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dc.contributor.advisorJohnstone, Jill F.en_US
dc.creatorFrey, Matthewen_US
dc.date.accessioned2013-10-02T12:00:10Z
dc.date.available2013-10-02T12:00:10Z
dc.date.created2013-09en_US
dc.date.issued2013-10-01en_US
dc.date.submittedSeptember 2013en_US
dc.identifier.urihttp://hdl.handle.net/10388/ETD-2013-09-1197en_US
dc.description.abstractWhile boreal forest habitats have historically been relatively free from invasive plants, there have been recent increases in the diversity and range of invasive plants in Alaska. It is critical that we understand how disturbances influence invasibility in northern boreal forests, to avoid the economic damage other regions have experienced from invasive plants. Black spruce (Picea mariana) is the dominant forest type in interior Alaska, and wildfire is the dominant disturbance in these forests. Furthermore, disturbances in the form of management for fire suppression are common in forests close to urban areas. I surveyed recently burned, managed, and undisturbed black spruce forests for invasive plants to determine if fire and management facilitate invasive plant colonization. I also conducted an experimental seeding trial with three invasive plants common to Alaska (bird vetch (Vicia cracca), common dandelion (Taraxacum officinale), and white sweetclover (Melilotus officinalis) in burned and mature black spruce forest to determine if fire facilitates invasive plant germination. To determine the effect of substrate type on invasive plant germination, I planted seeds on a variety of substrates in the burned forest. Results indicate that fire and fire suppression treatments promote invasive plant colonization, as invasive plants were observed in burned and managed areas, but not in mature stands. Analysis of environmental data taken at survey sites indicate that fire mediates invasibility through its effects on substrate quality. In burned stands, invasive plants are most likely to colonize areas of shallow post-fire organic depth. Results from the seeding trials were consistent with results from invasive plant surveys, with reduced germination in mature compared to burned forest, and no germination on the residual organic layer in the burned forest. The highest germination occurred on mineral soil in burned forest, indicating that severe fires that combust the organic layer are likely to increase invasibility. The results of this study suggest that invasive species control efforts should be prioritized to disturbed forests, particularly areas where the disturbance has exposed mineral soil.en_US
dc.language.isoengen_US
dc.subjectfireen_US
dc.subjectboreal foresten_US
dc.subjectinvasive planten_US
dc.subjectAlaskaen_US
dc.subjectblack spruceen_US
dc.subjecttaraxacumen_US
dc.subjectcrepisen_US
dc.subjectviciaen_US
dc.subjectmelilotusen_US
dc.titleDisturbance impacts on non-native plant colonization in black spruce forests of interior Alaskaen_US
thesis.degree.departmentBiologyen_US
thesis.degree.disciplineBiologyen_US
thesis.degree.grantorUniversity of Saskatchewanen_US
thesis.degree.levelMastersen_US
thesis.degree.nameMaster of Science (M.Sc.)en_US
dc.type.materialtexten_US
dc.type.genreThesisen_US
dc.contributor.committeeMemberLamb, Ericen_US
dc.contributor.committeeMemberSheard, Johnen_US
dc.contributor.committeeMemberDavis, Arten_US


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