Diversity and community structure of moss- and lichen-dwelling tardigrades (Tardigrada) along an altitudinal gradient in Cuba

2021 ◽  
pp. 1-18
Author(s):  
Rogelio Roberto Muñoz-Li ◽  
Abdiel Jover Capote

Abstract Elevation and anthropopression are important factors affecting terrestrial water bear dynamics. In the present study, we characterize the taxonomic composition, diversity, and community structure of tardigrades along an elevational gradient with different anthropopression in Alturas de Boniato, Santiago de Cuba. Samples were collected in four sampling sites and all tardigrades were extracted. Alpha diversity indices were calculated. Hierarchical community organization was determined and variation among sampling sites was calculated using the Jaccard index for beta diversity. Some variables that influenced composition and taxon diversity were also evaluated. A total of 413 tardigrades belonging to seven taxa and five eggs were found. The most abundant taxa were Paramacrobiotus sp., Macrobiotus sp. and Milnesium sp. 1. Differences between sampling sites were largely due to turnover, especially at the higher-elevation sites. Nesting characterized the lower-elevation sites. The variables that had the greatest influence on species composition were anthropopression and a mixture of various macro- and microenvironmental variables.

2021 ◽  
Vol 9 (5) ◽  
pp. 1033
Author(s):  
Alen K. Eskov ◽  
Alexei O. Zverev ◽  
Evgeny V. Abakumov

Microbial biodiversity parameters for tropical rainforests remain poorly understood. Whilst the soil microbiome accounts up to 95% of the total diversity of microorganisms in terrestrial ecosystems, the microbiome of suspended soils formed by vascular epiphytes remains completely unexplored. Samples of ground and suspended soils were collected in Cat Tien National Park, southern Vietnam. DNA extraction and sequencing were performed, and libraries of 16s rDNA gene sequences were analyzed. Alpha diversity indices of the microorganisms were the highest in the forest ground soil. In general, the microbiological diversity of all the soil types was found to be similar at the phylum level. Taxonomic composition of the bacterial communities in the suspended soils of plants from the same species are not closer than the taxonomic compositions of the communities in the suspended soils of different plant species. However, the beta diversity analysis revealed significant differences in the movement of mineral elements in terrestrial versus suspended soils. Our data showed that the suspended soils associated with vascular epiphytes were a depository of unique microbiological biodiversity. A contributing factor was the presence of large amounts of organic matter in the suspended soils—deposits collected by the epiphytes—which would have been degraded by termites if it had reached the ground. Further, the nutrient content of the suspended soils was prime for soil respiration activity and taxonomic microbial community biodiversity.


2021 ◽  
Author(s):  
Wei Dai ◽  
Ning Wang ◽  
Wenhui Wang ◽  
Xianfeng Ye ◽  
Zhongli Cui ◽  
...  

Abstract Myxobacteria are unique predatory microorganisms with a distinct social lifestyle. The associated taxa play key roles in the microbial food webs in different ecosystems and regulate the community structures of soil microbial communities. Compared with conditions under conventional management, under organic conditions, myxobacteria abundance increases in the soil, which could be related to the presence of abundant myxobacteria in the applied compost manure. In the present study, high-throughput sequencing technologies were used to investigate the distribution patterns and drivers of predatory myxobacteria community distribution patterns in four common compost manures. According to the results, there was a significant difference in predatory myxobacteria community structure among different compost manure treatments (P < 0.05). The alpha-diversity indices of myxobacteria community under swine manure compost were the lowest (Observed OTU richness = 13.25, Chao1 = 14.83, Shannon = 0.61), and those under wormcast were the highest (Observed OTU richness = 30.25, Chao1 = 31.65, Shannon = 2.62). Bacterial community diversity and Mg2+ and Ca2+ concentrations were the major factors influencing myxobacteria distribution patterns under different compost manure treatments. In addition, pH, total nitrogen, and organic carbon influenced myxobacteria distribution in compost manure. The predator–prey relationship between prey bacteria and myxobacteria and the interaction between myxobacteria and specific bacterial taxa (Micrococcales) in compost manure could explain the influence of bacteria on myxobacteria community structure. Further investigations on the in-situ distribution patterns of predatory myxobacteria and the key bacteria influencing their distribution are would advance our understanding of the ecological distribution patterns and functions of predatory microorganisms in the microbial world.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11792
Author(s):  
Mei Yang ◽  
Zhaoyong Shi ◽  
Bede S. Mickan ◽  
Mengge Zhang ◽  
Libing Cao

