scholarly journals Effects of ultraviolet radiation on the community structure and metabolic pathways of A2O process at Plateau environment

Author(s):  
Zong Yongchen ◽  
He Qiang ◽  
Guo Mingzhe ◽  
You Junhao ◽  
Zhang Dongyan

Abstract Water treatment ecosystem provides important habitats for various bacterial communities. However, the response mechanism of this ecosystem under ultraviolet rays is not yet clear. In the study, 16S rRNA gene sequencing is used to study the bacterial community structure and metabolic pathways under 5 samples of ultraviolet irradiation times. In general, the bacterial communities of the five samples are different, which indicates that the ultraviolet radiation time has an impact on the bacterial community structure. Analysis of driving factors shows that UV, COD, pH, TN and NH3-N have an impact on the relative abundance of key species. Key species under ultraviolet irradiation are Bacteroidetes, Proteobacteria, Actinobacteria, Firmicutes, Chloroflexi, and Chlamydiae, accounting for 96.69%ཞ98.30%, and ultraviolet irradiation has a significant inhibitory effect on the relative abundance. As the dominant bacterial phyla in Plateau environment, Chlamydiae is discovered for the first time. The network co-occurrence diagrams constructed under different ultraviolet radiation show that each sample is composed of three independent network diagrams. There are 6 common dominant phyla and 33 common dominant bacterial genera in each sample, which reveals that the structure of the ecosystem is composed of more similar microorganisms, rather than random phenomena. It also reflects the competitive relationship between species and the adaptability of bacteria to the environment. Through the analysis of metabolic pathways, it is found that the dominant metabolic pathways in high altitude habitats have certain changes under ultraviolet radiation. Further analysis of carbon, nitrogen and phosphorus metabolic pathways shows that the relative abundance of related metabolic pathways has a certain change, but the difference in metabolic maps is small, that is, the effect of ultraviolet radiation is mainly reflected in the relative abundance of metabolic pathways. These findings indicate that ultraviolet radiation in Plateau environment as an important influencing factor has an impact on microbial structure and metabolic pathways. This research provides an important theoretical basis for further understanding of water treatment ecosystem in Plateau environment, and also provides a new perspective for the development of water treatment ecosystem.

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xu Jiang ◽  
Hui Ma ◽  
Qing-lei Zhao ◽  
Jun Yang ◽  
Cai-yun Xin ◽  
...  

AbstractAs an important form of sustainable agriculture, rice-crab (Eriocheir sinensis) co-culture is rapid developing worldwide. However, the knowledge on the bacterial communities of the different components of the system is limited. In this study, we investigated the bacterial community structure in paddy soil and ditch sediment by using high-throughput sequencing technology. The results showed that compared with the ditch sediment, the content of NH4+-N in paddy soil decreased by 62.31%, and the content of AP (available phosphorus) increased by 172.02% (P < 0.05). The most abundant phyla in paddy soil and ditch sediment were Proteobacteria, Bacteroidetes and Chloroflexi, whose relative abundance was above 65%. Among the dominant genera, the relative abundance of an uncultured bacterium genus of Saprospiraceae and an uncultured bacterium genus of Lentimicrobiaceae in paddy soil was significantly lower than ditch sediment (P < 0.05). Alpha diversity indicated that the bacterial diversity of paddy soil and ditch sediment was similar. The bacterial community structure was affected by the relative abundance of bacteria, not the species of bacteria. Redundancy analysis (RDA) showed that the bacterial communities in paddy soil and ditch sediment were correlated with physicochemical properties. Our findings showed that the bacterial community structure was distinct in paddy soil and ditch sediment under rice-crab co-culture probably due to their different management patterns. These results can provide theoretical support for improving rice-crab co-culture technology.


2020 ◽  
Vol 15 (No. 2) ◽  
pp. 85-92
Author(s):  
Chengsen Zhao ◽  
Qingqing Xu ◽  
Lin Chen ◽  
Xiaoqing Li ◽  
Yutian Meng ◽  
...  

