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Background: Panax ginseng cultivated under the forest is popular because its shape and effective ingredients are similar to wild ginseng. The growth of P. ginseng in the larch forest is generally better than in the broad-leaved forest, and the incidence rate of diseases is low. Therefore, the selection of forest species is one of the basic factors in the successful cropping of P. ginseng. Methods: Illumina HiSeq high-throughput sequencing was used to analyze the 16S rRNA/ITS gene sequence of P. ginseng rhizosphere soil under larch forest to study the rhizosphere microbiome's diversity and community composition structure. Results: The species classification and richness of rhizosphere bacterial and fungal communities in the same-aged P. ginseng were similar. Consistent with the soil system of commonly cultivated crops, Proteobacteria, Actinobacteriota, Acidobacteriota, Verrucomicrobiota, Chloroflexi, and Basidiomycota, Ascomycota were the dominant phylum of bacteria and fungi, respectively. Compared with the soil without planting P. ginseng, the diversity of microorganisms and community structure of continuous planting for 2 years, 5 years, and 18 years of P. ginseng rhizosphere soil had little change. The accumulation levels of Ilyonectria, Fusarium, Gibberella, and Cylindrocarpon were not significantly increased with planting P. ginseng and the increased age of cropping P. ginseng. Conclusions: The results of this study showed that the soil function of the larch forest was good, which provided a theoretical basis for the land selection and soil improvement of cultivating P. ginseng under the larch forest. [ABSTRACT FROM AUTHOR]

Ectomycorrhizal (ECM) fungi play fundamental roles in host plant growth and terrestrial ecosystems. Cedrus deodara is cultivated in several regions in China, has high ecological, economic and medicinal value, for its afforestation and providing timber and wood oil. Here, we investigated ECM colonization status of four urban C. deodara forests in Nantong, East China. We also characterized soil spore banks by conducting bioassay experiments using soils collected from these forests. In total, we identified 19 ECM fungal species, of which 13 species were found in mature forests and 9 species were identified in bioassay experiments, with only 3 species shared. Soil pH and available P content had significant effects on species occurrence in both mature trees and bioassay seedlings on local scales. ECM communities clearly (A = 0.391, p = 0.006) separated mature forests from spore banks. Thelephoracae was the richest family we detected associated with C. deodara, while Trichophaea sp. was the most dominant in mature forests, and Wilcoxina sp. was dominant in spore banks. ECM richness affected the growth of bioassay seedlings, especially after inoculation with 2 ECM species, promoting root growth, significantly (F = 3.028, p = 0.050), but it had no effects on shoots (F = 1.778, p = 0.177). No effect of inoculation rate was found on seedlings growth. To conserve this important tree species, the ECM fungi that are associated with it should be considered. [ABSTRACT FROM AUTHOR]

Despite the well-documented role of biochar in promoting soil quality and crop productivity, the underlying biological mechanisms remain poorly understood. Here, we explored the effects of straw biochar on soil microbiome in the rhizosphere from wheat using metagenomic sequencing. Our results showed that straw return decreased the yields of wheat, while the straw biochar return increased the wheat yields. Further, both the richness and community composition confirmed different effects of the straw return and straw biochar return. The straw biochar return also resulted in greater rhizosphere effects from wheat, represented by resource availability, including soil organic carbon, soil total nitrogen, available phosphorus, and available potassium. The rhizosphere effects from wheat, represented by microbial metabolism genes involved in carbon, nitrogen, phosphorus, and potassium cycling, however, were decreased by straw biochar returning. In addition, the rhizosphere effects from nitrogen content and the nitrogen cycling genes showed negative relationships with wheat yields. Together, these results revealed that straw biochar enhanced soil resource availability but suppressed microbial metabolism genes in the rhizosphere from wheat, supporting the idea that straw biochar serves as a nutrient pool for crops. [ABSTRACT FROM AUTHOR]

[Objectives] This study investigated the regulation of soil fungal diversity and community assembly processes by Myxococcus sp. BS in tobacco-rice rotation fields, and provided theoretical guidance for biological control through the application of Myxococcus sp. BS with organic fertilizer in the tobacco-rice rotation fields. [Methods] This experiment consisted of three treatments: no treatment (CK), application of Myxococcus sp. BS (BS) and application of Myxococcus sp. BS and organic fertiliser (BF). The community diversity, composition and assembly processes of soil fungi were analysed through high-throughput sequencing technology. [Results] After the addition of Myxococcus sp. BS, Chaol index decreased while Shannon index increased. The similarity of fungal communities between BS and BF treatment was high, while the similarity between CK and Myxococcus sp. BS treated soil was low. At the phylum level, the relative abundances of Mortierellomycota, Chytridiomycota and Glomeromycota decreased after the addition of Myxococcus sp. BS. At the genus level, the relative abundance of Ustilaginoidea and Cladosporium increased while the relative abundance of Alternaria, Humicola and Mortierella gradually decreased. Significant differences in fungal abundance between treatments were obtained by LEfSe analysis (i.e., biomarker), with seven genera having significantly changed in CK, five in BS, and eight in BF. In all three treatments, the processes of fungal community assembly were dominated by stochastic processes, of which dispersal limitation contributed the most, and the contribution of stochastic process increased with the addition of Myxococcus sp. BS. [Conclusions] The addition of Myxococcus sp. BS to tobacco-rice rotation fields changed the soil fungal diversity, community composition and assembly process, resulting in a significant reduction in the relative abundance of Alternaria, which caused diseases of tobacco and rice; and the effect of applying Myxococcus sp. BS with organic fertilizer was better than that of applying Myxococcus sp. BS agent alone. [ABSTRACT FROM AUTHOR]

A trait‐based community assembly framework has great potential to direct ecological restoration, but uncertainty over how traits and environmental factors interact to influence community composition over time limits the widespread application of this approach. In this study, we examined how the composition of seed mixes and environment (north‐ vs. south‐facing slope aspect) influence functional composition and native plant cover over time in restored grassland and shrubland communities. Variation in native cover over 4 years was primarily driven by species mix, slope aspect, and a species mix by year interaction rather than an interaction between species mix and slope aspect as predicted. Although native cover was higher on wetter, north‐facing slopes for most of the study, south‐facing slopes achieved a similar cover (65%–70%) by year 4. While community‐weighted mean (CWM) values generally became more resource conservative over time, we found shifts in particular traits across community types and habitats. For example, CWM for specific leaf area increased over time in grassland mixes. Belowground, CWM for root mass fraction increased while CWM for specific root length decreased across all seed mixes. Multivariate functional dispersion remained high in shrub‐containing mixes throughout the study, which could enhance invasion resistance and recovery following disturbance. Functional diversity and species richness were initially higher in drier, south‐facing slopes compared to north‐facing slopes, but these metrics were similar across north‐ and south‐facing slopes by the end of the 4‐year study. Our finding that different combinations of traits were favored in south‐ and north‐facing slopes and over time demonstrates that trait‐based approaches can be used to identify good restoration candidate species and, ultimately, enhance native plant cover across community types and microhabitat. Changing the composition of planting mixes based on traits could be a useful strategy for restoration practitioners to match species to specific environmental conditions and may be more informative than using seed mixes based on growth form, as species within functional groups can vary tremendously in leaf and root traits. [ABSTRACT FROM AUTHOR]

