scholarly journals Dissolved Organic Carbon Influences Microbial Community Composition and Diversity in Managed Aquifer Recharge Systems

2012 ◽  
Vol 78 (19) ◽  
pp. 6819-6828 ◽  
Author(s):  
Dong Li ◽  
Jonathan O. Sharp ◽  
Pascal E. Saikaly ◽  
Shahjahan Ali ◽  
Mazahirali Alidina ◽  
...  
Keyword(s):  
Microbial Community ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Microbial Community Composition ◽  
Managed Aquifer Recharge ◽  
Aquifer Recharge ◽  
Infiltration Depth ◽  
Content Type ◽  
South Platte River ◽  
Doc Concentration

ABSTRACTThis study explores microbial community structure in managed aquifer recharge (MAR) systems across both laboratory and field scales. Two field sites, the Taif River (Taif, Saudi Arabia) and South Platte River (Colorado), were selected as geographically distinct MAR systems. Samples derived from unsaturated riverbed, saturated-shallow-infiltration (depth, 1 to 2 cm), and intermediate-infiltration (depth, 10 to 50 cm) zones were collected. Complementary laboratory-scale sediment columns representing low (0.6 mg/liter) and moderate (5 mg/liter) dissolved organic carbon (DOC) concentrations were used to further query the influence of DOC and depth on microbial assemblages. Microbial density was positively correlated with the DOC concentration, while diversity was negatively correlated at both the laboratory and field scales. Microbial communities derived from analogous sampling zones in each river were not phylogenetically significantly different on phylum, class, genus, and species levels, as determined by 16S rRNA gene pyrosequencing, suggesting that geography and season exerted less sway than aqueous geochemical properties. When field-scale communities derived from the Taif and South Platte River sediments were grouped together, principal coordinate analysis revealed distinct clusters with regard to the three sample zones (unsaturated, shallow, and intermediate saturated) and, further, with respect to DOC concentration. An analogous trend as a function of depth and corresponding DOC loss was observed in column studies. Canonical correspondence analysis suggests that microbial classesBetaproteobacteriaandGammaproteobacteriaare positively correlated with DOC concentration. Our combined analyses at both the laboratory and field scales suggest that DOC may exert a strong influence on microbial community composition and diversity in MAR saturated zones.

scholarly journals Lack of Correlation between Turnover of Low-Molecular-Weight Dissolved Organic Carbon and Differences in Microbial Community Composition or Growth across a Soil pH Gradient

2011 ◽  
Vol 77 (8) ◽  
pp. 2791-2795 ◽  
Author(s):  
Johannes Rousk ◽  
Philip C. Brookes ◽  
Helen C. Glanville ◽  
David L. Jones
Keyword(s):  
Molecular Weight ◽  
Microbial Community ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Community Composition ◽  
Soil Ph ◽  
Predictive Power ◽  
Microbial Community Composition ◽  
Low Molecular Weight ◽  
Soil C

ABSTRACTWe studied how soil pH (pHs 4 to 8) influenced the mineralization of low-molecular-weight (LMW)-dissolved organic carbon (DOC) compounds, and how this compared with differences in microbial community structure. The mineralization of LMW-DOC compounds was not systematically connected to differences in soil pH, consistent with soil respiration. In contrast, the microbial community compositions differed dramatically. This suggests that microbial community composition data will be of limited use in improving the predictive power of soil C models.

scholarly journals Effect of Litter-Derived Dissolved Organic Carbon Addition on Forest Soil Microbial Community Composition

2021 ◽  
Vol 1 ◽  
Author(s):  
Min Wang ◽  
Qiuxiang Tian ◽  
Chang Liao ◽  
Rudong Zhao ◽  
Feng Liu
Keyword(s):  
Microbial Community ◽  
Microbial Biomass ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Community Composition ◽  
Soil Microbial Biomass ◽  
Microbial Community Composition ◽  
Soil Microbial ◽  
Significant Difference ◽  
Microbial Groups

The input of dissolved organic carbon (DOC) into soil affects soil organic carbon mineralization and microbial community composition by changing carbon availability. However, up to now, there is little knowledge about the microbial groups that utilize the added DOC and how the incorporation process may vary over time. In this study, we added 13C-labeled litter-derived DOC (treatment) or pure water (control) to a forest soil from different layers to investigate the effects of DOC addition on soil microbial biomass and community composition in a 180-d laboratory incubation experiment. Soil microbial phospholipid fatty acid (PLFA) were measured to assess changes in the microbial community composition. The 13C incorporation into microbial biomass and PLFAs was analyzed to trace the microbial utilization of litter-derived DOC. Our results indicated that DOC addition increased the biomass of gram-negative bacteria, gram-positive bacteria, fungi, and actinomycetes, but the microbial community composition manifested a similar trend for both treatment and control soils at the end of incubation. Proportions of added DOC in different depths of soil microbial PLFAs had no significant difference. Moreover, 17:0 cy and 15:0 PLFAs which are described as the bacterial biomarkers had a greater amount of 13C incorporation than other PLFAs for the topsoil, which indicated that 13C-labeled litter-derived DOC was more easily assimilated by some specific bacterial community. Soil microbial biomass and the incorporation of 13C into PLFA reached its maximum around 30 days after DOC addition and then rapidly reduced to the level comparable to control. Overall, this study demonstrated that the incorporation of 13C-labeled litter-derived DOC into PLFA in different depth soil had no significant difference, and the incorporation of 13C by bacteria was higher than other microbial groups.

