scholarly journals Proximate grassland and shrub-encroached sites show dramatic restructuring of soil bacterial communities

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7304
Author(s):  
Xingjia Xiang ◽  
Sean M. Gibbons ◽  
He Li ◽  
Haihua Shen ◽  
Haiyan Chu
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Bacterial Communities ◽  
Vegetation Type ◽  
Bacterial Community Composition ◽  
Shrub Encroachment ◽  
Soil Bacterial Community ◽  
Grassland Soils ◽  
Soil Bacterial Communities ◽  
Soil Bacterial

Background Changes in aboveground community composition and diversity following shrub encroachment have been studied extensively. Recently, shrub encroachment was associated with differences in belowground bacterial communities relative to non-encroached grassland sites hundreds of meters away. This spatial distance between grassland and shrub sites left open the question of how soil bacterial communities associated with different vegetation types might differ within the same plot location. Methods We examined soil bacterial communities between shrub-encroached and adjacent (one m apart) grassland soils in Chinese Inner Mongolian, using high-throughput sequencing method (Illumina, San Diego, CA, USA). Results Shrub-encroached sites were associated with dramatic restructuring of soil bacterial community composition and predicted metabolic function, with significant increase in bacterial alpha-diversity. Moreover, bacterial phylogenic structures showed clustering in both shrub-encroached and grassland soils, suggesting that each vegetation type was associated with a unique and defined bacterial community by niche filtering. Finally, soil organic carbon (SOC) was the primary driver varied with shifts in soil bacterial community composition. The encroachment was associated with elevated SOC, suggesting that shrub-mediated shifts in SOC might be responsible for changes in belowground bacterial community. Discussion This study demonstrated that shrub-encroached soils were associated with dramatic restructuring of bacterial communities, suggesting that belowground bacterial communities appear to be sensitive indicators of vegetation type. Our study indicates that the increased shrub-encroached intensity in Inner Mongolia will likely trigger large-scale disruptions in both aboveground plant and belowground bacterial communities across the region.

scholarly journals Pavement Overrides the Effects of Tree Species on Soil Bacterial Communities

2021 ◽  
Vol 18 (4) ◽  
pp. 2168
Author(s):  
Yinhong Hu ◽  
Weiwei Yu ◽  
Bowen Cui ◽  
Yuanyuan Chen ◽  
Hua Zheng ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Bacterial Diversity ◽  
Community Composition ◽  
Tree Species ◽  
Bacterial Communities ◽  
Bacterial Community Composition ◽  
Soil Bacterial Community ◽  
Soil Bacterial Communities ◽  
Pine Stands ◽  
Soil Bacterial

Human disturbance and vegetation are known to affect soil microorganisms. However, the interacting effects of pavement and plant species on soil bacterial communities have received far less attention. In this study, we collected soil samples from pine (Pinus tabuliformis Carr.), ash (Fraxinus chinensis), and maple (Acer truncatum Bunge) stands that grew in impervious, pervious, and no pavement blocks to investigate the way pavement, tree species, and their interaction influence soil bacterial communities by modifying soil physicochemical properties. Soil bacterial community composition and diversity were evaluated by bacterial 16S amplicon sequencing. The results demonstrated that soil bacterial community composition and diversity did differ significantly across pavements, but not with tree species. The difference in soil bacterial community composition across pavements was greater in pine stands than ash and maple stands. Soil bacterial diversity and richness indices decreased beneath impervious pavement in pine stands, and only bacterial richness indices decreased markedly in ash stands, but neither showed a significant difference across pavements in maple stands. In addition, bacterial diversity did not differ dramatically between pervious pavement and no pavement soil. Taken together, these results suggest that pavement overwhelmed the effects of tree species on soil bacterial communities, and had a greater effect on soil bacterial communities in pine stands, followed by ash and maple stands. This study highlights the importance of anthropogenic disturbance, such as pavement, which affects soil microbial communities.

scholarly journals Shrub encroachment is associated with changes in soil bacterial community composition in a temperate grassland ecosystem

2018 ◽  
Vol 425 (1-2) ◽  
pp. 539-551 ◽  
Author(s):  
Xingjia Xiang ◽  
Sean M. Gibbons ◽  
He Li ◽  
Haihua Shen ◽  
Jingyun Fang ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Bacterial Community Composition ◽  
Shrub Encroachment ◽  
Temperate Grassland ◽  
Soil Bacterial Community ◽  
Grassland Ecosystem ◽  
Soil Bacterial

scholarly journals Quality of Irrigation Water Affects Soil Functionality and Bacterial Community Stability in Response to Heat Disturbance

2017 ◽  
Vol 84 (4) ◽  
Author(s):  
Sammy Frenk ◽  
Yitzhak Hadar ◽  
Dror Minz
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Resource Availability ◽  
Bacterial Communities ◽  
Anthropogenic Activities ◽  
Bacterial Community Composition ◽  
Treated Wastewater ◽  
Soil Bacterial Communities ◽  
High Resource ◽  
Soil Bacterial

