Search

Thise study investigated the effect of three lignocellulolytic thermophilic Bacillus strains (F11, Q1, and FP4) on lignocellulose degradation, enzymatic activities, and microbial community structure in composting. The lignin degradation rate reached 36% in the presence of the inoculant, the hemicellulose degradation rate ranged from 43% (F11) to 51% (Q1), and cellulose degradation rates reached 57% in F11 and in FP4, which were significantly higher than the control (CK). The inoculation treatment could explain 28% of the lignin degradation for all three strains. The contribution of FP4 to hemicellulose and cellulose degradation was 30% and 20%, respectively. Compared to CK, lignin peroxidase activity in the water extract of the compost had increased by 66~145% for inoculation treatments, and manganese peroxidase and laccase activity increased by 114% and 78% for Q1. The inoculation stimulated the growth of indigenous bacteria with stronger lignocellulolytic enzyme-producing ability; such shifts in microbial communities were most likely responsible for the improved lignocellulose degradation. [ABSTRACT FROM AUTHOR]

The addition of physical field enhancement measures to improve the purification effect of vertical flow artificial wetlands has gradually become popular. In this study, a vertical flow artificial wetland system reinforced by electric and magnetic fields was constructed. These fields were first optimized using finite element 3D simulation software to obtain the optimal electric and magnetic field parameters. Then, the pollutant removal effects and changes in microbial community structure were comparatively analyzed. The optimal electromagnetic field parameters (applied voltage of 15 V and applied magnetic field of 20 mT) resulted in significantly enhanced removal rates of chemical oxygen demand (COD), nitrate nitrogen (NH4+-N), total phosphorus (TP), and orthophosphorus (PO43−-P) in wastewater, with rates of 74.47%, 45.44%, 89.85%, and 90.04%, respectively. These rates were notably higher than those observed in the vertical flow artificial wetland system. The microbial community structure analysis revealed that the vertical flow constructed wetland with enhanced electric and magnetic fields exhibited (EM-VFCW) a more diverse and complex microbial community structure. Notably, the abundance of bacteria capable of removing NH4+-N and COD, including Aspergillus, Fusarium, and Actinobacteria, was significantly elevated. [ABSTRACT FROM AUTHOR]

The rhizosphere is considered a highly complex and dynamic ecosystem. Rhizosphere soil microorganisms influence the growth and development of plants by mediating the transformation and absorption of nutrients. In order to explore the microbial community composition and diversity of Alsophila spinulosa growing in different habitats. Rhizosphere samples were collected from four different habitats within the Chishui Alsophila National Nature Reserve in Guizhou Province, China. According to the high-throughput sequencing results of 16s rDNA and ITS, Proteobacteria and Ascomycota were the most abundant bacterial and fungal phyla in the rhizosphere soil of all four habitats. The alpha diversity analysis indicated that two particular habitats, Buddha Rock and Botanical Garden, harbored the highest microbial richness and diversity. LEfSe analysis revealed that Buddha Rock contained the highest relative abundance of Bacteroidetes compared to the other three study areas. Meanwhile, Tiantang Gou contained the highest relative abundance of Basidiomycota. Bacterial community composition and diversity were greatly influenced by soil pH, while fungal community composition and diversity were greatly influenced by available phosphorus, organic carbon, sucrase, and urease. The results of this study provide a scientific basis for the habitat restoration of A. spinulosa, and the improvement of the structure of the A. spinulosa rhizosphere soil microbial community. Laying a theoretical foundation for the next screening of inter-root functional flora. [ABSTRACT FROM AUTHOR]

Biochar addition plays an important role in manure composting, but its driving mechanism on microbial succession and humification process of human excreta composting is still unclear. In the present study, the mechanism of biochar addition was explored by analysing the humification process and microbial succession pattern of human excreta aerobic composting without and with 10% biochar (HF and BHF). Results indicated that BHF improved composting temperature, advanced the thermophilic phase by 1 d, increased the germination index by 49.03%, promoted the growth rate of humic acid content by 17.46%, and raised the compost product with the ratio of humic acid to fulvic acid (HA/FA) by 16.19%. Biochar regulated the diversity of fungi and bacteria, increasing the relative abundance of Planifilum, Meyerozyma and Melanocarpus in the thermophilic phase, and Saccharomonospora, Flavobacterium, Thermomyces and Remersonia in the mature phase, which accelerates the humification. Bacterial communities' succession had an obvious correlation with the total carbon, total nitrogen, and temperature (P < 0.05), while the succession of fungal communities was influenced by the HA/FA and pH (P < 0.05). This study could provide a reference for the improvement of on-site human excreta harmless by extending the thermophilic phase, and facilitating the humification in human excreta compost with biochar addition. [ABSTRACT FROM AUTHOR]

Urban complex sewage treatment plants play a vital role in modern society. The biochemical section is the core part of wastewater treatment and relies on a diverse microbial community to efficiently remove contaminants such as organics, nitrogen and phosphorus. Herein, the process water quality and microbial gene data of Urban complex sewage treatment plant L in the Yangtze River basin were systematically analyzed. The water quality at inlet and outlet the wastewater treatment plant, as well as the water quality at each stage of the treatment process, were continuously monitored, with particular focus on the biochemical section. By integrating operational and monitoring data, an assessment of the actual performance of the sewage treatment plant was conducted to identify areas for improvement. The in- let water of industrial wastewater did not have an impact on the Urban complex sewage treatment plant L, the operation of each process section was basically stable, and the effluent water quality was basically up to standard. Furthermore, the metagenomic sequencing technology is used to study the microbial community structure of activated sludge samples from the oxidation ditch of sewage treatment plant L. The results showed that there were microorganisms with different functions in the oxidation ditch. The diversity and relative abundance of microorganisms show differences between regions, and this difference reflects their ability to adapt to different environmental conditions. Through ecometabolomics analysis, the functional characteristics of microbial communities are explored. Different microbial species play their respective roles in key biochemical processes such as organic matter degradation, nitrogen removal, and phosphorus removal. By analyzing the monitoring data and studying the genes of the microbial community, a comprehensive evaluation and diagnosis of the sewage treatment plant's operation can be achieved. [ABSTRACT FROM AUTHOR]

Most research on plant–microbe interactions emphasize the effects of micronutrients on the rhizosphere microbial community structure. However, the influence of seed structures, particularly the radicle sheath, on microbial diversity at the seedling root tips under varying temperatures and humidity has been less explored. This study conducted controlled indoor experiments in the northern desert of Xinjiang to assess the radicle sheath's impact on microbial community composition, diversity, and function. The results indicated no significant changes in the Chao1 index for bacteria and fungi, but notable differences were observed in the Shannon and Simpson indices (p < 0.05). Under drought conditions, the radicle sheath significantly reduced bacterial infections without affecting fungi. Genus-level analysis showed an increased abundance of specific dominant bacterial groups when the radicle sheath was retained. NMDS analysis confirmed its significant effect on both bacterial and fungal community structures. LEfSe analysis identified 34 bacterial and 15 fungal biomarkers, highlighting the treatment's impacts on microbial taxonomic composition. Functional predictions using PICRUSt 2 revealed that the radicle sheath facilitated the conversion of CH4 to CH3OH and various nitrogen cycle processes under drought. Overall, the radicle sheath plays a crucial role in maintaining rhizosphere microbial community stability and enhancing the functions of both bacteria and fungi under drought conditions. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) pollution in soil has become a huge problem for agricultural production in China and even the world. Passivation and phytoremediation are two important remediation technologies for Cd pollution. In this study, the cadmium-contaminated and phosphorus-poor farmland soil around a mining area in Huainan was taken as the research object, and the remediation effect of biochar and phosphorus-containing materials on soil cadmium pollution was discussed. The results showed that the combined application of biochar and phosphorus-containing materials significantly reduced the pH of non-rhizosphere soil and rhizosphere soil, and increased the content of soil dissolved organic carbon (DOC). The combined application of biochar and phosphorus-containing materials significantly reduced soil pore water Cd and soil available Cd. In addition, both a single application of biochar and synergistic application of biochar and phosphorus-containing materials significantly increased the biomass of aboveground and underground parts of amaranth and soil urease and catalase activities. Phosphorus application reduced the bioavailability of Cd in soil. With the increase in phosphorus application, the content of available Cd in soil decreased significantly, and there was a certain negative correlation between Cd content and phosphorus content in plants. The abundance of beneficial microorganisms such as Ochrobactrum, Anaerolinea, Achromobacter, and Cellvibrio in soil was significantly increased after the synergistic application of biochar and phosphorus-containing materials. [ABSTRACT FROM AUTHOR]

