Corrigendum: Taxonomic and functional ß-diversity patterns reveal stochastic assembly rules in microbial communities of seagrass beds.

[This corrects the article DOI: 10.3389/fpls.2024.1367773.].

Asymmetric genetic population structures at the range edges of a mangrove whelk.

Many marine species are distributed across incredibly wide geographical ranges spanning thousands of kilometers often due to movement along prevailing ocean currents. However, data are lacking on genetic connectivity among populations of such widespread species within or among ecoregions, possibly due to the lack of appropriate datasets. In this study, we investigated the genetic structure of populations of the mangrove whelk, Terebralia palustris, using mitochondrial cytochrome oxidase subunit I (COI) sequences. Sequences generated for this study from Okinawa, Japan, were compared to samples from the coast of East Africa analyzed in a previous study. Interestingly, despite considerable distance separating them, the African and Japanese populations share major haplotypes and do not show clear genetic differentiation. At lower latitudes, core African populations exhibited higher genetic diversity than either the more southerly African and Japanese populations. Genetic ß-diversity revealed that the northern edge population in Japan has a greater proportion of ßSNE (the nestedness-resultant component), indicating contemporary migration, whereas the southern edge population in Africa is characterized by a predominant ßSIM (the turnover component), suggesting historical demography. A potential cause of this dissimilarity could be due to the strong Kuroshio Current along the Ryukyu Islands, which may promote larval dispersal. These differing patterns suggest that there may be divergent responses to future climate change at the population level at the periphery of the range of T. palustris.

Understanding the response of the Western Mediterranean cephalopods to environment and fishing in a context of alleged winners of change.

Increasing impacts of both fisheries and climate change have resulted in shifts in the structure and functioning of marine communities. One recurrent observation is the rise of cephalopods as fish recede. This is generally attributed to the removal of main predators and competitors by fishing, while mechanistic evidence is still lacking. In addition, climate change may influence cephalopods due to their high environmental sensitivity. We aim to unveil the effects of different anthropogenic and environmental drivers at different scales focusing on the cephalopod community of the Western Mediterranean Sea. We investigate several ecological indicators offering a wide range of information about their ecology, and statistically relating them with environmental, biotic and fisheries drivers. Our results highlight non-linear changes of indicators along with spatial differences in their responses. Overall, the environment drivers have greater effects than biotic and local human impacts with contrasting effects of temperature across the geographic gradient. We conclude that cephalopods may be impacted by climate change in the future while not necessary through positive warming influence, which should make us cautious when referring to them as generalized winners of current changes.

Regional microbial biogeography linked to soil respiration.

The relationships between α-diversity and ecosystem functioning (BEF) have been extensively examined. However, it remains unknown how spatial heterogeneity of microbial community, i.e., microbial ß-diversity within a region, shapes ecosystem functioning. Here, we examined microbial community compositions and soil respiration (Rs) along an elevation gradient of 853-4420 m a.s.l. in the southeastern Tibetan Plateau, which is renowned as one of the world's biodiversity hotspots. There were significant distance-decay relationships for both bacterial and fungal communities. Stochastic processes played a dominant role in shaping bacterial and fungal community compositions, while soil temperature was the most important environmental factor that affected microbial communities. We evaluated BEF relationships based on α-diversity measured by species richness and ß-diversity measured by community dispersions, revealing significantly positive correlations between microbial ß-diversities and Rs. These correlations became stronger with increasing sample size, differing from those between microbial α-diversities and Rs. Using Structural Equation Modeling (SEM), we found that soil temperature, soil moisture, and total nitrogen were the most important edaphic properties in explaining Rs. Meanwhile, stochastic processes (e.g., homogenous dispersal and dispersal limitation) significantly mediated effects between microbial ß-diversities and Rs. Microbial α-diversity poorly explained Rs, directly or indirectly. In a nutshell, we identified a previously unknown BEF relationship between microbial ß-diversity and Rs. By complementing common practices to examine BEF with α-diversity, we demonstrate that a focus on ß-diversity could be leveraged to explain Rs.

Temporal ß-diversity decomposition: Insights into fish biodiversity dynamics in the Moroccan South Atlantic.