Background Global warming can alter plant productivity, and community composition which has consequences for soil-plant associated microorganisms. Arbuscular mycorrhizal fungi (AMF) are distributed widely and form symbiotic relationships with more than 80% of vascular plants and play a key role in nutrient cycling processes at the ecosystem scale. Methods A simulated warming experiment at multiple elevations (3,000, 3,500, 3,800, and 4,170 m) was conducted utilizing an in-situ open-top chamber (OTC) for exploring the effect of global warming on AMF community structure in the Qinghai-Tibet Plateau (QTP). This region has been identified as one of the most sensitive areas to climatic changes. Soil DNA was extracted and sequenced using next the Mi-Seq platform for diversity profiling. Results AMF richness was higher under the simulated warming chamber, however this only occurred in the elevation of 3,500 m. Warming did not alter other AMF alpha diversity indices (e.g. Shannon, Ace, and Simpson evenness index). Glomus and Acaulospora were the dominate AMF genera as assessed through their relative abundance and occurrence in control and warming treatments at the different elevations. Conclusion Warming changed significantly AMF community. The effects of warming on AMF community structure varied depend on elevations. Moreover, the occurrences of AMF in different genera were also presented the different responses to warming in four elevations.


2021 ◽  
Author(s):  
Marlène Chiarello ◽  
Mark McCauley ◽  
Sébastien Villéger ◽  
Colin R Jackson

Abstract BackgroundAdvances in the analysis of amplicon sequence datasets have introduced a methodological shift in how research teams investigate microbial biodiversity, away from the classification and downstream analyses of traditional operational taxonomic units (OTUs), and towards the usage of amplicon sequence variants (ASVs). While ASVs have several inherent properties that make them desirable compared to OTUs, questions remain as to the influence that these pipelines have on the ecological patterns being assessed, especially when compared to other methodological choices made when processing data (e.g. rarefaction) and computing diversity indices. ResultsWe compared the respective influences of using ASVs vs. OTU-based pipelines, rarefaction of the community table, and OTU similarity threshold (97% vs. 99%) on the ecological signals detected in freshwater invertebrate and environmental (sediment, seston) 16S rRNA data sets, determining the effects on alpha diversity, beta diversity and taxonomic composition. While the choice of OTU vs. ASV pipeline significantly influenced unweighted alpha and beta diversities and changed the ecological signal detected, weighted indices such as the Shannon index, Bray-Curtis dissimilarity, and weighted Unifrac scores were not impacted by the pipeline followed. By comparison, OTU threshold and rarefaction had a minimal impact effect on all measurements, although rarefaction improved overall signals, especially in OTU-based datasets. The identification of major classes and genera identified revealed significant discrepancies across methodologies. ConclusionWe provide a list of recommendations for the analysis of 16S rRNA amplicon data. We notably recommend the use of ASVs when analyzing alpha-diversity patterns, especially in species-rich or environmental samples. Abundance weighted alpha- and beta-diversity indices should also be preferred compared to ones based on the presence-absence of biological units.


Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1938
Author(s):  
Han Aricha ◽  
Huasai Simujide ◽  
Chunjie Wang ◽  
Jian Zhang ◽  
Wenting Lv ◽  
...  