This experiment was conducted to explore the effects of fermentation time on quality and microbial diversity of fermented monk fruit pomace. The test took the fresh monk fruit pomace as material, weighed into breathing bag and stored at ambient temperature. Fermented monk fruit pomace were taken at days 0(D0), 5(D5), 15 (D15), 35(D35), 60(D60) and 90(D90) of fermentation. Nutrient contents, fermentation indexes and microbial diversity were analyzed. The results showed as follows: the dry matter (DM) content decreased with the extension of the fermentation time, the crude protein(CP) level decreased first and then increased with the fermentation time, and the crude protein level of D35 was higher than that of D60 and D90. The fermented monk fruit pomace showed low pH and high lactic acid content at 35 days of fermentation. However, the acetic acid content of D60 and D90 were significantly increased compared with the other days. Firmicutes (65.37%) and Proteobacteria (33.37%) were the dominant bacteria at the phylum level of the fresh monk fruit pomace, and Lactobacillus (32.83%) was the dominant bacteria at the genus level. Lactobacillus (93.32%) was the dominant bacteria at the genus level of D5, and Prevotella (58.08%) of D60 was the dominant bacteria at the genus level. Correlation showed that Bifidobacterium, Clostridium_sensu_stricto_12, Dialister abundance were positively correlated with acetic acid, butyric acid, NH3-N/TN, propionic acid levels.It is concluded that monk fruit pomace is suitable for the preparation of fermented feed, and the fermentation time is 35 days. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The crude metabolic extract from plant biocontrol bacteria plays a very important role in sustainable agricultural production. These extracts help maintain healthy plants and have very important application prospects in biotechnology related to alleviating apple replant disease (ARD). In this study, Bacillus velezensis XC1 (T1), Bacillus amyloliquefaciens QSB-6 (T2), and Lactobacillus reuteri LBR (T3) were examined to characterize the ability of their crude metabolic extracts to alleviate ARD. The high-throughput sequencing data of the soil microbial community structure were analyzed in relation to LBR crude metabolic extracts, and an extensive untargeted metabolomic analysis of UHPLC-Qex active components was performed. Active LC-MS/MS revealed that the main secondary metabolites involved in the biological control exerted by L. reuteri included 3-hydroxypropionaldehyde, extracellular polysaccharides (EPS), p-hydroxybenzoic acid, and azelaic acid. These crude metabolic extracts significantly inhibited the growth of soil pathogenic fungi, reduced the abundance of Fusarium, promoted the abundance of beneficial bacteria such as Pseudomonas, and optimized the soil microbial community structure. Improved modern extraction and purification technologies will be able to offer additional insights into the mechanism of action of these secondary metabolites and enable them to be used in biological preparations to prevent and control ARD in the future, as well as to allow harmful chemical fumigants to be discontinued. [ABSTRACT FROM AUTHOR]

In the process of flue gas desulfurization and denitrification, the generation of high-sulfate wastewater containing nitrogen is a significant challenge for biological wastewater treatment. In this study, halophilic activated sludge was inoculated in a Sequencing Batch Reactor to remove nitrogen from wastewater with a high sulfate concentration (60 g/L). With the influent concentration of 180 mg/L, the removal rate of total nitrogen was more than 96.7%. The effluent ammonium nitrogen concentration was lower than 1.94 mg/L, and the effluent nitrate nitrogen and nitrite nitrogen concentrations were even lower than 0.77 mg/L. The salt tolerance of activated sludge is mainly related to the increase in the content of ectoine in microbial cells. The Specific Nitrite Oxidation Rate is quite low, while the Specific Nitrite Reduction Rate and Specific Nitrate Reduction Rate are relatively strong. In the system, there are various nitrogen metabolic processes, including aerobic nitrification, anaerobic denitrification, and simultaneous nitrification–denitrification processes. By analyzing the nitrogen metabolic mechanisms and microbial community structure of the reaction system, dominate bacteria can be identified, such as Azoarcus, Thauera, and Halomonas, which have significant nitrogen removal capabilities. [ABSTRACT FROM AUTHOR]

Saccharomyces cerevisiae can metabolize sugars to produce ethanol and secondary metabolites that contribute to the complex flavor profile of Baijiu, a traditional Chinese distilled beverage. The yeasts that contribute to Baijiu fermentation are mostly adventitious strains that show low ethanol production and stress resistance, which results in lower Baijiu yields and quality. Here, we screened S. cerevisiae strains for ethanol production and stress resistance. The best selected strain, SW4, produced a final ethanol titer of 148.1 g/L, which was 113.8% higher than the initial 69.6 g/L. Additionally, the solid-state fermentation of Baijiu with the addition of S. cerevisiae SW4 (QH) resulted in a significant increase in the relative abundance of Pediococcus and Saccharomyces at days 0–14 compared to the control (KB), which may be the main reason for the alteration of Baijiu flavor. Analysis of flavor compounds revealed that QH increased the concentration of alcohols by 44.82% relative to KB after 7 days of fermentation, as well as increasing the concentration of alcohols and esters by 13.06% and 7.11% after 28 days of fermentation. Measurement of 15 differential flavor compounds revealed that 8 were positively correlated with Saccharomyces (p ≤ 0.05), all of which are important flavor compounds contributing to the quality to Baijiu. The Baijiu yield of QH was 25.18%, which was 11.47% higher than that of KB. Overall, this study confirms the positive effects of exogenously added S. cerevisiae on the microbial community structure and flavor of Baijiu at different stages of solid-state fermentation, providing novel opportunities for improving the yield and quality of this important traditional beverage. [ABSTRACT FROM AUTHOR]

