Community Patterns Research Articles

A Study of the Diversity Patterns of Desert Vegetation Communities in an Arid Zone of China.

The Gobi Desert ecosystem is currently experiencing the impacts of persistent climate warming and extreme weather. However, the relative influences of factors such as soil, climate, and spatial variables on the β-diversity of desert plants and their key components have not been systematically studied. In this research, the Dunhuang North Mountain and Mazong Mountain areas were selected as study areas, with a total of 79 plant community plots systematically established. The aim was to explore intercommunity β-diversity and its components and to analyze the interrelationships with climate factors, soil factors, and geographic distance. The results indicate that (1) there is a geographic decay pattern and significant differences among plant communities in the Dunhuang North Mountain and Mazong Mountain areas, with β-diversity primarily driven by replacement components. (2) Climate, soil, and geographic distance significantly influence β-diversity and its replacement components, with climate factors exerting the greatest influence and geographic distance the least. (3) Multiple regression analysis (MRM) reveals differential effects of climate factors, soil factors, and geographic distance on β-diversity and its replacement components, with climate and soil factors exerting a much greater influence than geographic distance. In summary, the β-diversity of plant communities and their replacement components in the Dunhuang North Mountain and Mazong Mountain areas result from the combined effects of habitat filtering and dispersal limitation, with habitat filtering having a greater impact, while environmental heterogeneity is an important factor influencing species differences in this region.

Assembly and co-occurrence pattern of microbial communities in bulk and rhizosphere soils of Pinus elliottii plantations on sandy lands in China

Assembly and co-occurrence pattern of microbial communities in bulk and rhizosphere soils of Pinus elliottii plantations on sandy lands in China

The species diversity and phylogenetic structure patterns of desert plant communities in the Turpan-Hami region, Xinjiang

Desert plant communities play a crucial role in enhancing desert ecosystem productivity and stability but are highly susceptible to environmental changes owing to their limited resilience and resistance to disturbances, making it essential to understand the factors influencing their diversity patterns and community structure, particularly under the threat of climate change and intensifying droughts. This study focused on the Turpan-Hami desert region, a typical desert ecosystem in which diversity patterns and community structures remain unclear. We established 101 sampling sites ranging from elevations of -134 to 2056m and recorded community information, including species composition, height, coverage, and density, using the sample plot method. The diversity patterns were analyzed using regression analysis, and the phylogenetic structure was assessed. Additionally, Canonical Correspondence Analysis, Mantel tests, and General Linear Models were used to identify the key factors affecting community structure. Our results demonstrated that the species richness and phylogenetic diversity of plant communities exhibited a monotonic increase with elevation, and the phylogenetic structure exhibited low clustering and high dispersion along the elevational gradient. The annual mean temperature emerged as the most significant factor influencing diversity patterns, with soil nutrients, such as total potassium and available phosphorus, also affecting the spatial distribution of diversity. Notably, no significant correlations were found between community phylogenetic structure and abiotic factors, highlighting the complex interactions that drive diversity in the Turpan-Hami region. This study offers valuable insights into the mechanisms shaping desert plant community diversity and is essential for biodiversity conservation efforts in fragile desert ecosystems amid climate change.

Parental care reduces parasite-induced mortality in a coral reef fish

Settlement patterns of juvenile fish shape coral reef communities. During the recruitment process, predation rates are extremely high. However, the role that parental care plays in reducing mortality, especially by cryptic natural enemies such as parasites, remains largely unstudied. We investigated whether parental care in the spiny chromis damselfish ( Acanthochromis polyacanthus ) protects juveniles from parasite-induced mortality by gnathiid isopods ( Gnathia aureamaculosa ). Using laboratory experiments, we found that survival of recently hatched juveniles when exposed to gnathiids was higher when parents were present (77%) than when parents were absent (25%). Investigation of their faeces in the field and laboratory indicates that adults consume gnathiids. Together, our data suggest that parental care plays a key role in reducing parasite-induced mortality of juvenile spiny chromis via parental consumption of gnathiids. This highlights the overlooked role of parasites as a source of high mortality in juvenile coral reef fishes and the composition of coral reef fish communities.

Are Wild Prey Sufficient for the Top Predators in the Lowland Protected Areas of Nepal?

