scholarly journals Composition and predictive functional analysis of bacterial communities in the surface seawater of the Changjiang Estuary

Author(s):  
Dong-Mei Wu ◽  
Jian-Xin Wang ◽  
Xiao-Hui Liu ◽  
Ying-Ping Fan ◽  
Ran Jiang ◽  
...  

The objective of this study was to characterize the structure and function of microbial communities in surface seawater from the Changjiang Estuary and adjacent areas, China. Sample water was collected at 12 sites and environmental parameters were measured. Community structure was analyzed using high-throughput sequencing of 16S rDNA genes. Predictive metagenomic approach was used to predict the function of bacterial communities. Result showed that sample site A0102 had the highest bacterial abundance and diversity. The heatmap indicated that different samples could be clustered into six groups. Phylogenetic analysis showed that Proteobacteria was the predominant phylum in all samples, followed by Bacteroidetes and Actinobacteria. Alphaproteobacteria and Gammaproteobacteria were the dominant classes. The analysis of predictive metagenomic showed carbon fixation pathways in prokaryotes, nitrogen metabolism, carbon fixation in photosynthetic organisms, photosynthesis and polycyclic aromatic hydrocarbon degradation were enriched in all samples. Redundancy analysis (RDA) identified that dissolved oxygen (DO) and PO43– concentration had positive correlations with the bacterial communities while chemical oxygen demand (COD), dissolved oxygen (DO) and PO43– concentration were significantly associated with microbial functional diversity. This study adds to our knowledge of functional and taxonomic composition of microbial communities.

2017 ◽  
Author(s):  
Dong-Mei Wu ◽  
Jian-Xin Wang ◽  
Xiao-Hui Liu ◽  
Ying-Ping Fan ◽  
Ran Jiang ◽  
...  

The objective of this study was to characterize the structure and function of microbial communities in surface seawater from the Changjiang Estuary and adjacent areas, China. Sample water was collected at 12 sites and environmental parameters were measured. Community structure was analyzed using high-throughput sequencing of 16S rDNA genes. Predictive metagenomic approach was used to predict the function of bacterial communities. Result showed that sample site A0102 had the highest bacterial abundance and diversity. The heatmap indicated that different samples could be clustered into six groups. Phylogenetic analysis showed that Proteobacteria was the predominant phylum in all samples, followed by Bacteroidetes and Actinobacteria. Alphaproteobacteria and Gammaproteobacteria were the dominant classes. The analysis of predictive metagenomic showed carbon fixation pathways in prokaryotes, nitrogen metabolism, carbon fixation in photosynthetic organisms, photosynthesis and polycyclic aromatic hydrocarbon degradation were enriched in all samples. Redundancy analysis (RDA) identified that dissolved oxygen (DO) and PO43– concentration had positive correlations with the bacterial communities while chemical oxygen demand (COD), dissolved oxygen (DO) and PO43– concentration were significantly associated with microbial functional diversity. This study adds to our knowledge of functional and taxonomic composition of microbial communities.


2020 ◽  
Vol 8 (11) ◽  
pp. 1657
Author(s):  
Abdul-Salam Juhmani ◽  
Alessandro Vezzi ◽  
Mohammad Wahsha ◽  
Alessandro Buosi ◽  
Fabio De Pascale ◽  
...  

Seaweeds are a group of essential photosynthetic organisms that harbor a rich diversity of associated microbial communities with substantial functions related to host health and defense. Environmental and anthropogenic stressors may disrupt the microbial communities and their metabolic activity, leading to host physiological alterations that negatively affect seaweeds’ performance and survival. Here, the bacterial communities associated with one of the most common seaweed, Ulva laetevirens Areshough, were sampled over a year at three sites of the lagoon of Venice affected by different environmental and anthropogenic stressors. Bacterial communities were characterized through Illumina sequencing of the V4 hypervariable region of 16S rRNA genes. The study demonstrated that the seaweed associated bacterial communities at sites impacted by environmental stressors were host-specific and differed significantly from the less affected site. Furthermore, these communities were significantly distinct from those of the surrounding seawater. The bacterial communities’ composition was significantly correlated with environmental parameters (nutrient concentrations, dissolved oxygen saturation, and pH) across sites. This study showed that several more abundant bacteria on U. laetevirens at stressed sites belonged to taxa related to the host response to the stressors. Overall, environmental parameters and anthropogenic stressors were shown to substantially affect seaweed associated bacterial communities, which reflect the host response to environmental variations.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Tahnee Manning ◽  
Arjun Venkatesh Thilagaraj ◽  
Dmitri Mouradov ◽  
Richard Piola ◽  
Clare Grandison ◽  
...  