Understanding the various aspects of temporal ß-diversity and their relationships can profoundly enhance the knowledge of the intricate dynamics of biodiversity over temporal scales. In this study, we examined extensive data on fish in the Moroccan South Atlantic, to quantify taxonomic and functional temporal ß-diversity over three five-year periods, determine the relative contributions of turnover and nestedness to each facet, and elucidate the relationship between taxonomic and functional temporal ß-diversity including their components using temporal and spatial comparisons. Our findings revealed a complex relationship between taxonomic and functional temporal ß-diversity, with decoupled variation often observed. Furthermore, the predominant component of functional temporal ß-diversity was functional nestedness, while species turnover had a greater impact on taxonomic temporal ß-diversity. A noteworthy observation was the significant fluctuation in the turnover and nestedness components, despite consistent temporal ß-diversity. These insights underscore the pivotal role of temporal ß-diversity decomposition and advocate for the integration of functional aspects in temporal biodiversity research to provide additional key indicators for biodiversity sustainable management.

Vegetation Affects the Responses of Canopy Spider Communities to Elevation Gradients on Changbai Mountain, China.

Forest canopies, an essential part of forest ecosystems, are among the most highly threatened terrestrial habitats. Mountains provide ideal conditions for studying the variation in community structure with elevations. Spiders are one of the most abundant predators of arthropods in terrestrial ecosystems and can have extremely important collective effects on forest ecosystems. How the diversity and composition of canopy spider communities respond to elevation changes in temperate forests remains poorly understood. In this study, we collected canopy spiders from four elevation sites (800 m, 1100 m, 1400 m, and 1700 m) on Changbai Mountain using the fogging method in August 2016. With the methods of ANOVA analysis, transformation-based redundancy analysis, and random forest analysis, we explored the responses of canopy spider communities to elevation. In total, 8826 spiders comprising 81 species were identified and the most abundant families were Thomisidae, Clubionidae, Linyphiidae, and Theridiidae (77.29% of total individuals). Species richness decreased whereas evenness increased with increasing elevation, indicating that elevation has an important impact on community structure. The pattern of absolute abundance was hump shaped with increasing elevation. We found that the community compositions at the three taxonomic levels (species, family, and guild) along the elevation gradient were obviously altered and the variation in community composition was higher at low-elevation sites than at high-elevation sites. There were 19 common species (23.46%) among the four elevations. Regression and RDA results showed that vegetation variables contributed to the variation in the diversity and composition of canopy spiders. Furthermore, the influence of factors would be weakened with the taxonomic level increasing. Therefore, our findings greatly highlight the important role of vegetation in the diversity and composition of canopy spiders and the influence is closely related to the taxonomic level.

Taxonomic and functional ß-diversity patterns reveal stochastic assembly rules in microbial communities of seagrass beds.

Microorganisms are important members of seagrass bed ecosystems and play a crucial role in maintaining the health of seagrasses and the ecological functions of the ecosystem. In this study, we systematically quantified the assembly processes of microbial communities in fragmented seagrass beds and examined their correlation with environmental factors. Concurrently, we explored the relative contributions of species replacement and richness differences to the taxonomic and functional ß-diversity of microbial communities, investigated the potential interrelation between these components, and assessed the explanatory power of environmental factors. The results suggest that stochastic processes dominate community assembly. Taxonomic ß-diversity differences are governed by species replacement, while for functional ß-diversity, the contribution of richness differences slightly outweighs that of replacement processes. A weak but significant correlation (p < 0.05) exists between the two components of ß-diversity in taxonomy and functionality, with almost no observed significant correlation with environmental factors. This implies significant differences in taxonomy, but functional convergence and redundancy within microbial communities. Environmental factors are insufficient to explain the ß-diversity differences. In conclusion, the assembly of microbial communities in fragmented seagrass beds is governed by stochastic processes. The patterns of taxonomic and functional ß-diversity provide new insights and evidence for a better understanding of these stochastic assembly rules. This has important implications for the conservation and management of fragmented seagrass beds.

A Community-Based Framework Integrates Interspecific Interactions into Forest Genetic Conservation.

