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The ecology of algal assemblages across a gradient of acid mine drainage stress on the West Coast, South Island, New Zealand : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Biology in the University of Canterbury /Bray, Jonathan Peter. January 1900 (has links)
Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). "June 2007." Includes bibliographical references (leaves 83-94). Also available via the World Wide Web.
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Structural and functional aspects of epiphytic and benthic algae in the acidified Lake Gårdsjon̈, SwedenLazarek, Stanislaw. January 1983 (has links)
Thesis (doctoral)--Lunds universitet, 1983. / Includes bibliographical references.
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A study to measure pollution effects on the antithermal maintenance and diversity index of stream periphyton of Little Cedar Creek and to illustrate the succession of the diatom fractionKareyva, Albert Joseph. January 1985 (has links)
Thesis (M.S.)--Kutztown University. / Source: Masters Abstracts International, Volume: 45-06, page: 3039. Typescript. Abstract precedes thesis as preliminary leaves [1-4]. Includes bibliographical references (leaves [51-52]).
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Analysis of patterns in algal community structure in the North Alouette River watershed, British ColumbiaWehr, John David January 1979 (has links)
Patterns in algal community structure and physiochemical characteristics
of streams and one impounded subalpine lake in the mountainous North
Alouette River watershed, British Columbia, were described for one year
from June 1977 to June 1978. In this period, 266 algal taxa were recognized,
of which 59 were previously unrecorded in the province. The streams were
characterized by an epilithic flora consisting predominantly of. unbranched
Chlorophyta and secondarily by both branched and unbranched Cyanophyta.
Bacillariophyta (diatoms) were species rich (over 100 taxa), but were at all
times relatively unimportant in the streams, although frequently dominant
in the epipelon of Jacob's Lake. Species of Rhodophyta were locally
abundant only in shaded habitats. Many epilithic and epiphytic species
were "host" specific in their substrate preferences.
Stream water in the North Alouette was slightly acid (pH 6-7) and
nutrient poor, the relative order of anions being S0₄²⁻ > SiO₂ > CI⁻ >N0₃⁻ >
PO₄³⁻ and cations Ca²⁺ = Na⁺ > Mg²⁺ > K > NH₄⁺ > Fe²⁺/³⁺, Mn²⁺, and Al³⁺
were not detected in the dissolved fraction. Other variables indicated this to be a rapidly flowing (often > 1m sec⁻¹), cool (2-18°C seasonally), poorly buffered (HCO₃⁻ = .06-.40 meq 1⁻¹), and highly heterogeneous environment.
Stations along the stream gradient differed in conditions of slope, current velocity, degree of shading, and substrate size, but not in temperature, pH, and possibly nutrient chemistry.
A principle coordinates analysis (P-Co-A) of seasonal succession at one station (Station 1) revealed a cyclic pattern characterized by sequences of gradual and abrupt changes in species composition. Temporal extinction of dominant species did not occur, as has been shown for phytoplankton
populations in lakes. Current velocity, depth, temperature, CI⁻, and SO₄²⁻ were significantly correlated (P<0.05) with most of the seasonal variability in the algal community. A smaller amount of the seasonal change was correlated with the flux of dissolved cations. P-Co-A also exposed similarities between six stations within the watershed which were not consistent seasonally, and gave no evidence of distinct zones. Distribution of algal species within Station 1 in May shown by cluster analysis, occurred roughly in two groups, corresponding to near-shore and midstream habitats.
The general heterogeneity of algal distribution and the occasional disturbance by flooding gave rise to periodic peaks in diversity, although many common species never became abundant. Hence, no clear-cut relation was realized between the physiochemical environment and species diversity. Hypotheses are generated, suggesting that (1) distribution of red algae was shade limited; (2) diatom dominance was limited by nutrient chemistry; (3) the even pattern of seasonal succession was interrupted by periodic events, such as nutrient pulses and floods; and (4) a large degree of species coexistence was provided by these periodic disturbances. / Science, Faculty of / Botany, Department of / Graduate
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Assessment of anti-neoplastic activity in cancerous and non-cancerous cells using nuclear growth indicatorsWilliams, James Michael 01 January 1997 (has links)
No description available.
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A study of synthesis and organization of the secondary cell wall in NitellaYousef, Martin Christopher 01 January 1992 (has links)
Mechanical support is a required function of most biological materials. Skeletal helicoids are a structural motif often used in the construction of plant cell walls and arthropod exoskeletons. Nitella axillaris, a giant-celled freshwater alga has many characteristics which make it an ideal subject for helicoidal analysis. Earlier research had shown that the cell wall of mature Nitella internodes exhibit helicoidal layers. However, no previous work had concentrated on studying the relationship between the presence of helicoids and internodal age. The work presented here examines the relationships among growth rate, cell age, cell length, and presence of helicoidal layers. Internodes were categorized according to age, from their position along the shoot. In addition, by monitoring cell growth, the cultures were classified into three groups, slow, medium and fast. Cross sections of the various cells were examined for the presence of helicoidal layers. Once the presence of helicoidal layers was established, oblique, longitudinal and tangential sections were used to further study helicoidal structure. We showed that the transition state between the presence and lack of helicoidal layers is between cells III and IV. The timing of this transition was not exact but more or less coincided with the cessation of cell elongation. Also, no apparent correlation was found between the timing of helicoid deposition and growth rate for cells of equivalent age (internode number}.