In this four-year study, we focused on the impacts of a biochar application on physicochemical soil properties (soil total carbon, total nitrogen, total potassium, total phosphorus, available nitrogen, available potassium, available phosphorus, pH, bulk density and moisture) and bacterial communities in an Albic Clayic Luvisol. The biochar was applied to plots only once with rates of 0, 10, 20 and 30 t/ha at the beginning of the experiment. The soil samples were collected from the surface (0–10 cm) and second depth (10–20 cm) soil layers after four years. The results showed that that the soil total carbon (TC) and pH increased, but the soil bulk density (BD) decreased with the biochar application. The soil bacterial sequences determined by the Illumina MiSeq method resulted in a decrease in the relative abundance of Acidobacteria, but an increase in the Actinobacteria with the biochar application. The bacterial diversity was significantly influenced by the biochar application. The nonmetric multidimensional scaling (NMDS) and canonical correspondence analysis (CCA) indicated that the soil bacterial community structure was affected by both the biochar addition and the soil depth. The Mantel test analysis indicated that the bacterial community structure significantly correlated to a soil with a pH (r = 0.525, P = 0.001), bulk density (r = 0.539, P = 0.001) and TC (r = 0.519, P = 0.002) only. In addition, most of the differences in the soil properties, bacterial relative abundance and community composition in the second depth soil layer were greater than those in the surface soil layer.


Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1465
Author(s):  
Chao Shen ◽  
Liuyan Huang ◽  
Guangwu Xie ◽  
Yulai Wang ◽  
Zongkai Ma ◽  
...  

Increasing discharge of plastic debris into aquatic ecosystems and the worsening ecological risks have received growing attention. Once released, plastic debris could serve as a new substrate for microbes in waters. The complex relationship between plastics and biofilms has aroused great interest. To confirm the hypothesis that the presence of plastic in water affects the composition of biofilm in natural state, in situ biofilm culture experiments were conducted in a lake for 40 days. The diversity of biofilm attached on natural (cobble stones (CS) and wood) and plastic substrates (Polyethylene terephthalate (PET) and Polymethyl methacrylate (PMMA)) were compared, and the community structure and composition were also analyzed. Results from high-throughput sequencing of 16S rRNA showed that the diversity and species richness of biofilm bacterial communities on natural substrate (observed species of 1353~1945, Simpson index of 0.977~0.989 and Shannon–Wiener diversity index of 7.42~8.60) were much higher than those on plastic substrates (observed species of 900~1146, Simpson index of 0.914~0.975 and Shannon–Wiener diversity index of 5.47~6.99). The NMDS analyses were used to confirm the taxonomic significance between different samples, and Anosim (p = 0.001, R = 0.892) and Adonis (p = 0.001, R = 808, F = 11.19) demonstrated that this classification was statistically rigorous. Different dominant bacterial communities were found on plastic and natural substrates. Alphaproteobacterial, Betaproteobacteria and Synechococcophycideae dominated on the plastic substrate, while Gammaproteobacteria, Phycisphaerae and Planctomycetia played the main role on the natural substrates. The bacterial community structure of the two substrates also showed significant difference which is consistent with previous studies using other polymer types. Our results shed light on the fact that plastic debris can serve as a new habitat for biofilm colonization, unlike natural substrates, pathogens and plastic-degrading microorganisms selectively attached to plastic substrates, which affected the bacterial community structure and composition in aquatic environment. This study provided a new insight into understanding the potential impacts of plastics serving as a new habitat for microbial communities in freshwater environments. Future research should focus on the potential impacts of plastic-attached biofilms in various aquatic environments and the whole life cycle of plastics (i.e., from plastic fragments to microplastics) and also microbial flock characteristics using microbial plastics in the natural environment should also be addressed.


Animals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 701 ◽  
Author(s):  
Fengling Zhang ◽  
Xingjia Xiang ◽  
Yuanqiu Dong ◽  
Shaofei Yan ◽  
Yunwei Song ◽  
...  

Intestinal bacterial communities form an integral component of the organism. Many factors influence gut bacterial community composition and diversity, including diet, environment and seasonality. During seasonal migration, birds use many habitats and food resources, which may influence their intestinal bacterial community structure. Hooded crane (Grus monacha) is a migrant waterbird that traverses long distances and occupies varied habitats. In this study, we investigated the diversity and differences in intestinal bacterial communities of hooded cranes over the migratory seasons. Fecal samples from hooded cranes were collected at a stopover site in two seasons (spring and fall) in Lindian, China, and at a wintering ground in Shengjin Lake, China. We analyzed bacterial communities from the fecal samples using high throughput sequencing (Illumina Mi-seq). Firmicutes, Proteobacteria, Tenericutes, Cyanobacteria, and Actinobacteria were the dominant phyla across all samples. The intestinal bacterial alpha-diversity of hooded cranes in winter was significantly higher than in fall and spring. The bacterial community composition significantly differed across the three seasons (ANOSIM, P = 0.001), suggesting that seasonal fluctuations may regulate the gut bacterial community composition of migratory birds. This study provides baseline information on the seasonal dynamics of intestinal bacterial community structure in migratory hooded cranes.