Artificial light at night (ALAN) is a growing global problem altering the behavior of organisms and thereby community composition and ecosystem processes. Research has mostly focused on terrestrial ecosystems, but a growing number of studies show that aquatic ecosystems are increasingly affected. Here, we provide a conceptual framework that describes how ALAN can influence aquatic ecosystems through effects on the behavior of ecologically important invertebrates. These organisms provide a range of critical ecological functions, from serving as food for other organisms to nutrient cycling and the translocation of energy and matter within and between ecosystems. In addition, we systematically searched the literature to assess the current state of the field and identify knowledge gaps. The literature search reveals that an increasing number of studies find light pollution to alter the behavior of aquatic invertebrates, such as their movements, habitat choice, and foraging behavior, but that the fitness consequences of these behavioral changes are largely unknown, as are their impacts on populations, communities, and ecosystems. Yet, assessing the consequences of behavioral changes for higher ecological levels is of vital importance given the central role of these invertebrates in ecosystems. Thus, more research needs to be directed to the ecological consequences of behavioral responses of aquatic invertebrates to light pollution. Overall, more effort should be made to assess the ecological consequences of behavioral responses to ALAN, and, importantly, how negative effects of light pollution could be mitigated. Significance statement: Light pollution is of growing ecological concern and influencing ecosystems through effects on the behavior of organisms. Aquatic ecosystems are increasingly exposed and an ecologically important group of organisms in these systems are invertebrates. Here, we discuss how artificial light at night alters the behavior of aquatic invertebrates and how this in turn influences ecosystem structure and function. Such an understanding of the mechanisms and pathways that underlie the effect of light pollution on aquatic ecosystems is needed if we are to develop efficient strategies to reduce negative effects of human-made lighting systems on ecosystems. [ABSTRACT FROM AUTHOR]

Biodiversity and ecosystem function (BEF) studies aim to understand how ecosystems respond to a gradient of species diversity. Generalised Diversity‐Interactions (DI) models are suitable for analysing the BEF relationship. These models relate an ecosystem function response of a community to the identity of the species in the community, their evenness (proportions) and interactions. The number of species in the community (richness) is included implicitly in a DI model.It is common in BEF studies to model an ecosystem function as a function of richness; while this can uncover trends in the BEF relationship, by definition, species diversity is broader than richness alone, and important patterns in the BEF relationship may remain hidden. Here, we introduce the DImodels R package for implementing DI models. We show how richness is mathematically equivalent to a simplified DI model under certain conditions, and illustrate how using the DI multidimensional definition of species diversity can provide deeper insight to the BEF relationship compared to traditional approaches.Using DI models can lead to considerably improved model fit over other methods; it does this by incorporating variation due to the multiple facets of species diversity. Predicting from a DI model is not limited to the study design points, the model can interpolate or extrapolate to predict for any species composition and proportions (assuming there is sufficient coverage of this space in the study design).Expressing the BEF relationship as a function of richness alone can be useful to capture overall trends. However, collapsing the multiple dimensions of species diversity to a single dimension (such as richness) can result in valuable ecological information being lost. DI modelling provides a framework to test the multiple components of species diversity in the BEF relationship. It facilitates uncovering a deeper ecological understanding of the BEF relationship and can lead to enhanced inference. The open‐source DImodels R package provides a user‐friendly way to implement this modelling approach. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of substrate type in macroinvertebrate assemblages in Mediterranean lakes. Samplings have taken place in the littoral zone of 21 lakes in Greece, between 2015 and 2018. We compared benthic macroinvertebrate assemblages among three substrate types of their littoral zones; sandy, covered with macrophytes and stony substrate. Benthic macroinvertebrate assemblages at sites with extended macrophyte cover differed only slightly in composition and abundance from the ones found in stony and sandy substrates. Coenagrionidae were indicative of sites covered with macrophytes and Oligochaeta and Erpobdellidae were representative of stony substrates. The type of substrate proved to be a statistically significant factor influencing the number of benthic macroinvertebrate taxa, the relative abundance of Oligochaeta and the relative abundance of Odonata. In the context of designing site-adapted management measures, priority could be given to the conservation and restoration of aquatic vegetation in lake littoral zones, which host rich macroinvertebrate assemblages with abundant taxa of Odonata. [ABSTRACT FROM AUTHOR]

Abstract Purpose Arbuscular mycorrhizal fungi (AMF) play a key role in medicinal plant species, besides their ecological role in shaping plant communities. Knowledge about the diversity and structure of AMF communities associated with the endangered Prunus africana is valuable in the conservation and domestication of the species for its medicinal products. Methods We investigated the diversity and structure of AMF species communities in the rhizosphere soils of P. africana trees occurring in four fragmented Afromontane forests found in Cameroon (Mount Cameroon and Mount Manengouba) and Kenya (Chuka and Malava) using Illumina Miseq sequencing of 18S rRNA gene amplicons. Results A total of 64 virtual taxa (VT) belonging to eight genera were detected, namely Glomus (43 VT), Claroideoglomus (6 VT), Paraglomus (5 VT), Acaulospora (4 VT), Diversispora (3 VT), and Archaeospora, Pacispora, and Scutellospora with 1 VT each. Scutellospora heterogama VTX00286 was the most abundant and common species in all four sites (49.62%). Glomeraceae and Gigasporaceae were the most abundant families found across the sites, while Acaulosporaceae, Pacisporaceae, and Archaeosporaceae were rare, represented by

Abstract Background Apolygus lucorum is a worldwide omnivorous pest damaging a range of crops and causing great economic losses. Symbiotic bacteria living in insects play a key role in the nutrition, physiology, and behavior of hosts. Here, we present an experiment using Illumina HiSeq sequencing targeting the V3–V4 regions of bacteria’s 16S rRNA throughout the entire life cycle of A. lucorum. Results The first and second instar nymphs have the largest alpha diversity compared with other life stages of the insect. Bacterial phyla Proteobacteria (72.29%), Firmicutes (15.24%), Actinobacteria (7.76%) exhibit the largest relative abundance in all developmental stages. Erwinia (23.97%) and Lactococcus (10.62%) are the two genera with the highest relative abundance. The relative abundance of Erwinia in the nymph stage is significantly greater than the adult stage, and the relative abundance of Lactococcus in 6-day-old and 9-day-old adult females is higher compared with adult males. Conclusions These results reveal that microbial community composition and relative abundance shift dynamically at different life stages, implying that different bacterial phyla and genera may have specific roles in specific life stages such as metabolism, nutrition absorption, detoxification, and reproduction. This study reveals for the first time the community composition and ecological dynamics of symbiotic bacteria throughout the life stages of A. lucorum, and thus may provide insight to new strategies for pest control.

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.

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

Abstract Understanding the influence of fine-scale abiotic filters on plant communities can provide important insights into floristic patterns of the Brazilian Cerrado. We aimed to evaluate the interactions of the soil and the plant community composition with their distribution in different sandy environments of Brazilian Cerrado, the Jalapão region. Eight environments were sampled, each with ten plots of 20 × 50 m. All woody individuals presenting circumference at soil height ≥ 10 cm were sampled. Subplots of 5 × 15 m were demarcated, where woody individuals with a circumference at soil height ≥ 5 and < 10 cm were sampled. Subplots of 2 × 2 m were also demarcated to sample herbaceous individuals. Soil samples varying from 0 to 20 cm of depth were collected for each plot (20 × 50 m). Overall, 20000 individuals that belong to 338 species and 76 families were sampled. The dominant family was Fabaceae. There were significant differences among the environments regarding species richness and soil. The analyzed soils are extremely poor and with a tendency to sandy texture, small chemical and/or physical variations imply differences in the distribution of vegetation. Our study revealed abiotic filters exerted crucial fine-scale effects on plant community in the Jalapão region.

