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Polygonatum kingianum Collett & Hemsl., is one of the most important traditional Chinese medicines in China. The purpose of this study is to investigate the relationship between herb quality and microbial-soil variables, while also examining the composition and structure of the rhizosphere microbial community in Polygonatum kingianum, the ultimate goal is to provide a scientific approach to enhancing the quality of P. kingianum. Illumina NovaSeq technology unlocks comprehensive genetic variation and biological functionality through high-throughput sequencing. And in this study it was used to analyze the rhizosphere microbial communities in the soils of five P. kingianum planting areas. Conventional techniques were used to measure the organic elements, pH, and organic matter content. The active ingredient content of P. kingianum was identified by High Performance Liquid Chromatography (HPLC) and Colorimetry. A total of 12,715 bacterial and 5487 fungal Operational Taxonomic Units (OTU) were obtained and taxonomically categorized into 81 and 7 different phyla. Proteobacteria, Bacteroidetes, and Acidobacteriae were the dominant bacterial phyla Ascomycota and Basidiomycota were the dominat fungal phyla. The key predictors for bacterial community structure included hydrolysable nitrogen and available potassium, while for altering fungal community structure, soil organic carbon content (OCC), total nitrogen content (TNC), and total potassium content (TPOC) were the main influencing factors. Bryobacter and Candidatus Solibacter may indirectly increase the polysaccharide content of P. kingianum, and can be developed as potential Plant Growth Promoting Rhizobacteria (PGPR). This study has confirmed the differences in the soil and microorganisms of different origins of P. kingianum, and their close association with its active ingredients. And it also broadens the idea of studying the link between plants and microorganisms. [ABSTRACT FROM AUTHOR]

Xuanwei ham is a traditional fermented meat product in China with a unique production process and excellent-quality reputation at home and abroad. To reveal the microbial community succession of Xuanwei ham at different post-ripening times (W1-4) and its relationship with flavour formation, the microbial community, free amino acids, and volatile flavour compounds (VOCs) were analysed by high-throughput sequencing, liquid chromatography (LC), and gas chromatography–mass spectrometry (GC-MS), respectively. A total of 25 free amino acids were detected, among which W3 contained the fewest, and most were generally lower than in hams in the other three years. Fifty-nine VOCs were detected, among which 17 were esters, and the highest ester content was found in W4. Analysis of the bacterial community composition revealed that the bacterial community composition of ham samples from W3 and other years differed greatly, and at the gate level, the dominant bacterial group of Xuanwei ham from different years was Pseudomonadota. At the genus level, the most abundant genera in W1, W2, and W4 were all dominated by Sarocladium, Klebsiella, and Vibrio, with Klebsiella being the most abundant in W1. The most abundant genus in W3 was Vibrio, and the second most dominant genera were Sarocladium and Gammaretrovirus. In short, this study provides a theoretical basis for the storage, quality, and improvement of Xuanwei ham. [ABSTRACT FROM AUTHOR]

Soil copper (Cu) pollution is a serious environmental risk in the Panax notoginseng planting area. However, the effect of Cu on soil microbial metabolism and nutrient cycling in this area remains unknown. Therefore, Biolog ECO-plate and enzyme stoichiometry methods were utilized in this study to investigate the impact of exogenous Cu (control: 0 mg·kg-1; Cu100: 100 mg·kg-1; Cu400: 400 mg·kg-1; and Cu600: 600 mg·kg-1) on the metabolic function of soil microbial and nutrient limitation in the P. notoginseng soil. The results indicated that Cu100 significantly increased soil organic carbon (SOC), total phosphorus (TP), soil C:N, microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN) 9.89%, 15.65%, 17.91%, 61.87%, and 90.56% higher than the control, respectively. Moreover, the carbon source utilization ratio of carbohydrates, amino acids, and amphiphilic compounds of Cu100 also increased by 7.16%, 25.47%, and 84.68%, respectively, compared with the control. The activities of b-1,4-glucosidase, cellobiohyrolase, leucine amino peptidase, b-1,4-N-acetylglucosaminidase, and phosphatase significantly decreased with increasing Cu concentration. Soil enzyme stoichiometry showed that all treatments were limited by nitrogen (vector angle < 45°; 19.045-22.081). Cu600 led to the lowest carbon limitation (1.798) and highest carbon use efficiency (CUE:0.267). The PLS-SEM model also showed that MBC, MBN, MBP, and microbial diversity positively affected carbon and nitrogen limitation (0.654 and 0.424). Soil carbon, nitrogen, phosphorus, stoichiometric ratio, MBC, MBN, and MBP positively affected CUE (0.527 and 0.589). The microbial diversity index significantly negatively affected CUE (-1.490).Multiple linear stepwise regression analyses showed that CUE wasmainly influenced byMBC, AP, C:P, and LAP. Thus, P. notoginseng soil can benefit soil microbial carbon and nitrogen limitations at low Cu concentrations. Clarifying the metabolic activity and nutritional status of microorganisms under Cu stress can provide some theoretical basis for realizing China's comprehensive and effective management and control policies for environmental risks from metals by 2035. [ABSTRACT FROM AUTHOR]

Introduction: In recent years, the frequency and intensity of anthropogenic wildfires have drastically increased, significantly altering terrestrial ecosystems worldwide. These fires not only devastate vegetative cover but also impact soil environments and microbial communities, affecting ecosystem structure and function. The extent to which fire severity, soil depth, and their interaction influence these effects remains unclear, particularly in Pinus tabulaeformis forests. Methods: This study investigated the impact of wildfire intensity and soil stratification on soil physicochemical properties and microbial diversity within P. tabulaeformis forests in North China. Soil samples were collected from different fire severity zones (Control, Light, Moderate, High) and depths (topsoil: 0-10 cm; subsoil: 10-20 cm). Analyses included measurements of soil pH, organic carbon (SOC), total nitrogen (TN), and other nutrients. Microbial diversity was assessed using 16S rRNA gene sequencing. Results: Our findings revealed significant variations in soil pH, SOC, TN, and other nutrients with fire severity and soil depth, profoundly affecting microbial community composition and diversity. Soil pH emerged as a critical determinant, closely linked to microbial α-diversity and community structure. We found that fire severity significantly altered soil pH (p =0.001), pointing to noteworthy changes in acidity linked to varying severity levels. Topsoil microbial communities primarily differentiated between burned and unburned conditions, whereas subsoil layers showed more pronounced effects of fire severity on microbial structures. Analysis of bacterial phyla across different fire severity levels and soil depths revealed significant shifts in microbial communities. Proteobacteria consistently dominated across all conditions, indicating strong resilience, while Acidobacteriota and Actinobacteriota showed increased abundances in high-severity and light/moderate-severity areas, respectively. Verrucomicrobiota were more prevalent in control samples and decreased significantly in fire-impacted soils. Chloroflexi and Bacteroidota displayed increased abundance in moderate and high-severity areas, respectively. Correlation analyses illustrated significant relationships between soil environmental factors and dominant bacterial phyla. Soil organic carbon (SOC) showed positive correlations with total nitrogen (TN) and alkaline hydrolysable nitrogen (AN). Soil pH exhibited a negative correlation with multiple soil environmental factors. Soil pH and available phosphorus (AP) significantly influenced the abundance of the phylum Myxococcota. Soil water content (WC) significantly affected the abundances of Acidobacteriota and Actinobacteriota. Additionally, ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3--N) jointly and significantly impacted the abundance of the phylum Chloroflexi. Discussion: This study highlights the significant long-term effects of anthropogenic wildfires on soil microenvironment heterogeneity and bacterial community structure in P. tabulaeformis forests in North China, 6 years post-fire. Our findings demonstrate that fire severity significantly influences soil pH, which in turn affects soil nutrient dynamics and enhances microbial diversity. We observed notable shifts in the abundance of dominant bacterial phyla, emphasizing the critical role of soil pH and nutrient availability in shaping microbial communities. The results underscore the importance of soil stratification, as different soil layers showed varying responses to fire severity, highlighting the need for tailored management strategies. Future research should focus on long-term monitoring to further elucidate the temporal dynamics of soil microbial recovery and nutrient cycling following wildfires. Studies investigating the roles of specific microbial taxa in ecosystem resilience and their functional contributions under varying fire regimes will provide deeper insights. Additionally, exploring soil amendments and management practices aimed at optimizing pH and nutrient availability could enhance post-fire recovery processes, supporting sustainable ecosystem recovery and resilience. [ABSTRACT FROM AUTHOR]

Objective: Rhizosphere microorganisms play crucial roles in the growth and development of plants, disease resistance, and environmental adaptability. As the only wild pepper variety resource in China, domesticated Capsicum frutescens Linn. (Xiaomila) exhibits varying beneficial traits and affects rhizosphere microbial composition compared with its wild counterparts. In this study, we aimed to identify specific rhizosphere microbiome and metabolism patterns established during the domestication process. Methods: The rhizosphere microbial diversity and composition of domesticated and wild C. frutescens were detected and analyzed by metagenomics. Non-targeted metabolomics were used to explore the differences of metabolites in rhizosphere soil between wild and domesticated C. frutescens. Results: We found that the rhizosphere microbial diversity of domesticated variety was significantly different from that of the wild variety, with Massilia being its dominant bacteria. However, the abundance of certain beneficial microbes such as Gemmatimonas, Streptomyces, Rambibacter, and Lysobacter decreased significantly. The main metabolites identified in the wild variety included serylthreonine, deoxyloganic acid, vitamin C, among others. In contrast, those identified in the domesticated group were 4-hydroxy-L-glutamic acid and benzoic acid. Furthermore, the differentially enriched pathways were concentrated in tyrosine and tryptophan biosynthesis, histidine and purinederived alkaloids biosynthesis, benzoic acid family, two-component system, etc. Conclusion: This study revealed that C. frutescens established specific rhizosphere microbiota and metabolites during domestication, which has important significance for the efficient utilization of beneficial microorganisms in breeding and cultivation practices. [ABSTRACT FROM AUTHOR]

