scholarly journals The total and active bacterial community of the chlorolichen Cetraria islandica and its response to long-term warming in sub-Arctic tundra

2020 ◽  
Author(s):  
Ingeborg J. Klarenberg ◽  
Christoph Keuschnig ◽  
Denis Warshan ◽  
Ingibjörg Svala Jónsdóttir ◽  
Oddur Vilhelmsson
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Relative Abundance ◽  
Environmental Conditions ◽  
Bacterial Community Composition ◽  
Arctic Tundra ◽  
Amplicon Sequencing ◽  
Total Community ◽  
First Time

AbstractLichens are traditionally defined as a symbiosis between a fungus and a green alga and or a cyanobacterium. This idea has been challenged by the discovery of bacterial communities inhabiting the lichen thalli. These bacteria are thought to contribute to the survival of lichens under extreme and changing environmental conditions. How these changing environmental conditions affect the lichen-associated bacterial community composition remains unclear.We describe the total (rDNA-based) and potentially metabolically active (rRNA-based) bacterial community of the lichen Cetaria islandica and its response to long-term warming using a 20-year warming experiment in an Icelandic sub-Arctic tundra. 16S rRNA and rDNA amplicon sequencing showed that the orders Acetobacterales (of the class Alphaproteobacteria) and Acidobacteriales (of the phylum Acidobacteria) dominated the bacterial community. Numerous ASVs (amplicon sequence variants) taxa could only be detected in the potentially active community but not in the total community. Long-term warming led to increases in relative abundance on class, order and ASV level. Warming altered the relative abundance of ASVs of the most common bacterial genera, such as Granulicella and Endobacter. The potentially metabolically active bacterial community was also more responsive to warming than the total community.Our results suggest that the bacterial community of the lichen C. islandica is dominated by acidophilic taxa and harbors disproportionally active rare taxa. We also show for the first time that climate warming can lead to shifts in lichen-associated bacterial community composition.

scholarly journals The Total and Active Bacterial Community of the Chlorolichen Cetraria islandica and Its Response to Long-Term Warming in Sub-Arctic Tundra

2020 ◽  
Vol 11 ◽  
Author(s):  
Ingeborg J. Klarenberg ◽  
Christoph Keuschnig ◽  
Denis Warshan ◽  
Ingibjörg Svala Jónsdóttir ◽  
Oddur Vilhelmsson
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Relative Abundance ◽  
Environmental Conditions ◽  
Bacterial Community Composition ◽  
Arctic Tundra ◽  
Amplicon Sequencing ◽  
Total Community ◽  
First Time

Lichens are traditionally defined as a symbiosis between a fungus and a green alga and or a cyanobacterium. This idea has been challenged by the discovery of bacterial communities inhabiting the lichen thalli. These bacteria are thought to contribute to the survival of lichens under extreme and changing environmental conditions. How these changing environmental conditions affect the lichen-associated bacterial community composition remains unclear. We describe the total (rDNA-based) and potentially metabolically active (rRNA-based) bacterial community of the lichen Cetaria islandica and its response to long-term warming using a 20-year warming experiment in an Icelandic sub-Arctic tundra. 16S rRNA and rDNA amplicon sequencing showed that the orders Acetobacterales (of the class Alphaproteobacteria) and Acidobacteriales (of the phylum Acidobacteria) dominated the bacterial community. Numerous amplicon sequence variants (ASVs) could only be detected in the potentially active community but not in the total community. Long-term warming led to increases in relative abundance of bacterial taxa on class, order and ASV level. Warming altered the relative abundance of ASVs of the most common bacterial genera, such as Granulicella and Endobacter. The potentially metabolically active bacterial community was also more responsive to warming than the total community. Our results suggest that the bacterial community of the lichen C. islandica is dominated by acidophilic taxa and harbors disproportionally active rare taxa. We also show for the first time that climate warming can lead to shifts in lichen-associated bacterial community composition.

Soil fertility and bacterial community composition in a semiarid Mediterranean agricultural soil under long‐term tillage management

2020 ◽  
Vol 36 (4) ◽  
pp. 604-615
Author(s):  
Mohammad Yaghoubi Khanghahi ◽  
Giovanna Cucci ◽  
Giovanni Lacolla ◽  
Loredana Lanzellotti ◽  
Carmine Crecchio
Keyword(s):  
Bacterial Community ◽  
Soil Fertility ◽  
Community Composition ◽  
Agricultural Soil ◽  
Bacterial Community Composition

scholarly journals Activity and Composition of the Denitrifying Bacterial Community Respond Differently to Long-Term Fertilization

2005 ◽  
Vol 71 (12) ◽  
pp. 8335-8343 ◽  
Author(s):  
Karin Enwall ◽  
Laurent Philippot ◽  
Sara Hallin
Keyword(s):  
Sewage Sludge ◽  
Bacterial Community ◽  
Soil Respiration ◽  
Community Composition ◽  
Bacterial Community Composition ◽  
Arable Soil ◽  
Functional Markers ◽  
Potential Denitrification ◽  
Basal Soil Respiration

