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Sand flies have expanded their areas of distribution, thereby increasing the risk of pathogen transmission in non-endemic areas. To establish efficient prevention and control strategies for the transmission of vector-borne pathogens, it is important to understand seasonal dynamics of their vectors. In Mexico, there are several areas where the contact between sand flies, hosts and reservoirs favours the transmission of the pathogen. We compared sand fly communities in a forest management area and a conserved area in Noh-Bec, Quintana Roo, Mexico. The analysis included species diversity, activity peaks and molecular detection of pathogens. Sand flies were collected from November to December 2021 and April to May 2022, during 84 night-traps. The conserved area showed higher numbers and greater species heterogeneity of sand flies as compared with the other sites. The ß-diversity analysis revealed that sites disturbed by logging (S1, S2, S3) had greater similarity (90%) in their sand fly species composition than a conserved area (S4) (similarity = 36%). Although none of the specimens were infected with Leishmania, we detected Wolbachia (19.4%) in all four sites, as well as Bartonella (3.25%) only in the disturbed sites. Further studies on the dynamics of sand fly populations and their association with pathogens are necessary.
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Phlebotomus , Psychodidae , Animales , México , Insectos Vectores , BosquesRESUMEN
Plant and microbial diversity are key to determine ecosystem functioning. Despite the well-known role of local-scale α diversity in affecting vegetation biomass, the effects of community heterogeneity (ß diversity) of plants and soil microbes on above- and belowground biomass (AGB and BGB) across contrasting environments still remain unclear. Here, we conducted a dryness-gradient transect survey over 3000 km across grasslands on the Tibetan Plateau. We found that plant ß diversity was more dominant than α diversity in maintaining higher levels of AGB, while soil fungal ß diversity was the key driver in enhancing BGB. However, these positive effects of plant and microbial ß diversity on AGB and BGB were strongly weakened by increasing climatic dryness, mainly because higher soil available phosphorus caused by increasing dryness reduced both plant and soil fungal ß diversities. Overall, these new findings highlight the critical role of above- and belowground ß diversity in sustaining grassland biomass, raising our awareness to the ecological risks of large-scale biotic homogenization under future climate change.
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Ecosistema , Plantas , Biomasa , Pradera , Fósforo , Suelo , Microbiología del SueloRESUMEN
Environmental DNA (eDNA) metabarcoding is becoming a key tool for biodiversity monitoring over large geographical or taxonomic scales and for elusive taxa such as soil organisms. Increasing sample sizes and interest in remote or extreme areas often require the preservation of soil samples and thus deviations from optimal standardized protocols. However, we still ignore the impact of different methods of soil sample preservation on the results of metabarcoding studies and there is no guideline for best practices so far. Here, we assessed the impact of four methods of soil sample preservation that can be conveniently used also in metabarcoding studies targeting remote or difficult to access areas. Tested methods include: preservation at room temperature for 6 hr, preservation at 4°C for 3 days, desiccation immediately after sampling and preservation for 21 days, and desiccation after 6 hr at room temperature and preservation for 21 days. For each preservation method, we benchmarked resulting estimates of taxon diversity and community composition of three different taxonomic groups (bacteria, fungi and eukaryotes) in three different habitats (forest, river bank and grassland) against results obtained under ideal conditions (i.e., extraction of eDNA immediately after sampling). Overall, the different preservation methods only marginally impaired results and only under certain conditions. When rare taxa were considered, we detected small but significant changes in molecular operational taxonomic units (MOTU) richness of bacteria, fungi and eukaryotes across treatments, but MOTU richness was similar across preservation methods if rare taxa were not considered. All the approaches were able to identify differences in community structure among habitats, and the communities retrieved using the different preservation conditions were extremely similar. We propose guidelines on the selection of the optimal soil sample preservation conditions for metabarcoding studies, depending on the practical constraints, costs and ultimate research goals.