A balanced equilibrium between carnivores and their prey is crucial for maintaining ecosystem sustainability. In this study, we applied the predator-prey power law equation to assess the balance between the biomass densities of carnivores and their wild prey within Nepal's lowland protected areas during 2013, 2018, and 2022. The estimated value of the power law exponent k for predator-prey biomass was 0.71 (95% CI = 0.39-1.05), indicating an approximate threefold increase in predator biomass density for every fivefold increase in prey biomass density. Consequently, this creates a systematically bottom-heavy predator-prey biomass pyramid. This finding, consistent with the k = 3/4 trophic biomass scaling across ecosystems, suggests that predator biomass is proportionally sustained by prey biomass, indicating a balance between top predators and their wild prey in Nepal's lowland protected areas. We further demonstrated it is possible to retain the overall power law exponent while jointly measuring intraguild competition between two predators with canonical correlation analysis. This understanding opens avenues for future research directed toward unraveling the factors that drive these consistent growth patterns in ecological communities.

Disclosing the key role of Fe/As/Cu in community co-occurrence and microbial recruitment in metallurgical ruins

Mining activities have led to the persistent presence of substantial heavy metals at metallurgical sites. However, the impact of long-term and complex heavy metal pollution in metallurgical ruins on the structure and spatial shift of microbiome remains unclear. In this study, we focused on various types of metallurgical sites to uncover the occurrence of heavy metals in abandoned mines and the response patterns of microbial communities. The results indicate that mining activities have caused severe exceedances of multiple heavy metals, with AsBio, CuBio, and FeBio being the primary factors affecting community structure and function. Co-occurrence network analyses suggest that several genera, including Ellin6515, Cupriavidus, Acidobacteria genus RB41, Vicinamibacteraceae, Blastococcus, and Sphingomonas, may play significant roles in the synergistic metabolism of communities responding to Fe-Cu-As stress. Although random dispersal contributed to community migration, null models emphasized that variable selection predominates in the spatial turnover of community composition. Additionally, metagenomic prediction (PICRUSt2) identified key genes involved in stress and detoxification strategies of heavy metals. The composite heavy metal stress strengthened the relationship between network structure and the potential function of the community, along with critical ecosystem functions. Our findings demonstrated that microbial interactions were crucial for ecosystem management and the ecological consequences of heavy metal pollution remediation.

Differential spatial responses and assembly mechanisms of soil microbial communities across region-scale Taiga ecosystems

Different soil microbial communities play distinct key roles in regulating forest ecosystem processes and functions. However, the differences in spatial variability and assembly mechanisms of various taiga forest soil microbial taxa remain poorly understood. Here, we assessed the spatial patterns of bacterial and fungal communities, their assembly processes, and the influencing factors in taiga forest ecosystems in Xinjiang, China. A significant distance decay pattern was observed in the similarity of bacterial and fungal communities, with bacterial communities exhibiting a more pronounced pattern than fungal communities. Stochastic and deterministic processes governed together to drive soil bacterial community assembly, whereas stochastic processes dominated fungal community assembly. The coexistence networks revealed that the interactions of bacterial and fungal networks in the four regions are primarily based on interspecies symbiosis, with fungal coexistence networks demonstrating greater stability than bacterial networks. Additionally, the study identified a positive relationship between the modularity of bacterial networks and dispersal limitation. Analysis of environmental factors revealed that soil pH primarily affects the characteristics and assembly mechanisms of bacterial communities, while vegetation conditions primarily affect fungal diversity and composition, with other unconsidered environmental variables influencing the fungal community assembly process. This study emphasized the distinct ways in which bacteria and fungi respond to environmental factors and interspecies interactions. Our results suggested that distinct restoration measures should be implemented for bacteria and fungi in future conservation efforts for forest soil microorganisms.

Biodiversity of a temperate karst landscape-ice cave collapse doline supports high α-diversity of the soil mesofauna.

Caves represent a specific environment with a special microclimate and fauna adapted to it. However, we have still a restricted knowledge on soil fauna communities in an environments with a marked microclimate gradient at the interface between cave and surface habitats. In the present study, we investigated the community patterns of dominant soil microarthropod group, oribatid mites, and their relationship to environmental factors across the microclimate gradient along a transect with seven study sites from cold and wet cave entrance zone to warm and drier deciduous forest. The cold and wet sites showed low oribatid abundances and a high spatial clustering of individuals in comparison to the warm sites. The oribatid mites showed significantly higher abundance and species richness at warm forest sites. Indicator species analysis indicated specific cold-tolerant species that dominated at cold sites of the gradient, but which were absent at the warmest sites. Variance analysis clarified that community composition at sites were significantly driven by environmental factors: temperature, soil moisture, pH and C/N ratio. The study underlines the importance of ice cave entrances as sources of high α-diversity of soil mesofauna and thus the conservation priority of these valuable habitats.

