Reference Type: Journal Article Record Number: 113 Author
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Notes: CAN 82:53901 10-1
Microbial Biochemistry Tanners' Counc. Lab.,Univ. Cincinnati,Cincinnati,OH,USA. Journal 0008-4166 written in English. Reference Type: Journal Article Record Number: 86 Author: Reynolds, C. S. Year: 1973 Title: Growth and Buoyancy of Microcystis aeruginosa Kutz. emend. Elenkin in a Shallow Eutrophic Lake Journal: Proceedings of the Royal Society of London. Series B, Biological Sciences Volume: 184 Issue: 1074 Pages: 29-50 Date: Aug. 31 Abstract: The growth of Microcystis aeruginosa in a small, shallow eutrophic lake was studied during three consecutive seasons. The alga was shown to be continuously present in the plankton throughout the period. Exponential increase in the population was confined to a 5 to 8-week period, following the onset of thermal stratification. Populations appeared to originate near the bottom of the euphotic zone. The possession of an effective light-dependent buoyancy control mechanism enabled the alga to maintain station, though progressive deterioration of the photic conditions forced populations to rise and become dissipated within the epilimnion. Buoyancy increased after the cessation of growth; surface blooms often led to the physical removal of a majority of colonies to lee shores. Surviving colonies became generally less buoyant after the lake destratified in autumn. Notes: FLA 00804649
The Royal Society Copyright 1973 The Royal Society URL: http://links.jstor.org/sici?sici=0080-4649%2819730831%29184%3A1074%3C29%3AGABOMA%3E2.0.CO%3B2-N Reference Type: Journal Article Record Number: 84 Author: Moss, Brian Year: 1973 Title: The Influence of Environmental Factors on the Distribution of Freshwater Algae: An Experimental Study: III. Effects of Temperature, Vitamin Requirements and Inorganic Nitrogen Compounds on Growth Journal: The Journal of Ecology Volume: 61 Issue: 1 Pages: 179-192 Date: Mar. Abstract: Growth rates of fifteen species of algae were measured at temperatures between $4^\circ C$ and $36^\circ C$. The maximum growth rates of oligotrophic species tended to be smaller than those of eutrophic species. Temperature optima for growth under the conditions used did not differ between the two groups. Possible adaptive advantages of low growth rates in infertile waters are discussed in relation to theoretical generalizations on the maturity of ecosystems. Some members of both groups required vitamin $B_{12}$ for growth, and most species tested could use either nitrate or ammonium as a nitrogen source. Notes: FLA 00220477
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Copyright 1973 British Ecological Society URL: http://links.jstor.org/sici?sici=0022-0477%28197303%2961%3A1%3C179%3ATIOEFO%3E2.0.CO%3B2-J Reference Type: Journal Article Record Number: 83 Author: Moss, Brian Year: 1973 Title: The Influence of Environmental Factors on the Distribution of Freshwater Algae: An Experimental Study: II. The Role of pH and the Carbon Dioxide-Bicarbonate System Journal: The Journal of Ecology Volume: 61 Issue: 1 Pages: 157-177 Date: Mar. Abstract: Oligotrophic species of algae would not grow at pH values above 8.6-8.85, whilst eutrophic ones grew at pH values above 9, and at considerably higher bicarbonate levels than did the former. The results are interpreted in terms of the available free $CO_2$ at various combinations of pH and bicarbonate. Oligotrophic species are probably confined to free $CO_2$ as an inorganic carbon source for photosynthesis, and may be unable to absorb it below certain concentrations (at least 0.011 mM). Eutrophic species may either use bicarbonate directly or may be able to use free $CO_2$ at very low concentrations. Field observations support the hypothesis that the availability of free $CO_2$ prevents growth of oligotrophic species in hard waters. Notes: FLA 00220477
