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Full-Text Articles in Life Sciences
The Effects Of Anthropogenic Stress On Nitrogen-Cycling Microbial Communities In Temperate And Tropical Soils, George S. Hamaoui Jr.
The Effects Of Anthropogenic Stress On Nitrogen-Cycling Microbial Communities In Temperate And Tropical Soils, George S. Hamaoui Jr.
Doctoral Dissertations
In this dissertation several research studies are discussed that characterize the effects of anthropogenic, or human-induced, stress on both ammonia-oxidizing and total bacterial soil microbial communities. The disturbances of land-use change in tropical, South American rainforests and artificial warming and nitrogen (N) fertilization in temperate, North American forests were investigated as these disturbances represent past and current disturbances caused by human landscape alteration and climate change. Initially, the response of soil ammonia-oxidizing microbial communities to land-use change from primary rainforest to pasture and, finally, back to secondary forest was determined. Next, these analyses of land-use change effects were expanded to …
Understanding The Complex Relationships Between Climate, Vegetation, And Foraging Behavior Of A Climate-Sensitive Alpine Mammal In Order To Explain Patterns Of Persistence, Evan Cole
Master's Projects and Capstones
Mountain ecosystems offer substantial ecosystem services but are highly sensitive to climate change. The American pika (Ochotona princeps) serves as an indicator species of climate change and a model organism for studying its impacts on mountain mammals. Certain aspects of plant community composition and structure can function as predictors of pika distribution, but understanding the links between climate, forage quality, and foraging behavior is necessary to identify the mediating mechanism. Pika foraging pressure help shape the local plant community, which can confound modeling efforts and must be considered when evaluating the influence of vegetation on pika persistence. Plant …
Limited Evidence For Co2-Related Growth Enhancement In Northern Rocky Mountain Pinus Contorta Populations: Trends In Growth And Intrinsic Water-Use Efficiency Across Climate Gradients, Charlotte C. Reed
Graduate Student Theses, Dissertations, & Professional Papers
Forests sequester large amounts of carbon annually; however, the degree to which enhanced forest productivity is due to more conducive climate or CO2 fertilization remains uncertain. Increasing atmospheric CO2 may enhance photosynthesis and/or decrease stomatal conductance thereby enhancing intrinsic water use efficiency (iWUE). While increasing iWUE has been observed in most trees globally, this increase does not necessarily translate into greater growth. This study aims to evaluate whether responses of radial growth and iWUE to increasing CO2 vary across climatic gradients. To investigate interactions between climate and CO2 and their impacts on tree physiology and growth, …