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Palaeoenvironment of Late Neogene Lacustrine Sediments at the Gray Fossil Site, Tennessee, USAWorobiec, Elzbieta, Liu, Yu Sheng Christopher, Zavada, Michael S. 31 July 2013 (has links)
A new palaeopalynological investigation was conducted on 15 samples from four test-pits at the Gray Fossil Site (Bear Pit, Elephant Pit, Test Pit 2-2010, and Rhino Pit). In total, 50 morpho-species of miospores (including five species of spores, eight species of gymnosperm pollen, and 37 species of angiosperm pollen) and 18 morpho-species of freshwater algal micro-remains were identified. One new morphological species, related to zygospores of the Zygnemataceae, Stigmozygodites grayensis sp. nov., is proposed. The assemblage of fossil algae recovered provides insights into the palaeoenvironmental conditions of the uppermost (125 cm) part of the Gray Fossil Site sedimentary cover, deposited after the formation of a number of sinkholes, and the fill of the palaeosinkholes. Most of the algae identified prefer meso-to eutrophic conditions and are characteristic of stagnant to slowly flowing shallow fresh water. Therefore, the lacustrine fossiliferous sediments at the Gray Fossil Site represent pond deposits. The palaeopalynological analysis revealed differences in the composition of the miospore and algal assemblages of the pits studied, suggesting that the Test Pit 2-2010, Bear, and Elephant pits are similar and may have been formed in the same pond, while the presence of a higher percentage of algae in the Rhino Pit may indicate sedimentation in a separate water body.
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Palaeoenvironment of Late Neogene Lacustrine Sediments at the Gray Fossil Site, Tennessee, USAWorobiec, Elzbieta, Liu, Yu Sheng Christopher, Zavada, Michael S. 31 July 2013 (has links)
A new palaeopalynological investigation was conducted on 15 samples from four test-pits at the Gray Fossil Site (Bear Pit, Elephant Pit, Test Pit 2-2010, and Rhino Pit). In total, 50 morpho-species of miospores (including five species of spores, eight species of gymnosperm pollen, and 37 species of angiosperm pollen) and 18 morpho-species of freshwater algal micro-remains were identified. One new morphological species, related to zygospores of the Zygnemataceae, Stigmozygodites grayensis sp. nov., is proposed. The assemblage of fossil algae recovered provides insights into the palaeoenvironmental conditions of the uppermost (125 cm) part of the Gray Fossil Site sedimentary cover, deposited after the formation of a number of sinkholes, and the fill of the palaeosinkholes. Most of the algae identified prefer meso-to eutrophic conditions and are characteristic of stagnant to slowly flowing shallow fresh water. Therefore, the lacustrine fossiliferous sediments at the Gray Fossil Site represent pond deposits. The palaeopalynological analysis revealed differences in the composition of the miospore and algal assemblages of the pits studied, suggesting that the Test Pit 2-2010, Bear, and Elephant pits are similar and may have been formed in the same pond, while the presence of a higher percentage of algae in the Rhino Pit may indicate sedimentation in a separate water body.
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Uptake and effects of Kepone on growth, respiration and photosynthesis of Chlorella sorokiniana and Chlorococcum hypnosporumYoung, Gary Robert January 1978 (has links)
Kepone®, the registered trade name for decachlorooctahydro-1,3, 4-metheno-2H-cyclobuta cd pentalen-2-one, inhibited growth and reduced rates of photosynthesis and respiration of Chlorella sorokiniana Shihira and Kraus and Chlorocbccum hypnosporum Starr. The insecticide reduced rates of respiration more than photosynthesis. Uptake of ¹⁴C-Kepone by the algae was proportional to cellular concentration. A net efflux of Kepone was exhibited by Chlorella cells after 30 minutes of incubation, whereas, equilibrium occurred within 15 minutes of incubation for Chlorococcum. Desorption of Kepone was evident when both algal species were removed from Kepone treated solutions and incubated in untreated nutrient solutions. / Master of Science
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An Investigation of Algae and Common Tastes and Odors in Fresh WaterHarmon, John C. 06 1900 (has links)
The purpose of this investigation was to isolate and grow algae common to the southwest in unialgal culture; to either sustain or grow one of the principal bloom-causing organisms, with emphasis on Microcystis aeruginosa; to isolate and culture actinomycetes from the same waters from which the algae were obtained; and to inoculate these algae with actinomycetes and determine their effects through development and deterioration.
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