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Copyright 1973 British Ecological Society URL: http://links.jstor.org/sici?sici=0022-0477%28197303%2961%3A1%3C157%3ATIOEFO%3E2.0.CO%3B2-R Reference Type: Journal Article Record Number: 271 Author: Khan, K. R.; Schumacher, G. J. Year: 1973 Title: The induction of akinetes and their germination in Gloeotrichia echinulata (J.E. Smith) Right Journal: Journal of Phycology [J. Phycol.] Volume: 9 Issue: Suppl. Pages: [np] Accession Number: 5197924 Keywords: Freshwater Q1 01224 Reproduction and development Abstract: Plankton colonies of Gloeotrichia echinulata collected from Conesus Lake, NY, during the summer of 1972 did not show any akinetes. The surface water temperature of the lake ranged from 19 degree C in the early morning hours to 27 degree C in the later afternoon. When these colonies were cultured in the laboratory at 21 degree C and 15 degree C for similar to 3 weeks, akinetes developed. The order of frequency of induction of akinetes decreased with decreased temperature. Akinetes from the induced colonies were isolated for the purpose of studying the frequency of germination by homogenation followed by centrifugation. When the isolated akinetes were placed in fresh medium, the frequency of germination increased with time up to 2 weeks. The germination could not be followed into the 3rd weeks as the germlings started developing and occasionally releasing akinetes of their own. There seems to be 2 modes of releasing germlings from the akinetes. Notes: 1973. 0022-3646 Records keyed from 1973 ASFA printed journals English
Journal Article Author Address: State Univ. New York Binghampton, NY USA Reference Type: Journal Article Record Number: 272 Author: Findley, D. L.; Findley, D. I.; Stein, J. R. Year: 1973 Title: Surface nitrogen and plankton in Skaha Lake, British Columbia (Canada) Journal: Freshwater Biology Volume: 3 Issue: 2 Pages: 111-122 Alternate Journal: Freshwat. Biol. Accession Number: 5195164 Keywords: Freshwater Q1 01381 General Abstract: This study (1970-1971) of an oligotrophic lake subject to cultural enrichment indicates the presence of complex interrelations between plankton and N sub(2) levels in surface waters. Generally inorganic N sub(2) was high in the winter (0.4-0.5ppm) and low in summer (<0.1 ppm). However, in late July and Aug a large increase in N sub(2) (1.5 ppm) was recorded. This correlated with the Gloeotrichia echinulata J.E. Smith ex P. Richt, bloom (Cyanophyceae) and the increase in N sub(2) fixation, or nitrogenase activity (measured as acetylene reduction). It was calculated that the cyanophyte bloom could have contributed a minimum of 2350 kg N sub(2) to the lake in Aug 1970 which is approximately 62% of the nitrate-N sub(2) occurring at any time. Notes: 1973. 0046-5070 Records keyed from 1973 ASFA printed journals English
Journal Article Author Address: Dep. Bot., Univ. British Columbia Vancouver 8 Canada Reference Type: Journal Article Record Number: 85 Author: Daft, M. J.; Stewart, W. D. P. Year: 1973 Title: Light and Electron Microscope Observations on Algal Lysis by Bacterium CP-I Journal: New Phytologist Volume: 72 Issue: 4 Pages: 799-808 Date: Jul. Abstract: Bacterium CP-1 isolated from Scottish waters is an aerobic prokaryote with a high guanine:cytosine ratio (68%), which causes lysis of a variety of blue-green algae. When suspensions of algae and bacteria are mixed the bacteria can be seen to glide towards the algae where they become attached end-on round the algal cells. There is evidence that the bacteria produce substances at the point of contact with the algae which are necessary for algal lysis to occur. Lysis of vegetative cells may occur within 30 minutes of the bacteria becoming attached. Heterocysts do not lyse in this way although their intracellular contents may eventually degenerate. When vegetative cells rupture, the protoplasmic contents, including gas vacuoles when present, are released and empty-looking 'ghosts' which retain the original cell shape may remain for a time although these too eventually break down. There is some evidence that the mode of filament lysis may be random, intercalary or terminal. At the ultrastructural level the initial effect of CP-1 is to cause lysis of the L$_2$ layer of the algal cell wall and this effect is similar to that obtained using lysozyme. This is followed by rupture or disintegration of the other cell wall layers, and 'scroll'-like structures, either of coiled up cell wall material (Microcystis) or of the plasmalemma (Nostoc) may be found scattered throughout the preparations of lysed cells. In fully lysed cells there is a loss of polyphosphate bodies, structured granules, gas vacuoles, and most other cellular inclusions. Released gas vesicles can be collected from the surface of the solution of lysed cells, and there is evidence that these vesicles may fracture easily near the conical ends. In fully lysed cells, the thylakoid membranes remain, often with wide lumens between. This thylakoidal system is contorted and branched, ramifies through the cell and shows constrictions of the membrane system at intervals. Continuity between the plasmalemma and the thylakoidal system can be seen clearly. Lipid droplets which are resistant to CP-1 treatment are found in the lumen of the thylakoidal system. Heterocysts are not as markedly affected by CP-1 as are vegetative cells, but eventually heterocyst disorganization also occurs. The use of CP-1 provides a technique for preparing material for the study of algal membranes and gas vesicles. Notes: FLA 0028646x
Cambridge University Press latex
Copyright 1973 New Phytologist Trust URL: http://links.jstor.org/sici?sici=0028-646X%28197307%2972%3A4%3C799%3ALAEMOO%3E2.0.CO%3B2-C Reference Type: Journal Article Record Number: 273 Author: Tiwari, G. L. Year: 1972 Title: A study of the blue-green algae from paddy field soils of India Journal: Hydrobiologia Volume: 39 Issue: 3 Pages: 335-350 Accession Number: 5503853 Keywords: Freshwater Q2 02101 General works Abstract: The blue-green algal flora was screened in Nov 1964 at 9 sites in the following states; Madhya, Pradesh, Maharashtra, Mysore and Madras. 132 forms were recorded, including the following which are new: Aphanocapsa stagnina (SprEng.) A.Braun f.n., Oscillatoria okeni Ag.ex Gomont f.n., O.proboscidea Gomont f.n., Phormidium mucosum var arvense Rao f.n., Lyngbya spiralis Geitler f.crassivaginata f.n., L.spirulinoides Gomont f.crassa f.n., Microcoleus vaginatus (Vaucher) Gomont f.n., Cylindrospermum majus Kuetz.ex Born.et Flah.f.n., C.licheniforme Kuetz.ex Born et Flah.f.n., Anabaena iyengarii var attenuata f.n., A.cylindrica var marchica Lemm.f.n., Scytonematopsis ghazipurensis Pandey et Mitra f.n., Gloeotrichia pilgeri Schmidle f.n., Hapalosiphon arboreus West et West f.n., Phormidium tenue (Menegh.) Gomont var minor var.n., Anabaena cylindrica Lemm.fertilissima var.n., Calothrix javanica De Wilde var fertilissima var.n., Chroococcidiopsis mysorensis sp.n., Anabaena indica sp.n., Hapalosiphon fertilissima sp.n., Symphyonemopsis katniensis gen.et sp.n. Each site yielded an average of 23.8 spp. Spp distribution is compared between material growing naturally and that obtained from soil samples cultured in the laboratory. 37% occurred naturally, 48.4% occurred only in culture and 13.6% were common to both. General spp distribution is discussed with reference to the work of previous authors. It is shown that heterocystous spp are more frequent than non-heterocystous spp under natural but not under culture conditions. Notes: 1972. 0018-8158 24 refs. Records keyed from 1972 ASFA printed journals. English
Journal Article Author Address: Bot. Dep., Allahabad Univ., Allahabad 2, India Reference Type: Journal Article Record Number: 274 Author: Singh, R. N.; Tiwari, D. N.; Singh, V. P. Year: 1972 Title: Genetic basis of cellular differentiation in blue-green algae Journal: Taxon. Biol. Blue-Green Algae, Pap. Int. Symp., 1st Pages: 27-37 Accession Number: AN 1975:440088 Keywords: Algae (blue-green, differentiation by, nitrogen source effect on) bluegreen alga differentiation nitrogen Abstract: Differentiation of heterocysts, hormongonia, and spores in blue-green algae is genetically controlled. However, their phenotypic expression is dependent on growth conditions. Heterocyst differentiation is suppressed in the presence of combined sources of N, i.e., nitrate and ammonium but it is induced in the presence of N gas. There is heterocyst differentiation in the very 1st division during spore germination in Nostoc linckia, in a N-free medium. But, differentiation of heterocyst is suppressed in the presence of nitrate and ammonium to the extent of the function