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Phyto‐ecological studies are crucial in developing insights into community structure and functioning. Here, we studied the phytosociological and soil parameters of Swertia thomsonii – an endemic medicinal plant of western Himalaya. Thirty quadrats were laid out across three different habitats of S. thomsonii in Kashmir Himalaya. Soil samples were collected from each site and soil properties were determined by using standard methods. A total of 62 species belonging to 51 genera and 34 families were recorded across the three study sites. Herbs were dominant (83.87%) followed by shrubs (9.67%), trees (4.83%), and ferns (1.61%). Based on importance value index (IVI) values Cynodon dactylon (42.84), Gaultheria trichophylla (42.44) Leucanthemum vulgare (39.93), Poa angustifolia (30.33), Trifolium pratense (26.67), Galium aparine (25.88), and Androsace rotundifolia (25.82) were found to be dominant species within S. thomsonii assemblages. The maximum (23.14) IVI value of S. thomsonii was recorded at the Doodhpathri site followed by Gulmarg (22.12) and Pahalgam (16.34). Diversity indices varied across three study sites. Plant species richness was recorded maximum at Pahalgam (30 species) followed by Doodhpathri (26 species) and Gulmarg (20 species). Also, Shannon index was recorded maximum (H = 3.03) at the Pahalgam site followed by Doodhpathri (H = 2.99) and Gulmarg (H = 2.62). Simpson index and species evenness were recorded maximum (0.93 and 0.79 respectively) at the Doodhpathri site followed pahalgam (0.92 and 0.67 respectively) and Gulmarg site (0.90 and 0.65 respectively). Soil parameters also varied significantly across study sites. Nitrogen and phosphorous were recorded maximum (465.32 ± 4.26 kg ha−1 and 80.2 ± 3.63 kg ha−1 respectively) at the Gulmarg site and minimum (301.33 ± 2.62 kg ha−1 and 33.63 ± 4.22 kg ha−1 respectively) at Pahalgam site. Potassium was recorded maximum (295.5 ± 3.34 kg ha−1) at the Pahalgam site and minimum (165.83 ± 4.25 kg ha−1) at the Gulmarg site. The scientific information generated could contribute to better management practices for target species and thereby ensuring ecosystem health and sustenance of ecosystem services. [ABSTRACT FROM AUTHOR]

AbstractDamqiong Co Lake (DCL) is a high-altitude (4,450 m) soda lake with high salinity (122.45 ± 6.20 g/L) and carbonate concentrations ((10 ± 0.21 g/L of CO32- and 8.77 ± 0.07 g/L of HCO3-) in the Qinghai-Tibet Plateau (QTP). High-throughput sequencing of 16S rRNA genes was used to examine bacterial and archaeal community compositions in the DCL. The result showed that bacterial diversity (Shannon index values of 4.18 ± 0.42) in DCL were significantly higher (P = 0.012) than Archaeal (2.27 ± 1.01). Bacterial communities comprised by 25 phyla, 40 classes, and 205 genera. The dominant bacterial phyla were the Firmicutes (11.23%–70.05%), Proteobacteria (15.47%–45.27%), Bacteroidetes (9.87%–27.88%) and Actinobacteria (0.98%–11.55%). The dominant bacterial genera were Gracilimonas (1.25%–18.95%), Halomonas (3.99%–15.02%), Nitriliruptor (0.76%–11.30%), Bradymonas (0.08%–6.66%), and Brumimicrobium (0.04%–6.47%). Archaeal communities comprised by 5 phyla, 4 classes, and 26 genera. The dominant archaeal phyla were Euryarchaeota (3.69%–97.12%) and Woesearchaeota (2.85%–92.26%), while the dominant genera were Methanomassiliicoccus (0.36%–76.88%), Woesearchaeota AR16 (2.18%–48.61%), Methanolobus (0.32%–19.87%), and Woesearchaeota AR15 (0.27%–18.20%). Correlation heatmap indicated that the diversity in DCL was highly correlated with pH, CO32-, Cl-, Na+, Mg2+, and temperature (P < 0.001). The unique dominant genera of Bacteria (Bradymonas) and Archaea (Methanomassiliicoccus) in DCL suggests that valuable microbial resources may exist in high-altitude soda lakes like the DCL. [ABSTRACT FROM AUTHOR]

Productive grasslands in temperate regions have relied strongly on low plant diversity with high management intensity and fertiliser inputs. Increasing plant diversity can provide high yields of digestible forage for livestock production with lower environmental impacts, and thus represents a diversity‐dependent nature‐based solution that can deliver multiple ecosystem functions.Sharing lessons from the design of managed, productive grassland communities, we address the following questions: how can we identify combinations of plant species that best deliver a selected function or multiple functions? and; when is community composition more important than species richness?We describe approaches that separate plant diversity into its underlying components: species richness, composition and relative abundance. Disentangling these three components facilitates a more nuanced understanding of how diversity can contribute to the design of diversity‐dependent nature‐based solutions. [ABSTRACT FROM AUTHOR]

Aim: Ocean warming and marine heatwaves are rapidly reconfiguring the composition of seaweed forests—the world's largest coastal vegetated biome. Seaweed forest responses to climate change in remote locations, which constitute the majority of the forest biome, remain however poorly quantified. Here, we examine the temporal stability of the seaweed forests across a global seaweed biodiversity hotspot where several species are predicted to undergo severe range contractions in this century. Location: Western south coast of Australia. Methods: Seaweed forest canopies were censused at 18 shallow (< 10 m) sheltered reefs between 1997 and 2006 and again between 2021 and 2024 (six sites per location). We also surveyed 24 sites to examine whether temporal changes differed over gradients of wave exposure and depth. Results: Seaweed forest canopies across all locations showed surprisingly little change in biomass, cover, stand density and species composition over two decades, with strong spatial structuring across depth and exposure gradients persisting over time. The average thermal affinity of forest canopies (i.e., the community temperature index, CTI) did not track warming, suggesting that factors other than temperature (e.g., wave exposure and depth) are more important drivers of forest stand structure and/or that key thermal thresholds have not yet been crossed. Forests in the location with the most pronounced warming exhibited increased thermal bias over time (total bias of 0.8°C–2.2°C), indicating they were dominated by species with cooler affinities than their local temperatures. Main Conclusions: The greater thermal bias in forests at the warmer edge of southern Australia suggests these will be more susceptible to future warming‐related compositional changes than forests in cooler locations. The relative stability we found contrasts with a current context of rapidly changing seaweed forests nationally and globally, highlighting the need to deepen our ecological understanding of the region so that future changes to its unique biodiversity and ecosystem services can be predicted and mitigated. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Water quality and aquatic ecosystems along lakeshores are vital for ecological balance and human well-being. However, research has primarily focused on plankton, with benthic niches being largely overlooked. To enhance understanding of benthic microbial communities, we utilized 16S and 18S rRNA sequencing alongside multivariate statistical methods to analyze samples from the shoreline of Lake Taihu in Huzhou City, Zhejiang Province. Our results reveal a marked difference in species composition between benthic and planktonic microorganisms, with benthic cyanobacteria predominantly comprising filamentous genera like Tychonema, while 95% of planktonic cyanobacteria were Cyanobium. The β-diversity of benthic microorganisms was notably higher than that of planktonic counterparts. The neutral community model indicated that stochastic processes dominated planktonic microbial assembly, while deterministic processes prevailed in benthic communities. Null models showed that homogeneous selection influenced benthic community assembly, whereas planktonic communities were affected by undominated processes and dispersal limitation. Network analysis indicated that planktonic networks were more stable than benthic networks. Importantly, dominant benthic cyanobacterial genera posed potential toxin risks, highlighting the need for enhanced monitoring and ecological risk assessment. Overall, these findings enhance our understanding of benthic and planktonic microbial communities in lakeshores and offer valuable insights for aquatic assessment and management in eutrophicated environments. [ABSTRACT FROM AUTHOR]

