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Bacteria release metabolites into the surrounding environment, which can potentially be utilised by other bacteria. Current understanding of the limits of bacterial chemotaxis derived from the classic Escherichia coli model suggests that bacteria cannot use chemotaxis to detect targets smaller than a few micrometres in diameter, precluding the utility of chemotaxis in interactions between individual bacteria. Many bacteria exhibit chemotactic capacity that deviates from the classic E. coli model for chemotaxis, with some species displaying substantially heightened levels of chemotactic precision, potentially permitting chemosensing of small bacterial targets. There is recent evidence for a role for chemotaxis in metabolite exchange between small bacterial cells. Chemotactic sensing between bacteria could play a significant role in shaping interbacterial interactions. Chemotaxis allows microorganisms to direct movement in response to chemical stimuli. Bacteria use this behaviour to develop spatial associations with animals and plants, and even larger microbes. However, current theory suggests that constraints imposed by the limits of chemotactic sensory systems will prevent sensing of chemical gradients emanating from cells smaller than a few micrometres, precluding the utility of chemotaxis in interactions between individual bacteria. Yet, recent evidence has revealed surprising levels of bacterial chemotactic precision, as well as a role for chemotaxis in metabolite exchange between bacterial cells. If indeed widespread, chemotactic sensing between bacteria could represent an important, but largely overlooked, phenotype within interbacterial interactions, and play a significant role in shaping cooperative and competitive relationships. [ABSTRACT FROM AUTHOR]

• Braun-Blanquet procedures and juice software successfully used for data collection and analysis. • Two major communities consisting of three subcommunities and four variants were described. • High species richness and diversity is highlighted by 156 plant species recorded from 59 plots. • The research underscores the role of BSP in effectively managing and conserving threatened ecosystems. • The result of ecological index method indicates a moderate (49%) veld condition. • Valuable findings for comparing with broader vegetation patterns and classification. Privately owned properties declared as protected areas through Biodiversity Stewardship Programme (BSP) increase South Africa's priority biodiversity areas. The North-Eastern Cape grasslands, recognised as high biodiversity areas, are crucial for conserving the Grassland Biome. BSP plays a key role in effectively managing these vital vegetation types, securing and preserving threatened species. This study aimed to describe the vegetation and to determine the condition of Glencoe farm, located within the Eastern Cape Drakensberg Strategic Water Source Area and planning domain for the Eastern Cape Protected Area Expansion Strategy priority areas. The Braun-Blanquet method was employed to classify the plant communities. Two major communities consisting of three subcommunities and four variants were classified. Fifty-nine sample plots were surveyed and 156 plant species dominated by herbaceous species (137), and only 19 woody species were recorded. The area has high species diversity (Shannon Diversity Index: H' = 2.272) that is evenly distributed (E H = 0.987). The Ecological Index Method (EIM) results indicated a moderate veld condition score of 49%. The area is dominated by Increaser II species (52%) followed by Increaser I (16%) species. These findings have broader implications for stakeholders managing privately owned properties designated as protected areas through the BSP in South Africa. The North-Eastern Cape grasslands, recognized for their significant biodiversity, require safeguarding to preserve the Grassland Biome. Effective management of these critical vegetation types is essential for securing and conserving threatened ecosystems, thereby protecting South Africa's priority biodiversity areas. [ABSTRACT FROM AUTHOR]

[Display omitted] Structural information of grassland changes on the Tibetan Plateau is essential for understanding alterations in critical ecosystem functioning and their underlying drivers that may reflect environmental changes. However, such information at the regional scale is still lacking due to methodological limitations. Beyond remote sensing indicators only recognizing vegetation productivity, we utilized multivariate data fusion and deep learning to characterize formation-based plant community structure in alpine grasslands at the regional scale of the Tibetan Plateau for the first time and compared it with the earlier version of Vegetation Map of China for historical changes. Over the past 40 years, we revealed that (1) the proportion of alpine meadows in alpine grasslands increased from 50% to 69%, well-reflecting the warming and wetting trend; (2) dominances of Kobresia pygmaea and Stipa purpurea formations in alpine meadows and steppes were strengthened to 76% and 92%, respectively; (3) the climate factor mainly drove the distribution of Stipa purpurea formation, but not the recent distribution of Kobresia pygmaea formation that was likely shaped by human activities. Therefore, the underlying mechanisms of grassland changes over the past 40 years were considered to be formation dependent. Overall, the first exploration for structural information of plant community changes in this study not only provides a new perspective to understand drivers of grassland changes and their spatial heterogeneity at the regional scale of the Tibetan Plateau, but also innovates large-scale vegetation study paradigm. [ABSTRACT FROM AUTHOR]

Bacteroidetes can adapt to physicochemically and (micro)biologically diverse niches ranging from aquatic to terrestrial environments. Bacteroidetes actively participate in global nutrient cycling. Less attention has been given to Bacteroidetes in plant microbiomes compared to their counterparts associated with human and animal guts. By facilitating nutrient uptake and defense against various (a)biotic stress, Bacteroidetes significantly contribute to host fitness. Bacteroidetes' genomes harbor a rich repertoire of enzymes and biosynthetic gene clusters that allow versatile lifestyles. Bacteroidetes are prevalent in soil ecosystems and are associated with various eukaryotic hosts, including plants, animals, and humans. The ubiquity and diversity of Bacteroidetes exemplify their impressive versatility in niche adaptation and genomic plasticity. Over the past decade, a wealth of knowledge has been obtained on the metabolic functions of clinically relevant Bacteroidetes, but much less attention has been given to Bacteroidetes living in close association with plants. To improve our understanding of the functional roles of Bacteroidetes for plants and other hosts, we review the current knowledge of their taxonomy and ecology, in particular their roles in nutrient cycling and host fitness. We highlight their environmental distribution, stress resilience, genomic diversity, and functional importance in diverse ecosystems, including, but not limited to, plant-associated microbiomes. [ABSTRACT FROM AUTHOR]

Drought, which is increasing in intensity and frequency with climate change, can severely affect plant growth and alter vegetation dynamics. Plants modify microbial communities in their rhizosphere, which in turn affect plant productivity and local persistence, creating so-called plant–soil feedback (PSF). As droughts impact both plant and soil microbial attributes, PSF is likely to change under and following drought events, but limited experimental tests produce widely diverging results regarding the direction and magnitude of changes. Combined evidence from a range of related research fields suggests that PSF response to drought may be predicted by plant traits, the intensity of drought, and the drought histories of both plants and microbes. Explicit inclusion of coexistence history and the local adaptation of plants and soil microbes at local and regional scales will enable more realistic predictions about the contribution of plant–microbial associations to plant community response to climate change. Plant–soil feedback (PSF) is widely recognised as a driver of plant community composition, but understanding of its response to drought remains in its infancy. Here, we provide a conceptual framework for the role of drought in PSF, considering plant traits, drought severity, and historical precipitation over ecological and evolutionary timescales. Comparing experimental studies where plants and microbes do or do not share a drought history (through co-sourcing or conditioning), we hypothesise that plants and microbes with a shared drought history experience more positive PSF under subsequent drought. To reflect real-world responses to drought, future studies need to explicitly include plant–microbial co-occurrence and potential co-adaptation and consider the precipitation history experienced by both plants and microbes. [ABSTRACT FROM AUTHOR]

Contrary to their terrestrial counterparts, freshwater plants are linked to flooding dynamics associated with their habitats in or around water. Gas diffusivity, light availability, nutrient concentrations, and flow velocity select not only on freshwater eco-physiological adaptive traits but also on general plant functional traits, such as plant height or specific leaf area. Emerging stressors under global change impact freshwater plant functions at different temporal and spatial scales via both trait–trait and trait–environment relationships. Predicting how freshwater plant communities are changing and the reciprocal relationships between freshwater plant functions and the environment will require a focus on the specific conditions and traits important for a life in water. Freshwater ecosystems are of worldwide importance for maintaining biodiversity and sustaining the provision of a myriad of ecosystem services to modern societies. Plants, one of the most important components of these ecosystems, are key to water nutrient removal, carbon storage, and food provision. Understanding how the functional connection between freshwater plants and ecosystems is affected by global change will be key to our ability to predict future changes in freshwater systems. Here, we synthesize global plant responses, adaptations, and feedbacks to present-day and future freshwater environments through trait-based approaches, from single individuals to entire communities. We outline the transdisciplinary knowledge benchmarks needed to further understand freshwater plant biodiversity and the fundamental services they provide. [ABSTRACT FROM AUTHOR]

