Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 6 of 6
Full-Text Articles in Forest Sciences
The Long-Term Effects Of A Group-Selection Timber Harvest On The Bird Community Of An Oak-Pine Forest In Maine, Stephen P. Campbell
The Long-Term Effects Of A Group-Selection Timber Harvest On The Bird Community Of An Oak-Pine Forest In Maine, Stephen P. Campbell
Electronic Theses and Dissertations
Bird populations have been monitored at the Holt Research Forest in Arrowsic, Maine since 1983 as part of a long-term forest ecosystem study. In the winter of 1987-1988, 10 ha of the 40-ha study area were subjected to a group-selection timber harvest (i.e., a harvest that creates canopy gaps by removing small groups of trees). I analyzed the first 20 years of these data (5 years of pre-harvest data and 15 years of post-harvest data) for changes in abundance and spatial distribution of birds in response to the harvest. Although species’ responses to the group-selection harvest were idiosyncratic, two general …
The Effects Of Forest Practices On A Maine Amphibian Community, David A. Patrick
The Effects Of Forest Practices On A Maine Amphibian Community, David A. Patrick
Electronic Theses and Dissertations
Changes in forest habitat have been linked to global declines in amphibian populations, but little research has been conducted into the mechanisms causing these declines. This study evaluated the effects of changes in forest habitat on the spatial distribution of a Maine amphibian community, focusing on juvenile wood frogs, Rana sylvatica. Juvenile wood frogs emerging from artificial ponds did not orient towards preferred habitat and a significant number of animals maintained the same directionality documented at the site from which larval individuals were collected. Abundance and habitat use differed among adults of 9 species of amphibians in a replicated …
The Effects Of Clearcutting And Glyphosate Herbicide Use On Parasitic Wasps In Maine Forests, Kristopher J. Abell
The Effects Of Clearcutting And Glyphosate Herbicide Use On Parasitic Wasps In Maine Forests, Kristopher J. Abell
Electronic Theses and Dissertations
Parasitic wasps (parasitoids) play an important role as natural enemies of insects and contribute substantially to world biodiversity (May, 1988), yet they have received relatively little attention outside of agricultural settings. Clearcut harvesting and herbicide (glyphosate) application are frequent and widespread disturbances in Maine forests that drastically alter the local environment. Parasitoids are particularly susceptible to disturbance for several reasons: 1) they are vulnerable to small changes in environmental conditions, 2) they occupy a high trophic level, and 3) many are host specific. However, there may be potential benefits of disturbance such as increased food resources (floral nectaries) and increased …
Effects Of Forest Management On Click Beetle (Coleoptera: Elateridae) Assemblages In The Acadian Forest Of Maine, Shelly L. Thomas
Effects Of Forest Management On Click Beetle (Coleoptera: Elateridae) Assemblages In The Acadian Forest Of Maine, Shelly L. Thomas
Electronic Theses and Dissertations
Click beetle (Coleoptera: Elateridae) assemblages were examined in three experiments in the Acadian forest of Maine. First, I used flight intercept traps to compare Elaterid assemblages in stands that developed after clearcut, shelterwood, and selection harvests. Click beetle richness was highest in stands managed under a selection system and lowest in stands regenerated using the clearcut method. The abundance of click beetle species was lower in stands managed by clearcutting than in stands managed using the shelterwood and selection methods. Hardwood basal area was the best environmental predictor for both species richness and species abundance. Second, I examined whether Elaterid …
Substrate Availability And Regeneration Microsites Of Tolerant Conifers In Mixed-Species Stands In Maine, Jamie K. Weaver
Substrate Availability And Regeneration Microsites Of Tolerant Conifers In Mixed-Species Stands In Maine, Jamie K. Weaver
Electronic Theses and Dissertations
This study investigates regeneration in mixed-species stands in the Acadian Forest of Maine. We examined the effect of silvicultural intensity on available regeneration substrates and how seedling-substrate relationships may be impacted by management activities. Silvicultural treatments studied include two replicates each of 5-year selection, 20-year selection, commercial clearcutting (unregulated harvesting), and three replicates of no management (defined as no harvesting for at least 50 years). We focused on red spruce (Picea rubens Sarg.), eastern hemlock (Tsuga canadensis (L.) Carr.), balsam fir (Abies balsamea L. Mill), and red maple (Acer rubrum L.); all four species are common within the Acadian region. …
Early Life Stage Characteristics Of Six Acadian Conifer Species: Germination And Seedling Development In A Changing Climate, Jason D. Schatz
Early Life Stage Characteristics Of Six Acadian Conifer Species: Germination And Seedling Development In A Changing Climate, Jason D. Schatz
Electronic Theses and Dissertations
Global climate change will drastically alter regional climates. The influence of these changes on the distribution and relative abundance of forest trees is both critically important and subject to substantial uncertainty. It will be particularly important to understand the effects of different climate scenarios on the early life stages of major tree species, because: 1) Early life stage performance and survival strongly influence the abundance of mature trees of a given species, 2) Trees are most sensitive to environmental variation during their early life stages, and 3) Our knowledge of the response of Acadian Forest tree species to environmental variation …