Forest genetic conservation is typically species-specific and does not integrate interspecific interaction and community structure. It mainly focuses on the theories of population and quantitative genetics. This approach depicts the intraspecific patterns of population genetic structure derived from genetic markers and the genetic differentiation of adaptive quantitative traits in provenance trials. However, it neglects possible interspecific interaction in natural forests and overlooks natural hybridization or subspeciation. We propose that the genetic diversity of a given species in a forest community is shaped by both intraspecific population and interspecific community evolutionary processes, and expand the traditional forest genetic conservation concept under the community ecology framework. We show that a community-specific phylogeny derived from molecular markers would allow us to explore the genetic mechanisms of a tree species interacting with other resident species. It would also facilitate the exploration of a species' ecological role in forest community assembly and the taxonomic relationship of the species with other species specific to its resident forest community. Phylogenetic ß-diversity would assess the similarities and differences of a tree species across communities regarding ecological function, the strength of selection pressure, and the nature and extent of its interaction with other species. Our forest genetic conservation proposal that integrates intraspecific population and interspecific community genetic variations is suitable for conserving a taxonomic species complex and maintaining its evolutionary potential in natural forests. This provides complementary information to conventional population and quantitative genetics-based conservation strategies.

Urbanization drives biotic homogenization of the avian community in China.

Urbanization-driven biotic homogenization has been recorded in various ecosystems on local and global scales; however, it is largely unexplored in developing countries. Empirical studies on different taxa and bioregions show conflicting results (i.e. biotic homogenization vs. biotic differentiation); the extent to which the community composition changes in response to anthropogenic disturbances and the factors governing this process, therefore, require elucidation. Here, we used a compiled database of 760 bird species in China to quantify the multiple-site ß-diversity and fitted distance decay in pairwise ß-diversities between natural and urban assemblages to assess whether urbanization had driven biotic homogenization. We used generalized dissimilarity models (GDM) to elucidate the roles of spatial and environmental factors in avian community dissimilarities before and after urbanization. The multiple-site ß-diversities among urban assemblages were markedly lower than those among natural assemblages, and the distance decays in pairwise similarities in natural assemblages were more rapid. These results were consistent among taxonomic, phylogenetic, and functional aspects, supporting a general biotic homogenization driven by urbanization. The GDM results indicated that geographical distance and temperature were the dominant predictors of avian community dissimilarity. However, the contribution of geographical distance and climatic factors decreased in explaining compositional dissimilarities in urban assemblages. Geographical and environmental distances accounted for much lower variations in compositional dissimilarities in urban than in natural assemblages, implying a potential risk of uncertainty in model predictions under further climate change and anthropogenic disturbances. Our study concludes that taxonomic, phylogenetic, and functional dimensions elucidate urbanization-driven biotic homogenization in China.

Main drivers of dragonflies and damselflies (Insecta; Odonata) metacommunities in streams inside protected areas in the Brazilian Amazon.

The evaluation of environmental and spatial influence in freshwater systems is crucial for the conservation of aquatic diversity. So, we evaluated communities of Odonata in streams inside and outside sustainable use areas in the Brazilian western Amazon. We predicted that these streams would differ regarding habitat integrity and species α and ß diversity. We also predict that environmental and spatial variables will be important for both suborders, but with more substantial effects on Zygoptera species, considering their nature of forest-specialist. The study was conducted in 35 streams, 19 inside and 16 outside sustainable use areas. The streams outside presented high species richness, abundance, and number of exclusive forest-specialist species from Zygoptera and higher scores of habitat integrity. In contrast, one sustainable use area presented the lowest values of these metrics. Besides, we found that environmental and spatial variables were significantly associated to Zygoptera species composition, but not with Anisoptera, which can be explained by their cosmopolitan nature. Our results indicated that an interplay between environmental and spatial processes determines the structure of the metacommunities of Zygoptera. The less effective dispersal rates and narrow ecological tolerance of Zygoptera species make them more influenced by local conditions and dispersal limitation, and more sensible to habitat modifications. We highlight the importance of improving the local management of the sustainable use areas by environmental agencies, mainly on areas that are losing their capacity to maintain the aquatic fauna, and implementation of social policies toward traditional people.

Spatio-temporal structuring and assembly of abundant and rare bacteria in the benthic compartment of a marginally eutrophic lagoon.

The investigations on ecological processes that structure abundant and rare sub-communities are limited from the benthic compartments of tropical brackish lagoons. We examined the spatial and temporal patterns in benthic bacterial communities of a brackish lagoon; Chilika. Abundant and rare bacteria showed differences in niche specialization but exhibited similar distance-decay patterns. Abundant bacteria were mostly habitat generalists due to their broader niche breadth, environmental response thresholds, and greater functional redundancy. In contrast, rare bacteria were mostly habitat specialists due to their narrow niche breadth, lower environmental response thresholds, and functional redundancy. The spatial patterns in abundant bacteria were largely shaped by stochastic processes (88.7 %, mostly dispersal limitation). In contrast, rare bacteria were mostly structured by deterministic processes (56.4 %, mostly heterogeneous selection). These findings provided a quantitative assessment of the different forces namely spatial, environmental, and biotic that together structured bacterial communities in the benthic compartment of a marginally eutrophic lagoon.

