Spatial Variations in Microbial Compositions in a Karst Critical Zone in Samcheok, Republic of Korea

The effects of the unpredictability of the flow system in a karst area, with respect to bacterial communities in the aquatic environment, were evaluated. Bacterial communities from two different types of flow conditions (spring and sinkhole) were characterized and compared in the karst area. Proteobacteria, Bacteroidetes, and Verrucomicrobia were the major phyla present in the sampled spring and sinkhole waters. The water samples from the spring points were heavily loaded with Actinobacteria, especially Firmicutes, which accounted for 4.3% of the bacterial content. Furthermore, Actinobacteria were prevalent in some water samples, serving as indicators of the effects of seawater inundation. The richness and diversity of bacterial species were evaluated at the spring and sinkhole water points. The spring waters showed a higher bacterial richness and diversity compared to the sinkhole waters. Our results provide valuable information for the evaluation and investigation of microbial compositions in karst areas, which are characterized by heterogeneous hydrological conditions. The microbial species in karst areas are already exposed to changing hydrogeological conditions, and are likely to be confronted with future changes; thus, their spatiotemporal variations reflect the shifting baselines of physicochemical and ecosystem processes.

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Comparation study of soil genetic diversity of bacteria and fungi in different vegetation successions in a karst of Guizhou province, China

Acta Carsologica ◽

10.3986/ac.v50i2-3.7684 ◽

2021 ◽

Vol 50 (2-3) ◽

Author(s):

Yidong Mi ◽

Hongda Fang ◽

Tao Peng ◽

Min Zhou ◽

Xinru Li ◽

...

Keyword(s):

Genetic Diversity ◽

Bacterial Communities ◽

Secondary Forest ◽

Diversity Index ◽

Shannon Index ◽

Fungal Communities ◽

Karst Area ◽

Primary Forest ◽

Karst Areas ◽

Bacteria And Fungi

To study the soil genetic diversity of bacteria and fungi in different vegetation successions (grassland, shrubbery, primary forest and secondary forest) from the karst area, the Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) technology was applied. The results showed that: (1) the diversity of bacterial communities and the fungal communities in karst area were higher than non karst area in each vegetation succession. Compared with the survey from bacterial (the Shannon index was 2.97 in primary forest, 2.91 in secondary forest, 3.18 in shrubbery, 3.14 in grassland and 2.68 in non karst), fungal diversity between karst areas (the Shannon index was 3.56 in primary forest, 3.78 in secondary forest, 3.73 in shrubbery and 3.70 in grassland) and non karst areas (the Shannon index was 3.08) was more evident, which may be related to the alterations of the composition of plant community and the source of carbon in soil with the vegetation succession of karst ecosystem; (2) The comparation of bacterial diversity index and the richness comprehensively evaluated as follows: shrubbery > grassland > primary forest > nsecondary forest. The diversity index and the richness of fungal communities was as follows: secondary forest > shrubbery > grassland > primary forest. The results suggest that the fungal communities have been greatly changed via vegetation successions, but the diversity index and the richness of the bacterial communities have not been seriously affected. The results provide scientific basis for understanding karst surface ecosystem, which contributes to the future aim of protecting the karst from desertification.

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Variation of Microbial Communities in Aquatic Sediments under Long-Term Exposure to Decabromodiphenyl Ether and UVA Irradiation

Sustainability ◽

10.3390/su11143773 ◽

2019 ◽

Vol 11 (14) ◽

pp. 3773 ◽

Cited By ~ 2

Author(s):

Yi-Tang Chang ◽

Hsi-Ling Chou ◽

Hui Li ◽

Stephen Boyd

Keyword(s):

