Bacterial Productivity in Forested and Open Streams in Southern Ontario

1992 ◽  
Vol 49 (11) ◽  
pp. 2412-2422 ◽  
Author(s):  
J. J. Hudson ◽  
J. C. Roff ◽  
B. K. Burnison
Keyword(s):  
Water Column ◽  
Bacterial Production ◽  
Time Course ◽  
Net Primary Production ◽  
Stream Water ◽  
Bacterial Biomass ◽  
Bacterial Productivity ◽  
Southern Ontario ◽  
Bacterial Dna ◽  
Heterotrophic Production

Bacterial abundance, biomass, and heterotrophic production were measured in the water, sediment, and epilithon of forested and open streams in southern Ontario in summer 1988. Relationships of environmental variables to production were examined. The time course of nucleoside incorporation, recovery efficiency of bacterial DNA, isotope dilution, and disturbance artifacts were examined to compare bacterial production rates and to determine the appropriateness of the rate of [3H]thymidine incorporation into bacterial DNA as an estimate of bacterial production in these habitats. Water column bacterial biomass (12–97 μg C∙L−1) and heterotrophic production (0.21–67 μg C∙L−1∙h−1) were greater in open streams than in forested streams. Differences between open and forested stream sediment bacterial biomass (0.30–1.1 g C∙m−2) and heterotrophic production (18–140 mg C∙m−2∙h−1) were not as pronounced as they were in the water column. A methodological disturbance artifact may have introduced a minor bias in sediment production measurements. Epilithic bacterial biomass was 35–150 mg C∙m−2, and heterotroph production was 1.3–51 mg C∙m−2∙h−1, significantly greater (P < 0.05) in open streams than in forested streams. Epilithic production and stream water temperature were positively correlated (P < 0.05). Heterotrophic bacterial production exceeded net primary production in forested streams, but not in open streams.

Heterotrophic Bacterial Production and Its Dependence on Autotrophic Production in a Hypertrophic African Reservoir

1990 ◽  
Vol 47 (5) ◽  
pp. 1027-1037 ◽  
Author(s):  
Richard D. Robarts ◽  
Richard J. Wicks
Keyword(s):  
South Africa ◽  
Primary Production ◽  
Water Temperature ◽  
Water Column ◽  
Bacterial Growth ◽  
Bacterial Production ◽  
Doubling Time ◽  
Limiting Factor ◽  
Close Coupling ◽  
Bacterial Dna

The incorporation of [methyl-3H]thymidine (TdR) into bacterial DNA in Hartbeespoort Dam, South Africa was measured over 16 mo and at nine depths. Bacterial numbers at the surface ranged between 2.45 and 32.20 × 106 cells∙mL−1[Formula: see text] while bacterial production varied between 1.0 and 251 pmol TdR∙L−1∙h−1 (0.01 to 1.9 mg C∙m−3∙h−1). At the bottom, production ranged between 0 and 26.7 pmol TdR∙L−1∙h−1 (0–0.2 mg C∙m−3∙h−1). The fastest bacterial doubling time was 59 h. At the surface, bacterial production was dominantly correlated to chlorophyll a (6.6–6530 mg∙m−3) and phaeopigments (0.9–378 mg∙m−3) (r = 0.81) followed by primary production (26.6–8886 mg C∙m−3∙h−1) (r = 0.77) (n = 30–34, p < 0.001). However, below 5 m, water temperature and bacterial numbers were the dominant correlates. Bacterial production for the water column averaged 2% of daily, areal primary production. The data demonstrated a close coupling between autotrophic production and heterotrophic bacterial production. However, the low bacterial production compared with primary production, together with the small size of the bacteria (usually 0.09–0.25 μm width), suggest substrate supply was a major limiting factor of bacterial growth.

scholarly journals Bacterial production in Guanabara Bay (Rio de Janeiro, Brazil) evaluated by ³H-leucine incorporation

2000 ◽  
Vol 43 (5) ◽  
pp. 493-500 ◽  
Author(s):  
Alessandra M. Gonzalez ◽  
Rodolfo Paranhos ◽  
Luciana Andrade ◽  
Jean L. Valentin
Keyword(s):  
Bacterial Production ◽  
Bacterial Biomass ◽  
Biogeochemical Cycles ◽  
Leucine Incorporation ◽  
Guanabara Bay ◽  
Bacterial Productivity ◽  
Isotope Concentration ◽  
Main Circulation ◽  
The Relationship ◽  
The Ideal