Soil erosion has become a serious ecological problem hindering the agricultural and economic development in Northeast China. Soil aggregates are basic units that regulate soil fertility and microbial activity. However, there have been few reports on the role of soil erosion in regulating the microbial diversity, multiple ecosystem services, and functions (multifunctionality) of soil aggregates. In this study, we investigated the effects of soil erosion on microbial diversity and the activities of various extracellular enzymes associated with soil aggregates by using Mollisol soil in Northeastern China at different positions of a slope, and how soil erosion affects soil multifunctionality indexes obtained by normalized calculation of soil enzyme activities. The results showed that soil erosion could reduce the physicochemical properties, soil enzyme activity, and microbial diversity of the aggregates, resulting in accumulation of aggregate nutrients and increase in microbial diversity and enzyme activity in the sedimentation area. Compared with smaller soil aggregates, larger soil aggregates had higher nutrient content, enzyme activity, and microbial diversity. However, with the intensification of soil erosion, the differences in microbial diversity and soil enzyme activities among different sizes of aggregates were reduced. Soil erosion also significantly reduced soil multifunctionality (p < 0.001). The multifunctionality of 2000–250 μm, 250–53 μm, and <53 μm aggregates respectively declined from 0.52, 0.20, and 0.08 (no erosion sites) to −0.17, −0.66, and −0.77 (heavy erosion sites). Additionally, microbial diversity was found to have a linear positive correlation with soil multifunctionality (R2 = 0.23, p < 0.01). Structural equation modeling and random forest analysis revealed that soil organic carbon and aggregate water stability are main predictors of soil multifunctionality. Furthermore, soil physicochemical properties had a greater influence on soil multifunctionality than microbial diversity. Collectively, our results demonstrate that soil erosion negatively affects the structure, resource effectiveness, and microbial activity of soil aggregates, thereby reducing to differential soil multifunctionality. [ABSTRACT FROM AUTHOR]

Background: The gut microbiota significantly influences the health and growth of red-spotted grouper (Epinephelus akaara), a well-known commercial marine fish from Fujian Province in southern China. However, variations in survival strategies and seasons can impact the stability of gut microbiota data, rendering it inaccurate in reflecting the state of gut microbiota. Which impedes the effective enhancement of aquaculture health through a nuanced understanding of gut microbiota. Inspired by this, we conducted a comprehensive analysis of the gut microbiota of wild and captive E. akaara in four seasons. Results: Seventy-two E. akaara samples were collected from wild and captive populations in Dongshan city, during four different seasons. Four sections of the gut were collected to obtain comprehensive information on the gut microbial composition and sequenced using 16S rRNA next-generation Illumina MiSeq. We observed the highest gut microbial diversity in both captive and wild E. akaara during the winter season, and identified strong correlations with water temperature using Mantel analysis. Compared to wild E. akaara, we found a more complex microbial network in captive E. akaara, as evidenced by increased abundance of Bacillaceae, Moraxellaceae and Enterobacteriaceae. In contrast, Vibrionaceae, Clostridiaceae, Flavobacteriaceae and Rhodobacteraceae were found to be more active in wild E. akaara. However, some core microorganisms, such as Firmicutes and Photobacterium, showed similar distribution patterns in both wild and captive groups. Moreover, we found the common community composition and distribution characteristics of top 10 core microbes from foregut to hindgut in E. akaara. Conclusions: Collectively, the study provides relatively more comprehensive description of the gut microbiota in E. akaara, taking into account survival strategies and temporal dimensions, which yields valuable insights into the gut microbiota of E. akaara and provides a valuable reference to its aquaculture. [ABSTRACT FROM AUTHOR]

Aim: Climate is widely understood to determine elevational patterns of soil microbial communities, whereas the effects of parental material are uncertain. Changes in the composition of parental materials along elevational transects could also affect soil microbial communities by influencing soil pH and nutrient availability. Here, we aim to illustrate the combined effects of climate and parental material on the biomass and composition of soil microbial communities along an elevational transect. Location: A subtropical forest on a karst mountain (Mt. Jinfo), China. Taxon: Bacteria and Fungi. Methods: We use phospholipid fatty acid analysis (PLFA) and DNA amplicon high‐throughput sequencing to determine biomass and diversity patterns of soil microbial communities along a subtropical elevational gradient with contrasting parental materials (limestone and clasolite). Results: We observed that the microbial communities were more diverse (α‐diversity) and productive (biomass) on limestone than on clasolite. Additionally, we found that parental material played a role in shaping the composition (β‐diversity) of soil microbial communities along the elevational gradient. The impact of climate on soil microbial communities was found to be significant, albeit relatively weak. Structural equation models provided evidence for both direct and indirect effects of climate and parental material on microbial biomass and α‐diversity along the elevational gradient. Notably, the changes in soil pH, influenced by both parental material and climate, were identified as a key factor driving these effects. Main Conclusions: Our results underline the importance of both climate and parental material variations in space‐for‐time studies investigating soil microbial communities along elevational gradients. [ABSTRACT FROM AUTHOR]

Background: Soil microbial community composition with stand development may be changed due to the variations in canopy structure, understory vegetation, root traits, edaphic conditions, and litter inputs. However, it is still uncertain to what extent these biotic and abiotic factors shape the soil microbial community composition in Chinese fir (Cunninghamia lanceolata) plantations, which are widely planted in southern China. Methods: Amplicon sequencing was used to analyze the diversity and composition of soil bacterial and fungal communities at two soil depths across four developmental stages of Chinese fir plantations. Results: Both the bacterial and fungal communities were significantly different between stand age groups. As stand aged, oligotrophic bacteria decreased in abundance while copiotrophic bacteria increased. Meanwhile, fungal functional groups connected to plants decreased in abundance while that of saprotrophic fungi significantly increased. The variance in bacterial community was mainly attributed to soil variables regarding carbon and nutrient availability, whereas the greatest fraction of fungal community dissimilarity was determined by plant-specific factors such as aboveground stand structure and tree root traits. The chemical composition of litter had a major effect on the soil fungal community, whereas the litter traits had no effect on the bacterial community. Conclusions: The potential drivers of soil fungi and bacteria differ in Chinese fir plantations. By accounting for the impacts of various environmental components, it is possible to anticipate the response of soil bacterial and fungal assemblages to forest management regime implemented in Chinese fir plantations. [ABSTRACT FROM AUTHOR]

For deep underground coal mining ecosystems, research on microbial communities and geochemical characteristics of sediments in different functional zones is lacking, resulting in the knowledge of zone-level mine water pollution prevention and control being narrow. In this study, we surveyed the geochemical distinctions and microbial communities of five typical functional zones in a representative North China coalfield, Xinjulong coal mine. The data indicated that the geochemical compounds and microbial communities of sediments showed distinguishing features in each zone. The microbial community richness and diversity were ranked as follows: surface water > rock roadways > sumps > coal roadways ≥ goafs. Canonical Correlation Analysis (CCA), Spearman correlation and co-occurrence network analysis demonstrated that microbial communities were sensitive and closely related to hydrochemical processes. The microbial community distribution in the underground mine was closely related not only to nutrient elements (i.e., C, S, P and N), but also to redox-sensitive substances (i.e., Fe and As). When it comes to mine water pollution prevention and control, the central zones are goafs. With the increase in goaf closure time, total nitrogen (TN), total organic carbon (TOC) and total sulfur (TS) decreased, but As, Fe and total phosphorus (TP) gradually increased, and the characteristic pollutant SO42− concentration in water samples decreased. Additionally, the sulfate-reducing bacteria (SRB) had relatively higher proportions in goafs, suggesting goafs were able to purify themselves. In practical engineering, in situ nitrogen injection technology used to expel oxygen and create an anaerobic environment can be implemented to enhance SRB reducing sulfate in goafs. Meanwhile, because coal mine pollution discharge generally only discharges mine water and leaves sediment underground, the pollutants can be transferred to the sediment by strengthening the relevant reactions including the heavy metal solidification and stabilization function of bacteria. [ABSTRACT FROM AUTHOR]

Purpose: Soil quality is crucial for the growth and development of tea plants. Although the tea rhizosphere microbial composition and function have been extensively studied, few comparative studies have been performed to explore the different ecological niches of tea plants' microbes and their response to current global warming. Materials and methods: In this study, we selected a typical tea plant soil located in Chibi city, Hubei Province, China and collected samples during different seasons from rhizosphere and nonrhizosphere of tea plants. Using the Microbial phospholipid fatty acid analysis method and high-throughput sequencing to analyze the functions of dominant bacterial communities and strategies for coping with different environmental pressures. Results and discussion: The results showed that 19:0 cyclo ω7c was the dominant peak in both the rhizosphere and nonrhizosphere environments in winter compared with 16:0 in both the rhizosphere and nonrhizosphere soil in summer. The composition of PLFAs and a series of derived parameters were regulated by environmental factors such as soil pH, redox potential, total organic carbon, total nitrogen and NO3−-N content. In addition, the tea plant soil microorganisms differed significantly under the different temperature stresses, with significant enrichment of Ktedonobacteria and Micrococcaceae in winter and of Gammaproteobacteria and Proteobacteria in summer. Conclusions: The rhizosphere and nonrhizosphere soil microbial communities of tea plants were co-regulated by the root secretions growth conditions of tea plants, the fertilization conditions and the temperature stress. [ABSTRACT FROM AUTHOR]