Characteristics of Pinus hwangshanensis Rhizospheric Fungal Community along Huangshan Mountain's Elevation Gradients, China.

Elevation gradients strongly influence the diversity pattern of soil microorganisms. To date, many studies have elucidated the response of soil microbes to changes in elevation gradients. However, the effects of these gradients on the assembly mechanisms and network complexity of rhizospheric microbial communities remain underexplored. To bridge this knowledge gap, this study assessed the response of rhizospheric fungal communities of Pinus hwangshanensis along different elevation gradients in the Huangshan Mountain scenic area with regard to diversity, community composition, and assembly mechanisms using high-throughput amplicon sequencing. The results revealed significant differences in rhizospheric fungal community composition across three elevation gradients. The soil organic matter and pH were the most relevant factors influencing the changes in rhizospheric fungal community composition. The rhizospheric fungal diversity was significantly lower at both low and high elevations compared to the medium elevation. The rhizospheric fungal community assembly showed a more deterministic process at low and high elevations than at the medium elevation, indicating that stronger environmental filtering contributed to reduced fungal diversity at the extremes of the elevation gradient. In addition, rhizospheric pathogens, particularly Dermateaceae, acted as keystone taxa, diminishing the stability of co-occurrence networks at the medium elevation. This study contributes to a more comprehensive understanding of rhizospheric fungal community patterns and their ecological functions along elevation gradients in mountainous regions.

Bacterial Diversity in Sediments from Lianhuan Lake, Northeast China.

Lake microbiota play a crucial role in geochemical cycles, influencing both energy flow and material production. However, the distribution patterns of bacterial communities in lake sediments remain largely unclear. In this study, we used 16S rRNA high-throughput sequencing technology to investigate the bacterial structure and diversity in sediments across different locations (six independent lakes) within Lianhuan Lake and analyzed their relationship with environmental factors. Our findings revealed that both the alpha and beta diversity of sediment bacterial communities varied significantly among the six independent lakes. Furthermore, changes between lakes had a significant impact on the relative abundance of bacterial phyla, such as Pseudomonadota and Chloroflexota. The relative abundance of Pseudomonadota was highest in Habuta Lake and lowest in Xihulu Lake, while Chloroflexota abundance was lowest in Habuta Lake and highest in Tiehala Lake. At the genus level, the relative abundance of Luteitalea was highest in Xihulu Lake compared to the other five lakes, whereas the relative abundances of Clostridium, Thiobacillus, and Ilumatobacter were highest in Habuta Lake. Mantel tests and heatmaps revealed that the relative abundance of Pseudomonadota was significantly negatively correlated with pH, while the abundance of Chloroflexota was significantly positively correlated with total phosphorus and total nitrogen in water, and negatively correlated with electrical conductivity. In conclusion, this study significantly enhances our understanding of bacterial communities in the different lakes within the Lianhuan Lake watershed.

The diversity and biogeography of bacterial communities in lake sediments across different climate zones

Bacteria are diverse and play important roles in biogeochemical cycling of aquatic ecosystems, but the global distribution patterns of bacterial communities in lake sediments across different climate zones are still obscure. Here we integrated the high-throughput sequencing data of 750 sediment samples from published literature to investigate the distribution of bacterial communities in different climate zones and the potential driving mechanisms. The obtained results indicated that the diversity and richness of bacterial community were notably higher in temperate and cold zones than those in other climate zones. In addition, the bacterial community composition varied significantly in different climate zones, which further led to changes in bacterial functional groups. Specifically, the relative abundance of nitrogen cycling functional groups in polar zones was notably higher compared to other climate zones. Regression analysis revealed that climate (mean annual precipitation, MAP; and mean annual temperature, MAT), vegetation, and geography together determined the diversity pattern of sediment bacterial community on a global scale. The results of partial least squares path modeling further demonstrated that climate was the most significant factor affecting the composition and diversity of bacterial communities, and MAP was the most important climate factor affecting the composition of bacteria community (R2 = 0.443, P < 0.001). It is worth noting that a strong positive correlation was observed between the abundance of the dominant bacterial group uncultured_f_Anaerolineaceae and the normalized difference vegetation index (NDVI; P < 0.001), suggesting that vegetation could affect bacterial community diversity by influencing dominant bacterial taxa. This study enhances our understanding of the global diversity patterns and biogeography of sediment bacteria.