The aim of this work was to evaluate the necessary ³H-leucine concentration to estimate bacterial production in Guanabara Bay through saturation curves. A second aim was to collect preliminary data of bacterial production in two distinct sites corresponding to different water qualities: Urca inlet and Governador Island. Saturation curves were made with water samples taken at the main circulation channel of the bay, Paquetá Island, and the two sites mentioned before. The ³H-leucine curves showed similar pattern for all studied areas, indicating the ideal isotope concentration to be 10 nM. Bacterial biomass production ranged from 0.40 to 4.53 µgC L-1 h-1 in Urca and from 3.86 to 73.72 µgC L-1 h-1 in Governador Island indicating the relationship between nutrients and organic matter supply and bacterial productivity. This work is an important reference for studies on trophodynamics, biogeochemical cycles and modelling in Guanabara Bay.

Contribution of large bacteria to bacterial biomass in a deep freshwater lake (Lake Biwa, Japan)

2020 ◽  
Vol 85 ◽  
pp. 131-139
Author(s):  
S Shen ◽  
Y Shimizu
Keyword(s):  
Cell Volume ◽  
Bacterial Cell ◽  
Lake Biwa ◽  
Bacterial Biomass ◽  
Spatial Variations ◽  
Freshwater Lake ◽  
Heterotrophic Nanoflagellates ◽  
Bacterial Productivity ◽  
Transmission Electron ◽  
Seasonal And Spatial Variations

Despite the importance of bacterial cell volume in microbial ecology in aquatic environments, literature regarding the effects of seasonal and spatial variations on bacterial cell volume remains scarce. We used transmission electron microscopy to examine seasonal and spatial variations in bacterial cell size for 18 mo in 2 layers (epilimnion 0.5 m and hypolimnion 60 m) of Lake Biwa, Japan, a large and deep freshwater lake. During the stratified period, we found that the bacterial cell volume in the hypolimnion ranged from 0.017 to 0.12 µm3 (median), whereas that in the epilimnion was less variable (0.016 to 0.033 µm3, median) and much lower than that in the hypolimnion. Additionally, in the hypolimnion, cell volume during the stratified period was greater than that during the mixing period (up to 5.7-fold). These differences in cell volume resulted in comparable bacterial biomass in the hypolimnion and epilimnion, despite the fact that there was lower bacterial abundance in the hypolimnion than in the epilimnion. We also found that the biomass of larger bacteria, which are not likely to be grazed by heterotrophic nanoflagellates, increased in the hypolimnion during the stratified period. Our data suggest that estimation of carbon flux (e.g. bacterial productivity) needs to be interpreted cautiously when cell volume is used as a constant parametric value. In deep freshwater lakes, a difference in cell volume with seasonal and spatial variation may largely affect estimations.

Estimation of bacterial production in fresh waters by the simultaneous measurement of [35S]Sulphate and D-[3H]glucose uptake in the dark

1978 ◽  
Vol 24 (8) ◽  
pp. 939-946 ◽  
Author(s):  
P. G. C. Campbell ◽  
J. H. Baker
Keyword(s):  
Bacterial Production ◽  
Membrane Filter ◽  
Outer Edge ◽  
Size Fractionation ◽  
Sulphate Uptake ◽  
Uptake Rates ◽  
Chalk Stream ◽  
Glucose Assimilation ◽  
Heterotrophic Production

Sulphate uptake in the dark by phytoplankton constitutes a severe limitation to the determination of bacterial heterotrophic production from sulphate-uptake rates. Consequently a modification to the 35S-method has been developed involving size fractionation to separate the algae from the bacteria. Both the whole water sample and the algae-free filtrate are incubated in the dark with trace quantities of [3H]glucose, whereas the filtrate alone is incubated with 35SO4. The experimental determined ratio (whole sample glucose assimilation: filtrate glucose assimilation) is used to correct the measured sulphate uptake (filtrate) and yields an estimate of bacterial sulphate uptake in the whole sample.A potential filtration artefact has been demonstrated in the 35SO4 uptake methodology. Excision of the outer edge of the membrane filter and counting of the inner wetted circle alone eliminated this problem and significantly improved the analytical performance of the method: coefficient of variation ~ 5%, detection limit ~ 2 ng S ℓ−1 h−1. The modified [35SO4]–[3H]-glucose method was applied to samples from an English chalk stream: bacterial sulphate uptake was higher during the spring diatom maximum (10.6 ng S ℓ−1 h−1) than 3 weeks later when detritus dominated the seston (4.9 ng S ℓ−1 h−1). We estimate the corresponding rates of formation of particulate (bacterial) carbon to be 0.53 and 0.24 μg C ℓ−1 h−1 respectively.