Diet is a major determinant of gut microbiome composition, and variation in diet-microbiome interactions may contribute to variation in their health consequences. To mechanistically understand these relationships, here we map interactions between ∼150 small-molecule dietary xenobiotics and the gut microbiome, including the impacts of these compounds on community composition, the metabolic activities of human gut microbes on dietary xenobiotics, and interindividual variation in these traits. Microbial metabolism can toxify and detoxify these compounds, producing emergent interactions that explain community-specific remodeling by dietary xenobiotics. We identify the gene and enzyme responsible for detoxification of one such dietary xenobiotic, resveratrol, and demonstrate that this enzyme contributes to interindividual variation in community remodeling by resveratrol. Together, these results systematically map interactions between dietary xenobiotics and the gut microbiome and connect toxification and detoxification to interpersonal differences in microbiome response to diet. [Display omitted] • Mapping interactions between the microbiome and ∼150 dietary xenobiotics • Microbial metabolism can convert some compounds into antibiotics and detoxify others • Identification of enzymes that determine community remodeling by dietary xenobiotics Individuals can exhibit significant interpersonal variation in diet-microbiome interaction. This report uncovers how gut microbes can convert some dietary compounds into antibiotics and detoxify others, highlighting mechanisms that explain why the same dietary compound can have different effects on the microbiomes of different individuals. [ABSTRACT FROM AUTHOR]

ABSTRACT Variation in species composition along an environmental gradient (β‐diversity) can inform our understanding of biodiversity patterns and species composition. Beta diversity can be partitioned into species contributions to beta diversity (SCBD) and local contributions to beta diversity (LCBD). While SCBD describes the variations in species composition among samples, LCBD measures the uniqueness of a biological community within a larger ecosystem. Recently developed metrics enabled the estimation of species contribution to total beta diversity (SCBD) and the contribution of individual sites to total beta diversity (LCBD). Utilising these metrics, a one‐time survey of 275 sampling points within four sub‐basins of the Upper Paraná River Hydrographic Basin (low‐flow streams, < 5 m3/s) was conducted to assess fish community composition. Our results show that limnological influences at different scales contribute to higher LCBD. However, land use and species richness were not directly linked to this outcome, suggesting that sites with fewer fish species along sub‐basins contributed to higher beta diversity. It was concluded that beta diversity is more influenced by limnological characteristics and the position of sampling sites along the longitudinal gradient than that based on variations in species composition (SCBD). Moreover, high LCBD values were even found in portions of the gradient with lower species richness. This means that small streams in the sub‐basins of the upper Paraná River are unique and are comprised of varied habitats that contribute to increasing diversity. As such, they should be seen as a target in the development of environmental policies designed to conserve their pristine condition. [ABSTRACT FROM AUTHOR]

One of the most reliable features of natural systems is that they change through time. Theory predicts that temporally fluctuating conditions shape community composition, species distribution patterns, and life history variation, yet features of temporal variability are rarely incorporated into studies of species–environment associations. In this study, we evaluated how two components of temporal environmental variation—variability and predictability—impact plant community composition and species distribution patterns in the alpine tundra of the Southern Rocky Mountains in Colorado (USA). Using the Sensor Network Array at the Niwot Ridge Long‐Term Ecological Research site, we used in situ, high‐resolution temporal measurements of soil moisture and temperature from 13 locations (“nodes”) distributed throughout an alpine catchment to characterize the annual mean, variability, and predictability in these variables in each of four consecutive years. We combined these data with annual vegetation surveys at each node to evaluate whether variability over short (within‐day) and seasonal (2‐ to 4‐month) timescales could predict patterns in plant community composition, species distributions, and species abundances better than models that considered average annual conditions alone. We found that metrics for variability and predictability in soil moisture and soil temperature, at both daily and seasonal timescales, improved our ability to explain spatial variation in alpine plant community composition. Daily variability in soil moisture and temperature, along with seasonal predictability in soil moisture, was particularly important in predicting community composition and species occurrences. These results indicate that the magnitude and patterns of fluctuations in soil moisture and temperature are important predictors of community composition and plant distribution patterns in alpine plant communities. More broadly, these results highlight that components of temporal change provide important niche axes that can partition species with different growth and life history strategies along environmental gradients in heterogeneous landscapes. [ABSTRACT FROM AUTHOR]

In agricultural landscapes, the removal of semi‐natural habitats (SNH) and the intensive use of pesticides contribute to declines of biodiversity, including crop pollinators such as bees (Hymenoptera: Apoidea). However, effects of pesticide use and landscape characteristics on bees have rarely been studied together. In this study, we investigated how SNH in the surrounding landscape, organic and conventional management, and the reduction of fungicides affect wild bee diversity in 32 vineyards in southwest Germany. We used yellow pan traps to sample bees in a crossed design of management (organic vs. conventional) and fungicide use (reduced in fungus‐resistant grape varieties vs. regular) along a gradient with increasing proportions of SNH in the surrounding landscape. Higher proportions of SNH influenced species composition of bees and increased the abundance and richness of above‐ground‐nesting species. Organic vineyards had a 49% higher abundance of bees compared to conventional vineyards. The reduction of fungicides did not affect bee diversity nor abundance. The absence of a response to fungicide intensity suggests that the benefit of organically managed vineyards to wild bees was through differences in their vegetation management, which is in line with the positive response of bees to SNH in the surrounding landscape. Synthesis and applications: Our study underlines that the local provision of diverse vegetation in vineyards and the landscape‐scale provision of suitable SNH are key factors for wild bee conservation in viticulture. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Temperature and precipitation are the main factors determining plant community succession and aboveground net primary productivity (ANPP) in natural grasslands. However, most climate manipulative experiments have mainly focused on their impacts in isolation, especially in alpine regions. Here we explored the relative effects and interaction of warming and precipitation alteration on succession and ANPP using a 7-year experiment involving warming with precipitation alteration (increase (IP) or decrease (DP) in precipitation relative to ambient precipitation (AP)) on the Tibetan Plateau. Our results showed that warming and warm-wet conditions increased species richness, diversity index, height and cover of overall species. Conversely, decreasing precipitation reduced them, but increased S. purpurea and the rate of change in community composition. Importantly, warming mitigated the impacts of decreased precipitation on plant community composition, and the interactive effects of warming and altered precipitation on cover, height and plant ANPP varied with year and plant species. Generally, warming increased community ANPP through increases in forb ANPP or non-dominant species ANPP and biodiversity regardless of change in precipitation. However, decreased precipitation reduced community ANPP via decreases in the ANPP of sedges and forbs and biodiversity. Precipitation alteration affected the relationship between biodiversity and community ANPP regardless of warming (IP

Estuarine phytoplankton communities are acclimated to environmental parameters that change seasonally. With climate change, they are having to respond to extreme weather events that create dramatic alterations to ecosystem function(s) on the scale of days. Herein, we examined the short term (<1 month) shifts in phytoplankton communities associated with four pulse disturbances (Tax Day Flood in 2016, Hurricane Harvey in 2017, Tropical Storm Imelda in 2019, and Winter Storm Uri in 2021) that occurred in Galveston Bay (TX, USA). Water samples collected daily were processed using an Imaging FlowCytobot (IFCB), along with concurrent measurements of temperature, salinity, and chlorophyll-a. Stronger storm events with localized heavy precipitation and flooding had greater impacts on community composition, increasing diversity (Shannon–Weiner and Simpson Indices) while a cold wave event lowered it. Diatoms and dinoflagellates accounted for the largest fraction of the community, cyanobacteria and chlorophytes varied mostly with salinity, while euglenoids, cryptophytes, and raphidophytes, albeit at lower densities, fluctuated greatly. The unconstrained variance of the redundancy analysis models pointed to additional environmental processes than those measured being responsible for the changes observed. These findings provide insights into the impact of pulse disturbances of different magnitudes, durations, and timings on phytoplankton communities. [ABSTRACT FROM AUTHOR]