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ADN Ambiental , Biodiversidad , Código de Barras del ADN Taxonómico , Monitoreo del Ambiente , Bosques , SueloRESUMEN
Many regions across the globe are shifting to more arid climates. For shallow lakes, decreasing rainfall volume and timing, changing regional wind patterns and increased evaporation rates alter water regimes so that dry periods occur more frequently and for longer. Drier conditions may affect fauna directly and indirectly through altered physicochemical conditions in lakes. Although many studies have predicted negative effects of such changes on aquatic biodiversity, empirical studies demonstrating these effects are rare. Global warming has caused severe climatic drying in southwestern Australia since the 1970s, so we aimed to determine whether lakes in this region showed impacts on lake hydroperiod, water quality, and α, ß and γ diversity of lake invertebrates from 1998 to 2011. Seventeen lakes across a range of salinities were sampled biennially in spring in the Wheatbelt and Great Southern regions of Western Australia. Multivariate analyses were used to identify changes in α, ß and γ diversity and examine patterns in physicochemical data. Salinity and average rainfall partially explained patterns in invertebrate richness and assemblage composition. Climatic drying was associated with significant declines in lake depth, increased frequency of dry periods, and reduced α and γ diversity (γ declined from ~300 to ~100 taxa from 1998 to 2011 in the 17 wetlands). In contrast, ß diversity remained consistently high, because each lake retained a distinct fauna. Mean α diversity per-lake declined both in lakes that dried and lakes that did not dry out, but lakes which retained a greater proportion of their maximum depth retained more α diversity. Accumulated losses in α diversity caused the decline in γ diversity likely through shrinking habitat area, fewer stepping stones for dispersal and loss of specific habitat types. Biodiversity loss is thus likely from lakes in drying regions globally. Management actions will need to sustain water depth in lakes to prevent biodiversity loss.
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Invertebrados , Lagos , Animales , Biodiversidad , Ecosistema , HumedalesRESUMEN
To better understand how ecosystems are changing, a multifaceted approach to measuring biodiversity that considers species richness (SR) and evolutionary history across spatial scales is needed. Here, we compiled 162 datasets for fish, bird and plant assemblages across the globe and measured how taxonomic and phylogenetic diversity changed at different spatial scales (within site α diversity and between sites spatial ß diversity). Biodiversity change is measured from these datasets in three ways: across land use gradients, from species lists, and through sampling of the same locations across two time periods. We found that local SR and phylogenetic α diversity (Faith's PD (phylogenetic diversity)) increased for all taxonomic groups. However, when measured with a metric that is independent of SR (phylogenetic species variation, PSV), phylogenetic α diversity declined for all taxonomic groups. Land use datasets showed declines in SR, Faith's PD and PSV. For all taxonomic groups and data types, spatial taxonomic and phylogenetic ß diversity decreased when measured with Sorensen dissimilarity and phylogenetic Sorensen dissimilarity, respectively, providing strong evidence of global biotic homogenization. The decoupling of α and ß diversity, as well as taxonomic and phylogenetic diversity, highlights the need for a broader perspective on contemporary biodiversity changes. Conservation and environmental policy decisions thus need to consider biodiversity beyond local SR to protect biodiversity and ecosystem services.
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Biodiversidad , Ecosistema , Animales , Evolución Biológica , Aves , Peces , Filogenia , PlantasRESUMEN
Determining the importance of physical and biological drivers in shaping biodiversity in diverse ecosystems remains a global challenge. Advancements have been made towards this end in large marine ecosystems with several studies suggesting environmental forcing as the primary driver. However, both empirical and theoretical studies point to additional drivers of changes in diversity involving trophic interactions and, in particular, predation. Moreover, a more integrated but less common approach to the assessment of biodiversity changes involves analyses of spatial ß diversity, whereas most studies to date assess only changes in species richness (α diversity). Recent research has established that when cod, a dominant generalist predator, was overfished and collapsed in a northwest Atlantic food web, spatial ß diversity increased; that is, the spatial structure of the fish assemblage became increasingly heterogeneous. If cod were to recover, would this situation be reversible, given the inherent complexity and non-linear dynamics that typify such systems? A dramatic increase of cod in an ecologically similar large marine ecosystem may provide an answer. Here we show that spatial ß diversity of fish assemblages in the Barents Sea decreased with increasing cod abundance, while decadal scale changes in temperature did not play a significant role. These findings indicate a reversibility of the fish assemblage structure in response to changing levels of an apex predator and highlight the frequently overlooked importance of trophic interactions in determining large-scale biodiversity patterns. As increased cod abundance was largely driven by changes in fisheries management, our study also shows that management policies and practices, particularly those involving apex predators, can have a strong effect in shaping spatial diversity patterns, and one should not restrict the focus to effects of climate change alone.