scholarly journals Fe and C co-limitation of heterotrophic bacteria in the naturally fertilized region off the Kerguelen Islands

2015 ◽  
Vol 12 (6) ◽  
pp. 1983-1992 ◽  
Author(s):  
I. Obernosterer ◽  
M. Fourquez ◽  
S. Blain
Keyword(s):  
Trace Metal ◽  
Bacterial Production ◽  
Bacterial Abundance ◽  
Heterotrophic Bacteria ◽  
Kerguelen Islands ◽  
High Nutrient ◽  
Limiting Nutrient ◽  
Heterotrophic Metabolism ◽  
Heterotrophic Production

Abstract. It has been univocally shown that iron (Fe) is the primary limiting nutrient for phytoplankton metabolism in high-nutrient, low-chlorophyll (HNLC) waters, yet the question of how this trace metal affects heterotrophic microbial activity is far less understood. We investigated the role of Fe for bacterial heterotrophic production and growth at three contrasting sites in the naturally Fe-fertilized region east of the Kerguelen Islands and at one site in HNLC waters during the KEOPS2 (Kerguelen Ocean and Plateau Compared Study 2) cruise in spring 2011. We performed dark incubations of natural microbial communities amended either with iron (Fe, as FeCl3) or carbon (C, as trace-metal clean glucose), or a combination of both, and followed bacterial abundance and heterotrophic production for up to 7 days. Our results show that single and combined additions of Fe and C stimulated bulk and cell-specific bacterial production at the Fe-fertilized sites, while in HNLC waters only combined additions resulted in significant increases in these parameters. Bacterial abundance was enhanced in two out of the three experiments performed in Fe-fertilized waters but did not respond to Fe or C additions in HNLC waters. Our results provide evidence that both Fe and C are present at limiting concentrations for bacterial heterotrophic activity in the naturally fertilized region off the Kerguelen Islands in spring, while bacteria were co-limited by these elements in HNLC waters. These results shed new light on the role of Fe in bacterial heterotrophic metabolism in regions of the Southern Ocean that receive variable Fe inputs.

scholarly journals Comparison of bacterial production in the water column between two Arctic fjords, Hornsund and Kongsfjorden (West Spitsbergen)

Oceanologia ◽  
2017 ◽  
Vol 59 (4) ◽  
pp. 496-507 ◽  
Author(s):  
Anetta Ameryk ◽  
Katarzyna M. Jankowska ◽  
Agnieszka Kalinowska ◽  
Jan M. Węsławski
Keyword(s):  
Water Column ◽  
Bacterial Production ◽  
West Spitsbergen ◽  
Arctic Fjords

Empirical Relationships between Bacterial Abundance and Chlorophyll Concentration in Fresh and Marine Waters

1984 ◽  
Vol 41 (7) ◽  
pp. 1015-1023 ◽  
Author(s):  
D. F. Bird ◽  
J. Kalff
Keyword(s):  
Bacterial Abundance ◽  
Regression Line ◽  
Empirical Relationship ◽  
Chlorophyll Concentration ◽  
Bacterial Biomass ◽  
Regression Equations ◽  
Bacterial Productivity ◽  
Marine Waters ◽  
Lake Metabolism ◽  
Chl A

A strong, positive empirical relationship was found between bacterial abundance and chlorophyll concentration in fresh and marine waters. Freshwater and marine linear regression equations are statistically indistinguishable. The overall equation is log AODC = 5.867 + 0.776 log chl a, r2 = 0.88, where AODC (acridine orange direct count) is the number of bacteria per millilitre and chl a is micrograms of chlorophyll a per litre. It is apparent that planktonic bacteria and algae are tightly linked in lakes and the sea. The slope of the regression line, however, shows that bacterial numbers do not increase as rapidly as algal biomass with an increase in nutrient concentration. We suggest that this disproportionately smaller increase in bacterial numbers need not signify a smaller role for bacteria in lake metabolism with increasing nutrient availability, if bacterial productivity per unit bacterial biomass increases as total bacterial biomass increases between systems.

Sign in / Sign up

Export Citation Format

Share Document