Benthic Bacterial Biomass and Production in Two Blackwater Rivers

1986 ◽  
Vol 43 (6) ◽  
pp. 1271-1276 ◽  
Author(s):  
Stuart Findlay ◽  
Judy L. Meyer ◽  
Rebecca Risley
Keyword(s):  
Water Chemistry ◽  
Thymidine Incorporation ◽  
Standing Stock ◽  
Bacterial Biomass ◽  
Organic Content ◽  
Growth Substrate ◽  
Sediment Bacteria ◽  
Allochthonous Detritus ◽  
Blackwater Rivers ◽  
Direct Counts

Bacterial biomass and production in sediments of two blackwater rivers were measured via epifluorescent direct counts and rate of thymidine incorporation into DNA. Biomass ranged from 3 to 1500 mg C∙m−2 and production ranged from 0.01 to 22.0 mg C∙m−2∙h−1. Both biomass and production were correlated with organic content of the sediment. Neither biomass nor production was related to temperature. Allochthonous detritus apparently serves as a growth substrate for sediment bacteria. Despite differences in water chemistry and flow between the two rivers, comparison of similar sites between rivers showed similar bacterial standing stock and production. During most of the year these fourth- and sixth-order rivers are highly heterotrophic, yet at low water autochthonous carbon may serve as growth substrate for bacteria.

A direct viable counting method for measuring tolerance of aquatic microbial communities to Hg2+

1988 ◽  
Vol 34 (9) ◽  
pp. 1090-1095 ◽  
Author(s):  
Cynthia Liebert ◽  
Tamar Barkay
Keyword(s):  
Natural Waters ◽  
Thymidine Incorporation ◽  
Colony Growth ◽  
Growth Substrate ◽  
Counting Method ◽  
Aquatic Communities ◽  
Microbial Process ◽  
Heterotrophic Activity ◽  
Direct Counts ◽  
Resistant Cells

Direct counts of Hg2+ resistant cells in natural waters were obtained by fluorescence microscopy after incubation for 20 h in the presence of a growth substrate, nalidixic acid to halt cell division, and inhibiting concentrations of Hg2+. This method discriminated Hg2+ resistant from Hg2+ sensitive Escherichia coli strains. Estuarine samples were used to compare this procedure with two other toxicity measurements that determine the effect of Hg2+ on colony growth and on rates of radioactive thymidine incorporation into cellular material. Toxicity measurements based on direct viable counts and thymidine incorporation rates had comparable sensitivities, and both were 3–4 orders of magnitude more sensitive than the method that utilized colony counts. Thus, the direct enumeration of Hg2+ resistant cells is useful for predicting the potential of aquatic communities to sustain heterotrophic activity, an essential microbial process, in the presence of Hg2+.

scholarly journals Solutions to Problems in Enumerating Sediment Bacteria by Direct Counts †

1989 ◽  
Vol 55 (5) ◽  
pp. 1214-1219 ◽  
Author(s):  
Marc Schallenberg ◽  
Jacob Kalff ◽  
Joseph B. Rasmussen
Keyword(s):  
Sediment Bacteria ◽  
Direct Counts

Boosted microbial productivity during the Toarcian Oceanic Anoxic Event in the Paris Basin, France: new evidence from organic geochemistry and petrographic analysis

2021 ◽  
pp. SP514-2020-167
Author(s):  
Carolina Fonseca ◽  
João Graciano Mendonça Filho ◽  
Carine Lézin ◽  
François Baudin ◽  
António Donizeti de Oliveira ◽  
...  
Keyword(s):  
Marine Environment ◽  
Organic Geochemistry ◽  
Bacterial Biomass ◽  
Integrated Approach ◽  
Organic Content ◽  
Marine Phytoplankton ◽  
Petrographic Analysis ◽  
Paris Basin ◽  
Oceanic Anoxic Event ◽  
Anoxic Event

