Additions of Pyrite or Chalcopyrite Alters the Microbial Community Diversity, Composition and Function in Sphalerite Bioleaching Systems

2015 ◽  
Vol 1130 ◽  
pp. 454-458 ◽  
Author(s):  
Yun Hua Xiao ◽  
Xue Duan Liu ◽  
Hua Qun Yin ◽  
Wei Ling Dong ◽  
Yi Li Liang ◽  
...  

Extraction of zinc from sphalerite using bio-hydrometallurgical technologies has become more and more popular. This study used an artificial microbial community with five known microorganisms to examine the relationship among microbial diversity, composition, and function (e.g., zinc extraction rates) in sphalerite bioleaching systems with additional pyrite (SP), chalcopyrite (SC), or both (SPC). Real-time quantitative PCR (qPCR) analysis showed that additional pyrite or chalcopyrite changed the microbial community composition dramatically during the sphalerite bioleaching process. Shannon diversity index, compared with Sphalerite (0.109), showed an increase in SP (0.508), SC (0.536) and SPC (0.289) on day 30, and zinc extraction rates were enhanced by about 12.1%, 4.3% and 9.47%, respectively. Also, additional pyrite or chalcopyrite made ORP and the concentrations of Fe3+, Zn2+ and H+ increased, which were the main factors on shaping the microbial community composition by Mantel test analysis. We developed a unitary model, showing that additional pyrite or chalcopyrite increased the microbial community diversity.

2017 ◽  
Vol 75 (1) ◽  
pp. 193-203 ◽  
Author(s):  
Vincent Scola ◽  
Jean-Baptiste Ramond ◽  
Aline Frossard ◽  
Olivier Zablocki ◽  
Evelien M. Adriaenssens ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Lucas Fillinger ◽  
Kerstin Hürkamp ◽  
Christine Stumpp ◽  
Nina Weber ◽  
Dominik Forster ◽  
...  

Understanding microbial community dynamics in the alpine cryosphere is an important step toward assessing climate change impacts on these fragile ecosystems and meltwater-fed environments downstream. In this study, we analyzed microbial community composition, variation in community alpha and beta diversity, and the number of prokaryotic cells and virus-like particles (VLP) in seasonal snowpack from two consecutive years at three high altitude mountain summits along a longitudinal transect across the European Alps. Numbers of prokaryotic cells and VLP both ranged around 104 and 105 per mL of snow meltwater on average, with variation generally within one order of magnitude between sites and years. VLP-to-prokaryotic cell ratios spanned two orders of magnitude, with median values close to 1, and little variation between sites and years in the majority of cases. Estimates of microbial community alpha diversity inferred from Hill numbers revealed low contributions of common and abundant microbial taxa to the total taxon richness, and thus low community evenness. Similar to prokaryotic cell and VLP numbers, differences in alpha diversity between years and sites were generally relatively modest. In contrast, community composition displayed strong variation between sites and especially between years. Analyses of taxonomic and phylogenetic community composition showed that differences between sites within years were mainly characterized by changes in abundances of microbial taxa from similar phylogenetic clades, whereas shifts between years were due to significant phylogenetic turnover. Our findings on the spatiotemporal dynamics and magnitude of variation of microbial abundances, community diversity, and composition in surface snow may help define baseline levels to assess future impacts of climate change on the alpine cryosphere.


2008 ◽  
Vol 74 (24) ◽  
pp. 7585-7595 ◽  
Author(s):  
Yiping Cao ◽  
Peter G. Green ◽  
Patricia A. Holden

ABSTRACT Denitrifying microbial communities and denitrification in salt marsh sediments may be affected by many factors, including environmental conditions, nutrient availability, and levels of pollutants. The objective of this study was to examine how microbial community composition and denitrification enzyme activities (DEA) at a California salt marsh with high nutrient loading vary with such factors. Sediments were sampled from three elevations, each with different inundation and vegetation patterns, across 12 stations representing various salinity and nutrient conditions. Analyses included determination of cell abundance, total and denitrifier community compositions (by terminal restriction fragment length polymorphism), DEA, nutrients, and eluted metals. Total bacterial (16S rRNA) and denitrifier (nirS) community compositions and DEA were analyzed for their relationships to environmental variables and metal concentrations via multivariate direct gradient and regression analyses, respectively. Community composition and DEA were highly variable within the dynamic salt marsh system, but each was strongly affected by elevation (i.e., degree of inundation) and carbon content as well as by selected metals. Carbon content was highly related to elevation, and the relationships between DEA and carbon content were found to be elevation specific when evaluated across the entire marsh. There were also lateral gradients in the marsh, as evidenced by an even stronger association between community composition and elevation for a marsh subsystem. Lastly, though correlated with similar environmental factors and selected metals, denitrifier community composition and function appeared uncoupled in the marsh.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jing Zhu ◽  
Xiang Sun ◽  
Qi-Yong Tang ◽  
Zhi-Dong Zhang

Endophytes are essential components of plant microbiota. Studies have shown that environmental factors and seasonal alternation can change the microbial community composition of plants. However, most studies have mainly emphasized the transitive endophyte communities and seasonal alternation but paid less attention to their persistence through multiple seasons. Kalidium schrenkianum is a perennial halophyte growing in an arid habitat with radiation stress (137Cs) in northwest China. In this study, K. schrenkianum growing under different environmental stresses were selected to investigate the dynamics and persistency of endophytic microbial communities amid seasons in a year. The results showed that Gammaproteobacteria and unassigned Actinobacteria were the most dominant bacterial communities, while the most dominant fungal communities were Dothideomycetes, unassigned Fungi, and Sodariomycetes. The bacterial community diversity in roots was higher than that in aerial tissues, and root communities had higher diversity in summer and autumn. In contrast, the fungal community diversity was higher in aerial tissues comparing to roots, and the highest diversity was in spring. Season was a determinant factor in the microbial community composition in the roots but not in the aerial tissues. RaupCrick index suggested that the bacterial communities were mainly shaped by stochastic processes. Our research investigated the community traits and members with temporal persistency. For example, bacterial taxa Afipia, Delftia, Stenotrophomonas, Xanthomonadaceae_B_OTU_211, and fungal taxa Neocamarosporium F_OTU_388, F_OTU_404, F_OTU_445, and unassigned Fungi F_OTU_704, F_OTU_767 showed higher frequencies than predicted in all the four seasons tested with neutral community model. The networks of co-occurrence associations presented in two or more seasons were visualized which suggested potential time-continuous core modules in most communities. In addition, the community dynamics and persistency also showed different patterns by radiation levels. Our findings would enhance our understanding of the microbial community assembly under environmental stress, and be promising to improve the development of integrated concept of core microbiome in future.


2019 ◽  
Vol 78 (4) ◽  
pp. 1035-1039 ◽  
Author(s):  
Renee Johansen ◽  
Michaeline Albright ◽  
La Verne Gallegos-Graves ◽  
Deanna Lopez ◽  
Andreas Runde ◽  
...  

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