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Full-Text Articles in Life Sciences
Study Of Basic Wood Decay Mechanisms And Their Biotechnological Applications, Yuhui Qian
Study Of Basic Wood Decay Mechanisms And Their Biotechnological Applications, Yuhui Qian
Electronic Theses and Dissertations
The overall objective of this thesis was to gain further understanding of the non-enzymatic mechanisms involved in brown-rot wood decay, especially the role of pH, oxalic acid, and low molecular catecholate compounds on the dissolution and reduction of iron, and the formation of reactive oxygen species. Another focus of this study will be the potential application of a biomimetic free radical generating system inspired from fungi wood decay process, especially the non-enzymatic mechanism. The possible pathways of iron uptake and iron redox cycling in non-enzymatic brown-rot decay were investigated in this study. UV-Vis spectroscopy and HPLC were employed to study …
The Effects Of Chronically Elevated N And S Deposition On The Nutrition And Physiology Of Sugar Maple At The Bear Brook Watershed In Maine, Suzanne Bethers
The Effects Of Chronically Elevated N And S Deposition On The Nutrition And Physiology Of Sugar Maple At The Bear Brook Watershed In Maine, Suzanne Bethers
Electronic Theses and Dissertations
The Bear Brook Watershed in Maine is a paired watershed system; one watershed has been acidified bimonthly with granular ammonium sulfate ((NH4)2SO4) since 1989. The adjacent watershed is used as a reference. This acid deposition treatment presents unique opportunities to look at the long term affects of acidification on vegetation. Acidic deposition continues to be a concern for the health of sugar maple (Acer saccharum Marsh.) in northern hardwood forests. Many studies show a connection between base cation depletion induced by acid deposition and sugar maple decline. In this text we …
Relative Fitness And Behavioral Compensation Of Amphibians In A Managed Forest, Sean Michael Blomquist
Relative Fitness And Behavioral Compensation Of Amphibians In A Managed Forest, Sean Michael Blomquist
Electronic Theses and Dissertations
Habitat loss and degradation are two of the most important factors leading to the imperilment of species worldwide including amphibians, but mechanisms underlying these changes are poorly understood. To understand the fitness potential of harvested forests, I conducted studies of a forest specialist, Rana sylvatica (Wood Frogs) and compared these results with those from identical studies with an open canopy specialist, R. pipiens (Northern Leopard Frogs) in response to an unharvested control and three forest harvesting treatments: clearcutting (with removal of all merchantable timber > 10 cm diameter), clearcutting with coarse woody debris retention, and partial harvesting with removal of < 25% canopy cover. First, I used radio-telemetry data collected on 72 adult R. …
Using Dendrochronology To Understand The Response Of Eastern Hemlock To Past Stresses And Its Current Status In Southern Maine, Sophia Demaio
Using Dendrochronology To Understand The Response Of Eastern Hemlock To Past Stresses And Its Current Status In Southern Maine, Sophia Demaio
Electronic Theses and Dissertations
Eastern hemlock (Tsuga canadensis (L.) Carr.) is an ecologically important species that is threatened across its range by the non-native hemlock woolly adelgid (HWA, Adelges tsugae (Annand) (Hemiptera: Adelgidae)). In order to understand potential impacts of HWA in southern Maine, we conducted a treering study of 36 sites in southern Maine (York and Cumberland counties) to evaluate how stress events affected eastern hemlock increments, especially after the 1999-2002 drought. The primary objectives were to: 1) create a master chronology and identify reduced growth events 2) model abiotic factors associated with differences in drought response among plots and 3) evaluate the …