scholarly journals Microbial Assemblages in Pressurized Antarctic Brine Pockets (Tarn Flat, Northern Victoria Land): A Hotspot of Biodiversity and Activity

2019 ◽  
Vol 7 (9) ◽  
pp. 333 ◽  
Author(s):  
Maria Papale ◽  
Angelina Lo Giudice ◽  
Antonella Conte ◽  
Carmen Rizzo ◽  
Alessandro C. Rappazzo ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Methanogenic Archaea ◽  
Integrated Approach ◽  
Diversity Indices ◽  
Upward Movement ◽  
Ice Shelf ◽  
Sulphate Reducing Bacteria ◽  
Ross Ice Shelf ◽  
New Generation ◽  
Reducing Bacteria

Two distinct pressurized hypersaline brine pockets (named TF4 and TF5), separated by a thin ice layer, were detected below an ice-sealed Antarctic lake. Prokaryotic (bacterial and archaeal) diversity, abundances (including virus-like particles) and metabolic profiles were investigated by an integrated approach, including traditional and new-generation methods. Although similar diversity indices were computed for both Bacteria and Archaea, distinct bacterial and archaeal assemblages were observed. Bacteroidetes and Gammaproteobacteria were more abundant in the shallowest brine pocket, TF4, and Deltaproteobacteria, mainly represented by versatile sulphate-reducing bacteria, dominated in the deepest, TF5. The detection of sulphate-reducing bacteria and methanogenic Archaea likely reflects the presence of a distinct synthrophic consortium in TF5. Surprisingly, members assigned to hyperthermophilic Crenarchaeota and Euryarchaeota were common to both brines, indicating that these cold habitats host the most thermally tolerant Archaea. The patterns of microbial communities were different, coherently with the observed microbiological diversity between TF4 and TF5 brines. Both the influence exerted by upward movement of saline brines from a sub-surface anoxic system and the possible occurrence of an ancient ice remnant from the Ross Ice Shelf were the likely main factors shaping the microbial communities.

A Case Study of a Ross Ice Shelf Airstream Event: A New Perspective*

2009 ◽  
Vol 137 (11) ◽  
pp. 4030-4046 ◽  
Author(s):  
Daniel F. Steinhoff ◽  
Saptarshi Chaudhuri ◽  
David H. Bromwich
Keyword(s):  
Large Scale ◽  
Model Performance ◽  
Thermal Infrared ◽  
Integrated Approach ◽  
Cloud Formation ◽  
Synoptic Scale ◽  
Ice Shelf ◽  
Low Level ◽  
Ross Ice Shelf

Abstract A case study illustrating cloud processes and other features associated with the Ross Ice Shelf airstream (RAS), in Antarctica, is presented. The RAS is a semipermanent low-level wind regime primarily over the western Ross Ice Shelf, linked to the midlatitude circulation and formed from terrain-induced and large-scale forcing effects. An integrated approach utilizes Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery, automatic weather station (AWS) data, and Antarctic Mesoscale Prediction System (AMPS) forecast output to study the synoptic-scale and mesoscale phenomena involved in cloud formation over the Ross Ice Shelf during a RAS event. A synoptic-scale cyclone offshore of Marie Byrd Land draws moisture across West Antarctica to the southern base of the Ross Ice Shelf. Vertical lifting associated with flow around the Queen Maud Mountains leads to cloud formation that extends across the Ross Ice Shelf to the north. The low-level cloud has a warm signature in thermal infrared imagery, resembling a surface feature of turbulent katabatic flow typically ascribed to the RAS. Strategically placed AWS sites allow assessment of model performance within and outside of the RAS signature. AMPS provides realistic simulation of conditions aloft but experiences problems at low levels due to issues with the model PBL physics. Key meteorological features of this case study, within the context of previous studies on longer time scales, are inferred to be common occurrences. The assumption that warm thermal infrared signatures are surface features is found to be too restrictive.

