a profondément transformé les paysages du sud du Québec, laissant environ 800 millions de tonnes de résidus miniers sous la forme de haldes près des villes minières telles Thetford Mines et Black Lake. Certains enjeux environnementaux découlant de ces paysages, notamment l’érosion des haldes par le vent et l’eau, ont été atténués avec succès sur certains sites en les recouvrant de technosols composés d’un mélange de matières résiduelles fertilisantes, puis en les ensemençant avec des graminées. Cependant, aucune tentative de boisement n’avait été faite jusqu’à présent, car ces milieux étaient considérés comme trop contraignants pour l’établissement et la croissance des arbres. Dans cette étude, nous avons développé deux plantations expérimentales dans une mine d’amiante en déclassement dans le sud du Québec, sur des stériles et sur des résidus miniers, dans lesquelles a été comparée la performance de huit espèces d’arbres, clones et provenances plantés sur deux types de technosols, tous deux construits à partir d’un mélange de biosolides municipaux et de boues de désencrage aménagés en andains. Les propriétés physiques et chimiques des technosols, comme l’état hydrique et l’activité ionique du sol, ainsi que la survie et la croissance des arbres, ont été évaluées. La nutrition foliaire et l’utilisation de l’eau ont également été étudiées pour trois clones de peupliers hybrides au cours de leur troisième saison de croissance. Les clones de peupliers hybrides avaient une survie significativement plus élevée (87 à 94 %) après trois ans que toutes les espèces de conifères (10 à 56 %) testées. L'espèce résineuse présentant les taux de survie les plus élevés était l'épinette blanche (46 à 56 %). Les conditions sèches lors de la mise en terre peuvent en partie expliquer les taux de mortalité plus élevés des conifères. Les taux de croissance moyens des peupliers hybrides étaient de 45 cm an-1, alors que certains arbres atteignaient plus de 300 cm de hauteur après trois ans. Le phosphore et le potassium étaient les nutriments qui limitaient le plus la croissance. Le clone DN×M-915508 semble être le plus tolérant à la sécheresse. Bien qu'il y ait peu de différences entre les technosols, les résultats suggèrent que l'ajout de sols contaminés de classe B au mélange de matières résiduelles fertilisantes a des avantages pour la survie et la croissance des arbres, probablement en raison du volume de sol plus élevé. Notre étude a démontré une technologie prometteuse pour la remise en état par le boisement des mines d’amiante du sud du Québec. Certains traitements devraient être ajoutés pour limiter la concurrence des plantes au cours des premières années afin d'augmenter la survie et la croissance des arbres, alors qu'un volume limité de technosol et donc une faible disponibilité en humidité et en nutriments pourraient compromettre la croissance à moyen et long terme des arbres. / The asbestos mining industry has deeply transformed the landscapes of southern Quebec, leaving about 800 million tons of tailings and waste rock in large piles near former mining towns such as Thetford Mines and Black Lake. Some of the environmental issues arising from these landscapes (e.g. wind and water erosion) have been successfully addressed at some sites by covering the piles with a mixture of by-products as the technosol and then seeding with grasses. However, no attempt for afforestation had been made thus far because these environments were thought to pose too many constraints on tree establishment and growth. In this study, we developed two experimental plantations at a decommissioned asbestos mine in southern Quebec, on waste rocks and on tailings, as a means to test the performance of eight tree species/clones/provenances planted on two types of technosols, both mainly constructed from the mixing of municipal biosolids and deinking sludge and configured in small windrows. Physical and chemical properties of technosols, including soil water availability and ionic activity, and seedling survival and growth were assessed. Foliar nutrition and water use were also evaluated for three hybrid poplar clones during the third growing season. Hybrid poplar clones had significantly higher survival (87 to 94%) after three years than all conifer species (10 to 56%) tested, although dry conditions at planting could have had adverse effects on conifers. The conifer species exhibiting the highest survival rates was white spruce (46 to 56%). Average growth rates of hybrid poplars were 45 cm y-1, whereas some trees reached over 300 cm in height after three years. Clone DN×M-915508 is believed to be more drought tolerant than the other hybrid poplar clones tested. Phosphorus and potassium were the most growth-limiting nutrients. Although there were few differences between the technosols, results suggest that the addition of Class B contaminated soils to the main mixture of by-products has benefits regarding tree survival and growth, likely because of its larger volume. Our study demonstrated a promising technology for reclamation through afforestation of asbestos mines in southern Quebec. Some treatments should be added to limit plant competition within the first few years as a means to increase survival and growth, whereas limited technosol volume and thus low moisture and nutrient availability could compromise mid- to long-term growth of trees.