AbstractThe Toarcian Oceanic Anoxic Event (T-OAE) is marked by major paleoenvironmental and paleoceanographical changes at a global scale, associated to a severe disturbance of the global carbon cycle, and organic-rich facies deposition. Here, a multi-proxy approach (petrographic and geochemical techniques) was applied to the study of the organic content of the T-OAE of the Paris Basin, whose phytoplanktonic origin has been previously inferred by its geochemical signature.The top of tenuicostatum Zone is characterized by palynomorphs and marine phytoplankton-derived amorphous organic matter (AOM), representing a proximal marine environment with emplacement of euxinic conditions to the top (total organic carbon/sulfur content and increase in AOM). At the base of the serpentinum Zone the proliferation of bacterial biomass begins, with phytoplankton playing a secondary role. This indicates the development of stagnant and restrictive conditions in a proximal environment, with water column stratification (neohop-13(18)-ene). The majority of the serpentinum Zone is dominated by bacterial biomass, suggesting a marine environment with bottom waters stagnation, possibly related to basin paleogeomorphology and circulation patterns, with episodic euxinia.This therefore suggests that the T-OAE organic fraction is dominated by bacterial biomass, not phytoplankton, showing the importance of an integrated approach to the determination of the organic facies.

Bacterial population dynamics, production, and heterotrophic activity in a recently formed reservoir

1999 ◽  
Vol 45 (9) ◽  
pp. 747-753 ◽  
Author(s):  
Louis B Jugnia ◽  
Rémy D Tadonléké ◽  
T Sime-Ngando ◽  
J Devaux ◽  
C Andrivon
Keyword(s):  
Primary Production ◽  
Chlorophyll A ◽  
Biomass Production ◽  
Resource Availability ◽  
Bacterial Production ◽  
Standing Stock ◽  
Bacterial Biomass ◽  
Heterotrophic Activity ◽  
Chlorophyll A Concentration ◽  
Biological Variables

Seasonal and spatial fluctuations in abundance, biomass production, and potential heterotrophic activity (i.e., 14C-glucose uptake) of bacterioplankton assemblages in a 1-year-old reservoir (the Sep Reservoir, Puy-de-Dôme, France) were examined concurrently with water temperature, phytoplankton chlorophyll a concentration, and primary production (PP). Based on the values observed for these biological variables, the Sep Reservoir was considered to have evolved to an oligo-mesotrophic state. Spatiotemporal variations of bacterial variables were a consequence of the seasonal evolution of the reservoir coupled with the resource availability. Multivariate regression analyses suggest that about 14 and 26% of the variance in bacterial standing stock and activity may be explained by the physical environment (i.e., temperature) and a resource availability index (chlorophyll a concentration or primary production), respectively. A carbon budget indicated that 4-126% (mean = 20%) of the ambient PP may be channeled through the microbial loop via bacterial biomass production. Heterotrophic bacterial production in the Sep Reservoir may therefore, on occasion, represent a significant source of carbon for higher order consumers.Key words: reservoirs, plankton, bacteria, heterotrophic uptake, primary and bacterial production.

The Coupling of Heterotrophic Bacterial and Phytoplankton Production in a Hypertrophic, Shallow Prairie Lake

1994 ◽  
Vol 51 (10) ◽  
pp. 2219-2226 ◽  
Author(s):  
Richard D. Robarts ◽  
Michael T. Arts ◽  
Marlene S. Evans ◽  
Marley J. Waiser
Keyword(s):  
Primary Production ◽  
Bacterial Production ◽  
Thymidine Incorporation ◽  
Chlorophyll Concentration ◽  
Bacterial Biomass ◽  
Cyanobacterial Blooms ◽  
Dominant Factor ◽  
Phytoplankton Production ◽  
Carbon Production ◽  
Prairie Lakes

Data from hypertrophic Humboldt Lake (Zmax = 6 m), Saskatchewan, support published studies indicating that bacterial numbers and production do not increase proportionally with chlorophyll concentration and primary production. There was no compensation for these relationships with increased bacterial production per cell, but our data showed an increase in production per unit bacterial biomass (273 fmol TdR∙μg C−1∙h−1). Bacterial production (19.8–422 mg C∙m−2∙d−1) was correlated with primary production (r = 0.76), and maximum bacterial production coincided with summer cyanobacterial blooms. Water temperature was a dominant factor correlated with bacterial production (r = 0.85) and growth (r = 0.92). Depending upon the factors used to convert the rate of thymidine incorporation to gross carbon production, heterotrophic bacterial production was able to consume an average of 42% (408 mg C∙m−2∙d−1) to 67% (653 mg C∙m−2∙d−1) of plankton primary productivity. Based on these calculations, hypertrophic prairie lakes might accumulate autochthonously produced organic carbon, but this conclusion takes no account of benthic bacterial production which could be high in shallow lakes.