Bacterial Community ◽

Bacterial Communities ◽

Bacterial Species ◽

Community Diversity ◽

High Dose ◽

Decabromodiphenyl Ether ◽

Uva Irradiation ◽

Different Types ◽

Bde 209

Abiotic components create different types of environmental stress on bacterial communities in aquatic ecosystems. In this study, the long-term exposure to various abiotic factors, namely a high-dose of the toxic chemical decabromodiphenyl ether (BDE-209), continuous UVA irradiation, and different types of sediment, were evaluated in order to assess their influence on the bacterial community. The dominant bacterial community in a single stress situation, i.e., exposure to BDE-209 include members of Comamonadaceae, members of Xanthomonadaceae, a Pseudomonas sp. and a Hydrogenophaga sp. Such bacteria are capable of biodegrading polybrominated diphenyl ethers (PBDEs). When multiple environmental stresses were present, Acidobacteria bacterium and a Terrimonas sp. were predominant, which equipped the population with multiple physiological characteristics that made it capable of both PBDE biodegradation and resistance to UVA irradiation. Methloversatilis sp. and Flavisolibacter sp. were identified as representative genera in this population that were radioresistant. In addition to the above, sediment heterogeneity is also able to alter bacterial community diversity. In total, seventeen species of bacteria were identified in the microcosms containing more clay particles and higher levels of soil organic matter (SOM). This means that these communities are more diverse than in microcosms that contained more sand particles and a lower SOM, which were found to have only twelve identifiable bacterial species. This is the first report to evaluate how changes in bacterial communities in aquatic sediment are affected by the presence of multiple variable environmental factors at the same time.

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Hydrogeology of the Karst Area of the Grassano and Telese Springs

Acque Sotterranee-Italian Journal of Groundwater ◽

10.7343/as-2019-415 ◽

2019 ◽

Author(s):

Guido Leone ◽

Mauro Pagnozzi ◽

Vittorio Catani ◽

Giovanni Testa ◽

Libera Esposito ◽

...

Keyword(s):

Groundwater Flow ◽

Southern Italy ◽

Flow System ◽

Alluvial Plain ◽

Discharge Zone ◽

Karst Area ◽

General Phenomenon ◽

Different Types ◽

Time Fluctuation ◽

Geomorphic Processes

This work deals with the hydraulic phenomenon of the ascendant groundwater flow affecting the karst area of the Grassano and Telese springs (Campania, Southern Italy). It has been investigated through piezometric measurements, discharge and chemical-physical monitoring of springs and measurements of the radon 222Rn activity. The presence of ascendant flows is supported by numerous and different types of evidences in the area: location and topographical position of the springs; amazing density of sinkholes connected to geomorphic processes that develop below the topographic surface and involve the rising of CO2 and H2S rich waters; constancy of the temperature and the electrical conductivity of the spring waters over the time; fluctuation of the radon activity during the hydrological year; increasing of the hydraulic head with depth; presence of artesian conditions in the alluvial plain. Numerical simulations of the groundwater flow also support the general phenomenon of the ascendant flow in the discharge area and represent a useful background to interpret hydrological phenomena in the study area. The results of the simulations are suitable with all the hydrogeological processes observed in the area of the Grassano and Telese springs; this last is thought to belong to the regional groundwater flow system of the Matese massif and represents its discharge zone.

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Karst evolution, hydrocarbon and geothermal resources in flow system context (South Hungary)

10.5194/egusphere-egu21-14896 ◽

2021 ◽

Author(s):

Katalin Csondor ◽

Lehel Csobaji ◽

Brigitta Zentai-Czauner ◽

Orsolya Győri ◽

Anita Erőss

Keyword(s):

Fluid Flow ◽

Flow System ◽

Water Discharge ◽

Regional Scale ◽

Local Scale ◽

Karst Area ◽

Flow Conditions ◽

Regional Flow ◽

Basin Scale ◽

Flow Systems

<p>In South Transdanubia (Hungary) there are remarkable geothermal and hydrocarbon resources. The area is also characterized by natural thermal water discharge at the boundary of outcropping carbonate hills and adjacent sedimentary basin. These regional discharge areas are favourable sites of hypogenic caves as well. These geofluid systems and groundwater related phenomena are usually investigated separately and their interactions are just neglected. The aim of this study is to give all these groundwater-related resources and phenomena a common framework applying the concept of regional hydraulic continuity, and to complete the basin-scale hydraulic assessment of the area based on preproduction archival measured data. Pressure-elevation profiles, tomographic fluid-potential maps and hydraulic cross-sections were constructed to determine the vertical and horizontal fluid-flow conditions. As a result, two kinds of fluid flow systems could be identified. Within the gravitational flow systems, horizontal flow conditions are dominant and the regional flow direction tends toward the S&#8211;SE. In deeper basin regions, an overpressured flow system is prevalent, where fluids are driven laterally from the deeper sub-basins towards their margins. Based on the regional-scale evaluation of fluid flow systems, conclusions could be drawn regarding the geothermal and hydrocarbon potential of the area. Additionally, local-scale phenomena could be explained, and the study emphasizes that knowledge on regional groundwater flow systems is essential to understand local scale groundwater-related phenomena such as recent cave formation in an area. A comparison with the marginal Buda Thermal Karst area allows for generalized conclusions regarding the connections between marginal karst reservoirs and the Pannonian Basin. Furthermore, the results of the study can be directly applied in the exploration and sustainable utilization of groundwater related resources, such as thermal waters and hydrocarbons.</p><p>This topic is part of a project that has received funding from the European Union&#8217;s Horizon 2020 research and innovation programme under grant agreement No 810980. The National Research, Development and Innovation Fund has provided financial support to the research under the grant agreement no. PD 116227.</p>

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Assessment of viral assemblages in different types of wetland water in northeast China using RAPD-PCR

Aquatic Microbial Ecology ◽

10.3354/ame01952 ◽

2020 ◽

Vol 85 ◽

pp. 183-196

Author(s):

Y Sun ◽

J Liu ◽

Q Yao ◽

J Jin ◽

X Liu ◽

...

