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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.
1

Movement of fishes in a network of streams and implications for persistence

Albanese, Brett, January 2001 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 2001. / Title from PDF title page (viewed on Apr. 2, 2005). Vita. Includes bibliographical references (p. 107-121).
2

A comparative phylogeographic approach toward defining functional units for the conservation of biodiversity in lotic ecosystems

Wishart, Marcus J. January 2002 (has links)
Thesis (Ph. D.)--Griffith University, 2002. / Title from PDF title page (viewed on May 8, 2005). Includes bibliographical references (p. 136-156).
3

Fish ecomorphology predicting habitat preferences of stream fishes from their body shape /

Chan, Matthew D. January 2001 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 2001. / Title from PDF title page (viewed Apr. 2, 2005). Vita. Includes bibliographical references (p. 127-141).
4

The effects of forest fragmentation on stream invertebrate communities on Banks Peninsula : a thesis submitted for partial fulfilment for the degree of Master of Science in Zoology at the University of Canterbury /

Fraser, Iain A. January 2006 (has links)
Thesis (M. Sc.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (leaves 79-84). Also available vis the World Wide Web.
5

Morphometric variation of bluegill and green sunfish in lentic and lotic systems

Gaston, Kevin A. 21 July 2012 (has links)
Access to abstract restricted until 07/2016. / Department of Biology
6

Streamwater and sediment chemistry of Ohio's Western Allegheny Plateau ecoregion and their relation to aquatic life

Amaning, Kwarteng. January 2006 (has links)
Thesis (M.S.)--Ohio University, August, 2006. / Title from PDF t.p. Includes bibliographical references.
7

Alteration and recovery of a stream macroinvertebrate community exposed to fly ash effluent and an analysis of the causative factors

Specht, Winona L. January 1985 (has links)
Structural and functional changes in the macroinvertebrate community of a fly ash receiving stream were investigated during the final year of fly ash basin operation and for 10 months after fly ash discharges to the stream were terminated. Minimal changes were observed in the benthic community until the basin reached 77% of capacity, at which time the number of macroinvertebrate taxa, density of organisms, diversity, and relative abundance of Ephemeroptera all declined sharply. Ephemeroptera (mayflies) exhibited the greatest sensitivity to the fly ash effluent, while the beetle, Psephenus herricki (Coleoptera) was very resistant to the effects of fly ash. Recovery responses of the macroinvertebrate community were observed one month after fly ash discharges to the stream ended, while full recovery required 10 months. Based on the results of the field study, the toxicity of fly ash constituents (fly ash particulates, pH excursions, and heavy metals) was examined in three species of aquatic insects: Stenonema pudicum (Ephemeroptera), Hydropsyche slossonae (Trichoptera), and Psephenus herricki. Fly ash particulates were not acutely toxic to the three species at concentrations of 4000 mg/l. Stenonema pudicum was consistently the most sensitive species to acidic and alkaline pH extremes and heavy metals (Cd, Cr, Cu, Zn, and a metal mixture), while Psephenus herricki was consistently the most resistant species tested. Alkaline pH extremes and elevated heavy metal concentrations are believed to be responsible for the observed changes in the macroinvertebrate community of the receiving stream during the final two months of basin operation, while elevated heavy metal concentrations were responsible for earlier perturbation of the stream community. / Ph. D.
8

Evaluation of City of Denton Sub-Watershed by Benthic Macroinvertebrate Field Experimental Approach

Mahato, Mahendra 08 1900 (has links)
In this study, two different field experiments were designed to assess the relative influence of urbanization on benthic communities. During spring and summer, four urban and one reference sites from Denton County, Texas were selected for benthic macroinvertebrate evaluation. Statistically significant differences in colonized benthic macroinvertebrate taxa on artificial substrates were observed among the four urban sites and the reference site. Oligochaetes and chironomids were the dominant taxa at all sites. Identification of chironomid larvae at the subfamily and genus level to detect differences between sites had higher statistical power than the evaluation based on total chironomids. At the reference site, Caenis, Cladotanytarsus, Orthocladius, and Ceratopogonidae were the dominant taxa, while the urban sites were dominated by Dero, Physella, Ancylidae, Chironomus, Dicrotendipes, Glyptotendipes, Polypedilum, Pseudochironomus, Stenochironomus, and Tanytarsus. These differences may have been dependent upon differences in hydrologic regime and water quality between sites. Significant differences (ANOVA, p < 0.01) in water quality parameters (alkalinity, hardness, nitrates, phosphates, chlorides, sulfates, calcium, magnesium, potassium, and triazine) were found among water samples collected from the reference and urban sites. During the transfer period, most of the Ephemeroptera and Trichoptera taxa and a few other taxa disappeared from artificial substrates that were colonized at the reference site and then moved to the urban sites. Also, local abundant taxa from the urban site significantly (t test, p < 0.05) increased in number on the transferred artificial substrates. Seasonal differences in colonization patterns were also observed between the spring and summer experimental periods, which indicate that temporal variation is equally important, as is the anthropogenic effect in benthic community evaluation. Field survival and growth experiments using Erpetogomphus designatus larvae were designed to detect differences between evaluated sites. Larvae were collected from the reference site, measured in the laboratory, and exposed at the urban sites for six weeks in using specially designed cages. The exposed larvae demonstrated a higher mortality rate at the urban sites compared to the reference site.

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