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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.
101

Paleoecology of the late-glacial and post-glacial Luedtke Marsh deposit, Waushara County, Wisconsin

Park, Richard Avery. January 1965 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 42-46.
102

Pollen analysis of Iola Bog and paleoecology of the Two Creeks interval

Schweger, Charles Earl, January 1966 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1966. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
103

A record of environmental and climatic change from the West Coast, South Island, New Zealand, using beetle fossils : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Geology in the University of Canterbury /

Burge, Philip I. January 1900 (has links)
Thesis (Ph. D.)--University of Canterbury, 2007. / Typescript (photocopy). "April 2007." Includes bibliographical references (leaves 248-281). Also available via the World Wide Web.
104

Pleistocene mollusca of the Colon deposit, St. Joseph County, Michigan /

Wootton, Clyde Francis. January 1974 (has links)
Thesis (M.S.)--Ohio State University, 1974. / Includes bibliographical references (leaves 50-55). Available online via OhioLINK's ETD Center
105

Systematic, stratigraphic, geographic and paleoecological distribution of the late cretaceous shark genus ptychodus within the Western Interior Seaway /

Hamm, Shawn A., January 2008 (has links)
Thesis (M.S.)--University of Texas at Dallas, 2008. / Includes vita. Includes bibliographical references (leaves 417-434)
106

Paleoecological studies of three Late-Quaternary lacustrine deposits from the Kingston region and some geochemical observations of bottom surface sediments of lakes from Southwestern Quebec

Ouellet, Marcel H January 1973 (has links)
Abstract not available.
107

Prehistoric Human-Environment Interaction in Eastern North America

Munoz, Samuel E January 2010 (has links)
Industrialized human societies both affect and are vulnerable to environmental change, but the dynamics of human-environment relationships during prehistory are less well understood. Using large databases of accumulated paleoecological and archaeological records, this dissertation explores the relationship between prehistoric humans and environmental change in eastern North America. A synthesis of late Quaternary paleoecological and archaeological data from the northeastern United States shows a close temporal correspondence between changes in climate, terrestrial ecosystems, human culture and population numbers. These synchronous changes occurred at 11.6, 8.2, 5.4 and 3.0 thousand years before present, before the adoption of maize agriculture when human groups in eastern North America subsisted by hunting and gathering. Further examination of these datasets in southern Ontario over the last two thousand years found that clearance of forests by prehistoric Native Americans for agricultural fields significantly altered terrestrial ecosystems at a sub-regional scale (102-10 3 m). Together, these results support the hypothesis that prehistoric Native Americans had a greater environmental impact than previously believed, but show that this impact was concentrated around agricultural settlements and was less substantial than that associated with European settlement during the historic period. The methodologies developed in this dissertation provide a means to better understand human-environment relationships in other regions which differ in their environmental and cultural histories.
108

The Atlantic salmon in New England prehistory and history: Social and environmental implications