Temperate woodland vegetation is initially determined by spatiotemporal and historical factors, mediated by complex biotic interactions. However, catastrophic events such as disease outbreaks (e.g., sweet chestnut blight, ash dieback), infestations of insect pests, and human-accelerated climate change can create canopy gaps due to systematic decline in, or loss of, tree species that was once an important part of the canopy. Resultant cascade effects have the potential to alter the composition of woodland ecosystems quickly and radically, but inherent lag times make primary research into these effects challenging. Here, we explore change in woodland vegetation at 10 sites in response to canopy opening using the Elm Decline, a rapid loss of Ulmus in woodlands across northwestern Europe ~ 5800 years ago that coexisted alongside other stressors such as increasing human activity, as a palaeoecological analogue. For arboreal taxa, community evenness significantly decreased, within-site turnover significantly increased, and richness remained unchanged. Changes in arboreal taxa were highly site-specific but there was a substantial decline in woody climbing taxa, especially Hedera (ivy), across the majority of sites. For shrub taxa, richness significantly increased but evenness and turnover remained consistent. Interestingly, however, there was a significant increase in abundance of shrubs at 70% of sites, including Calluna (heather), Ilex (holly) and Corylus (hazel), suggesting structural change. Surprisingly, there was no change in richness, evenness or turnover for herb taxa, possibly because change was highly variable spatially. However, there was a marked uptick in the disturbance indicator Plantago (plantain). Overall, these findings suggest that woodlands with sustained reduction in, or loss of, a tree species that once formed an important part of the canopy has profound, but often spatially idiosyncratic, impacts on vegetation diversity (richness), composition (evenness), stability (turnover), and on abundance of specific taxa, especially within the shrub layer. Use of this palaeoecological analogue, which was itself complicated by cooccurring changes in human activity, provides a valuable empirical insight into possible cascade effects of similar change in canopy opening in contemporary settings, including Ash Dieback. [ABSTRACT FROM AUTHOR]

Microorganisms in lakes are sensitive to salinity fluctuations. Despite extensive prior research on bacterial communities, our understanding of their characteristics and assembly mechanisms in lakes, especially in desert lakes with different salinities. To address this issue, we collected three samples from freshwater lakes, six from brackish lakes, and five from salt lakes in the Badanjilin Desert. The 16S rRNA gene sequencing was applied to investigate the bacterial interactions with rising salinity, community coexistence patterns, and assembly mechanisms. Our findings suggested that the increased lake salinity significantly reduces the bacterial community diversity and enhanced the community differentiation. Significant variations were observed in the contribution of biomarkers from Cyanobacteria, Chloroflexi, and Halobacterota to the composition of the lake bacterial communities. The bacterial communities in the salt lakes exhibited a higher susceptibility to salinity limitations than those in the freshwater and brackish lakes. In addition, the null modeling analyses confirmed the quantitative biases in the stochastic assembly processes of bacterial communities across freshwater, brackish, and saline lakes. With the increasing lake salinity, the significance of undominated and diffusion limitation decreased slightly, and the influence of homogenizing dispersal on community assembly increased. However, the stochasticity remained the dominant process across all lakes in the Badanjilin Desert. The analysis of co-occurring networks revealed that the rising salinity reduced the complexity of bacterial network structures and altered the interspecific interactions, resulting in the increased interspecies collaboration with increasing salinity levels. Under the influence of salinity stress, the key taxon Cyanobacteria in freshwater lakes (Schizothrix_LEGE_07164) was replaced by Proteobacteria (Thalassobaculum and Polycyclovorans) in brackish lakes, and Thermotogota (SC103) in salt lakes. The results indicated the symbiotic patterns of bacterial communities across varying salinity gradients in lakes and offer insights into potential mechanisms of community aggregation, thereby enhancing our understanding of bacterial distribution in response to salinity changes. [ABSTRACT FROM AUTHOR]

There are concerns over the effects of increasingly large and high‐severity fires that burn outside the local natural range of variation on ecosystem services and biodiversity.Pollinators provide important ecosystem services in the dry forests of the western United States where they depend on open habitat created or maintained by frequent, low‐ to moderate‐severity fire.We investigated the impact of burn severity on pollinator diversity in upland forest and meadow habitat at local (i.e., at the plot scale) and regional (burn severity class) spatial scales in the Sierra Nevada of California.In meadows, pollinator richness declined with increasing burn severity, but in uplands, there was no significant effect of burn severity on pollinator richness. Absence of pollinators was more likely to occur in unburned or high‐severity uplands.At the regional scale, we found that α was similar among burn classes in both habitats, although communities in burned uplands tended to be less even than unburned uplands. β was significantly higher in moderately burned than unburned upland habitat, but there were no significant differences in β for meadow habitats.Because meadows tend to be both more diverse and more sensitive to the negative impacts of high‐severity fire than uplands, conservation measures for pollinators could prioritise the removal of encroaching conifer species that may increase fire severity in these systems. [ABSTRACT FROM AUTHOR]

Aims: Post‐fire vegetation recovery is often determined by the similarity of post‐burn with unburned sites because of a lack of in situ information on pre‐fire communities. The inclusion of pre‐fire data can help account for pre‐existing differences and explore recovery also in terms of return to pre‐fire conditions. We used long‐term monitoring data in coastal sage scrub and grasslands to: (a) examine vegetation cover recovery of different functional groups; and (b) determine whether vegetation composition in burned areas has recovered in 4 years after fire with burned to unburned and pre‐ to post‐fire comparisons. Location: Orange County, California, USA. Methods: We analyzed long‐term vegetation monitoring (2007–2021) data from 39 grassland and 58 coastal sage scrub transects in southern California, including observations before and after the 2017 Canyon 2 fire. Linear mixed‐effect models were used to determine whether forb, grass, and shrub covers differed between burned and unburned sites while considering the effects of year and repeated monitoring. We used canonical analysis of principal coordinates to analyze vegetation composition based on burn status and time of sampling. Results: Whereas vegetation cover in grassland recovered quickly, native vegetation cover in burned coastal sage scrub remained lowered 4 years after fire, though forb and non‐native grass cover were higher in some post‐fire years. Community composition in burned coastal sage scrub was still in recovery 4 years after fire when compared with unburned or pre‐fire composition. Although burned and unburned grassland differed after fire in dominant grass species, inclusion of pre‐fire data showed that this was a pre‐existing difference. Conclusions: Coastal sage scrub had not recovered pre‐fire vegetation cover and composition by 4 years after fire, whereas grassland cover rebounded quickly, albeit with shifts in composition over time; patterns that were detected only by having pre‐ and post‐fire data from long‐term monitoring efforts. [ABSTRACT FROM AUTHOR]

The intricate mechanisms controlling plant diversity and community composition are cornerstone of ecological understanding. Yet, the role of mycorrhizal symbiosis in influencing community composition has often been underestimated. Here, we use extensive species survey data from 1315 grassland sites in China to elucidate the influence of mycorrhizal symbiosis on plant phylogenetic diversity and community assembly. We show that increasing mycorrhizal symbiotic potential leads to greater phylogenetic dispersion within plant communities. Mycorrhizal species predominantly influence deterministic processes, suggesting a role in niche‐based community assembly. Conversely, non‐mycorrhizal species exert a stronger influence on stochastic processes, highlighting the importance of random events in shaping community structure. These results underscore the crucial but often hidden role of mycorrhizal symbiosis in driving plant community diversity and assembly. This study provides valuable insights into the mechanisms shaping ecological communities and the way for more informed conservation that acknowledges the complex interplay between symbiosis and community dynamics. [ABSTRACT FROM AUTHOR]

Ditches are widespread and common elements of the agricultural landscape. Although they can provide habitats for aquatic biodiversity, their ecosystem integrity and processes are generally limited or even unknown due to anthropogenic pressures and the paucity of studies on this type of aquatic ecosystem. This study aimed to enhance the knowledge on the biodiversity, ecosystem attributes and ecological status of agricultural ditches by analyzing the macroinvertebrate communities of six different ditches and those of the main river in the same area. While negligible differences in taxonomic richness were observed, macroinvertebrate community composition significantly varied among sites as a function of the heterogeneous habitat conditions. These compositional differences strongly affected the relative abundance of functional feeding groups among sites and their derived ecosystem attributes. Moreover, the ecological status assessment depicted different scenarios depending on the biomonitoring indices applied. By means of a multifaceted, but still poorly adopted, analysis of the macroinvertebrate community, ranging from the taxonomic and functional diversity to ecosystem attributes and biomonitoring indices, the results obtained in this study offer useful information on the ecology of agricultural ditches with potential insights to improving their management. [ABSTRACT FROM AUTHOR]