Harnessing natural genetic variation is an established alternative to artificial genetic variation for investigating the molecular dialog between partners in plant pathosystems. Herein, we review the successes of genome-wide association studies (GWAS) in both plants and pathogens. While GWAS in plants confirmed that the genetic architecture of disease resistance is polygenic, dynamic during the infection kinetics, and dependent on the environment, GWAS shortened the time of identification of quantitative trait loci (QTLs) and revealed both complex epistatic networks and a genetic architecture dependent upon the geographical scale. A similar picture emerges from the few GWAS in pathogens. In addition, the ever-increasing number of functionally validated QTLs has revealed new molecular plant defense mechanisms and pathogenicity determinants. Finally, we propose recommendations to better decode the disease triangle. The increase in the number and severity of plant diseases due to global changes calls for a better understanding of the molecular mechanisms underlying natural genetic variation in both plant immunity and pathogen aggressiveness. Our meta-analysis of genome-wide association (GWA) studies (GWAS) in plant pathosystems highlights the power of GWA mapping to characterize thoroughly the genetic architecture of plant responses to a wide range of pathogens, subsequently leading to the identification of novel defense mechanisms. GWAS in pathogens revealed fewer, but nonetheless important, successes, which during the past decade allowed us to take a small step forward in deciphering new pathogenic genetic determinants. Setting up co-GWAS in ecologically realistic conditions will help to develop increasingly robust and ecofriendly strategies to control plant pathogens. [ABSTRACT FROM AUTHOR]

The metamicrobiome is an integrated concept to study carbon and nutrient recycling in ecosystems. Decomposition of plant-derived matter by free-living microbes and fire – two key recycling pathways – are highly sensitive to global change. Mutualistic associations of microbes with plants and animals strongly reduce this sensitivity. By solving a fundamental allometric trade-off between metabolic and homeostatic capacity, these mutualisms enable continued recycling of plant matter where and when conditions are unfavourable for the free-living microbiome. A diverse metamicrobiome – where multiple plant- and animal-associated microbiomes complement the free-living microbiome – thus enhances homeostasis of ecosystem recycling rates in variable environments. Research into metamicrobiome structure and functioning in ecosystems is therefore important for progress towards understanding environmental change. Carbon and nutrient transformations by free-living microbes and fire in terrestrial ecosystems are highly sensitive to climatic variability, causing concerns about the responses of ecosystems to the current accelerated rates of environmental change. Metamicrobiome ecology synthesises different aspects of plant matter recycling pathways by intimately interacting microbiomes, emphasising the global role of three main mutualistic microbiomes in addition to free-living microbiomes. Microbes have higher metabolic capacity, while multicellular organisms have higher homeostatic capacity. The mutualistic associations between small and large organisms, therefore, increase their joint metabolic rates, also under unfavourable environmental conditions. Replacing this trade-off with a synergy becomes increasingly important under more stressful conditions, altering expected ecosystem responses to environmental change. [ABSTRACT FROM AUTHOR]

Interactions among plants have been long recognized as a major force driving plant community dynamics and crop yield. Surprisingly, our knowledge of the ecological genetics associated with variation of plant–plant interactions remains limited. In this opinion article by scientists from complementary disciplines, the international PLANTCOM network identified four timely questions to foster a better understanding of the mechanisms mediating plant assemblages. We propose that by identifying the key relationships among phenotypic traits involved in plant–plant interactions and the underlying adaptive genetic and molecular pathways, while considering environmental fluctuations at diverse spatial and time scales, we can improve predictions of genotype-by-genotype-by-environment interactions and modeling of productive and stable plant assemblages in wild habitats and crop fields. A better understanding of plant community diversity, productivity, and stability relies on deciphering the ecological genetics and molecular bases of plant–plant interactions in wild and crop species, which range from competitive to positive interactions. Compared with other categories of biotic interactions, we have limited knowledge of the genetics associated with natural variation of plant–plant interactions. Interdisciplinary projects are needed to explore the genetic and molecular underpinnings of key interacting phenotypic traits involved in plant–plant interactions, at complementary observation scales in a complex biotic and abiotic environment. Our future knowledge on the genetics of plant–plant interactions can fuel models aimed at predicting the best performing and/or stable plant assemblages, leading to alternative and eco-friendly agricultural systems. [ABSTRACT FROM AUTHOR]

With the rapid accumulation of plant trait data, major opportunities have arisen for the integration of these data into predicting ecosystem primary productivity across a range of spatial extents. Traditionally, traits have been used to explain physiological productivity at cell, organ, or plant scales, but scaling up to the ecosystem scale has remained challenging. Here, we show the need to combine measures of community-level traits and environmental factors to predict ecosystem productivity at landscape or biogeographic scales. We show how theory can extend the production ecology equation to enormous potential for integrating traits into ecological models that estimate productivity-related ecosystem functions across ecological scales and to anticipate the response of terrestrial ecosystems to global change. The integration of plant functional traits to improve predictions of ecosystem productivity holds many opportunities, especially considering that intrinsic links are expected between plant traits and ecosystem function. We present a novel framework for 'trait-based productivity' (TBP) enabling the prediction of productivity-related ecosystem functions from plant community traits and environmental conditions. The TBP framework takes an emergent perspective considering the ecosystem as a whole, in which individual plant traits scale up to community-scale 'traits' that in combination influence ecosystem functions. The TBP framework has potential to drive a new generation of ecological models at a wide range of spatial scales, informed by species' traits derived from open access trait databases and high-resolution remote sensing imagery data. [ABSTRACT FROM AUTHOR]

Soil microbiota plays a fundamental role in nutrient cycles and plant fitness. However, the response of bacterial and fungal communities interacting with plants to an increase in the water regime in natural ecosystems has yet to be extensively studied. To address this matter, we studied the response of rhizospheric and root endophytic microbial communities to simulated intense precipitation in a natural desert environment. We used amplicon sequencing to identify bacterial (16S) and fungal (ITS) communities of Haloxylon salicornicum (Moq) Bunge ex Boiss., a pivotal plant species in natural ecosystems with a high potential for land restauration. Bacterial community composition included mostly Actinobacteriota in roots and Chloroflexi in rhizospheres, whereas fungal communities were mostly represented by Ascomycota. The decomposition of beta diversity revealed a significant share of i) turnover for bacteria between compartments, ii) nestedness for fungi according to compartments, and iii) nestedness for bacteria in both rhizosphere and roots according to watering. Differential abundances analyses between watering conditions identified respectively i) 29 and 37 differentially abundant bacterial families, and ii) 7 and 6 differentially abundant fungal families for rhizosphere and roots. Watering induced a rapid response from little characterized microbiota potentially involved in nutrient recycling, such as rhizobia and dark septate endophytes. These results provided evidence of the fundamental role of rare and intense precipitation in modifying the microbial composition of roots and rhizosphere of one desert plant species. Moreover, little studied taxa potentially crucial to the plant health in desert environments such as dark septate endophytes and Planctomycetota were identified as pioneer taxa colonizing freshly emitted roots. Collectively, our results help to improve the understanding of desert taxa response to water availability, and may guide future research on natural ecosystems restauration. [Display omitted] • Desert ecosystems are subjected to high water stress, limiting plant growth. • Drought increases the abundance of drought-tolerant Actinobacteria and Acidobacteria. • Microbiota of Haloxylon salicornicum roots and rhizosphere is responsive to water. • Symbionts taxa are differentially expressed following watering. • Little studied dark septate endophytes may be important plant symbiont. [ABSTRACT FROM AUTHOR]