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Ecosistema , Cadena Alimentaria , Animales , Biodiversidad , Explotaciones Pesqueras , Conducta PredatoriaRESUMEN
Ecological drift causes species abundances to fluctuate randomly, lowering diversity within communities and increasing differences among otherwise equivalent communities. Despite broad interest in ecological drift, ecologists have little experimental evidence of its consequences in nature, where competitive forces modulate species abundances. We manipulated drift by imposing 40-fold variation in the size of experimentally assembled annual plant communities and holding their edge-to-interior ratios comparable. Drift over three generations was greater than predicted by neutral models, causing high extinction rates and fast divergence in composition among smaller communities. Competitive asymmetries drove populations of most species to small enough sizes that demographic stochasticity could markedly influence dynamics, increasing the importance of drift in communities. The strong effects of drift occurred despite stabilizing niche differences, which cause species to have greater population growth rates when at low local abundance. Overall, the importance of ecological drift appears greater in non-neutral communities than previously recognized, and varies with community size and the type and strength of density dependence.
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Biodiversidad , Ecología , Ecosistema , Plantas/clasificación , Modelos Biológicos , Dinámica PoblacionalRESUMEN
Intensive forest management, together with fire suppression, have decreased structural complexity and altered dynamics of boreal forests profoundly. Such management threatens forest biodiversity and can reduce the provision of ecosystem services. Although the importance of ecosystem services is widely acknowledged, conservation strategies are hindered by poor knowledge about diversity patterns of service provider species as well as on mechanisms affecting these assemblages at different spatial and temporal scales. In this study, we assessed the effect of disturbance management on forest pollinator communities. To do so, we used a large-scale ecological experiment conducted in the year 2000, where forest complexity was manipulated with different harvest regimes and prescribed fire. Results were consistent with a positive response of pollinators to increasing habitat heterogeneity driven by past disturbances. Harvested sites harbored a diverse pollinator community, and showed higher spatial and temporal turnover in species richness. Conversely, old-growth forest communities were a nested subset of harvested sites and contained half of their total diversity. Variation in community composition (ß diversity) was primarily affected by species temporal turnover. Throughout the season, ß diversity was controlled by fire and harvesting legacies, which provide environmental heterogeneity in the form of flowering and nesting resources over space and time. Conservation strategies may undervalue ecosystem services in dynamic, naturally disturbance-driven, landscapes when relying solely on undisturbed forests areas. However, maintaining natural dynamics in early successional forests, by emulating natural disturbances at harvesting, hold promise for the conservation of both biodiversity and ecosystem services in boreal forests.