Abstract Background Dinoflagellates are a ubiquitous and ecologically important component of marine phytoplankton communities, with particularly notable species including those associated with harmful algal blooms (HABs) and those that bioluminesce. High-throughput sequencing offers a novel approach compared to traditional microscopy for determining species assemblages and distributions of dinoflagellates, which are poorly known especially in Australian waters. Results We assessed the composition of dinoflagellate assemblages in two Australian locations: coastal temperate Port Phillip Bay and offshore tropical waters of Davies Reef (Great Barrier Reef). These locations differ in certain environmental parameters reflecting latitude as well as possible anthropogenic influences. Molecular taxonomic assessment revealed more species than traditional microscopy, and it showed statistically significant differences in dinoflagellate assemblages between locations. Bioluminescent species and known associates of HABs were present at both sites. Dinoflagellates in both areas were mainly represented by the order Gymnodiniales (66%—82% of total sequence reads). In the warm waters of Davies Reef, Gymnodiniales were equally represented by the two superclades, Gymnodiniales sensu stricto (33%) and Gyrodinium (34%). In contrast, in cooler waters of Port Phillip Bay, Gymnodiniales was mainly represented by Gyrodinium (82%). In both locations, bioluminescent dinoflagellates represented up to 0.24% of the total sequence reads, with Protoperidinium the most abundant genus. HAB-related species, mainly represented by Gyrodinium, were more abundant in Port Phillip Bay (up to 47%) than at Davies Reef (28%), potentially reflecting anthropogenic influence from highly populated and industrial areas surrounding the bay. The entire assemblage of dinoflagellates, as well as the subsets of HAB and bioluminescent species, were strongly correlated with water quality parameters (R2 = 0.56–0.92). Significant predictors differed between the subsets: HAB assemblages were explained by salinity, temperature, dissolved oxygen, and total dissolved solids; whereas, bioluminescent assemblages were explained only by salinity and dissolved oxygen, and had greater variability. Conclusion High-throughput sequencing and genotyping revealed greater diversity of dinoflagellate assemblages than previously known in both subtropical and temperate Australian waters. Significant correlations of assemblage structure with environmental variables suggest the potential for explaining the distribution and composition of both HAB species and bioluminescent species.


2020 ◽  
Vol 8 (6) ◽  
pp. 919 ◽  
Author(s):  
Huichuan Zhuang ◽  
Zhuoying Wu ◽  
Linji Xu ◽  
Shao-Yuan Leu ◽  
Po-Heng Lee

Single-stage nitrite shunt denitrification (through nitrite rather than nitrate) with low dissolved oxygen (DO) supply is a better alternative in terms of energy-efficiency, short-footprint, and low C/N-ratio requirement. This study investigates the optimal DO level with temperature effect, with saline sewage at the fixed hydraulic and solids retention times of 8 h and 8 d, respectively. Moreover, 16S rRNA gene sequencing analysis corresponding with total nitrogen (TN) and chemical oxygen demand (COD) removals in each operating condition were performed. Results showed that DO of 0.3 mg/L at 20 °C achieved over 60.7% and over 97.9% of TN and COD removal, respectively, suggesting that such condition achieved effective nitrite-oxidizing bacteria inhibition and efficient denitrification. An unexpected finding was that sulfur-reducing Haematobacter and nitrogen-fixing Geofilum and Shinella were highly abundant with the copredominance of ammonia-oxidizing Comamonas and Nitrosomonas, nitrite-oxidizing Limnohabitans, and denitrifying Simplicispira, Castellaniella, and Nitratireductor. Further, canonical correspondence analysis (CCA) with respect to the operating conditions associated with phenotype prediction via R-based tool Tax4Fun was performed for a preliminary diagnosis of microbial functionality. The effects of DO, temperature, nitrite, and nitrate in various extents toward each predominant microbe were discussed. Collectively, DO is likely pivotal in single-stage nitrite shunt denitrification, as well as microbial communities, for energy-efficient saline sewage treatment.