Microbial Leaf Decomposition in Adirondack Streams Exhibiting pH Gradients

1992 ◽  
Vol 49 (9) ◽  
pp. 1916-1923 ◽  
Author(s):  
Marcy P. Osgood ◽  
Charles W. Boylen
Keyword(s):  
New York ◽  
Water Chemistry ◽  
Acer Saccharum ◽  
Thymidine Incorporation ◽  
New York State ◽  
Bacterial Productivity ◽  
Ph Gradients ◽  
Microbial Decomposition ◽  
Ph Values ◽  
Water Ph

The effects of water pH and related water chemistry parameters on microbial decomposition processes were studied in three small, low-order woodland streams located in the Adirondack region of New York State. These streams exhibited spatial and seasonal gradients in water pH ranging from pH values of 4.5 to 7.0. Measurements of microbial biomass (ATP), bacterial numbers, and bacterial production (thymidine incorporation) on leaves of Acer saccharum were made over a 9-mo period (fall to spring). Decomposition of A. saccharum leaves was significantly decreased at lower pH. The developing epiphytic microbial community was affected in a very specific way. Bacterial numbers were not related to water pH values, nor were ATP measurements significantly correlated with pH or any pH-related water chemistry variable. However, thymidine incorporation by bacteria on leaf material (used as a measure of bacterial productivity) was significantly decreased at lower pH. This was the only consistent indicator of reduced microbial activity in response to acidification of these streams.

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.

Species Density and Lead (Pb) Pollution in Mangrove Ecosystem, South Kalimantan

2020 ◽  
Vol 5 (1) ◽  
pp. 70-81
Author(s):  
Anang Kadarsah ◽  
Dafiuddin Salim ◽  
Sadang Husain ◽  
Marta Dinata
Keyword(s):  
Heavy Metal ◽  
Oil Palm ◽  
Ph Value ◽  
Coal Mines ◽  
Organic Matter Content ◽  
Mangrove Ecosystem ◽  
Organic Content ◽  
Species Density ◽  
Pb Pollution ◽  
Mangrove Ecosystems

Its crucial to get information about lead (Pb) heavy metal pollution from mining and oil palm plantation on species density in mangrove ecosystem, to anticipate its impacts. This study aimed is to compare the types and densities of vegetation in mangrove ecosystems allegedly due to mining in Setarap village, Tanah Bumbu Regency and oil palm plantations in Kuala Tambangan Village, Tanah Laut Regency. We also analysis the condition of waters (TDS, pH and DO) and organic content in sediments to acquire data from the South Kalimantan mangrove ecosystems. The results showed there were four species of true mangroves (Avicennia alba, Acanthus ebracteatus, Nypa fruticans and Rhizophora apiculate) could live well in the environment affected by mining or oil palm plantations. The species density for trees was low (933 ind/ha) for mangroves affected by coal mines, while those affected by oil palm plantations had higher densities (1,067 ind/ha). pH value of waters in affected area by coal mining showed more acidic value (pH 5.76) especially at the back, while those by palm oil plantations are more acidic (pH 6) in the estuary. Organic matter content in sediments affected by coal mines was in the range of 0.61-6.59%, while those affected by oil palm plantations showed higher values (0.12-2.19%). Lead heavy metal content (Pb) in waters affected by coal mines was 0.031-0.056 mg/L, while the area affected by oil palm plantations was of higher value (0.110-0.128 mg/L). Lead (Pb) levels in sediments indicate higher values than waters, which reach 3.512-6.046 mg/Kg (affected by coal mines), and in areas affected by oil palm plantations reaching 6.658-6.66 mg/Kg. The general conclusion is that vegetation densities in areas affected by coal mines are lower than oil palm plantations. The level of lead  (Pb) pollution in the sediments is higher than in the waters.

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