Effects of continuous warming on homogeneity of periphytic protozoan fauna in marine ecosystems.

As a powerful biological indicator, multivariate dispersion in a community is widely used to evaluate the biological evaluation of environmental heterogeneity. To investigate the effects of persistent warming on microbial fauna in marine environments, the periphytic protozoan communities were used as test organisms and incubated in five temperature-controlled circulation system at 22 (control), 25, 28, 31 and 34 °C, respectively. The results showed that (1) there was a clear variation in species occurrence, and the α-/γ-diversity measures decreased with the increase of temperatures; (2) the compositional pattern was significantly driven by the persistent warming compared to community pattern from species-abundance data; and (3) both traditional ß-diversity and multivariate dispersion measures on species compositional matrix were significantly correlative with changes in the temperature. Therefore, it is suggested that continuous temperature fluctuations have a greater impact on homogeneity of species composition of protozoan communities than that of their community structure.

Spatial patterns of ß-diversity under cumulative pressures in the Western Mediterranean Sea.

Understanding the spatial dynamics of biodiversity is an essential issue in marine ecology and requires combining information at local and regional scales. ß-diversity is an important measure of biodiversity that informs on the differences in community composition between sites and, thus, in the species turnover in the community structure. In this study, we analysed and predicted the spatial patterns of ß-diversity for fishes, invertebrates and the demersal assemblage along the Iberian Mediterranean coast. We used Bayesian Bootstrap Generalized Dissimilarity Models (BBGDMs) to study the effects of environment and human pressures on the ß-diversity of invertebrate, fishes and the entire demersal assemblage from 1994 to 2015 using different time windows to account for temporal variability. Then, we used these relationships to predict the spatial patterns of ß-diversity in the whole Iberian Mediterranean coast. Our results highlighted that the regional spatial patterns of ß-diversity were best described by bathymetry and a cumulative index of coastal impacts. We identified specific regions with the highest ß-diversity in the study area, which were complementary to hotspots of species richness and presented different degree of overlapping with existent marine protected areas. Overall, our study illustrates that by modelling spatial turnover using ß-diversity we can better understand and predict spatial variation of biodiversity and the effects of particular variables, providing relevant information to end-users and policy makers for designing specific spatial conservation and management strategies.

Microbial functional heterogeneity induced in a petroleum-polluted soil profile.

Microbial taxonomic diversity declines with increasing stress caused by petroleum pollution. However, few studies have tested whether functional diversities vary similarly to taxonomic diversity along the stress gradient. Here, we investigated soil microbial communities in a petrochemically polluted site in China. Total petroleum hydrocarbon (TPH) concentrations were higher in the middle (2-3 m) and deep soil layer (3-5 m) than in the surface soil layer (0-2 m). Accordingly, microbial taxonomic α-diversity was decreased by 44% (p < 0.001) in the middle and deep soil layers, compared to the surface soil layer. In contrast, functional α-diversity decreased by 3% (p < 0.001), showing a much better buffering capacity to environmental stress. Differences in microbial taxonomic and functional ß-diversities were enlarged in the middle and deep soil layers, extending the Anna Karenina Principle (AKP) that a community adapts to stressful environments in its own way. Consistent with the stress gradient hypothesis, we revealed a higher degree of network connectivity among microbial species and genes in the middle and deep soil layers compared to the surface soil layer. Together, we demonstrate that microbial functionality is more tolerant to stress than taxonomy, both of which were amenable to AKP and the stress gradient hypothesis.

Kelp forests collapse reduces understorey seaweed ß-diversity.

