BACTERIAL COMMUNITY SUCCESSION AND INFLUENCING FACTORS OF IMPERATA CYLINDRICA LITTER DECOMPOSITION IN A DEGRADED COPPER TAILINGS DAM OF CHINA

Litter decomposition is a critical component of the ecological nutritional transformation process. It is particularly important to investigate characteristics and interactions of bacterial communities in litter decomposition in heavy metal polluted degrade areas, which will help clarify driving mechanisms of organic matter and nutrient cycling in mining areas that harbor contaminated soil. Imperata cylindrical was the dominant plant species in the degrade area investigated; thus, we selected this species as research object. Here we explore bacterial community characteristics and key microbial groups as well as driving factors of litter decomposition using in-situ litter decomposition experiments. The nutrient content of I. cylindrica decreased, while the litter pH status increased as decomposition progressed in one of the three sub-dams investigated (i.e., S516). Proteobacteria and Actinobacteriota were the dominant bacterial phyla during the different litter decomposition stages. Moreover, the role of Friedmanniella was critical in sustaining both structure and function of the bacterial community during the early decomposition stage. Quadrisphaera became the dominant species as litter decomposition progressed. Litter properties and enzyme activities both had significant effects on litter bacterial community characteristics, whose driving factors varied during different restoration stages. The bacterial community dynamics of litter were affected primarily by litter properties during the decomposition process. Furthermore, the most crucial factors that impacted bacterial litter structure were pH and copper content. Findings will help to deepen our understanding of litter decomposition mechanisms in degraded ecosystems, while also providing a scientific basis for improving effectiveness of material circulation and nutrient transformation in degrade ecosystems.

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Bacterial Community Characteristics and Enzyme Activities in Bothriochloa ischaemum Litter Over Progressive Phytoremediation Years in a Copper Tailings Dam

Frontiers in Microbiology ◽

10.3389/fmicb.2020.565806 ◽

2020 ◽

Vol 11 ◽

Author(s):

Tong Jia ◽

Yuwen Wang ◽

Baofeng Chai

Keyword(s):

Bacterial Community ◽

Litter Decomposition ◽

Enzyme Activities ◽

Nutrient Content ◽

Scientific Basis ◽

Positive Interactions ◽

Community Characteristics ◽

Bothriochloa Ischaemum ◽

Copper Tailings ◽

Structural Framework

Litter decomposition is the key link between material circulation and energy flow in ecosystems, resulting from the activity of resident microbes and various enzymes. This study investigated enzyme activity in litter and associated microbial community characteristics to help clarify the internal mechanisms associated with litter decomposition, while also providing researchers a scientific basis for soil remediation in mining areas. Results confirmed that the nutrient content of Bothriochloa ischaemum litter significantly increased as phytoremediation years progressed, while enzyme activities in litter varied over different phytoremediation years. During the litter decomposition process, cellulase predominated in the early phytoremediation stage and catalase predominated in the intermediate phytoremediation stage. Obvious differences were found in bacterial community structure and diversity over progressive phytoremediation years. Predominant bacterial genera mainly included Massilia, Sphingomonas, Curtobacterium, Amnibacterium, and Methylobacterium. Moreover, Methylorosula and Jatrophihabitans had relatively higher betweenness centrality, and played important roles in bacterial community positive interactions. Additionally, total nitrogen (TN) and total zinc in soil, sucrase and catalase activity in litter were the main environmental factors that affected the structural framework of bacteria in B. ischaemum litter. However, TN had the greatest overall effect on the structural framework of bacteria in litter. Results from this study can help our understanding of the role that litter plays in degraded ecosystems. Our results also provide a scientific basis for improving poor quality soil in areas affected by copper tailings while also amending ecological restoration efficiency.

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Bacterial community dynamics during embryonic development of the little skate (Leucoraja erinacea)

Animal Microbiome ◽

10.1186/s42523-021-00136-x ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Katelyn Mika ◽

Alexander S. Okamoto ◽

Neil H. Shubin ◽

David B. Mark Welch

Keyword(s):

Bacterial Community ◽

Embryonic Development ◽

Community Dynamics ◽

Internal Surface ◽

Amplicon Sequencing ◽

Phylogenetic Position ◽

Published Data ◽

Bacterial Phyla ◽

Bacterial Community Dynamics ◽

Egg Capsule

Abstract Background Microbial transmission from parent to offspring is hypothesized to be widespread in vertebrates. However, evidence for this is limited as many evolutionarily important clades remain unexamined. There is currently no data on the microbiota associated with any Chondrichthyan species during embryonic development, despite the global distribution, ecological importance, and phylogenetic position of this clade. In this study, we take the first steps towards filling this gap by investigating the microbiota associated with embryonic development in the little skate, Leucoraja erinacea, a common North Atlantic species and popular system for chondrichthyan biology. Methods To assess the potential for bacterial transmission in an oviparous chondrichthyan, we used 16S rRNA amplicon sequencing to characterize the microbial communities associated with the skin, gill, and egg capsule of the little skate, at six points during ontogeny. Community composition was analyzed using the QIIME2 pipeline and microbial continuity between stages was tracked using FEAST. Results We identify site-specific and stage-specific microbiota dominated by the bacterial phyla Proteobacteria and Bacteroidetes. This composition is similar to, but distinct from, that of previously published data on the adult microbiota of other chondrichthyan species. Our data reveal that the skate egg capsule harbors a highly diverse bacterial community–particularly on the internal surface of the capsule–and facilitates intergenerational microbial transfer to the offspring. Embryonic skin and external gill tissues host similar bacterial communities; the skin and gill communities later diverge as the internal gills and skin denticles develop. Conclusions Our study is the first exploration of the chondrichthyan microbiota throughout ontogeny and provides the first evidence of vertical transmission in this group.