Urban development has drastically altered ecosystems with dramatic effects on avian diversity and community structure. Most studies investigating this phenomenon are conducted in large and established cities, with fewer conducted in areas of current urbanization. Measuring avian community structure in recently established and growing cities is necessary to understand which species are being affected in a range of urban environments. There is also a critical need to explore multiple measures of urbanization, as different axes of human influence might have varied effects on wildlife. This study investigated the relationship between avian communities and urban noise, light, and landscape composition in Weld County, CO, one of the United States’ fastest growing metropolitan areas. We tested the general hypothesis that avian community assemblages would vary with multiple urban characteristics. We measured noise, light, and landscape composition across 16 sites ranging from urban to non-urban and paired these data with avian species census data. We used multivariate analyses to test for covariance of our three measures of urban characteristics, and to examine patterns of species presence and abundances at sites. Results suggest that developed land and water covary with avian community structure across our study sites. Anthropogenic noise and light did not drive avian community patterns as strongly as percent developed land and water. These three urban characteristics did not covary or form a linear urban to non-urban gradient, suggesting that urbanization can have patchy and unpredictable effects, highlighting the value of measuring urban characteristics separately.

This study attempted to explore the adaptability of gut microbiota in grass carp to diets with different carbohydrate-to-protein ratios in order to better understand the immunological and metabolic changes in the organism. Three different ratios of carbohydrate and protein diets (12.5%-carbohydrate 46.3%-protein (LCHP), 27.5%-carbohydrate 33.7%-protein (MCMP), and 42.5%-carbohydrate 16.9%-protein (HCLP)) were satiety-fed to grass carp. After feeding, the growth performance, gut microbial community composition and function were analyzed. Growth performance results showed that LCHP group exhibited the significantly lower specific growth ratio than MCMP group, and HCLP group displayed the significantly higher feed coefficient and lower survival rate. The community composition results showed that the abundance of the beneficial genus Cetobacterium was the highest in MCMP group, and the abundance of the harmful genera Ruminiclostridium_9 and Phreatobacter was the highest in the LCHP and HCLP groups, respectively. Furthermore, the ratio of Firmicutes to Bacteroidetes considered as an indicator of gut microbiota dysfunction, was significantly higher in the LCHP and HCLP groups than that in the MCMP group. The community functional analysis showed that the abundance levels of cofactors and vitamin metabolism were significantly lower and the abundance levels of neurodegenerative diseases were significantly higher in the LCHP and HCLP groups than those in the MCMP group. The abundance levels of energy metabolism and a range of biomolecules metabolism were significantly decreased in the HCLP group. These results suggested that high-carbohydrate diets have a greater negative impact on the gut microbiota than high-protein diets. The gut microbiota results echoed the growth performance parameters, reflecting that gut microbiota may play an important role in the influence of different carbohydrate-to-protein ratios diets on host. Bacterial genera such as Ruminiclostridium_9 and Phreatobacter may play key roles in the effects of high-protein and high-carbohydrate diets on host health and metabolism, respectively.

Previously unknown pathogens often emerge from primary ecosystems, but there is little knowledge on the mechanisms of emergence. Most studies analyzing the influence of land-use change on pathogen emergence focus on a single host–pathogen system and often observe contradictory effects. Here, we studied virus diversity and prevalence patterns in natural and disturbed ecosystems using a multi-host and multi-taxa approach. Mosquitoes sampled along a disturbance gradient in Côte d’Ivoire were tested by generic RT-PCR assays established for all major arbovirus and insect-specific virus taxa including novel viruses previously discovered in these samples based on cell culture isolates enabling an unbiased and comprehensive approach. The taxonomic composition of detected viruses was characterized and viral infection rates according to habitat and host were analyzed. We detected 331 viral sequences pertaining to 34 novel and 15 previously identified viruses of the families Flavi-, Rhabdo-, Reo-, Toga-, Mesoni- and Iflaviridae and the order Bunyavirales. Highest host and virus diversity was observed in pristine and intermediately disturbed habitats. The majority of the 49 viruses was detected with low prevalence. However, nine viruses were found frequently across different habitats of which five viruses increased in prevalence towards disturbed habitats, in congruence with the dilution effect hypothesis. These viruses were mainly associated with one specific mosquito species (Culex nebulosus), which increased in relative abundance from pristine (3%) to disturbed habitats (38%). Interestingly, the observed increased prevalence of these five viruses in disturbed habitats was not caused by higher host infection rates but by increased host abundance, an effect tentatively named abundance effect. Our data show that host species composition is critical for virus abundance. Environmental changes that lead to an uneven host community composition and to more individuals of a single species are a key driver of virus emergence.

Epiphytic microalgae are important contributors to the carbon and nutrient cycles yet are often overlooked during ecological surveys. In reef habitats, epiphytes are often found living on host organisms, including seaweeds or corals, and can influence community composition of higher trophic level taxa. Hence, understanding how epiphytes respond to different reef substrate materials can help inform designs of substrates intentionally deployed to form artificial reefs which can encourage high biodiversity and ecological functioning. One such epiphyte, Gambierdiscus spp., is a harmful benthic dinoflagellate which produces toxins that bioaccumulate and cause ciguatera fish poisoning (CFP) when contaminated fish is consumed by humans. CFP is one of the most frequently reported seafood-associated illnesses around the world, occurring most often near tropical reefs. We surveyed the epiphytes amongst 13 natural and artificial reef sites located off the coast of North Carolina to determine the role of the reefs’ foundational substrate (e.g., natural marl, steel or concrete) on structuring the epiphyte community with an emphasis on Gambierdiscus spp. abundance. No Gambierdiscus spp. were detected among the sampled reefs, likely due to suboptimal water temperatures. An ex-situ substrate preference experiment for Gambierdiscus spp. was performed using marl to represent natural rocky reefs, and steel and concrete to represent artificial reefs. Experimental results indicated that Gambierdiscus spp. grew fastest in the presence of marl and density decreased significantly when exposed to steel. However, steel artificial reefs had the highest average epiphyte biomass and species richness amongst the sampled reefs. 18s rRNA gene sequence analysis revealed that natural reefs were more likely to be dominated by dinoflagellates, whereas steel and concrete reefs were dominated by diatoms. We found that epiphyte composition was related to material at a phylum level, but seaweed hosts played a more significant role at the species level. These findings suggest that CFP risk is relatively low on the reefs studied but natural reefs would likely be preferentially colonized by Gambierdiscus spp. should ambient conditions become appropriate.

Svalbard is one of the fastest warming regions in the Arctic including massive loss in fjord sea ice both in terms of area coverage, ice thickness and duration. Sea ice is a habitat for a wide variety of microscopic flora and fauna, and we know little about the impact of accelerated loss of sea ice on this unique sea ice community. Here, we present the first study on the seasonal progression and spatial distribution of the sympagic meiofauna community, in a Svalbard fjord. Further, the meiofauna community in sea ice versus the water column below were compared to investigate the link between the two habitats. In total, we found 12 taxa associated with the sea ice and 15 taxa in the water column below with 11 taxa occurring in both habitats. However, a Canonical-analysis (CA) showed that despite similarities in taxa the two mediums were distinctly different (potentially) due to the low abundance of ice nematodes and polychaete juveniles, in pelagic samples. Temporally, ice meiofauna abundances ranged from 9.7 to 25.3 x 103 ind m-2 from beginning of March to end of April, following the seasonal build-up of ice algal biomass from 0.02 to 15.99 mg Chl a m-2 during the same time span. For the transect stations, the lowest ice meiofauna abundance was recorded at the outermost station (VMF2) with 1.6 x 103 ind m-2 and the highest abundance at the mid-station MS with 25.3 x 103 ind m-2. Our results indicate that fjord ice harbors most ice algae and sympagic meiofauna in its lower 10-cm with highest values in the lowermost 2-cm, at the sea ice water interface. Sympagic meiofauna communities were mostly dominated by nematodes or polychaete juveniles. We observed the phenology of ice nematodes through the maturation of females and hatching of juveniles from eggs. Polychaete larvae developed (quickly) into juveniles and grew morphological features indicative of readiness for settlement. Thus, we propose, that as with other parts of the Arctic, sea ice in Svalbard fjords plays an important role in the life cycle of ice nematodes and for accelerating the growth of polychaete larvae. Loss of coastal sea ice may therefore negatively impact coastal biodiversity and affect recruitment for some benthic infauna in Svalbard.