of their concn. Heterocyst frequency increases 3-4-fold in blended cultures grown in N-free medium, whereas it decreases in the presence of nitrate and ammonium. Only a few colonies show delayed heterocyst differentiation in N-free medium after uv irradn. of N. linckia and Anabaena variabilis. Mutants with high frequency of heterocysts were also isolated after uv irradn. Incorporation of acriflavin in agar medium free of combined N temporarily inhibited heterocyst differentiation in a mutant of A. variabilis. Frequent heterocyst germination ?83% was obtained in a nonsporulating clone of Gloeotrichia ghosei, in presence of ammoniacal N and 24% in a mutant of N. linckia, in N-free medium. Nitrate enhances early and synchronous sporulation whereas ammonium delays and reduces the frequency of spores as compared to N-free medium, in N. linckia. The acriflavine-resistant mutant of A. variabilis lacks hormogone prodn. and nonsporulating as well as hormogone-producing mutants of N. linckia have been isolated after uv irradn., showing chains of heterocysts. [on SciFinder (R)] Notes: CAN 83:40088 10-4
Microbial Biochemistry Dep. Bot.,Banaras Hindu Univ.,Banaras,India. Conference written in English. 7727-37-9 Role: BIOL (Biological study) (blue-green alga differentiation in response to source of)
00220477
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Copyright 1972 British Ecological Society URL: http://links.jstor.org/sici?sici=0022-0477%28197211%2960%3A3%3C917%3ATIOEFO%3E2.0.CO%3B2-1 Reference Type: Journal Article Record Number: 32 Author: Kehde, Peter M.; Wilhm, Jerry L. Year: 1972 Title: The Effects of Grazing by Snails on Community Structure of Periphyton in Laboratory Streams Journal: American Midland Naturalist Volume: 87 Issue: 1 Pages: 8-24 Date: Jan. Abstract: The effects of grazing by snails on community structure of periphyton were studied in laboratory streams. The levels of grazing studied caused slight reduction in standing crop, significant increase in chlorophyll a concentration, reduction in pigment diversity and no effect on species diversity. Grazing did not affect instantaneous rates of accumulation of oven-dry weight, ash-free weight, or ash-free percentage of oven-dry weight. Pigment diversity and species diversity were positively correlated. Oven-dry weight per unit chlorophyll a was reduced by grazing, but ash-free weight per unit chlorophyll a was not affected. Grazing had no effect on the percentage of chlorophyll a in ash-free weight. Notes: FLA 00030031
University of Notre Dame Copyright 1972 The University of Notre Dame URL: http://links.jstor.org/sici?sici=0003-0031%28197201%2987%3A1%3C8%3ATEOGBS%3E2.0.CO%3B2-L Reference Type: Journal Article Record Number: 7 Author: Confer, John L. Year: 1972 Title: Interrelations among Plankton, Attached Algae, and the Phosphorus Cycle in Artificial Open Systems Journal: Ecological Monographs Volume: 42 Issue: 1 Pages: 1-23 Date: Winter Abstract: The circulation of phosphorus in 200-liter aquaria, continuously supplied with tap water, was analyzed by means of analytical and tracer methods. This open-system design ultimately resulted in a steady-state system whereby the influx of phosphorus to various biological compartments was equaled by a corresponding outflow. This model of phosphorus circulation is believed to apply to small lakes with extensive littoral vegetation during summer stratification, but contrasts with models proposed from other tracer studies on such lakes. The other models are considered to be feasible, but unlikely and based on incorrect analyses of data. Previous estimates of the rate of phosphorus circulation based on tracer analyses are reanalyzed and appear to be of the correct magnitude. The 200-liter system developed two communities of attached and planktonic organisms, with the former rapidly removing a large percentage of the phosphorus from the latter. With this removal any direct relationship between the phosphorus concentration of the open water and the influx concentration was obscured. A major means by which phosphorus was removed from the open water was shown to be trapping of particles by the community associated with the sides of the aquaria. The rate