The extent to which soil bioengineering preserves the ecological functions of riverbank vegetation beyond erosion control remains largely unexplored. This study compared the functional response of plant communities on soil-bioengineered riverbanks with those on natural and hard-engineered (ripraps) riverbanks across 124 sites in Quebec, Canada. We hypothesized that the Community Weighted Means (CWM) of 10 functional traits and three ecological attributes relevant in a riparian context and based on 356 plant taxa would be similar between bioengineered and natural sites, while functional diversity measured as richness (FRic) and dispersion (FDis) would be higher in bioengineered sites due to the diverse conditions (substrate, microhabitats). Contrary to expectations, we found trait-specific results. Compared to ripraps, natural sites were dominated by plants that were taller and had lighter seeds, as well as higher dispersion in specific leaf area, height, and seed mass, higher FRic, more dispersion of propagules by water and less by animals, and more plants with vegetative reproduction, shade tolerance, wetland-affinity, native, and fewer ruderal species. Bioengineered sites had intermediate mean trait values and dispersion, and only small differences among the three techniques applied (pure, keyed, and mixed) regarding the proportion of living and mineral material. Consistent with a previous study that used the same set of sites, we found higher plant cover, species richness, and diversity in natural sites compared to ripraps, with bioengineered sites falling in between the two. Bioengineering can partially reproduce natural riparian plant communities both taxonomically and functionally. Practitioners should consider functional diversity in their designs. • Bioengineering may partially restore functionality of riverbank plant communities. • Functional response of riparian vegetation to soil stabilization is trait-specific. • Riverbank stabilization should consider trait diversity as well as species identity. [ABSTRACT FROM AUTHOR]

The spread of livestock manure-borne antibiotic resistance genes (ARGs) into agroecosystems through manure application poses a potential threat to human health. However, there is still a knowledge gap concerning ARG dissemination in coalescing manure, soil and plant microbiomes. Here, we examined the fate of tetracycline resistance genes (TRGs) originating from pig manure microbiomes and spread in the soil- A thaliana system and explored the effects of microbial functions on TRGs spread at different interfaces. Our results indicate that the TRGs abundances in all microbiome continuum of the soil- A. thaliana system were significantly increased with the application of a living manure microbiome, although the addition of manure with both an active and inactive microbiome caused a shift in the microbial community composition. This was attributed to the increasing relative abundances of tet A, tet L, tet M, tetO, tet W and tol C in the system. The application of living manure with DOX residues resulted in the highest relative abundance of total TRGs (3.30×10−3 copies/16S rRNA gene copies) in the rhizosphere soil samples. Community coalescence of the manure and soil microbiomes increased the abundance of Firmicutes in the soil and root microbiome, which directly explains the increase in TRG abundance observed in these interfaces. In contrast, the leaf microbiome differed markedly from that of the remaining samples, indicating strong plant host filtering effects on Firmicutes and TRGs from pig manure. The random forest machine learning model revealed microbial functions and their significant positive correlation with TRG abundance in the microbiome continuum of the system. Our findings revealed that community coalescence is the main driver of TRG spread from manure to the soil and root microbiomes. Plant host filtering effects play a crucial role in allowing certain microbial groups to occupy ecological niches in the leaves, thereby limiting the establishment of manure-borne TRGs in aboveground plant tissues. [Display omitted] [ABSTRACT FROM AUTHOR]

Arctic tundra ecosystems store a significant proportion of the global soil organic carbon (C). However, warming-induced shrub encroachment and reindeer (Rangifer tarandus L.) grazing regimes promoting graminoid vegetation may strongly influence tundra soil C stability. Here, we studied how reindeer grazing intensity and experimental warming affect soil C stabilization in a tundra ecosystem. We hypothesized that under light grazing, persistent complexes formed by fungal necromass (FNM) and condensed tannins (CT) from shrub roots stabilize the soil C, whereas, under heavy grazing, the soil C stabilization is affected by glomalin-related soil proteins (GRSP) produced by arbuscular mycorrhizal fungi of graminoids. In addition, we expect warming to mediate grazing effects, diminishing the potential for C stabilization. Our results show no effect of grazing on stable C concentration, however, under light grazing the labile C concentration was higher. We found higher concentrations of chitin and tannins under light grazing, indicative of soil C stabilization potential through FNM-CT complexes. By contrast, we found more root ergosterol under heavy grazing, suggesting a high abundance of endophytes, usually melanized, and a slightly higher GRSP concentration. Warming did not cause changes in stable C concentration but was associated with changes in the soil chemical quality, pointing to a decrease of lignin, polypeptides, and polysaccharides. We conclude that different soil C stabilization mechanisms operate under light and heavy grazing pressures and that these mechanisms are closely linked to changes in the vegetation and the fungi typically associated with them. • Different C stabilization mechanisms operate under light and heavy grazing pressures. • Under light grazing C stabilization is dependent on root-fungal necromass interaction. • Under heavy grazing C stabilization is linked to endophytic and arbuscular fungi. • Overall, soil stable C concentration was not changed by grazing intensity or warming. [ABSTRACT FROM AUTHOR]

The fine-scale spatial heterogeneity of low-growth Arctic tundra landscapes necessitates the use of high-spatial-resolution remote sensing data for accurate detection of vegetation patterns. While multispectral satellite and aerial imaging, including the use of uncrewed aerial vehicles (UAVs), are common approaches, hyperspectral UAV imaging has not been thoroughly explored in these ecosystems. Here, we assess the added value of hyperspectral UAV imaging relative to multispectral UAV imaging in modelling plant communities in low-growth oroarctic tundra heaths in Saariselkä, northern Finland. We compare three different spectral compositions: 4-channel broadband aerial images, 5-channel broadband UAV images and 112-channel narrowband UAV images. Based on field vegetation plot data, we estimate vascular plant aboveground biomass, leaf area index, species richness, Shannon's diversity index, and community composition. We use spectral and topographic information to compile 12 explanatory datasets for random forest regression and classification. For aboveground biomass and leaf area index, the highest R2 values were 0.60 and 0.65, respectively, and broadband variables were most important. In the best models for biodiversity metrics species richness and Shannon's index R2 values were 0.53 and 0.46, respectively, with hyperspectral, topographic, and multispectral variables having high importance. For 4 floristically determined community clusters, both random forest classifications and fuzzy cluster membership regressions were conducted. Overall accuracy (OA) for classification was 0.67 at best, while cluster membership was estimated with an R2 of 0.29–0.53. Variable importance was heavily dependent on community composition, but topographic, multispectral, and hyperspectral data were all selected for these community composition models. Hyperspectral models generally outperformed multispectral ones when topographic data were excluded. With topographic data, this difference was diminished, and performance improvements from added hyperspectral data were limited to 0–10 percentage point increases in R2, the largest occurring in the metrics with lowest R2. These results suggest that while hyperspectral can outperform multispectral imaging, multispectral and topographic data are mostly sufficient in practical applications in tundra heaths. [Display omitted] • Tundra plant community composition, productivity and diversity were mapped with UAVs. • Multispectral greenness indices were key to estimating biomass and LAI. • Hyperspectral data improved community composition estimation by 2–10 pp. • Topographic data compensated spectral data in estimating composition and diversity. [ABSTRACT FROM AUTHOR]

