scholarly journals Microbiology of a northern river: bacterial distribution and relationship to suspended sediment and organic carbon

1979 ◽  
Vol 25 (9) ◽  
pp. 1058-1062 ◽  
Author(s):  
G. G. Geesey ◽  
J. W. Costerton
Keyword(s):  
Organic Carbon ◽  
Suspended Sediment ◽  
Mining Operations ◽  
Free Living ◽  
Athabasca River ◽  
Turbid Waters ◽  
Northern River ◽  
High Concentrations ◽  
Northeastern Alberta ◽  
Carbon Concentrations

Epifluorescent microscopy showed as many as 4 × 106 bacteria/mL in the turbid waters of the Athabasca River near the tar sand deposits in northeastern Alberta. The numbers were usually similar upstream and downstream (60 km) from pilot-mining operations. The majority of bacteria existed as free-living cells in spite of the fact there were high concentrations of suspended sediment present (average 220 mg/L) during the ice-free period. Fluctuations in bacterial concentration were positively correlated (r = 0.86, P < 0.05) with total organic carbon concentrations in the river water.

Total organic carbon and the preservation of organic-walled microfossils in Precambrian shale

Geology ◽  
2020 ◽  
Author(s):  
C.R. Woltz ◽  
S.M. Porter ◽  
H. Agić ◽  
C.M. Dehler ◽  
C.K. Junium ◽  
...  
Keyword(s):  
Species Richness ◽  
Organic Carbon ◽  
Total Organic Carbon ◽  
Microbial Degradation ◽  
Sedimentation Rate ◽  
Surface Pattern ◽  
Causal Factors ◽  
Eukaryotic Diversity ◽  
High Concentrations ◽  
Fossil Preservation

Much of our understanding of early eukaryote diversity and paleoecology comes from the record of organic-walled microfossils in shale, yet the conditions controlling their preservation are not well understood. It has been suggested that high concentrations of total organic carbon (TOC) inhibit the preservation of organic fossils in shale, and although this idea is supported anecdotally, it has never been tested. Here we compared the presence, preservational quality, and assemblage diversity of organic-walled microfossils to TOC concentrations of 346 shale samples that span the late Paleoproterozoic to middle Neoproterozoic in age. We found that fossil-bearing samples have significantly lower median TOC values (0.32 wt%, n = 189) than those containing no fossils (0.72 wt%, n = 157). Preservational quality, measured by the loss of surface pattern, density of pitting, and deterioration of wall margin, decreases as TOC increases. Species richness negatively correlates with TOC within the ca. 750 Ma Chuar Group (Arizona, USA), but no relationship is observed in other units. These results support the hypothesis that high TOC content either decreases the preservational quality or inhibits the preservation of organic-walled microfossils altogether. However, it is also possible that other causal factors, including sedimentation rate and microbial degradation, account for the correlation between fossil preservation and TOC. We expect that as TOC varies in space and time, so too does the probability of finding well-preserved fossils. A compilation of 13,940 TOC values spanning Earth history suggests significantly higher median TOC levels in Mesoproterozoic versus Neoproterozoic shale, potentially biasing the interpreted pattern of increased eukaryotic diversity in the Tonian.

scholarly journals First-Time Source Apportionment Analysis of Deposited Particulate Matter from a Moss Biomonitoring Study in Northern Greece

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 208 ◽  
Author(s):  
Chrysoula Betsou ◽  
Evangelia Diapouli ◽  
Evdoxia Tsakiri ◽  
Lambrini Papadopoulou ◽  
Marina Frontasyeva ◽  
...  
Keyword(s):  
Source Apportionment ◽  
Power Plants ◽  
Soil Dust ◽  
Northern Greece ◽  
Mining Operations ◽  
Moss Species ◽  
Elemental Concentrations ◽  
Pmf Model ◽  
Moss Biomonitoring ◽  
High Concentrations

Moss biomonitoring is a widely used technique for monitoring the accumulation of trace elements in airborne pollution. A total of one hundred and five samples, mainly of the Hypnum cupressiforme Hedw. moss species, were collected from the Northern Greece during the 2015/2016 European ICP Vegetation (International Cooperative Program on Effects of Air Pollution on Natural Vegetation and Crops) moss survey, which also included samples from the metalipherous area of Skouries. They were analyzed by means of neutron activation analysis, and the elemental concentrations were determined. A positive matrix factorization (PMF) model was applied to the results obtained for source apportionment. According to the PMF model, five sources were identified: soil dust, aged sea salt, road dust, lignite power plants, and a Mn-rich source. The soil dust source contributed the most to almost all samples (46% of elemental concentrations, on average). Two areas with significant impact from anthropogenic activities were identified. In West Macedonia, the emissions from a lignite power plant complex located in the area have caused high concentrations of Ni, V, Cr, and Co. The second most impacted area was Skouries, where mining activities and vehicular traffic (probably related to the mining operations) led to high concentrations of Mn, Ni, V, Co, Sb, and Cr.

scholarly journals Oxygen consumption during mineralization of organic compounds in water samples from a small sub-tropical reservoir (Brazil)

2003 ◽  
Vol 46 (4) ◽  
pp. 723-729 ◽  
Author(s):  
Marcela Bianchessi da Cunha-Santino ◽  
Irineu Bianchini Júnior
Keyword(s):  
Oxygen Consumption ◽  
Organic Carbon ◽  
Organic Compounds ◽  
Tannic Acid ◽  
Theoretical Calculations ◽  
Tropical Reservoir ◽  
First Order ◽  
First Order Kinetics ◽  
Mineralization Processes ◽  
Carbon Concentrations

Assays were carried out to evaluate the oxygen consumption resulting from mineralization of different organic compounds: glucose, sucrose, starch, tannic acid, lysine and glycine. The compounds were added to 1 l of water sample from Monjolinho Reservoir. Dissolved oxygen and dissolved organic carbon were monitored during 20 days and the results were fitted to first order kinetics model. During the 20 days of experiments, the oxygen consumption varied from 4.5 mg.l-1 (tannic acid) to 71.5 mg.l-1 (glucose). The highest deoxygenation rate (kD) was observed for mineralization of tannic acid (0.321 day-1) followed by glycine, starch, lysine, sucrose and glucose (0.1004, 0.0504, 0.0486, 0.0251 and 0.0158 day-1, respectively). From theoretical calculations and oxygen and carbon concentrations we obtained the stoichiometry of the mineralization processes. Stoichiometric values varied from 0.17 (tannic acid) to 2.55 (sucrose).

Predicting soil organic carbon concentrations in a low relief landscape, eastern Iran

2018 ◽  
Vol 15 ◽  
pp. e00195 ◽  
Author(s):  
Mohammad Reza Pahlavan-Rad ◽  
Khodadad Dahmardeh ◽  
Colby Brungard
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Eastern Iran ◽  
Carbon Concentrations

Dissolved organic carbon concentrations and fluxes along the Moisie River, Quebec

1990 ◽  
Vol 24 (1) ◽  
pp. 35-42 ◽  
Author(s):  
T. E. FORD ◽  
S. A. FORD ◽  
M. A. LOCK ◽  
R. J. NAIMAN
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Carbon Concentrations
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