Mongolian cattle from China have strong adaptability and disease resistance. We aimed to compare the gut microbiota community structure and diversity in grazing Mongolian cattle from different regions in Inner Mongolia and to elucidate the influence of geographical factors on the intestinal microbial community structure. We used high throughput 16S rRNA sequencing to analyze the fecal microbial community and diversity in samples from 60 grazing Mongolian cattle from Hulunbuir Grassland, Xilingol Grassland, and Alxa Desert. A total of 2,720,545 high-quality reads and sequences that were 1,117,505,301 bp long were obtained. Alpha diversity among the three groups showed that the gut microbial diversity in Mongolian cattle in the grasslands was significantly higher than that in the desert. The dominant phyla were Firmicutes and Bacteroidetes, whereas Verrucomicrobia presented the highest abundance in the gut of cattle in the Alxa Desert. The gut bacterial communities in cattle from the grasslands versus the Alxa Desert were distinctive, and those from the grasslands were closely clustered. Community composition analysis revealed significant differences in species diversity and richness. Overall, the composition of the gut microbiota in Mongolian cattle is affected by geographical factors. Gut microbiota may play important roles in the geographical adaptations of Mongolian cattle.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hua Zha ◽  
Fengping Liu ◽  
Zongxin Ling ◽  
Kevin Chang ◽  
Jiezuan Yang ◽  
...  

AbstractType 2 diabetes mellitus (T2DM) influences the human health and can cause significant illnesses. The genitourinary microbiome profiles in the T2DM patients remain poorly understood. In the current study, a series of bioinformatic and statistical analyses were carried out to determine the multiple bacteria associated with the more dysbiotic genitourinary microbiomes (i.e., those with lower dysbiosis ratio) in T2DM patients, which were sequenced by Illumina-based 16S rRNA gene amplicon sequencing. All the genitourinary microbiomes from 70 patients with T2DM were clustered into three clusters of microbiome profiles, i.e., Cluster_1_T2DM, Cluster_2_T2DM and Cluster_3_T2DM, with Cluster_3_T2DM at the most dysbiotic genitourinary microbial status. The three clustered T2DM microbiomes were determined with different levels of alpha diversity indices, and driven by distinct urinalysis variables. OTU12_Clostridiales and OTU28_Oscillospira were likely to drive the T2DM microbiomes to more dysbiotic status, while OTU34_Finegoldia could play a vital role in maintaining the least dysbiotic T2DM microbiome (i.e., Cluster_1_T2DM). The functional metabolites K08300_ribonuclease E, K01223_6-phospho-beta-glucosidase and K00029_malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+) were most associated with Cluster_1_T2DM, Cluster_2_T2DM and Cluster_3_T2DM, respectively. The characteristics and multiple bacteria associated with the more dysbiotic genitourinary microbiomes in T2DM patients may help with the better diagnosis and management of genitourinary dysbiosis in T2DM patients.


2005 ◽  
Vol 51 (6) ◽  
pp. 433-439 ◽  
Author(s):  
J A Humphries ◽  
A M.H Ashe ◽  
J A Smiley ◽  
C G Johnston

Trichloroethylene (TCE) is a prevalent contaminant of groundwater that can be cometabolically degraded by indigenous microbes. Groundwater contaminated with TCE from a US Department of Energy site in Ohio was used to characterize the site-specific impact of phenol on the indigenous bacterial community for use as a possible remedial strategy. Incubations of14C-TCE-spiked groundwater amended with phenol showed increased TCE mineralization compared with unamended groundwater. Community structure was determined using DNA directly extracted from groundwater samples. This DNA was then analyzed by amplified ribosomal DNA restriction analysis. Unique restriction fragment length polymorphisms defined operational taxonomic units that were sequenced to determine phylogeny. DNA sequence data indicated that known TCE-degrading bacteria including relatives of Variovorax and Burkholderia were present in site water. Diversity of the amplified microbial rDNA clone library was lower in phenol-amended communities than in unamended groundwater (i.e., having Shannon–Weaver diversity indices of 2.0 and 2.2, respectively). Microbial activity was higher in phenol-amended ground water as determined by measuring the reduction of 2-(p-iodophenyl)-3(p-nitrophenyl)-5-phenyl tetrazolium chloride. Thus phenol amendments to groundwater correlated with increased TCE mineralization, a decrease in diversity of the amplified microbial rDNA clone library, and increased microbial activity.Key words: community structure, trichloroethylene, degradation, groundwater.