Nitrogen (N) and phosphorus (P) enrichments are expected to increase above-ground net primary productivity (ANPP), alter plant community composition, and accelerate biodiversity losses. However, how N and P synergistically affect plant communities and the underlying mechanisms remain elusive. Here, a 2-year in situ experiment with five levels of N and two levels of P treatments in an arid ecosystem was conducted to examine the independent and interactive effects of N and P additions on plant community structure and ANPP and their driving factors. The analysis of variance showed that nutrient enrichment significantly increased ANPP by a maximum value of 93% at N (15 g N m−2 yr−1) treatment and a maximum of 95% at N-P (10 g N m−2 yr−1, 10 g P 2 O 5 m−2 yr−1) treatments. N addition alone significantly decreased species richness and dominance but increased evenness and diversity. The principal component analysis indicated that dominant species of plant communities gradually shifted from a perennial species Stipa breviflora to an annual species Tribulus terrestris under N and P enrichments. The nonmetric multi-dimensional scaling ordination revealed that N addition significantly promoted the divergence in species composition, whereas P enrichment relieved this change. The structural equation modelling illustrated that N and P additions affected ANPP mainly via modifying plant community composition and structure. This study demonstrates that the potential mechanism of adverse changes in a vulnerable ecosystem is related to the alterations in plant functional groups mainly due to divergent responses of dominant species to nutrient enrichment. This should be considered when assessing and modelling the ecological and evolutionary trajectories of terrestrial ecosystems under the conditions of global environmental changes. [Display omitted] • A N enrichment gradient with P addition was designed in an arid ecosystem. • Significant effects of N and P addition alone on plant community were observed. • ANPP and species diversity were predominated by a few critical species. • PFG under nutrient enrichment shifted from perennial grass to annual forb species. • N addition accelerated the divergence in plant community composition. [ABSTRACT FROM AUTHOR]

• Community 'cohesion' index increased by 54.45% under light grazing compared to heavy grazing. • Identify the indicate plant species of each grazing intensity treatment with the SPEC-OCCU plot. • Plant factors mainly affect the plant community stability under light gazing practice. • Soil factors regulate the plant community stability under light gazing practice. On the Tibetan Plateau, most alpine meadows have undergone various degree of degradation due to heavy grazing practices. Assessing the progress of grazing succession, identify the indicator species for different grazing managements is crucial to facilitate the effective restoration of degraded alpine meadows. In this study, specific areas with varying levels of grazing intensity were selected to assess the stability of plant communities, to identify the indicator species for each stage, and to examine the driving factors influencing community stability. The results showed that (i) plant community stability was found to be highest under light and moderate levels of grazing. In comparison to heavy grazing treatment, the community "cohesion" index (|Negative cohesion|) increased by 54.45% under light grazing treatment and by 23.24% under moderate grazing treatment. (ii) the indicator species varied across different succession stages and played distinct roles. Dominant species were identified as indicator species with no grazing and light grazing treatment, whereas rare poisonous species served as indicators under heavy grazing treatment. (iii) the driving factors and mechanisms influencing community stability differed throughout gradient of grazing intensity. Plant-related factors primarily influenced community stability under light grazing, while soil-related factors began to play a joint role under heavy grazing. This empirical knowledge contributes to establishing a scientific basis for the rational utilization and management of alpine meadow ecosystems. [ABSTRACT FROM AUTHOR]

We used a combined approach (lithofacies and palynology) and multivariate analyses to reconstruct the different depositional environments and changes in the plant communities throughout the middle to late Kungurian in the tropical Pangea. The late Paleozoic terrestrial biotas underwent changes under the pressure of a general aridification trend and a warming event that changed biota composition favoring drought-tolerant taxa during the Artinskian. Few studies integrate the different terrestrial ecosystem components to reconstruct palaeoenvironments and climate changes throughout the Cisuralian (early Permian). We analyzed several sedimentary successions of different stratigraphic positions intercalated in well-dated volcanic units of the megacaldera of the Athesian Volcanic Group (Southern Alps, northern Italy). The obtained palynofacies and quantitative sporomorph records with an exceptional high resolution (∼ 10 Ma) evidence a palaeoenvironmental/climatic change in the plant communities from the middle to the late Kungurian. The late Kungurian shows a higher diversity in the plant communities with a dominance of seed ferns and a higher relative abundance of xeromorphic-hygromorphic sporomorph taxa. This suggests the presences of more stable and putatively more humid environmental conditions in respect to the middle Kungurian. Furthermore, a direct comparison between lithofacies and all primary components of the palynofacies assemblages permits to characterize lacustrine and alluvial depositional environments since these studies are underrepresented for terrestrial environments. • Environments in a Kungurian megacaldera are studied by palynology and lithofacies. • High resolution data reveal middle to late Kungurian palaeoenvironmental changes. • The late Kungurian displays a stable environment and a diverse plant community. • The observed changes could reflect the change in intensity of the volcanic activity. [ABSTRACT FROM AUTHOR]

Long-term ecosystem development is characterized by a switch from nitrogen (N) to phosphorus (P) limitation of plant communities as soils age, which leads to changes in plant biomass, diversity, and foliar nutrient concentrations. Similar effects occur belowground, although the extent to which nutrient availability is the primary driver of long-term changes in soil microbial communities remains uncertain. To investigate this, we assessed proxies for soil microbial nutrient limitation along the Jurien Bay dune chronosequence in Western Australia, where a long-term decline in P availability is reflected in strong variation in plant and microbial community composition over 2 million years of soil development. We quantified carbon (C), N, and P in the soil microbial biomass, assayed soil enzymes involved in the acquisition of those nutrients from soil organic matter, and used microbial stoichiometric ratios and vector analysis of enzyme activities to assess whether long-term changes in soil nutrient availability are reflected in nutrient demand by soil microbes. Concentrations of microbial nutrients peaked in Holocene soils (1–6.5 ky), although differences in microbial P were not significant. There were no significant differences in microbial nutrient ratios (C:N, C:P, and N:P) along the chronosequence. Acid phosphatase activity increased continually throughout the chronosequence, while the activities of leucine aminopeptidase and β-glucosidase were greatest in Holocene soils and declined with increasing soil age. Corresponding vector lengths indicated greater investment in C-degrading enzymes in Holocene soils (≤6.5 ky), while vector angles indicated greater investment in the acquisition of P compared with N in Pleistocene soils (≥120 ky). Overall, these findings show that changes in nutrient availability during long-term pedogenesis at Jurien Bay are reflected in microbial investment in nutrient acquisition, but that the soil microbial biomass exhibits a remarkable degree of homeostasis despite major shifts in nutrient availability and community composition over 2 million years of ecosystem development. • Soil enzyme activities and microbial biomass over 2 million years of ecosystem development. • Enzymes indicates carbon and nitrogen limitation on young soils and P limitation on old soils. • Maximum microbial biomass in intermediate-aged soils. • Microbial stoichiometry unchanged along the chronosequence. [ABSTRACT FROM AUTHOR]

The phyllosphere, particularly the leaf surface of plants, harbors a diverse range of microbiomes that play a vital role in the functioning of terrestrial ecosystems. However, our understanding of microbial successions and their impact on functional genes during plant community development is limited. In this study, considering core and satellite microbial taxa, we characterized the phyllosphere microbiome and functional genes in various microhabitats (i.e., leaf litter, moss and plant leaves) across the succession of a plant community in a low-altitude glacier foreland. Our findings indicate that phyllosphere microbiomes and associated ecosystem stability increase during the succession of the plant community. The abundance of core taxa increased with plant community succession and was primarily governed by deterministic processes. In contrast, satellite taxa abundance decreased during plant community succession and was mainly governed by stochastic processes. The abundance of microbial functional genes (such as C, N, and P hydrolysis and fixation) in plant leaves generally increased during the plant community succession. However, in leaf litter and moss leaves, only a subset of functional genes (e.g., C fixation and degradation, and P mineralization) showed a tendency to increase with plant community succession. Ultimately, the community of both core and satellite taxa collaboratively influenced the characteristics of phyllosphere nutrient-cycling genes, leading to the diverse profiles and fluctuating abundance of various functional genes during plant community succession. These findings offer valuable insights into the phyllosphere microbiome and plant–microbe interactions during plant community development, advancing our understanding of the succession and functional significance of the phyllosphere microbial community. [ABSTRACT FROM AUTHOR]