Introduction: Sichuan south-road dark tea (SSDT) is generally produced through a series of processes, including fixing, rolling, pile fermentation, and drying, with microbial action during pile fermentation playing a crucial role in determining tea quality. The air within the SSDT pile fermentation plant (SSDTPP) is considered an important source of these microbes, but research in this area has been limited. Methods: In this study, air samples from SSDTPP were collected on the 1st (SSDT1), 12th (SSDT2), and 24th (SSDT3) days of pile fermentation and comprehensively analyzed by high-throughput sequencing. Results and discussion: The results revealed the presence of 2 and 24 phyla, 9 and 49 classes, 18 and 88 orders, 28 and 153 families, 38 and 253 genera, and 47 and 90 species of fungi and bacteria, respectively, across all samples. SSDT1 and SSDT2 individually had the highest fungal and bacterial diversity, while Aspergillus was the dominant genus throughout the pile fermentation with an abundance of 34.6%, 91.17%, and 67.86% in SSDT1, SSDT2, and SSDT3, respectively. Microbial populations in SSDT1 were predominantly involved in xenobiotic biodegradation and metabolism, amino acid metabolism, the biosynthesis of other secondary metabolites, etc. However, SSDT2 exhibited a higher prevalence of human disease-related functions. SSDT3 primarily focused on the metabolism of other amino acids and carbohydrate metabolism. Additionally, 104 genera and 22 species coexisted in both SSDTPP air and piled SSDT, suggesting that frequent microbial exchange may occur between them. These findings pave the way for microbial traceability during SSDT production and provide a foundation for further functional microbial research. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】To explore the effects of phosphate-solubilizing bacteria (PSB) and their fermentation products on the properties of maize (Zea mays L.) rhizosphere soil and the composition and diversity of microbial community in lead-contaminated soil. 【Method】Based on the screening of Klebsiella pasteurii with lead-resistant and phosphate-solubilizing function, corn was cultivated in lead-contaminated soil by pot experiment. LB medium, supernatant (bacterial secretion), bacterial solution (only bacterial cells) and fermentation broth (supernatant + bacterial cells) were applied to the rhizosphere, and sterile water control was set to explore the effects of phosphate-solubilizing bacteria on the physical and chemical properties of rhizosphere soil and microbial community structure.【Result】The supernatant, bacterial liquid and fermentation liquid of K.baumannii had no significant effect on the diversity of bacterial community in maize rhizosphere, while the bacterial liquid significantly increased the Shannon index and Chao index of soil fungal community. The supernatant, bacterial liquid and fermentation liquid of the strain increased the relative abundances of heavy metal-resistant microbial groups such as Bacteroidetes and Actinobacteria, while the supernatant and fermentation liquid increased the abundances of Proteobacteria and Mortierellomycota. The supernatant increased the relative abundances of Sphingomonas, Blastococcus, Bradyrhizobium and Archaeorhizomyces. In addition, Pearson correlation analysis of differential genera in the maize rhizosphere soil showed that there were positive correlations among 7 groups of differential genera, which revealed that different microbial genera tended to form mutually beneficial symbiotic relationships. The supernatant, bacterial liquid and fermentation liquid of the strain significantly increased the activities of soil acid phosphatase (Acp) . Among them, the Acp activity of maize rhizosphere soil in the fermentation liquid treatment group was the highest (574.44 mg/g, 24-1) . The application of supernatant and bacterial liquid significantly increased the content of alkali-hydrolyzed nitrogen (AN) in the rhizosphere soil, which was 47.4% and 39.5% higher than that of the control, respectively. The three treatment groups significantly reduced the soil pH value. Through redundancy analysis (RDA), it was found that soil AN, Acp, pH value and available phosphorus (AP) were the main factors affecting the microbial community structure.【Conclusion】This study reveales that exogenous application of PSB and their fermentation products was beneficial to improving the fertility of lead-contaminated soil, and affectes the composition and structure of soil microbial community, which provides a theoretical basis for inoculating PSB and improving soil nutrients and soil microbial community structure in lead-contaminated farmland. [ABSTRACT FROM AUTHOR]

This study aimed to explore the possibility of improving the fertility of lunar soil through the reuse of resources by composting household waste and collecting composting fermentation broth. The fermentation broth was used to culture a simulated lunar soil at different concentration gradients for 30 days under aerobic and anaerobic conditions. Microbial biomass carbon and nitrogen content, typical mineral elements, and the microbial community were tested to determine whether the fertility of the lunar soil had improved. Results showed that the microorganisms in the simulated lunar soil samples successfully adhered and grew under both aerobic and anaerobic experimental conditions. The simulated lunar soil samples cultured in the anaerobic environment outperformed those in the aerobic environment regarding microbial biomass growth and water-soluble mineral elements. The study results create opportunities for the future reuse of domestic garbage on the lunar base, providing a technical basis for the in situ reuse of lunar soil resources for plant cultivation. [ABSTRACT FROM AUTHOR]

The increasing use of antibiotics in livestock poses environmental risks, leading to contamination of agricultural soils and propagation of microbial antibiotic-resistant genes (ARGs). This study examined the impacts of wood- and manure-derived biochar (BC) on antibiotic residues, ARGs, and microbial communities in sandy loam and clay loam soils amended with manure in Cynodon dactylon pastures. We hypothesized that BC amendments would influence the degradation of antibiotics and the structure of microbial communities based on their physicochemical properties and soil types. Our results demonstrated that wood BC reduced the concentrations of tetracycline and sulfonamides, particularly in sandy loam soil, due to its larger surface area and hydrophobic properties. In contrast, manure BC provided additional nutrients and supported atmospheric nitrogen-fixing microbial groups, especially in clay loam soil, while exhibiting variable efficiency in reducing antibiotic residues due to its lower surface area and higher ash content. These findings underscore the differential impacts of each BC type, emphasizing the need for tailored BC applications based on soil type to effectively mitigate antibiotic contamination and promote sustainable agricultural practices. In conclusion, wood BC was more effective in enhancing soil health by reducing antibiotic residues and improving microbial diversity, particularly in sandy loam soils, while manure BC was beneficial for nutrient cycling in clay loam soils. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici has severely threatened sustainable greenhouse tomato production. However, the effects of nutrient enrichment due to excessive fertilization on Fusarium wilt remain unclear. This study aimed to investigate the relationships among soil nutrient enrichment, microbial community structure, and the occurrence of Fusarium wilt under greenhouse conditions. This study used chemical analysis and microbiological techniques to analyze rhizosphere soil samples from greenhouse tomato production areas with varying degrees of Fusarium wilt. The results showed that, as compared with the Health group, the rhizosphere soil of Disease group has a significant nutrient enrichment, which significantly influences bacterial diversity and structure. Particularly when soil NO3−–N content exceeds 170.43 mg kg−1, there was a significant reduction in the relative abundance of key biocontrol bacteria such as Bacillus and Lysinibacillus. This reduction indirectly contributes to an increase in Fusarium oxysporum abundance, subsequently elevating the likelihood of pathogen infection. Furthermore, the Disease group also exhibited a simplified co-occurrence network with a 22.37% reduction in competitive interactions between bacteria and fungi. These changes might collectively increase the risk of tomato Fusarium wilt infection. Meanwhile, the relative abundance of bacteria carrying antibiotic resistance genes significantly increased in the Disease group, which also reduced soil resistance. Together, the results presented here not only uncover the effect of long-term excessive fertilization on the occurrence of Fusarium wilt but also advance our understanding of the interactions among soil nutrient management and microbial communities in the tomato rhizosphere, which provides a scientific basis for formulating strategies to prevent soil-borne diseases in greenhouse tomatoes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As one of the most important fertilizers in agriculture, the fate of urea-derived nitrogen (urea-N) in agricultural ecosystems has been well documented. However, little is known about the function of urea-derived carbon (urea-C) in soil ecosystems, especially which soil microorganisms benefit most from the supply of urea-C and whether the utilization of urea-C by the rhizosphere and bulk soil microorganisms is affected by irrigation regimes. To address this, a soil pot experiment was conducted using 13C-labeled urea to investigate changes in the composition of the rhizosphere and bulk soil microbial communities and differences in the incorporation of urea-derived C into the rhizosphere and bulk soil phospholipid fatty acids (PLFA) pool under flooded irrigation (FI) and water-saving irrigation (CI). Our results suggest that the size and structure of the rhizosphere and bulk soil microbial communities were strongly influenced by the irrigation regime. The CI treatment significantly increased the total amount of PLFA in both the rhizosphere and bulk soil compared to the FI treatment, but it only significantly affected the abundance of Gram-positive bacteria (G+) in the bulk soil. In contrast, shifts in the microbial community structure induced by irrigation regimes were more pronounced in the rhizosphere soil than in the bulk soil. Compared to the FI treatment, the CI treatment significantly increased the relative abundances of the G+ and Actinobacteria in the rhizosphere soil (p < 0.05). According to the PLFA-SIP, most of the labeled urea-derived C was incorporated into 16:1ω7c, 16:0 and 18:1ω7c under both treatments. Despite these general trends, the pattern of 13C incorporation into the PLFA pool differed between the treatments. The factor loadings of individual PLFAs suggested that 18:1ω7c, 16:1ω7c and 16:1ω5c were relatively enriched in urea-C in the bulk soil, while 17:1ω8c, i16:0 and 16:0 were relatively enriched in urea-C in the rhizosphere soil under different irrigation regimes. The loadings also confirmed that 10-me16:0, cy17:0 and cy19:0 were relatively enriched in urea-C under the CI treatment, whereas 14:0, a15:0 and 15:0 were relatively enriched in urea-C under the FI treatment. These results are helpful not only in revealing the interception mechanism of urea-C in soil but also in understanding the functions of key microbes in element cycles. [ABSTRACT FROM AUTHOR]

