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The objective of this thesis was to understand the spatial patterns and processes responsible for canopy and understorey spider (Arachnida: Araneae) diversity at multiple spatial scales in north-temperate hardwood forests. I sampled tree trunks (sticky traps) and foliage (beating) of sugar maple and American beech tree canopies and their understorey saplings in old growth forests near Montreal, Quebec. Results show the composition of canopy and understorey assemblages differed significantly, and so did sugar maple and American beech canopy assemblages. Each stratum was also dominated by different species. The rank-abundance distribution of species from each habitat wsa also verticaly stratified because it fit different distribution models. Different factors likely structure assemblages in both habitats, particularly since the canopy is a less stable environment. Spiders from canopy and understorey foliage were tested in a laboratory for their propensity to balloon. General linear models indicated that small sized web-building spiders of the RTA and Orbicularia clades have the highest propensity to balloon. Small bodied species initiated ballooning regardless of the habitat they were collected in or their developmental stage. My results support the mixed evolutionarily stable strategy theory and indicate the absence of risk-spreading in the dispersal strategy of canopy spiders. My last chapter focused on dispersal capacity and diversity patterns of spiders at multiple spatial scales. Analyses of the species diversity of limited and high dispersal capacity species subsets through nested-multivariate ANOVA, additive diversity partitioning, and species-abundance distribution curves all point towards species-sorting processes as the main driver of local community spider diversity at the tree and stand spatial scales. Mass-effects and patch-dynamic processes drive site and regional scale diversity patterns. This thesis demonstrates that spiders provide good models to test many biological hypotheses. The research chapters of this thesis test hypotheses on the vertical stratification of forest spider diversity, the evolution of local dispersal adaptations, and the importance of dispersal capacity on species diversity patterns through a metacommunity framework.

The dynamics in Fagus-Acer forest have been frequently investigated, a particular interest being the replacement patterns and coexistence of the two dominant species, Fagus grandifolia Ehrh. and Acer saccharum Marsh. This thesis examines whether the community pattern and dynamics in a Fagus-Acer forest at Mont. St. Hilaire, Quebec, are consistent with predictions made by the disturbance hypothesis. This conceptual model explains the mechanisms underlying the coexistence and replacement patterns of the two dominant species. While the hypothesis suggests disturbance frequency and interspecific differences in growth under variable light conditions to be the key factors that determine the dynamics in Fagus-Acer forests, I demonstrate that edaphic factors and regeneration of Fagus by root sprouts can also play a significant role. Based on the findings, I propose an alternative model for the coexistence and replacement patterns in Fagus-Acer forest to better account for the influence of edaphic factors and of Fagus root sprouts.

This thesis used novel methodologies in dendrochemistry to observe past nutrient and Al change in relation to incremental stem xylem growth to predict current and future forest health. The methods included (1) sequential digestion of wood tissue to remove the elemental fraction that is mobile across tree rings leaving the structurally intrinsic, residual (or less mobile) ion fraction for analysis and (2) transformation of elemental concentrations into multivariate ratios (compositional nutrient diagnosis (CND)) over a time series. Sampling of trees represented a gradient in acidity resilience using three regions of southern Quebec (St. Lawrence Lowlands; Lower Laurentians; and Appalachian Highlands) and three species (red maple ( Acer rubrum L.); sugar maple (Acer sacharum Marsh.); and American beech (Fagus grandifolia Ehrh.). The elemental residual fraction had differences from the mobile fraction over time for Ca, Mg and Mn, but not for K or Al. The base rich Saint-Lawrence region had the highest and slightly increasing incremental stem xylem Al of the regions yet had stable or increasing growth. By contrast the acid sensitive Appalachian region had the greatest increase in Al accompanied by a decrease in growth beyond 1970. The Appalachians also had the highest Mn, which had an adverse effect on growth of sugar maple. The acid-resilient species American beech had stable or decreasing Al while having stable or increasing growth in contrast to the less resilient sugar and red maple. The nutrient poor Laurentian region had a persistent deficiency of K over time but no relationships with Al. Aluminium had a general negative correlation with the other canons. Although Mn had the highest levels in red maple for each region, it appears to be limiting growth. The changes in wood chemistry and growth over time appear to be driven by the resilience of the region or species to increasing acidic load in the ecosystems.

