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Full-Text Articles in Life Sciences
Native And Non-Native Ant Impacts On Soil Microbes, Hannah A. Stewart
Native And Non-Native Ant Impacts On Soil Microbes, Hannah A. Stewart
Biology Theses
Organisms produce chemical weapons for defense, but target organisms can develop resistance. In their introduced range, non-native species may bring “novel weapons” against which native organisms have not co-evolved resistance. The invasive European fire ant (Myrmica rubra) may have brought antimicrobial secretions to the Northeastern United States that are novel weapons against native fungal and bacterial soil organisms. I hypothesized that M. rubra would better inhibit seed pathogens resulting in greater emergence of native myrmecochorous Viola sororia seeds and, as a side effect, more strongly inhibit arbuscular mycorrhizal fungi than a native seed dispersing ant (Aphaenogaster picea …
Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr.
Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr.
Biology Theses
Invasive plants often dominate novel habitats where they did not co-evolve with local species. Several hypotheses suggest mechanisms that explain increased exotic plant success, including 'novel weapons' and 'degraded mutualisms'. Japanese knotweed (Fallopia japonica) and European buckthorn (Rhamnus cathartica) are widespread plant invaders in North America that can dominate ecosystems. The goal of this study is to test whether these impacts are more consistent with novel weapons or degraded mutualism hypotheses. I examine tree seedling recruitment, (germination and initial survival) growth, (biomass) and mycorrhizal invasion (AMF content) as a function of F. japonica and R. cathartica …
Forest Sustainability In An Altered Landscape Requires Human Intervention, Adam C. Labatore
Forest Sustainability In An Altered Landscape Requires Human Intervention, Adam C. Labatore
Biology Theses
Recruitment success determines the abundance and composition of plant communities. Successful recruitment can be summarized as a simple dichotomy of establishment versus seed limitations. Establishment limitation occurs when plant populations are inhibited by habitat availability and quality, whereas seed limitation occurs when seeds fail to arrive in necessary densities. Recruitment failure undermines overstory sustainability if the existing trees cannot replace themselves. Preliminary analysis indicated tree recruitment failure at an urban nature preserve with too few tree seedlings to replace mature canopy trees. These data suggested that the urban forest was not sustainable. The overarching goal of the study was to …
Influence Of Nitrogen And Phosphorus On Ecosystem Co2 Exchange In A Restored Temperate Grassland, Lynn M. Socha
Influence Of Nitrogen And Phosphorus On Ecosystem Co2 Exchange In A Restored Temperate Grassland, Lynn M. Socha
Biology Theses
Nitrogen (N) and phosphorus (P) affect the structure and function of grasslands by altering plant competitive interactions, shifting patterns of above- and belowground biomass allocation, and by increasing net primary production. However, the influence of N and P on net ecosystem productivity is poorly understood. In the context of a field-based factorial N- and P-addition experiment, I measured soil moisture, leaf area index and component fluxes of ecosystem CO2 exchange throughout the growing season in a restored temperate grassland near Buffalo, New York. I predicted that N-addition would enhance ecosystem CO2 uptake (GEE) while P-addition would stimulate ecosystem …