Developing a Dietary Questionnaire for Rural Mexican Americans.

Latinos form the largest ethnic population in the United States (18.5%), and the majority are Mexican Americans (61.4%). Many Mexican Americans have unique dietary behaviors, yet few food frequency questionnaires explicitly define Mexican American diets. The objective of this work was to engage with a population of rural Mexican Americans to develop a Mexican American food frequency questionnaire. Because acculturation is linked to dietary intake, we also examined acculturation by diet. We used mixed methods with three phases: (1) a qualitative phase in which a sample of rural Mexican-Americans (N = 15) identified and provided rich data about foods they ate; (2) a developmental phase in which 4day food records were completed sequentially by two new and different samples of Mexican Americans (N = 19); and 3) a preliminary assessment phase where a new sample of Mexican Americans (N = 49) completed the final food frequency questionnaire. The final questionnaire included many traditional Mexican foods and beverages identified by study participants as part of their typical diet. Traditional Mexican foods and beverages were consumed regularly; little variation in diet was seen by level of acculturation. Respondents perceived diets containing commercial sugar-sweetened beverages as unhealthful, but not those with traditional Mexican drinks, which may represent an unappreciated source of added sugar in the diet. Future work includes studies examining dietary patterns in other urban and rural communities with traditional Mexican diets.

The enhanced neutral process with decreasing cell size: a study on phytoplankton metacommunities from the glacier-fed river of Qinghai-Xizang Plateau.

The cell size of phytoplankton is a key life-history trait and key determinant, and phytoplankton of different cell sizes are differentially affected by ecological processes. However, the study of the assembly patterns and drivers of phytoplankton metacommunities with different cell sizes has not been widely carried out. We provide an in-depth analysis of phytoplankton community diversity across three cell sizes in the glacier-fed river, describing how the pattern of phytoplankton communities differs across cell sizes in response to geochemical gradients. The results show that the smaller phytoplankton (picophytoplankton) are relatively more influenced by dispersal-based stochastic processes, whereas larger ones (microphytoplankton and nanophytoplankton) are more structured by selection-based deterministic processes.

Ecological patterns of benthic foraminiferal communities driven by seasonal and spatial environmental gradients in an Arctic fjord

AbstractArctic fjords, being transitional areas between glacier‐covered land and the ocean, are characterized by strong environmental gradients. The seasonal melting of glaciers generates strong turbidity and primary production antagonist gradients, which can affect benthic habitats. Two sampling campaigns were carried out in Kongsfjorden (Svalbard, Arctic Ocean) in May and August 2021 to investigate seasonal changes in benthic foraminifera spatial distribution and ecosystem functioning along a longitudinal transect of 10 km from the Kronebreen tidewater glacier front. Concurrently, organic matter quantity and biochemical composition, sediment grain size, and physical parameters of the water masses were investigated as possible driving factors of benthic ecosystem responses. In a previous study, three statistically determined foraminiferal biozonations (glacier proximal, medial, and distal) were observed on the basis of their species content within the closest 10 km from the glacier front, presenting similar assemblages in both seasons. Our results indicate that foraminiferal distribution at the local scale is mainly driven by physical and geochemical gradients induced by melting waters and sediment discharges from the tidewater glacier occurring during summer. Due to the climate change, the melting season is expected to last longer and increasing global temperature will much probably accelerate the melting processes. Our findings strongly support the use of foraminifera as bioindicators to monitor the effects of ongoing climate change on the benthic ecosystems of Arctic fjords and, accessorily, as proxies for reconstructing glacier front positions in the recent past.

Biological Decline of Alfalfa Is Accompanied by Negative Succession of Rhizosphere Soil Microbial Communities.