Introduction: The Sanxingdui Site in Guanghan City, Sichuan Province, China, is one of the precious heritage sites of the ancient Chinese civilization. Archaeological work at Sanxingdui is of great significance in clarifying the origins and main contents of the ancient Shu culture and the Yangtze River civilization. Since the 1920s, archaeologists have conducted extensive excavations and research at the site, with particular attention given to the large number of ivory artifacts unearthed. However, the buried ivory is influenced by soil pH, temperature, humidity, and other physical and chemical factors, along with the potential impact of microbial activities that may lead to the corrosion and decomposition of ivory. By understanding the types and activities of microorganisms, appropriate measures can be taken to protect and preserve cultural relics. Methods: Multi-point sampling of soil samples around the ivory of the three sacrificial pits at the Sanxingdui site was carried out, and strict aseptic operation was carried out during the sampling process. Subsequently, the microbial community structure and diversity in the buried ivory soil of Sanxingdui site were identified and analyzed by Illumina high-throughput sequencing technology. Results: 16S rRNA and internal transcribed spacer sequence analysis revealed significant differences in the soil microbial community structure among different sacrificial pits. The dominant bacterial phyla were the Proteobacteria, GAL15, Actinobacteriota, Bacteroidota, and Methylomirabilota. The dominant fungal phyla were Ascomycota, Mortierellomhcota, and Basidiomycota. Most dominant bacterial and fungal communities play an indispensable role in the ivory corrosion mechanism, promoting the decay and decomposition process through various means such as decomposing organic matter and producing acidic substances. Discussion: It is particularly important to take a series of measures to control microbial activity to effectively protect ivory. Our preliminary study of the mechanism of action of microorganisms on ivory in a buried environment provides a scientific basis to prevent and protect against microbial degradation in ancient ivory unearthed in Sanxingdui. Following the research results, suitable antibacterial agents tailored to the preservation environment and microbial characteristics of ancient ivory can be prepared. Ensure that the selected antibacterial agents meet safety and effectiveness requirements to maximize protection against microbial degradation of ancient ivory. [ABSTRACT FROM AUTHOR]

Fragaria nilgerrensis is a wild strawberry species widely distributed in southwest China and has strong ecological adaptability. Akihime (F. × ananassa Duch. cv. Akihime) is one of the main cultivated strawberry varieties in China and is prone to infection with a variety of diseases. In this study, high-throughput sequencing was used to analyze and compare the soil and root microbiomes of F. nilgerrensis and Akihime. Results indicate that the wild species F. nilgerrensis showed higher microbial diversity in nonrhizosphere soil and rhizosphere soil and possessed a more complex microbial network structure compared with the cultivated variety Akihime. Genera such as Bradyrhizobium and Anaeromyxobacter, which are associated with nitrogen fixation and ammonification, and Conexibacter, which is associated with ecological toxicity resistance, exhibited higher relative abundances in the rhizosphere and nonrhizosphere soil samples of F. nilgerrensis compared with those of Akihime. Meanwhile, the ammonia-oxidizing archaea Candidatus Nitrososphaera and Candidatus Nitrocosmicus showed the opposite tendencies. We also found that the relative abundances of potential pathogenic genera and biocontrol bacteria in the Akihime samples were higher than those in the F. nilgerrensis samples. The relative abundances of Blastococcus, Nocardioides, Solirubrobacter, and Gemmatimonas, which are related to pesticide degradation, and genus Variovorax, which is associated with root growth regulation, were also significantly higher in the Akihime samples than in the F. nilgerrensis samples. Moreover, the root endophytic microbiomes of both strawberry species, especially the wild F. nilgerrensis, were mainly composed of potential biocontrol and beneficial bacteria, making them important sources for the isolation of these bacteria. This study is the first to compare the differences in nonrhizosphere and rhizosphere soils and root endogenous microorganisms between wild and cultivated strawberries. The findings have great value for the research of microbiomes, disease control, and germplasm innovation of strawberry. [ABSTRACT FROM AUTHOR]

Simple Summary: The utilization of reclaimed land and enhancement of its productivity are crucial for alleviating China's food production shortage. Previous research has indicated that co-cultivating rice with frogs can enhance soil fertility. However, there is limited research on the use of integrated rice–frog farming techniques to improve soil fertility on reclaimed barren land for enhanced food production efficiency. Therefore, this study evaluated the impact of rice–frog co-cultivation on soil fertility and microbial diversity of reclaimed land. Experimental plots were established for rice monoculture, low-density rice–frog co-cultivation, and high-density rice–frog co-cultivation. The study found that during the rice maturity period, the soil fertility in the plots with high-density rice–frog co-cultivation was significantly higher compared to the rice monoculture plots. Additionally, rice–frog co-cultivation increased the soil microbial diversity and altered the structure of the microbial community compared to the rice monoculture. This research indicates that compared with rice monoculture, rice–frog co-cultivation can enhance the soil fertility and microbial diversity of reclaimed land. This study provides a theoretical basis for the construction of integrated farming models on reclaimed land, offering new perspectives and opportunities for the efficient utilization of such land. Utilizing and improving the productivity of reclaimed land are highly significant for alleviating the problem of food production shortage in China, and the integrated rice–frog farming model can improve soil fertility. However, there are few studies on the use of integrated rice–frog farming technology to improve the fertility of reclaimed land and increase its efficiency in food production. Therefore, this study was conducted to evaluate the effects of the rice–frog co-cropping mode on the soil fertility and microbial diversity of reclaimed land. A rice monoculture group (SF), low-density rice–frog co-cropping group (SD, 5000 frogs/mu, corresponds to 8 frogs/m2), and high-density rice–frog co-cropping group (SG, 10,000 frogs/mu, corresponds to 15 frogs/m2) were established and tested. The contents of total nitrogen, soil organic matter, available potassium, and available phosphorus of the soil in the SG group were significantly higher than those in the SF group (p < 0.05) in the mature stage of rice. Compared with the SF group, the SD and SG groups improved the soil microbial diversity and changed the structure of the microbial community. This study indicates that compared with the rice monoculture mode, the rice–frog co-cropping pattern can improve the soil fertility, as well as microbial diversity, of reclaimed land. [ABSTRACT FROM AUTHOR]

The Northeast China Plain (NCP) is the country's most important grain-producing area. Unraveling how bacterial communities in this region assemble and distribute according to soil type is essential for sustainable agricultural development and optimizing the precise management of soil resources. In this study, 106 soil samples were collected from three typical zonal soil types (black calcium soil (BCS), black soil (BS), and dark brown soil (DBS)) spanning from west to east in the NCP. By combining soil field surveys and high-throughput microbial sequencing analysis, we found that bacterial diversity and community structure differed significantly by soil type. Proteobacteria, Gemmatimonadetes, and Acidobacteria were enriched in BCS, BS, and DBS, respectively. Compared to BSC and DBS, BS had the highest nutrient concentration and most neutral pH values, which may recruit more diverse bacterial communities and construct a more connected ecological network. Network analysis further identified Burkholderiales, Sphingomonadales, and SC I 84 as key hubs in BS, BCS, and BCS, respectively. The majority of classified hubs consistent with the results of the linear discriminant analysis effect size belonged to the predominant biomarkers. Redundancy and Mantel test analyses revealed that the bacterial composition in various soil types showed distinctive responses to heterogeneity in soil physicochemical properties. Soil pH and TP were the primary factors shaping the soil bacterial community structure in these three soil types on the NCP. Moreover, bacterial composition and diversity were strongly related to changes in soil multifunctionality in BCS, and the relative abundances of three classes (TM1, Opitutae, and Deinococci) were the most important biotic variables for predicting BCS ecosystem multifunctionality. In summary, our results suggest that soil type variation has a strong influence in terms of shaping bacterial community structure and affecting soil multifunctionality. Correspondingly, diverse co-occurrence patterns were observed in different soil types. [ABSTRACT FROM AUTHOR]

The microbial diversity on the carposphere (berry) surface of the grape cultivar Cabernet Sauvignon grown in eight different locations/vineyards of Henan Province was determined by high-throughput sequencing of the bacterial 16S rRNA gene and fungal 18S rRNA gene. The structure of bacterial and fungal communities varied according to the sampling sites, but with some common phyla. Proteobacteria and Ascomycota were dominant/common phyla for bacteria and fungi, respectively. A total of 27 and 20 bacterial and fungal families, respectively, and 39 and 20 bacterial and fungal genera, respectively, with statistically significant differences, were found among different sampling sites. The difference for metabolic pathways of bacteria among the sampling sites existed. In addition, various abundances of enzymes from different sites might indicate that different function patterns exist in microbiota from different sites. The results revealed that locations of grape vineyards might play a significant role in shaping the microbiome, as well as the fact that vineyards can be distinguished based on the abundance of several key bacterial and fungal taxa. Overall, these findings extend our understanding of the similarities and differences in microbial community and their metabolic function on Cabernet Sauvignon grape surfaces from different geographic locations. [ABSTRACT FROM AUTHOR]

Purpose: The invasive plant Flaveria bidentis (L.) Kuntze, known as the "ecological killer", poses a significant threat to the ecosystem stability due to its strong phenotypic plasticity and high fertility. Previous studies have reported a close relationship between plant invasion and soil microbial communities. This study aimed to gain a deeper understanding of the relationship between the invasion of F. bidentis, the diversity of soil microbial communities, and soil physiochemical properties. Methods: In this study, we established a common garden experiment by planting F. bidentis and Chenopodium ficifolium Sm. separately and mixed, in Lanfang, China. We analyzed microbial communities in both bulk soil and rhizosphere soil using the high-throughput sequencing technology. Results: The results showed that F. bidentis invasion significantly increased bacterial and fungal diversities in rhizosphere soil, irrelevant with or without the existence of native plant species. Meanwhile, F. bidentis increased the content of organic matter and ammonium nitrogen (NH4+) in bulk soil and decrease the content of NH4+ in rhizosphere soil. Significant correlations were observed between nitrogen contents or acid phosphatase and specific soil microbial communities. Conclusions: These results underly that regardless of competition with native plants, the invasion of F. bidentis alters soil physicochemical properties and increases microorganism community diversity. This study establishes a theoretical foundation for further research on the invasion mechanisms of F. bidentis and provides valuable references for other studies about F. bidentis. [ABSTRACT FROM AUTHOR]