Historical resurveys represent a unique opportunity to analyze vegetation dynamics over longer timescales than is typically achievable. Leveraging the oldest historical dataset of vegetation change in the Bavarian Alps, Germany, we address how environmental conditions, vegetation composition, and functional diversity in the calcareous grasslands of the Schachen region have changed across different elevational ranges over an 83‐year timeframe. We document changes in regional average temperature and precipitation. We use indicator values (IV) for species' ecological preferences and their palatability to grazers to infer local conditions (temperature, soil moisture/fertility, and grazing regime). We further estimate changes in temporal beta‐diversity and functional trait community composition between historical (1936) and contemporary (2019) surveys in two elevational (subalpine and alpine) belts. Both subalpine and alpine sites became drier; subalpine sites also became warmer with more palatable plants. Species occurrence and abundance in the Schachen region has not changed substantially over time despite changing macroclimate and local environmental conditions under anthropogenic change. Yet these grasslands have experienced several "invisible" changes in functional composition over the past 80 years. As the Schachen has become drier, species with traits related to drought tolerance and animal‐based dispersal have increased in dominance. Specifically, in alpine sites, community‐weighted means revealed that with low fecundity, higher potential for endo‐ and epizoochory (seed dispersal via animal gut and fur, respectively), higher foliar frost tolerance, and deeper dormancy increased in dominance. Similar trends were found for increasing dominance of low fecundity, epizoochorous species in subalpine sites. Vegetation data from resurveying historical plots in combination with changes in local conditions, classic biodiversity indices, and functional trait indices can provide more holistic insights into changes in the environment and potential impacts of those environmental changes on long‐term plant community and functional diversity. [ABSTRACT FROM AUTHOR]

Dam construction in natural rivers alters the intensity and frequency of water level fluctuations in reservoirs and their downstream river reaches, leading to the biotic homogenization of riparian communities. Although the intensity of dam‐induced water level fluctuations is often described qualitatively, quantitative analysis of its effects on riparian vegetation remains inadequate. This study compared riparian species dissimilarity between the natural Chishui River (as a control) and the regulated Wujiang River (with cascade reservoirs) to assess the level of biotic homogenization under different regulation types and in zones with different riverbank characteristics using the Bray–Curtis dissimilarity index. The reservoirs along the Wujiang River were classified into four different regulation types according to the water retention time, which were daily (0–7 days), weekly (7–30 days), seasonally (30–90 days), and yearly (>365 days). Results showed significant species dissimilarity in riparian vegetation along the Wujiang River compared to that along the Chishui River in the inundation, transitional, and unflooded zones. Furthermore, the species composition and dissimilarity patterns differed in the reservoirs and downstream rivers of the cascade dams in terms of regulation type and zone. For different regulation types, there was high species dissimilarity in both the upstream and downstream inundation zone of the daily reservoirs, while species dissimilarity was lower in both upstream and downstream of the yearly reservoir (Bray–Curtis index <0.5). This study provides a quantitative measure of how dam construction perturbs riparian vegetation communities, emphasizing the importance of the balance between the riparian ecosystem conservation and the economic demands of dam construction. [ABSTRACT FROM AUTHOR]

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African forest-savannah mosaics are complex landscapes holding mixtures of woody grasslands (savannah) and different forest systems (gallery forests and forest islands). In these landscapes, ants are highly diverse and perform essential ecosystem services, however, the assembly of ant communities in African forest-savannah mosaics is poorly understood. Here we showed the diversity and species overlap of ant communities in three habitats of the West African savannah and quantified the contribution of thermal tolerances and trophic ecology to community assembly. We investigated ant diversity in the West African Comoé National Park (Côte d'Ivoire) at 16 sites of three habitat types within a forest-savannah mosaic: continuous gallery forest, isolated forest islands and savannah. Across all sites, we collected a total of 91 species from 35 genera from three strata: trees, leaf litter, and soil. Additionally, we assessed differences in functional traits (trophic groups and thermal tolerance) between habitat types and strata. Though species richness was similar in all three habitats, there was a clear separation in species assemblages and functional traits between the two forest habitats and the savannah. Species assemblage shifts were primarily due to species turnover between savannah and forest habitats. In addition, the turnover in species assemblages from forests to savannah habitats was associated with a change in the thermal tolerance of species and in the proportion of trophobionts and predators. Forest and savannah habitats support distinct ant communities with different functional traits and contribute additively to the landscape-scale diversity of the West African ant fauna. Land-use and park management should focus on conserving both savannah and forest sites in tropical protected areas such as the Comoé National Park.

Summary: Redistribution of precipitation across seasons is a widespread phenomenon affecting dryland ecosystems globally. However, the impacts of shifting seasonal precipitation patterns on carbon (C) cycling and sequestration in dryland ecosystems remain poorly understood.In this study, we conducted a 10‐yr (2013–2022) field manipulative experiment that altered the timing of growing‐season precipitation peaks in a semi‐arid grassland.We found that the delayed precipitation peak suppressed plant growth and thus reduced gross ecosystem productivity, ecosystem respiration, and net ecosystem productivity due to middle growing‐season water stress. Surprisingly, shifting more precipitation to the early growing season can advance plant development, increase the dominance of drought‐tolerant forbs, and thus compensate for the negative impacts of middle growing‐season water stress on ecosystem C cycling, leading to a neutral change in grassland C sink.Our findings indicate that greater precipitation and plant development in spring could act as a crucial mechanism, maintaining plant growth and stabilizing ecosystem C sink. This underscores the urgent need to incorporate precipitation seasonality into Earth system models, which is crucial for improving projections of terrestrial C cycling and sequestration under future climate change scenarios. [ABSTRACT FROM AUTHOR]

High mountain freshwater systems are particularly sensitive to the impacts of global warming and relevant environmental changes. Microorganisms contribute substantially to biogeochemical processes, yet their distribution patterns and driving mechanism in alpine streams remain understudied. Here, we examined the bacterial and fungal community compositions in stream biofilm along the elevational gradient of 745–1874 m on Mt. Kilimanjaro and explored their alpha and beta diversity patterns and the underlying environmental drivers. We found that the species richness and evenness monotonically increased towards higher elevations for bacteria, while were non-significant for fungi. However, both bacterial and fungal communities showed consistent elevational distance-decay relationships, i.e., the dissimilarity of assemblage composition increased with greater elevational differences. Bacterial alpha diversity patterns were mainly affected by chemical variables such as total nitrogen and phosphorus, while fungi were affected by physical variables such as riparian shading and stream width. Notably, climatic variables such as mean annual temperature strongly affected the elevational succession of bacterial and fungal community compositions. Our study is the first exploration of microbial biodiversity and their underlying driving mechanisms for stream ecosystems in tropical alpine regions. Our findings provide insights on the response patterns of tropical aquatic microbial community composition and diversity under climate change. [ABSTRACT FROM AUTHOR]

As one of the world's most diverse ecosystems, coral reefs have been the focus of numerous biogeographic analyses. With strong biodiversity gradients across the Indo-Pacific, coral reefs have shed light on the effects of evolutionary history, isolation, and human exploitation on local assemblages. However, there are also strong environmentally driven local gradients in faunal assemblages. We ask, does reef fish community composition and trait space vary to a greater extent across small scales (i.e. along habitat gradients) or across large scales (i.e. across geographic regions separated by up to 12,000 km)? Using a standardized survey method that explicitly includes habitats (i.e. the slope, crest, and flat), we surveyed a highly diverse family of reef fishes (Labridae) in nine regions across the Indo-Pacific, from the Cocos (Keeling) Islands to French Polynesia. We demonstrate that small-scale habitat gradients represent a greater axis of variation, in both the taxonomic and trait composition of fish assemblages, than large-scale biogeographic gradients. Indeed, fish assemblages just 10 m apart, along a habitat gradient, appear to differ more than assemblages in the same habitats separated by over 12,000 km along the world's largest biodiversity gradient. Essentially, fish assemblages cluster by habitat regardless of their biogeographic region, with habitat associations trumping biogeographic affiliations. This emphasizes the primacy of local environmental factors, such as hydrodynamics, in shaping the ecology of reef fishes. It also raises serious concerns over the use of combined datasets, where data from different habitats are used, without explicit recognition, in global-scale analyses. [ABSTRACT FROM AUTHOR]

Land use influences soil biota community composition and diversity, and then belowground ecosystem processes and functions. To characterize the effect of land use on soil biota, soil nematode communities in crop land, forest land and fallow land were investigated in six regions of northern China. Generic richness, diversity, abundance and biomass of soil nematodes was the lowest in crop land. The richness and diversity of soil nematodes were 28.8 and 15.1% higher in fallow land than in crop land, respectively. No significant differences in soil nematode indices were found between forest land and fallow land, but their network keystone genera composition was different. Among the keystone genera, 50% of forest land genera were omnivores-predators and 36% of fallow land genera were bacterivores. The proportion of fungivores in forest land was 20.8% lower than in fallow land. The network complexity and the stability were lower in crop land than forest land and fallow land. Soil pH, NH4+-N and NO3−-N were the major factors influencing the soil nematode community in crop land while soil organic carbon and moisture were the major factors in forest land. Soil nematode communities in crop land influenced by artificial management practices were more dependent on the soil environment than communities in forest land and fallow land. Land use induced soil environment variation and altered network relationships by influencing trophic group proportions among keystone nematode genera.

