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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.
41

Studiën over flora en fauna van het Zuidlaarder Meer. Bijdrage tot de kennis van de biologie der Nederlandsche meren.

Havinga, Berend. January 1919 (has links)
Proefschrift--Groningen. / "Gebruikte litteratuur": p. [183]-188.
42

Inorganic carbon uptake by acidophilic algae /

Balkos, Konstantine Dino. January 2005 (has links)
Thesis (M.Sc.)--York University, 2005. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 88-95). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss &rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR11743
43

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.
44

Assessing interactions between nutrients and toxicity influences of nitrogen and phosphorus on triclosan toxicity to the aquatic macrophyte "lemna gibba" /

Fulton, Barry A. Brooks, Bryan William, January 2009 (has links)
Thesis (M.S.)--Baylor University, 2009. / Includes bibliographical references (p. 65-72).
45

Macrophyte Re-establishment and Deductive GIS Modeling to Identify Planting Locations for Fish Habitat Enhancement Projects

Fleming, Jonathan Paul 01 May 2010 (has links)
Aquatic macrophytes are important components in structuring aquatic communities because they provide physical and biological functions that contribute to the stability of the ecosystem. Macrophytes provide the basis for the aquatic food-web and also provide habitat and refugia for aquatic fauna. In systems that lack macrophytes, anthropogenic re-establishment may be a feasible management approach to improve aquatic ecosystems. Understanding environmental factors that regulate colonization, dispersal, and persistence of aquatic macrophytes is pertinent to re-establishment efforts. The purpose of this study is to test hypotheses regarding success of macrophyte re-establishment efforts in Little Bear Creek Reservoir, Alabama using different macrophyte species, water depths, plant patch size and protection against herbivores at planting sites. In addition, a deductive GIS model is used to predict suitable areas to focus re-establishment efforts. Knowledge generated from hypothesis testing and application of GIS modeling provides novel information and tools for managing aquatic ecosystems.
46

The biology, ecology and management of common reed [Phragmites australis (Cav.) Trin. ex. Steudel]

Cheshier, Joshua Craig 07 August 2010 (has links)
Studies conducted to determine life history and starch allocation of common reed (Phragmites australis), and evaluate haplotype susceptibility to aquatic labeled herbicides. Twelve 0.1 m2 samples were taken from four sites in the Mobile River delta from January 2006 to December 2007. Samples separated into above and belowground biomass dried and weighed. Starch determination used the amylase/amyloglucosidase method. Biomass decreased with decreasing temperature. Aboveground biomass was 2200 and 1302 g m2 in October 2006 and December 2007. Belowground biomass was 1602 and 1610 g m-2 in November 2006 and December 2007. Aboveground starch was highest in December of 2006 and November of 2007. Belowground starch peaked in August of 2006 and September of 2007. RFLP methodologies were used to identify populations of I and M used for herbicide sensitivity screening. No difference detected in the susceptibility of haplotypes. Glyphosate, imazapyr, and triclopyr are effective herbicides for common reed control.
47

Diffusion, boundary layers and the uptake of nutrients by aquatic macrophytes / Jeffrey Julius MacFarlane

MacFarlane, Jeffrey Julius January 1985 (has links)
Offprint of the author's journal article in pocket / Bibliography: leaves 162-193 / x, 193 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Botany, 1986
48

An examination of potential conflict between SAV and hard clam aquaculture in the lower Chesapeake Bay /

Woods, Helen. January 2001 (has links) (PDF)
Thesis (M. Sc.)--College of William and Mary. / Typescript (photocopy). Vita. Includes bibliographical references (leaves 73-87).
49

Culturing Vallisneria americana for Restoration Efforts

Tanski, Erin M. 05 1900 (has links)
Robust Vallisneria americana was cultured for restoration purposes. Preliminary studies, with various iron treatments, were conducted to ascertain the amount of phosphorous release into the water column from sediments. There was a significant difference in the amount of phosphorous released if commercial sediment was used with a low iron amendment or without an iron amendment. The second study consisted of planting V. americana on two different sediment types while supplying half of the plants with additional CO2. Plants grown on pond sediment with additional CO2 had significantly more biomass. In the third study all plants were grown on pond sediment, and half were treated with CO2. All plants that were treated with additional CO2 had significantly more biomass than those that were aerated.
50

Comparative Phyto-uptake Across Distribution Coefficients of Pharmaceutical Compounds and Aquatic Macrophytes: Carbamazepine and Amiodarone Uptake in Lemna Spp

Woodard, Jennifer Kristin 08 1900 (has links)
Few studies have been conducted on the effectiveness of phytoremediation of pharmaceutical compounds, although the persistent and non-acutely toxic nature of many of these compounds in today's water bodies may yield an ideal application for this practice. To quantify the potential effectiveness of plant uptake, kinetic and proportional bioconcentration factors (BCFk, and BCFp, respectively) in nanograms (ng) carbamazepine and amiodarone per gram (g) wet weight plant tissue for Lemna spp. were determined utilizing a 14-day continuous flow-through study. Samples were analyzed using isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) running in positive ion mode. Kinetic BCF was estimated at 0.538, while proportional BCF was estimated at 0.485. Kinetic BCF for the amiodarone study was estimated at 23.033, whereas proportional BCF was estimated at 41.340. Possible contamination of the C18 column and peristaltic pump failure may have impacted uptake results. In light of variability and current lack of research in the field, this work should be considered exploratory rather than conclusive.

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