Climate change leads to an increase in both the frequency and intensity of extreme precipitation. Surface runoff generated by extreme precipitation has a significant impact on water. However, the impact of persistent precipitation on surface water quality is easy to neglect, due to its prolonged duration and lower-intensity rainfall. This study established eight sampling points within selected surface waters to observe the variation of microbial characteristics in a typical persistence precipitation event. The primary difference between Furong Lake (FL) and Chengqian Reservoir (CR) was: the concentrations of dissolved organic carbon (DOC) were 21.3 ± 0.7 and 8.3 ± 1.5 mg/L in FL and CR, respectively. The concentrations of R2A culturable bacteria and coliforms were 104.57 and 101.58 colony-forming units (CFU)/mL in FL, and were 105.46 and 102.64 CFU/mL in CR, respectively. During precipitation, the maximum increase concentrations of R2A, NA culturable bacteria, and coliforms were 100.75, 101.30, and 102.27 CFU/mL in FL, respectively. Furthermore, microbial concentration and rainfall did not increase simultaneously, and a delay phenomenon was observed in the increasing microbial concentrations. Through analyzing the concentration change trends and correlation of various water quality indicators during persistent precipitation, the significant correlation between the DOC concentration and the changes in the dominant species of microbial community structure was found in this study (p < 0.05). For example, as the DOC concentration declined, the abundance of hgcl_clade and CL500-29_marine_group increased. Consequently, although persistent precipitation might not obviously alter the water quality visibly, it could still pose potential microbial risks. [ABSTRACT FROM AUTHOR]

Long-term human activities substantially altered floodplain regions of temperate Europe. Forest management and extensive changes in hydrology greatly affected natural floodplain soil properties, in which microbes play key roles. This study aims to assess the effects of human activities through a gradient of forest management intensity on soil microbial community (SMC), its biomass, activity, and structure. Soil chemical and physical-chemical properties were used to explain the general associations and within-site variation using principal component analysis (PCA), linear regression (LR) and linear mixed-effect regression (LMER) models. It was found that forest management application, regardless of its intensity, led to significant microbial biomass reduction. PCA revealed that microbial biomass, expressed as a sum of phospholipid fatty acids along with recalcitrant carbon fraction (ROC) best explained the variability in data. LR and LMER highlighted that bacteria are affected by floodplain forest management more than fungi, and that bacterial response to pH was highly diversified. Also, pH was identified as the best predictor of SMC structure and activity but not of its size. The study calls for further investigation in SMC interactions with ROC, soil-available Fe and Mn, and the role of redox-active metals in soil organic carbon degradation.

Abstract Background and aims Continuous vegetable production under plastic tunnels faces challenges like soil degradation, increased soil-borne pathogens, and diminished eggplant yield. These factors collectively threaten the long-term sustainability of food security by diminishing the productivity and resilience of agricultural soils. This research examined the use of raw garlic stalk (RGS) waste and arbuscular mycorrhizal fungi (AMF) as a sustainable solution for these issues in eggplant monoculture. We hypothesized that the combined application of RGS waste and AMF would improve soil physicochemical properties compared to untreated soil in eggplant monoculture. The combined use of RGS and AMF was expected to suppress soil-borne pathogens, increase the abundance of soil beneficial microorganisms and alter fungal community structure. The combined application of RGS and AMF will significantly enhance eggplant yield compared to untreated plots. This study aimed to determine whether AMF and RGS, individually or in combination, can ameliorate the adverse effects of monoculture on eggplant soil. We also investigated whether these treatments could enhance eggplant yield. Methods The experiment was arranged in a completely randomized design with four treatments: AMF, RGS, and a combined treatment of AMF + RGS (ARGS), along with a control. Each treatment was replicated three times, Eggplant seedlings inoculated with AMF and treated with RGS amendments, both individually and combined. The effects on root traits, soil physicochemical properties, soil enzyme activity, and fungal community structure were investigated. Results RGS amendments and AMF inoculation improved root length, volume, and mycorrhizal colonization. The combined treatment showed the most significant improvement. RGS and AMF application increased soil nutrient availability (N, P, K) and organic matter content. Enzyme activities also increased with RGS and AMF treatments, with the combined application showing the highest activity. Soil electrical conductivity (EC) increased, while soil pH decreased with RGS and AMF amendments. Sequencing revealed a shift in the fungal community structure. Ascomycota abundance decreased, while Basidiomycota abundance increased with RGS and AMF application. The combined treatment reduced the abundance of pathogenic genera (Fusarium) and enriched beneficial taxa (Chaetomium, Coprinellus, Aspergillus). Pearson correlations supported the hypothesis that soil physicochemical properties influence fungal community composition. Conclusions This study demonstrates the potential of co-applying RGS and AMF in continuous cropping systems. It enhances soil physicochemical properties, reduces soil-borne pathogens, and promotes beneficial microbial communities and eggplant yield. This combined approach offers a sustainable strategy to address the challenges associated with eggplant monoculture under plastic tunnels.

Weathered coal has low calorific value, single utilization mode and environmental pollution. In order to broaden the utilization way of weathered coal, realize resource utilization and environmental protection, dark fermentation of weathered coal was carried out to produce biological hydrogen. Naturally weathered coals from three mining areas of Jincheng and Taiyuan in Shanxi Province and Wuhai in Inner Mongolia were selected, and the coal seam mine water was used as the source of bacteria. The feasibility of biological hydrogen production from weathered coal and the key metabolites and pathways were revealed by means of biological hydrogen production test, GC-MS, three-dimensional fluorescence and metagenomics. The results show that weathered coal in different mining areas can be converted into bio-hydrogen, and the hydrogen production of Wuhai weathered coal is the largest (10.26 mL/g), which is much higher than that of Jincheng weathered coal (5.22 mL/g). The hydrogen production system of weathered coal is in an acidic environment, and pH and COD mass concentration have certain regular changes. In the process of hydrogen production from weathered coal, the liquid organic matter is mainly composed of acids (acetic acid, propionic acid, valeric acid and butyric acid) and alcohols (2,3-butanediol, sugar alcohol and (S)-1,2-propanediol). The soluble organic matter is mainly composed of humic acid and tryptophan protein organic matter, and with the progress of fermentation, a variety of organic matter is consumed and utilized. In the process of hydrogen production from weathered coal, microorganisms are mainly dominated by Pseudomonadota and Citrobacter, and hydrogen is mainly produced by decomposing and utilizing organic acids (acetic acid, propionic acid, butyric acid, lactic acid). In the process of hydrogen production from weathered coal, the acetic acid metabolic pathway is dominated by the glycolysis pathway. The organic matter is decomposed by bacteria to produce pyruvate and then used by hydrogen-producing bacteria. Among them, alanine kinase and aldehyde ketone dehydrogenase play an important role in the process of cell metabolism to produce hydrogen. The research results reveal the potential mechanism of hydrogen production from weathered coal and provide a theoretical reference for the effective utilization of weathered coal.

The organic acids and microbial community structure of fermented grains in the dominant stacking fermentation rounds for sauce-flavor Baijiu production (i.e., the 2nd and 3rd rounds corresponding to the 3rd and 4th rounds of base liquor) were analyzed using high-performance liquid chromatography (HPLC) and high-throughput sequencing, and the interaction between them was investigated. The results revealed that lactic acid, acetic acid, and succinic acid were the primary organic acids present in fermented grains at mean values of 32.70, 4.87 and 1.93 mg/g, respectively. In total, 8 dominant bacterial genera and 7 dominant fungal genera (average relative abundance > 1%) were identified across the two fermentation rounds. The dominant bacterial genera were Virgibacillus, Kroppenstedtia and Bacillus. The dominant fungal genera were Monascus, Thermomyces and Thermoascus. Principal coordinate analysis (PCoA) revealed that there was a significant difference in the structure of bacteria community between the second and third rounds of stacking fermentation, while the difference in the structure of fungal community was not significant. Co-occurrence network analysis showed that the bacterial-fungal (55.60%), bacterial-bacterial (50.57%), and fungal-fungal (91.67%) networks were mainly positively correlated, and there were more unknown interactions between bacterial communities. Mantel test analysis showed a significantly positive correlation between acidity and bacterial community structure (P < 0.01), and succinic acid was highly correlated with both bacterial and fungal community succession (P < 0.01). Spearman’s correlation analysis revealed that the bacterial community had a more significant correlation with organic acids than the fungal community, while the fungal community showed a negative correlation with most organic acids. Nine organic acids citric acid were positively correlated with Oceanobacillus, Bacillus, and Sphingobacterium but negatively correlated with Thermoactinomyces. The results of this study can provide a theoretical basis for the production of high-quality sauce-flavor Baijiu.