2021 ◽  
Vol 11 (1) ◽  
pp. 35
Author(s):  
Zahra A. Barandouzi ◽  
Joochul Lee ◽  
Kendra Maas ◽  
Angela R. Starkweather ◽  
Xiaomei S. Cong

The interplay between diet and gut microbiota has gained interest as a potential contributor in pathophysiology of irritable bowel syndrome (IBS). The purpose of this study was to compare food components and gut microbiota patterns between IBS patients and healthy controls (HC) as well as to explore the associations of food components and microbiota profiles. A cross-sectional study was conducted with 80 young adults with IBS and 21 HC recruited. The food frequency questionnaire was used to measure food components. Fecal samples were collected and profiled by 16S rRNA Illumina sequencing. Food components were similar in both IBS and HC groups, except in caffeine consumption. Higher alpha diversity indices and altered gut microbiota were observed in IBS compared to the HC. A negative correlation existed between total observed species and caffeine intake in the HC, and a positive correlation between alpha diversity indices and dietary fiber in the IBS group. Higher alpha diversity and gut microbiota alteration were found in IBS people who consumed caffeine more than 400 mg/d. Moreover, high microbial diversity and alteration of gut microbiota composition in IBS people with high caffeine consumption may be a clue toward the effects of caffeine on the gut microbiome pattern, which warrants further study.


2021 ◽  
Vol 22 (4) ◽  
pp. 2131
Author(s):  
Stefania Pane ◽  
Anna Sacco ◽  
Andrea Iorio ◽  
Lorenza Romani ◽  
Lorenza Putignani

Background: Strongyloidiasis is a neglected tropical disease caused by the intestinal nematode Strongyloides stercoralis and characterized by gastrointestinal and pulmonary involvement. We report a pediatric case of strongyloidiasis to underline the response of the host microbiota to the perturbation induced by the nematode. Methods: We performed a 16S rRNA-metagenomic analysis of the gut microbiota of a 7-year-old female during and after S. stercolaris infection, investigating three time-point of stool samples’ ecology: T0- during parasite infection, T1- a month after parasite infection, and T2- two months after parasite infection. Targeted-metagenomics were used to investigate ecology and to predict the functional pathways of the gut microbiota. Results: an increase in the alpha-diversity indices in T0-T1 samples was observed compared to T2 and healthy controls (CTRLs). Beta-diversity analysis showed a shift in the relative abundance of specific gut bacterial species from T0 to T2 samples. Moreover, the functional prediction of the targeted-metagenomics profiles suggested an enrichment of microbial glycan and carbohydrate metabolisms in the T0 sample compared with CTRLs. Conclusions: The herein report reinforces the literature suggestion of a putative direct or immune-mediated ability of S. stercolaris to promote the increase in bacterial diversity.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shinya Hosokawa ◽  
Kyosuke Momota ◽  
Anthony A. Chariton ◽  
Ryoji Naito ◽  
Yoshiyuki Nakamura

AbstractDiversity indices are commonly used to measure changes in marine benthic communities. However, the reliability (and therefore suitability) of these indices for detecting environmental change is often unclear because of small sample size and the inappropriate choice of communities for analysis. This study explored uncertainties in taxonomic density and two indices of community structure in our target region, Japan, and in two local areas within this region, and explored potential solutions. Our analysis of the Japanese regional dataset showed a decrease in family density and a dominance of a few species as sediment conditions become degraded. Local case studies showed that species density is affected by sediment degradation at sites where multiple communities coexist. However, two indices of community structure could become insensitive because of masking by community variability, and small sample size sometimes caused misleading or inaccurate estimates of these indices. We conclude that species density is a sensitive indicator of change in marine benthic communities, and emphasise that indices of community structure should only be used when the community structure of the target community is distinguishable from other coexisting communities and there is sufficient sample size.


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