Microbial communities on plant surfaces are crucial in regulating plant growth and disease control. Exploring the composition of microorganisms on plant surfaces is essential for understanding their potential functions. The restructuring of microbial communities can help reduce postharvest diseases and maintain fruit quality. In this study, the use of Bacillus velezensis LX fermentation broth resulted in a reduction of Diaporthe and Fusarium abundance on the surface of kiwifruit, as well as changed in the fungal and bacterial communities on the kiwifruit surface, as determined by high-throughput sequencing. B.velezensis LX treatment reduces the natural decay incidence of postharvest kiwifruit but does not decrease the quality of kiwifruit. An analysis of the relationship between microbial taxa and fruit decay incidence revealed that several genera, including Plectosphaerella , Vishniacozyma , Cryptococcus , Papiliotrema , Aureobasidium , Filobasidium , Actinomycetospora , and Parasutterella , were enriched in the CK and LX treatment group during storage. This study contributes to a better understanding of how microbial antagonists regulate postharvest diseases in kiwifruit and provides insights for establishing a beneficial microbial synthetic flora to enhance the postharvest safety of kiwifruit. • Bacillus velezensis LX can inhibit the growth of kiwifruit postharvest pathogens. • Bacillus velezensis LX reduces the natural decay incidence of kiwifruit. • Bacillus velezensis LX alters the microbial structure on the surface of kiwifruit. • This study found several potentially beneficial genera for kiwifruit storage. [ABSTRACT FROM AUTHOR]

Growth of solar in India has been remarkable, with the installed capacity crossing the 50 GW mark. However, most of the assets are in utility format, with negligible share of decentralized plants. Centralized projects are preferred due to their competitive generation cost, or LCOE. Our study compares a centralized solar project with a decentralized plant on economic, social and technical aspects. Economic assessment reflects competitive cost of energy near to the point of consumption (landed cost) for both these plant types after accounting for transmission losses and associated charges. On technical aspects, we discovered a shifting solar curve, as the plant locations move from east to west of the country, thus providing an enlarged window of solar power generation. Utility scale projects preclude participation of smaller entities and leads to asset concentration. In contrast, decentralized plants promote community participation, generate higher employment, while enabling energy access for the local community. A balanced policy approach needs to be followed, promoting both types of project configurations. We propose setting up spatially dispersed solar plants along the longitudinal stretch of India, co-located within the substations using standardized templates. This shall enable fulfilment of climate goals, while ushering in a just transition. [ABSTRACT FROM AUTHOR]

Plants may effectively tailor defenses by recognizing their attackers and reprogramming their physiology. Although most plants are under attack by a large diversity of herbivores, surprisingly little is known about the physiological capabilities of plants to deal with attack by multiple herbivores. Studies on dual herbivore attack identified that defense against one attacker may cause energetic and physiological constraints to deal with a second attacker. How these constraints shape plant plasticity in defense to their full community of attackers is a major knowledge gap in plant science. Here, we provide a framework for plant defense to multiherbivore attack by defining the repertoire of plastic defense strategies that may allow plants to optimize their defenses against a multitude of stressors. Virtually all plants are under attack by a species-rich community of antagonists. A response to one attacker should be balanced with the costs that this response may entail toward defense against other attackers. Reprogramming of plant physiology to counteract herbivory is typically studied under single or dual attack. Often these studies identify antagonistic interactions that limit plants in their ability to resist a second attacker. The emerging physiological concepts may lead to a mismatch with the adaptive nature of plant responses in community context. Identifying plants' plasticity to deal with their full community of attackers is key in understanding plant defense strategies and requires unified terminology to illustrate the repertoire of plant plasticity matching ecological patterns of attack. [ABSTRACT FROM AUTHOR]

Here we present charcoal identifications for Rose Cottage Cave, Eastern Free State, from layers dated between about 96,000 and 35,000 years ago (~96 and ~35 ka ago). We then suggest plant community types that might have been established in the area in warm Marine Isotope Stage 5 (MIS5) versus cooler MIS4/MIS3 phases. The hypothesis is that frost-tender plants should occur in warm phases while hardy Leucosidea sericea , Protea spp. and Erica spp. should be more common during cooler phases more recent than ~74 ka ago. Leucosidea sericea thrives under moist conditions and its presence in late MIS4 and in several MIS3 layers at Rose Cottage implies that the area may have been moister than many other sites in the interior of southern Africa, thereby making it attractive for occupation. The charcoal identifications at ~96 ka ago included taxa like Buddleja salvifolia that need somewhat warmer conditions than taxa such as Leucosidea sericea. Taxa diversity based on the charcoal identifications is generally low at the site throughout the Middle Stone Age, but the vegetation from relatively warm MIS5 seems more diverse than that of MIS4 and MIS3. Some taxa identified, for example, Calodendrum capense , Leucosidea sericea , Erica caffra and Protea caffra no longer grow near the cave although they are commonly found in other parts of eastern South Africa. [ABSTRACT FROM AUTHOR]

[Display omitted] • The plant microbiota is associated with all plant organs, influencing many functions. • The composition of the plant microbiota depends on abiotic and biotic factors. • Local and global censuses reveal the dominance of few key taxa. • Bacterial and fungal communities modulate plant immunity, nutrition and development. • Engineering the plant microbiota may help in sustainable agriculture. Plants growing in nature live in association with beneficial, commensal, and pathogenic microbes, which make up the plant microbiota. The close interaction between plants and their microbiotas has raised fundamental questions about plant responses to these microbes and the identity of the main factors driving microbiota structure, diversity, and function in bulk soil, in the rhizosphere, and in the plant organs. Beneficial microorganisms have long been used as inoculants for crops; the current development of synthetic microbial communities and the identification of plant traits that respond to the microbiota form the basis for rational engineering of the plant microbiota to improve sustainable agriculture. [ABSTRACT FROM AUTHOR]

• The plant diversity and composition of the traditional agroecosystems of arid southern Morocco corresponds to the agricultural practice and the associated habitat conditions. • Traditional agroecosystems promote a high level of plant species and community diversity, both at the field and landscape levels. • The plant communities of traditional arid agroecosystems are dominated by indigenous species and host a number of regional and national endemic species, as well as some rare and endangered species. • The studied arable plant communities in the Mediterranean-Saharan transition zone in southern Morocco represent the southernmost occurrences of Mediterranean-type agroecosystems known so far. In the arid landscapes of South Morocco's Saharan fringe, traditional agroecosystems stand out for their rich diversity of segetal vegetation. This study examines the segetal flora of these unique agroecosystems, investigating their richness, community characteristics and composition. We collected 155 relevés in fields located in the Guelmim province comprising three agroecosystem types: Oases, terraced and floodplain fields (faïd). We found 221 vascular plant species including seven regional endemics and one nationally very rare species. Using TWINSPAN, we identified three plant communities, each restricted to a specific agroecosystem type, displaying differences in species composition, floristic status, life-form and biogeographical spectra. Oasis vegetation had the highest overall number of species, terraced fields had the highest diversity, and therophytes were dominant across all communities, with faïds being the most therophyte-rich. The pan-Mediterranean chorotype dominated all three community types. Apophytes dominated, particularly in faïd and terraced fields, surpassing oasis fields rich in ruderals. We found that traditional cereal agroecosystems in southern Morocco harbor species-rich segetal plant communities created by habitat-based land-use systems. Our results highlight the significance of agricultural practices and local abiotic factors in shaping the agroecosystems, which are adapted to arid environments and sensitive to environmental and social changes. [ABSTRACT FROM AUTHOR]