2009 ◽  
Vol 8 (1) ◽  
pp. 147-157 ◽  
Author(s):  
Paula Arroyo ◽  
Gemma Ansola ◽  
Ivan Blanco ◽  
Patricia Molleda ◽  
Estanislao de Luis Calabuig ◽  
...  

This work provides information about bacterial community structure in natural wastewater treatment systems treating different types of wastewater. The diversity and composition of bacterial communities associated with the rhizosphere of Typha latifolia and Salix atrocinerea were studied and compared among two different natural wastewater treatment systems, using the direct sequencing of the 16S ribosomal RNA codifying genes. Phylogenetic affiliations of the bacteria detected allowed us to define the main groups present in these particular ecosystems. Moreover, bacterial community structure was studied through two diversity indices. Ten identified and five non-identified phyla were found in the samples; the phylum Proteobacteria was the predominant group in the four ecosystems. The results showed a bacterial community dominated by beta-proteobacteria and a lower diversity value in the swine wastewater treatment system. The municipal wastewater treatment system presented a high diverse community in both macrophytes (Typha latifolia and Salix atrocinerea), with gamma-proteobacteria and alpha-proteobacteria, respectively, as the most abundant groups.


2011 ◽  
Vol 343-344 ◽  
pp. 351-356
Author(s):  
Xia Jia ◽  
Chun Juan Zhou

The effect of long-term elevated CO2(as open top chambers) on rhizosphere and bulk bacterial community structure in Pinus sylvestriformis seedlings field was investigated in July, August, and September. The bacterial communities were processed by Denaturing Gradient Gel Electrophoresis (DGGE) analysis of bacterial 16S rDNA fragments amplified by PCR (Polymerase Chain Reaction) from DNA extracted directly from soil. DGGE profiles from rhizosphere samples showed large changes in rhizosphere bacterial community under elevated CO2compared to ambient except for that in September. For bulk samples, bacterial community structure changed when exposed to elevated CO2in three months. With the exception of bulk samples in August, a similitude of bacterial communities structures existed between different elevated CO2concentrations by analyzing UPGMA dendrogram based on Jaccard’s coefficient.


2012 ◽  
Vol 10 (2) ◽  
pp. 244-255 ◽  
Author(s):  
T. B. Shirey ◽  
R. W. Thacker ◽  
J. B. Olson

Granular activated carbon (GAC) is an alternative filter substrate for municipal water treatment as it provides a high surface area suitable for microbial colonization. The resulting microbial growth promotes biodegradation of organic materials and other contaminants from influent waters. Here, the community structure of the bacteria associated with three GAC and two anthracite filters was examined over 12 months to monitor changes in community composition. Nearly complete 16S rRNA genes were polymerase chain reaction amplified for terminal restriction fragment length polymorphism (T-RFLP) analyses. The identity of commonly occurring peaks was determined through the construction of five representative 16S rRNA clone libraries. Based on sequence analysis, the bacterial communities associated with both anthracite and GAC filters appear to be composed of environmentally derived bacteria, with no known human pathogens. Analysis of similarity tests revealed that significant differences in bacterial community structure occurred over time, with filter substrate playing an important role in determining community composition. GAC filters exhibited the greatest degree of bacterial community variability over the sampling period, while anthracite filters showed a lower degree of variability and less change in community composition. Thus, GAC may be a suitable biologically active filter substrate for the treatment of municipal drinking water.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2367 ◽  
Author(s):  
Isabelle Laforest-Lapointe ◽  
Christian Messier ◽  
Steven W. Kembel

