Iron in Eutrophic Clear Lake, California: Its Importance for Algal Nitrogen Fixation and Growth

1983 ◽  
Vol 40 (9) ◽  
pp. 1419-1429 ◽  
Author(s):  
Wayne A. Wurtsbaugh ◽  
A. J. Horne
Keyword(s):  
Nitrogen Fixation ◽  
Large Volume ◽  
Carbon Fixation ◽  
Algal Growth ◽  
Clear Lake ◽  
Blue Green Algae ◽  
Green Algal ◽  
Chlorophyll Production ◽  
Low Nitrogen

Clear Lake, California, is warm, shallow, polymictic, and eutrophic. During 1975, levels of dissolved (< 0.45 μm) iron in all three basins of Clear Lake were always low (15–30 μg∙L−1) and decreased to 2 μg∙L−1 during the major bloom of Aphanizomenon flos-aquae. Nitrogen fixation (acetylene reduction) rates of the blue-green algal populations were stimulated as much as 500% above control levels by iron additions in laboratory and in situ large-volume bioassays. Carbon fixation rates and chlorophyll a levels were also significantly stimulated by iron additions, but usually less rapidly and to a lesser extent than N2 fixation. Additions of nitrate stimulated carbon fixation and chlorophyll production but inhibited increases in nitrogen fixation. Phosphate additions either had no effect or produced a mixture of stimulation or depression of all three variables. The bioassays indicate that the growth of blue-green algae and other algae in Clear Lake is usually directly limited by combined nitrogen and occasionally by iron or phosphorus. Low iron levels aggravate the effects of low nitrogen by limiting nitrogen fixation, thus reducing blue-green algal growth.

Effects of Copper on Nitrogen Fixation and Growth of Blue-Green Algae in Natural Plankton Associations

1982 ◽  
Vol 39 (12) ◽  
pp. 1636-1641 ◽  
Author(s):  
Wayne A. Wurtsbaugh ◽  
Alexander J. Horne
Keyword(s):  
Nitrogen Fixation ◽  
Green Algae ◽  
Carbon Fixation ◽  
Copper Toxicity ◽  
Inhibitory Effect ◽  
Clear Lake ◽  
Blue Green Algae ◽  
Limiting Nutrient ◽  
Effect Of Copper ◽  
Pigment Accumulation

Copper toxicity bioassays were conducted on six stages of the spring Aphanizomenon flos-aquae bloom in eutrophic Clear Lake, California. Major variables tested were nitrogen fixation, carbon fixation, pigments, and cell numbers. Inhibition of nitrogen fixation, carbon fixation, and pigment accumulation increased linearly between 10 and 30 μg Cu/L. Higher concentrations produced little additional toxicity. In contrast, there was a stimulatory effect of copper, especially on nitrogen fixation, at the very low level of 2 μg/L. There was no inhibitory effect of copper on nitrogen fixation without a comparable or greater effect on carbon fixation or chlorophyll a. Other algae growing with the Aphanizomenon bloom were not affected by additions of copper up to 20–30 μg Cu/L, but were affected at the 50–100 μg/L level.Key words: algae, algicide, blue-green algae, copper, cyanobacteria, metal, limiting nutrient, nitrogen fixation, photosynthesis, phytoplankton, toxicity

Enhancement of Autotrophic Production by Nutrient Addition in a Coastal Rainforest Stream on Vancouver Island

1978 ◽  
Vol 35 (1) ◽  
pp. 28-34 ◽  
Author(s):  
John G. Stockner ◽  
K. R. S. Shortreed
Keyword(s):  
Algal Biomass ◽  
Algal Growth ◽  
N:P Ratio ◽  
Visual Observation ◽  
Nutrient Addition ◽  
Appreciable Effect ◽  
Blue Green Algae ◽  
Species Succession ◽  
Green Algal ◽  
Enrichment Experiments