of such removal varied widely, depending on the extent of @'littoral@' growth and the nature of the particle. These results suggest that a multicompartment analysis of nutrient circulation is significantly more realistic than a simplistic assumption of homogeneity. Considering succession to be the total change in physical and biological conditions over prolonged time, this open-system design developed from a one-community, few-species system into a two-community, several-species system. The rate of nutrient circulation greatly increased with time and developed into a steady state, not an equilibrium system which depended on a continual phosphorus influx to maintain the concentrations and circulation rates. Notes: FLA 00129615
The Duke University Press EN Copyright 1972 The Ecological Society of America URL: http://links.jstor.org/sici?sici=0012-9615%28197224%2942%3A1%3C1%3AIAPAAA%3E2.0.CO%3B2-Q Reference Type: Journal Article Record Number: 275 Author: Ahmad, M. R. Year: 1972 Title: Algae of Allen Forest Lake, Kanpur, India. I. Cyanophyceae Journal: Nova hedwigia. Lehre Volume: 23 Issue: 1 Pages: 125-129 Alternate Journal: Nova Hedwigia Accession Number: 5196205 Keywords: Freshwater Q1 01383 Biogeography and biogeographic regions Abstract: 34 species of Cyanophyceae collected during 1963-1965 from Allen Forest lake, Kanpur, India are described. The following general of Cyanophyceae were represented (the numbers in parenthesis indicate the number of species of each genus). Gloeothece (1), Aphanothece (2), Coelopshaerium (2), Gomphosphaeria (1), Merismopedia (2), Stichosiphon (1), Oscillatoria (9), Phormidium (4), Lyngbya (3), Cylindrospermum (1), Nostoc (1), Anabaena (1), Aulosira (1), Tolypothrix (1), Microchaete (1), Calothrix (2), Gloeotrichia (1). Notes: 1972. 0029-5035 Records keyed from 1973 ASFA printed journals English
Journal Article Author Address: Algol. Lab., Natl. Bot. Gardens Lucknow India Reference Type: Journal Article Record Number: 8 Author: Stewart, W. D. P.; Mague, T.; Fitzgerald, G. P.; Burris, R. H. Year: 1971 Title: Nitrogenase Activity in Wisconsin Lakes of Differing Degrees of Eutrophication Journal: New Phytologist Volume: 70 Issue: 3 Pages: 497-509 Date: May Abstract: Nitrogen fixation in various Wisconsin lakes was compared using the C$_2$H$_2$ reduction technique. Rates of C$_2$H$_2$ reduction were unaffected by N$_2$ when sufficient C$_2$H$_2$ was added to the gas phase. Thus in field studies the natural gas phase need not be removed before the addition of C$_2$H$_2$. C$_2$H$_2$ was reduced rapidly in eutrophic waters (Little Arbor Vitae Lake, Lake Mendota and southern Green Bay) but more slowly in oligotrophic waters (Crystal Lake, Trout Lake, Lake Mary and northern Green Bay). C$_2$H$_2$ reduction was greatest in the surface waters, was largely light-dependent and showed a marked diurnal variation. There was also significant variation with area and with time, and in general acetylene reduction was detected only when heterocystous algae were present. The rate of nitrogen fixation in Lake Mendota, calculated on the basis of weekly measurements taken during most of the ice-free season, was approximately 2.4 kg/ha/year. Directory: chemistry chemistry -> Summer 2015 Research Opportunities for Chemistry & Biochemistry Undergraduates chemistry -> Application for Summer Undergraduate Research Program nsf research Experiences for Undergraduates (reu) – 2015 Please Print Clearly or Type chemistry -> Application for Summer Undergraduate Research Program nsf research Experiences for Undergraduates (reu) – 2016 Please Print Clearly or Type chemistry -> Summer 2014 Research Opportunities for Chemistry & Biochemistry Undergraduates chemistry -> Summer 2016 Research Opportunities for Chemistry & Biochemistry Undergraduates chemistry -> Cloud Point Extraction Methodology for Separation and Microamounts Determination of Lead chemistry -> Spring Hill College List of Nearby Restaurant Options Atlanta Bread Company chemistry -> Where the heck is Fernando de Noronha? chemistry -> Topics 6 & 16: Kinetics 1 Collision theory and rates of reaction Download 1.4 Mb. Share with your friends:
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