Species sorting and neutral processes are both important during the initial assembly of bacterial communities

<p>Bacterial communities are essential to the biogeochemical cycle in riverine ecosystems. However, the integrated biogeography and assembly process of planktonic and sedimentary bacterial communities in large rivers is still poorly understood. Here, the study provided the spatiotemporal pattern of bacterial communities in the Yangtze River of 4300 km continuum, which is the largest river in Asia. We found that the taxa in sediments are the main contributors to the bacterial diversity of the river ecosystem since sediments sub-group took 98.8% of the total 38, 904 Operational Taxonomic Units (OTUs) observed in 280 samples. Seasonal differences in bacterial communities were statistically significant in water, whereas bacterial communities in both water and sediment were geographically clustered according to five types of landforms: mountain, foothill, basin, foothill-mountain, and plain. Interestingly, the presence of two huge dams resulted in a drastic fall of bacterial taxa in sediment immediately downstream due to severe riverbed scouring. The integrity of the biogeography was satisfactorily interpreted by the combination of neutral and species sorting perspectives in meta-community theory for bacterial communities in flowing water and sediment. Although deterministic process had dominant influence on assembly processes in water and sediment communities, homogeneous selection was the main contributor in water, while combination of homogeneous selection and variable selection contributed selection process in sediment. In addition, homogenizing dispersal played more important role in community assembly process in sediment than water. Our study fills a gap in understanding of biogeography and assembly process of bacterial communities in one of the world&#8217;s largest river and highlights the importance of both planktonic and sedimentary communities to the integrity of bacterial biogeographic patterns in a river subject to varying natural and anthropogenic impacts.</p>

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Species sorting and seasonal dynamics primarily shape bacterial communities in the Upper Mississippi River

The Science of The Total Environment ◽

10.1016/j.scitotenv.2014.10.012 ◽

2015 ◽

Vol 505 ◽

pp. 435-445 ◽

Cited By ~ 82

Author(s):

Christopher Staley ◽

Trevor J. Gould ◽

Ping Wang ◽

Jane Phillips ◽

James B. Cotner ◽

...

Keyword(s):

Mississippi River ◽

Seasonal Dynamics ◽

Bacterial Communities ◽

Upper Mississippi River ◽

Species Sorting

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Turnover is replaced by nestedness with increasing geographical distance in bacterial communities of coastal shallow lakes

Marine and Freshwater Research ◽

10.1071/mf19110 ◽

2020 ◽

Vol 71 (9) ◽

pp. 1086

Author(s):

Marla Sonaira Lima ◽

Fabiana Schneck ◽

Ng Haig They ◽

Luciane Oliveira Crossetti ◽

Juliana Elisa Bohnenberger ◽

...

Keyword(s):

Shallow Lakes ◽

Bacterial Communities ◽

Local Environment ◽

Dispersal Limitation ◽

Geographical Distance ◽

Environmental Filters ◽

Species Sorting ◽

Relative Contribution ◽

Β Diversity ◽

The Relationship

In this study we measured the relative contribution of two components of β-diversity, turnover and nestedness, of bacterioplankton among 25 shallow lakes in southern Brazil and tested their relationship with local (environment, chlorophyll-a and biomass of phytoplanktonic classes) and landscape variables, as well as geographical distance. We predicted that turnover would be the largest share of total β-diversity due to the variation of local characteristics among lakes. Further, we expected nestedness to increase at the expense of turnover with increasing geographical distance among lakes due to dispersal limitation. The results indicated a higher contribution of turnover than nestedness to total β-diversity, which was driven by local factors. When the relationship between β-diversity components and the spatial extent between each lake and all other lakes was considered, turnover was replaced by nestedness with increasing geographical distance for 8 (the furthermost lakes) of the 25 lakes likely because of a combination of decreasing dispersal due to distance and richness differences due to wind-driven mass effects. The results of this study suggest a role for nestedness as an indicator of dispersal limitation owing to geographical distance and wind dispersal, and for turnover as an indicator of species sorting because of environmental filters for these freshwater bacterial communities.

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Partition among niche and neutral explanations for metacommunity patterns of fish from Cerrado streams

10.22541/au.164214661.19792299/v1 ◽

2022 ◽

Author(s):

Thiago Bernardi Vieira ◽

Liriann Chrisley Da Silva ◽

Jessica Silva ◽

Lilian Casatti ◽

Renato de Romero ◽

...

Keyword(s):

Neutral Theory ◽

Fish Communities ◽

Fish Fauna ◽

Mass Effect ◽

Species Selection ◽

Catchment Basin ◽

Species Sorting ◽

Neutral Processes ◽

Landscape Unit ◽

Metacommunity Structure

The Species-Sorting concept, one of the models developed to explain patterns in metacommunity structure, suggests that relationships between biological communities and environmental conditions is the basic means of the species selection processes. A second concept is Neutral Theory, and the idea of neutral dynamics underpinning metacommunity structure, cannot be overlooked. The third mechanism is the Mass-Effect concept, that focuses on the interaction between environmental condition and neutral effects. In the present study, we partitioned fish communities in streams between niche and neutral theory concepts, identifying the best representation of metacommunity structure, and assessed if linear and hydrographic distance were equivalent in the representation of neutral processes. The result points to the importance of species sorting mechanisms in structuring fish communities with neutral processes best represented by the linear distances. These results are important for the fish fauna conservation leading to three considerations: (i) the variation of the landscape and habitat is important for the stream fish, (ii) the natural barriers are an important landscape component to be considered, and (iii) the artificial barriers (dams and impoundments) need to be planned taking in account the catchment basin as the landscape unit.

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Linked networks reveal dual roles of insect dispersal and species sorting for bacterial communities in flowers

10.1101/847376 ◽

2019 ◽

Cited By ~ 3

Author(s):

Ash T. Zemenick ◽

Rachel L. Vannette ◽

Jay A. Rosenheim

Keyword(s):

Plant Species ◽

Community Assembly ◽

Bacterial Communities ◽

Structural Features ◽

Relative Importance ◽

Dispersal Rate ◽

Dual Roles ◽

Species Sorting ◽

Insect Dispersal ◽

Microbial Community Assembly

AbstractDue to the difficulty of tracking microbial dispersal, it rarely possible to disentangle the relative importance of dispersal and species sorting for microbial community assembly. Here, we leverage a detailed multilevel network to examine drivers of bacterial community assembly within flowers. We show that plant species with similar visitor communities tend to have similar bacterial communities, and visitor identity to be more important than dispersal rate in structuring floral bacterial communities. However, plants occupied divergent positions in plant-insect and plant-microbe networks, suggesting an important role for species sorting. Taken together, our analyses suggest dispersal is important in determining similarity in microbial communities across plant species, but not as important in determining structural features of the floral bacterial network. A multilevel network approach thus allows us to address features of community assembly that cannot be considered when viewing networks as separate entities.

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