Abstract Understanding the determinants of biodiversity in fragmented habitats is fundamental for informing sustainable landscape development, especially in urban landscapes that substantially fragment natural habitat. However, the relative roles of landscape and habitat characteristics, as emphasized by two competing frameworks (the island biogeography theory and the habitat diversity hypothesis), in structuring species assemblages in fragmented habitats have not been fully explored. This study investigated bird assemblages at 26 habitat patches (ranging in size from 0.3 to 290.4 ha) in an urban landscape, southwest China, among which habitat type composition and woody plant species composition varied significantly. Through 14 bird surveys conducted over six breeding seasons from 2017 to 2022, we recorded 70 breeding bird species (excluding birds recorded only once and fly-overs, such as raptors, swallows and swifts), with an average of 26 ± 10 (SD) species per patch. We found that patch area had significant direct and indirect effects on bird richness, with the indirect effects mediated by habitat richness (i.e., the number of habitat types). Isolation (measured as the distance to the nearest patch), perimeter to area ratio (PAR), and woody plant richness did not significantly predict variation in bird richness. Furthermore, none of these factors significantly sorted bird species based on their functional traits. However, the overall makeup of bird assemblages was significantly associated with the specific habitat types and woody plant species present in the patches. The results suggest that neither the island biogeography theory nor the habitat diversity hypothesis can fully explain the impacts of habitat fragmentation on bird richness in our study system, with their roles primarily being linked to patch area. The findings that habitat and plant compositions were the major drivers of variation in bird assemblage composition offer valuable insights into urban planning and green initiatives. Conservation efforts should focus not only on preserving large areas, but also on preventing urban monocultures by promoting diverse habitats within those areas, contributing to the persistence of meta-communities.

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A rapidly warming climate is driving changes in biodiversity worldwide, and its impact on insect communities is critical given their outsized role in ecosystem function and services. We use a long‐term dataset of North American bumble bee species occurrences to determine whether the community temperature index (CTI), a measure of the balance of warm‐ and cool‐adapted species in a community, has increased given warming temperatures. CTI has increased by an average of 0.99°C in strong association with warming maximum summer temperatures over the last 30 years with the areas exhibiting the largest increases including mid‐ to high latitudes as well as low and high elevations—areas relatively shielded from other intensive global changes. CTI shifts have been driven by the decline of cold‐adapted species and increases in warm‐adapted species within bumble bee communities. Our results show the pervasive impacts and ecological implications warming temperatures pose to insects. [ABSTRACT FROM AUTHOR]

Urbanisation has reduced the abundance and diversity of many taxonomic groups, and the effects may be more pronounced on islands, which have a smaller regional species pool to compensate. Green spaces within urban environments may help to safeguard wildlife assemblages, and the associated habitat heterogeneity can even increase species diversity. Here, total abundance and species diversity of butterflies, birds, and vegetation at nine rural and nine urban locations were quantified on Lipsi Island, Greece. Sites were assessed using Pollard walks for butterflies, point‐count surveys for birds, and quadrats for vegetation. There was no significant difference in the abundance or species diversity of butterflies or vegetation among rural and urban locations, which could pertain to the low building density within urbanised areas and the minimal extent of urbanisation on the island. However, urban areas hosted a significantly greater abundance, richness, and diversity of birds compared to rural sites. The community composition of butterflies, birds, and vegetation also differed significantly between urban and rural locations, highlighting the impact of urbanisation on species across a broad range of trophic groups. This study contributes to ecological knowledge on the impacts of urbanisation across multiple trophic levels in island ecosystems, with comparisons across a gradient of island size and urbanisation intensity needed in future research. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen (N) deposition has been substantially reduced due to declines in the reactive N emission in major regions of the world. Nevertheless, the impact of reduced N deposition on soil microbial communities and the mechanisms by which they are regulated remain largely unknown. Here, we examined the effects of N addition and cessation of N addition on plant and soil microbial communities through a 17‐year field experiment in a temperate grassland. We found that extreme N input did not irreversibly disrupt the ecosystem, but ceasing high levels of N addition led to greater resilience in bacterial and fungal communities. Fungi exhibited diminished resilience compared to bacteria due to their heightened reliance on changes in plant communities. Neither bacterial nor fungal diversity fully recovered to their original states. Their sensitivity and resilience were mainly steered by toxic metal ions and soil pH differentially regulating on functional taxa. Specifically, beneficial symbiotic microbes such as N‐fixing bacteria and arbuscular mycorrhizal fungi experienced detrimental effects from toxic metal ions and lower pH, hindering their recovery. The bacterial functional groups involved in carbon decomposition, and ericoid mycorrhizal and saprotrophic fungi were positively influenced by soil metals, and demonstrated gradual recovery. These findings could advance our mechanistic understanding of microbial community dynamics under ongoing global changes, thereby informing management strategies to mitigate the adverse effects of N enrichment on soil function. [ABSTRACT FROM AUTHOR]

Context: Human disturbance has transformed ecosystems globally, yet studies of the ecological impact of landscape modification are often confounded. Non-random patterns of land clearing cause differing vegetation types and soil productivity between fragments in modified landscapes and reference areas—like national parks—with which they are compared. Objectives: We sought to explore the influence of land modification on herpetofauna and small mammal communities using multiple biodiversity measures—species richness and diversity, individual species abundance, and community composition. We also aimed to investigate the role of traits such as diet, habitat breadth, and litter size in moderating species responses to land modification. Methods: We established 100 sampling sites to survey herpetofauna and small mammals in 11 fragments in an agricultural landscape compared to 11 ecologically equivalent ‘pseudo-fragments’ in a nearby national park in south-eastern Australia. We selected pairs of fragments and pseudo-fragments of the same size and vegetation type, and used identical survey methods to sample pairs simultaneously, thereby controlling for numerous confounding factors, such as differing vegetation type, weather, and survey effort. Results: Species richness and diversity were similar between fragments and pseudo-fragments. Despite this, we found community composition differed markedly—driven by the varying responses of individual species—indicating a shift in fauna communities associated with land modification. Fossorial habit, omnivorous diet, and broad habitat requirements led to higher abundance in fragments whilst arboreality, carnivorous diet, and narrow habitat requirements led to higher abundance in pseudo-fragments. Conclusions: Although fragments hold similar numbers of species to continuous areas, they contain distinct and novel communities, and sustain high abundances of some species. These diverse communities are dominated by native species, including threatened species, and their distinctive composition is shaped by traits conducive to persistence amidst land modification. These novel communities may provide a reservoir of resilience in the face of environmental change and should be viewed as complementary to conservation areas. [ABSTRACT FROM AUTHOR]

Purpose: Originally, the coastal region of East Africa was largely covered with coastal forest. With the human settlement, the majority of these forests have been transformed into agricultural land for subsistence farming. Today, only small and geographically isolated forest remnants exist and form a mosaic of different habitat types, including natural, semi-natural and anthropogenic ones. The forest remnants may still represent valuable habitats for typical forest plant and animal species. Methods: In this study, we surveyed hymenopteran diversity and community composition in different habitat types in southern Kenya. Hereby we considered a small remnant of East African coastal forest, adjoining orchards, shrublands, tree plantations, agricultural fields, and settlements. Hymenoptera represent a large variety of taxa and provide relevant ecosystem services such as pollination to the local people. Hymenoptera were collected with coloured pan traps, identified to family or genus level, and sorted to morphospecies. Habitat parameters such as dead wood, leaf litter, vegetation structure, and the availability of flowers has been assessed for each study site. Results: In total, we found 419 Hymenoptera individuals of 153 morphospecies. The different habitat types showed distinct species communities of Hymenoptera. Increasing shrub layer and increasing herb cover had a negative effect on hymenopteran species richness and abundance. Flowers, trees, leave litter, and deadwood showed no significant effect on hymenopteran diversity. Conclusion: Our results underline that small-scale habitat diversity lead to high overall diversity of Hymenoptera. Implications for insect conservation: The coastal forest remnant still holds a unique hymenopteran community with 20 Hymenoptera species exclusively found in this habitat type. It is thus of very high conservation value. [ABSTRACT FROM AUTHOR]