Pacific white shrimp (Penaeus vannamei) is one of the main shrimp species cultivated around the world. Despite its high yields and easy handling, water pollution from intensive shrimp cultivation remains a serious problem in China. In this study, a compound aquaculture model of P. vannamei and water spinach (Ipomoea aquatica) was used to investigate the effect of a water spinach floating raft on water quality, antioxidants, non-specific immune response, growth performance, and microbial diversity. The experimental design of this study consisted of two groups with three replicates for each, i.e., control group: aquatic monoculture (AM) system with only P. vannamei; treatment group: P. vannamei-I. aquatica raft aquaponics (AP) system with a 50% cover ratio with a water spinach floating raft. The experiment lasted for seven weeks. The results show that the concentrations of total phosphorus (TP), total nitrogen (TN), nitrate nitrogen (NO3−-N), ammonia nitrogen (NH4+-N), nitrite nitrogen (NO2−-N), and active phosphorus (AP) in the AM group were higher than those in the AP group at different sampling times. The water quality index of the AP group was better than that of the AM group, indicating that water spinach can remove the nutrients from aquaculture water bodies. The average daily gain and survival rate of shrimp in the AP group were higher than those in the AM group. The total antioxidant capacity (T-AOC), catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), and acid phosphatase (ACP) in the AP group were better than those in the AM group. The Shannon–Wiener and Simpson indices of the gut, water, and sediment of the AP system were significantly higher than those in the AM system, which implied a higher abundance of microorganisms in the AP system. These results demonstrate that the application of a water spinach floating raft in aquaponics can not only improve the water quality, but also improve the growth performance, antioxidant system, and non-specific immune responses of Pacific white shrimp, while increasing the abundance of microorganisms in the aquaculture system and improving the ecological benefits in terms of the expenditure. [ABSTRACT FROM AUTHOR]

Body size (or mass) variations and their relationships with environmental variability have been well documented for many species at the local scale, while the effects of climate, combined with soil nutrients, on plant mass in large‐scale gradient remain unclear. Herein, detailed surveys were conducted to investigate plant mass (PM, aboveground mass per plant) variations of Leymus chinensis and their relationship with environmental factors (e.g., climate, soil nutrient, and microbial diversity) at 18 wild sites along a large‐scale gradient from 114 to 124° E in northeastern China. Based on site‐by‐site analyses, the plant mass of the species varied significantly from east to west along the gradient. It initially increased, peaking at middle sites, and then dropped with the increase of drought in both dry and rainy seasons. Plant mass at the eastern end was almost equal to that at the western end and was equivalent to 1/2 and 1/3 of middle sites. The average plant mass in the rainy season was about 50% greater than that in the dry season (F1,1078 = 489.80, p <.001). The effects of environmental variables on plant mass differed in dry and rainy seasons. Mean annual temperature and temperature seasonality were the critical restrictions of plant mass in the dry season, while temperature and precipitation seasonality and soil resources (total C, Mn, Zn) had significant impacts in the rainy season (p <.05). In general, plant mass had not dropped linearly with the increase of drought along large‐scale gradient, suggesting that precipitation decrease was not the critical restriction regulating the growth and settlement of the species. [ABSTRACT FROM AUTHOR]

Cylindrospermopsis raciborskii- dominated harmful algae blooms have been reported globally in recent years. However, our understanding of the ecology of C. raciborskii in natural conditions is still poor. In this study, we collected the water samples from a C. raciborskii -blooming lake, Yilong Lake, in Yunnan province, China, and used both culture-dependent and culture-independent approaches to investigate their microbial communities and the interactions between C. raciborskii and the other bacteria. The composition and diversity of microbial communities were revealed with 16S rRNA gene high-throughput sequencing data analysis. Microbial co-occurrences analysis suggests C. raciborskii may have complex associations with other bacteria. Based on co-inoculation tests, we obtained 14 strains of bacterial strains from the water samples that exhibited either algicidal or promoting effects on a strain of C. raciborskii. Two bacterial isolates exhibited a consistent performance between co-occurrence analysis and experimental results. Effects of these bacteria-algae interspecies interactions on the bloom event are discussed. All these results may provide new insights into the C. raciborskii -dominated blooms and how its interspecies relationships with other bacteria may influence the bloom events in eutrophic waters throughout the world. [ABSTRACT FROM AUTHOR]

Simple Summary: The fall armyworm, a migratory invasive pest, poses a serious threat to the food security of major crops like maize, wheat, and rice. Understanding its adaptation mechanism to different hosts is crucial for developing effective control technology. This study examined the host fitness and gut microbial diversity of fall armyworms fed four different types of food. Based on life history parameters, pupa weight, and nutrient utilization indexes, the host fitness ranking from high to low was artificial diet, maize, wheat, and rice. Gut microbial composition and diversity varied significantly among fall armyworms fed different foods due to changes in low-abundant bacteria. Fall armyworms fed maize had the highest gut microbial diversity. The functions of gut microbes with significant abundance differences were enriched in nutrient and vitamin metabolism as well as other pathways closely related to host adaptation. Additionally, we identified five genera (Acinetobacter, Variovorax, Pseudomonas, Bacillus, and Serratia) that positively correlated with host fitness, while one genus (Rahnella) negatively correlated with it. This study reveals the potential role of gut microbes in the host adaptation of fall armyworms. The fall armyworm (FAW), Spodoptera frugiperda, seriously threatens food and cash crops. Maize, wheat, and even rice damage by FAWs have been reported in many areas of China. It is urgent to clarify the mechanism which FAWs adapt to different feeding hosts and develop effective control technologies. Two-sex life tables and 16s rDNA sequencing were used to determine the host fitness and gut microbial diversity of FAWs when fed four different food types. Considering the life history parameters, pupa weight, and nutrient utilization indexes, the host fitness of FAWs when fed different food types changed in descending order as follows: artificial diet, maize, wheat, and rice. The gut microbial composition and the diversity of FAWs when fed different food types were significantly different, and those changes were driven by low-abundant bacteria. The gut microbes of FAWs that were fed with maize had the highest diversity. The functions of the gut microbes with significant abundance differences were enriched in nutrient and vitamin metabolism and other pathways that were closely related to host adaptation. Furthermore, we identified five genera (Acinetobacter, Variovorax, Pseudomonas, Bacillus, and Serratia) and one genus (Rahnella) that were positively and negatively correlated with the host fitness, respectively. This study revealed the possible role of gut microbes in the host adaptation of FAWs. [ABSTRACT FROM AUTHOR]

The degradation of farmland in China underscores the need for developing and utilizing saline-alkali soil. Soil health relies on microbial activity, which aids in the restoration of the land's ecosystem, and hence it is important to understand microbial diversity. In the present study, two Gram-stain-positive strains HR 1-10T and J-A-003T were isolated from saline-alkali soil. Preliminary analysis suggested that these strains could be a novel species. Therefore, the taxonomic positions of these strains were evaluated using polyphasic analysis. Phylogenetic and 16S rRNA gene sequence analysis indicated that these strains should be assigned to the genus Halalkalibacter. Cell wall contained meso-2,6-diaminopimelic acid. The polar lipids present in both strains were diphosphatidyl-glycerol, phosphatidylglycerol, and an unidentified phospholipid. The major fatty acids (>10%) were anteiso-C15:0, C16:0 and iso-C15:0. Average nucleotide identity and digital DNA#x2013;DNA hybridization values were below the threshold values (95% and 70%, respectively) for species delineation. Based on the above results, the strains represent two novel species of the genus Halalkalibacter, for which the names Halalkalibacter flavus sp. nov., and Halalkalibacter lacteus sp. nov., are proposed. The type strains are HR 1-10T (=GDMCC 1.2946T = MCCC 1K08312T = JCM 36285T), and J-A-003T (=GDMCC 1.2949T = MCCC 1K08417T = JCM 36286T). [ABSTRACT FROM AUTHOR]

This paper aims to understand the influence of tourism on ecological diversity and resource structure of forest parks in order to provide guidance for the development and utilization of forest parks. Taking a forest park in China as an example, the degree of tourism impact was divided into three types, and sample plots were arranged. Plant and soil data were collected to analyze vegetation diversity, soil physicochemical properties, enzyme activities, and microbial diversity. In the highly impacted plots (HI), the importance values of dominant species increased, and its Margalef richness index and Shannon-Wiener diversity index values were significantly different from those of the moderately impacted plots (MI) and the lowly impacted plots (LI) (p < 0.05). In HI, the soil bulk density was 1.58 ± 0.15 g/cm3, the moisture content was 6.87 ± 0.56%, the pH value was 8.26 ± 0.15, the electrical conductivity was 93.29 ± 6.12 µs/cm2, and the content of organic matter was 12.77 ± 0.78 g/kg. The various enzyme activities were lower in HI, which were significantly different from MI and LI. The bacterial, fungal, and actinomycete communities of HI were less similar to those of LI. Under the influence of tourism, the vegetation diversity of the forest park decreased, soil properties changed, and microbial diversity decreased, which was not conducive to ecological stability. Therefore, it is necessary to reduce the intensity of tourism and protect the environment in the park. [ABSTRACT FROM AUTHOR]

Introduction: Soil physicochemical properties and nutrient composition play a significant role in shaping microbial communities, and facilitating soil phosphorus (P) transformation. However, studies on the mechanisms of interactions between P transformation characteristics and rhizosphere microbial diversity in Pdeficient soils on longer time scales are still limited. Methods: In this study, rhizosphere soils were collected from a pure plantation of Parashorea chinensis (P. chinensis) at six stand ages in the subtropical China, and the dynamic transformation characteristics of microbial diversity and P fractions were analyzed to reveal the variation of their interactions with age. Results: Our findings revealed that the rhizosphere soils across stand ages were in a strongly acidic and P-deficient state, with pH values ranging from 3.4 to 4.6, and available P contents ranging from 2.6 to 7.9 mg·kg-1. The adsorption of P by Fe3+ and presence of high levels of steady-state organic P highly restricted the availability of P in soil. On long time scales, acid phosphatase activity and microbial biomass P were the main drivers of P activation. Moreover, pH, available P, and ammonium nitrogen were identified as key factors driving microbial community diversity. As stand age increased, most of the nutrient content indicators firstly increased and then decreased, the conversion of other forms of P to bio-available P became difficult, P availability and soil fertility began to decline. However, bacteria were still able to maintain stable species abundance and diversity. In contrast, stand age had a greater effect on the diversity of the fungal community than on the bacteria. The Shannon and Simpson indices varied by 4.81 and 0.70 for the fungi, respectively, compared to only 1.91 and 0.06 for the bacteria. Microorganisms play a dominant role in the development of their relationship with soil P. Discussion: In conclusion, rhizosphere microorganisms in P. chinensis plantations gradually adapt to the acidic, low P environment over time. This adaptation is conducive to maintaining P bioeffectiveness and alleviating P limitation. [ABSTRACT FROM AUTHOR]