Marine phytoplankton fuel the oceanic biotic chain, determine the carbon sequestration levels, and are crucial for the global carbon cycle and climate change. In the present study, we show a near-two-decadal (2002-2022) spatiotemporal distribution of global phytoplankton abundance, proxy as dominant phytoplankton taxonomic groups (PTGs), with a newly developed remote sensing model. Globally, six chief PTGs, namely chlorophytes (~26%), diatoms (~24%), haptophytes (~15%), cryptophytes (~10%), cyanobacteria (~8%), and dinoflagellates (~3%), explain most of the variation (~86%) in phytoplankton assemblages. Spatially, diatoms generally dominate high latitudes, marginal seas, and coastal upwelling zones, whereas chlorophytes and haptophytes control the open oceans. Satellite observations reveal a gentle multi-annual trend of the PTGs in the major oceans, indicative of roughly "unchanged" conditions on the total biomass or compositions of the phytoplankton community. Jointly, "changed" status applies to a short-term (seasonal) timescale: (1) Fluctuations of PTGs exhibit different amplitudes among different subregions, together with a general rule-more intense vibration in the Northern Hemisphere and polar oceans than other zones; (2) diatoms and haptophytes vary more dramatically than other PTGs in a global-scale scope. These findings provide a clear picture of the global phytoplankton community composition and can improve our understanding of their state and further analysis of marine biological processes. [ABSTRACT FROM AUTHOR]

Background: Fungicides are frequently used in agriculture and can enter freshwater ecosystems through multiple pathways. The negative impacts of fungicides on microorganisms, fungi in particular, and their functions such as leaf decomposition have been repeatedly shown. In our previous microcosm experiment with three consecutive cycles of fungicide exposure and colonisation of leaf substrate, we found clear functional changes, but no differences in fungal community structure could be detected using morphological identification by analysing the spores of aquatic hyphomycetes. In this study, we examined the effects on fungal and bacterial community composition in detail using ITS and 16S metabarcoding and comparing the results to morphologically assessed community composition. Results: While we found fewer species with metabarcoding than with morphological identification, metabarcoding also enabled the identification of several fungal species that were otherwise unidentifiable morphologically. Moreover, by distinguishing individual amplicon sequence variants (ASVs) metabarcoding provided greater taxonomic resolution. In line with the morphological results, metabarcoding neither revealed effects of fungicides on the aquatic hyphomycetes nor on the total fungal or bacterial community composition. However, several ASVs responded significantly to fungicides, demonstrating variable tolerances within species. Conclusions: Overall, the absence of detectable effects of fungicides on the community structure despite clear functional effects, suggests a complex relationship between community structure and the ecosystem function of leaf decomposition. [ABSTRACT FROM AUTHOR]

Simple Summary: This research investigates moth biodiversity in two southern Swedish provinces, Västergötland and Småland, spanning from 1974 to 2019. The moth diversity over these years was evaluated using data collected from literary sources. To augment this dataset, a light trap was installed in each province in 2020. The data demonstrate enhanced diversity in Kalmar, Småland, and a more rapid colonisation rate throughout the study period in Småland compared to Västergötland. Noteworthily, our traps in Västergötland and Småland captured 44% and 28% of the known moth species in these provinces, respectively. We reveal significant associations between the probability of species presence in the traps and specific traits when contrasted with a provincial species pool. Traits disproportionately represented in the traps encompass species with considerable variation in colour patterns, generalist habitat and host plant preferences, extended flight periods, and species that primarily overwinter as eggs. This research underscores the influences of climate change and human activities on the shaping of moth biodiversity. As moths are vital components of ecosystems and serve as important bioindicators, understanding the dynamics of their communities and the factors influencing these dynamics, such as anthropogenic impacts, is crucial to understand the ecological processes. Our study focuses on two provinces in southern Sweden, Västergötland and Småland, where we used province records from 1974 to 2019 in combination with light traps (in 2020) to record the presence and abundance of moth species, subsequently assessing species traits to determine potential associations with their presence in anthropogenically modified landscapes. This study design provides a unique opportunity to assess temporal changes in moth communities and their responses to shifts in environmental conditions, including anthropogenic impacts. Across the Västergötland and Småland provinces in Sweden, we recorded 776 moth taxa belonging to fourteen different taxonomic families of mainly Macroheterocera. We captured 44% and 28% of the total moth species known from these provinces in our traps in Borås (Västergötland) and Kalmar (Småland), respectively. In 2020, the species richness and abundance were higher in Borås than in Kalmar, while the Shannon and Simpson diversity indices revealed a higher species diversity in Kalmar. Between 1974 and 2019, the colonisation rates of the provinces increased faster in Småland. Ninety-three species were found to have colonised these provinces since 1974, showing that species richness increased over the study period. We reveal significant associations between the probability of a species being present in the traps and distinct traits compared to a provincial species pool. Traits over-represented in the traps included species with a high variation in colour patterns, generalist habitat preferences, extended flight periods, lower host plant specificity, and overwintering primarily as eggs. Our findings underscore the ongoing ecological filtering that favours certain species-specific traits. This study sheds light on the roles of climate change and anthropogenic impacts in shaping moth biodiversity, offers key insights into the ecological processes involved, and can guide future conservation efforts. [ABSTRACT FROM AUTHOR]

Understanding how species richness changes along elevational gradients has attracted increasing attention from many researchers. The relationships between species richness and elevations were characterized by monotonic decreases or mid-elevational peaks. The western Sichuan Plateau is an important species diversity hotspot. However, there is little information available about the ant species diversity and distribution patterns of this region. In this study, we hypothesize that ant diversity will show a monotonic decrease from mid-elevation with increasing elevation. Here, the ant species diversity and distribution patterns of this region were investigated by plot surveys. A total of 22,645 ants were collected from eight elevational transects in the central and northern parts of the western Sichuan Plateau, which were identified as belonging to 40 species, 18 genera, and 4 subfamilies. We found a unimodal relationship between elevation and ant species richness, with the highest ant species richness occurring at mid-elevations. The similarity coefficient of ant communities in each elevational transect was at a moderate level of dissimilarity, indicating that the elevation difference and habitat heterogeneity had a great impact on ant communities in the central and northern areas of the western Sichuan Plateau. [ABSTRACT FROM AUTHOR]