The effective control of endogenous contamination of black and odorous water has become an important work in China. Phytoremediation technology is more widely used, and microbial agent method is gradually accepted due to the absence of chemical agents. In this study, microbial enhanced phytoremediation technology was used to purify black and odorous water, the removal effects of single microorganisms, single plants, and microorganisms-plant combinations on endogenous pollutants such as nitrogen and phosphorus in sediment were investigated. The results showed that the combination of microorganisms and plants exhibited better removal effect of total nitrogen and total phosphorus. Moreover, after 56 days, the removal rates of total nitrogen and total phosphorus in the sediment were 43.59% and 52.10%, respectively, which increased by 8.74% and 5.27% compared with that of single microorganisms system, and increased by 19.47% and 9.76% compared with that of single plants system. The synergistic effect of microorganisms and plants could increase the release and absorption rates of nitrogen and phosphorus in sediment, while promote nitrogen and phosphorus cycling. The high-throughput sequencing results showed that the dominant phylum in the microorganism-plant system was Proteobacteria (relative abundance 54%). The dominant phylum was Gammaproteobacteria (49%), and the dominant genus was Cavicella (10%). Microbial enhanced phytoremediation technology could provide technical support for the treatment of black and odorous sediment pollution.

The widespread use of antibiotics in pharmaceuticals and aquaculture has led to their high concentration in wastewater, posing threats to ecological stability and human health. In addressing these challenges, in our preliminary work, the embedding of microbial electrodes in a microbial electrochemical system (MES) demonstrated effective degradation of the antibiotic sulfamethoxazole (SMX) in aquatic environments. However, challenges persist, including low electron utilization efficiency and suboptimal antibiotic degradation rates. This study introduces the modification of microbial electrodes with the bimetallic oxide MnCo2O4 to enhance the electrochemical performance of the MES and the degradation efficiency of SMX. Electrochemical analysis revealed a reduction in system internal resistance by 18.99% following electrode modification. The specific capacitance of the microbial electrodes increased from 232.47 to 483.47 F/g. During operation, the MnCo2O4 -modified electrodes exhibited a 12.41% increase in average SMX degradation efficiency compared to unmodified electrodes. Microbial community structure and correlation analysis indicated a significant rise in the richness and diversity of microbes on the modified electrodes. SMX-degrading bacteria such as Acetobacterium and Trichococcus were notably enriched. This research demonstrates the effectiveness of material-modified electrodes in enhancing electron utilization in microbial electrochemistry, while also offering insights into sustainable bioremediation strategies for surface water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Successful and stable high-solid digestion was achieved in both CSTRs and PFRs. • Reduction of volatile solids was 50–54% in both reactor types. • Biogas and methane yields were significantly higher from PFRs than CSTRs. • Bacterial population was dominated by Defluviitoga in PFRs and MBA03 in CSTRs. • Stirring frequency was the likely cause for difference in microbial community. High-solid digestion (HSD) for biogas production is a resource-efficient and sustainable method to treat organic wastes with high total solids content and obtain renewable energy and an organic fertiliser, using a lower dilution rate than in the more common wet digestion process. This study examined the effect of reactor type on the performance of an HSD process, comparing plug-flow (PFR) type reactors developed for continuous HSD processes, and completely stirred-tank reactors (CSTRs) commonly used for wet digestion. The HSD process was operated in thermophilic conditions (52 °C), with a mixture of household waste, garden waste and agricultural residues (total solids content 27–28 %). The PFRs showed slightly better performance, with higher specific methane production and nitrogen mineralisation than the CSTRs, while the reduction of volatile solids was the same in both reactor types. Results from 16S rRNA gene sequencing showed a significant difference in the microbial population, potentially related to large differences in stirring speed between the reactor types (1 rpm in PFRs and 70–150 rpm in CSTRs, respectively). The bacterial community was dominated by the genus Defluviitoga in the PFRs and order MBA03 in the CSTRs. For the archaeal community, there was a predominance of the genus Methanoculleus in the PFRs, and of the genera Methanosarcina and Methanothermobacter in the CSTRs. Despite these shifts in microbiology, the results showed that stable digestion of substrates with high total solids content can be achieved in both reactor types, indicating flexibility in the choice of technique for HSD processes. [ABSTRACT FROM AUTHOR]

Abstract Crop residues and their derived biochar are frequently used for their potential to improve grain yield, soil fertility and carbon (C) sequestration. However, the effects of root are often overlooked, and the effects of chemical fertilizer (NPK) combined with root or its biochar on microbial community structure need further study. This study used 13C-labeled maize root, its biochar and soil with different fertilization for 8 years as materials and substrates. A 112-day incubation experiment was conducted to explore the effects of microbial community on the C processing. During incubation, the root-C (54.9%) mineralized significantly more than biochar-C (12.8%), while NPK addition significantly increased the root-C mineralization. Adding biochar alone did not significantly change the microbial community. Compared to the biochar treatment (BC), the root treatment (R) notably increased the contents of total phospholipid fatty acids (PLFAs), 13C-PLFA and the proportion of fungi and Gram-negative bacteria, but reduced the proportion of actinomycetes. The root mineralization was significantly correlated with the relative content of 13C-Gram-positive bacteria and 13C-fungi, while biochar mineralization was significantly correlated with the relative content of 13C-Gram-positive bacteria and 13C-actinomycetes. Notably, NPK addition significantly increased the contribution of biochar-C to PLFA-C pool, while decreasing the contribution of root-C. In summary, due to microbial adaptation to the lack of bioavailable C in biochar-amended soil, biochar can act as a buffer against the significant disturbance caused by NPK to microbial communities and native soil organic carbon (SOC), which contributes to the steady enhancement in soil C storage. Graphical Abstract

The hybrid membrane bioreactor introduces suspended biofilm carriers into the membrane bioreactor (MBR). The microbial diversity and content with the functions of carbon reduction, nitrogen removal and phosphorus accumulation were analyzed under the optimal conditions respectively to investigate the reasons and the mechanism for the differences in decontamination efficiency between HMBR and MBR through high-throughput sequencing and related analysis software. Results showed that HMBR had better pollution removal performance than MBR, and the pollutant degradation mechanisms of MBR and HMBR were different. HMBR had more active microbial communities, which were with richer species, more evenly distributed, and larger quantities. And at the same time, relevant functional bacteria were more obviously presented in HMBR, especially the addition of suspended filler brought extra increment of functional bacteria, which promoted HMBR with better pollution removal performance.

