Stochastic processes shape the bacterial community assembly in shrimp cultural pond sediments

Abstract Bacterial communities in wastewater treatment plants (WWTPs) affect plant functionality through their role in the removal of pollutants from wastewater. Bacterial communities vary extensively based on plant operating conditions and influent characteristics. The capacity of WWTPs can also affect the bacterial community via variations in the organic or nutrient composition of the influent. Despite the importance considering capacity, the characteristics that control bacterial community assembly are largely unknown. In this study, we discovered that bacterial communities in WWTPs in Korea and Vietnam, which differ remarkably in capacity, exhibit unique structures and interactions that are governed mainly by the capacity of WWTPs. Bacterial communities were analysed using 16S rRNA gene sequencing and exhibited clear differences between the two regions, with these differences being most pronounced in activated sludge. We found that capacity contributed the most to bacterial interactions and community structure, whereas other factors had less impact. Co-occurrence network analysis showed that microorganisms from high-capacity WWTPs are more interrelated than those from low-capacity WWTPs, which corresponds to the tighter clustering of bacterial communities in Korea. These results will contribute to the understanding of bacterial community assembly in activated sludge processing.

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Thermodynamically favorable reactions shape the archaeal community affecting bacterial community assembly in oil reservoirs

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.146506 ◽

2021 ◽

pp. 146506

Author(s):

Jie-Yu Zhao ◽

Bing Hu ◽

Jan Dolfing ◽

Yan Li ◽

Yue-Qin Tang ◽

...

Keyword(s):

Bacterial Community ◽

Community Assembly ◽

Archaeal Community ◽

Oil Reservoirs

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Bacterial community assembly and antibiotic resistance genes in the lettuce-soil system upon antibiotic exposure

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.146255 ◽

2021 ◽

Vol 778 ◽

pp. 146255

Author(s):

Yike Shen ◽

Elliot T. Ryser ◽

Hui Li ◽

Wei Zhang

Keyword(s):

Antibiotic Resistance ◽

Bacterial Community ◽

Resistance Genes ◽

Community Assembly ◽

Antibiotic Resistance Genes ◽

Antibiotic Exposure ◽

Soil System

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Phylogenetic and Functional Traits Verify the Combined Effect of Deterministic and Stochastic Processes in the Community Assembly of Temperate Forests along an Elevational Gradient

Forests ◽

10.3390/f12050591 ◽

2021 ◽

Vol 12 (5) ◽

pp. 591

Author(s):

Wensong Zhou ◽

Yuxin Zhang ◽

Shuang Zhang ◽

Basil N. Yakimov ◽

Keming Ma

Keyword(s):

Stochastic Processes ◽

Functional Traits ◽

Community Assembly ◽

Woody Plants ◽

Elevational Gradient ◽

Combined Effect ◽

Abiotic Environment ◽

Spatial Factors ◽

Assembly Mechanism ◽

Deterministic Processes

Explaining community assembly mechanisms along elevational gradients dominated by deterministic processes or stochastic processes is a pressing challenge. Many studies suggest that phylogenetic and functional diversity are significant indicators of the process. In this study, we analyzed the structure and beta diversity of phylogenetic and functional traits along an elevational gradient and discussed the effects of environmental and spatial factors. We found that the phylogenetic and functional traits showed inconsistent changes, and their variations were closely related to the abiotic environment. The results suggested that the community assembly of woody plants was obviously affected by the combined effect of deterministic processes and the stochastic hypothesis (primarily by the latter). Phylogenetic and functional traits had a certain relationship but changed according to different rules. These results enhance our understanding of the assembly mechanism of forest communities by considering both phylogenetic and functional traits.

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Bacterial Community Dynamics in Full-Scale Activated Sludge Bioreactors: Operational and Ecological Factors Driving Community Assembly and Performance

PLoS ONE ◽

10.1371/journal.pone.0042524 ◽

2012 ◽

Vol 7 (8) ◽

pp. e42524 ◽

Cited By ~ 68

Author(s):

Alexis Valentín-Vargas ◽

Gladys Toro-Labrador ◽

Arturo A. Massol-Deyá

Keyword(s):

Bacterial Community ◽

Activated Sludge ◽

Community Assembly ◽

Community Dynamics ◽

Ecological Factors ◽

Full Scale ◽

Bacterial Community Dynamics ◽

And Performance

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Deterministic Selection Dominates Microbial Community Assembly in Termite Mounds Across a Large Spatial Area

10.21203/rs.3.rs-34782/v1 ◽

2020 ◽

Author(s):

Qing-Lin Chen ◽

Hang-Wei Hu ◽

Zhen-Zhen Yan ◽

Chao-Yu Li ◽

Bao-Anh Thi Nguyen ◽

...

Keyword(s):