Habitat fragmentation and host community composition are implicated as key drivers of changing tick populations and tick‐borne pathogen dynamics, altering infection risk through coupled socioecological pathways that mediate interactions between tick vectors, vertebrate hosts, and humans. Patterns of host diversity may be particularly idiosyncratic across urbanized landscapes, due to trade‐offs between extreme fragmentation that reduces habitat suitability and access, and human activities that artificially increase resource availability for wildlife. We used camera and hair trap surveys and tick sampling to identify links between landscape composition and configuration, the mammalian host community, and the presence of three tick vector species at a human–wildlife interface in New York City, an emerging area within an endemic region for several tick‐borne diseases. We found that human infrastructures, such as the presence of fences in yards, could affect mammal host community composition by changing the "hardness" of edges between urban greenspaces and residential areas. We identified yard‐ and broader landscape‐level features associated with the presence of urban mammal species, and identified cascading effects of host community composition on tick distribution in yards, suggesting management implications for the mitigation of human exposure to tick‐borne pathogens. In particular, we identified a possible role of ubiquitous mesomammals, such as raccoons (Procyon lotor), in transporting Amblyomma americanum ticks between parks and neighboring residential yards, and confirmed the key role of white‐tailed deer (Odocoileus virginianus) for introducing Ixodes scapularis ticks into yards. Our results challenge assumptions that biodiversity loss in human‐modified areas always increases the risk for tick‐borne diseases. Instead, we found many residential sites had higher mammal species richness and higher detection of low reservoir competent ("dilution") hosts for Borrelia burgdorferi, such as opossums (Didelphis virginiana), than paired forested greenspaces. Our study highlights the importance of disentangling the mechanisms mediating tick‐borne disease hazard as a critical first step toward reducing urban tick‐borne disease risk. [ABSTRACT FROM AUTHOR]

Environmental factors mediating community change over time have been well documented for vascular plants, but not for their non‐vascular relatives, bryophytes. Elevation is one variable that has been explored regarding bryophyte community change wherein as elevation increases, bryophyte communities increase in diversity and abundance, whereas diversity and abundance decline for vascular plant communities. This begs the question, how might other environmental variables such as slope and aspect influence bryophyte communities, and how might these variables drive community changes over time? Our study focused on bryophyte communities in high elevation, spruce‐fir zones in the Great Smoky Mountains National Park (GSMNP), located in the Southeastern United States to answer this question. Plots established in 2007 were revisited and reinventoried in 2020. Comparisons were drawn to determine whether changes in bryophyte coverage corresponded to canopy cover change and environmental factors including elevation, slope, and aspect. Diversity and abundance at the two timepoints were analyzed. Alpha diversity and turnover across orders of q were compared for different elevation zones. Bryophyte alpha diversity at q = 0 significantly declined over time in association with elevation, but at q = 2, changes in alpha diversity varied according to changes in gap fraction, a measure of canopy cover, and slope. Bryophyte coverage remained stable except in the highest elevation zone dominated by fir trees where there was a decline in coverage predicted by aspect. There were high rates of turnover across all elevation zones regardless of Hill number. In contrast with other studies which examine how environmental variables mediate community changes at q = 0, the species richness of a community, our study shows that the environmental drivers of bryophyte community change vary depending on how abundance is weighted. [ABSTRACT FROM AUTHOR]

Urban bird species represent a subset of the regional species pool, consisting of species that have been able to survive in, or colonise, urban areas. Urban birds are typically resident non-forest species with a broad diet and nesting high in trees or in cavities, and some studies have also claimed that they are large-brained. However, little is known about how urban bird communities change over time. Does the urban environment impose specific selective pressures favouring particular species or ecological groups, or do birds in urban areas simply have population changes reflecting population trends at larger scales? We assessed population changes of 45 breeding land bird species in Oslo, the capital of Norway, based on surveys conducted ca. 15 years apart. Population changes within Oslo most closely matched changes occurring at the regional level (national population trends from Norway and Sweden). Thus, species increasing in Oslo were those that also increased at the regional level. We found no evidence that relative brain size, diet or habitat preferences influenced population trends. However, controlling for regional population trends, there were additional residual effects of nest site and migration: species nesting on the ground or low in bushes had more positive changes than species nesting high in trees or in cavities, and resident species did better than long- or short-distance migrants. These results indicate that urban environments are not isolated islands only influenced by own selection pressures, but are connected with regional population dynamics, most likely through immigration. [ABSTRACT FROM AUTHOR]

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

In aquatic ecosystems with low nutrient levels, organic aggregates (OAs) act as nutrient hotspots, hosting a diverse range of microbial species compared to those in the water column. Lake eutrophication, marked by intensified and prolonged cyanobacterial blooms, significantly impacts material and energy cycling processes, potentially altering the ecological traits of both free-living (FL) and particle-attached (PA) bacteria. However, the extent to which observed patterns of FL and PA bacterial diversity, community assembly, and stability extend to hypereutrophic lakes remains understudied. To address this gap, we investigated bacterial diversity, composition, assembly processes, and stability within hypereutrophic Lake Xingyun. Our results revealed that FL bacterial communities exhibited higher α-diversity than PA counterparts, coupled with discernible taxonomic compositions. Both bacterial communities showed distinct seasonality, influenced by cyanobacterial bloom intensity. Environmental factors accounted for 71.1% and 54.2% of the variation among FL and PA bacteria, respectively. The assembly of the PA bacterial community was predominantly stochastic, while FL assembly was more deterministic. The FL network demonstrated greater stability, complexity, and negative interactions, indicative of competitive relationships, while the PA network showed a prevalence of positive correlations, suggesting mutualistic interactions. Importantly, these findings differ from observations in oligotrophic, mesotrophic, and eutrophic lakes. Overall, this research provides valuable insights into the interplay among bacterial fractions, enhancing our understanding of nutrient status and cyanobacterial blooms in shaping bacterial communities. [ABSTRACT FROM AUTHOR]

Predator-prey interactions in marine ecosystems control population sizes, maintain species richness, and provide intermediate disturbance. Such ecosystem structuring interactions may be rare in Antarctic epibenthic communities, which are unique among marine ecosystems worldwide for their dominance of soft bodied fauna (sponges, soft and hard corals, and echinoderms) and a simultaneous paucity of shell crushing predators (sharks, rays and durophagous decapods). In the shallow benthos, instead of durophagy, important Antarctic predators such as starfish, pycnogonids (sea spiders), nemertean worms, and nudibranchs employ grazing, scavenging, or sucking strategies. Far less is known about deep sea (>1000 m) Antarctic benthic communities due to the challenging nature of polar data collection, so that photographic surveys provide one of the only means of making in situ observations of these deep sea communities. We used seabed photographs of the deep (~2000m) slope of the Powell Basin, northwest Weddell Sea, taken by the Ocean Floor Observation and Bathymetry System on board the RV Polarstern (PS118, April 2019) to investigate the epibenthic community composition, and Bayesian Network Inference (BNI) to determine the ecological network, namely the ecological associations, including potential invertebrate predator-prey relationships between taxa. Photographs show that the rocky substrates of the basin slope support between 10-22 morphotaxa per photo, and highly abundant communities (density between 106 to 553 individuals/m2). BNI results reveal a network of associations between the sessile and mobile suspension and filter feeding organisms and their physical environment. However, associations between invertebrate predators like starfish, and other organisms, were not detected in the network. This lack of inclusion within the network suggests that, despite the presence of these normally important mobile predators, invertebrate predator-prey interactions on the rocky Powell Basin slope do not have the same ecosystem-regulating impact that they do on shallow Antarctic epibenthic communities. [ABSTRACT FROM AUTHOR]