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Biodiversidad , Incendios , Agricultura Forestal/métodos , Bosques , Polinización , Conservación de los Recursos Naturales , Finlandia , Fenómenos Fisiológicos de las Plantas , TaigaRESUMEN
The vertical distribution of phytoplankton plays a crucial role in shaping the dynamics and structure of aquatic communities. In highly dynamic reservoir systems, water level fluctuations significantly affect the physiochemical conditions and the phytoplankton community. However, the specific effects on the vertical characteristics of phytoplankton between the mainstream and the tributary bay of the reservoir remain unstudied. This study investigated the vertical aspects of phytoplankton density, biomass, α and ß diversity through monthly sampling over two years in the mainstream (Chang Jiang, CJ) and a tributary bay (Xiang Xi, XX) of the Three Gorges Reservoir in China. Phytoplankton density and biomass were significantly higher in XX, indicating an increased risk of algal blooms in the tributary. The phytoplankton community in CJ showed more stable species-environment relationships, a lower Shannon index and a higher evenness index, suggesting a relatively simple structure and a more uniform distribution of phytoplankton among different water layers. Conversely, XX showed greater differences between water layers (higher ß diversity), with significant negative correlations with water level and positive correlations with DO difference, dissolved silica (DSi) difference, and stratification. Peak phytoplankton density and biomass, as well as high ß diversity in XX, occurred during periods of decreased water levels with strong stratification in spring and summer. A structural equation model complemented by path analysis revealed that a decrease in water level could increase ß diversity either directly through internal processes with extended residence time or indirectly by modifying stratification and the vertical distribution of DSi in XX. Therefore, a proposed water quality management strategy for XX was to increase the water level or reduce ß diversity by implementing artificial mixing during stratification periods. Overall, this study lies in its comprehensive investigation of the vertical characteristics of the phytoplankton community in both the mainstream and the tributary bay of the Three Gorges Reservoir, elucidating the significant impact of water level fluctuations and providing insights for targeted water quality management strategies in the tributary bay to mitigate potential ecological impacts.
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Woodpeckers exhibit selectivity when choosing tree cavities for nest development in forest ecosystems, and fungi play a significant and important role in this ecological process. Therefore, there is a complex and intricate relationship between the various behaviors of woodpeckers and the occurrence of fungal species. Research into the complex bond between fungi and woodpeckers was undertaken to provide more information about this remarkable ecological relationship. Through the process of line transect sampling, woodpecker traces were searched for, and mist nets were set up to capture them. A total of 21 woodpeckers belonging to four species were captured. High-throughput sequencing of the ITS region was performed on fungal-conserved samples to enable an in-depth analysis of the fungal communities linked to the woodpeckers' nests. Members of Ascomycota were the most abundant in the samples, accounting for 91.96% of the total, demonstrating the importance of this group in the forest ecosystem of this station. The statistical results indicate significant differences in the fungal diversity carried by woodpeckers among the different groups. Species of Cladosporium were found to be the most prevalent of all the detected fungal genera, accounting for 49.3%. The top 15 most abundant genera were Cladosporium, Trichoderma, Beauveria, Epicococcum, Hypoxylon, Penicillium, Nigrospora, Aspergillus, Oidiodendron, Cercospora, Talaromyces, Phialemo-nium, Petriella, Cordyceps, and Sistotrema. The standard Bray-Curtis statistical technique was used in a hierarchical clustering analysis to compute inter-sample distances, allowing for the identification of patterns and correlations within the dataset. We discovered that in the grouped samples from woodpeckers, there were differences in the diversity of fungal communities carried by four woodpecker species, but the less dominant fungal species were still similar. The findings highlight the need to consider these diverse ecological linkages in woodpecker research and conservation efforts.
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Root-centric studies have revealed fast taxonomic turnover across root neighborhoods, but how such turnover is accompanied by changes in species functions and phylogeny (i.e., ß diversity) remains largely unknown. As ß diversity can reflect the degree of community-wide biotic homogenization, such information is crucial for better inference of below-ground assembly rules, community structuring, and ecosystem processes. We collected 2480 root segments from 625 0-30 cm soil profiles in a subtropical forest in China. Root segments were identified into 138 species with DNA-barcoding with six root morphological and architectural traits measured per species. By using the mean pairwise (Dpw ) and mean nearest neighbor distance (Dnn ) to quantify species ecological differences, we first tested the non-random functional and phylogenetic turnover of root neighborhoods that would lend more support to deterministic over stochastic community assembly processes. Additionally, we examined the distance-decay pattern of ß diversity, and finally partitioned ß diversity into geographical and environmental components to infer their potential drivers of environmental filtering, dispersal limitation, and biotic interactions. We found that functional turnover was often lower than expected given the taxonomic turnover, whereas phylogenetic turnover was often higher than expected. Phylogenetic Dpw (e.g., interfamily species) turnover exhibited a distance-decay pattern, likely reflecting limited dispersal or abiotic filtering that leads to the spatial aggregation of specific plant lineages. Conversely, both functional and phylogenetic Dnn (e.g., intrageneric species) exhibited an inverted distance-decay pattern, likely reflecting strong biotic interactions among spatially and phylogenetically close species leading to phylogenetic and functional divergence. While the spatial distance was generally a better predictor of ß diversity than environmental distance, the joint effect of environmental and spatial distance usually overrode their respective pure effects. These findings suggest that root neighborhood functional homogeneity may somewhat increase forest resilience after disturbance by exhibiting an insurance effect. Likewise, root neighborhood phylogenetic heterogeneity may enhance plant fitness by hindering the transmission of host-specific pathogens through root networks or by promoting interspecific niche complementarity not captured by species functions. Our study highlights the potential role of root-centric ß diversity in mediating community structures and functions largely ignored in previous studies.