BACKGROUND AND AIMS: Kelps are the primary foundation species in temperate subtidal rocky shores worldwide. However, global change is causing their decline with consequences for the organisms that rely on them. An accurate assessment of these consequences may depend on which attributes of the associated community are considered. This study shows that conventional α-diversity approaches may overlook some of these consequences compared to spatially explicit approaches such as with ß-diversity. METHODS: A 1-year seasonal study was conducted to compare the macroalgal understorey between healthy reefs with a Laminaria ochroleuca canopy and degraded reefs where the canopy collapsed years ago due to excessive fish herbivory. At each reef, the understorey seaweed assemblage was recorded in five replicate quadrats to estimate α-diversity (total richness, species density, Shannon index) and ß-diversity (intra- and inter-reef scale). KEY RESULTS: The understorey assemblage exhibited a distinct seasonal dynamic in both healthy and degraded reefs. α-Diversity attributes increased in spring and summer; turf-forming algae were particularly dominant in degraded reefs during summer. ß-Diversity also showed seasonal variability, but mostly due to the changes in degraded reefs. None of the α-diversity estimates differed significantly between healthy and degraded reefs. In contrast, spatial ß-diversity was significantly lower in degraded reefs. CONCLUSIONS: Although the loss of the kelp canopy affected the composition of the macroalgal understorey, none of the conventional indicators of α-diversity detected significant differences between healthy and degraded reefs. In contrast, small-scale spatial ß-diversity decreased significantly as a result of deforestation, suggesting that the loss of kelp canopy may not significantly affect the number of species but still have an effect on their spatial arrangement. Our results suggest that small-scale ß-diversity may be a good proxy for a more comprehensive assessment of the consequences of kelp forest decline.

Species pool, local assembly processes: Disentangling the mechanisms determining bacterial α- and ß-diversity during forest secondary succession.

Across ecology, and particularly within microbial ecology, there is limited understanding how the generation and maintenance of diversity. Although recent work has shown that both local assembly processes and species pools are important in structuring microbial communities, the relative contributions of these mechanisms remain an important question. Moreover, the roles of local assembly processes and species pools are drastically different when explicitly considering the potential for saturation or unsaturation, yet this issue is rarely addressed. Thus, we established a conceptual model that incorporated saturation theory into the microbiological domain to advance the understanding of mechanisms controlling soil bacterial diversity during forest secondary succession. Conceptual model hypotheses were tested by coupling soil bacterial diversity, local assembly processes and species pools using six different forest successional chronosequences distributed across multiple climate zones. Consistent with the unsaturated case proposed in our conceptual framework, we found that species pool consistently affected α-diversity, even while local assembly processes on local richness operate. In contrast, the effects of species pool on ß-diversity disappeared once local assembly processes were taken into account, and changes in environmental conditions during secondary succession led to shifts in ß-diversity through mediation of the strength of heterogeneous selection. Overall, this study represents one of the first to demonstrate that most local bacterial communities might be unsaturated, where the effect of species pool on α-diversity is robust to the consideration of multiple environmental influences, but ß-diversity is constrained by environmental selection.

Effects of Multiple Environmental Stressors on Zoobenthos Communities in Shallow Lakes: Evidence from a Mesocosm Experiment.

Multiple stressors, including climate change, eutrophication, and pesticide contamination, are significant drivers of the decline in lake zoobenthos. Zoobenthos play a crucial role in aquatic ecosystems, impacting energy dynamics, nutrient cycling, and sediment degradation. However, these stressors have led to a decrease in the abundance and diversity of zoobenthos, resulting in notable changes in species composition and structure. Eutrophication typically increases zoobenthos abundance while reducing taxonomic diversity. Climate change, such as warming and heatwaves, also affects the zoobenthos community structure, with different species exhibiting varying levels of adaptability to temperature changes. Additionally, pesticides like imidacloprid have negative effects on the survival and growth of zoobenthos. However, the interactions between imidacloprid and other stressors remain understudied. Here, we used 48 mesocosms (2500 L) to simulate shallow lakes. We combined nutrient loading, sustained warming, and the imidacloprid pesticide to test how these stressors interactively influence the survival and community of zoobenthos. The experimental results demonstrate that elevated temperatures have a significant impact on aquatic benthic organisms under different treatment conditions. The increase in temperature led to a notable rise in species richness and α-diversity, primarily attributed to the stimulation of metabolic activities in zoobenthos, promoting their growth and reproduction. This finding underscores the potential influence of climate change on aquatic benthic ecosystems, particularly in terms of its promoting effect on α-diversity. However, it is essential to note that elevated temperatures also reduced ß-diversity among different sites, implying a potential trend toward homogenization in zoobenthos communities under warmer conditions. Moreover, this study revealed the interactive effects of multiple stressors on the diversity of aquatic benthic communities. Specifically, the pesticide imidacloprid's impact on zoobenthos is not isolated but demonstrates complex effects within various treatment interactions. In the presence of both temperature elevation and the addition of imidacloprid, the presence of imidacloprid appears to counteract the adverse effects of temperature elevation, resulting in increased species diversity. However, when imidacloprid coincides with nutrient input, it significantly affects α-diversity negatively. These findings highlight the complexity of zoobenthos responses to multiple stressors and how these factors influence both α-diversity and ß-diversity. They provide valuable insights for further research on the conservation and management of ecosystems.