Aims: Climate warming at high altitudes occurs at an above‐average rate. Due to short geographical distances, warm‐adapted species might establish rapidly in mountain communities, while cold‐adapted specialists are likely to locally disappear, sometimes after a lag phase. Here, we investigate changes not only of the community composition of species‐rich mountain meadows, but also resulting alterations of their functional identity and diversity. Thereby, we hypothesize that transplantation to a warmer lowland environment leads to a shift towards a more acquisitive resource‐use strategy, caused by the immigration of lowland species. Temporarily this leads to an increase in functional diversity through the lagged extinction of high‐altitude species with conservative resource‐use strategies. Location: European Alps, Germany. Methods: Using a space‐for‐time substitution, we conducted a community transplant experiment at a high‐ and low‐elevation common garden site, where we compared the development of highland communities transplanted to the warmer low‐elevation site and control plant communities locally replanted at both sites over a period of 4 years after transplantation. In situ, we collected functional leaf morphological and biochemical traits based on which we calculated community weighted mean traits as well as community functional richness and functional divergence. Results: Species richness of the communities transplanted to the low‐elevation site increased over time, resulting from more species invasions than disappearances. This led to increasing similarity between transplanted highland communities and local lowland communities, and to greater functional richness and divergence 4 years after transplantation, although mean community traits did not diverge yet. Conclusions: Although the exposure to warmer temperatures did not immediately lead to the extinction of typical mountain meadow species, substantial community changes are expected through immigration of warm‐adapted species. Resulting changes in the functional characteristics of mountain communities are likely to modify competition regimes within these communities, which might accelerate the local extinction of mountain specialists. [ABSTRACT FROM AUTHOR]

Biological invasion is one of the major challenges to changing ecosystems worldwide. Red fire ants are a prime example of invasive soil animals. However, the impacts of their invasion on the native soil animal communities are still poorly understood. Here, we investigated how the biomass and diversity of soil microarthropods (incl., Collembola and Acari) vary between areas affected by red fire ants at different degrees (i.e., OA, occurrence area, 0–20 m from the nest; PCA, prevention and control area, 20–50 m; POA, potential occurrence area, 50–100 m). We also tested whether the potential effects of ant invasion on other animals are associated with changes in soil properties in the invaded areas. Our results showed a decline of 64% in species richness, 74% in density, and 72% in biomass of microarthropods in OA in comparison with POA. This reduction was mainly driven by the decrease of Acari, while no reduction in Collembola biomass was observed. Despite soil properties being significantly different between ant‐impacted areas, structural equation models indicated that the direct association of invasion with microarthropod communities is stronger than the indirect association mediated by soil properties. Therefore, we consider that direct biological interaction is more likely the major mechanism behind the observed changes in microarthropod communities. The effects of red fire ants were different among taxonomic and functional groups, with litter‐dwelling Collembola, Oribatida, and Mesostigmata (Acari) affected more negatively than soil‐dwelling and surface‐dwelling Collembola. Further, red fire ants affected the turnover component of beta‐diversity (i.e., replacement of species) for both Collembola and Acari. However, the impact on the nestedness component, which is related to species local extinction and population decline, was only detected for Acari. Our study shows that red fire ant invasion is associated with the depletion of soil microarthropod community, and especially highlights that Acari are more vulnerable to this invasion compared to Collembola. The divergent response between different taxonomic and functional groups of microarthropods and the consequent shift in microarthropod communities may have important significance to soil ecological functioning in the impacted areas. [ABSTRACT FROM AUTHOR]

Simple Summary: Research into the community composition and succession of blowflies can provide valuable insights into the timing and environmental conditions of colonization events, enhancing the accuracy of forensic analyses. Blowfly species diversity and distribution are influenced by various environmental factors such as season, habitat, and geographical location, which in turn affect their behavior and colonization patterns. The researchers surveyed blowfly populations across four distinct regions over the course of a year, examining how factors like season, habitat, and location influenced the blowfly community. The findings showed significant seasonal variations, emphasizing the impact of environmental conditions on blowfly behavior and colonization patterns. This research provides important regional data on forensically relevant blowfly species, which can help improve the accuracy of estimating the time and circumstances of death during criminal investigations. By enhancing our understanding of blowfly ecology, this work also contributes to broader scientific knowledge about decomposition processes and the role of insects in ecosystem functioning, ultimately benefiting crime scene investigations and advancing the field of forensic science. The study of blowfly (Diptera: Calliphoridae) biodiversity and distribution is crucial for forensic investigations. Abiotic and biotic factors, such as season and habitat type, have a significant impact on blowfly populations. However, only a few forensic entomology studies have been conducted in South Korea, particularly in the Gyeongsangnam-do region. To address this, an extensive year-long survey was conducted to analyze the compositions, habitat preferences, distribution, and seasonal abundance of forensically relevant blowflies in urban and forested habitats of Gyeongsangnam-do, with sampling conducted twice a month using mouse carcass-baited traps set for 48 h each time. A total of 3470 adult blowflies were recorded, encompassing five genera and 13 species, with a noted absence of specimens during the winter months. The predominant species was Lucilia porphyrina, accounting for 37.2% of the total sample, followed by Chrysomya pinguis (27.6%), Lucilia sericata (7.6%), and Lucilia illustris (7.1%). The species composition was consistent across all surveyed regions; however, seasonal variation in species diversity was evident, with a peak in spring and a decline in summer. Notably, certain species exhibited clear preferences for either urban (Calliphora calliphoroides and L. sericata) or forested habitats (L. porphyrina and Ch. pinguis). This pioneering study elucidates the diverse blowfly communities in Gyeongsangnam-do, highlighting significant seasonal and habitat-dependent variations. These findings enrich our understanding of blowfly ecology in this region, offering valuable insights for forensic applications and underscoring the necessity for ongoing entomological surveillance and research. [ABSTRACT FROM AUTHOR]

Simple Summary: There are differences in the cold resistance and anti-freeze compound levels in the two sexes of Pardosa astrigera, driving us to explore the differences in their intestinal microbiome. In this study, intestinal bacterial communities of P. astrigera in winter were compared using 16S rRNA high-throughput sequencing. The results showed significant differences in most alpha diversity indices and the relative abundances of dominant bacteria between males and females. Our research reveals the significant role of sex in shaping the diversity and composition of intestinal bacteria in overwintering P. astrigera. We suggest that Pseudomonas versuta (belonging to Proteobacteria) and Rhodococcus erythropolis (belonging to Actinobacteriota) may have the potential to play key roles in overwintering P. astrigera. Gut microbiota can promote the resistance of host arthropods to low-temperature stress. Female Pardosa astrigera have a lower anti-freeze compound level and weaker resistance to cold temperatures than the males in winter, which implies that their intestinal bacteria may be different during overwintering. This study primarily compared the intestinal bacterial communities between the two sexes of P. astrigera in a temperate region using 16S rRNA gene sequencing. Our findings indicated that the Chao1 and Shannon indices of intestinal bacteria in females were significantly higher than those in males, while the Simpson index in females was significantly lower than that in males. The male intestinal bacterial community was characterized by Proteobacteria and Actinobacteriota at the phylum level and by Pseudomonas and Rhodococcus at the genus level, with total relative abundances of 89.58% and 85.22%, respectively, which were also significantly higher than those in females, whose total relative abundances were 47.49% and 43.68%, respectively. In contrast, the total relative abundances of Bacteroidota and Firmicutes were significantly lower in males (4.26% and 4.75%, respectively) than in females (26.25% and 22.31%, respectively). Noteworthy divergences in bacterial communities were also found through an LEfSe analysis between females and males. Additionally, the results of the PICRUSt2 analysis showed that six out of eleven level-2 pathways related to key metabolic functions were significantly (or marginally significantly) higher in females than males, and five other level-2 pathways were significantly (or marginally significantly) lower in females than males. Our results imply that significant gender differences exist in intestinal bacterial communities of overwintering P. astrigera. We suggest that Pseudomonas versuta (belonging to Proteobacteria) and Rhodococcus erythropolis (belonging to Actinobacteriota) may have the potential to play key roles in overwintering P. astrigera. [ABSTRACT FROM AUTHOR]

Southern African grasslands with a rich flora, shaped by fire, grazing, climate and geology, as well as playing a role in carbon sequestration, are becoming more important in conservation. Fire is often used as a management tool to improve vegetation and to protect property against uncontrolled fire. We therefore attempt to determine the effect consecutive burning has on vegetation. Paired plots along firebreaks were used to collect vegetation data using the Braun-Blanquet cover abundance scale. Soil samples were also collected to determine the impact of fire on below-ground nitrogen (N) and carbon (C) stocks and ratios. The results indicate that there is no difference between the plant communities of the firebreaks and the adjacent grassland; however, there are certain species that are favoured by firebreaks and others by the adjacent grassland. There is also no difference in diversity between the firebreaks and adjacent grassland areas. Carbon and nitrogen stocks as well as C:N ratios did not differ significantly between the firebreaks and the adjacent grassland plots although trends indicate a decline in both C and N with repeated burning. [ABSTRACT FROM AUTHOR]