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Biodiversidad , Ecosistema , Filogenia , Bosques , Suelo , PlantasRESUMEN
Humic acid (HA) can substantially enhance plant growth and improve soil health. Currently, the impacts of HA concentrations variation on the development and soil quality of Panax notoginseng (Sanqi) from the forest understorey are still unclear. In this study, exogenous HA was administered to the roots of Sanqi at varying concentrations (2, 4, and 6 ml/L). Subsequently, the diversity and community structure of bacteria and fungi were assessed through high-throughput sequencing technology. The investigation further involved analyzing the interplay among the growth of sanqi, soil edaphic factors, and the microbial network stability. Our finding revealed that moderate concentrations (4 ml/L) of HA improved the fresh/dry weight of Sanqi and NO3--N levels. Compared with control, the moderate concentrations of HA had a notable impact on the bacterial and fungal communities compositions. However, there was no significant difference in the α and ß diversity of bacteria and fungi. Moreover, the abundance of beneficial bacteria (Bradyrhizobium) and harmful bacteria (Xanthobacteraceae) increased and decreased at 4 ml/L HA, respectively, while the bacterial and fungal network stability were enhanced. Structural equation model (SEM) revealed that the fresh weight of Sanqi and bacterial and fungal communities were the factors that directly affected the microbial network stability at moderate concentrations of HA. In conclusion, 4 ml/L of HA is beneficial for promoting Sanqi growth and soil quality. Our study provides a reference for increasing the yield of Sanqi and sustainable development of the Sanqi-pine agroforestry system.
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Fertilizantes , Bosques , Hongos , Sustancias Húmicas , Panax notoginseng , Microbiología del Suelo , Panax notoginseng/crecimiento & desarrollo , Sustancias Húmicas/análisis , Fertilizantes/análisis , Hongos/crecimiento & desarrollo , Hongos/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/clasificación , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Suelo/química , Microbiota/efectos de los fármacosRESUMEN
Reservoirs, heavily influenced by artificial management, often harbor phytoplankton assemblages dominated by cyanobacteria or dinoflagellates, triggering significant changes in aquatic ecosystems. However, due to limited sampling frequency and insufficient attention to species composition, the bloom processes and key characteristics of phytoplankton community structure have not been systematically elucidated. During the low-water level period when blooms are most likely to occur (June to September) in a tributary bay of the Three Gorges Reservoir, daily sampling was conducted to investigate phytoplankton community composition, identify significant environmental factors, and evaluate important structure characteristics of phytoplankton community. The results showed that Microcystis aeruginosa maintained a clear dominance for almost a month in stage 1, with low Shannon and evenness but a high dominance index. Phytoplankton total density and biomass decreased drastically in stage 2, but Microcystis aeruginosa still accounted for some proportion. The highest Shannon and evenness but the lowest dominance index occurred in stage 3. Peridiniopsis niei occurred massively in stage 4, but its dominant advantages lasted only one to two days. NH4-N was responsible for the dominance of Microcystis aeruginosa, while TP and PO4-P was responsible for the dominance of Peridiniopsis niei; however, precipitation contributed to their drastic decrease or disappearance to some extent. The TN : TP ratio could be considered as an important indicator to determine whether Microcystis aeruginosa or Peridiniopsis niei dominated the phytoplankton community. Throughout the study period, physiochemical factors explained more variation in phytoplankton data than meteorological and hydrological factors. Pairwise comparisons revealed an increase in average ß diversity with stage progression, with higher ß diversities based on abundance data than those based on presence/absence data. Repl had a greater effect on ß diversity differences based on presence/absence data, whereas RichDiff had a greater effect on ß diversity differences based on species abundance data. Co-occurrence networks for stage 1 showed the most complex structure, followed by stage 4, while the network for stage 3 was relatively sparse, although the overall community division remained compact. This study provides a useful attempt to explore the status and changes in phytoplankton community structure during the bloom process through high-resolution investigation.