Plant community productivity is a major expression of grassland ecosystem services and functions. In the background of intensified atmospheric nitrogen deposition, studies on the productivity of semiarid sandy grassland with fragile ecological environments have mainly focused on the short-term effects of nitrogen addition, and most of them had concentrated on the aboveground, with relatively few studies on the belowground. In this study, we conducted long-term (from 2014 to 2022) experiment of nitrogen addition (10 g N m−2 year−1) and litter manipulation (litter removal(C1), litter doubling(C2) on sandy grassland in northern China, and measured plant community composition and productivity in 2022 to provide a scientific basis for plant restoration and management of semiarid sandy grasslands. The results were found: (1) Nitrogen addition significantly increased plant community height, coverage, aboveground biomass and total biomass, while litter removal significantly reduced plant coverage by 32.61% (P < 0.01) and significantly decreased the aboveground biomass of grasses by 40.24% (P < 0.05). (2) Nitrogen addition and aboveground litter had no significant effect on belowground biomass at different soil depths and belowground biomass. (3) Grasses were the main contributors to the productivity of plant communities in semiarid sandy grasslands. The belowground biomass was mainly concentrated in the 0–10 cm soil depth, and its proportion was 54% ∼ 78%. (4) The structural equation model showed that nutrient addition indirectly affected the total biomass through a significantly positive effect on soil nitrate nitrogen, dissolved organic carbon and community height. Litter manipulation indirectly affected the total biomass through a significantly negative effect on nitrate nitrogen. Overall, in sandy grassland, long-time litter removal can reduce the aboveground productivity of dominant functional group grasses, while appropriate nitrogen addition management can help to improve the productivity of grassland and promote its recovery and sustainability. Our findings highlight the importance of soil environmental characteristics and plant community characteristics in driving the long-term response of sandy grassland ecosystem productivity to climate change. • Nitrogen addition significantly increased the aboveground biomass and total biomass, while litter removal significantly decreased the aboveground biomass of grasses. • Nitrogen addition and aboveground litter had no significant effect on underground biomass at different soil depths and belowground biomass. • Grasses were the main contributors to the productivity of plant communities in semiarid sandy grasslands. • Nitrogen addition could directly affect the total biomass, and indirectly affected the total biomass through significant positive effects on soil nitrate nitrogen, dissolved organic nitrogen and community height. • Litter manipulation indirectly affected the total biomass through significantly negative effect on nitrate nitrogen. [ABSTRACT FROM AUTHOR]

• The geographic pattern of β-diversity across the three dimensions is highly consistent. • Taxonomic β-diversity is dominated by turnover components, whereas phylogenetic and functional β-diversity is dominated by nestedness components. • Environmental filtering and dispersal limitation together determine the geographic patterns of wetland plant β-diversity. • Climatic and topographic variables were the main drivers of the β-diversity pattern of wetland plants in the Qinghai-Tibet Plateau. The Qinghai-Tibet Plateau (QTP) harbours the largest wetland complex in China, with a relatively high diversity of wetland plants. While there has been extensive research on the α-diversity of various plant groups in the QTP, the study of β-diversity specifically in wetland plants has been limited. In this study, we quantified the geographic pattern of wetland plant β-diversity from three dimensions: taxonomic, phylogenetic, and functional. We assessed the relative importance of geographic distance, climatic distance, environmental distance and topographic distance on the pattern of β-diversity. The results indicate a high consistency in the geographic pattern of wetland plant β-diversity across the three dimensions. β-diversity is high in the mountainous regions at the edge of the plateau and relatively low in the plateau platform. The turnover component contributes more to taxonomic β-diversity than nestedness, whereas the opposite is true for phylogenetic and functional β-diversity. Furthermore, taxonomic β-diversity is higher than phylogenetic and functional β-diversity. The geographic patterns of taxonomic, phylogenetic and functional diversity of wetland plants in the QTP are jointly influenced by environmental filtering and dispersal limitation. Climatic variables (temperature seasonality, annual precipitation, precipitation seasonality and annual mean temperature) and topographic variables (elevation variation coefficient, elevation and slope) were identified as the main factors influencing wetland plant β-diversity in the QTP. Overall, this study contributes to elucidating the evolutionary history and formation mechanisms of wetland plant communities in the QTP, and reveals the large-scale patterns of wetland plant diversity. [ABSTRACT FROM AUTHOR]

• The root: shoot (R/S) increases from humid, semi-arid, to arid environments. • Soil dominates R/S change in alpine humid grassland. • Climate dominates R/S change in humid grassland. • Climate and plant mediate R/S change in semi-arid and arid grasslands. A variable future climate would lead to changes in the biomass allocation pattern of plant communities, but its divergent changes under different environments have not been clearly explored, greatly limiting a better understanding of the responsess of grassland ecosystems to environmental changes. Herein, we conducted field samplings at 215 grassland sites in the Qinghai-Tibetan and Inner Mongolian Plateaus to analyze community biomass allocation patterns (specifically, the ratio of root to shoot, R/S) in various grasslands along environmental gradients. We found a gradual increase in R/S from humid to semi-arid and arid environments across both plateaus. In humid environment, soil factor had a significant effect on the R/S of alpine humid grassland, while climate factor had a significant effect on the R/S of humid grassland. In semi-arid environment, both climate and plant factors had significant effects on R/S in semi-arid grassland. In arid environments, climate and plant factors had significant effects on R/S in arid grassland. These findings emphasize the multifaceted role of environmental factors in shaping biomass allocations across diverse ecosystems, enriching our understanding of ecological dynamics. The current results are timely in advancing the fundamental understanding of the mechanisms of biomass allocation in grasslands and are useful for global research on grasslands in different environments. [ABSTRACT FROM AUTHOR]

Salinity stress severely limits crop production globally. The plant rhizosphere harbors diverse microbial communities that can positively influence plant growth and stress tolerance. Therefore, we examined the rhizosphere bacterial populations of Brassica napus under normal and saline conditions using high-throughput 16S rRNA gene sequencing. The objectives were set to identify key taxa enriched in the rhizosphere and evaluate variations in community structure between control and salt-stressed Brassica napus plants. Proteobacteria , Actinobacteria , Chloroflexi, and Bacteroidetes were the predominant phyla. Key genera enriched in the rhizosphere included Sphingomonas , Streptomyces , Bacillus, and Pseudomonas. Salinity stress increased the abundances of Chloroflexi and Acidobacteria while decreased Actinobacteria. Rhizosphere communities of salt-treated plants showed lower diversity but separate clusters from controls, indicating salinity-induced shifts. Predictive functional analysis revealed that amino acid/carbohydrate metabolism and membrane transport pathways in salt-stressed rhizospheres were elevated. This study provides novel insights into the rhizosphere bacteriome of Brassica napus under salinity, highlighting potential plant-growth-promoting taxa for stress amelioration. • Bacteriome diversity and abundance of Brassica was influenced by salinity. • Salt stress conditions increased the abundance of some genera while reduced other genera. • There was a huge difference in the bacteriome of bulk soil and Brassica rhizosphere. [ABSTRACT FROM AUTHOR]

Uncovering the environmental drivers and revealing the balance between methanogenesis and methanotrophy under different watering regimes are vital for understanding methane (CH 4) emissions in rice paddies. Although the mechanisms and impacts of watering regimes on plant community structures in rice paddies have been intensively investigated, the methanogenic and methanotrophic reactions under drying stress that regulate CH 4 emissions remain unclear. Here, we examined the watering regimes of rice fields to elucidate how continuous flooding and dry cultivation impacted and regulated CH 4 emissions. Water-saving regimes (dry cultivation) significantly decreased CH 4 emissions (70–90 %) compared to the flooding treatment. The methanogenic and methanotrophic abundance, composition and structures were stable under the two watering regimes, while microbial interactions demonstrated that the dry cultivation had fewer positive links to methanogens in contrast to flooding. Furthermore, the more positive links to methanotrophs and limited electron transfer within rice plant communities under dry cultivation were observed, which subsequently restricted methanogenesis, translating to lower CH 4 emissions. Dry cultivation also weakened the correlations between environmental factors and methanogens, albeit strengthened the links to methanotrophs. Flooding treatment exhibited significantly positive electrical conductivity and dissolved organic carbon-methanogen correlations, which might have explained the higher CH 4 emissions than the dry cultivation. These findings suggested that drying treatment reduced microbial connectivity and abundance of methanogenic drivers in the microbial network, which decreased the CH 4 emissions compared with flooding treatment. • Drying and flooding treatments did not alter microbial communities or their abundance. • Drying treatment induced fewer links to methanogens but more so to methanotrophs in contrast to flooding. • Microbial networks and their interactions determined CH 4 emissions under experimental regimes. • Drying treatment weakened methanogenic activities and their connections with the environment. [ABSTRACT FROM AUTHOR]