How Biodiversity, Climate and Landscape Drive Functional Redundancy of British Butterflies.

Biodiversity promotes the functioning of ecosystems, and functional redundancy safeguards this functioning against environmental changes. However, what drives functional redundancy remains unclear. We analyzed taxonomic diversity, functional diversity (richness and ß-diversity) and functional redundancy patterns of British butterflies. We explored the effect of temperature and landscape-related variables on richness and redundancy using generalized additive models, and on ß-diversity using generalized dissimilarity models. The species richness-functional richness relationship was saturating, indicating functional redundancy in species-rich communities. Assemblages did not deviate from random expectations regarding functional richness. Temperature exerted a significant effect on all diversity aspects and on redundancy, with the latter relationship being unimodal. Landscape-related variables played a role in driving observed patterns. Although taxonomic and functional ß-diversity were highly congruent, the model of taxonomic ß-diversity explained more deviance than the model of functional ß-diversity did. Species-rich butterfly assemblages exhibited functional redundancy. Climate- and landscape-related variables emerged as significant drivers of diversity and redundancy. Τaxonomic ß-diversity was more strongly associated with the environmental gradient, while functional ß-diversity was driven more strongly by stochasticity. Temperature promoted species richness and ß-diversity, but warmer areas exhibited lower levels of functional redundancy. This might be related to the land uses prevailing in warmer areas (e.g., agricultural intensification).

Microbiome analysis of circulating bacterial extracellular vesicles in obsessive-compulsive disorder.

AIM: The present study examined the microbiome abundance and composition of drug-naive or drug-free patients with obsessive-compulsive disorder (OCD) compared with healthy controls. In addition, in the OCD group, the microbiome composition was compared between early-onset and late-onset OCD. METHODS: Serum samples were collected from 89 patients with OCD and 107 age- and sex-matched healthy controls. Bacterial DNA was isolated from bacteria-derived extracellular vesicles in serum and then amplified and quantified using primers specific to the V3-V4 hypervariable region of the 16S ribosomal RNA gene. The 16S ribosomal DNA gene amplicon sequencing was performed. RESULTS: The pooled estimate showed that α-diversity was significantly reduced in patients with OCD compared with that in healthy controls (PShannon = 0.00015). In addition, a statistically significant difference was observed in ß-diversity between patients with OCD and healthy controls at the order (P = 0.012), family (P = 0.003), genus (P < 0.001), and species (P = 0.005) levels. In the microbiome composition, Pseudomonas, Caulobacteraceae (f), Streptococcus, Novosphingobium, and Enhydrobacter at the genus level were significantly less prevalent in patients with OCD than in controls. In addition, among patients with OCD, the microbial composition in the early-onset versus late-onset types was significantly different with respect to the genera Corynebacterium and Pelomonas. CONCLUSION: The present study showed an aberrant microbiome in patients with OCD, suggesting a role of the microbiota-brain interaction in the pathophysiology of OCD. Further longitudinal studies with larger sample sizes adjusting for various confounders are warranted.

Bacterial Flora on Mist Outlet Surfaces in 4D Theaters and Suspended Particle Concentration Characteristics during 4D Movie Screenings.

In this study, we measured suspended particle concentrations during the screening of 4D movies (3 screens and 15 movies) and 2D movies (9 screens and 9 movies) in 3 movie theaters to obtain a more detailed understanding of the situation of suspended particle concentrations and adherent bacterial flora in 4D movie theaters, which have been introduced in increasing numbers in recent years. The adherent bacterial flora on the floor and mist outlet surfaces in the 4D movie theaters were collected and analyzed. During the movie showings, the concentrations of suspended particles in 4D movie theaters were significantly higher than those in 2D movie theaters (p < 0.001). A significant increase in suspended particle concentrations due to 4D movie effects was also observed. The results of the α-diversity and ß-diversity analyses indicate that the bacterial flora on the surfaces of mist outlets in 4D movie theaters are similar. Moreover, there are many closely related species, and the bacterial flora are rich and contain rare bacterial species. Many of the bacterial genera that are dominant in 4D theaters are suited to aqueous environments, and bacteria in the water supply system may have an impact on the indoor environment.