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The patterns and mechanisms by which soil bacterial and fungal community ß-diversity respond to vegetation degradation in saline-alkaline soils are currently not clear, and in particular, the role of biotic interactions is relatively unknown. To investigate the assembly of bacterial and fungal communities in topsoil (0-10 cm) in saline-alkaline soils at different stages of vegetation degradation, the ß-Mean Nearest Classification Unit Distance, the ß-Nearest Taxon Index, and the Raup-Crick index were calculated. The relative importance of biotic and environmental factors in controlling ß diversity under deterministic processes was also quantified by using relative importance analyses. The ß diversity of soil bacterial and fungal communities responded differently in different stages of vegetation degradation in saline-alkaline soils, with bacterial ß diversity increasing with increasing vegetation degradation but fungal ß diversity showing few differences. Deterministic processes regulated soil bacterial community assembly, and biotic factors were important in driving changes in ß diversity, whereas both deterministic and stochastic processes were essential in soil fungal community assembly, and environmental factors were important in affecting fungal ß diversity. Furthermore, fungal ß diversity is far more affected by interactions between fungus and bacteria than bacteria. Our study demonstrates the different effects of vegetation degradation on bacterial and fungal communities in saline soils to provide the overall implications for saline soils microorganisms in deteriorating ecosystems.
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Ecosistema , Micobioma , Suelo , Microbiología del Suelo , BacteriasRESUMEN
Anthropogenic disturbances have become one of the primary causes of biodiversity decline in freshwater ecosystems. Beyond the well-documented loss of taxon richness in increasingly impacted ecosystems, our knowledge on how different facets of α and ß diversity respond to human disturbances is still limited. Here, we examined the responses of taxonomic (TD), functional (FD) and phylogenetic (PD) α and ß diversity of macroinvertebrate communities to human impact across 33 floodplain lakes surrounding the Yangtze River. We found that most pairwise correlations between TD and FD/PD were low and non-significant, whereas FD and PD metrics were instead positively and significantly correlated. All facets of α diversity decreased from weakly to strongly impacted lakes owing to the removal of sensitive species harboring unique evolutionary legacies and phenotypes. By contrast, the three facets of ß diversity responded inconsistently to anthropogenic disturbance: while FDß and PDß showed significant impairment in moderately and strongly impacted lakes as a result of spatial homogenization, TDß was lowest in weakly impacted lakes. The multiple facets of diversity also responded differently to the underlying environmental gradients, re-emphasizing that taxonomic, functional and phylogenetic diversities provide complementary information on community dynamics. However, the explanatory power of our machine learning and constrained ordination models was relatively low and suggests that unmeasured environmental features and stochastic processes may strongly contribute to macroinvertebrate communities in floodplain lakes suffering from variable levels of anthropogenic degradation. We finally suggested guidelines for effective conservation and restoration targets aimed at achieving healthier aquatic biotas in a context of increasing human impact across the 'lakescape' surrounding the Yangtze River, the most important being the control of nutrient inputs and increased spatial spillover effects to promote natural metasystem dynamics.
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Efectos Antropogénicos , Ecosistema , Humanos , Ríos , Filogenia , Biodiversidad , LagosRESUMEN
[This corrects the article DOI: 10.3389/fcimb.2022.1022857.].