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Dynamic succession of substrate-associated bacterial composition and function duringGanoderma lucidumgrowth

PeerJ ◽

10.7717/peerj.4975 ◽

2018 ◽

Vol 6 ◽

pp. e4975 ◽

Cited By ~ 7

Author(s):

Bo Zhang ◽

Lijuan Yan ◽

Qiang Li ◽

Jie Zou ◽

Hao Tan ◽

...

Keyword(s):

Bacterial Community ◽

Community Composition ◽

Community Dynamics ◽

Bacterial Community Composition ◽

Growth Stages ◽

Bacterial Phyla ◽

Medicinal Fungus ◽

Bacterial Community Dynamics ◽

Functional Pathway ◽

And Function

BackgroundGanoderma lucidum, a valuable medicinal fungus, is widely distributed in China. It grows alongside with a complex microbial ecosystem in the substrate. As sequencing technology advances, it is possible to reveal the composition and functions of substrate-associated bacterial communities.MethodsWe analyzed the bacterial community dynamics in the substrate during the four typical growth stages ofG. lucidumusing next-generation sequencing.ResultsThe physicochemical properties of the substrate (e.g. acidity, moisture, total nitrogen, total phosphorus and total potassium) changed between different growth stages. A total of 598,771 sequences from 12 samples were obtained and assigned to 22 bacterial phyla.ProteobacteriaandFirmicuteswere the dominant phyla. Bacterial community composition and diversity significantly differed between the elongation stage and the other three growth stages. LEfSe analysis revealed a large number of bacterial taxa (e.g.Bacteroidetes,AcidobacteriaandNitrospirae) with significantly higher abundance at the elongation stage. Functional pathway prediction uncovered significant abundance changes of a number of bacterial functional pathways between the elongation stage and other growth stages. At the elongation stage, the abundance of the environmental information processing pathway (mainly membrane transport) decreased, whereas that of the metabolism-related pathways increased.DiscussionThe changes in bacterial community composition, diversity and predicted functions were most likely related to the changes in the moisture and nutrient conditions in the substrate with the growth ofG. lucidum, particularly at the elongation stage. Our findings shed light on theG. lucidum-bacteria-substrate relationships, which should facilitate the industrial cultivation ofG. lucidum.

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Litter Decomposition of Imperata cylindrica in a Copper Tailing Areas With Different Restoration History: Fungal Community Dynamics and Driving Factors

Frontiers in Microbiology ◽

10.3389/fmicb.2021.780015 ◽

2021 ◽

Vol 12 ◽

Author(s):

Tong Jia ◽

Xuerong Wang ◽

Tingyan Guo ◽

Baofeng Chai

Keyword(s):

Heavy Metals ◽

Community Structure ◽

Litter Decomposition ◽

Fungal Community ◽

Enzyme Activities ◽

Community Dynamics ◽

Driving Factors ◽

Imperata Cylindrica ◽

Fungal Communities ◽

Fungal Community Structure

Microorganisms drive litter decomposition while maintaining the chemical cycle of ecosystems. We used the dominant vegetation (Imperata cylindrica) in the mining area selected for this study for this experiment to explore fungal community characteristics, key fungal groups, and their associative driving factors during I. cylindrica litter decomposition. Maximum litter C/N values occurred 100days after the commencement of the decomposition experiment during all different recovery years in this copper tailings area. Heavy metals in litter [copper (Cu), zinc (Zn), plumbum (Pb), and cadmium (Cd)] accumulated gradually with decomposition. The dominant fungal phyla observed in the community were Ascomycota and Basidiomycota, while the classes Sordariomycetes and Eurotiomycetes significantly increased as litter decomposition progressed. Degrees of connectivity and interaction between fungal communities were highest during the early litter decomposition stage. Sordariomycetes, Dothideomycetes, and Leotiomycetes all played critical roles in maintaining fungal community relationships. The effect of physicochemical properties and enzyme activities in I. cylindrica litter was significant on the dominant fungi, while driving factors that affected fungal communities differed over different recovery stages. Total nitrogen (TN), heavy metals, pH, and enzyme activities in the little were significantly correlated with fungal community composition. Litter properties throughout the litter decomposition process mainly affected the dynamics of the fungal community structure. The main environmental factors that affected fungal community structure were copper content and pH. Dichotomopilus, Trichoderma, Knufia, Phialophora, Oxyporus, and Monocillium, which all played important roles in litter decomposition, positively correlated with heavy metals, sucrase, and catalase. Finally, results from this study will help us better clarify litter decomposition mechanisms in degraded ecosystems as well as provide a scientific basis for improving species cycling and nutrient transformation efficiency in mining ecosystems.

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