Global warming has contributed to shifts in precipitation patterns and increased plant productivity, resulting in a significant increase in litter input into the soils. The enhanced litter input, combined with higher levels of precipitation, may potentially affect soil microbial communities. This study aims to investigate the effects of litter input and increased precipitation on soil microbial biomass, community structure, and diversity in a temperate meadow steppe in northeastern China. Different levels of litter input (0%, +30%, +60%) and increased precipitation (0%, +15%, +30%) were applied over a three-year period (2015-2017). The results showed that litter input significantly increased the biomass of bacteria and fungi without altering their diversity, as well as the ratio of bacterial to fungal biomass. Increased precipitation did not have a notable effect on the biomass and diversity of bacteria and fungi, but it did increase the fungal-to-bacterial biomass ratio. However, when litter input and increased precipitation interacted, bacterial diversity significantly increased while the fungal-to-bacterial biomass ratio remained unchanged. These findings indicate that the projected increases in litter and precipitation would have a substantial impact on soil microbial communities. In energy-and water-limited temperate grasslands, the additional litter inputs and increased precipitation contribute to enhanced nutrient and water availability, which in turn promotes microbial growth and leads to shifts in community structure and diversity. [ABSTRACT FROM AUTHOR]

Insects harbor a remarkable diversity of gut microbiomes critical for host survival, health, and fitness, but the mechanism of this structured symbiotic community remains poorly known, especially for the insect group consisting of many closely related species that inhabit the Qinghai‐Tibet Plateau. Here, we firstly analyzed population‐level 16S rRNA microbial dataset, comprising 11 Parnassius species covering 5 subgenera, from 14 populations mostly sampled in mountainous regions across northwestern‐to‐southeastern China, and meanwhile clarified the relative importance of multiple factors on gut microbial community structure and evolution. Our findings indicated that both host genetics and larval host plant modulated gut microbial diversity and community structure. Moreover, the effect analysis of host genetics and larval diet on gut microbiomes showed that host genetics played a critical role in governing the gut microbial beta diversity and the symbiotic community structure, while larval host plant remarkably influenced the functional evolution of gut microbiomes. These findings of the intimate insect–microbe–plant interactions jointly provide some new insights into the correlation among the host genetic background, larval host plant, the structure and evolution of gut microbiome, as well as the mechanisms of high‐altitude adaptation in closely related species of this alpine butterfly group. [ABSTRACT FROM AUTHOR]

Background: Poyang Lake is the largest freshwater lake in China, and there are several studies on the composition and diversity of bacteria in Poyang Lake, while few quantitative studies were carried out on the response of the bacterial community to environmental factors during the extreme flood season in Poyang Lake. Methods: The connected-lake heterogeneity of bacterial community composition (BCC) was investigated in Poyang Lake during the flood season in 2020. Illumina high-throughput sequencing technology was used in this study. Results: The bacterial community structure in the water was different from that in the sediment of Poyang Lake during extreme flood seasons. The bacterial diversity in water was much lower than that in sediment. In the water column, the dominant phyla were Actinobacteriota, while the composition of bacteria in sediment was more complex than that in water, and the dominant phyla in sediment were Proteobacteria, Chloroflexi, Acidobacteriota, and Actinobacteriota. The bacterial diversity in the water of Poyang Lake showed seasonal dynamics, while no seasonal variation of bacterial communities in sediment was observed. The bacterial community structure in the sediment from the two bays and channel areas of Poyang Lake can be distinguished from each other. The microbial diversity in sediment gradually increased from the Sancha Bay to the Zhouxi Bay and then to the channel, but the total nitrogen (TN) concentration in sediment (STN) and the total phosphorus (TP) concentration in sediment (STP) showed opposite trends. This might be due to the anthropogenic disturbances from the extreme flood. The bacterial community structure in, water column was significantly correlated with WT, NH4-N, STP, SOM, Chl a, DO, TP, and Eh, while the bacterial community structure in sediment was significantly correlated with SOM and STP. Conclusion: The bacterial community structure in water was greatly different from that in sediment in Poyang Lake during extreme flood seasons. The bacterial community structure in the water column was not only sensitive to the geochemical characteristics of the water but also affected by some nutrient concentrations in the sediment. During the wet seasons, bacterial diversity was only affected by SOM and STP. [ABSTRACT FROM AUTHOR]

Revealing the mechanisms underlying soil microbial community assembly is a fundamental objective in molecular ecology. However, despite increasing body of research on overall microbial community assembly mechanisms, our understanding of subcommunity assembly mechanisms for different prokaryotic and fungal taxa remains limited. Here, soils were collected from more than 100 sites across southwestern China. Based on amplicon high‐throughput sequencing and iCAMP analysis, we determined the subcommunity assembly mechanisms for various microbial taxa. The results showed that dispersal limitation and homogenous selection were the primary drivers of soil microbial community assembly in this region. However, the subcommunity assembly mechanisms of different soil microbial taxa were highly variable. For instance, the contribution of homogenous selection to Crenarchaeota subcommunity assembly was 70%, but it was only around 10% for the subcommunity assembly of Actinomycetes, Gemmatimonadetes and Planctomycetes. The assembly of subcommunities including microbial taxa with higher occurrence frequencies, average relative abundance and network degrees, as well as wider niches tended to be more influenced by homogenizing dispersal and drift, but less affected by heterogeneous selection and dispersal limitation. The subcommunity assembly mechanisms also varied substantially among different functional guilds. Notably, the subcommunity assembly of diazotrophs, nitrifiers, saprotrophs and some pathogens were predominantly controlled by homogenous selection, while that of denitrifiers and fungal pathogens were mainly affected by stochastic processes such as drift. These findings provide novel insights into understanding soil microbial diversity maintenance mechanisms, and the analysis pipeline holds significant value for future research. [ABSTRACT FROM AUTHOR]

In recent years, the Sanjiang Plain has experienced drastic human activities, which have dramatically changed its ecological environment. Soil microorganisms can sensitively respond to changes in soil quality as well as ecosystem function. In this study, we investigated the changes in soil microbial community diversity and composition of three typical land use types (forest, wetland and cropland) in the Sanjiang Plain using phospholipid fatty acid analysis (PLFA) technology, and 114 different PLFA compounds were identified. The results showed that the soil physicochemical properties changed significantly (p < 0.05) among the different land use types; the microbial diversity and abundance in cropland soil were lower than those of the other two land use types. Soil pH, soil water content, total organic carbon and available nitrogen were the main soil physico-chemical properties driving the composition of the soil microbial community. Our results indicate that the soil microbial community response to the three different habitats is complex, and provide ideas for the mechanism by which land use changes in the Sanjiang Plain affect the structure of soil microbial communities, as well as a theoretical basis for the future management and sustainable use of the Sanjiang plain, in the northeast of China. [ABSTRACT FROM AUTHOR]

Volcanic lava is an excellent model of primary succession, in which basalt-associated microorganisms drive the cycling of different elements such as nitrogen, carbon, and other nutrients. Microbial communities in volcanic soils are of particular interest for study on the emergence and evolution of life within special and extreme conditions. The initial processes of colonization and subsequent rock weathering by microbial communities are still poorly understood. We analyzed the soil bacterial and fungal communities and diversities associated with lava (LBL) and kipuka (BK) sites in Wudalianchi using 16S and ITS rRNA Illumina Miseq sequencing techniques. The results showed that soil physical and chemical properties (pH, MC, TOC, TN, TP, AP, DOC, and DON) significantly differed between LBL and BK. The Shannon, Ace, and Pd indexes of fungi in the two sites showed a significant difference (p < 0.05). The dominant bacterial phyla forming communities at LBL and BK sites were Acidobacteria, Proteobacteria, Actinobacteria, and Basidiomycota, and their differences were driven by Gemmatimonadetes and Verrucomicrobia. The dominant fungal phyla of LBL and BK sites were Ascomycota, Zygomycota, and Rozellomcota, which differed significantly between the two sites. The microbial communities showed extremely significant differences (p < 0.05), with MC, pH, and nitrogen being the main influencing factors according to RDA/CCA and correlation analysis. Microbial functional prediction analysis across the two sites showed that the relative abundance of advantageous functional groups was significantly different (p < 0.05). The combined results drive us to conclude that the volcanic soil differences in the deposits appear to be the main factor shaping the microbial communities in Wudalianchi (WDLC) volcanic ecosystems. [ABSTRACT FROM AUTHOR]

The mechanisms underpinning the soil microbial community assembly are important, particularly in the fragile karst forest ecosystem. Despite such significance, relevant topics remain limited. We investigated a typical karst area, the Maolan National Nature Reserve in China. For this purpose, 30 forest dynamics plots were established on three restoration gradients in degraded karst forests, namely shrub, pioneer tree, and climax communities. Using vegetation surveys, we explored the diversity patterns, driving factors, and community assembly of the soil microbial communities during the restoration of degraded karst forest ecosystems. In addition, the soil physicochemical properties and macrogenomic sequencing data were examined. One-way analysis of variance and principal coordinates analysis showed no significant changes in soil microbial α-diversity during restoration, and the opposite pattern was observed for β-diversity. Variation partitioning analysis revealed that the combined effect of both soil microbial β-diversity and soil was significant (28% and 32% for bacteria and fungi, respectively). Pearson correlation analyses showed that plant species diversity and soil multifunctionality correlated significantly with soil microbial β-diversity. In contrast, the direct effect of plants was smaller (2% and 3% for bacteria and fungi, respectively). According to the dispersal–niche continuum index, stochastic processes were responsible for the assembly of the bacterial and fungal soil microbial communities. During restoration, the dominant influence of stochastic effects on the assembly of bacterial communities intensified. In contrast, the reverse tendency was observed in soil fungi. The investigation of the diversity pattern of soil microbial communities and their assembly can provide theoretical references for the restoration of degraded ecosystems. [ABSTRACT FROM AUTHOR]

