In the present century, ecosystems across the globe will be subject to profound changes in climate. Forests are expected to be particularly sensitive to such change as the long life span of trees limits the potential for rapid adaptation. In order to preserve commercial viability and the essential ecosystem services provided by forests, there has been much interest in strategies for managing the adaptation of trees to their climatic environment. Climate Matching has emerged as one such strategy, whereby climate models are used to identify provenances – tree populations at a particular locality - with seed expected to be well adapted to the future conditions of a particular planting site. Debate continues about the feasibility and merit of this and other approaches, but it has yet to be demonstrated that the underlying assumptions of Climate Matching are valid for focal European tree species. Furthermore, a potentially major omission thus far has been consideration of how the Climate Matching strategy might influence associated organisms. Given the widely demonstrated bottom-up effects of foundation species genotype that have emerged from the field of community genetics, it is possible that planting seed of non-local provenance could effect forest organisms such as insect herbivores. In this thesis, I investigate the underlying assumptions of Climate Matching and its community level consequences using a model system of cynipid oak galls on Quercus petraea. Following a general introduction to Climate Matching and the study system, in Chapter 2 I use data from a provenance trial of Q. petraea in France to explore a central assumption of the Climate Matching strategy: that provenances of focal tree species show climate associated variation in adaptive phenotypic traits. In Chapter 3, I explore correlations between these phenotypic traits and the abundance, diversity, and community composition of an associated guild of specialist gall-inducing herbivores. Tree phenological traits in particular showed strong patterns of adaptation to climatic gradients, and influenced the abundance and community structure of galling species. However, as the response to non-local tree provenances was not strongly negative, it was considered unlikely that mixed planting of local and Climate Matched provenances would have sever impact on the gallwasp community. Having assessed the bottom-up effects of provenance phenotypic variation on the galling community, my ultimate aim is to extend analysis to include associated hymenopteran inquilines and parasitoids. However, interpretation of effects at this level is hindered by taxonomic uncertainty, with a growing appreciation that morpho-taxa may not represent independently evolving lineages (i.e. ‘true’ species). In Chapters 4 & 5 I therefore develop approaches for addressing taxonomic uncertainty with this ultimate aim in mind. In Chapter 4, I apply a DNA barcoding approach to parasitoid and inquiline specimens reared from the provenance trial, and compare taxa based on barcodes with those based on morphology to identify points of taxonomic uncertainty. I also investigate the extent to which networks based on morphological and molecular taxa support contrasting conclusions of network properties. In Chapter 5 I explore the potential for molecular based resolution of species level taxonomic error in a challenging group of parasitoids: the genus Cecidostiba. Beginning with a framework of single locus DNA barcoding, I use data from multiple nuclear loci to reveal the existence of cryptic species. Finally, in Chapter 6 I explore the practicalities of Climate Matching in light of my empirical results, and suggest fruitful avenues for further research.

Aim: The abundances and distributions of some species are more closely matched to variations in climate than others. Species traits that might influence how well the distribution and abundance of a species are matched to climatic variation include life history (e.g., body size and dispersal ability), ecology (e.g., habitat specialization and territoriality) and demography (e.g., population size). Here, we used a survey of bird abundances across the USA to assess the extent to which species abundances and distributions are predicted by climate (i.e., climate matching) and how species traits relate to interspecific variation in climate matching. Location: USA. Time period: 1983–2018. Major taxa studied: Birds. Methods: Species abundances were obtained from the North American Breeding Bird Survey. Climate matching was estimated as the predictive performance of species–climate models fitted using boosted regression trees and generalized additive models and modelled as a function of species traits. Results: Species traits explained 56% of the variation in climate matching among species. Intermediate-sized species were more well matched to climate than smaller or larger species, as were species that lived primarily in forested compared with open habitats, species that were locally more abundant and species that were more territorial. Alternatively, species that were more specialized or had high variability in abundance among sites were less well matched to climate. We also found that species classified as “near threatened” were more well matched to climate, suggesting that these species might be more vulnerable to climate change. However, species classified as “vulnerable” were more decoupled from climate than those of “least concern”, possibly owing to ecological drift associated with progressive population declines. Main conclusions: Our findings provide an ecological basis for understanding the extent to which species abundances and distributions match broad climatic gradients, which can provide the groundwork to improve our ability to predict distributions under global change.