Rhizosphere microorganisms play a vital role in enhancing plant health, productivity, and the accumulation of secondary metabolites. Currently, there is a limited understanding of the ecological processes that control the assembly of community. To address the role of microbial interactions in assembly and for functioning of the rhizosphere soil microbiota, we collected rhizosphere soil samples from Anisodus tanguticus on the Tibetan Plateau spanning 1500 kilometers, and sequenced the bacteria, fungi, archaea, and protist communities. We observed a significant but weak distance-decay relationship in the microbial communities of rhizosphere soil. Our comprehensive analysis of spatial, abiotic, and biotic factors showed that trophic relationships between protists and bacteria and fungi predominantly influenced the alpha and beta diversity of bacterial, fungal, and protistan communities, while abiotic factors had a greater impact on archaeal communities, including soil pH, available phosphorus, total phosphorus and mean annual temperature. Importantly, microbial interactions had a more significant influence on Anisodus tanguticus physiological and ecological functions compared to individual microorganisms. Network analyses revealed that bacteria occupy a central position of the co-occurrence network and play a crucial role of connector within this community. The addition of protists increased the stability of bacterial, fungal, and archaeal networks. Overall, our findings indicate that trophic relationships play an important role in assembly and for functioning of the rhizosphere soil microbiota. Bacterial communities serve as a crucial link between different kingdoms of microorganisms in the rhizosphere community. These findings help us to fully harness the beneficial functions of rhizosphere microorganisms for plants and achieve sustainable use of biological resources. [ABSTRACT FROM AUTHOR]

It is well known that the mosaic patches of alpine meadows are primarily shaped by plant-soil interactions. However, we know little about whether and how plant functional traits mediate the influence of edaphic factors on soil microbial diversity through the mass and diversity effects. In this study, we investigated plant functional traits in five distinctive of mosaic patches (communities) dominated by different plant functional groups in a Tibetan alpine meadow. We measured key functional traits for every plant species within each plot to calculate the functional composition (i.e., community-weighted mean, CWM) and structure (i.e., functional diversity, FD) of the plant community to examine the mass and diversity effects of plants on soil microbial diversity. In general, the difference in soil microbial diversity across the mosaic communities can be predicted by changes in CWM and FD of plant communities incorporating edaphic factors. The change in FD of five plant traits alone can predict 46% variation for soil bacterial richness, and up to 91% variation for soil fungal richness when the direct effect of edaphic factors was included. In response to variations in soil available phosphorus and pH, an increase in plant CWM and FD of leaf phosphorus and nitrogen content significantly promoted the richness of soil bacteria but lowered soil fungal richness. Hence, plant functional traits play a critical role in mediating the effects of edaphic factors on soil microbial diversity through mass and diversity effects. Our study not only illustrates the functional significance of plant traits in shaping plant-soil interactions in mosaic communities of the Tibetan alpine meadow but also promotes research linking biodiversity in mosaic patches to the functionality of the fragile alpine ecosystem. • Alpine ecosystems are characterized by mosaic communities in nested patches. • Plant traits influence soil microbes through mass and diversity effects. • Leaf nutrient traits are better than morphological traits in predicting soil microbes. • Soil bacterial and fungal richness is differently associated with plant traits. [ABSTRACT FROM AUTHOR]

[Display omitted] • We analyzed airborne antibiotic resistance genes (ARGs) in 72 neighborhoods. • The abundance of ARGs is affected by the surrounding land use and plant communities. • Warm seasons promote a surge in ARGs that transferred indoors. • VanA abundance positively correlated with the prevalence of respiratory diseases. Over the last few years, the cumulative use of antibiotics in healthcare institutions, as well as the rearing of livestock and poultry, has resulted in the accumulation of antibiotic resistance genes (ARGs). This presents a substantial danger to human health worldwide. The characteristics of airborne ARGs, especially those transferred from outdoors to indoors, remains largely unexplored in neighborhoods, even though a majority of human population spends most of their time there. We investigated airborne ARGs and mobile genetic element (MGE, IntI1), plant communities, and airborne microbiota transferred indoors, as well as respiratory disease (RD) prevalence using a combination of metabarcode sequencing, real-time quantitative PCR and questionnaires in 72 neighborhoods in Shanghai. We hypothesized that (i) urbanization regulates ARGs abundance, (ii) the urbanization effect on ARGs varies seasonally, and (iii) land use types are associated with ARGs abundance. Supporting these hypotheses, during the warm season, the abundance of ARGs in peri -urban areas was higher than in urban areas. The abundance of ARGs was also affected by the surrounding land use and plant communities: an increase in the proportion of gray infrastructure (e.g., residential area) around neighborhoods can lead to an increase in some ARGs (mecA , qnrA , ermB and mexD). Additionally, there were variations observed in the relationship between ARGs and bacterial genera in different seasons. Specifically, Stenotrophomonas and Campylobacter were positively correlated with vanA during warm seasons, whereas Pseudomonas , Bacteroides , Treponema and Stenotrophomonas positively correlated with tetX in the cold season. Interstingly, a noteworthy positive correlation was observed between the abundance of vanA and the occurrence of both rhinitis and rhinoconjunctivitis. Taken together, our study underlines the importance of urbanization and season in controlling the indoor transfer of airborne ARGs. Furthermore, we also highlight the augmentation of green–blue infrastructure in urban environments has the potential to mitigate an excess of ARGs. [ABSTRACT FROM AUTHOR]

Oxidative potential (OP) of particles is an emerging indicator of health that reflects their ability to induce oxidative stress and cause adverse health effects. It offers us a useful tool to evaluate the health effects of particles released by different industrial processes. We measured the OPv (volume normalized OP characterizes overall oxidative burden) and OPm (mass normalized OP characterizes intrinsic toxicity) of PM 2.5 from a casting workshop, a machining workshop, a meeting room of a machining processing plant, and outdoors using dithiothreitol (DTT) assay. The observed variations were substantial and varied greatly, underscoring the diverse toxicological profiles of particulates from distinct sources. Overall, PM 2.5 mass concentration and OPv were highest in the casting workshop (PM 2.5 : 669.26 ± 402.62 μg/m3, OPv: 69.55 ± 128.35 nmol/(min·m3)), followed by the machining workshop (PM 2.5 = 85.51 ± 41.89 μg/m3, OPv = :5.38 ± 2.68 nmol/(min·m3)), outdoor (PM 2.5 : 30.77 ± 13.34 μg/m3, OPv: 1.83 ± 0.92 nmol/(min·m3)), and meeting room (PM 2.5 : 26.97 ± 12.03 μg/m3, OPv: 1.86 ± 1 nmol/(min·m3)). However, localized variances influenced by PM's intrinsic toxicity (OPm) reordered these rankings. For example, PM 2.5 mass concentration at the spheroidizing/pouring zone in the casting workshop was the highest, but the OPv was not due to the low intrinsic toxicity of the particles. Spearman's correlation analysis implied that the OPv was significantly correlated with the concentration of transition metals Mn (ρ = 0.47, P < 0.01), Fe (ρ = 0.503, P < 0.01), and Zn (ρ = 0.507, P < 0.01) in addition to PM 2.5 mass concentration (ρ = 0.879, P< 0.01), and the OPm was significantly correlated with the mass fraction of Zn (ρ = 0.34, P < 0.05) and Al (ρ = 0.333, P < 0.05). Besides, environmental factors (wind speed, temperature relative humidity, CO 2) did not contribute to the oxidation potential. Higher oxidation potential (OPv) means higher health risks, our findings underscore the imperative to consider both PM mass concentration and intrinsic toxicity for future air pollution control efforts. [Display omitted] • OP of PM 2.5 from a mechanical processing plant was studied using DTT assay. • OP was shown to vary greatly with different locations across industrial environments. • Intrinsic toxicity OPm of PM 2.5 was significantly associated with mass fractions of Zn and Al. • Both PM mass concentration and intrinsic toxicity should be considered in air pollution control. [ABSTRACT FROM AUTHOR]