Microbial communities associated with seagrass beds play a crucial role in maintaining the balance of seagrass ecosystems. However, the driving mechanisms behind the structure and functional succession of seagrass microbial communities are still unclear despite the close interaction between seagrass and surrounding microorganisms. To enhance our knowledge of the diversity and functional characteristics of microbial communities in seagrass beds, we employed 16S rRNA gene amplicon sequencing to investigate bacterial communities in seagrass leaves, roots, seawater, and sediments in Caofeidian Zostera marina seagrass beds of Hebei Province, Northern China. Our results highlighted that specific types of bacteria were enriched in different sample compartments, indicating the importance of habitat in influencing microbial diversity and community structure in seagrass bed ecosystems. Notably, the microbial community structure of seagrass leaves and roots showed more similarity to that found in seawater and sediments. Among all the samples, the phylum Pseudomonadota exhibited the highest relative abundance, particularly in sediment samples where they accounted for over 95% of the total bacterial population. In addition, the enrichment of Vibrio, an opportunistic pathogen in several plant samples, alerted us to seagrass and its surrounding marine environments. Finally, functional predictions of microbial communities using PICRUSt2 revealed variations in microbial functions, indicating specific metabolic preferences of microbial communities in different natural environments. The present research sheds light on the mechanisms underlying microbial community succession and their ecological function in seagrass beds. [ABSTRACT FROM AUTHOR]

Background: The fermented wax gourd, often referred to as "smelly wax gourd," is a traditional food that undergoes natural fermentation. It's a staple in eastern China and is recognized as Ningbo's "city-fermented food." Characterized by its distinct putrid flavor and soft texture, its safety, nutritional aspects, and sensory attributes have not been extensively studied. Methods: In this research, the microbial community and flavor components of fermented wax gourd during its traditional fermentation were analyzed. The safety and impact on the gut microbiota were also assessed by administering it to healthy and pseudo-germ-free mice. Results: The findings revealed that organic acids primarily contribute to the gourd's flavor during fermentation. The aroma reminiscent of fruits is due to 2-methyl-butyric acid, while butyric, pentanoic, caproic, and octanoic acids are responsible for their characteristic smelly taste. In the fermentation of traditional foods, the abundance of substances and open fermentation contribute to the diversity of microorganisms in the system, and the reproduction and metabolism of microorganisms drive the fermentation of foods. From the results of this study, the flavor peaks on the 10th day of fermentation. Predominant microbes include Lactobacillus fermentum, Streptococcus equinus, Fusobacterium perfoetens, Weissella confusa, and Lactobacillus plantarum. Notably, Lactobacillus was the most abundant probiotic in the early fermentation stages. The "smelly" taste of smelly wax gourd was mainly derived from butyric acid, valeric acid, caproic acid, caprylic acid, p-methylphenol and other compounds, and the abundance of Caldicoprobacter algeriensis, Mariniphaga anaerophila, Streptococcus equi and Lactobacillus were significantly correlated with 4 of the above 5 acids. These four bacteria may contribute more to the "smelly" taste of smelly wax gourd. In the study, compared with the control group (CONT), the abundance of Helicobacter ganmani, H. Chanicola, Lactobacillus animalis, Lactobacillus gadi and Lactobacillus reuteri decreased in mice groups treated with anti-biological pretreatment followed by gavage of smelly wax gourd (A.SWG) and the smelly wax gourd (SWG) groups. Conversely, Muribaculum intestinale, Prevotellamassilia timonensis, Alistipes putredinis, Kineothrix alysoides and Clostridium indolis' abundance of increases. Mice that underwent fecal microbiota transplantation (FMT) exhibited a higher abundance of probiotics like Bifidobacterium animalis, Bifidobacterium pseudolongum, Lactobacillus johnsonii, and others compared to the fecal culture microbiota transplantation (CMT) group. However, the CMT group had a higher presence of fermented and Royce lactobacilli. Implication: Consuming fermented wax gourd can enhance the presence of beneficial probiotics and reduce pathogenic Helicobacter sp. in the mouse gut. Both Lactobacillus sp. and Bifidobacterium sp. showed increased abundance post fecal microbiota and fecal culture microbiota transplantation. [ABSTRACT FROM AUTHOR]

The gut microbiota of rodents is essential for survival and adaptation and is susceptible to various factors, ranging from environmental conditions to genetic predispositions. Nevertheless, few comparative studies have considered the contribution of species identity and geographic spatial distance to variations in the gut microbiota. In this study, a random sampling survey encompassing four rodent species (Apodemus agrarius, Cricetulus barabensis, Tscherskia triton and Rattus norvegicus) was conducted at five sites in northern China's farming–pastoral ecotone. Through a cross‐factorial comparison, we aimed to discern whether belonging to the same species or sharing the same capture site predominantly influences the composition of gut microbiota. Notably, the observed variations in microbiome composition among these four rodent species match the host phylogeny at the family level but not at the species level. The gut microbiota of these four rodent species exhibited typical mammalian characteristics, predominantly characterized by the Firmicutes and Bacteroidetes phyla. As the geographic distance between populations increased, the number of shared microbial taxa among conspecific populations decreased. We observed that within a relatively small geographical range, even different species exhibited convergent α‐diversity due to their inhabitation within the same environmental microbial pool. In contrast, the composition and structure of the intestinal microbiota in the allopatric populations of A. agrarius demonstrated marked differences, similar to those of C. barabensis. Additionally, geographical environmental elements exhibited significant correlations with diversity indices. Conversely, host‐related factors had minimal influence on microbial abundance. Our findings indicated that the similarity of the microbial compositions was not determined primarily by the host species, and the location of the sampling explained a greater amount of variation in the microbial composition, indicating that the local environment played a crucial role in shaping the microbial composition. [ABSTRACT FROM AUTHOR]

Long-term deposition of atmospheric pollutants emitted from coal combustion and their effects on the eco-environment have been extensively studied around coal-fired power plants. However, the effects of coal-fired power plants on soil microbial communities have received little attention through atmospheric pollutant deposition and coal-stacking. Here, we collected the samples of power plant soils (PS), coal-stacking soils (CSS) and agricultural soils (AS) around three coal-fired power plants and background control soils (BG) in Huainan, a typical mineral resource-based city in East China, and investigated the microbial diversity and community structures through a high-throughput sequencing technique. Coal-stacking significantly increased (p < 0.05) the contents of total carbon, total nitrogen, total sulfur and Mo in the soils, whereas the deposition of atmospheric pollutants enhanced the levels of V, Cu, Zn and Pb. Proteobacteria, Actinobacteria, Thaumarchaeota, Thermoplasmata, Ascomycota and Basidiomycota were the dominant taxa in all soils. The bacterial community showed significant differences (p < 0.05) among PS, CSS, AS and BG, whereas archaeal and fungal communities showed significant differences (p < 0.01) according to soil samples around three coal-fired power plants. The predominant environmental variables affecting soil bacterial, archaeal and fungal communities were Mo-TN-TS, Cu-V-Mo, and organic matter (OM)-Mo, respectively. Certain soil microbial genera were closely related to multiple key factors associated with stacking coal and heavy metal deposition from power plants. This study provided useful insight into better understanding of the relationships between soil microbial communities and long-term disturbances from coal-fired power plants. [Display omitted] [ABSTRACT FROM AUTHOR]

Nitrogen (N) deposition affects ecosystem functions crucial to human health and well‐being. However, the consequences of this scenario for soil ecosystem multifunctionality (SMF) in forests are poorly understood. Here, we conducted a long‐term field experiment in a temperate forest in China, where N deposition was simulated by adding N above and under the canopies. We discover that canopy N addition promotes SMF expression, whereas understory N addition suppresses it. SMF was regulated by fungal diversity in canopy N addition treatments, which is largely due to the strong resistance to soil acidification and efficient resource utilization characteristics of fungi. While in understory N addition treatments, SMF is regulated by bacterial diversity, which is mainly because of the strong resilience to disturbances and fast turnover of bacteria. Furthermore, rare microbial taxa may play a more important role in the maintenance of the SMF. This study provides the first evidence that N deposition enhanced SMF in temperate forests and enriches the knowledge on enhanced N deposition affecting forest ecosystems. Given the divergent results from two N addition approaches, an innovative perspective of canopy N addition on soil microbial diversity‐multifunctionality relationships is crucial to policy‐making for the conservation of soil microbial diversity and sustainable ecosystem management under enhanced N deposition. In future research, the consideration of canopy N processes is essential for more realistic assessments of the effects of atmospheric N deposition in forests. [ABSTRACT FROM AUTHOR]

The biodiversity–ecosystem function (BEF) relationship is the basis for studying the restoration of degraded ecosystems, and the simultaneous assessment of multi-trophic-level biodiversity and ecosystem multifunctionality relationship is more conducive to unravelling the restoration mechanism of degraded ecosystems, especially for degraded forest ecosystems with harsh habitats and infertile soils such as karst. In this study, we evaluated the biodiversity and soil multifunctionality (SMF) of degraded karst forests (scrub, SB; secondary growth forests, SG; old-growth forests, OG) in the Maolan National Nature Reserve, China, using 30 sample plots. Biodiversity and soil multifunctionality (SMF) at three trophic levels (plant–soil fauna–soil microorganisms), were assessed through vegetation surveys and soil sampling. One-way ANOVA showed that SMF increased with natural restoration, but multi-trophic level biodiversity showed different trends. Pearson's correlation analysis showed a positive correlation between plant species diversity and SMF (p < 0.001), whereas soil fauna and soil microorganisms were negatively correlated with SMF. Structural equation modeling revealed a cascading effect of the multi-trophic level on the stimulation of the SMF during restoration. Only soil microorganisms exhibited a direct driving effect on SMF (p < 0.001), whereas plants indirectly influenced soil microorganisms through soil fauna, which subsequently affected the SMF. Although we observed the negative effects of increased plant diversity on soil fauna and soil microbial diversity in terms of quantitative relationships, the increase in soil fauna species and the evenness of soil microbial function still contributed to SMF restoration. This study revealed the cascading effects of multi-trophic diversity in promoting SMF restoration and emphasized that soil microbes are key to unraveling restoration mechanisms and processes, whereas soil fauna is an important intermediate link. [ABSTRACT FROM AUTHOR]