In 1976 streamside nutrient-enrichment experiments were conducted using wooden troughs. Tripling of the PO4-P concentration, with or without a similar increase of NO3-N, increased algal biomass on the troughs by 8 times after 35 days. Increasing NO3-N alone had no appreciable effect on algal growth. A sloughing of algal biomass in August 1976 is believed to have been due to the instability of the heavy algal mat on the troughs and to the very poor light conditions that prevailed throughout August. Visual observation indicated that the relatively heavy algal population in Carnation Creek rapidly declined concurrent with the decline in the troughs. The percentage of diatoms in the algal assemblage remained the same in all troughs, and Fragilaria vaucheriae replaced Achnanthes minutissima as dominant on the phosphorus enriched trough. No shift to green or blue-green algal dominated assemblages occurred despite alteration of the N:P ratio. The dynamics of species succession, distribution, and growth, with and without nutrient addition, are discussed. Key words: stream fertilization, autotrophic production, algal succession, N:P ratio, algal distribution, rainforest, algal biomass, diatoms, blue-green algae

scholarly journals Chroococcalean blue green algae from the paddy fields of Satara District, Maharashtra, India

2020 ◽  
Vol 12 (14) ◽  
pp. 16979-16992
Author(s):  
Sharada Jagannath Ghadage ◽  
Vaneeta Chandrashekhar Karande
Keyword(s):  
Green Algae ◽  
Polar Region ◽  
Species Abundance ◽  
Algal Growth ◽  
Wide Distribution ◽  
Paddy Fields ◽  
Study Region ◽  
Blue Green Algae ◽  
Green Algal ◽  
The Family

Blue green algae are the photosynthetic prokaryotes representing a wide distribution in habitat, i.e., temperate, tropical, and polar region.  Paddy fields are the best studied aquatic ecosystems on earth which fulfill all the necessary demands required for blue green algal growth.  Blue green algal role in enhancement of paddy yield has been studied worldwide.  Sustainable utilization of an organism for community use depends on how successfully the ecology of that organism is understood.  Twenty-eight chroococcalean blue green algal taxa were recorded from the study area.  They were taxonomically investigated and found to belong to two families and 11 genera.   The first family Chroococcaceae was the largest family with 10 genera and 26 species while the second family Entophysalidaceae had only one genus and two species.  The genus Gloeocapsa from the family Chroococcaceae exhibited largest species diversity (21.42%), as well as taxa Chlorogloea fritschii of family Entophysalidaceae showed species abundance from the study area.  All heterocystous blue green algal forms are capable of fixation of atmospheric N2.  Many of the non-heterocystous or unicellular blue green algae also have the capacity of N2 fixation.  The taxonomical documentation of chroococcalean blue green algae provide information about such indigenous unicellular blue green algae which will help in the development of niche specific inoculants as biofertilizers for rice fields of the study region.  

Comparison of the Nitrogen-15 Uptake and Acetylene Reduction Methods for Estimating the Rates of Nitrogen Fixation by Freshwater Blue-Green Algae

1980 ◽  
Vol 37 (3) ◽  
pp. 488-493 ◽  
Author(s):  
B. M. Graham ◽  
R. D. Hamilton ◽  
N. E. R. Campbell
Keyword(s):  
Nitrogen Fixation ◽  
Acetylene Reduction ◽  
Experimental Lakes Area ◽  
Method Of Calculation ◽  
Blue Green Algae ◽  
Northwestern Ontario ◽  
Green Algal ◽  
Reduction Methods ◽  
Ratio Determination ◽  
Relationship Of

The relationship of acetylene reduction to nitrogen-15 uptake was investigated using blue-green algal populations in three lakes in the Experimental Lakes Area, northwestern Ontario. Nitrogen fixation rates, as estimated with both techniques, were compared and acetylene to nitrogen ratios determined. Lake ratios ranged from 6.3 to 9.1 moles of acetylene reduced per mole of nitrogen fixed varying from sample to sample and also with the method of calculation. Explanations of the discrepancies between theoretical and empirical ratios are discussed; these include hypotheses of excretion of assimilated nitrogen-15 labeled material and interference from nitrogenase-mediated hydrogen production.Key words: acetylene reduction, nitrogen-15 uptake, nitrogen fixation, C2H2/N2 ratio determination

scholarly journals Simultaneous Quantification of Active Carbon- and Nitrogen-Fixing Communities and Estimation of Fixation Rates Using FluorescenceIn SituHybridization and Flow Cytometry

2014 ◽  
Vol 80 (21) ◽  
pp. 6750-6759 ◽  
Author(s):  
Allison S. McInnes ◽  
Alicia K. Shepard ◽  
Eric J. Raes ◽  
Anya M. Waite ◽  
Antonietta Quigg
Keyword(s):  
Flow Cytometry ◽  
Nitrogen Fixation ◽  
Carbon Fixation ◽  
Biogeochemical Cycles ◽  
Strong Correlations ◽  
Bisphosphate Carboxylase ◽  
Carbon And Nitrogen ◽  
Simultaneous Quantification ◽  
Oceanic Carbon

