Thesis (Ph. D.)--University of Alaska Fairbanks, 2005. / "May 2005." Includes bibliographical references. Also available in electronic format via Internet.

Thesis (M.Sc.)--Memorial University of Newfoundland, 2002. / Bibliography: leaves 144-155.

Thesis (M.Sc.) -- Memorial University of Newfoundland. / Typescript. Bibliography: leaves 106-115. Also available online.

Thesis (Ph.D.)--Memorial University of Newfoundland, 2005. / Includes bibliographical references.

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2003. / Appendix consists of reproductions of six papers and manuscripts, five co-authored with others. Thesis documentation sheet inserted. Includes bibliographical references. Issued also electronically via World Wide Web in PDF format; online version lacks appendix of papers.

The cover of the ericaceous shrub Kalmia angustifolia L. (sheep's laurel or lamb's kill) expands rapidly on many clear-cut sites through central Newfoundland and northern Quebec. Previous laboratory and greenhouse studies on the effect of Kalmia on black spruce (Picea mariana (Mill.) B.S.P.) germinants and seedlings have demonstrated that extracts of Kalmia leaves and soil can reduce the germination rate and early root and shoot growth of black spruce. Observations in the field have suggested that Kalmia leaves and soil can reduce the germination rate and early rot and shoot growth of black spruce. Observations in the field have suggested that Kalmia reduces the growth of planted spruce seedlings. The experiments presented in this thesis were designed to determine the importance of Kalmia in controlling spruce growth and nutrition, and to document how the importance of Kalmia varies from site to site. Spruce seedlings growing in close proximity to Kalmia were found to be shorter and had lower foliar concentrations of N and P, and the roots of these seedlings had lower rates of mycorrhization and a more frequent occurrence of the pseudo-mycorrhizal/pathogenic fungus Phialocephala dimorphospora Kendrick. Results suggest that Kalmia impedes the N nutrition of spruce seedlings through the reduction of N mineralization rates and N availability. The results of path analysis further suggest that Kalmia had a direct effect on both spruce foliar N concentration and spruce growth. These findings do not demonstrate, though they are consistent with the suggestion, that Kalmia can affect spruce through allelopathic processes. Although we could not demonstrate that the reduction of rates of mycorrhization were due to indirect effects of Kalmia on spruce nutrition, we demonstrated that improving spruce nutrition in close proximity to Kalmia increased, though not significantly, the occurrence of mycorrhizae on spruce roots. Mycorrhizal symbiosis was shown to play a key role in t

No description available.

No description available.

This study examines the impact of snowmelt runoff on nutrient transfer from the terrestrial to the aquatic (lake) portion of a subarctic catchment 6 km WSW from Schefferville, Quebec. / Statistically significant differences in snow chemistry were recorded among the tundra, woodland and forest snowpacks. Significant overland substantial scouring of nutrients from the organic horizons were recorded in the tundra, woodland and forest. A calculation designed to generate, on a daily basis, 70% of the meltwater from the terrestrial catchment to the lake indicates overland flow is a predominant route of meltwater during the spring. This calculation made possible the determination of daily nutrient mass transfer from land to lake. The daily nutrient mass balance of input and output to Elizabeth Lake during springmelt indicates significant retention of land source nutrients. Deuterium/hydrogen measurements aided in determining mixing of snowmelt and lake water. The data indicate snowmelt water is undistinguishable from lake water at depths greater than 1.0 m. / It is concluded that snowmelt runoff is an important event for nutrient transfer from terrestrial to aquatic systems in this environment.

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2007. / Thesis documentation sheet inserted. Includes appendix of four papers and manuscripts, three co-authored with others. Includes bibliographical references. Also issued electronically via World Wide Web in PDF format; online version lacks appendix.