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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Community structure and composition changes of two old-growth forests at Versailles State Park in southeastern Indiana

Behforouz, Kavon Benjamin 04 May 2013 (has links)
In the 1950’s and 1960’s, studies of two old-growth forest stands in Versailles State Park, Laughery Bluff and Dogwood Nature Preserves, were designed and carried out by Potzger to provide the baseline necessary to investigate future trends in these forest communities. In 1968 and 1988, Jackson surveyed these stands again and identified changes in attributes and size classes over that 20-year period. In 2011 and 2012, these sites were re-sampled to document change in species composition and stand structure since 1968. Diameter at breast height (dbh) and species identification were recorded for all stems with dbh ≥ 10 cm. Trees between 1 and 9.9 cm dbh were sampled by counting the number of individuals by species. These data were used to calculate density, dominance, and importance values, as well as to provide full-census data on the overstory size classes at the two sites. Notable findings since the prior studies included the continued increase of Acer saccharum in density and basal area as well as the continued loss of Cornus florida and Fagus grandifolia stems throughout both stands. / Department of Biology
22

Stand dynamics of an old-growth hemlock-hardwood forest in West Virginia

Beane, Nathan R. January 2007 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vii, 55 p. : ill., maps. Includes abstract. Includes bibliographical references (p. 47-50).
23

The forest composition and the pedology of the undisturbed soils in an old-growth virgin beech-maple forest in east-central Indiana

McClain, Mark Stephen 03 June 2011 (has links)
The edaphic and pedologic factors of forest soils and their influence on the naturally occurring climax vegetation in an old-growht forest in east-central Indiana were examined. The northern portion of this woods is a virgin remnant of the presettlement forest that Braun (1950) described as the BeechMaple Forest Region. This remnant is best classified as a sugar maple-American beech-slippery elm association. The undisturbed soils found were the moderately well drained Glynwood soils (Aquic Hapludalfs, fine, illitic, mesic), the somewhat poorly drained Blount soils (Aeric Ochraqualfs, fine, illitic, mesic), the poorly drained Lenawee Variant soils (Typic Haplaquepts, fine, nonacid, mixed,mesic), and the very poorly drained Lenawee (taxajunct) soils (Mollic Haplaquepts, fine-loamy, nonacid, mixed, mesic). The seasonal high water table and internal soil drainage of the soils appear to influence the survival and importance of the dominant tree species. There were 25 tree species sampled.The three most important tree species were sugar maple (Acer saccharum, Marsh.), American beech (Fagus qrandifolia Ehrh.), and slippery elm (Ulmus rubra Muhl.)on the Blount, Glynwood, and Lenawee Variant soils. The fourth most important tree species was silver maple (Acer saccharinum L.) which was restricted to the lowland-depressional forest type (Lindsey and Schmelz, 1970) inclusion represented by the Lenawee (taxajunct) soils. The distribution of tree species occurring on each of the four soils was statistically examined at the 0.05 level of significance. Sugar maple had a significantly higher mean average basal area on the Glynwood soils; American beech had a significantly higher average number of trees on the Blount soils; and slippery elm had a significantly higher proportion of trees on the Glynwood soils.Ball State UniversityMuncie, IN 47306
24

Habitat use by a forest-dwelling bat community in the northern Great Lakes region

Jung, Thomas S. January 2000 (has links)
To examine bat - habitat relationships, ultrasonic detectors were used to sample bat activity among: old-growth white pine (Pinus strobus ), mature white pine, boreal mixedwood, and selectively-cut white pine stands in central Ontario. Within the stands, bats were sampled in the canopy, the understory layer, and within canopy gaps. Forest structure was measured within each of the stands. The activity of bats was compared among forest stand types, within the stands, and in relation to forest structure. Also, maintaining forest wildlife populations requires data on the use of snags (i.e. dead trees). To provide further resolution of the habitat requirements of forest-dwelling bats, radio telemetry and exit counts were used to investigate the roosting ecology of mouse-eared bats (Myotis lucifugus and M. septentrionalis). Characteristics of snags used by mouse-eared bats were compared with randomly located snags and random geographic points, at three spatial scales (focal tree, surrounding forest, and landscape). (Abstract shortened by UMI.)
25

The status of Fagus grandifolia Ehrh. in the midwest : a comparative study of four virgin forests

Clevenger, Brenda K. January 1988 (has links)
This study was undertaken to investigate the status of the american beech as a possible waning species. Contrary to several authors, the results do not suggest a decline in the american beech population. The declines previously indicated probably result from the use of disturbed study sites and incomplete consideration of differences in mortality patterns. The data suggests a stable Beech-Maple forest with neither species experiencing permanent changes in populations. / Department of Biology
26

Growth rates and the definition of old-growth in forested wetlands of the Puget Sound region

Painter, Luke. January 2007 (has links) (PDF)
Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen (viewed on 1/10/2008). Includes bibliographical references (p. 48-51).
27

Determining the cost of old-growth set-asides on the OSU college forest /

Birch, Kevin R. January 1989 (has links)
Thesis (M.S.)--Oregon State University, 1990. / Typescript (photocopy). Includes bibliographical references (leaves 82-85). Also available on the World Wide Web.
28

Legacies of forest management and fire in mixed-pine forest ecosystems of the Seney National Wildlife Refuge, eastern Upper Michigan

Rist, Stephen George. January 2008 (has links)
Thesis (M.S.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 74-79).
29

A geospatial data integration framework for mapping and monitoring tropical landscape diversity in Costa Rica's San Juan-La Selva biological corridor /

Sesnie, Steven E. January 1900 (has links)
Thesis (Ph. D.)--University of Idaho, December 2006. / Major professor: Paul E. Gessler. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.
30

Habitat use by a forest-dwelling bat community in the northern Great Lakes region

Jung, Thomas S. January 2000 (has links)
No description available.

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