Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 17 of 17 for “"environmental filtering"”.
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Ecological assembly of high-diversity plant communities: dispersal, competition, and environmental filtering in longleaf pine savannas
… between species-pool diversity and local environmental heterogeneity. My results suggest a conceptual model for community assembly in high-diversity pine savannas, with implications for other species-rich plant communities. I propose that characteristics of high-diversity communities …
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Intraspecific trait variation and community assembly in old-field grasslands
… assembly and responses to spatial and temporal environmental variation in old-field plant communities in the eastern United States. In the first study I analyzed spatial patterns of functional divergence in old fields in central New York on spatial scales from 1-1500 m. Results showed that …
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A mechanistic framework for understanding prairie stream fish distributions
A fundamental goal of ecology is to understand environmental associations of species. These associations can provide a basis for predicting spatial distributions in contemporary habitats as well as how those distributions might change in response to anthropogenic environmental change. Developing …
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Consequences of drought, flooding, and insect herbivory on the distributions of closely related willow and poplar (Salicaceae) species across hydrologic gradients in Minnesota wetlands
… that known to influence beta diversity is environmental filtering. Besides environmental filtering, biotic interactions can also affect beta diversity, if biotic factors exert differential effects on species performances across environmental gradients. Contributions of different community …
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Recovery and Resilience of Appalachian Herbs
… abundance, composition, spatial patterns, environmental filtering and trait based species assembly. The results demonstrate that understory herb communities do not return to their pre-disturbance states even after over a century of recovery in nearly all important respects. Both species …
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The role of dispersal networks in structuring biotic communities: A tale of streams and metacommunity theory
… ecology. Locally operating mechanisms such as environmental filtering, in which the environment determines what species are found in a given location, as well as regional processes such as dispersal have all been identified as potential drivers of community processes. However, the relative …
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Effects of soil nutrient availability on the development of tropical monodominance and subordinate species composition in montane forests
… that the plant-soil feedback imposed additional environmental filtering on the tree community. However, the capacity to generate plant soil feedback is itself a consequence of an “exceptional trait”, the presence of ectomycorrhizal fungi associations in Oreomunnea-dominated forests, in a …
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A Spatio-temporal Phylogenetic Approach to Community Ecology
… small spatial scales, which then transitions to environmental filtering at broad spatial scales. Therefore studies which select communities at a fixed spatial size are biased toward observing certain patterns and may subsequently overlook spatially-dependent processes. Finally, for angiosperm …
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Linking plant traits and herbivory in grassland biodiversity-ecosystem functioning research
… or sheep. This result indicates that environmental filtering structures these communities more than limiting similarity. Extending the use of traits beyond the study system in Inner Mongolia, I test the how both functional and phylogenetic diversity explain the biodiversity effect on …
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Spatiotemporal Variation in Dispersal as a Driver of Macroinvertebrate Metacommunity Dynamics
… local processes such as species competition and environmental filtering. Metacommunity theory, however, highlights regional drivers such as dispersal and connectivity as key structuring forces. The mechanisms governing freshwater macroinvertebrates community assemblage have long been studied due …
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Trait-based approaches to understanding the response of forest understory herbs to environmental variation
… and communities will respond to future environmental change. Trait-based approaches can thus offer valuable insights into how populations and communities will respond to environmental change by providing a mechanistic link between plant traits and the environment. This dissertation …
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The Genomics of Divergence and Adaptation in Sister Reef Fishes Separated by the Isthmus of Panamá
… the genetic basis of adaptation to changing environmental conditions is challenging. This is especially true in marine systems where connectivity between populations may be high and past conditions difficult to reconstruct. The emergence of the Isthmus of Panamá provides a unique, natural …
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The Effect of Spatial and Environmental Drivers on Patterns in Species Richness and Composition
… time related components including speciation and environmental change. Oceanic islands are not stable systems but follow a characteristic ontogeny. After the volcanic emergence over the sea surface, erosion processes, shaping the island first more heterogeneous and then flatter, transform islands. …
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Microbiome-centered Approaches to Marine Disturbance Ecology
… disturbances were not clearly linked to specific environmental changes and did not exhibit common responsive taxa. Further, a category 1 hurricane, the only event that would likely be classified a priori as an environmental disturbance, was not an outlier in microbiome composition, but did enhance …
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Ant diversity across an elevational gradient; functional versus taxonomic perspectives in the Soutpansberg Mountains, South Africa
… way of life and sensitivity to habitat change. Environmental gradients are central in our attempt to address these shortfalls gauging these organisms' responses to environmental change and ultimately in the search for general rules of community assembly. In this study I focus on ants in a …
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COMMUNITY STRUCTURE AND FUNCTIONAL DIVERSITY OF IMPERILED GREAT PLAINS FISHES: IMPLICATIONS FOR CONSERVATION OF TWO ENDANGERED SHINERS (SHARPNOSE SHINER NOTROPIS OXYRHYNCHUS AND SMALLEYE SHINER NOTROPIS BUCCULA) IN THE UPPER BRAZOS RIVER, TEXAS
<p>Anthropogenic practices such as groundwater pumping, land use change, and the implementation of dams have caused significant change in freshwater ecosystems, especially in the Great Plains of North America where pelagic broadcast spawning fish species are declining due to the loss of the natural …
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The population and community ecology of small freshwater ponds: Assigning process to pattern
Ecologists have long been intrigued by patterns of spatial structuring for populations and communities inhabiting natural and, more recently, human-created ecosystems. Empirical and theoretical advancements have highlighted the importance of considering the effects of both historical (i.e., …