Long-term plant residue retention can effectively replenish soil quality and fertility. In this study, we collected rhizosphere soil from the residual roots of annual Cenchrus fungigraminus in the Ulan Buh Desert over the past 10 years. The area, depth, and length of these roots decreased over time. The cellulose content of the residual roots was significantly higher in the later 5 years (2018–2022) than the former 5 years (2013–2017), reaching its highest value in 2021. The lignin content of the residual roots did not differ across samples except in 2015 and reached its highest level in 2021. The total sugar of the residual roots in 2022 was 227.88 ± 30.69 mg·g−1, which was significantly higher than that in other years. Compared to the original sandy soil, the soil organic matter and soil microbial biomass carbon (SMBC) contents were 2.17–2.41 times and 31.52–35.58% higher in the later 3 years (2020–2022) and reached the highest values in 2020. The residual roots also significantly enhanced the soil carbon stocks from 2018–2022. Soil dehydrogenase, nitrogenase, and N-acetyl-β-D-glucosidase (S-NAG) were significantly affected from 2019–2022. The rhizosphere soil community richness and diversity of the bacterial and fungal communities significantly decreased with the duration of the residual roots in the sandy soil, and there was a significant difference for 10 years. Streptomyces, Bacillus, and Sphigomonas were the representative bacteria in the residual root rhizosphere soil, while Agaricales and Panaeolus were the enriched fungal genera. The distance-based redundancy analysis and partial least square path model results showed that the duration of residual roots in the sandy soil, S-NAG, and SMBC were the primary environmental characteristics that shaped the microbial community. These insights provide new ideas on how to foster the exploration of the use of annual herbaceous plants for sandy soil improvement in the future. [ABSTRACT FROM AUTHOR]

Background. In a context of long-term highly intensive grazing in grassland ecosystems, a better understanding of how quickly belowground biodiversity responds to grazing is required, especially for soil microbial diversity. Methods. In this study, we conducted a grazing experiment which included the CK (no grazing with a fenced enclosure undisturbed by livestock), light and heavy grazing treatments in a desert steppe in Inner Mongolia, China. Microbial diversity and soil chemical properties (i.e., pH value, organic carbon, inorganic nitrogen (IN, NH+4 -N and NO-3-N), total carbon, nitrogen, phosphorus, and available phosphorus content) both in rhizosphere and non-rhizosphere soils were analyzed to explore the responses of microbial diversity to grazing intensity and the underlying mechanisms. Results. The results showed that heavy grazing only deceased bacterial diversity in the non-rhizosphere soil, but had no any significant effects on fungal diversity regardless of rhizosphere or non-rhizosphere soils. Bacterial diversity in the rhizosphere soil was higher than that of non-rhizosphere soil only in the heavy grazing treatment. Also, heavy grazing significantly increased soil pH value but deceased NH4+-N and available phosphorus in the non-rhizosphere soil. Spearman correlation analysis showed that soil pH value was significantly negatively correlated with the bacterial diversity in the non-rhizosphere soil. Combined, our results suggest that heavy grazing decreased soil bacterial diversity in the non-rhizosphere soil by increasing soil pH value, which may be due to the accumulation of dung and urine from livestock. Our results highlight that soil pH value may be the main factor driving soil microbial diversity in grazing ecosystems, and these results can provide scientific basis for grassland management and ecological restoration in arid and semi-arid area. [ABSTRACT FROM AUTHOR]

Infant botulism in a 4-month-old boy in China who continued to excrete toxins for over a month despite antitoxin therapy was further treated with fecal microbiota transplantation. After treatment, we noted increased gut microbial diversity and altered fecal metabolites, which may help reduce intestinal pH and enhance anti-inflammatory capabilities. [ABSTRACT FROM AUTHOR]

Introduction: Biodiversity maintenance and its underlying mechanisms are central issues of ecology. However, predicting the composition turnovers of microbial communities at multiple spatial scales remains greatly challenging because they are obscured by the inconsistent impacts of climatic and local edaphic conditions on the assembly process. Methods: Based on the Illumina MiSeq 16S/18S rRNA sequencing technology, we investigated soil bacterial and eukaryotic communities in biocrusts with different successional levels at a subcontinental scale of Northern China. Results: Results showed that irrespective of spatial scale, bacterial a diversity increased but eukaryotic diversity decreased with the primary succession, whereas both ß diversities decreased at the subcontinental scale compared with smaller scales, indicating that the biogeographic pattern of soil microorganisms was balanced by successional convergence and distance decay effect. We found that the convergence of bacterial and eukaryotic communities was attributed to the turnovers of generalist and specialist species, respectively. In this process, edaphic and climatic factors showed unique roles in the changes of diversity at local/subcontinental scales. Moreover, the taxonomic diversity tended to be more susceptible to climatic and edaphic conditions, while biotic factors (photosynthesis and pigments) were more important to phylogenetic diversity. Conclusion: Taken together, our study provided comprehensive insights into understanding the pattern of microbial diversity at multiple spatial scales of drylands. [ABSTRACT FROM AUTHOR]

Introduction: Mossy biocrust represents a stable stage in the succession of biological soil crust in arid and semi-arid areas, providing a microhabitat that maintains microbial diversity. However, the impact of mossy biocrust rhizoid soil and different particle sizes within the mossy biocrust layer and sublayer on microbial diversity and soil enzyme activities remains unclear. Methods: This study utilized Illumina MiSeq sequencing and high-throughput fluorometric technique to assess the differences in microbial diversity and soil extracellular enzymes between mossy biocrust rhizoid soil and different particle sizes within the mossy biocrust sifting and sublayer soil. Results: The results revealed that the total organic carbon (TOC), total nitrogen (TN), ammonium (NH4 +) and nitrate (NO3 -) in mossy biocrust rhizoid soil were the highest, with significantly higher TOC, TN, and total phosphorus (TP) in mossy biocrust sifting soil than those in mossy biocrust sublayer soil. Extracellular enzyme activities (EAAs) exhibited different responses to various soil particle sizes in mossy biocrust. Biocrust rhizoid soil (BRS) showed higher C-degrading enzyme activity and lower P-degrading enzyme activity, leading to a significant increase in enzyme C: P and N: P ratios. Mossy biocrust soils were all limited by microbial relative nitrogen while pronounced relative nitrogen limitation and microbial maximum relative carbon limitation in BRS. The diversity and richness of the bacterial community in the 0.2 mm mossy biocrust soil (BSS0.2) were notably lower than those in mossy biocrust sublayer, whereas the diversity and richness of the fungal community in the rhizoid soil were significantly higher than those in mossy biocrust sublayer. The predominant bacterial phyla in mossy biocrust were Actinobacteriota, Protebacteria, Chloroflexi, and Acidobacteriota, whereas in BSS0.2, the predominant bacterial phyla were Actinobacteriota, Protebacteria, and Cyanobacteria. Ascomycota and Basidiomycota were dominant phyla in mossy biocrust. The bacterial and fungal community species composition exhibited significant differences. The mean proportions of Actinobacteriota, Protebacteria, Chloroflexi, Acidobacteriota, Acidobacteria, Cyanobacteria, and Bacteroidota varied significantly between mossy biocrust rhizoid and different particle sizes of mossy biocrust sifting and sublayer soil (p < 0.05). Similarly, significant differences (p < 0.05) were observed in the mean proportions of Ascomycota, Basidiomycota, and Glomeromycota between mossy biocrust rhizoid and different particle sizes within the mossy biocrust sifting and sublayer soil. The complexity and connectivity of bacterial and fungal networks were higher in mossy biocrust rhizoid soil compared with different particle sizes within the mossy biocrust sifting and sublayer soil. Discussion: These results offer valuable insights to enhance our understanding of the involvement of mossy biocrust in the biogeochemical cycle of desert ecosystems. [ABSTRACT FROM AUTHOR]

With the rapid development of the livestock industry, finding new sources of feed has become a critical issue that needs to be addressed urgently. China is one of the top five sunflower producers in the world and generates a massive amount of sunflower stalks annually, yet this resource has not been effectively utilized. Therefore, in order to tap into the potential of sunflower stalks for animal feed, it is essential to explore and develop efficient methods for their utilization. In this study, various proportions of alfalfa and sunflower straw were co-ensiled with the following mixing ratios: 0:10, 2:8, 4:6, 5:5, 6:4, and 8:2, denoted as A0S10, A2S8, A4S6, A5S5, A6S4, and A8S2, respectively. The nutrient composition, fermentation quality, microbial quantity, microbial diversity, and broad-spectrum metabolomics on the 60th day were assessed. The results showed that the treatment groups with more sunflower straw added (A2S8, A4S6) could start fermentation earlier. On the first day of fermentation, Weissella spp.dominated overwhelmingly in these two groups. At the same time, in the early stage of fermentation, the pH in these two groups dropped rapidly, which could effectively reduce the loss of nutrients in the early stage of fermentation. In the later fermentation period, a declining trend in acetic acid levels was observed in A0S10, A2S8, and A4S6, while no butyric acid production was detected in A0S10 and A2S8 throughout the process. In A4S6, butyric acid production was observed only after 30 days of fermentation. From the perspective of metabolites, compared with sunflower ensiling alone, many bioactive substances such as flavonoids, alkaloids, and terpenes are upregulated in mixed ensiling. [ABSTRACT FROM AUTHOR]

Clubroot (Plasmodiophora brassicae) is an important soilborne disease that causes severe damage to cruciferous crops in China. This study aims to compare the differences in chemical properties and microbiomes between healthy and clubroot-diseased soils. To reveal the difference, we measured soil chemical properties and microbial communities by sequencing 18S and 16S rRNA amplicons. The available potassium in the diseased soils was higher than in the healthy soils. The fungal diversity in the healthy soils was significantly higher than in the diseased soils. Ascomycota and Proteobacteria were the most dominant fungal phylum and bacteria phylum in all soil samples, respectively. Plant-beneficial microorganisms, such as Chaetomium and Sphingomonas, were more abundant in the healthy soils than in the diseased soils. Co-occurrence network analysis found that the healthy soil networks were more complex and stable than the diseased soils. The link number, network density, and clustering coefficient of the healthy soil networks were higher than those of the diseased soil networks. Our results indicate that the microbial community diversity and network structure of the clubroot-diseased soils were different from those of the healthy soils. This study is of great significance in exploring the biological control strategies of clubroot disease. [ABSTRACT FROM AUTHOR]