Combined studies of the communities and interaction networks of bird and insect pollinators are rare, especially along environmental gradients. Here, we determined how disturbance by fire and variation in sugar resources shape pollinator communities and interactions between plants and their pollinating insects and birds. We recorded insect and bird visits to 21 Protea species across 21 study sites and for 2 years in Fynbos ecosystems in the Western Cape, South Africa. We recorded morphological traits of all pollinator species (41 insect and nine bird species). For each site, we obtained estimates of the time since the last fire (range: 2–25 calendar years) and the Protea nectar sugar amount per hectare (range: 74–62 000 g/ha). We tested how post‐fire age and sugar amount influence the total interaction frequency, species richness and functional diversity of pollinator communities, as well as pollinator specialization (the effective number of plant partners) and potential pollination services (pollination service index) of insects and birds. We found little variation in the total interaction frequency, species richness and functional diversity of insect and bird pollinator communities, but insect species richness increased with post‐fire age. Pollinator specialization and potential pollination services of insects and birds varied differently along the environmental gradients. Bird pollinators visited fewer Protea species at sites with high sugar amount, while there was no such trend for insects. Potential pollination services of insect pollinators to Protea species decreased with increasing post‐fire age and resource amounts, whereas potential pollination services of birds remained constant along the environmental gradients. Despite little changes in pollinator communities, our analyses reveal that insect and bird pollinators differ in their specialization on Protea species and show distinct responses to disturbance and resource gradients. Our comparative study of bird and insect pollinators demonstrates that birds may be able to provide more stable pollination services than insects. [ABSTRACT FROM AUTHOR]

Saccharum yield decline results from long-term monoculture practices. Changes in cropping management can improve soil health and productivity. Below-ground bacterial community diversity and composition across soybean (Glycine max (L.) Merr) cover crop, Saccharum monoculture (30+ year) and fallowed soil were determined. Near full length (~1,400 base pairs) of 16S rRNA gene sequences were extracted from the rhizospheres of sugarcane and soybean and fallowed soil were compared. Higher soil bacterial diversity was observed in the soybean cover crop than sugarcane monoculture across all measured indices (observed operationational taxonomic units, Chao1, Shannon, reciprocal Simpson and Jackknife). Acidocateria, Proteobacteria, Bacteroidetes and Planctomycetes were the most abundant bacterial phyla across the treatments. Indicator species analysis identified nine indicator phyla. Planctomycetes, Armatimonadetes and candidate phylum FBP were associated with soybean; Proteobacteria and Firmicutes were linked with sugarcane and Gemmatimonadetes, Nitrospirae, Rokubacteria and unclassified bacteria were associated with fallowed soil. Non-metric multidimensional scaling analysis showed distinct groupings of bacterial operational taxonomic units (97% identity) according to management system (soybean, sugarcane or fallow) indicating compositional differences among treatments. This is confirmed by the results of the multi-response permutation procedures (A = 0.541, p = 0.00045716). No correlation between soil parameters and bacterial community structure was observed according to Mantel test (r = 211865, p = 0.14). Use of soybean cover-crop fostered bacterial diversity and altered community structure. This indicates cover crops could have a restorative effect and potentially promote sustainability in long-term Saccharum production systems. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is an essential element for plant growth, however, whether the aboveground net primary productivity (ANPP) of typical steppe was limited by P remains obscure. To detect the effects of P addition on primary productivity and aboveground biomass of different plant functional groups both under ambient and N addition conditions, ANPP and aboveground biomass of grasses and forbs were measured from 2016 to 2020 on a 16-year N and P addition experiment platform in a temperate typical steppe in Inner Mongolia. The soil available N and P concentrations were also determined to test the relationship between ANPP and the availability of soil nutrients. We found that P addition under ambient condition had no significant effect on ANPP and the aboveground biomass of grasses and forbs. However, under N addition, P addition significantly increased ANPP and the aboveground biomass of forbs. Furthermore, soil available N and P concentrations were increased significantly by N and P addition, respectively. Moreover, there was no significant correlation between ANPP and soil available P concentration, while ANPP was positively correlated with soil available N concentration. These results suggest that P is not the key factor limiting the primary productivity of the temperate typical steppe in Inner Mongolia. However, under N addition, P addition can promote ANPP and alter the community composition. These findings provide valuable information for the management of the temperate typical steppe. [ABSTRACT FROM AUTHOR]

Community composition is limited by a species' ability to reach, establish and survive on a site. Establishment and survival are constrained by both abiotic conditions and biotic interactions that operate together on local scales. They decide which species from the pool will form the community. For this reason, it is very important to clearly define the species pool, against which the community composition is compared.The effect of biotic and abiotic factors can be assessed experimentally, and the species pool by using estimation methods based on broad‐scale observational data. We compared success of five species pool estimation methods in predicting establishment and survival in a seed/transplant addition experiment.In four different locations, we added resident and non‐resident species to plots with and without competition and tested the ability of the species to thrive in both competition‐free gaps (constrained mainly by abiotic conditions) and in intact vegetation (complete community filter). In these treatments, we studied the seedling recruitment and survival, and the establishment and survival of pregrown transplants. The ability of species pool assessment methods to predict species performance in individual treatments was compared. The comparison of results from individual treatments indicates the importance of individual components of the community filter.Species pool assessment methods, based on species co‐occurrence patterns (Beals index, favourability and unconstrained ordination), were the best predictors of species performance in the intact vegetation, but were less successful in the competition‐free environment. Methods based on co‐occurrence patterns were the most effective for predicting seedling establishment, while seed germination alone and transplant survival were poorly predictable.The biotic filter was the principal factor defining our community composition, especially for the process of seedling establishment. The roles of biotic and abiotic filters are very difficult to distinguish without an experimental approach and the ratio of their importance changes during plant ontogenesis. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Questions: How does long‐term, moderate‐intensity mowing affect plant community diversity, biomass, and composition in semi‐arid grasslands? And what are the underlying mechanisms that drive differences in plant community structure and functions between mowed and unmowed grasslands? Location: A semi‐arid grassland in Jilin Province, northeastern China. Methods: In a 30‐year experiment, we investigated long‐term effects of mowing on the grassland ecosystem in northeastern China by comparing plant community diversity, biomass, and composition between mowed and unmowed permanent plots across six grasslands. Results: Long‐term mowing did not affect plant species richness, but increased species evenness by 29%. Mowing had little effects on above‐ground (shoot) and below‐ground (root) biomass. The unchanged above‐ground biomass in the mowed areas was attributed to a trade‐off between biomass of grasses and forbs: mowing significantly increased forb biomass by 50%, but reduced grass biomass by 20% and the grass to forb biomass ratio by 46%. Mowing also reduced biomass of the dominant Leymus chinensis grass by 24% and litter biomass by 56%. Regression analyses indicated that the species evenness was negatively affected by L. chinensis biomass and litter biomass. Conclusions: This study demonstrates that, although long‐term moderate mowing has limited effects on plant species richness and plant biomass, such a managed strategy can greatly reduce the dominance of grass species and allow the growth of forb species, leading to a higher species evenness in the plant community. This win–win situation promotes forage production for farmers while increasing plant diversity for conservation, suggesting that current mowing tactics can be a sustainable management practice in this ecosystem. However, the continuous loss of plant litter because of mowing may have negative influences on soil nutrient availability in the long run. From this perspective, a short‐term halt in mowing or fertilization that allows plants and soil nutrients to recover could represent a more optimal protocol for management. [ABSTRACT FROM AUTHOR]

Rodents (Rodentia) are the most abundant and diverse order of mammals, present in all habitats, including urban areas. The traffic linked to globalisation has favoured their involvement in biological invasions that have an impact on local biodiversity, the economy and human health. In Franceville, Gabon, little is known about the rodent community. We therefore studied the composition and distribution of rodents along a gradient highlighting the heterogeneity of the city's landscape. The three habitat types studied showed no difference in small mammal abundance, while the diversity index was higher in the vegetated habitat (SDI = 0.73) compared to the outdoor (SDI = 0.71) and indoor (SDI = 0.45) habitats. Our work shows the importance of vegetal remnants in the city for the maintenance of native species. It also highlights the impact of introduced species on small mammal assemblages and the need for management to reduce the factors of their proliferation. [ABSTRACT FROM AUTHOR]