BackgroundThe diversity and composition of the microbial community of tree leaves (the phyllosphere) varies among trees and host species and along spatial, temporal, and environmental gradients. Phyllosphere community variation within the canopy of an individual tree exists but the importance of this variation relative to among-tree and among-species variation is poorly understood. Sampling techniques employed for phyllosphere studies include picking leaves from one canopy location to mixing randomly selected leaves from throughout the canopy. In this context, our goal was to characterize the relative importance of intra-individual variation in phyllosphere communities across multiple species, and compare this variation to inter-individual and interspecific variation of phyllosphere epiphytic bacterial communities in a natural temperate forest in Quebec, Canada.MethodsWe targeted five dominant temperate forest tree species including angiosperms and gymnosperms:Acer saccharum,Acer rubrum,Betula papyrifera,Abies balsameaandPicea glauca. For one randomly selected tree of each species, we sampled microbial communities at six distinct canopy locations: bottom-canopy (1–2 m height), the four cardinal points of mid-canopy (2–4 m height), and the top-canopy (4–6 m height). We also collected bottom-canopy leaves from five additional trees from each species.ResultsBased on an analysis of bacterial community structure measured via Illumina sequencing of the bacterial 16S gene, we demonstrate that 65% of the intra-individual variation in leaf bacterial community structure could be attributed to the effect of inter-individual and inter-specific differences while the effect of canopy location was not significant. In comparison, host species identity explains 47% of inter-individual and inter-specific variation in leaf bacterial community structure followed by individual identity (32%) and canopy location (6%).DiscussionOur results suggest that individual samples from consistent positions within the tree canopy from multiple individuals per species can be used to accurately quantify variation in phyllosphere bacterial community structure. However, the considerable amount of intra-individual variation within a tree canopy ask for a better understanding of how changes in leaf characteristics and local abiotic conditions drive spatial variation in the phyllosphere microbiome.


Author(s):  
Zufei Xiao ◽  
Beihong Zhang ◽  
Yangbao Wang ◽  
Zhinong Jin ◽  
Feng Li ◽  
...  

Abstract: Plant types and soil bacterial communities had a close relationship, understanding the profound association between them contributes to better learn bacterial ecological function for plant growth. In this study, rhizosphere soil of six different chemotype Cinnamomum camphora trees were collected, including C. bodinieri var. citralifera, [C. camphora (Linn.) Presl], camphora-type, cineole-type, linalool-type and isoborneol-type. Soil properties content and bacterial communities were analyzed. Two chemotype C. camphora, including [C. camphora (Linn.) Presl] and linalool-type, shaped similar bacterial community structure, decreased Firmcutes relative abundance. richness estimators (Chao1 index and Ace index) of [C. camphora (Linn.) Presl] were decreased compared with the others. Furthermore, soil bacterial community structure was also similar among bodinieri var. citralifera, camphora-type, cineole-type and isoborneol-type. Hence, different chemotype C. camphora altered soil nutrient and shaped rhizosphere bacterial communities.


2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Tingting Song ◽  
Hongna Li ◽  
Binxu Li ◽  
Jiaxun Yang ◽  
Muhammad Fahad Sardar ◽  
...  

Abstract Background Livestock manure is an important reservoir of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs). The bacterial community structure and diversity are usually studied using high-throughput sequencing that cannot provide direct evidence for ARB changes. Thus, little is known about the distribution of ARB, especially in the presence of different antibiotics in composting process. In this study, the fate of ARB was investigated in aerobic composting of swine manure, using chlortetracycline, sulfamethoxazole, lincomycin, and ciprofloxacin as typical antibiotics. The abundance and species of ARB were analyzed systematically to evaluate their ecological risk at different stages of composting. Results The absolute abundance of total ARB decreased, while the relative abundance increased on day 2. The relative abundance of lincomycin-resistant bacteria was higher than other ARBs during the whole composting process. The absolute abundance of four ARBs was 9.42 × 106–2.51 × 102 CFU/g (lincomycin- > chlortetracycline- > sulfamethoxazole- > ciprofloxacin- > multiple antibiotic-resistant bacteria), and they were not completely inactivated at the end of composting. Antibiotics led to a partial proliferation of ARBs including Corynebacterium, Sporosarcina, Solibacillus, and Acinetobacter. Especially, Corynebacterium, a pathogenic genus, was observed in chlortetracycline and lincomycin treatments. Conclusion Among the antibiotics studied, lincomycin showed the highest ecological risk, due to it expanded the range of lincomycin-resistant bacteria at the phyla level (Firmicutes, Actinobacteria, and Proteobacteria). The principal co-ordinates analysis indicated that the bacterial community structure was primarily associated with the composting stages rather than antibiotic types. Possible potential hosts and the related to the decrease of ARGs abundance were indicated based on the network analysis. The decrease of culturable Proteobacteria and the increase of culturable Firmicutes (Solibacillus, Bacillus) partially explained the high degradation rate of various ARGs with the progress of composting in this study. These results provided important information for the control of antibiotic resistance in composting.


Sign in / Sign up

Export Citation Format

Share Document