Adding corn straw to the anaerobic fermentation system of coal can significantly increase the gas production of coal-to-biomethane. However, the changes in substrate and microbial metabolism accompanying this combined fermentation are rarely studied. The Scanning Electron Microscope (SEM) test was utilized to analyze the microbial adhesion characteristics of coal and corn straw, while the X-ray Photoelectron Spectroscopy (XPS) test examined the changes in surface elements of coal. The results indicated that the optimal ratios of lean coal, weakly caking coal, and coking coal to corn straw were 2∶1, 2∶1, and 3∶1, respectively, and the corresponding methane yields were 17.28 mL/g, 12.51 mL/g, and 14.88 mL/g. The promotional effect of co-fermentation of different rank coal and straw was observed in the order of lean coal > coking coal > weakly caking coal. Microbial identification revealed that Sphaerochaeta and Proteiniphilum were the dominant bacterial genera in the mixed fermentation system, comprising 35.95% and 24.36% of the population, respectively. Additionally, Methanosarcina, Methanobacterium, and Methanoculleus emerged as the dominant archaea, constituting 49.71%, 31.83%, and 9.87%, respectively. In comparison with coking coal and weakly caking coal, the bacterial and archaeal genera, along with their associated gene functions responsible for carbohydrate metabolism in the combined fermentation broth of lean coal, coking coal, and weakly caking coal, were found to be dominant. This observation aligns with the principles governing methane production. Notably, in mixed substrate fermentation, as coal rank increased, bacterial presence on the coal surface gradually declined, while a substantial bacterial population consistently adhered to the surface of corn straw, indicating the latter's sustained advantage in degradation. After co-fermentation, the relative content of C element on the surface of coking coal and weakly caking coal decreased more significantly than that of lean coal, while the total relative content of oxygen-containing organic carbon ( C—O, C=O and O—C=O ) increased significantly, indicating that co-fermentation can promote the growth and metabolism of bacteria, so that more organic carbon can be converted into biological methane. The research results identified the effect of co-fermentation of different rank coal and corn straw at the micro level, which has reference significance for revealing the internal mechanism of co-fermentation of coal and corn straw.

Crop residues and their derived biochar are frequently used for their potential to improve grain yield, soil fertility and carbon (C) sequestration. However, the effects of root are often overlooked, and the effects of chemical fertilizer (NPK) combined with root or its biochar on microbial community structure need further study. This study used 13C-labeled maize root, its biochar and soil with different fertilization for 8 years as materials and substrates. A 112-day incubation experiment was conducted to explore the effects of microbial community on the C processing. During incubation, the root-C (54.9%) mineralized significantly more than biochar-C (12.8%), while NPK addition significantly increased the root-C mineralization. Adding biochar alone did not significantly change the microbial community. Compared to the biochar treatment (BC), the root treatment (R) notably increased the contents of total phospholipid fatty acids (PLFAs), 13C-PLFA and the proportion of fungi and Gram-negative bacteria, but reduced the proportion of actinomycetes. The root mineralization was significantly correlated with the relative content of 13C-Gram-positive bacteria and 13C-fungi, while biochar mineralization was significantly correlated with the relative content of 13C-Gram-positive bacteria and 13C-actinomycetes. Notably, NPK addition significantly increased the contribution of biochar-C to PLFA-C pool, while decreasing the contribution of root-C. In summary, due to microbial adaptation to the lack of bioavailable C in biochar-amended soil, biochar can act as a buffer against the significant disturbance caused by NPK to microbial communities and native soil organic carbon (SOC), which contributes to the steady enhancement in soil C storage. Highlights: The addition of biochar alone for 8 consecutive years did not change the composition of the microbial community structure, but the total PLFA content increased significantly compared to the control. NPK addition reduced the proportion of microbial assimilation of root-C, while increasing the proportion of microbial assimilation of biochar-C. The effect of NPK on microbial biomass is short-lived, but the effect on microbial community structure is long-lasting. Biochar has a stronger buffering effect on the drastic changes in microbial communities and native SOC caused by NPK. [ABSTRACT FROM AUTHOR]

Introduction: Inside oil and gas pipelines, native microbial communities and different solid compounds typically coexist and form mixed deposits. However, interactions between these deposits (primarily consisting of mineral phases) and microorganisms in oil and gas systems remain poorly understood. Here, we investigated the influence of magnetite (Fe3O4), troilite (FeS), and silica (SiO2) on the microbial diversity, cell viability, biofilm formation, and EPS composition of an oil-recovered multispecies consortium. Methods: An oilfield-recovered microbial consortium was grown for 2 weeks in separate bioreactors, each containing 10 g of commercially available magnetite (Fe3O4), troilite (FeS), or silica (SiO2) at 40°C ± 1°C under a gas atmosphere of 20% CO2/80% N2. Results: The microbial population formed in troilite significantly differed from those in silica and magnetite, which exhibited significant similarities. The dominant taxa in troilite was the Dethiosulfovibrio genus, whereas Sulfurospirillum dominated in magnetite and silica. Nevertheless, biofilm formation was lowest on troilite and highest on silica, correlating with the observed cell viability. Discussion: The dissolution of troilite followed by the liberation of HS- (H2S) and Fe2+ into the test solution, along with its larger particle size compared to silica, likely contributed to the observed results. Confocal laser scanning microscopy revealed that the EPS of the biofilm formed in silica was dominated by eDNA, while those in troilite and magnetite primarily contained polysaccharides. Although the mechanisms of this phenomenon could not be determined, these findings are anticipated to be particularly valuable for enhancing MIC mitigation strategies currently used in oil and gas systems. [ABSTRACT FROM AUTHOR]

Earthworms benefit plant growth and play a vital role in shaping soil microbial communities. However, how earthworms modify the soil microorganisms and thus affect plant growth is still unclear. Although fertilizers alter the assembly of microbial communities, further investigations are required to test the effect of fertilizer type on the relationship between earthworms, soil microbial communities and plants.We evaluated the role of earthworms in soil microorganisms and maize plant growth characteristics under organic or chemical fertilizers in field and greenhouse experiments. We explored the relationships between earthworms, soil microbial community and plant growth under different fertilizer types.We found that the presence of earthworms promoted plant growth, increased the amount of plant root exudates, and enhanced the connections between rhizosphere bacterial, fungal and protist communities. Both earthworms and fertilizer application significantly changed the structure of soil bacterial, fungal and protist communities. The complexity of the soil microbial community network increased under organic, compared to chemical fertilizer application. The greenhouse experiment showed that the effect of earthworms on plant growth was weakened when maize plants were grown in sterilized soil under organic or chemical fertilizers.Synthesis and applications: Our study provides solid evidence that earthworms largely depend on soil microorganisms for their effects on plants under the application of different fertilizer conditions. This may provide new insights into reducing the amounts of fertilizer used by enhancing the role of earthworms and soil microorganisms. [ABSTRACT FROM AUTHOR]

We examined the metabolic response of microbial respiration to glucose addition with the topsoil (0-10 cm) from five plantation types, including Quercus glauca, Castanopsis kawakamii, Pinus massoniana, Phoebe bournei, and Cinnamomum camphora plantations, in the Sanming Forest Ecosystem National Field Observation and Research Station in Fujian Province. The results showed that glucose addition significantly increased microbial respiration by 82.4%-349.5%, with significant difference among tree species. In the control, microbial respiration significantly correlated with microbial biomass carbon, soil organic carbon, and the fungi/bacteria ratio, indicating that microbial metabolism was regulated by soil organic carbon content and was associated with microbial biomass and community structure in the absence of labile carbon supply. In the glucose addition treatment, microbial respiration positively correlated with soil total nitrogen, dissolved organic nitrogen, and mineral nitrogen, indicating that microbial metabolism was mainly constrained by soil nitrogen content and its availability in the presence of adequate labile carbon supply. The metabolic response of microbial respiration, as indicated by the ratio of microbial respiration in the glucose addition treatment to that in the control, was primarily affected by soil carbon/nitrogen ratio, with a decrease in the ratio leading to an increase in the microbial metabolic response. Additionally, soil pH played an important role in mediating microbial metabolic response. The effect of the content and availability of soil carbon and nitrogen on microbial respiration depended on whether microbes were carbon-limited. Soil carbon content mediated microbial respiration when microbes were carbon-limited, whereas soil nitrogen content and availability mediated microbial respiration after the alleviation of microbial carbon limitation. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Vanadium-titanium magnetite tailings are bulk industrial solid wastes and can be found in the Panxi Region of Sichuan province. The utilization of vanadium-titanium magnetite tailings as soil represents a viable strategy for achieving extensive depletion, while simultaneously fostering ecological revitalization. In order to effectively reuse the stockpiled Vanadium-titanium magnetite tailings, a comprehensive analysis was conducted to assess their physicochemical attributes, microbial community composition, and mineralogical makeup. Methods: The morphologies of six heavy metals, V, Cd, Cr, Cu, Ni, and Fe, extracted from different depths of the tailings soil were extracted and analyzed using the modified European Community Bureau of Reference (BCR) sequential extraction procedure. The physicochemical indexes—such as water content, pH, available sulfur, and available potassium, of the tailings soil were analyzed. The microbial community structure was analyzed using high-throughput sequencing, and the mineral composition was analyzed using X-ray diffraction (XRD). Results and discussion: The concentrations of Ni, Cu, Cr and Cd in the vanadium-titanium magnetite tailings are all within the controllable range. The content of available phosphorus was graded as level 1 (> 40 mg/kg), the content of cation exchange capacity (CEC) was graded as level 1 (> 20 cmol (+)/kg), and the content of available sulfur was 6.91 times higher than the average value (34.3 mg/kg) of available sulfur of the 10 southern provinces of China. At the T3-D3 sample sites, the Geothermobacter genus prevailed, while Thiobacillus reigned supreme at the remaining sampling locations. The microbial populations in the tailings were primarily influenced by sulfur and iron metabolism. The X-ray diffraction (XRD) analyses showed that pyroxene, mica, cordierite, and kaolinite were the primary minerals in the tailings. Conclusion: There is a low risk of soil contamination from the utilization of vanadium and titanium magnetite tailings as an ecological reclamation substrate. Organic matter and nitrogen being the limiting indicators of soil utilization. The abundance of Actinobacteria and Bacteroidota can be appropriately intensified during soil utilization to enhance the soil nitrogen and carbon cycling performance. The chemical weathering dominated the tailings, and its maturation could be accelerated by strengthening the chemical weathering pathway of tailings. [ABSTRACT FROM AUTHOR]