The purposes of this creative project were (1) to develop a stone conservation plan for some of the markers in the "Old Part" of Beech Grove Cemetery, (2) to bring attention to the plight of a sampling of the cemetery stone markers in the "Old Part," and (3) to provide a written and photographic database for those individuals who are concerned with the preservation/conservation of Beech Grove Cemetery, in the hopes that a conservation plan can be implemented throughout the cemetery.Results revealed that a vast majority of Beech Grove's markers are deteriorating due to several natural factors such as weathering and erosion, as well as to neglect and vandalism. I have included, in this project, 195 stone inventory forms with a correlating map and photograph of those stones surveyed. The results also confirmed my theory that little conservation has taken place in the cemetery. Some conservation efforts that have been applied to the stone markers have further damaged them due to inappropriate methods. / Department of Architecture

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No description available.

Tüpfel ermöglichen den interzellularen Stoffaustausch im Holzkörper. Im Zuge der Prozessgestaltung in den Bereichen Holzschutz und Zellstoffherstellung sind genauere Kenntnisse über ihren Aufbau von grundlegender Bedeutung. Das anatomische Wissen ermöglicht eine verbesserte Einschätzung der Tränkbarkeit sowie allgemein über die Eindringwege von Flüssigkeiten im Holz. Die Arbeit fasst den aktuellen Wissensstand des Baus der Tüpfel im Laubholz zusammen. Dabei stehen die in Deutschland wichtigsten Laubbaumarten, namentlich die Rot-Buche (Fagus silvatica L.) und Stiel- sowie Traubeneiche (Quercus robur L. und Quercus petraea Liebl.), im Fokus der Untersuchung. Zunächst wird der allgemeine Aufbau der Tüpfel beschrieben und besonders neuere Erkenntnisse mit aufgegriffen. Im Anschluss wird der Wissensstand zur Tüpfelbau der Rot-Buche sowie der Stiel- wie Trauben-Eiche zusammengefasst dargestellt.

A sustainable approach to restoration of the post-mining landscape involves creating conditions where a viable growth medium can be established with the minimal amount of fertiliser inputs over a period of time. Ideally, this growth medium should comprise a combination of minerals, organic matter, and biological components with have the capacity to retain and release nutrients over time. When combined with a re-vegetation scheme appropriate to the biogeographic area, a self-sustaining ecosystem can be established. Regulatory requirements for mine restoration typically require the use of topsoil, which is often in limited supply. However, overburden is commonly present in vast quantities and has the potential to be used as a restoration substrate with appropriate amendments. There are significant gaps in our understanding of factors relating to the use and amendment of overburden as a growing medium. The main objective of this study was to investigate and quantify the effects of inorganic and organic amendments and weathering on nutrient availability and plant growth in topsoil and overburden material obtained from the OceanaGold Globe Progress mine at Reefton, New Zealand. A series of glasshouse experiments were carried out on topsoil, fresh overburden and mullock (old waste rock) amended with biosolids, green manure, sawdust, lime and mineral fertiliser nutrients (nitrogen (N) and phosphorus (P)). R esults demonstrated that 300 kg N ha⁻¹ was sufficient to overcome N deficiency in topsoil, while 100 kg P ha⁻¹ was required to overcome P deficiency. Addition of biosolids to topsoil and overburden increased plant biomass production, without increasing heavy metal concentrations. Amendment of overburden significantly affected weathering rates by accelerating the formation of secondary minerals. In particular, lupin green manure accelerated the formation of organic iron (Fe) and aluminium (Al) organic complexes, resulting from the decomposition of the green manure and release of Fe from primary minerals. Results revealed that wineberry and red beech required 200 kg N ha⁻¹ for optimum growth. Overall, the findings of this research identified key parameters for effective utilisation of overburden as a restoration substrate. A sustainable restoration method for managing the topsoil and/or any overburden or waste rock material remaining at mine sites can be achieved by careful selection of organic amendments and allowing an initial weathering period.