Lifting the Lid: Nitrifying Archaea Sustain Diverse Microbial Communities Below the Ross Ice Shelf

2020 ◽  
Author(s):  
Clara Martínez-Pérez ◽  
Chris Greening ◽  
Zihao Zhao ◽  
Rachael J. Lappan ◽  
Sean K. Bay ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Ice Shelf ◽  
Ross Ice Shelf

Diversity and identification of methanogenic archaea and sulphate-reducing bacteria in sediments from a pristine tropical mangrove

2010 ◽  
Vol 97 (4) ◽  
pp. 401-411 ◽  
Author(s):  
Rodrigo Gouvêa Taketani ◽  
Caio Augusto Yoshiura ◽  
Armando Cavalcante Franco Dias ◽  
Fernando Dini Andreote ◽  
Siu Mui Tsai
Keyword(s):  
Methanogenic Archaea ◽  
Sulphate Reducing Bacteria ◽  
Reducing Bacteria

scholarly journals Cultivation and Molecular Studies to Reveal the Microbial Communities of Groundwaters Discharge Located in Hungary

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1533
Author(s):  
Marwene Toumi ◽  
Gorkhmaz Abbaszade ◽  
Yousra Sbaoui ◽  
Rózsa Farkas ◽  
Éva Ács ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Water Samples ◽  
Methanogenic Archaea ◽  
Amplicon Sequencing ◽  
Diversity Indices ◽  
High Ratio ◽  
Subsurface Water ◽  
Ammonia Oxidizer ◽  
Bacterial Phyla ◽  
Cell Counts

In the present study 12 water samples of five sampling sites (Tatabánya, Dandár, Szentendre, Szent Flórián and Ciprián groundwaters) known as nutrient-depleted aquatic environments were studied using amplicon sequencing (NGS) and cultivation techniques. Diversity indices and cell counts were determined to assess the species richness in relation to the cell counts within the samples, and the oligocarbophile growth capability of the isolated bacteria was tested in microtiter plates. Altogether, 55 bacterial phyla were identified from the samples by amplicon sequencing. The microbial communities of the different sampling times of the same sites did not differ significantly. Patescibacteria and Proteobacteria were present in all samples. Ciprián sample was dominated by Bacteroidetes, while in Dandár sample a high ratio of Chloroflexi was detected. Rokubacteria and WOR-1 dominated Szent Flórián sample and Tatabánya had a high number of Epsilonbacteraeota. Nine archaeal phyla were also detected; the samples were characterized by the presence of unclassified archaea and Nanoarchaeota, among them Woesearchaeia, as the most dominant. Crenarchaeota and Altiarchaeota were detected in high ratios in Dandár water samples. Among Thaumarchaeota the family Nitrosopumilaceae, and orders of Nitrosotaleales and Nitrososphaerales appeared in Szent Flórián and Tatabánya samples. Key organisms of the different biogeochemical cycles were discovered in these nutrient-depleted environments: methanogenic archaea, methanotrophic bacteria, ammonia oxidizer, nitrate reducers, diazotrophs, sulfate reducers, and sulfur oxidizer. Diversity indices and cell counts of the samples show negative correlation in case of bacteria and positive in case of archaea in Ciprián sample. The high diversity indices in Szentendre samples are connected to low cell counts, most probably due to the vulnerability of the groundwaters to the external environment factors which lead to the infiltration of soil microbes and contaminants to the water. The isolated bacteria were affiliated into four phyla, most of them belonging to Proteobacteria (59%) followed by Actinobacteria (21%), Firmicutes (17%) and Verrucomicrobia (1%). The members of the facultative chemolithotrophic genera of Sphingobium, Sphingomonas, Sphingopyxis were characterizing only Szentendre, Szent Flórián and Tatabánya samples. Only 10% of the isolated species showed an obligate oligocarbophile character. From the samples, a high number of novel bacterial taxa were cultivated. As a conclusion, our results confirmed the predominance of unclassified and unknown taxa in subsurface water, pointing to the importance and necessity of further studies to characterize these microbial populations.