scholarly journals Three representative UK moorland soils show differences in decadal release of dissolved organic carbon in response to environmental change

2011 ◽  
Vol 8 (12) ◽  
pp. 3661-3675 ◽  
Author(s):  
M. I. Stutter ◽  
D. G. Lumsdon ◽  
A. P. Rowland
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Environmental Change ◽  
Soil Properties ◽  
Process Models ◽  
Environmental Drivers ◽  
Specific Response ◽  
Soil C ◽  
Doc Concentration ◽  
Mineral Soils

Abstract. Moorland carbon reserves in organo-mineral soils may be crucial to predicting landscape-scale variability in soil carbon losses, an important component of which is dissolved organic carbon (DOC). Surface water DOC trends are subject to a range of scaling, transport and biotic processes that disconnect them from signals in the catchment's soils. Long-term soil datasets are vital to identify changes in DOC release at source and soil C depletion. Here we show, that moorland soil solution DOC concentrations at three key UK Environmental Change Network sites increased between 1993–2007 in both surface- and sub- soil of a freely-draining Podzol (48 % and 215 % increases in O and Bs horizons, respectively), declined in a gleyed Podzol and showed no change in a Peat. Our principal findings were that: (1) considerable heterogeneity in DOC response appears to exist between different soils that is not apparent from the more consistent observed trends for streamwaters, and (2) freely-draining organo-mineral Podzol showed increasing DOC concentrations, countering the current scientific focus on soil C destabilization in peats. We discuss how the key solubility controls on DOC associated with coupled physico-chemical factors of ionic strength, acid deposition recovery, soil hydrology and temperature cannot readily be separated. Yet, despite evidence that all sites are recovering from acidification the soil-specific responses to environmental change have caused divergence in soil DOC concentration trends. The study shows that the properties of soils govern their specific response to an approximately common set of broad environmental drivers. Key soil properties are indicated to be drainage, sulphate and DOC sorption capacity. Soil properties need representation in process-models to understand and predict the role of soils in catchment to global C budgets. Catchment hydrological (i.e. transport) controls may, at present, be governing the more ubiquitous rises in river DOC concentration trends, but soil (i.e. source) controls provide the key to prediction of future C loss to waters and the atmosphere.

Carbocentric limnology: looking back, looking forward

2008 ◽  
Vol 65 (3) ◽  
pp. 543-548 ◽  
Author(s):  
Yves T Prairie
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Microbial Community ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Carbon Budget ◽  
Metabolic Balance ◽  
Lake Ecosystems ◽  
Looking Back ◽  
Landscape Level

In this perspective article, I argue that dissolved organic carbon occupies a central role in the functioning of lake ecosystems, comparable in importance to that played by nutrients. Because lakes receive so much dissolved organic carbon from the terrestrial landscape, its accumulation in water bodies usually represents the largest pool of lacustrine organic matter within the water column. The transformation of even a small fraction of this external carbon by the microbial community can alter significantly the metabolic balance of lake ecosystems, simultaneously releasing carbon dioxide to the atmosphere and burying organic carbon in lake sediments. At the landscape level, even if they occupy a small fraction of the landscape, lakes play a surprisingly important role in the regional carbon budget, particularly when considered at the appropriate temporal scale.

scholarly journals The effect of dissolved organic carbon on pelagial and near-sediment water traits in lakes

2011 ◽  
Vol 74 (2) ◽  
pp. 133-139 ◽  
Author(s):  
Krzysztof Banaś
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Redox Potential ◽  
Environmental Conditions ◽  
Calcium Concentration ◽  
Total Hardness ◽  
Sediment Layer ◽  
Ph Values ◽  
Doc Concentration ◽  
Good Transparency

The effect of dissolved organic carbon (DOC) on the environmental conditions of macrophytes has been studied in 35 lakes divided into soft- and hardwater: oligohumic (&lt;4.0 mg C dm<sup>-3</sup>), α-mesohumic (4.0-8.0 mg C dm<sup>-3</sup>), β-mesohumic (8.1-16.0 mg C dm<sup>-3</sup>) and polihumic (&gt;16.0 mg C dm<sup>-3</sup>). The optimum environmental conditions for macrophytes have been found in oligohumic lakes, characterised by low water colour and its good transparency. In soft- and hardwater lakes increasing concentration of DOC is accompanied with an increase in the colour (r=0.95), while the visibility decreases. With increasing DOC in the near-sediment layer the pH values decrease while the concentration of nitrogen increases and the concentration of phosphorus slightly increases. In hardwater lakes with increasing DOC concentration, the redox potential, conductivity, total hardness and calcium concentration in the near-sediment water decrease, whereas the content of CO<sup>2</sup> remains at a very low level.

Sign in / Sign up

Export Citation Format

Share Document