Cette thèse porte sur l’impact du type de sol sur le fonctionnement biogéochimique d’un écosystème forestier typique d’Europe centrale et occidentale. Pour cette étude, un dispositif expérimental a été mis en place par l’INRA et l’ANDRA au sein d’une hêtraie (Fagus sylvatica) dans la forêt de Montiers-sur-Saulx (Meuse, France) afin de suivre les cycles biogéochimiques entre les différents compartiments de l’écosystème (l’atmosphère, la canopée, la litière et le sol). L’intérêt particulier du site expérimental de Montiers vient du contraste important entre les types de sols pour un même peuplement : rendisol, calci-brunisol et alocrisol/brunisol. Pour la première fois, les stocks et les flux de l’eau et des éléments ont été mesurés et comparés in situ et sur le long terme (entre janvier 2012 et décembre 2015) sur des sols forestiers différents, toutes les autres conditions du site égales par ailleurs (climat, apports atmosphériques, âge et structure du peuplement). Les stocks totaux et échangeables dans le sol et les stocks dans les différents compartiments de la biomasse végétale (branches, tronc, racines grosses et fines) ont été déterminés par le biais d’analyses chimiques et de modélisations. Les flux élémentaires ont été calculés à partir des prélèvements mensuels des solutions de l’écosystème (dépôt atmosphérique, pluviolessivat, écoulement de tronc, solutions libres et liées du sol) et des chutes de litière. Le modèle hydrique BILJOU© a été utilisé pour estimer les composantes du bilan hydrique de l’écosystème. Les résultats montrent que la réserve utile du sol, les stocks des éléments dans le sol, les compositions chimiques des solutions du sol, la stratégie de colonisation racinaire et la production de biomasse pérenne diffèrent fortement en fonction du type de sol. Contrairement à ce que l’on pouvait supposer compte tenu des différences marquées entre les signatures chimiques des solutions des trois sols, les compositions foliaires du peuplement et les flux des éléments hors sol en solution (échange de la canopée, apport au sol) et sous forme solide (chute de litière) ne diffèrent pas ou peu entre les trois stations expérimentales pour la majorité des éléments. La part biologique des cycles minéraux est globalement prédominante et le renouvellement des racines fines représente un flux de recyclage généralement supérieur à la chute de litière aérienne. Nous montrons également que la quantité d’eau transpirée par la canopée, directement liée à la taille de la réserve utile du sol, est le facteur de contrôle principal de la productivité du peuplement à l’échelle annuelle. Des processus d’adaptation du peuplement aux conditions physico-chimiques du sol semblent réduire, voire compenser entièrement, les facteurs secondaires de contrôle de la productivité du peuplement (notamment la disponibilité des nutriments dans le sol). Ainsi un enjeu significatif pour les gestionnaires forestiers pourrait être l’adaptation des pratiques sylvicoles à des parcelles de gestion davantage basées sur les propriétés physiques des sols, et en particulier les profondeurs d’apparition de la roche-mère et de colonisation racinaire / This thesis deals with the impact of soil type on the biogeochemical functioning of a typical forest ecosystem of Central and Western Europe. For this study, a strongly instrumented experimental site was implemented in a beech stand (Fagus sylvatica) within the state forest of Montiers-sur-Saulx (Meuse, France), in order to monitor the biogeochemical cycling between the different compartments of the ecosystem (the atmosphere, the canopy, the forest floor and the soil). The particular value of the Montiers experimental site resides in the strong contrast between soil types under the same beech stand: Rendzic Leptosol, Eutric Cambisol and Dystric Cambisol. For the first time, stocks and fluxes of water and elements were measured and compared in situ and over the long term (from January 2012 to December 2015) on different forest soil types, all other site conditions being equal (climate, atmospheric inputs, stand age and structure). Total and exchangeable pools in the soil and stocks in the different compartments of the vegetation (branches, trunk, fine and coarse roots) were determined via chemical analysis and modelisation. Fluxes of elements were calculated from monthly sampling of the ecosystem’s solutions (atmospheric deposition, throughfall, stemflow, gravitational and bound soil solutions) and of litter fall. The water balance model BILJOU© was used to estimate the different components of the water budget. The results show that the soil water holding capacity, the stocks of elements in the soil, the chemical composition of soil solutions, the rooting strategy and the perennial biomass production differ strongly between soil types. Contrary to what might have been expected in regard to the marked differences between the chemical signatures of the soils solutions in the three soils, the foliar elemental composition of the beech stand and the aboveground fluxes of elements in solution (canopy exchange, stand deposition) and in solid state (litter fall) do not differ significantly between the three experimental stations for the majority of the studied elements. The biological part of the mineral cycles is overall predominant and the recycling through fine roots turnover is generally higher than litter fall. We also show that the quantity of water transpired by the forest canopy, directly linked to the soil water holding capacity, is the primary control factor of the annual stand productivity. Stand adaptation mechanisms to physico-chemical soil properties seemed to reduce, or even entirely compensate for, secondary factors controlling the stand productivity (in particular nutrient availability in the soil). Thus a significant issue for forest managers might be to further adapt forestry practices to management units based on soil physical properties, especially depth to the bedrock and rooting depth