Seed fungal endophytes play a crucial role in assisting the overall health and success of their host plant; however, little is known about the factors that influence the diversity and composition of these endophytes, particularly with respect to how they change over time and within urban environments. Using culturing techniques, morphological analyses, and Sanger sequencing, we identified the culturable seed fungal endophytes of Banksia ericifolia at two urban and two natural sites in Sydney, New South Wales, Australia. A total of 27 Operational Taxonomic Units were obtained from 1200 seeds. Older cones were found to contain, on average, more colonised endophytes than younger cones. Species richness was also significantly influenced by cone age, with older cones being more speciose. Between urban and natural sites, the overall community composition did not change, although species richness and diversity were greatest at urban sites. Understanding how these endophytes vary in time and space may help provide an insight into the transmission pathways used and the potential role they play within the development and survival of the seed. This knowledge may also be crucial for restoration purposes, especially regarding the need to consider endophyte viability in ex situ seed collection and storage in seed-banking practices. [ABSTRACT FROM AUTHOR]

In 2015, the communities of reef-associated motile macrocrustaceans (decapods and stomatopods) were compared between two coral reefs with contrasting levels of degradation in Puerto Morelos (Mexican Caribbean), "Limones", less degraded, with a healthy live coral cover, and "Bonanza", more degraded, with less live coral and more macroalgae. Since then, several stressors have impacted Puerto Morelos. Massive influxes of floating Sargassum, which reached record levels in 2018, 2021, and 2022, have exacerbated the already high eutrophication of the reef lagoon. An outbreak and rapid propagation of the Stony Coral Tissue Loss Disease in 2018 changed the functionality of reefs. Three back-to-back hurricanes struck the coast close to Puerto Morelos in October 2020 and another one in August 2021. We repeated the study in 2022 to examine the potential changes in the habitat and communities of reef-associated crustaceans since 2015. Reef degradation did not increase significantly between 2015 and 2022, but crustacean species richness, diversity, evenness, and dominance, which differed between reefs in 2015, became similar between reefs in 2022, as did the crustacean community composition. The abundance of herbivore crabs increased in Limones, displacing the coral- and hydrocoral-mutualistic crabs and the abundance of detritivore hermit crabs increased in Bonanza. These results suggest a taxonomic homogenization between reefs, apparently related to subtle ecological changes not necessarily captured by standard metrics of reef condition. [ABSTRACT FROM AUTHOR]

Saline and hypersaline wetlands account for almost half of the volume of inland water globally. They provide pivotal habitat for a vast range of species, including crucial ecosystem services for humans such as carbon sink storage and extractive resource reservoirs. Despite their importance, effective ecological assessment is in its infancy compared to current conventional surveys carried out in freshwater ecosystems. The integration of environmental DNA (eDNA) analysis and traditional techniques has the potential to transform biomonitoring processes, particularly in remote and understudied saline environments. In this context, this preliminary study aims to explore the potential of eDNA coupled with conventional approaches by targeting five hypersaline lakes at Rottnest Island (Wadjemup) in Western Australia. We focused on the invertebrate community, a widely accepted key ecological indicator to assess the conservational status in rivers and lakes. The combination of metabarcoding with morphology-based taxonomic analysis described 16 taxa belonging to the orders Anostraca, Diptera, Isopoda, and Coleoptera. DNA-based diversity assessment revealed more taxa at higher taxonomic resolution than the morphology-based taxonomic analysis. However, certain taxa (i.e., Ephydridae, Stratyiomidae, Ceratopogonidae) were only identified via net surveying. Overall, our results indicate that great potential resides in combining conventional net-based surveys with novel eDNA approaches in saline and hypersaline lakes. Indeed, urgent and effective conservational frameworks are required to contrast the enormous pressure that these ecosystems are increasingly facing. Further investigations at larger spatial-temporal scales will allow consolidation of robust, reliable, and affordable biomonitoring frameworks in the underexplored world of saline wetlands. [ABSTRACT FROM AUTHOR]

Aim: Attempts over the past 30 years to explain geographical variation in the strength of herbivore pressure have given rise to ecological hypotheses like the latitudinal herbivory hypothesis. This hypothesis, however, has rarely been tested using community‐level data. Therefore, the aim of our study was to examine the patterns and potential mechanisms underlying geographical variation in community‐wide herbivory. Location: The Qinghai‐Tibetan Plateau. Time Period: July 2021. Major Taxa Studied: Plants. Methods: We selected 43 grassland sites along a 1500‐km latitudinal gradient (c. 27°N to 39°N) and a 2698‐m elevational gradient (1886–4584 m) on the Qinghai‐Tibetan Plateau. We evaluated geographical patterns in invertebrate herbivory pressure at the population and community levels, while also evaluating the importance of geographical variation in mediating the effects of abiotic and biotic factors on intraspecific variation (through changes in herbivory on component species) and species turnover effects (through changes in plant community composition). Results: Community‐wide herbivory decreased with latitude, mirroring intraspecific variation, while species turnover effects did not vary along any tested geographical gradients. Furthermore, we found that geographical variation in community‐wide herbivory was strongly positively correlated with soil nitrogen content. We also found a positive effect of soil nitrogen content on intraspecific variation and a negative effect of plant community biomass on species turnover effects. Main Conclusions: The latitudinal gradient in community‐wide herbivory was primarily mediated by intraspecific variation, which was in turn associated with a gradient in soil nitrogen content. Our findings highlight the need for community‐wide assessments of geographical variation in plant–herbivore interactions, decomposing community‐wide herbivory into intraspecific variation and species turnover effects. [ABSTRACT FROM AUTHOR]

Aim: Efforts to predict the responses of soil fungal communities to climate change are hindered by limited information on how fungal niches are distributed across environmental hyperspace. We predict the climate sensitivity of North American soil fungal assemblage composition by modelling the ecological niches of several thousand fungal species. Location: One hundred and thirteen sites in the United States and Canada spanning all biomes except tropical rain forest. Major Taxa Studied: Fungi. Time Period: 2011–2018. Methods: We combine internal transcribed spacer (ITS) sequences from two continental‐scale sampling networks in North America and cluster them into operational taxonomic units (OTUs) at 97% similarity. Using climate and soil data, we fit ecological niche models (ENMs) based on logistic ridge regression for all OTUs present in at least 10 sites (n = 8597). To describe the compositional turnover of soil fungal assemblages over climatic gradients, we introduce a novel niche‐based metric of climate sensitivity, the Sørensen climate sensitivity index. Finally, we map climate sensitivity across North America. Results: ENMs have a mean out‐of‐sample predictive accuracy of 73.8%, with temperature variables being strong predictors of fungal distributions. Soil fungal climate niches clump together across environmental space, which suggests common physiological limits and predicts abrupt changes in composition with respect to changes in climate. Soil fungi in North American climates are more likely to be limited by cold and dry conditions than by warm and wet conditions, and ectomycorrhizal fungi generally tolerate colder temperatures than saprotrophic fungi. Sørensen climate sensitivity exhibits a multimodal distribution across environmental space, with a peak in climates corresponding to boreal forests. Main Conclusions: The boreal forest occupies an especially precarious region of environmental space for the composition of soil fungal assemblages in North America, as even small degrees of warming could trigger large compositional changes characterized mainly by an influx of warm‐adapted species. [ABSTRACT FROM AUTHOR]