Microbial Community ◽

Stochastic Processes ◽

Microbial Communities ◽

Fungal Community ◽

Community Assembly ◽

Distance Decay ◽

Termite Mounds ◽

Deterministic Processes ◽

Microbial Community Assembly

Abstract Background: Termites are ubiquitous insects in tropical and subtropical habitats, where they construct massive mounds from soil, their saliva and excreta. Termite mounds harbor an enormous amount of microbial inhabitants, which regulate multiple ecosystem functions such as mitigating methane emissions and increasing ecosystem resistance to climate change. However, we lack a mechanistic understanding about the role of termite mounds in modulating the microbial community assembly processes, which are essential to unravel the biological interactions of soil fauna and microorganisms, the major components of soil food webs. We conducted a large-scale survey across a >1500 km transect in northern Australia to investigate biogeographical patterns of bacterial and fungal community in 134 termite mounds and the relative importance of deterministic versus stochastic processes in microbial community assembly. Results: Microbial alpha (number of phylotypes) and beta (changes in bacterial and fungal community composition) significantly differed between termite mounds and surrounding soils. Microbial communities in termite mounds exhibited a significant distance-decay pattern, and fungal communities had a stronger distance-decay relationship (slope = -1.91) than bacteria (slope = -0.21). Based on the neutral community model (fitness < 0.7) and normalized stochasticity ratio index (NST) with a value below the 50% boundary point, deterministic selection, rather than stochastic forces, predominated the microbial community assembly in termite mounds. Deterministic processes exhibited significantly weaker impacts on bacteria (NST = 45.23%) than on fungi (NST = 33.72%), probably due to the wider habitat niche breadth and higher potential migration rate of bacteria. The abundance of antibiotic resistance genes (ARGs) was negatively correlated with bacterial/fungal biomass ratios, indicating that ARG content might be an important biotic factor that drove the biogeographic pattern of microbial communities in termite mounds. Conclusions: Deterministic processes play a more important role than stochastic processes in shaping the microbial community assembly in termite mounds, an unique habitat ubiquitously distributed in tropical and subtropical ecosystems. An improved understanding of the biogeographic patterns of microorganisms in termite mounds is crucial to decipher the role of soil faunal activities in shaping microbial community assembly, with implications for their mediated ecosystems functions and services.

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Phyllosphere community assembly and response to drought stress on common tropical and temperate forage grasses

10.1101/2021.05.10.443535 ◽

2021 ◽

Author(s):

Emily K. Bechtold ◽

Stephanie Ryan ◽

Sarah E. Moughan ◽

Ravi Ranjan ◽

Klaus Nüsslein

Keyword(s):

Microbial Community ◽

Drought Stress ◽

Bacterial Community ◽

Community Assembly ◽

Community Diversity ◽

Grass Species ◽

Severe Drought ◽

Hormone Production ◽

Plant Host ◽

Bacterial Community Diversity

Grasslands represent a critical ecosystem important for global food production, soil carbon storage, and water regulation. Current intensification and expansion practices add to the degradation of grasslands and dramatically increase greenhouse gas emissions and pollution. Thus, new ways to sustain and improve their productivity are needed. Research efforts focus on the plant-leaf microbiome, or phyllosphere, because its microbial members impact ecosystem function by influencing pathogen resistance, plant hormone production, and nutrient availability through processes including nitrogen fixation. However, little is known about grassland phyllospheres and their response to environmental stress. In this study, globally dominant temperate and tropical forage grass species were grown in a greenhouse under current climate conditions and drought conditions that mimic future climate predictions to understand if (i) plant host taxa influence microbial community assembly, (ii) microbial communities respond to drought stress, and (iii) phyllosphere community changes correlate to changes in plant host traits and stress-response strategies. Community analysis using high resolution sequencing revealed Gammaproteobacteria as the dominant bacterial class, which increased under severe drought stress on both temperate and tropical grasses while overall bacterial community diversity declined. Bacterial community diversity, structure, and response to drought were significantly different between grass species. This community dependence on plant host species correlated with differences in grass species traits, which became more defined under drought stress conditions, suggesting symbiotic evolutionary relationships between plant hosts and their associated microbial community. Further understanding these strategies and the functions microbes provide to plants will help us utilize microbes to promote agricultural and ecosystem productivity in the future.

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Aboveground and belowground arthropod communities experience different relative influences of stochastic and deterministic assembly processes following disturbance

10.7287/peerj.preprints.1674v1 ◽

2016 ◽

Author(s):

Scott Ferrenberg ◽

Alexander S. Martinez ◽

Akasha M. Faist

Keyword(s):

Community Structure ◽

Stochastic Processes ◽

Community Assembly ◽

Tree Mortality ◽

Species Turnover ◽

Mineral Soil ◽

Relative Influence ◽

Subalpine Forest ◽

Arthropod Community ◽

Arthropod Communities

Background. Understanding patterns of biodiversity is a longstanding challenge in ecology. Similar to other biotic groups, arthropod community structure can be shaped by deterministic and stochastic processes, with limited understanding of what moderates the relative influence of these processes. Disturbances have been noted to alter the relative influence of deterministic and stochastic processes on community assembly in various study systems, implicating ecological disturbances as a potential moderator of these forces. Methods. Using a disturbance gradient along a 5-year chronosequence of insect-induced tree mortality in a subalpine forest of the southern Rocky Mountains, Colorado, USA, we examined changes in community structure and relative influences of deterministic and stochastic processes in the assembly of aboveground (surface and litter-active species) and belowground (species active in organic and mineral soil layers) arthropod communities. Arthropods were sampled for all years of the chronosequence via pitfall traps (aboveground community) and modified Winkler funnels (belowground community) and sorted to morphospecies. Community structure of both communities were assessed via comparisons of morphospecies diversity and assemblages. Assembly processes were inferred from a mixture of linear models and matrix correlations testing for community associations with environmental properties, and from null-deviation models calculated from observed vs. expected levels of species turnover (Beta diversity) among samples. Results. Tree mortality altered community structure in both aboveground and belowground arthropod communities, but null models suggested that aboveground communities experienced greater relative influences of deterministic processes, while the relative influence of stochastic processes increased for belowground communities. Additionally, Mantel tests and linear regression models revealed significant associations between the aboveground arthropod communities and vegetation and soil properties, but no significant association among belowground arthropod communities and environmental factors. Discussion. Our results suggest context-dependent influences of stochastic and deterministic community assembly processes across different fractions of a ground-dwelling arthropod community following a disturbance. This variation in assembly may be linked to contrasting ecological strategies and dispersal rates within above- and below-ground communities. Our findings add to a growing body of evidence indicating concurrent influences of different processes in community assembly, and highlight the need to consider potential variation across different fractions of biotic communities when testing community ecology theory.

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