ABSTRACTAnthropogenic activities alter the structure and function of a bacterial community. Furthermore, bacterial communities structured by the conditions the anthropogenic activities present may consequently reduce their stability in response to an unpredicted acute disturbance. The present mesocosm-scale study exposed soil bacterial communities to different irrigation water types, including freshwater, fertilized freshwater, treated wastewater, and artificial wastewater, and evaluated their response to a disturbance caused by heat. These effectors may be considered deterministic and stochastic forces common in agricultural operations of arid and semiarid regions. Bacterial communities under conditions of high mineral and organic carbon availability (artificial wastewater) differed from the native bacterial community and showed a proteobacterial dominance. These bacterial communities had a lower resistance to the heat treatment disturbance than soils under conditions of low resource availability (high-quality treated wastewater or freshwater). The latter soil bacterial communities showed a higher abundance of operational taxonomic units (OTUs) classified asBacilli. These results were elucidated by soil under conditions of high resource availability, which lost higher degrees of functional potential and had a greater bacterial community composition change. However, the functional resilience, after the disturbance ended, was higher under a condition of high resource availability despite the bacterial community composition shift and the decrease in species richness. The functional resilience was directly connected to the high growth rates of certainBacteroidetesand proteobacterial groups. A high stability was found in samples that supported the coexistence of both resistant OTUs and fast-growing OTUs.IMPORTANCEThis report presents the results of a study employing a hypothesis-based experimental approach to reveal the forces involved in determining the stability of a soil bacterial community to disturbance. The resultant postdisturbance bacterial community composition dynamics and functionality were analyzed. The paper demonstrates the relatedness of community structure and stability under cultivation conditions prevalent in an arid area under irrigation with water of different qualities. The use of common agricultural practices to demonstrate these features has not been described before. The combination of a fundamental theoretical issue in ecology with common and concerning disturbances caused by agricultural practice makes this study unique. Furthermore, the results of the present study have applicable importance regarding soil conservation, as it enables a better characterization and monitoring of stressed soil bacterial communities and possible intervention to reduce the stress. It will also be of valued interest in coming years, as fresh water scarcity and the use of alternative water sources are expected to rise globally.

From pine to pasture: land use history has long-term impacts on soil bacterial community composition and functional potential

2020 ◽  
Vol 96 (4) ◽  
Author(s):  
Syrie M Hermans ◽  
Matthew Taylor ◽  
Gwen Grelet ◽  
Fiona Curran-Cournane ◽  
Hannah L Buckley ◽  
...  
Keyword(s):  
Land Use ◽  
Bacterial Community ◽  
Community Composition ◽  
Bacterial Communities ◽  
Bacterial Community Composition ◽  
Reference Sites ◽  
Functional Potential ◽  
Soil Bacterial Communities ◽  
Soil Bacterial

ABSTRACT Bacterial communities are crucial to soil ecosystems and are known to be sensitive to environmental changes. However, our understanding of how present-day soil bacterial communities remain impacted by historic land uses is limited; implications for their functional potential are especially understudied. Through 16S rRNA gene amplicon and shotgun metagenomic sequencing, we characterized the structure and functional potential of soil bacterial communities after land use conversion. Sites converted from pine plantations to dairy pasture were sampled five- and eight-years post conversion. The bacterial community composition and functional potential at these sites were compared to long-term dairy pastures and pine forest reference sites. Bacterial community composition and functional potential at the converted sites differed significantly from those at reference sites (P = 0.001). On average, they were more similar to those in the long-term dairy sites and showed gradual convergence (P = 0.001). Differences in composition and functional potential were most strongly related to nutrients such as nitrogen, Olsen P and the carbon to nitrogen ratio. Genes related to the cycling of nitrogen, especially denitrification, were underrepresented in converted sites compared to long-term pasture soils. Together, our study highlights the long-lasting impacts land use conversion can have on microbial communities, and the implications for future soil health and functioning.

scholarly journals Short-interval reburns in the boreal forest alter soil bacterial communities, reflecting increased pH and poor conifer seedling establishment

2021 ◽  
Author(s):  
Jamie Woolet ◽  
Ellen Whitman ◽  
Marc-Andre Parisien ◽  
Dan K. Thompson ◽  
Mike D. Flannigan ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Boreal Forest ◽  
Community Composition ◽  
Bacterial Communities ◽  
Bacterial Community Composition ◽  
Short Interval ◽  
Fire Frequency ◽  
Soil Bacterial Communities ◽  
Soil Bacterial ◽  
Conifer Seedling