Ecological monitoring has been recognized as a key tool for guiding biofouling management practices. A two-year study was designed to collect comprehensive data on the biofouling community progression at Port Canaveral, Florida, using clear recruitment panels and a scanner to directly observe organisms attached to the surface. This method allowed for minimal disruption to the natural community development and aided the collection of a suite of metrics to explore environmental relationships. Seasonal changes in community composition and biofouling pressure, especially at earlier stages, were related to abiotic conditions. Interannual variation within seasonal communities was also observed. The type of dominant organism present impacted the rate at which surfaces were covered (e.g. fastest cover with tunicates) and the overall biomass accumulation (e.g. highest rate with tubeworms). Results highlight that understanding the influence of the time of year and the dominant organism identity is ecologically vital for improving biofouling management. [ABSTRACT FROM AUTHOR]

Ecological disturbances act as environmental filters by removing species with particular characteristics, resulting in community types associated with different disturbance histories. However, studies to date on community responses to disturbance have neglected the potential for different community assemblages to display different responses. Using lotic invertebrate communities as a study system, this study investigated the influence of community composition on disturbance response. We undertook a 26-h stream channel experiment to test how distinct invertebrate community types (an undisturbed spring community, flood-disturbed community, and agriculture-disturbed community), shaped by specific disturbance histories and characterised by different species with particular functional groups, responded to additional disturbance of varying types and combinations (an undisturbed control, high-flow, nutrients, sediment, and a combined sediment and nutrients treatment). Invertebrate drift was used as a diagnostic tool to assess community responses. Significant three-way interactions were identified for total invertebrate drift, drift of typically sensitive taxa (Ephemeroptera, Plecoptera and Trichoptera) and drift of cased organisms between community type, disturbance type and time, indicating that disturbance history and corresponding community type influenced community response to disturbance. Differing responses to disturbance between community types were often characterised by specific taxa, likely driven by adaptive traits, but also by phenotypic plasticity and altered biotic interactions. Community responses to the multiple disturbance scenario suggested potential for interactive effects, with differing responses potentially driven by species co-tolerance mechanisms. When determining the impacts of disturbance, our results suggest there is insight to be gained from a broader perspective incorporating multiple community types into future research. This approach could also improve management outcomes, facilitating tailored restoration and conservation strategies. [ABSTRACT FROM AUTHOR]

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Recent studies have shown a decoupling in the way community composition and functions respond to environmental changes. A common pattern observed is that aggregated functions at the community level are more stable than community composition, which is likely the result of functional compensatory dynamics driven by interspecific differences in response to environmental change. However, the mechanisms by which these patterns emerge remain largely unexplored. Here we investigated in a mesocosm experiment for four weeks the compositional and functional responses of edible phytoplankton (<64 μm) and cladoceran zooplankton communities to climate warming (a constant increase of +3.5°C plus heat wave) and eutrophication (nutrient additions) from a size‐based perspective. Our results show that warming increases small‐sized taxa and decreases large‐sized taxa within both phytoplankton and zooplankton community composition. We found that such opposite responses of different‐sized taxa contributed to the stability of planktonic community functions and thereby resulted in a decoupling between compositional and functional changes. We also found that nutrient additions increased the abundance of all‐sized algal taxa, while phytoplankton community function remained stable. Nutrient additions did not alter the zooplankton community, neither compositionally nor functionally. Under the combined stress of warming and nutrient additions, the compositional and functional responses of planktonic communities were mainly driven by warming. In a broader perspective, our findings reveal a size‐dependent compensation mechanism and suggest that functional stability relies on compensatory effects among different‐sized taxa, and it is therefore important that communities host a large range of taxa differing in size to withstand an increasingly more variable environment in the future. [ABSTRACT FROM AUTHOR]

Salinity gradient directly influences the composition and distribution of biological communities from upstream to downstream of the estuary. In this middle-scale study, a large dataset (10 rocky sections of 3 islands) of the Hangzhou Bay and Zhoushan Sea allowed thoroughly analyzing salinity and seasonal gradients and relating macrobenthos distributions and community structure to environment factors. In general, distinct regional differences were found in the distribution, diversity and community structures of macrobenthos. Abundance and biomass in all regions were dominated by suspension feeders and increased along the estuarine gradient. Significant seasonal differences were found in the abundance and biomass of herbivores, and significant regional differences were found in the abundance and biomass of suspension feeders. Redundancy analysis showed that water temperature was the dominant factor for the low-salt region, suspended particulate matter was the dominant factor for the mid-salt region, and water temperature as well as chlorophyll-a were the dominant factors for the high-salt region. These results showed that at a middle-scale estuary a considerable fraction of the variation in distribution and community structure of the intertidal macrobenthos correlated very well with environmental factors (salinity, water temperature, chlorophyll-a and suspended particulate matter). [ABSTRACT FROM AUTHOR]

Biological soil crusts (BSCs) are a dominant ecological landscape of drylands, which have a significant impact on global biogeochemical flux. However, it is unclear how bacterial community and physiological characteristics vary along the BSCs successional stages. In this study, bacterial community composition, physiological characteristics, and monosaccharide composition of extracellular polysaccharides (EPSs) were compared among different successional stages. Our findings demonstrated that besides the dominant bacterial species, the bacterial communities also showed considerable differences between these two stages. Cyanobacteria were keystone taxa in the early stage, while heterotrophic bacteria (Proteobacteria, Actinobacteria and Acidobacteria) were keystone taxa in the later stages. According to the results of CO2 exchange, cyanobacterial crusts accumulated net carbon faster than moss crusts, while moss crusts had a significantly higher respiration rate. The monosaccharide analysis indicated that the EPSs components also varied depending on BSCs' successional stages. Specifically, the contents of rhamnose and arabinose were higher in the cyanobacterial crusts than other types of crusts, while the contents of fucose, xylose, mannose and glucose were the highest in cyanobacterial-lichen crusts, and galactose content was highest in the moss crusts. Altogether, our results stress the heterogeneous variation of BSCs along with succession, and this work offered a fresh viewpoint for a deeper comprehension of the interactions between the monosaccharide components of EPS and the networks of bacterial communities in BSCs. [ABSTRACT FROM AUTHOR]