The growth and biological decline of alfalfa may be linked to the rhizosphere microbiome. However, plant-microbe interactions in the rhizosphere of alfalfa and associated microbial community variations with stand age remain elusive. This study explored the successional pattern of rhizosphere microbial communities across different aged alfalfa stands and its relationship with alfalfa decline. Rhizosphere soils were collected from 2- and 6-year-old alfalfa stands. Control soils were collected from interspaces between alfalfa plants in the same stands. Soil bacterial and fungal communities were characterized by 16S and ITS rRNA gene sequencing, respectively. Specific microbial taxa colonized the rhizosphere soils, but not the control soils. The rhizosphere-specific taxa mainly included potentially beneficial genera (e.g., Dechloromonas, Verrucomicrobium) in the young stand and harmful genera (e.g., Peziza, Campylocarpon) in the old stand. Alfalfa roots regulated soil microbial communities by selective promotion or inhibition of distinct taxa. The majority of time-enriched taxa were reported as harmful fungi, whose relative abundances were negatively correlated with plant traits. Time-depleted taxa were mostly known as beneficial bacteria, which had relative abundances positively correlated with plant traits. The relative abundances of functional bacterial genes associated with vancomycin biosynthesis, zeatin biosynthesis, and amino acid metabolism trended lower in rhizosphere soils from the old stand. An upward trend was observed for fungal pathogens and wood saprotrophs with increasing stand age. The results suggest that root activity drives the negative succession of rhizosphere microbial communities during alfalfa decline in old stands.

Inter-algal associations and nutrients linked by Scenedesmus and Desmodesmus structure eukaryotic algal communities.

Eutrophication reduces the variability of the community composition of plankton. However, the mechanisms underlying the diversity and restructuring of eukaryotic algal communities remain unknown. This study analysed the diversity and compositional patterns of algal communities in shallow eutrophic lakes. It investigated how these communities were modified by key genera through mediating inter-algal associations under the influence of abiotic factors. Inter-algal associations explained more variance in algal communities than environmental variables, and variation in composition and diversity was primarily derived from Scenedesmus, Desmodesmus and Cryptomonas, rather than nutrients. Scenedesmus and Desmodesmus were positively correlated with the genera of Chlorophyta and formed the hub of the algal association network. When the relative abundance of Scenedesmus and Desmodesmus increased from 0.41% to 13.74%, communities enriched in biomarkers of Bacillariophyta, Chrysophyceae and Cryptophyta transitioned to communities enriched in biomarkers of Chlorophyta. Moreover, negative associations between the Chlorophyta hub genera and other non-Chlorophyta genera increased. High concentrations of total phosphorus altered the composition of algal communities by increasing the abundance of Scenedesmus and Desmodesmus, which in turn had cascading effects through inter-algal associations. Additionally, algal communities with higher abundances of Scenedesmus and Desmodesmus were more susceptible to the effects of total phosphorus. Our study suggested that inter-algal associations, centred on Scenedesmus and Desmodesmus, had a greater influence on algal diversity and community structure than other factors. Nutrient levels were not a direct driver of algal diversity and community structure adjustments, but acted indirectly by enhancing the influence of Scenedesmus and Desmodesmus.

Bleached Coral Supports High Diversity and Heterogeneity of Bacterial Communities: Following the Rule of the ‘Anna Karenina Principle’

Coral-associated bacteria are sensitive to the health status of coral and proven biomarker(s) of the coral bleaching. However, whether coral specificity or health status play a key role when coral-associated bacteria responding to coral bleaching is not known. Therefore, the bacterial communities of five species of healthy and bleached corals, Acropora millepora, Favites abdita, Galaxea fascicularis, Dipsastraea speciosa and Pocillopora damicornis, were collected along the coast of Sanya, South China Sea and targeted for associated bacterial studies. The relative abundance of the dominant class Gammaproteobacteria tended to be higher in healthy corals, while Alphaproteobacteria were more abundant in bleached corals. Dominant genus Achromobacter demonstrated higher relative abundance in healthy corals (0.675) than in bleached corals (0.151). Most of the bleached corals had high α diversity, β dispersion, heterogeneity and complexity of the co-occurrence network of bacterial communities, which support the ‘Anna Karenina Principle (AKP)’ of diverse in threatened objects and conserved in healthy ones. The bacterial communities in the bleached corals were mostly involved in the selection process, and communities in the healthy corals were involved in the undominated process, which is obtained based on the null model test of β nearest-taxon-index (βNTI) and Bray–Curtis-based Raup–Crick (RCBray). This evidence further confirmed the AKP and revealed that the bacterial communities in the bleached corals were driven by deterministic factors. These findings provide valuable insights into the connection between bacterial and coral status, and the application of the AKP in the changing patterns of bacterial communities during coral bleaching.