Increasing burn rates (percentage area burned annually) in some biomes are leading to fires burning in close succession, triggering rapid vegetation change as well as altering soil properties. Despite the importance of soil microbes for nutrient cycling and as plant symbionts, the effects of increased fire frequency on belowground microbial communities remain largely unknown. We present a study of the effects of short interval reburns (defined here as <20 years between fires) on soil bacterial communities in the boreal forest of northwestern Canada, using a paired site design that spans wetlands and uplands, with 50 sites total. We asked whether short interval reburns significantly alter soil bacterial community composition and richness, and which bacterial taxa are associated with greater or lower fire frequency. We found that, while short interval reburns had no significant effect on bacterial richness, there were significant changes in overall community composition. We did not find correlations between understory vegetation community dissimilarities and bacterial community dissimilarities, suggesting the primary drivers of changes induced by short interval reburns may differ between plants and microbes. We identified an abundant Blastococcus sp. that was consistently enriched in short interval reburns, in both wetlands and uplands, indicating its role as a strongly "pyrophilous" bacterium. We also identified an abundant Callaberonia sordidicola taxon as being consistently depleted in short interval reburns. This endophytic diazotrophic organism is a robust colonizer of pine and spruce seedlings and has the ability to increase seedling growth, due in part to large contributions of fixed nitrogen. Its depletion in short-interval reburn sites raises questions about whether this is contributing to - or merely reflects - poor conifer seedling recolonization post-fire at short-interval reburns.

scholarly journals The Effects of Pavement Types on Soil Bacterial Communities across Different Depths

2019 ◽  
Vol 16 (10) ◽  
pp. 1805 ◽  
Author(s):  
Weiwei Yu ◽  
Yinhong Hu ◽  
Bowen Cui ◽  
Yuanyuan Chen ◽  
Xiaoke Wang
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Bacterial Communities ◽  
Bacterial Community Composition ◽  
Shannon Index ◽  
Soil Bacterial Community ◽  
Total Carbon ◽  
Bacterial Composition ◽  
Soil Bacterial ◽  
Micro Organisms

Pavements have remarkable effects on topsoil micro-organisms, but it remains unclear how subsoil microbial communities respond to pavements. In this study, ash trees (Fraxinus Chinensis) were planted on pervious pavement (PP), impervious pavement (IPP), and non-pavement (NP) plots. After five years, we determined the soil bacterial community composition and diversity by high-throughput sequencing of the bacterial 16S rRNA gene. The results of our field experiment reveal that the presence of pavement changed soil bacterial community composition and decreased the Shannon index, but had no impact on the Chao 1 at the 0–20 cm layer. However, we achieved the opposite result at a depth of 20–80 cm. Furthermore, there was a significant difference in bacterial community composition using the Shannon index and the Chao 1 at the 80–100 cm layer. Soil total carbon (TC), total nitrogen (TN), available phosphorus (AP), NO3−-N, and available potassium (AK) were the main factors that influenced soil bacterial composition and diversity across different pavements. Soil bacterial composition and diversity had no notable difference between PP and IPPs at different soil layers. Our results strongly indicate that pavements have a greater impact on topsoil bacterial communities than do subsoils, and PPs did not provide a better habitat for micro-organisms when compared to IPPs in the short term.

scholarly journals Pyrosequencing-Based Assessment of Soil pH as a Predictor of Soil Bacterial Community Structure at the Continental Scale

2009 ◽  
Vol 75 (15) ◽  
pp. 5111-5120 ◽  
Author(s):  
Christian L. Lauber ◽  
Micah Hamady ◽  
Rob Knight ◽  
Noah Fierer
Keyword(s):  
Bacterial Community ◽  
Soil Ph ◽  
Bacterial Communities ◽  
Bacterial Community Structure ◽  
Spatial Scales ◽  
Bacterial Community Composition ◽  
Phylogenetic Structure ◽  
Soil Bacterial Communities ◽  
Soil Bacterial Community Structure ◽  
Soil Bacterial

ABSTRACT Soils harbor enormously diverse bacterial populations, and soil bacterial communities can vary greatly in composition across space. However, our understanding of the specific changes in soil bacterial community structure that occur across larger spatial scales is limited because most previous work has focused on either surveying a relatively small number of soils in detail or analyzing a larger number of soils with techniques that provide little detail about the phylogenetic structure of the bacterial communities. Here we used a bar-coded pyrosequencing technique to characterize bacterial communities in 88 soils from across North and South America, obtaining an average of 1,501 sequences per soil. We found that overall bacterial community composition, as measured by pairwise UniFrac distances, was significantly correlated with differences in soil pH (r = 0.79), largely driven by changes in the relative abundances of Acidobacteria, Actinobacteria, and Bacteroidetes across the range of soil pHs. In addition, soil pH explains a significant portion of the variability associated with observed changes in the phylogenetic structure within each dominant lineage. The overall phylogenetic diversity of the bacterial communities was also correlated with soil pH (R2 = 0.50), with peak diversity in soils with near-neutral pHs. Together, these results suggest that the structure of soil bacterial communities is predictable, to some degree, across larger spatial scales, and the effect of soil pH on bacterial community composition is evident at even relatively coarse levels of taxonomic resolution.

Sign in / Sign up

Export Citation Format

Share Document