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A Comparison Of The Ecological Integrity Of Headwater Streams Draining Harvested And Un-Harvested Watersheds In The Western Mountains Of Maine, U.S.A., Darlene Siegel Dec 2003

A Comparison Of The Ecological Integrity Of Headwater Streams Draining Harvested And Un-Harvested Watersheds In The Western Mountains Of Maine, U.S.A., Darlene Siegel

Electronic Theses and Dissertations

Physical, chemical, and biological characteristics of four headwater streams draining forested watersheds were compared to determine the effectiveness of Riparian Management Zones (RMZs) in protecting aquatic ecological integrity from the effects of forest harvesting. Two of the watersheds were harvested with a 30% sheltenvood cut and a 75 foot buffer was left adjacent to the streams. The other two watersheds were un-harvested and were used as reference conditions for comparison with the harvested watersheds. General environmental conditions in these four headwater streams during the study period were characterized as follows. Each stream was located within a mixed- wood forest dominated ...


Influence Of Firm Structure On Profitability In The U.S. Pulp And Paper Industry (1960-1998), Kanwar Muhammad Suleman May 2003

Influence Of Firm Structure On Profitability In The U.S. Pulp And Paper Industry (1960-1998), Kanwar Muhammad Suleman

Electronic Theses and Dissertations

This study indicates that firm size, market share and equity/sales ratio are the principal factors contributing to the profitability (net income) of pulp and paper firms in the United States. Timberland ownership, exports, K-Factor (a measure of relative firm capacity), growth, new supply/real gross domestic product (RGDP) ratio and price index also influence the profitability of pulp and paper manufacturing firms. Market share, an index of the structure of the pulp and paper industry, is determined by a firm's size (assets) and net income. In addition, the number of a firm's production units, K-factor, whether the ...


Effects Of Small-Gap Timber Harvests On Songbird Community Composition And Site-Fidelity, Mitschka John Hartley May 2003

Effects Of Small-Gap Timber Harvests On Songbird Community Composition And Site-Fidelity, Mitschka John Hartley

Electronic Theses and Dissertations

I investigated effects of small-gap timber harvests on bird communities at nine sites (10 ha each) within the Penobscot Experimental Forest (PEF), grouped into three replicated "blocks" (three sites each). Blocks were randomly treated with three treatments: 10% harvest, 20% harvest, and no harvest (i.e., control). I examined how treatments affected breeding songbird abundance, richness, and site-fidelity over four consecutive summers, including 1-3 years before and after each site was harvested. Ability to detect treatment effects was limited by the small number of replicates, but power analyses indicated that given the experimental design and observed variability, there was a ...


Effects Of Precommercial Thinning On Snowshoe Hares, Small Mammals, And Forest Structure In Northern Maine, Jessica A. Homyack May 2003

Effects Of Precommercial Thinning On Snowshoe Hares, Small Mammals, And Forest Structure In Northern Maine, Jessica A. Homyack

Electronic Theses and Dissertations

The extent of precommercial thinning (PCT) to manipulate stand density in overstocked, regenerating stands and to accelerate growth, yield, and the rate of development of crop trees has been increasing within the Acadian forest of northeastern North America. Although the silvicultural responses of crop trees to thinning are well studied, few studies have evaluated the effects of PCT on forest-dependent wildlife and their habitat. I investigated the effects of PCT and stand succession on snowshoe hares, small mammals, and forest structure on 38 stands (25 treated with PCT, 13 unthinned stands) from 1 to 16 years post-treatment within 7 townships ...


Future Of South Korean National Parks -- A Delphi Study, Byung-Kyu Lee Jan 2003

Future Of South Korean National Parks -- A Delphi Study, Byung-Kyu Lee

Electronic Theses and Dissertations

In a three-wave Delphi survey of a panel of 40 key experts of Korean National Parks conducted between February 2001 and March in 2002, four major issues -- (A) Park philosophy not clearly articulated; (B) Inadequate emphasis on ecosystem protection; (C) Widespread deficiency of management tools; and (D) Visitor services needed -- were asked to get the panel's opinions regarding 'importance' (1 = most important; 4 = least important) and 'likelihood' of being resolved (1= resolved in 5 years; 4 = not resolved in 5 years) of these four issues in Wave 3. In terms of 'importance,' Issue A (Park philosophy not clearly articulated ...


Long-Term Effects Of Herbicide And Precommercial Thinning Treatments On Species Composition, Stand Structure, And Net Present Value In Spruce-Fir Stands In Maine: The Austin Pond Study, R. Howard Daggett Jan 2003

Long-Term Effects Of Herbicide And Precommercial Thinning Treatments On Species Composition, Stand Structure, And Net Present Value In Spruce-Fir Stands In Maine: The Austin Pond Study, R. Howard Daggett

Electronic Theses and Dissertations

The long-term effect on the development of spruce-fir stands in Maine from combinations of herbicide (Glyphosate, Triclopyr, 2,4-D, 2,4,5-T, MSMA, Picloram, Water, and Control) and precommercial thinning (PCT and no PCT) treatments was examined 22 years after herbicide application and 13 years after PCT. The mean IRR for the herbicide treatments with no thinning was 8.2%. For PCT only the IRR was 6.3%. The mean IRR for plots receiving both herbicide and PCT treatments was 5.8%. Therefore, the rate of return for both herbicide and PCT and combinations of the two treatments would be ...


Vegetation Dynamics And Tree Radial Growth Response In Harvest Gaps, Natural Gaps, And Closed Canopy Conditions In Maine's Acadian Forest, Darci A. Schofield Jan 2003

Vegetation Dynamics And Tree Radial Growth Response In Harvest Gaps, Natural Gaps, And Closed Canopy Conditions In Maine's Acadian Forest, Darci A. Schofield

Electronic Theses and Dissertations

The creation of natural canopy gaps is an important ecological process in the Acadian forest. Designing harvest gaps that emulate natural gap dynamics may be important for maintaining structural and biological diversity, as well as naturally regenerating desired tree species. We used a controlled study to 1) compare vegetation dynamics among and within harvested gaps, natural gaps, and under a closed canopy, and 2) examine the growth response of mature overstory edge trees of harvests gap and saplings inside of gaps as possible methods for dating natural gaps in the Acadian forest. For the vegetation dynamics study (objective I), we ...


Understory Growth Dynamics And Mensuration Techniques In Uneven-Aged, Mixed-Species Northern Conifer Stands, Andrew R. Moores Jan 2003

Understory Growth Dynamics And Mensuration Techniques In Uneven-Aged, Mixed-Species Northern Conifer Stands, Andrew R. Moores

Electronic Theses and Dissertations

Managing uneven-aged, mixed-species stands requires balancing the need for high leaf area allocation in the overstory where it is most efficient versus the need to allow for sufficient growth of younger cohorts in the understory. To help forest managers make informed decisions to maintain this balance, the understory growth dynamics of northern conifer species in stands managed under uneven-aged silvicultural systems were studied. Sapling height growth of Picea rubens Sarg., Abies balsamea (L.) Mill, and Tsuga canadensis (L.) Carr. were modeled as a function of overstory canopy openness (gap fraction) using regression analysis. Research was conducted in four uneven-aged northern ...