Assessment of microbial diversity in various saline soils driven by salt content

The Yellow River Delta, as an important reserve land resource area, faces soil salinization problems. Understanding the bacterial community composition in saline soils is an important foundation for control and utilization of saline soils. However, few studies have been conducted on the composition of bacterial communities in soils with different degrees of salinization. Thus, saline soils categorized into low-salinity (LS), medium-salinity (MS), and high-salinity (HS) based on electrical conductivity (EC) were collected. The 16S rRNA high-throughput sequencing analysis was performed to analyze the effects of salinities on soil bacterial community patterns, as well as the relationships between soil bacterial communities and environmental factors. The results showed that Actinobacteriota, Proteobacteria, Chloroflexi, Firmicutes, Acidobacteriota, Gemmatimonadota and Bacteroidota accounted for almost 90 % of all the bacterial community. The linear discriminant analysis effects (LDA > 3.7) showed that 6, 5 and 3 biomarkers were present in LS, MS and HS soils, respectively, which indicated EC was an important factor influencing the saline soil bacterial community patterns. Redundancy analysis further revealed that the primary environmental parameters impacting the bacterial community were pH, EC, nitrate nitrogen, available phosphorus, total phosphorus, and soil organic matter. According to network analysis, the microbial network complexity was increased steadily with increasing of soil salinity. These findings together revealed that bacterial communities could serve as a reliable way to assess and improve the quality of salinized soils.

Supervised machine learning for understanding and predicting the status of bistable eukaryotic plankton community in urbanized rivers

Understanding and predicting the ecological status of urbanized rivers is crucial for their restoration and management. However, the complex and nonlinear nature of ecological responses poses a challenge to the development of predictive models. Here, the study investigated and predicted the status of eukaryotic plankton communities in urbanized rivers by coupling environmental DNA metabarcoding, the alternative stable states theory, and supervised machine learning (SML) models. The results revealed two distinct states of eukaryotic plankton communities under similar environmental conditions: one state was characterized by the enrichment of a diverse phytoplankton population and the high relative abundance of protozoa, whereas the alternative state was characterized by abundant phytoplankton and fungi with an associated risk of algal blooms. Turbidity was identified as a key driver based on the SML model and Mantel test. Potential analysis demonstrated that the response pattern of eukaryotic plankton communities to turbidity was thresholds with hysteresis (Threshold1 = 17 NTU, Threshold2 = 24 NTU). A reduction in turbidity induced a regime shift in the eukaryotic plankton community toward an alternative state associated with a risk of algal blooms. In the prediction of ecological status, both SML models showed excellent performance (R2 > 0.80, RMSE < 0.1, Kappa > 0.70). Additionally, SHapley Additive exPlanations analysis identified turbidity, chlorophyll-a, chemical oxygen demand (COD), ammonia nitrogen and green algae's amplicon sequence variants as crucial features for prediction, with turbidity and COD showing a synergistic effect on ecological status. A framework was further proposed to enhance the understanding and prediction of ecological status in urbanized rivers. The obtained results of this study demonstrated the feasibility of using SML models to predict and explain the ecological status of urbanized rivers with alternative stable states. This provides valuable insights for the application of SML models in the restoration and management of urbanized rivers.

Effects of Altitude on Airborne Bacteria and Potential Pathogenic Bacteria： A Case of Shigatse of Xizang

Airborne microbes are affected by natural environmental factors and have become a global issue due to their potential threat to human health. To explore the effects of altitude on the communities of microbes and potential pathogenic bacteria, we sampled airborne microbes and soils at sites with different altitudes in Shigatse of Xizang. The results showed a significant difference in bacterial communities between air and soil and a decrease in the contribution of soil to airborne bacteria from the sites with a lower altitude to the sites with a higher altitude. The Chao1 indexes of airborne bacteria were significantly higher in the sites with a lower altitude compared to those with a higher altitude, and the bacterial Bray-Curtis distances between sites with a lower altitude were significantly lower than those between sites with a lower altitude and high altitude. These results indicated that altitude would affect the community patterns of airborne bacteria, and the transport of air would decrease the variations in airborne microbial communities between different sites. Proteobacteria, with 84%-91% of average abundance, predominated in the airborne bacterial communities, but different taxa were enriched in sites with different altitudes. For example, the genera of Flavobacterium and Lactobacillus were enriched in sites with a lower altitude and a higher altitude, respectively. A total of 78 potential bacterial pathogens were detected across all samples, and the relative abundance of them in bacterial communities ranged from 2.69% to 38.19%. These findings indicated that altitude would affect the community compositions of airborne bacteria and potential pathogenic bacteria and suggested the potential threat of airborne bacteria to human health. This study provided a scientific basis for better understanding the distributions of airborne microbes and for air quality improvement and disease prevention in China.