Detecting human impact on freshwater ecosystems is problematic without rigorous assessment of temporal changes. Assessments of mining impacts are further complicated by the strong influence of local catchment geology on surface waters even in unmined environments. Such influence cannot be effectively considered by using broad-scale reference frameworks based on regionalization and stream types. Using the BACI (Before-After Control-Impact) design, we examined the impact of mining discharges on freshwater algae and macroinvertebrate communities resulting from the rerouting of treated wastewaters through a pipeline to larger water bodies in Northern and North-Eastern Finland. Impacted sites and control sites were sampled 1 to 2 years before and 1 to 3 years after the pipelines became operational. Stream diatom communities recovered from past loadings upstream of the pipeline (which was no longer impacted by wastewaters) after rerouting of the wastewaters, while no changes downstream from the pipeline were detected. Upstream from the pipeline, diatom species richness increased and changes in relative abundances of the most common diatom taxa as well as in the overall community composition were observed. The effects of the pipeline were less evident for stream macroinvertebrate communities. There was an indication that regional reference conditions used in national biomonitoring may not represent diatom communities in areas with a strong geochemical background influence. Lake profundal macroinvertebrate communities were impacted by past loadings before the construction of the pipeline, and the influence of the pipeline was observed only as changes in the abundances of a few individual species such as phantom midges (which increased in abundance in response to discharges directed through the pipeline). Our results highlight the variable influence of mining discharges on aquatic communities. Statistically strong monitoring programmes, such as BACI designs, are clearly needed to detect these influences. [ABSTRACT FROM AUTHOR]

The response of microbiomes to salinity has been clarified in different geographic scales or ecosystems. However, how soil microbial community structure and interaction respond to salinity across wide salinity range and climatic region is still unclearly resolved. To address this issue, we examined the microbial community's composition in saline soils from two climatic regions (coastal wetland and arid desert). Our research confirms that soil salinity had a negative effect on soil nutrient content. Salinity decreased the relative abundance of bacteria, but increased archaea abundance, leading to the shifts from bacteria dominant community to archaea dominant community. Low-water medium-salinity soil (LWMS) had the most complex archaeal community network, whereas for bacteria, the most complex bacterial community network was observed in low-water high-salinity soils (LWHS). Key microbial taxa differed in three salinity gradients. Salinity, soil water content, pH, total nitrogen (TN), and soil organic carbon (SOC) were the main driving factors for the composition of archaeal and bacterial community. Salinity directly affected archaeal community, but indirectly influenced bacteria community through SOC; pH affected archaeal community indirectly through TN, but directly affected bacterial community. Our study suggests that soil salinity dramatically influences diversity, composition, and interactions within the microbial community. [ABSTRACT FROM AUTHOR]

Rhizosphere microbial community assembly results from microbe‐microbe‐plant interactions mediated by small molecules of plant and microbial origin. Studies with Arabidopsis thaliana have indicated a critical role of glucosinolates in shaping the root and/or rhizosphere microbial community, likely through breakdown products produced by plant or microbial myrosinases inside or outside of the root. Plant nitrile‐specifier proteins (NSPs) promote the formation of nitriles at the expense of isothiocyanates upon glucosinolate hydrolysis with unknown consequences for microbial colonisation of roots and rhizosphere. Here, we generated the A. thaliana triple mutant nsp134 devoid of nitrile formation in root homogenates. Using this line and mutants lacking aliphatic or indole glucosinolate biosynthesis pathways or both, we found bacterial/archaeal alpha‐diversity of the rhizosphere to be affected only by the ability to produce aliphatic glucosinolates. In contrast, bacterial/archaeal community composition depended on functional root NSPs as well as on pathways of aliphatic and indole glucosinolate biosynthesis. Effects of NSP deficiency were strikingly distinct from those of impaired glucosinolate biosynthesis. Our results demonstrate that rhizosphere microbial community assembly depends on functional pathways of both glucosinolate biosynthesis and breakdown in support of the hypothesis that glucosinolate hydrolysis by myrosinases and NSPs happens before secretion of products to the rhizosphere. Summary statement: This research demonstrates differential effects of lacking root nitrile‐specifier proteins and glucosinolate biosynthesis pathways on Arabidopsis rhizosphere microbiota. The results strengthen the hypothesis that glucosinolate hydrolysis in planta precedes secretion of products to the rhizosphere. [ABSTRACT FROM AUTHOR]

Conservation Translocation (CT), which includes reintroduction, reinforcement and introduction, is gaining momentum, responding to serious population decline in many orchids. Orchid conservation underpinned by a greater emphasis on understanding biotic and abiotic factors of habitats is critical for successful recovery and restoration programmes. Anacamptis morio, commonly known as green-winged orchid (GWO), is a terrestrial orchid found throughout Europe, but populations in England rapidly declined in its native range in the last several decades. The current study explored the relationship between soil abiotic characteristics and the community composition of key fungal groups. Wild sites in Essex and Cumbria in England, where successful colonies are currently present, were compared to potential sites for CT in Cumbria. The Cumbrian sites managed by cattle grazing include the wild site and three potential CT sites, with two of them hosting no GWO plants. The Essex site, fOxley Meadow, where no cattle is used for grassland management, hosts the largest population of GWO in England. The aim of this study was to understand whether the community composition of fungi and soil characteristics of the potential CT sites in Cumbria are nearly compatible with that of Oxley Meadow. Oxley Meadow, with around 65,000 plants, stands out as a unique habitat compared to all Cumbria sites, as it showed low organic content. Nitrate and phosphate content were smaller for Oxley Meadow compared to other Cumbrian sites. The proportion of Basidiomycota fungi was greater in Oxley Meadow compared to all Cumbrian sites where Ascomycota dominated. The abundant fungal group found in Oxley Meadow was Agaricales. From Agariclaes, Hygrophoraceae or waxcaps fungi are considered an indicator group of fungi and were the most abundant group in Oxley Meadow. They have a negative correlation with targeted key fungal groups and abiotic parameters. More in-depth assessments using additional primers are essential to better understand the fungal diversity and how this diversity translates to the resilience of orchid habitats. This preliminary study points to future studies to assess whether sites are near-compatible to the wild site where large colonies are present using additional primers collected over different time scales. [ABSTRACT FROM AUTHOR]

Diversity and functionality of bird communities in tropical agroforests are shaped by their surrounding landscape, particularly the extent and type of natural forest. However, most evidence comes from tropical rainforest landscapes, whereas the bearing of such trends in other forest types remains understudied. We compared functional and beta diversity of bird communities in 23 cacao agroforests embedded in landscapes of two contrasting Peruvian regions: seasonally‐dry tropical forests and subtropical rainforests from the Andean foothills. Strong climatic seasonality affects both landscapes, but forest vegetation structure and complexity differ. We found higher bird species richness (n = 179 spp) and higher species turnover in the subtropical forest than in the dry forest landscape (n = 64 spp). Only in the dry forest landscape, distance from forest increased dissimilarity driven by species loss, that is, the nestedness component of beta diversity. This points to the importance of conserving dry tropical forests within the broader landscape matrix, with known benefits for pest control and cacao yield. Functional diversity indices were not influenced by forest distance in either landscape, but the proportion of insects in birds' diet decreased by 27% along a 1 km distance gradient from forest in the subtropical forest landscape. In the dry forest landscape, however, it decreased by only 3% across the same distance gradient. Far from forest (≥1 km), forest specialization decreased by ~33% and 20% in the subtropical and dry forest landscapes, respectively. These differences indicate that regionally‐adapted agroforest management is paramount for conserving bird diversity and ecosystem services as pest control. Procuring high‐canopy shade trees and adequate microhabitats for insectivorous species is essential to maintain biocontrol services in the subtropical forest. Conversely, in the dry forest enhancing low‐canopy vegetation with a focus on frugivores and ensuring forest closeness to agroforests may maximize bird diversity and their ecosystem services. A complete version of this article is translated to Spanish in the supplements. [ABSTRACT FROM AUTHOR]