Carlson, Catherine Carroll 01 January 1992 (has links)
Anadromous fish, and salmon in particular, have frequently been implicated in archaeological models of social complexity for hunter-gatherers. It has been assumed that Atlantic salmon was once an important resource, prior to its extinction in the rivers of southern New England in the eighteenth century, to northeastern prehistoric aboriginal peoples. This perceived importance stems from referents to Atlantic salmon in various historical accounts. These accounts have been interpreted, especially by fisheries biologists involved with salmon restoration programs, and consequently by anthropologists, to indicate a past resource that rivaled present Pacific salmon or Atlantic cod in relative biomass. Archaeological evidence in the form of fish bones recovered from seventy-five sites in the northeastern region, dating from Middle Archaic to Woodland periods (8,000 B.P. to Contact), indicate the virtual absence of Atlantic salmon in the prehistoric period while other types of fish are preserved. This is supported by a complete absence of salmon in the paleontological record for the late glacial/early postglacial period. This research evaluates various cultural and biological possibilities to explain the virtual lack of salmon archaeologically, and the discrepancy between that and the perceived multitudes of Atlantic salmon historically. Factors such as sampling bias, preservation, and lack of aboriginal salmon technology are discounted. Instead, the working hypothesis that salmon did not begin to colonize New England streams in substantial numbers until the historic period, corresponding to a more favorable period of climatic cooling known as the Little Ice Age (A.D. 1550-1800), is presented. Environmental and climatic factors affecting range shifts in salmon and other fish are investigated, as well as genetic relationships between European and American salmon stocks. The presumed abundance of Atlantic salmon based on historical records is also re-examined through a critical source analysis of the social and environmental contexts of the texts, concluding that the great abundance of salmon has been exaggerated both by early and recent writers. The implications for archaeological reconstructions of prehistoric New England aboriginal lifeways without a rich salmon resource are discussed and compared with models of surplus production, storage, and social complexity, for aboriginal peoples inhabiting the Northwest Coast Pacific salmon region. The research concludes that these models are inappropriate for understanding prehistoric cultural developments in New England. In addition, the possibility of a fundamental environmental basis for salmon range expansion and subsequent retraction associated with the beginning and end of the Little Ice Age, as opposed to an anthropogenic basis of pollution and dam building, may have implications for the limited success of biological salmon restoration programs.
109

A modelling-based approach for detecting prehistoric anthropogenic fires in north-central Massachusetts

Kim, John B 01 January 2004 (has links)
The importance of prehistoric anthropogenic fires to the landscape of the Northeast continues to be studied and debated by ecologists. Inferences about prehistoric anthropogenic fires are made using fossil pollen and charcoal evidence from sediment cores taken from ponds and bogs, but the results remain equivocal. I present a modelling-based strategy to locate sediment core sites so that the occurrence of prehistoric anthropogenic fires can be detected in the hilly uplands of north-central Massachusetts. I use a prehistoric human settlement model and ethnographic data about aboriginal fire-setting behavior to predict areas likely to have been burned, and to select suitable ponds for coring. I use a fine-scale, large-area, long-term forest growth model to simulate mid-Holocene vegetation to aid in the interpretation of fossil pollen data at the selected ponds. A list of ponds likely to contain evidence of fire and ponds not likely to contain evidence of fire are provided, along with vegetation patterns likely to be observed at each selected pond and across the study area.
110

The paleoecology of coastal sandplain grasslands on Martha's Vineyard, Massachusetts

Stevens, Andrea 01 January 1996 (has links)
The vegetation history of the island of Martha's Vineyard, Massachusetts during the last millennium was investigated with particular focus on the occurrence and distribution of coastal sandplain grasslands prior to European settlement. The objectives of the research were (1) to examine by paleoecological methods the possibility that grasslands existed on Martha's Vineyard as a "natural" vegetation type before the introduction of European agriculture, (2) to address the effects of land use, fire, soils, and near-coastal location on the occurrence of grasslands across the island during the last 1000 years, and (3) to provide a historical perspective to grassland dynamics that may be relevant to conservation planning and management. To address these research objectives, 12 sediment cores were collected from Martha's Vineyard and analyzed for pollen and charcoal. Nine cores were recovered from the outwash plain, where coastal sandplain grasslands occur today or are known to have occurred historically, and 3 cores were collected from the moraine of the island. Sediments from multiple cores were analyzed to characterize spatial and temporal vegetation changes across the island that may be related to land-use history, fire occurrence, or soil conditions. Vegetation near study sites was sampled to characterize modern grassland and forested communities and to identify environmental gradients responsible for variations in species abundances. Modern vegetation types were also compared to surface pollen assemblages and analogous prehistoric pollen spectra. Results suggest that sandplain grasslands or associated vegetation types occurred on Martha's Vineyard prior to European settlement, at least in localized areas near coastal ponds on the outwash plain, and that these grassland types probably occurred in response to burning by native American Indians. The importance of prehistoric fire on the island is inferred from higher pre- than post-settlement charcoal content in sediments from most study sites. The near-coastal influences along the island's southern shoreline, where early successional communities occur today, may also have favored grassland vegetation types in the past.

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