Author(s):  
Sheng Dong ◽  
Lijun Liu ◽  
Yuxiu Zhang ◽  
Fajun Jiang

In the drinking water industry, a common advanced treatment process is comprised of treatment with ozone, followed by biological-activated carbon (O3/BAC). However, the bacterial community formation and succession procedures associated with activated carbon have rarely been reported. In this study, the dynamics of bacterial communities at three different depths were investigated using a pilot-scale O3/BAC filter. The average chemical oxygen demand (CODMn), turbidity removal and dissolved oxygen (DO) consumption rate of the filter were 26.43%, 16.57% and 16.4% during the operation period, respectively. Bacterial communities dominated by proteobacteria and Bacteroidetes attached on activated carbon were determined by polymerase chain reaction-density gradient gel electrophoresis (PCR-DGGE). Principal component analysis (PCA) revealed that the compositions and structures of bacterial communities in different layers clustered after fluctuation. A redundancy analysis (RDA) indicated that Ramlibacter henchirensis was positively correlated to chemical oxygen demand (CODMn) removal and nitrate-N removal, and Georgfuchsia toluolica also showed a positive correlation with CODMn removal. Aquabacterium parvum and Phaeobacterium nitratireducens were positively-correlated with turbidity removal. Pedobacter glucosidilyticus and Pseudomonas sp. were associated with high dissolved oxygen (DO) consumption. These results provide insight into the succession characteristics of the bacterial community of O3/BAC treatment and the interactions of the bacterial community with filter operation performance.


2017 ◽  
Vol 15 (1) ◽  
pp. 13
Author(s):  
Arif Wibowo ◽  
Mas Tri Djoko Sunarno ◽  
Safran Makmur

Penelitian mengenai parameter fisika, kimia, dan biologi penciri habitat ikan belida (Chitala lopis) dilakukan tahun 2005 - 2006 di perairan umum daratan di Sumatera, Kalimantan, dan Jawa. Tujuan nya adalah untuk mendapatkan informasi parameter lingkungan yang menjadi karakteristik habitat ikan belida dari berbagai badan air di Jawa, Sumatera, dan Kalimantan. Metode survei dan kegiatan laboratorium digunakan dalam penelitian ini. Parameter lingkungan yang diamati meliputi suhu udara, suhu air, Total Dissolved Solid (TDS), Daya Hantar Listrik (DHL), klorofil-a, kecepatan arus, Biological Oxygen Demand (BOD), oksigen terlarut, pH, alkalinitas, CO2 bebas, kedalaman air, dan kecerahan pada 116 lokasi pengambilan yang ditentukan secara sengaja di Sungai Tulang Bawang (Provinsi Lampung), Sungai Kampar, Sungai Siak (Provinsi Riau), Sungai Musi (Provinsi Sumatera Selatan), Sungai Citarum (Provinsi Jawa Barat), Sungai Kapuas (Provinsi Kalimantan Barat), dan Waduk Riam Kanan (Provinsi Kalimantan Selatan). Analisis data menggunakan pendekatan analisis multivariabel regresi berganda Metode Backward yang didasarkan pada Analisis Komponen Utama (Principal Component Analysis) dan pembeda (Discriminant Analysis), serta korespondensi analisis (correspondency analysis). Hasil penelitian menunjukkan habitat ikan belida dapat dibedakan menjadi tiga tipe, yaitu tipe yang menyerupai sungai utama, waduk, dan anak sungai. Pembeda utama sekaligus parameter lingkungan utama adalah parameter TDS yang paling besar, dan selanjutnya parameterparameter DHL, suhu udara, klorofil-a, kecepatan arus, BOD, Oksigen terlarut, pH, alkalinitas, dan CO2 bebas menyumbang yang paling sedikit. Kehadiran plankton genus Ulothrix dan Mytilina secara tidak langsung teridentifikasi sebagai penciri habitat spesifik ikan belida. Research on physical, chemical, and biological parameters indicating specific habitat of clown knife fish (Chitala lopis) was carried out at 2005 - 2006 in inlands waters of Sumatera, Borneo, and Java. This study purposed to obtain information of environmental parameters indicating habitat characteristic of the knife fish in various inland waters bodies in Sumatera, Borneo, and Java. Survey method and laboratory activities were employed in this research. Environmental parameters observed were air temperature, water temperature, Total Dissolved Solid (TDS), conductivity, water velocity, Biological Oxygen Demand (BOD), dissolved oxygen, pH, alkalinity, free C02, water depth, and water transparancy taken on 116 sampling stations distributing in Tulang Bawang River (Lampung Province), Kampar and Siak River (Riau Province), Musi River (South Sumatera Province), Kapuas River (West Kalimantan Province), Riam Kanan Reservoar (South Kalimantan Province), and Citarum River (West Java Province). Data analysis used multivariate approach of multiple regression of Backward Method such as Principal Component Analysis, Discriminant Analysis, and Corre spondency Analysis. The results showed that the clown knife fish habitats could be divided by three types of specific habitat, namely water bodies similar with main rivers, reservoir, and tributaries. Parameter of TDS indicated the primary differentization as well as habitat characteristics of the clown knife fish.Whilst the parameters of conductivity, air temperature, chlorophyill-a, water current, BOD, dissolved oxygen, pH, alcalinity, and free CO2 contributed less significance. The existence of plankton from genus Ulothrix and Mytilina was identified indirectly as the specific habitat of the clown knife fish.


