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Effects Of Large Wood Additions On Basal Resources, Macroinvertebrates, And Ecosystem Processes In The Narraguagus River, Maine, Val Watson

Electronic Theses and Dissertations

Ecological restoration is an increasingly common practice across ecosystems, and current practices aim to restore the biological and physical processes underlying ecosystem function, often for the sake of endangered higher-level consumers. Studies of restoration outcomes often report few or inconsistent ecological changes, and monitoring of restoration projects rarely measures ecological processes. Monitoring also usually measures outcomes at a single scale, despite the prevalence of scale- dependent phenomena across ecosystems. My thesis uses measurements of ecological processes to assess restoration response and evaluates responses across multiple scales. I focus here on a long-term large wood addition project on the Narraguagus River …

Form And Risk Class Distribution And Its Effect On Estimated Product Ratios In Commercial Species Commonly Found In Northeastern Forests And A Comparative Analysis Of Contrasting Field Inventory Methodologies, Ryan Smith

Electronic Theses and Dissertations

Estimating product ratios in hardwood forests is difficult due to the highly complex stem forms and diverse growth and regeneration strategies found in hardwood species. This is of particular concern for landowners with large ownerships requiring robust product potential estimates as part of both short-term tactical harvest planning and long-term growth and yield projections. Hardwood-dominated forests are generally managed for high-value sawlog and veneer products. This makes it increasingly important to identify strategies for improving hardwood management to meet economic (maximizing sawlog recovery) and ecological (maintaining healthy and diverse forests) goals.

This study seeks to achieve two primary goals. The …

Evaluation Of Airborne Lidar As A Tool For Obtaining Sustainable Forest Management Of Maine's Forests, Rei Hayashi

Electronic Theses and Dissertations

The first objective of this study was to evaluate the applicability of using a low density (ca. 1 point m􀀀2) discrete-return LiDAR for predicting maximum tree height, stem density, basal area, quadratic mean diameter, and stem volume using an area-based approach. The research was conducted at the Penobscot Experimental Forest in central Maine, where a range of stand structures and species composition is present and generally representative of northern Maines forests. Using a variety of high dimensional LiDAR metrics, a prediction model was developed using random forest, a nonparametric approach, based on reference data collected in fixed radius circular plots. …

Production Ecology And Stand Dynamics Of Young Acadian Forest Stands In Response To Silvicultural Intensity And Compositional Objectives, Andrew S. Nelson

Electronic Theses and Dissertations

Early successional stands are common across the Acadian forests of eastern Canada and the Northeastern US. However, productivity and dynamics of these stands, as well as the underlying mechanisms influencing these processes, under different management scenarios are poorly understood. To address this need, I used a factorial experiment that controlled silvicultural intensity and species composition to quantify the effects of varying treatments on early stand dynamics, and the physiological and morphological factors influencing tree performance . Specifically, I studied: 1) species differences in aboveground allometrics, 2) light capture, light-use efficiency (LUE; growth/light capture), and foliar carbon isotope composition (δ13C) of …

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 …