Keyword(s):

Bacterial Community ◽

Water Samples ◽

Northeast China ◽

Bacterial Community Composition ◽

Freshwater Wetlands ◽

Viral Community ◽

Rapd Pcr ◽

Wetland Water ◽

Different Types ◽

Viral Communities

Viruses are the most abundant and ubiquitous biological entities in various ecosystems, yet few investigations of viral communities in wetlands have been performed. To address this data gap, water samples from 6 wetlands were randomly collected across northeast China; viruses in the water were concentrated by sequential tangential flow filtration, and viral communities were assessed through randomly amplified polymorphic DNA-PCR (RAPD-PCR) with 4 decamer oligonucleotide primers. Principal coordinate analysis and hierarchical clustering analysis of the DNA fingerprints showed that viral community compositions differed among the water samples: communities in the 2 coastal wetlands were more similar to each other than to those in the 4 freshwater wetlands. The Shannon-Weaver index (H) and evenness index (E) of the RAPD-PCR fingerprint also differed among the 6 wetlands. Mantel test revealed that the changes in viral communities in wetland water were most closely related to the water NH4+-N and inorganic C content, followed by total K, P, C and NO3--N. DNA sequence analysis of the excised bands revealed that viruses accounted for ~40% of all sequences. Among the hit viral homologs, the majority belonged to the Microviridae. Moreover, variance partitioning analysis showed that the viral community contributed 24.58% while environmental factors explained 30.56% of the bacterial community variation, indicating that the bacterial community composition was strongly affected by both viral community and water variables. This work provides an initial outline of the viral communities from different types of wetlands in northeast China and improves our understanding of the viral diversity in these ecosystems.

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Enumeration of Cryptosporidium oocysts from surface water concentrates by laser-scanning cytometry

Water Science & Technology ◽

10.2166/wst.2000.0133 ◽

2000 ◽

Vol 41 (7) ◽

pp. 197-202 ◽

Cited By ~ 6

Author(s):

F. Zanelli ◽

B. Compagnon ◽

J. C. Joret ◽

M. R. de Roubin

Keyword(s):

Surface Water ◽

Water Samples ◽

Laser Scanning ◽

Immunomagnetic Separation ◽

Entire Surface ◽

Cryptosporidium Oocysts ◽

Different Types ◽

Laser Scanning Cytometry ◽

Direct Microscopic Observation

The utilization of the ChemScan® RDI was tested for different types of water concentrates. Concentrates were prepared by cartridge filtration or flocculation, and analysed either without purification, or after Immunomagnetic separation (IMS) or flotation on percoll-sucrose gradients. Theenumeration of the oocysts was subsequently performed using the ChemScan® RDI Cryptosporidium application. Enumeration by direct microscopic observation of the entire surface of the membrane was carried out as a control, and recoveries were calculated as a ratio between the ChemScan® RDI result and the result obtained with direct microscopic enumeration. The Chemscan enumeration technique proved reliable, with recoveries yielding close to 100% in most cases (average 125%, range from 86 to 467%) for all the concentration/purification techniques tested. The quality of the antibodies was shown to be critical, with antibodies from some suppliers yielding recoveries a low as 10% in some cases. This difficulty could, however, be overcome by the utilization of the antibody provided by Chemunex. These data conclusively prove that laser scanning cytometry, which greatly facilitates the microscopic enumeration of Cryptosporidium oocysts from water samples and decreases the time of observation by four to six times, can be successfully applied to water concentrates prepared from a variety of concentration/purification techniques.

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Bacterial diversity and predicted enzymatic function in a multipurpose surface water system – from wastewater effluent discharges to drinking water production

Environmental Microbiome ◽

10.1186/s40793-021-00379-w ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Ananda Tiwari ◽

Anna-Maria Hokajärvi ◽

Jorge Santo Domingo ◽

Michael Elk ◽

Balamuralikrishna Jayaprakash ◽

...