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Imbalanced intestinal microbiota is associated with diseases, including inflammatory bowel disease and obesity, and diet can alter the structure of the gut microbiota. In this study, the effects of dietary treatments including the potential probiotic Lactiplantibacillus plantarum FBT215 with/without prebiotics on the intestinal microbiota composition of mice were investigated. Lactiplantibacillus plantarum FBT215 administration significantly decreased the Firmicutes/Bacteroidetes ratio and increased the abundance of Muribaculum and Duncaniella. The diversity within and between groups was measured according to α and ß diversity metrics, respectively. The Shannon index of α diversity decreased significantly in all treatment groups except the probiotic group, although this group showed an increase in the Chao1 index. Principal coordinate analysis of ß diversity showed that the groups had different species distributions. Finally, gamma-aminobutyric acid (GABA) concentration increased in groups fed L. plantarum FBT215. These findings improve our understanding of the association between the gut microbiota structure and specific probiotic/prebiotic-containing diets.
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The presence of more species in the community of a sampling site (α diversity) typically increases ecosystem functions via nonrandom processes like resource partitioning. When considering multiple communities, we hypothesize that higher compositional difference (ß diversity) increases overall functions of these communities. Further, we hypothesize that the ß diversity effect is more positive when ß diversity is increased by nonrandom assembly processes. To test these hypotheses, we collected bacterioplankton along a transect of 6 sampling sites in the southern East China Sea in 14 cruises. For any pairs of the 6 sites within a cruise, we calculated the Bray-Curtis index to represent ß diversity and summed bacterial biomass as a proxy to indicate the overall function of the two communities. We then calculated deviation of observed mean pairwise phylogenetic similarities among species in two communities from random to represent the influences of nonrandom processes. The bacterial ß diversity was found to positively affect the summed bacterial biomass; however, the effect varied among cruises. Cross-cruise comparison indicated that the ß diversity effect increased with the nonrandom processes selecting for phylogenetically dissimilar species. This study extends biodiversity-ecosystem functioning research to the scale of multiple sites and enriches the framework by considering community assembly processes. IMPORTANCE The implications of our analyses are twofold. First, we emphasize the importance of studying ß diversity. We expanded the current biodiversity-ecosystem functioning framework from single to multiple sampling sites and investigated the influences of species compositional differences among sites on the overall functioning of these sites. Since natural ecological communities never exist alone, our analyses allow us to more holistically perceive the role of biodiversity in natural ecosystems. Second, we took community assembly processes into account to attain a more mechanistic understanding of the impacts of biodiversity on ecosystem functioning.
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Biodiversidad , Ecosistema , Biomasa , Filogenia , Organismos Acuáticos , Bacterias/genéticaRESUMEN
[This corrects the article DOI: 10.3389/fmicb.2022.1052161.].
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BACKGROUND: Sorghum is a cereal source of energy, carbohydrates, resistant starch, proanthocyanidins, and 3-deoxyanthocyanins; it promotes satiety by slowing digestion and benefits intestinal health. OBJECTIVE: This study investigated the effects of extruded sorghum SC319 consumption on intestinal health, weight loss, and inflammatory markers in men with overweight. METHODS: This was a randomized, controlled, single-blind clinical trial. Twenty-one men were randomly allocated into one of two groups: the sorghum group (test), which received 40 g of extruded SC319 whole sorghum (n = 10), or the wheat group (control), which received 38 g of extruded whole wheat (n = 11) for eight weeks. RESULTS: The sorghum consumption increased the weight loss intragroup, decreased the body fat percentage intergroup, and did not change inflammatory markers, while the wheat group had increased IL-6 levels compared to baseline. Short-chain fatty acid production, fecal pH, and α and ß diversity indexes did not differ intra- and intergroup after interventions. However, sorghum consumption decreased genus levels of Clostridium_sensu_stricto 1, Dorea, and Odoribacter and increased CAG-873 and Turicibacter compared to baseline. Further, sorghum showed a tendency (p = 0.07) to decrease the proteobacteria phyla compared to wheat. CONCLUSION: Extruded sorghum SC319 improved intestinal microbiota and body composition and promoted weight loss, demonstrating its prebiotic potential.