scholarly journals Metagenomic analysis of soil samples collected from estuarine mangroves of Arabian Sea reveals rich microbiota and high numbers of sulphate reducing bacteria accompanied with methanogen bacteria

2019 ◽  
Author(s):  
Mandar S. Paingankar ◽  
Deepti D. Deobagkar
Keyword(s):  
Microbial Communities ◽  
Arabian Sea ◽  
Anthropogenic Activities ◽  
Geographical Location ◽  
Soil Samples ◽  
Rrna Gene ◽  
Illumina Platform ◽  
Sulphate Reducing Bacteria ◽  
Physico Chemical ◽  
Reducing Bacteria

AbstractThis study reports the analyses of the microbiome of the estuarine soil of mangroves of the Arabian Sea. Mangroves soil samples were collected from 12 locations of Arabian Sea coast of Maharashtra, India. 16S rRNA gene V3–V4 region amplicon sequencing was performed using the Miseq Illumina platform to identify the microbial communities present in the mangroves ecosystem. The metagenomics analysis provided an insight into the abundance, diversity and spatial variations in the mangrove microbial communities in relation to physico-chemical parameters and revealed that Proteobacteria, Flavobacteria and Planctomycetes are abundant in mangroves system. The differences in bacterial abundance, composition and diversity can partly be attributed to the physico-chemical characteristics of the samples, geographical location and anthropogenic activities in the locality. High numbers of sulphate reducing bacteria accompanied with methanogen bacteria were characteristic of Indian mangroves. The results obtained in the current study indicate rich species diversity and add valuable insights about the diversity of microbial communities of the mangroves in Maharashtra along the west coast of India and can provide better information for effective measures for conservation of mangroves. GIS based prediction suggest that the sulphur utilizing communities are under threat from anthropogenic activities and may decline in future if immediate measures are not implemented.

scholarly journals Microbial Communities and Sulphate-Reducing Bacteria in Soils Near Main-Gas Pipeline

2018 ◽  
Vol 80 (5) ◽  
pp. 3-14 ◽  
Author(s):  
D.R. Abdulina ◽  
◽  
L.M. Purish ◽  
G.O. Iutynska ◽  
◽  
...  
Keyword(s):  
Microbial Communities ◽  
Gas Pipeline ◽  
Sulphate Reducing Bacteria ◽  
Reducing Bacteria ◽  
Main Gas Pipeline

Investigation into Mechanisms of Microbial Effects on Iron and Manganese Transformations in Artificially Recharged Groundwater

1988 ◽  
Vol 20 (3) ◽  
pp. 47-53 ◽  
Author(s):  
Yan Bao-rui
Keyword(s):  
Groundwater Quality ◽  
Biochemical Reaction ◽  
Reaction Products ◽  
Injection Wells ◽  
Iron Bacteria ◽  
Sulphate Reducing Bacteria ◽  
Prevention And Treatment ◽  
Reducing Bacteria ◽  
Iron And Manganese ◽  
Microbial Effects

After artificial recharging of groundwater some problems occurred, such as changes in groundwater quality, the silting up of recharge (injection) wells, etc. Therefore, the mechanisms of microbial effects on groundwater quality after artificial recharging were studied in Shanghai and the district of Changzhou. These problems were approached on the basis of the amounts of biochemical reaction products generated by the metabolism of iron bacteria, sulphate-reducing bacteria, Thiobacillusthioparus, and Thiobacillusdenitrificans. The experiments showed that in the transformations occurring and the siltation of recharge wells, microorganisms play an important role, due to the various chemical and biochemical activities. A water-rock-microorganisms system is proposed, and some methods for the prevention and treatment of these effects are given.

Sign in / Sign up

Export Citation Format

Share Document