The rapid increase in reactive nitrogen (N) released into the environment by human activities has notably altered the structure and composition of forest soil microbial communities (SMCs), profoundly impacting the N cycle in terrestrial ecosystems. However, the response of soil microorganisms to nitrogen addition in different seasons is not clear. This study delved into how SMCs in a subtropical region of central Yunnan, China, specifically in an evergreen broad-leaved forest (EBLF), respond to N deposition during both the dry and wet seasons. Through high-throughput sequencing, we assessed the composition and structure of SMCs under varying N addition treatments across seasons, examining their interplay with soil chemical properties, enzyme activities, and community responses. The findings revealed significant outcomes following four years of N addition in the subtropical EBLF: (1) Significant changes were observed due to the interaction between N addition and seasonal changes. Soil pH significantly decreased, indicating increased soil acidification, particularly in the dry season. Increased moisture in the wet season mitigated soil acidification. (2) In the dry season, N addition led to a decrease in microbial richness and diversity. In the wet season, N addition increased microbial richness and diversity, alleviating the downward trend observed in the dry season. (3) N addition significantly impacted the composition of soil bacterial and fungal communities. Dominant fungal genera in the wet season were particularly sensitive to N addition. (4) Seasonal changes and N addition altered soil microbial community structures. Soil chemical properties and enzyme activities significantly influenced the microbial community structure. However, due to differences in soil moisture, the key environmental factors that regulate microbial communities have changed significantly during the dry and wet seasons. This study serves as a foundation for understanding how N deposition impacts SMCs in EBLF ecosystems in subtropical regions, offering valuable insights for the scientific management of forest ecological resources amidst global change trends. [ABSTRACT FROM AUTHOR]

The synergistic remediation of heavy metal-contaminated soil by functional strains and biochar has been widely studied. However, the mechanisms by which urease-producing bacteria combine with pig manure biochar (PMB) to immobilize Cd and inhibit Cd absorption in vegetables are still unclear. In our study, the effects and mechanisms of PMB combined with the urease-producing bacterium TJ6 (TJ6 + PMB) on Cd adsorption were explored. The effects of TJ6 + PMB on the Cd content and pH of the leachate were also studied through a 56-day soil leaching experiment. Moreover, the effects of the complexes on Cd absorption and microbial mechanisms in lettuce were explored through pot experiments. The results showed that PMB provided strain TJ6 with a greater ability to adsorb Cd, inducing the generation of CdS and CdCO3, and thereby reducing the Cd content (71.1%) and increasing the pH and urease activity in the culture medium. TJ6 + PMB improved lettuce dry weight and reduced Cd absorption. These positive effects were likely due to (1) TJ6 + PMB increased the organic matter and NH4+ contents, (2) TJ6 + PMB transformed available Cd into residual Cd and decreased the Cd content in the leachate, and (3) TJ6 + PMB altered the structure of the rhizosphere bacterial and fungal communities in lettuce, increasing the relative abundances of Stachybotrys, Agrocybe, Gaiellales, and Gemmatimonas. These genera can promote plant growth, decompose organic matter, and release phosphorus. Interestingly, the fungal communities were more sensitive to the addition of TJ6 and PMB, which play important roles in the decomposition of organic matter and immobilization of Cd. In conclusion, this study revealed the mechanism by which urease-producing bacteria combined with pig manure biochar immobilize Cd and provided a theoretical basis for safe pig manure return to Cd-polluted farmland. This study also provides technical approaches and bacterial resources for the remediation of heavy metal-contaminated soil. [ABSTRACT FROM AUTHOR]

【Objective】To explore the effects of different straw returning methods on soil bacterial community in Tumochuan Plain irrigation area.【Methods】Four corn straw returning modes including subsoiling returning straw (SSR), deep spin returning straw (SCR), deep tillage returning straw (DPR), no-tillage returning straw (NTR), and farmer′s shallow rotation (CK)were the positioning tests. Soil bacterial community diversity was investigated by 16S rDNA amplicon high-throughput sequencing technology, and its correlation with soil physicochemical properties, enzyme activities were analyzed.【Results】There were significant effects in soil bacterial diversity and community composition among different straw returning treatments (P<0.05), in which, NTR treatment significantly enhanced the abundance of Gemmatimonadetes and Firmicutes (P<0.05), the abundance of Chloroflexi in DPR treatment was significantly increased (P<0.05), and the abundance of Actinobacteria was decreased. That the straw returing treatments could significantly improve the soil physicochemical properties and increase soil enzyme activities, among which SSR treatment had the most significant improvement effect (P<0.05). RDA analysis found that the main physicochemical properties that drive the composition of the soil bacterial community were alkaline hydrolysis nitrogen, available potassium, cation exchange capacity, compaction and bulk density, Arthrobacter, Gaiella, Solirorobacter, Streptomyces were susceptible to soil environmental factors.【Conclusion】The straw returning has a positive effect on the improvement of the soil biological community in the Tumochuan Plain irrigation area. [ABSTRACT FROM AUTHOR]

Simple Summary: Simple Summary: This study presents the initial findings on how rice cultivation impacts water quality and the microbial community structure in ponds where mandarin fish are being fed an artificial diet. The results indicated that rice cultivation plays a significant role in reducing nutrient salt levels in the water, thus regulating the overall aquatic environment. Furthermore, the cultivation of rice has been found to alter the composition of microbial communities in the water, leading to a decrease in diversity and affecting the abundance of bacteria involved in carbon, nitrogen, and phosphorus metabolism. The study identified Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, and Deinococcus-Thermus as the dominant bacterial phyla in ponds where mandarin fish are being fed an artificial diet. Additionally, it was observed that Proteobacteria showed a particular preference for proliferation in the aquatic environment with rice cultivation on the water surface. These results provide a valuable foundation for the potential application of aquaculture practices involving mandarin fish fed an artificial diet and rice floating beds. The culture of mandarin fish using artificial feed has been gaining increasing attention in China. Ensuring good water quality in the ponds is crucial for successful aquaculture. Recently, the trial of pond-based rice floating beds (PRFBs) in aquaculture ponds has shown promising results. This research assessed the impact of PRFBs on the microbial community structure and overall quality of the aquaculture pond, thereby enhancing our understanding of its functions. The results revealed that the PRFB group exhibited lower levels of NH4+-N, NO2−-N, NO3−-N, TN, TP, and Alk in pond water compared to the control group. The microbial diversity indices in the PRFB group showed a declining trend, while these indices were increasing in the control group. At the phylum level, there was a considerable increase in Proteobacteria abundance in the PRFB group throughout the culture period, suggesting that PRFBs may promote the proliferation of Proteobacteria. In the PRFB group, there was a remarkable decrease in bacterial populations related to carbon, nitrogen, and phosphorus metabolism, including genera Rhodobacter, Rhizorhapis, Dinghuibacter, Candidatus Aquiluna, and Chryseomicrobium as well as the CL500_29_marine_group. Overall, the research findings will provide a basis for the application of aquaculture of mandarin fish fed an artificial diet and rice floating beds. [ABSTRACT FROM AUTHOR]