Made available in DSpace on 2014-12-17T14:33:05Z (GMT). No. of bitstreams: 1 BrunnoFDO_DISSERT.pdf: 1072437 bytes, checksum: ca0f1130c794e389077757530d1d5b66 (MD5) Previous issue date: 2012-02-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Based on climate data and occurrence records, ecological niche models (ENM) are an important opportunity to identify areas at risk or vulnerable to biological invasion. These models are based on the assumption that there is a match between the climatic characteristic of native and invaded regions predicting the potential distribution of exotic species. Using new methods to measure niche overlap, we chose two exotic species fairly common in semi-arid regions of South America, Prosopis juliflora (Sw.) D.C. and Prosopis pallida (H. ; B. ex. Willd) HBK, to test the climate matching hypothesis. Our results indicate that both species occur with little niche overlap in the native region while the inverse pattern is observed in the invaded region on South America, where both species occur with high climatic overlap. Maybe some non-climate factor act limiting the spread of P. pallida on the native range. We believe that a founder effect can explain these similarities between species niche in the invaded region once the seeds planted in Brazil came from a small region on the Native range (Piura in Peru), where both species occur sympatric. Our hypothesis of a founder effect may be evident when we look at the differences between the predictions of the models built in the native and invaded ranges. Furthermore, our results indicate that P. juliflora shows high levels of climate matching between native and invaded ranges. However, conclusions about climate matching of P. pallida should be taken with caution. Our models based on climatic variables provide multiple locations suitable for occurrence of both species in regions where they still don t have occurrence records, including places of high interest for conservation. / Baseados nas informa??es clim?ticas e nos registros de ocorr?ncia, modelos de nicho ecol?gico (MNE) s?o uma importante oportunidade de identificar ?reas sob risco ou vulner?veis ? invas?o biol?gica. Estes modelos se ap?iam na suposi??o de que existe congru?ncia entre os climas das regi?es nativa e invadida para prever a distribui??o potencial de esp?cies ex?ticas. Utilizando m?todos recentes para medir sobreposi??es entre MNE, escolhemos duas esp?cies invasoras bastante comuns em regi?es semi-?ridas da Am?rica do Sul, Prosopis juliflora (Sw.) D.C. e Prosopis pallida (H. ; B. ex. Willd) H.B.K., para testar a hip?tese da congru?ncia clim?tica. Nossos resultados indicam as duas esp?cies ocorrem com pouca sobreposi??o de nicho na regi?o nativa, enquanto que o inverso se observa na regi?o invadida na Am?rica do Sul, onde as duas esp?cies ocorrem com elevada sobreposi??o de nicho. Algum fator n?o clim?tico pode atuar limitando a dispers?o de P. pallida na ?rea nativa. Acreditamos que um efeito fundador pode explicar estas semelhan?as de nicho encontradas na regi?o invadida uma vez que as sementes plantadas no Brasil vieram de uma pequena regi?o da ?rea nativa (Piura, Peru), onde ambas esp?cies ocorrem em simpatria. Diferen?as entre as previs?es dos modelos constru?dos na regi?o nativa e projetados para a regi?o nativa evidenciam nossa hip?tese do efeito fundador. Al?m disso, nossos resultados indicam que P. juliflora ocorre nas regi?es nativas e invadidas em condi??es clim?ticas bastante congruentes. Entretanto, conclus?es sobre congru?ncia clim?tica entre regi?es nativas e invadidas por P. pallida devem ser tomados com cautela. Os modelos prev?em v?rios locais favor?veis para a ocorr?ncia de ambas as esp?cies em regi?es onde ainda n?o existem registros de ocorr?ncia, inclusive locais de elevado interesse para conserva??o.

Invasive exotic species threaten the biodiversity and function of native ecosystems. Existing models, attempting to predict and control successful invaders, often emphasize isolated stages of in their life history and fail to formalize interactions between exotic species and recipient environments. In order to elucidate key mechanisms in the success of select invaders, I investigated the role of dispersal, establishment, proliferation, and persistence in their threat to natural areas. Focusing on Riding Mountain National Park, Manitoba, Canada, I integrated the native climatic range and biological traits of 251 exotic vascular plants reported inside and outside the park. Based on their climatic range in Europe, 155 among 174 exotic plant species absent from the Park were predicted to establish within its boundaries; among these, 40 clonal perennials were considered the highest threat to the Park’s biodiversity. Focusing on smooth brome (Bromus inermis Leyss.), a Eurasian perennial, threatening the structure and function of native prairies throughout the Great Plains, I extended my research to investigate the role of dispersal, establishment, proliferation, and persistence in characterizing its threat to the endemic diversity of northern fescue prairies, protected within Riding Mountain National Park. Patterns of smooth brome invasions were contingent on the type of propagules dispersed. The shallow dispersal gradient of individual florets combined with the steeper gradient of panicles and spikelets suggested that smooth brome is capable of simultaneously invading along dense fronts as well as by establishing isolated foci. While low correlations between the number of dispersed seeds and their recruitment suggested post-dispersal transport, seedling establishment remained contingent on prairie diversity. Seedling biomass increased with declining plant diversity, however, its impact depended on the availability of soil nitrogen. As a result, disturbed areas, preserving the root function of native plants, resisted smooth brome establishment. Even though low nitrogen contributed to a decline in seedling biomass, physiological integration between ramets facilitated their vegetative proliferation in low resource environments. Despite its rapid establishment and proliferation, smooth brome productivity declined at the center of invading clones. Although field and greenhouse observations failed to implicate soilborne pathogens, reasons for the observed decline remain unresolved. My research demonstrates that while Riding Mountain National Park and other natural areas in western Canada will continue to be impacted by exotic plants, integrating key stages in their life history provides an important conceptual framework in predicting their threat to natural areas and prioritizing management. / October 2008