ABSTRACTUnderstanding the interconnectivity of oceanic carbon and nitrogen cycles, specifically carbon and nitrogen fixation, is essential in elucidating the fate and distribution of carbon in the ocean. Traditional techniques measure either organism abundance or biochemical rates. As such, measurements are performed on separate samples and on different time scales. Here, we developed a method to simultaneously quantify organisms while estimating rates of fixation across time and space for both carbon and nitrogen. Tyramide signal amplification fluorescencein situhybridization (TSA-FISH) of mRNA for functionally specific oligonucleotide probes forrbcL(ribulose-1,5-bisphosphate carboxylase/oxygenase; carbon fixation) andnifH(nitrogenase; nitrogen fixation) was combined with flow cytometry to measure abundance and estimate activity. Cultured samples representing a diversity of phytoplankton (cyanobacteria, coccolithophores, chlorophytes, diatoms, and dinoflagellates), as well as environmental samples from the open ocean (Gulf of Mexico, USA, and southeastern Indian Ocean, Australia) and an estuary (Galveston Bay, Texas, USA), were successfully hybridized. Strong correlations between positively tagged community abundance and14C/15N measurements are presented. We propose that these methods can be used to estimate carbon and nitrogen fixation in environmental communities. The utilization of mRNA TSA-FISH to detect multiple active microbial functions within the same sample will offer increased understanding of important biogeochemical cycles in the ocean.

Speculations on a possible essential function of the gelatinous sheath of blue-green algae

1976 ◽  
Vol 22 (8) ◽  
pp. 1181-1185 ◽  
Author(s):  
Willy Lange
Keyword(s):  
Organic Matter ◽  
Natural Waters ◽  
Algal Cell ◽  
Algal Species ◽  
Algal Growth ◽  
Surrounding Water ◽  
Blue Green Algae ◽  
Green Algal ◽  
Vigorous Growth ◽  
Associated Species

Voluminous and often fluffy sheaths surrounding blue-green algal cells are observed (a) in productive natural waters, (b) in bacteria-containing laboratory cultures growing in inorganic nutrient media with added bacteria-assimilable organic matter, and (c) in axenic cultures in the same inorganic media even without added organic matter. The sheaths of bacteria-associated species in inorganic media without added organic matter are, by comparison, thin, and growth is meager. Repeated observations show that voluminous sheaths and vigorous growth of algal species are associated. It is suggested that formation and retention of a voluminous sheath provide a microenvironment around the algal cell where essential nutrients, present at only submarginal levels in the surrounding water, are concentrated and become readily available to the cell. This increase in nutrient concentration above a critical level, in turn, leads to vigorous algal growth. The voluminous sheath produced by the alga is not attacked by alga-associated bacteria when other assimilable organic matter is available: but in the absence of a more suitable food, the bacteria feed on the less desirable gelatinous sheath, markedly reducing its thickness and causing meager algal growth.

In situ H2 production and utilization by natural populations of N2-fixing blue-green algae

1982 ◽  
Vol 60 (12) ◽  
pp. 2542-2546 ◽  
Author(s):  
Hans W. Paerl
Keyword(s):  
Green Algae ◽  
Acetylene Reduction ◽  
Natural Populations ◽  
H2 Production ◽  
Associated Bacteria ◽  
Parallel Patterns ◽  
Seasonal Trends ◽  
Blue Green Algae ◽  
Green Algal

Contemporaneous in situ acetylene-reduction, 15N2-fixation, and 3H2-exchange assays reveal parallel patterns of N2 fixation and H2 utilization in natural populations of the blue-green algae Anabaena and Aphanizomenon. As spring and summer blooms progress, increasing ratios of acetylene reduction versus 15N2 fixation closely follow elevated rates of cellular H2 utilization. Both acetylene-reduction and H2-utilization rates were largely attributable to blue-green algae as opposed to associated bacteria and other phytoplankton. It is concluded that elevated H2 utilization reflects increased H2 production via nitrogenase. This can be substantiated by monitoring rising acetylene-reduction versus 15N2-fixation ratios during bloom development. Simultaneous deployment of the above techniques provides evidence for (a) in situ H2 production and (b) seasonal trends in rates of H2 production among natural blue-green algal populations.

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