Purpose: Soil erosion and deposition are natural occurrences that can greatly affect the functions of soil. Currently, soil erosion has become an important cause of soil degradation in the northeast China, which severely limits the sustainable development of agriculture. Therefore, understanding the effects of soil erosion and deposition on multiple soil ecosystem functions and soil microbial communities can facilitate a comprehensive assessment of their influence on soil quality and fertility of this region. Materials and methods: This study investigated the effects of soil erosion and deposition on microbial diversity and community in agroecosystems with Mollisols (black soil) at different sites of a slope in northeastern China. The study involves comparison of four slope sites with different erosion intensities and a deposition site. Firstly, a multifunctionality index was generated after determination of a number of soil physicochemical and microbiological parameters. Then, the soil bacteria were determined by 16 s rRNA gene sequencing technology. Finally, the above data were analyzed to investigate the relationship among microbial community characteristics, soil multifunctionality, and soil erosion and deposition. Results and discussion: Erosion reduces while deposition enhances soil multifunctionality and microbial diversity. Soil multifunctionality decreased from 0.52 (TS) to –0.83 (LS) and increased to 0.85 (FS). Erosion and deposition significantly changed the abundance of Desulfobacterota, Geobacteraceae, Methylomirabilota, and others, which may be related to soil physicochemical properties and hydrothermal conditions. Erosion reduced the complexity and stability of the co-occurrence network of bacteria, whose node and robustness respectively decreased from 540 and 0.1936 (TS) to 488 and 0.1881 (LS), and the vulnerability increased from 0.0006 (TS) to 0.0013 (LS). Moreover, the complexity and stability showed positive correlations with soil multifunctionality and microbial diversity. Overall, our results indicated that erosion and deposition can significantly affect soil multifunctionality and microbial diversity, which will further alter soil microbial communities and their functions. Conclusions: Soil degradation caused by soil erosion may be reflected not only by the reduction of soil nutrients and destruction of soil structure, but also by decreases in soil microbial diversity, network complexity, and stability. Soil degradation caused by erosion includes a decline in soil multifunctionality and microbial characteristics, both of which should be taken into account when treating and rehabilitating degraded soils caused by erosion. [ABSTRACT FROM AUTHOR]

Dynamics of plant communities during forest succession have been received great attention in the past decades, yet information about soil microbial communities that are involved in carbon cycling remains limited. Here we investigated soil microbial community composition and carbohydrate degradation potential using metagenomic analysis and examined their influencing factors in three successional subtropical forests in southern China. Results showed that the abundances of soil bacteria and fungi increased (p ≤ 0.05 for both) with forest succession in relation to both soil and litter characteristics, whereas the bacterial diversity did not change (p > 0.05) and the fungal diversity of Shannon-Wiener index even decreased (p ≤ 0.05). The abundances of microbial carbohydrate degradation functional genes of cellulase, hemicellulase, and pectinase also increased with forest succession (p ≤ 0.05 for all). However, the chitinase gene abundance did not change with forest succession (p > 0.05) and the amylase gene abundance decreased firstly in middlesuccession forest and then increased in late-succession forest. Further analysis indicated that changes of functional gene abundance in cellulase, hemicellulase, and pectinase were primarily affected by soil organic carbon, soil total nitrogen, and soil moisture, whereas the variation of amylase gene abundance was well explained by soil phosphorus and litterfall. Overall, we created a metagenome profile of soil microbes in subtropical forest succession and fostered our understanding of microbially-mediated soil carbon cycling. [ABSTRACT FROM AUTHOR]

In recent decades, ecological cyclic cultivation models have attracted increasing attention, primarily because the decomposition of crop residues and litter enhances soil organic matter content, thereby altering the soil microenvironment and regulating the diversity and functions of soil microbial communities. However, the effects of different coffee waste mulching on the diversity of soil microbial communities and their functions are still unclear. Therefore, this study set up four kinds of covering treatments: uncovered coffee waste (C), covered coffee litter (L), covered coffee pericarp (P), and both covered coffee litter and pericarp (PL). The results showed that compared to the control, coffee pericarp mulching significantly increased the soil available potassium (SAK) content by 18.45% and alkali hydrolyzed N (SAN) content by 17.29%. Furthermore, coffee pericarp mulching significantly increased bacterial richness and diversity by 7.75 and 2.79%, respectively, while litter mulching had little effect on bacterial abundance and diversity was smaller. The pericarp mulching significantly increased the abundance of Proteus by 22.35% and the abundance of Chlamydomonas by 80.04%, but significantly decreased the abundance of Cyanobacteria by 68.38%, while the coffee litter mulching significantly increased the abundance of Chlamydomonas by 48.28%, but significantly decreased the abundance of Cyanobacteria by 73.98%. The increase in soil SAK promoted bacterial Anoxygenic_photoautotrophy, Nitrogen_respiration, Nitrate_respiration, Nitrite_respiration, and Denitrification functions. The above results indicate that the increase in available soil potassium and alkali hydrolyzed N content under coffee pericarp cover is the main reason for promoting the diversity and richness of bacterial community and promoting the changes in bacterial community structure and function. The use of coffee pericarps in coffee plantations for ecological recycling helps to improve the diversity of the soil microbial community and maintain the relative stability of the microbial community structure and function, promoting soil health conservation and the sustainable development of related industries. [ABSTRACT FROM AUTHOR]

Ticks are obligate ectoparasites and vectors of a variety of pathogens in humans and animals. Certain tick-borne pathogens (TBPs) have been identified as the cause of zoonoses, posing potentially significant threats to the human health and livestock industries. Fungi are one of the major TBPs that can affect ticks and cause disease in humans. At present, there are few studies on the diversity of fungal microbial communities carried by Ixodes. Therefore, profiling tick-borne fungi will contribute to understanding the tick-fungal interaction. This study evaluated the community profile and differences in the fungal microbiome in Ixodidae collected on parasitic ticks or nonparasitic ticks in Wuwei, Gansu Province, China. The Shannon index, Simpson index, and Richness index were used to evaluate the diversity of mycobiome. Principle coordinates analysis (PCoA) was conducted to determine patterns of diversity in mycobiome. Using correlation analysis to determine the correlation of mycobiome. The results show that the high-throughput sequencing of the internal transcribed spacer gene generated 3,634,943 raw reads and 7,482 amplicon sequence variants. The dominant tick species in this region was Dermacentor nuttalli (Ixodidae). The mycobiome belonged to four classes—Dothideomycetes, Sordariomycetes, Ustilaginomycetes, and Tremellomycetes—and more than 261 genera, the most abundant genera were Cladosporium, Purpureocillium, Aureobasidium, Tranzscheliella, and Sporormiella. Alpha diversity indicated that the abundance and evenness of mycobiome were marginally higher in nonparasitic ticks than in parasitic ticks. PCoA showed that the community structures of parasitic ticks vary from nonparasitic ticks, samples from nonparasitic ticks tended to cluster more closely than those from the parasitic ticks. Correlation analysis indicated that there was a significant positive correlation or negative correlation between the mycobiome. Our results indicate that the mycobiome carried by Dermacentor nuttalli had rich diversity, and there was a significant difference in mycobiome between parasitic ticks and nonparasitic ticks. These findings may conducive to understand the complex interaction between ticks and commensal fungi and provide help for the further exploration of the behavioral characteristics of ticks and formulation of effective biological control measures. [ABSTRACT FROM AUTHOR]

Covering about 30% of the global total land area, desert ecosystems have been influenced by warming and nitrogen deposition. However, it remains unclear how desert ecosystems respond to warming and nitrogen deposition. Therefore, we conducted a greenhouse experiment to examine the impacts of N addition and warming on the plant–soil system of Neotrinia splendens, the dominant plant in the desert ecosystem in Northern China. Our findings revealed that low-N dose (N1) and high-N dose additions (N2) increased the biomass by 22.83% and 54.23%, respectively; meanwhile, moderate warming (T2) and severe warming (T3) decreased the biomass by 39.07% and 45.47%, respectively. N addition did not significantly affect the C:N:P stoichiometry in the plant–soil system. T2 and T3 decreased the leaf N content by 17.50% and 16.20%, respectively, and decreased the leaf P content by 10.61% and 45.29%, respectively. This resulted in the plant C:N ratio, C:P ratio, and N:P ratio increasing with warming. Furthermore, warming or N addition not only decreased soil microbial diversity, but also inhibited microbial genera associated with nutrient cycling, such as that of Tumebacillus spp., Bacillus spp., and Mortierella spp.; it additionally influenced important bacterial functions, such as nitrate reduction and ureolysis. Moreover, warming and N addition induced P limitation in the plant–soil system by inhibiting soil microorganisms, such as Mortierella spp. and Bacillus spp., which are associated with P transformation; this was also brought about by increasing the effects of leaf P content on leaf N:P. In conclusion, our results showed that warming and N addition had significant effects on the C:N:P stoichiometry of the plant–soil system through microbial mediation and led to P limitation in the system, regardless of how they affected biomass. Soil microorganisms could mediate the impacts of environmental changes on the plant–soil system. Our findings may provide valuable insights for adjusting vegetation restoration strategies in desert ecosystems under environmental changes. [ABSTRACT FROM AUTHOR]

Microcystis blooms have a marked effect on microbial taxonomical diversity in eutrophic lakes, but their influence on the composition of microbial functional genes is still unclear. In this study, the free-living microbial functional genes (FMFG) composition was investigated in the period before Microcystis blooms (March) and during Microcystis blooms (July) using a comprehensive functional gene array (GeoChip 5.0). The composition and richness of FMFG in the water column was significantly different between these two periods. The FMFG in March was enriched in the functional categories of nitrogen, sulfur, and phosphorus cycling, whereas the FMFG in July was enriched in carbon cycling, organic remediation, and metal homeostasis. Molecular ecological network analysis further demonstrated fewer functional gene interactions and reduced complexity in July than in March. Module hubs of the March network were mediated by functional genes associated with carbon, nitrogen, sulfur, and phosphorus, whereas those in July by a metal homeostasis functional gene. We also observed stronger deterministic processes in the FMFG assembly in July than in March. Collectively, this study demonstrated that Microcystis blooms induced significant changes in FMFG composition and metabolic potential, and abundance—information, which can support the understanding and management of biogeochemical cycling in eutrophic lake ecosystems. [ABSTRACT FROM AUTHOR]