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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.
31

The conservation status of aquatic insects in South-Western Australia /

Sutcliffe, Karen. January 2003 (has links)
Thesis (Ph.D.)--Murdoch University, 2003. / Appendix 1 attached as CD-ROM. Thesis submitted to the Division of Science and Engineering. Bibliography: leaves [156]-173.
32

The impact of invertebrates to four aquatic macrophytes Potamogeton nodosus, P. illinoensis, Vallisneria americana and Nymphaea mexicana /

Nachtrieb, Julie G. Kennedy, James H., January 2008 (has links)
Thesis (M.S.)--University of North Texas, August, 2008. / Title from title page display. Includes bibliographical references.
33

Substrate particle size preference of the caddisfly Macrostemum zebratum (Hagen) (Trichoptera: Hydropsychidae) in small stream riffle

Sottolano, Dane Anthony. January 1990 (has links)
Thesis (M. Ed.)--Kutztown University of Pennsylvania, 1990. / Source: Masters Abstracts International, Volume: 45-06, page: 3051. Typescript. Includes bibliographical references (leaves 42-46).
34

Fate and transport of 17 [beta]-Estradiol in karst aquifers /

Peterson, Eric W. January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 177-191). Also available on the Internet.
35

Fate and transport of 17 [beta]-Estradiol in karst aquifers

Peterson, Eric W. January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 177-191). Also available on the Internet.
36

Changes in the distribution and density of Florida Bay macrophytes: 1995-2004 /

Landry, J. Brooke. January 2005 (has links) (PDF)
System requirements, Adobe Acrobat reader, Microsoft Power Point. / Includes bibliographical references (Leaves: [289]-291)
37

Aquatic leisure & training centre at Stanley

Tse, Kai-lun, Alan. January 1999 (has links)
(M.Arch.)--University of Hong Kong, 1999. / Includes special report entitled : Building systems and materials for assembly construction. Includes bibliographical references. Also available in print.
38

Management of invasive aquatic weeds with emphasis on biological control in Senegal /

Diop, Ousseynou. January 2006 (has links)
Thesis (Ph.D. (Zoology and Entomology)) - Rhodes University, 2007.
39

Abundance and control of nuisance watershield (Brasenia schreberi) populations in Mississippi

Lee, MacKenzie M. 10 May 2024 (has links) (PDF)
Aquatic nuisance plants (ANS), like watershield (Brasenia schreberi), negatively affect water chemistry, ecosystem ecology, and human uses of waterbodies if not properly managed. Understanding ecological predictors as well as efficient control strategies is needed for successful control of ANS. This research assessed 1) potential environmental and ecological predictors of watershield prevalence along with 2) submersed injections of flumioxazin herbicide for watershield control. Twenty-one lakes in the state of Mississippi were surveyed for watershield presence. Watershield prevalence was not correlated to water clarity or plant diversity suggesting these are not drivers of watershield prevalence. A series of mesocosm and field trials were conducted to assess flumioxazin rate reductions for watershield control. In the mesocosm study, 100 ppb flumioxazin injections reduced water shield biomass to >70% 8 weeks after treatment (WAT). This was validated on a field population (>88% reduction) and provides a new control measure for Mississippi resource managers and landowners.
40

Epidemiology of puffy snout syndrome in tuna

Voorhees, Taylor 01 April 2016 (has links)
<p> The domestication of tuna species has proven to be one of the most challenging endeavours in aquaculture. Among the issues yet unresolved is the occurrence of &lsquo;puffy snout syndrome,&rsquo; a condition in which tumour-like growths form on the head. Ultimately, vision and feeding are impaired and long-term afflictions typically result in mortality. Though few mentions of puffy snout exist in the literature, evidence suggests that it is not uncommon among facilities that hold tunas in captivity. The specific aims of this study were to: a) describe pathological features of puffy snout, and b) investigate its etiology through the evaluation of conditions and protocols at facilities rearing/holding tuna. </p><p> To describe pathological features of puffy snout, clinical signs were detailed by observing captive tunas in a land-based holding system, and examination of evidence of infection by parasites, bacteria, and viral agents was conducted on tissues collected from fish with and without puffy snout. Histological examination of tissue from normal and affected fish was also conducted. To investigate etiology, a survey was developed and sent electronically to 28 tuna-holding facilities globally. The survey inquired about the prevalence of puffy snout and the husbandry conditions and protocols employed (e.g., biological characteristics, capture and transport procedures, holding system design and water quality, feeding regime). These data were compared across facilities in an attempt to couple puffy snout prevalence with holding conditions and/or protocols. </p><p> Clinical signs of puffy snout included occlusion of the eyes and mouth, followed by changes to swimming and feeding behaviours. Parasitology, bacteriology, and virology examination all indicated no commonly-found pathological agents were responsible for inducing the condition. Histology showed that puffy snout is largely characterised by the apparent degeneration of muscle tissue with the replacement of a loose collagenous fibrosis and an undetermined fluid filling the interstitial space in tissues anterior to the eye. In dorsal musculature, collagenous growth may occur in the epidermal or hypodermal regions. </p><p> Based on survey data, the capture and transport process and feeding regime were unrelated to development of puffy snout. However, certain biological (e.g., fish size) and holding system (e.g., tank/pen size) parameters showed weak but non-dismissible coupling with puffy snout prevalence. Survey data and additional personal communication with field researchers confirmed that puffy snout in tuna is solely a captivity-related condition.</p>

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