The experiment aimed to study the differences in intestinal morphological structure, short-chain fatty acids, and gut microbiota among pigs with different growth rates. Fifty piglets with similar dates and body weights were selected, and determined the growth index data for all pigs at the ages of 60 and 240 days, and the average daily gain (ADG) was calculated. Four pigs with the highest ADG were selected as the high daily weight gain group (HW group), and the four pigs with the lowest ADG were selected as the low daily weight gain group (LW group). Intestinal morphology, the content of short-chain fatty acids in the intestinal contents, and differences in the microbiota were measured. The results showed that in terms of intestinal morphological structure, the relative weight of the large intestine in the HW group was significantly lower than that in the LW group (P<0.05), while the weight, length, intestinal density, and length of the small intestine were all higher than those in the LW group. In terms of short-chain fatty acids in the intestinal contents, the content of acetic acid in the ileum and colon of the HW group was significantly higher than that in the LW group (P<0.05), while the content of valeric acid in the ileum and butyric acid in the colon was significantly lower than that in the LW group (P<0.05). Alpha diversity analysis of the microbial community structure showed that the Ace index in the ileum of the HW group was significantly lower than that in the LW group (P<0.05). Microbial composition analysis showed that there were two different phyla in ileum and genus, with 14 different genera respectively. The study indicates that there is a certain correlation between the weight, length, and density of the intestine and the growth rate of pigs, the content of volatile fatty acids such as acetic acid, valeric acid, and butyric acid, as well as the gut microbiota, have a regulatory effect on the growth rate of pigs, but the specific mechanisms still need further research. [ABSTRACT FROM AUTHOR]

BACKGROUND: Baijiu brewing is a complex and multifaceted multimicrobial co‐fermentation process, in which various microorganisms interact to form an interdependent micro‐ecosystem, subsequently influencing metabolic activities and compound production. Among these microorganisms, Bacillus, an important bacterial genus in the liquor brewing process, remains unclear in its role in shaping the brewing microbial community and its functional metabolism. RESULTS: A baijiu fermentation system was constructed using B. subtilis JP1 isolated from native jiupei (grain mixture) combined with daqu (a saccharifying agent) and huangshui (a fermentation byproduct). Based on high‐throughput amplicon sequencing analysis, it was evident that B. subtilis JP1 significantly influences bacterial microbial diversity and fungal community structure in baijiu fermentation. Of these, Aspergillus and Monascus emerge as the most markedly altered microbial genera in the jiupei community. Based on co‐occurrence networks and bidirectional orthogonal partial least squares discriminant analysis models, it was demonstrated that the addition of B. subtilis JP1 intensified microbial interactions in jiupei fermentation, consequently enhancing the production of volatile flavor compounds such as heptanoic acid, butyl hexanoate and 3‐methylthiopropanol in jiupei. CONCLUSION: B. subtilis JP1 significantly alters the microbial community structure of jiupei, enhancing aroma formation during fermentation. These findings will contribute to a broader application in solid‐state fermentation. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Under a full straw returning system, the relationship between soil bacterial community diversity and straw decomposition, yield, and the combined application of slow-release nitrogen and urea remains unclear. To evaluate these effects and provide an effective strategy for sustainable agricultural production, a 2-year field positioning trial was conducted using maize as the research object. Six experimental treatments were set up: straw returning + no nitrogen fertilizer (S1N0), straw returning + slow-release nitrogen fertilizer:urea = 0:100% (S1N1), straw returning + slow-release nitrogen fertilizer:urea = 30%:70% (S1N2), straw returning + slow-release nitrogen fertilizer:urea = 60%:40% (S1N3), straw returning + slow-release nitrogen fertilizer:urea = 90%:10% (S1N4), and straw removal + slow-release nitrogen fertilizer:urea = 30%:70% (S0N2). Significant differences (p < 0.05) were observed between treatments for Proteobacteria, Acidobacteriota, Myxococcota, and Actinobacteriota at the jointing stage; Proteobacteria, Acidobacteriota, Myxococcota, Bacteroidota, and Gemmatimonadota at the tasseling stage; and Bacteroidota, Firmicutes, Myxococcota, Methylomirabilota, and Proteobacteria at the maturity stage. The alpha diversity analysis of the soil bacterial community showed that the number of operational taxonomic units (OTUs) and the Chao1 index were higher in S1N2, S1N3, and S1N4 compared with S0N2 at each growth stage. Additionally, the alpha diversity measures were higher in S1N3 and S1N4 compared with S1N2. The beta diversity analysis of the soil bacterial community showed that the bacterial communities in S1N3 and S1N4 were more similar or closely clustered together, while S0N2 was further from all treatments across the three growth stages. The cumulative straw decomposition rate was tested for each treatment, and data showed that S1N3 (90.58%) had the highest decomposition rate. At the phylum level, straw decomposition was positively correlated with Proteobacteria, Actinobacteriota, Myxococcota, and Bacteroidota but significantly negatively correlated with Acidobacteriota. PICRUSt2 function prediction results show that the relative abundance of bacteria in soil samples from each treatment differed significantly. The maize yield of S1N3 was 15597.85 ± 1477.17 kg/hm2, which was 12.80 and 4.18% higher than that of S1N1 and S0N2, respectively. In conclusion, a combination of slow-release nitrogen fertilizer and urea can enhance the straw decomposition rate and maize yield by improving the soil bacterial community and structure within a full straw returning system. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Western Sichuan Yi suancai contains a group of highly functional microorganisms in an alpine and high-altitude ecological environment. Due to its unique salt-free fermentation process, it is nutritious and has a crispy texture. Six periods were established during fermentation: day 0, day 2, day 5, day 8, day 11, and day 14. The results showed that the antioxidant capacity and organic acid content increased during the fermentation process, while the pH gradually decreased, indicating that suancai from the later periods was better for supplementing the human body with acid substances and eliminating free radicals. Twenty-six flavour compounds were identified, including alcohols, esters, ketones, and acids. Ethyl alcohol, 3-methyl-1-butanol, ethyl methanoate, and acetic acid were the main contributors to the flavour, imparting floral and fruity notes to the suancai. Five dominant bacterial genera (Lactobacillus, Leuconostoc, Weissella, Klebsiella, and unclassified_o__Lactobacillales) were identified via high-throughput sequencing during the fermentation process, and there were nine dominant fungal genera (Dipodascaceae_gen_Incertae_sedis, Mucor, Pichia, unclassified__f__Dipodascaceaet, Cyberlindnera, Diutina, Trichosporon, Saccharomycopsis, and Wickerhamomyces). Correlation analysis showed that the antioxidant capacity was positively correlated with genera such as Lactobacillus, Mucor, and Alternaria, indicating that these microorganisms have important roles in enhancing the antioxidant properties of suancai. Meanwhile, some genera, such as Microbacterium, Herbaspirillum, Mortierella, and Sampaiozyma, promote the synthesis of alcohols, esters, acids, and ketones. This study revealed the interactions between microorganisms and metabolites during the fermentation of western Sichuan Yi suancai and provided a scientific basis for further understanding the fermentation mechanism of traditional suancai and improving the fermentation process. [ABSTRACT FROM AUTHOR]

Copyright of Technology of Water Treatment is the property of Technology of Water Treatment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)