Background. The Cerrado is a neotropical savannah with high mammalian diversity where wildfires are rather common and highly relevant to its ecological patterns and processes. The effects of fire on Cerrado mammals, however, are poorly understood. Aims. We investigated the effects of an unplanned large wildfire (burned area ~66 000 ha) on medium and large mammals in a Cerrado area in Brazil, focusing on fire-driven changes in community composition up to 3 years after fire. Methods. We evaluated burned and unburned sites before and after the wildfire, using 54 camera traps between 2017 and 2020. Total trap effort was 6334 days (unburned areas) and 7670 days (burned areas). Key results. We recorded 25 species in burned and 19 in unburned areas. Fire markedly affected the community up to 3 years after burning. A canonical correspondence analysis indicated that herbivores (tapirs and pampas deer) were common in the burned areas, with an increase in the relative abundance of carnivores the second year after fire. Conclusions. Communitylevel responses were complex, with guild-dependent changes and effects still detected 3 years after fire. Implications. Management strategies that include patch mosaic burns (with areas unburned and burned 1 and 2 years earlier) could contribute to maintenance of local mammal diversity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Plant invasions are a global concern. In eastern China, bamboo is rapidly expanding, negatively influencing neighbouring forest communities. However, studies on how bamboo invasion affects belowground communities, especially for soil invertebrates, are still lacking. In the present study, we focused on a highly abundant and diverse fauna taxon – Collembola. Collembola communities have three typical life‐forms (i.e., epedaphic, hemiedaphic, and euedaphic) inhabiting different soil layers and playing distinct roles in ecological processes. Specifically, we studied their abundance, diversity, and community composition at the three stages of bamboo invasion: uninvaded secondary broadleaf forest, moderately invaded mixed bamboo forest, and completely invaded bamboo (Phyllostachys edulis) forest. RESULTS: Our results showed that bamboo invasion negatively influenced Collembola communities by decreasing their abundance and diversity. Moreover, Collembola life‐forms differed in their responses to bamboo invasion, with surface‐dwelling Collembola being more vulnerable to bamboo invasion than soil‐living Collembola. CONCLUSION: Our findings indicate differential response patterns to bamboo invasion within Collembola communities. The negative effects of bamboo invasion on soil surface‐dwelling Collembola may further influence ecosystem functioning. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Biodiversity loss is a main challenge for agricultural sustainability. Major drivers include local management and landscape simplification. Therefore, conservation measures aim to increase organic agriculture, reduce pesticide use, and increase the proportion of semi-natural habitats (SNH). Yet, it is important to understand the effects of such measures. We investigate how arthropod biomass, taxa richness, and community composition in Malaise trap samples are affected by organic management, pesticide use, and SNH in the landscape. The 32 studied vineyards were chosen in a crossed design of management (organic vs. conventional) and pesticide use (regular vs. reduced) along a gradient of landscape composition. Pesticide reduction by 55% was obtained by including half of the vineyards with fungus-resistant grape (FRG) varieties. Malaise trap samples were weighed and arthropods identified using metabarcoding. Surprisingly, biomass was almost one-third higher in conventionally managed vineyards compared to organic ones. Taxa richness increased by more than one third when the proportion of SNH in a radius of 1,000 m in the surrounding landscape increased from zero to 50%. Diptera richness tended to be 4% higher in conventionally managed vineyards and the richness of Hymenoptera was 9% higher in FRG varieties. Community composition changed with the proportion of SNH and differed between organic and conventional management. Overall, organic viticulture was not effective to enhance the arthropod community, which was dominated by flying insects in our study. Agricultural policies should therefore rather preserve and promote SNH in the surrounding in order to promote arthropod biodiversity in viticultural landscapes. [ABSTRACT FROM AUTHOR]

Background: Urban streams are characterised by species-poor and frequently disturbed communities. The recovery of heavily polluted urban streams is challenging but the simple community structure makes recolonisation patterns more transparent. Therefore, they are generally applicable model systems for recolonisation of restored streams. Principal questions of stream restoration concern the drivers and patterns of recolonisation processes. Rarely, recolonisation of restored streams is recorded for a sufficient time to observe patterns of habitat and community development in detail. Over 10 years, we monitored benthic habitat changes and macroinvertebrate communities of eight restored sites in an urban stream network that was formerly used as an open sewer and thus, almost uninhabitable for macroinvertebrates prior to restoration. We analysed changes in environmental variables and communities with a selection of multi-variate analyses and identified indicator species in successional stages. Results: Proportions of stony substrate and conductivity decreased over time since restoration, while the riparian vegetation cover increased along with the amount of sandy substrate. The communities fluctuated strongly after restoration but began to stabilise after around eight years. TITAN analysis identified 9 species, (e.g. the mayfly Cloeon dipterum and the beetle Agabus didymus), whose abundances decreased with time since restoration, and 19 species with an increasing abundance trend (e.g. several Trichopteran species, which colonised once specific habitats developed). Woody riparian vegetation cover and related variables were identified as major driver for changes in species abundance. In the last phase of the observation period, a dry episode resulted in complete dewatering of some sites. These temporarily dried sections were recolonised much more rapidly compared to the recolonisation following restoration. Conclusions: Our results underline that community changes following urban stream restoration are closely linked to the evolving environmental conditions of restored streams, in particular habitat availability initialised by riparian vegetation. It takes about a decade for the development of a rich and stable community. Even in streams that were almost completely lacking benthic invertebrates before restoration, the establishment of a diverse macroinvertebrate community is possible, underlining the potential for habitat restoration in formerly heavily polluted urban areas. [ABSTRACT FROM AUTHOR]

Species' range shifts and local extinctions caused by climate change lead to community composition changes. At large spatial scales, ecological barriers, such as biome boundaries, coastlines, and elevation, can influence a community's ability to shift in response to climate change. Yet, ecological barriers are rarely considered in climate change studies, potentially hindering predictions of biodiversity shifts. We used data from two consecutive European breeding bird atlases to calculate the geographic distance and direction between communities in the 1980s and their compositional best match in the 2010s and modeled their response to barriers. The ecological barriers affected both the distance and direction of bird community composition shifts, with coastlines and elevation having the strongest influence. Our results underscore the relevance of combining ecological barriers and community shift projections for identifying the forces hindering community adjustments under global change. Notably, due to (macro)ecological barriers, communities are not able to track their climatic niches, which may lead to drastic changes, and potential losses, in community compositions in the future. [ABSTRACT FROM AUTHOR]

Consumers play an integral role in mediating ecological succession—the change in community composition over time. As consumer populations are facing rapid decline in ecosystems around the world, understanding of their ecological role is becoming increasingly urgent. Increased understanding of how changes in consumer populations may influence community variability across space and turnover through time during succession is particularly important for coral reefs, which are among the most threatened ecosystems globally, and where fishes play vital roles in structuring benthic succession. Here, we examine how consumers influence coral reef succession by deploying 180 paired settlement tiles, caged (to exclude fishes larger than approximately 15 cm) and uncaged, within Palmyra Atoll, a remote marine wildlife refuge with previously documented high fish abundance, and monitored benthic community development one and three years after deployment. We found that excluding large fishes lead to lower alpha diversity and divergent community states across space (i.e.,, high beta diversity among caged tiles), suggesting that benthic fish feeding maintains local diversity but tends to homogenize community composition with dominance by crustose coralline algae. In addition, when fish were experimentally excluded, the developing benthic community exhibited a greater change in species composition over time (i.e., high temporal beta diversity), indicating that fish feeding tends to canalize community successional trajectories. Finally, the caged and uncaged tiles became more similar over time, suggesting that fish feeding plays a more important role during early succession. Our results demonstrate that the loss of large fishes, for example from overfishing, may result in benthic communities that are more variable across space and time. Increased variability could have important implications for ecosystem function and coral reef resilience in the face of escalating global stressors. [ABSTRACT FROM AUTHOR]

We studied β diversity of grasses in a subtropical grassland over 60 years in South Africa. We examined the effects of burning and mowing on 132 large plots. We sought to determine the effects of burning and mowing, and mowing frequency, on the replacement of species and the species richness. We conducted the study at Ukulinga, research farm of the University of KwaZulu‐Natal, Pietermaritzburg, South Africa (29°24′E, 30°24′S) from 1950–2010. Plots were burned annually, biennially, triennially, and a control (unburned). Plots were mowed in spring, late summer, spring plus late summer, and a control (unmowed). We calculated β diversity, with a focus on replacement and richness differences. We also used distance‐based redundancy analyses to examine the relative effects of replacement and richness differences on mowing and burning. We used beta regressions to test for the effect of soil depth and its interactions with mowing and burning. There was no significant change in grass beta diversity until 1995. Thereafter, there were changes in β diversity that demonstrated the primary effects of summer mowing frequency. There was no significant effect of richness differences but a strong effect of replacement post‐1995. There was a significant interaction between mowing frequency and soil depth in one of the analyses. Changes in grassland composition took a long time to manifest themselves and were unapparent prior to 1988. However, there was a change in sampling strategy prior to 1988, from point hits to nearest plants, that may also have influenced the rates of changes in replacement and richness differences. Using β‐diversity indices, we found that mowing was more important than burning that burning frequency was unimportant, and there was a significant interaction effect between mowing and soil depth in one of the analyses. [ABSTRACT FROM AUTHOR]