ABSTRACT The objective of this study was to explore the long-term effects of different organic and inorganic fertilizers on activity and composition of the denitrifying and total bacterial communities in arable soil. Soil from the following six treatments was analyzed in an experimental field site established in 1956: cattle manure, sewage sludge, Ca(NO3)2, (NH4)2SO4, and unfertilized and unfertilized bare fallow. All plots but the fallow were planted with corn. The activity was measured in terms of potential denitrification rate and basal soil respiration. The nosZ and narG genes were used as functional markers of the denitrifying community, and the composition was analyzed using denaturing gradient gel electrophoresis of nosZ and restriction fragment length polymorphism of narG, together with cloning and sequencing. A fingerprint of the total bacterial community was assessed by ribosomal intergenic spacer region analysis (RISA). The potential denitrification rates were higher in plots treated with organic fertilizer than in those with only mineral fertilizer. The basal soil respiration rates were positively correlated to soil carbon content, and the highest rates were found in the plots with the addition of sewage sludge. Fingerprints of the nosZ and narG genes, as well as the RISA, showed significant differences in the corresponding communities in the plots treated with (NH4)2SO4 and sewage sludge, which exhibited the lowest pH. In contrast, similar patterns were observed among the other four treatments, unfertilized plots with and without crops and the plots treated with Ca(NO3)2 or with manure. This study shows that the addition of different fertilizers affects both the activity and the composition of the denitrifying communities in arable soil on a long-term basis. However, the treatments in which the denitrifying and bacterial community composition differed the most did not correspond to treatments with the most different activities, showing that potential activity was uncoupled to community composition.

The effect of long-term nitrate treatment on SRB activity, corrosion rate and bacterial community composition in offshore water injection systems

2008 ◽  
Vol 35 (12) ◽  
pp. 1625-1636 ◽  
Author(s):  
Gunhild Bødtker ◽  
Tore Thorstenson ◽  
Bente-Lise P. Lillebø ◽  
Bente E. Thorbjørnsen ◽  
Rikke Helen Ulvøen ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Corrosion Rate ◽  
Community Composition ◽  
Bacterial Community Composition ◽  
Water Injection ◽  
Offshore Water ◽  
Nitrate Treatment

scholarly journals Direct and context-dependent effects of light, temperature, and phytoplankton shape bacterial community composition

2016 ◽  
Author(s):  
Sara F. Paver ◽  
Angela D. Kent
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Environmental Conditions ◽  
Species Interactions ◽  
Bacterial Community Composition ◽  
Humic Lakes ◽  
Phytoplankton Assemblages ◽  
Mediated Effects ◽  
Light Surface ◽  
Influence Of Temperature On

AbstractSpecies interactions, environmental conditions, and stochastic processes work in concert to bring about changes in community structure. However, the relative importance of specific factors and how their combined influence affects community composition remain largely unclear. We conducted a multi-factorial experiment to 1) disentangle the direct and interaction-mediated effects of environmental conditions and 2) augment our understanding of how environmental context modulates species interactions. We focus on a planktonic system where interactions with phytoplankton effect changes in the composition of bacterial communities, and light and temperature conditions can influence bacteria directly as well as through their interactions with phytoplankton. Epilimnetic bacteria from two humic lakes were combined with phytoplankton assemblages from each lake (“home” or “away”) or a no-phytoplankton control and incubated for 5 days under all combinations of light (surface, ∼25% surface irradiance) and temperature (5 levels from 10°C to 25°C). Observed light effects were primarily direct while phytoplankton and temperature effects on bacterial community composition were highly interdependent. The influence of temperature on aquatic bacteria was consistently mediated by phytoplankton and most pronounced for bacteria incubated with “away” phytoplankton treatments, likely due to the availability of novel phytoplankton-derived resources. The effects of phytoplankton on bacterial community composition were generally increased at higher temperatures. Incorporating mechanisms underlying the observed interdependent effects of species interactions and environmental conditions into modeling frameworks may improve our ability to forecast ecological responses to environmental change.

scholarly journals Assessing the microbiota of recycled bedding sand on a Wisconsin dairy farm

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Hannah E. Pilch ◽  
Andrew J. Steinberger ◽  
Donald C. Sockett ◽  
Nicole Aulik ◽  
Garret Suen ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Pathogenic Bacteria ◽  
Bacterial Community Composition ◽  
Dairy Farm ◽  
Amplicon Sequencing ◽  
Rrna Gene ◽  
Recycling System ◽  
Core Microbiota ◽  
Relative Abundances

Abstract Background Sand is often considered the preferred bedding material for dairy cows as it is thought to have lower bacterial counts than organic bedding materials and cows bedded on sand experience fewer cases of lameness and disease. Sand can also be efficiently recycled and reused, making it cost-effective. However, some studies have suggested that the residual organic material present in recycled sand can serve as a reservoir for commensal and pathogenic bacteria, although no studies have yet characterized the total bacterial community composition. Here we sought to characterize the bacterial community composition of a Wisconsin dairy farm bedding sand recycling system and its dynamics across several stages of the recycling process during both summer and winter using 16S rRNA gene amplicon sequencing. Results Bacterial community compositions of the sand recycling system differed by both seasons and stage. Summer samples had higher richness and distinct community compositions, relative to winter samples. In both summer and winter samples, the diversity of recycled sand decreased with time drying in the recycling room. Compositionally, summer sand 14 d post-recycling was enriched in operational taxonomic units (OTUs) belonging to the genera Acinetobacter and Pseudomonas, relative to freshly washed sand and sand from cow pens. In contrast, no OTUs were found to be enriched in winter sand. The sand recycling system contained an overall core microbiota of 141 OTUs representing 68.45% ± 10.33% SD of the total bacterial relative abundance at each sampled stage. The 4 most abundant genera in this core microbiota included Acinetobacter, Psychrobacter, Corynebacterium, and Pseudomonas. Acinetobacter was present in greater abundance in summer samples, whereas Psychrobacter and Corynebacterium had higher relative abundances in winter samples. Pseudomonas had consistent relative abundances across both seasons. Conclusions These findings highlight the potential of recycled bedding sand as a bacterial reservoir that warrants further study.

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