Keyword(s):

Drinking Water ◽

Surface Water ◽

Bacterial Community ◽

Human Health ◽

Bacterial Diversity ◽

Water Samples ◽

Bacterial Communities ◽

Treatment Process ◽

Pollution Sources ◽

Production Well

Abstract Background Rivers and lakes are used for multiple purposes such as for drinking water (DW) production, recreation, and as recipients of wastewater from various sources. The deterioration of surface water quality with wastewater is well-known, but less is known about the bacterial community dynamics in the affected surface waters. Understanding the bacterial community characteristics —from the source of contamination, through the watershed to the DW production process—may help safeguard human health and the environment. Results The spatial and seasonal dynamics of bacterial communities, their predicted functions, and potential health-related bacterial (PHRB) reads within the Kokemäenjoki River watershed in southwest Finland were analyzed with the 16S rRNA-gene amplicon sequencing method. Water samples were collected from various sampling points of the watershed, from its major pollution sources (sewage influent and effluent, industrial effluent, mine runoff) and different stages of the DW treatment process (pre-treatment, groundwater observation well, DW production well) by using the river water as raw water with an artificial groundwater recharge (AGR). The beta-diversity analysis revealed that bacterial communities were highly varied among sample groups (R = 0.92, p < 0.001, ANOSIM). The species richness and evenness indices were highest in surface water (Chao1; 920 ± 10) among sample groups and gradually decreased during the DW treatment process (DW production well; Chao1: 320 ± 20). Although the phylum Proteobacteria was omnipresent, its relative abundance was higher in sewage and industrial effluents (66–80%) than in surface water (55%). Phyla Firmicutes and Fusobacteria were only detected in sewage samples. Actinobacteria was more abundant in the surface water (≥13%) than in other groups (≤3%). Acidobacteria was more abundant in the DW treatment process (≥13%) than in others (≤2%). In total, the share of PHRB reads was higher in sewage and surface water than in the DW treatment samples. The seasonal effect in bacterial communities was observed only on surface water samples, with the lowest diversity during summer. Conclusions The low bacterial diversity and absence of PHRB read in the DW samples indicate AGR can produce biologically stable and microbiologically safe drinking water. Furthermore, the significantly different bacterial communities at the pollution sources compared to surface water and DW samples highlight the importance of effective wastewater treatment for protecting the environment and human health.

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Spatiotemporal variations and relationships of phosphorus, phosphomonoesterases, and bacterial communities in sediments from two Chilean rivers

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.145782 ◽

2021 ◽

pp. 145782

Author(s):

Marco Campos ◽

Joaquin I. Rilling ◽

Jacquelinne J. Acuña ◽

Tamara Valenzuela ◽

Giovanni Larama ◽

...

Keyword(s):

Bacterial Communities ◽

Spatiotemporal Variations

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Integration of culture-dependent and independent methods provides a more coherent picture of the pig gut microbiome

FEMS Microbiology Ecology ◽

10.1093/femsec/fiaa022 ◽

2020 ◽

Vol 96 (3) ◽

Cited By ~ 2

Author(s):

Gavin J Fenske ◽

Sudeep Ghimire ◽

Linto Antony ◽

Jane Christopher-Hennings ◽

Joy Scaria

Keyword(s):

Bacterial Communities ◽

Bacterial Species ◽

Shotgun Metagenomics ◽

Culture Techniques ◽

Microbiome Composition ◽

Culture Independent ◽

Health And Disease ◽

The Media ◽

And Function ◽

Culture Dependent

ABSTRACT Bacterial communities resident in the hindgut of pigs, have profound impacts on health and disease. Investigations into the pig microbiome have utilized either culture-dependent, or far more commonly, culture-independent techniques using next generation sequencing. We contend that a combination of both approaches generates a more coherent view of microbiome composition. In this study, we surveyed the microbiome of Tamworth breed and feral pigs through the integration high throughput culturing and shotgun metagenomics. A single culture medium was used for culturing. Selective screens were added to the media to increase culture diversity. In total, 46 distinct bacterial species were isolated from the Tamworth and feral samples. Selective screens successfully shifted the diversity of bacteria on agar plates. Tamworth pigs are highly dominated by Bacteroidetes primarily composed of the genus Prevotella whereas feral samples were more diverse with almost equal proportions of Firmicutes and Bacteroidetes. The combination of metagenomics and culture techniques facilitated a greater retrieval of annotated genes than either method alone. The single medium based pig microbiota library we report is a resource to better understand pig gut microbial ecology and function. It allows for assemblage of defined bacterial communities for studies in bioreactors or germfree animal models.

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