Invasive exotic species threaten the biodiversity and function of native ecosystems. Existing models, attempting to predict and control successful invaders, often emphasize isolated stages of in their life history and fail to formalize interactions between exotic species and recipient environments. In order to elucidate key mechanisms in the success of select invaders, I investigated the role of dispersal, establishment, proliferation, and persistence in their threat to natural areas. Focusing on Riding Mountain National Park, Manitoba, Canada, I integrated the native climatic range and biological traits of 251 exotic vascular plants reported inside and outside the park. Based on their climatic range in Europe, 155 among 174 exotic plant species absent from the Park were predicted to establish within its boundaries; among these, 40 clonal perennials were considered the highest threat to the Park’s biodiversity. Focusing on smooth brome (Bromus inermis Leyss.), a Eurasian perennial, threatening the structure and function of native prairies throughout the Great Plains, I extended my research to investigate the role of dispersal, establishment, proliferation, and persistence in characterizing its threat to the endemic diversity of northern fescue prairies, protected within Riding Mountain National Park. Patterns of smooth brome invasions were contingent on the type of propagules dispersed. The shallow dispersal gradient of individual florets combined with the steeper gradient of panicles and spikelets suggested that smooth brome is capable of simultaneously invading along dense fronts as well as by establishing isolated foci. While low correlations between the number of dispersed seeds and their recruitment suggested post-dispersal transport, seedling establishment remained contingent on prairie diversity. Seedling biomass increased with declining plant diversity, however, its impact depended on the availability of soil nitrogen. As a result, disturbed areas, preserving the root function of native plants, resisted smooth brome establishment. Even though low nitrogen contributed to a decline in seedling biomass, physiological integration between ramets facilitated their vegetative proliferation in low resource environments. Despite its rapid establishment and proliferation, smooth brome productivity declined at the center of invading clones. Although field and greenhouse observations failed to implicate soilborne pathogens, reasons for the observed decline remain unresolved. My research demonstrates that while Riding Mountain National Park and other natural areas in western Canada will continue to be impacted by exotic plants, integrating key stages in their life history provides an important conceptual framework in predicting their threat to natural areas and prioritizing management.

Invasive exotic species threaten the biodiversity and function of native ecosystems. Existing models, attempting to predict and control successful invaders, often emphasize isolated stages of in their life history and fail to formalize interactions between exotic species and recipient environments. In order to elucidate key mechanisms in the success of select invaders, I investigated the role of dispersal, establishment, proliferation, and persistence in their threat to natural areas. Focusing on Riding Mountain National Park, Manitoba, Canada, I integrated the native climatic range and biological traits of 251 exotic vascular plants reported inside and outside the park. Based on their climatic range in Europe, 155 among 174 exotic plant species absent from the Park were predicted to establish within its boundaries; among these, 40 clonal perennials were considered the highest threat to the Park’s biodiversity. Focusing on smooth brome (Bromus inermis Leyss.), a Eurasian perennial, threatening the structure and function of native prairies throughout the Great Plains, I extended my research to investigate the role of dispersal, establishment, proliferation, and persistence in characterizing its threat to the endemic diversity of northern fescue prairies, protected within Riding Mountain National Park. Patterns of smooth brome invasions were contingent on the type of propagules dispersed. The shallow dispersal gradient of individual florets combined with the steeper gradient of panicles and spikelets suggested that smooth brome is capable of simultaneously invading along dense fronts as well as by establishing isolated foci. While low correlations between the number of dispersed seeds and their recruitment suggested post-dispersal transport, seedling establishment remained contingent on prairie diversity. Seedling biomass increased with declining plant diversity, however, its impact depended on the availability of soil nitrogen. As a result, disturbed areas, preserving the root function of native plants, resisted smooth brome establishment. Even though low nitrogen contributed to a decline in seedling biomass, physiological integration between ramets facilitated their vegetative proliferation in low resource environments. Despite its rapid establishment and proliferation, smooth brome productivity declined at the center of invading clones. Although field and greenhouse observations failed to implicate soilborne pathogens, reasons for the observed decline remain unresolved. My research demonstrates that while Riding Mountain National Park and other natural areas in western Canada will continue to be impacted by exotic plants, integrating key stages in their life history provides an important conceptual framework in predicting their threat to natural areas and prioritizing management.