2020 ◽  
Vol 66 (1) ◽  
pp. 59-70
Author(s):  
Dan Li ◽  
Xihong Liang ◽  
Zhengwei Li ◽  
Yao Jin ◽  
Rongqing Zhou ◽  
...  

In this study, we explored the effect of chemical oxygen demand (COD) load on the nitrification and microbial communities in activated sludge isolated from an aerobic nitrifying tank. The activated sludge was cultured in three different COD groups: L-COD, 200 mg/L; M-COD, 1200 mg/L; H-COD, 4200 mg/L. The results indicated that the COD exerts a negligible effect on the nitrogen removal ability within the first 24 h. However, the nitrification rate decreased with culture time; the ammonium degradation rates were found to be 80.26%, 57.56%, and 43.43% at 72 h in the three COD groups, respectively. These values correspond to decreases of 19.40%, 41.83%, and 51.48%, respectively, in relation to those observed at 24 h. The activated sludge in the different COD groups exhibited similar community compositions after 24 h, as assessed by Illumina high-throughput sequencing, while a significant difference in the relative abundances of some organisms occurred after 48 and 72 h. Proteobacteria was the main phylum, with a relative abundance of >51.45%. The genera Aridibacter, Paracoccus, Nitrospira, and Nitrosomonas were suppressed by COD load over time. This study may contribute to our knowledge about the nitrification ability and microbial communities in activated sludge at different COD load levels.


2017 ◽  
Vol 192 ◽  
pp. 149-157 ◽  
Author(s):  
Haiyan Zhang ◽  
Liang Zhao ◽  
Yao Sun ◽  
Jianing Wang ◽  
Hao Wei

2020 ◽  
Vol 17 (10) ◽  
pp. 2875-2895
Author(s):  
Taavi Liblik ◽  
Yijing Wu ◽  
Daidu Fan ◽  
Dinghui Shang

Abstract. Multiple factors have been accused of triggering coastal hypoxia off the Changjiang Estuary, and their interactions lead to high yearly variation in hypoxia development time window and distribution extent. Two oceanographic cruises, conducted in July 2015 and August–September 2017, were complemented by river discharge, circulation simulation, remotely sensed wind, salinity and sea level anomaly data to study the dissolved oxygen (DO) depletion off the Changjiang Estuary from synoptic to interannual timescales. Intensification of the Chinese Coastal Current and Changjiang Diluted Water (CDW) spreading to the south together with coastal downwelling caused by the northerly wind was observed in the summer of 2015. This physical forcing led to a well-ventilated area in the north and a hypoxic area of 1.3×104 km2 in the south, while in 2017 the summer monsoon (southerly winds) induced offshore transport in the surface layer that caused a subsurface intrusion of Kuroshio-derived water to the shallower areas (<10 m depth) in the north and upwelling in the south. Wind-driven Ekman surface flow and reversal of the geostrophic current related to the upwelling compelled alteration of the Chinese Coastal Current. Consequently, intense hypoxia (DO down to 0.6 mg L−1) starting from 4 to 8 m depth connected to CDW and deep water intrusion in the north and coastal hypoxia linked to the upwelling in the south were observed in 2017. Distinct situations of stratification and DO distributions can be explained by wind forcing and concurrent features in surface and deep layer circulation, upwelling and downwelling events. Enhanced primary production in the upper layer of the CDW or the upwelled water determines the location and extent of DO depletion. Likewise, the pycnocline created by Kuroshio subsurface water intrusion is an essential precondition for hypoxia formation. Wind forcing largely controls the interannual change of hypoxic area location and extent. If the summer monsoon prevails, extensive hypoxia more likely occurs in the north. Hypoxia in the south occurs if the summer monsoon is considerably weaker than the long-term mean.


Sign in / Sign up

Export Citation Format

Share Document