• The carbon sequestration benefits of 72 plant communities were quantified. • The relationship between community characteristics and carbon sink was discussed. • Increasing canopy density and tree density can improve the efficiency of carbon sequestration. • Increased mean DBH and community density are useful in the early and middle stages of growth. This research study identified the communal green at Nanjing Forestry University as an example and focused on the carbon sink benefits of the plant communities. Firstly, the representative plant communities in the communal green were investigated, and the parameters of the plant communities were established so that the carbon sink benefits of each plant community could be quantified. Secondly, by applying correlation analysis to study the influence degree of varied plant community factors on the benefits of carbon sink, it was found that the canopy closure, diameter class structure and tree density showed significant positive correlation; the correlation between community density and daily carbon sequestration per unit area was significant; the correlation between community density and carbon storage per unit area showed none significance; and the correlation between the proportion of trees and shrubs and the carbon sink benefits was of no significance. Thirdly, regression analysis was used to study the curve trends of the carbon sink benefits of the plant communities, from which it was concluded that increasing canopy density, average plant height, average crown width and tree density will improve carbon sink benefits. Increasing the average DBH would achieve positive effects for increasing daily carbon sequestration per unit area only at the early stage of the community growth. The plant community density showed positive effects on the increase of the daily carbon sequestration per unit area within a limited range. Since most regression formulas resulted in S-curves, certain threshold bottlenecks were found existed of improving the carbon sinks benefits by increasing the plant community factors. Finally, the characteristics of plant communities with high carbon sink benefit were summarized to provide theoretical references for forming a planting optimization strategy of urban green. [ABSTRACT FROM AUTHOR]

• Increasing important values of Asteraceae and weeds with degradation of inland salt marsh wetlands. • Higher plant diversity in moderate degraded wetlands. • Soil carbon and nitrogen content declines significantly with wetland degradation. • Soil nitrogen content is a key element in wetland degradation processes. Plant community characteristics and soil properties are critical indicators for evaluating wetland degradation and restoration. In order to investigate how the degradation of inland salt marsh wetlands affects plants and soils as well as the response relationship between plants and soils under different degradation degrees, this paper selected inland salt marsh wetlands with different degradation degrees in the wetland area of western Songnen Plain, and analyzed the characteristics of plant communities, soils and their relationships. The results show that: that the important value of Gramineae plants decreased by about 21% with increasing degradation, while the vital value of Cyperaceae and weeds increased by 10% and 9%, respectively. Plant height decreased significantly, and coverage and density showed a decreasing and then increasing trend. Overall, species diversity shows a trend of increasing and then decreasing, indicating that the structure of plant communities tends to be more straightforward and more complex with increasing degradation. Soil electrical conductivity, total organic carbon (TOC) and total nitrogen (TN) content decreased significantly with the degree of degradation from ND (non degradation) to HD (heavy degradation) by 34.08%, 19.56%, and 35.82%, respectively. Soil C:N increased from 13.13 to 17.97. Soil N:P and C:P decreased from 5.56 to 3.28 and from 71.59 to 54.02, respectively. Soil factors affecting wetland plants were inconsistent at different stages of degradation. Changes in soil nitrogen and phosphorus content were correlated with changes in wetland vegetation community structure. Therefore, exploring how wetland degradation affects plants and soils can provide a scientific basis for wetland degradation assessment and wetland restoration. [ABSTRACT FROM AUTHOR]

The contributions of soil and plant diversity to supporting ecosystem functions in urban greenspaces remains little known. Soil compaction and nutrient enrichment constitute major threats, and can give rise to the loss of ecosystem services in urban greenspaces. Our study focused on spontaneous vegetation in urban greenspaces in a Mediterranean city. We aimed to study the network correlations between the physical-chemical and biological properties of the soil at different depths along gradients of soil disturbance; and to analyse how vegetation and soil depth influence soil functioning. We focused our study on the following four spontaneous ruderal vegetation types: open vegetation on trampled soils, roadside vegetation, annual grasslands, and perennial forbs. They are widely distributed in Mediterranean urban greenspaces along soil compaction and nutrient enrichment gradients. We determined soil physical-chemical properties (organic matter, available nutrient content) and soil microbial activity relating to the main macro-nutrient cycles in the soil under each vegetation type at different soil depth (0–5, 5–20 cm). We used Spearman's bivariate correlations to study the relationships between soil variables at different soil depths by means of network analysis. We performed two-way ANOVAs to determine the influence of the plant-community type and soil depth on soil physical-chemical parameters and enzyme activity. We found that physical-chemical variables such as total organic carbon and bulk density represented the main drivers of soil functionality in the surface horizon (0–5 cm). Enzyme activity, however, associated with cycles of macronutrients such as arylamidase, arylsulfatase and phosphatase, had a greater influence on ecosystem functions in the subsurface horizon (5–20 cm). Regardless of the soil depth (0–5 cm, 5–20 cm), ANOVAs revealed a significant increase in bulk density between trampled soils (lowest values) and roadside vegetation (highest values); and in available phosphorus between annual grasslands (lowest scores) and perennial forbs (highest scores). Soils under annual grasslands and perennial forbs showed the greatest number of significant differences in soil between horizons. The highest number of significant differences were found between vegetation types in the surface soil horizon (0–5 cm) for soil organic matter and enzyme activities. This research therefore suggests that in urban Mediterranean greenspaces soil horizons are dissociated in terms of their soil parameter drivers, and that the surface horizon (0–5 cm) is more closely related to the response of the vegetation to soil disturbance gradients than the subsurface horizon (5–20 cm). [Display omitted] • Surface horizon was found dissociated from the subsurface horizon in urban-greenspaces. • Soil biological properties drove the subsurface horizon (5–20 cm). • Soil physical-chemical parameters were most important in the surface horizon (0-5 cm). • Soil gradients in organic matter and compaction were well described by vegetation. [ABSTRACT FROM AUTHOR]

• Climate change impact on grassland growth and floristic composition was quantified. • Plant community dynamics were explicitly simulated with process-based approaches. • A clear decline of forage production was observed as response to climate change. • Changes in floristic composition can counterbalance negative effects of climate. • The adaptation strategies defined can support grassland-related ecosystem services. Grasslands are environments characterized by an elevated biodiversity in plant species, which dynamically evolves over time as a function of management practices, soil properties, and climate conditions. Climate change can locally affect grassland growth and floristic composition and, in turn, the quality and quantity of provided ecosystem services. We show how the use of the plant community model CoSMo allows to explicitly account for the dynamics of floristic composition as response to environmental variables. This, in turn, allows quantifying climate change impacts on grasslands growth and composition and evaluating alternative strategies to improve adaptation in the mid-term. As a case study, we focused on mountain areas in the northern Apennines (Italy), where temporary alfalfa (Medicago sativa L.)-dominated grasslands are sown for the production of Parmesan cheese. Five sites and four alternative climate scenarios (RCP4.5 and RCP8.5 projections as provided by the HadGEM2 and GISS general circulation models) were considered, to explore a wide range of agro-environmental conditions. Results showed that the observed dynamics of floristic composition and biomass accumulation were successfully simulated, with a mean absolute error lower than 10% for floristic composition and less than 1 t ha−1 for total biomass. Climate change impacts were globally negative, with a clear decrease of forage production as compared to the baseline (from -3.6% to -14.3% according to the climate scenario). The biodiversity of the plant community also declined (12.5% average decrease in the inverse Simpson index) due to the increase in alfalfa dominance. The latter, however, led to preserve the forage crude protein content (+0.9% on average). Guidelines for optimizing grassland productivity and forage protein under future climate were defined, mainly focused on reducing the alfalfa field duration, sowing grass-legume mixtures, and delaying the last cut of the season. These practices can be easily adopted under operational farming conditions to support the adaptation of temporary grasslands to climate change. According to our knowledge, this is one of the first study of climate change impact that uses a plant community model to explicitly considers phytocoenosis dynamics, biodiversity, and their effect on forage production (quantity and quality). Considering the role of grasslands as providers of key ecosystem services ‒ especially in marginal areas ‒ we believe that our modelling approach can support the identification of effective adaptation strategies to address future climate challenges. [Display omitted] [ABSTRACT FROM AUTHOR]

The ongoing debate on the causes and modalities of the Messinian Salinity Crisis (MSC) from 5.971 Ma needs to be implemented by an in-depth knowledge of the events and changes, on a global to regional scale, that have preceded its onset. Here we use palynological (pollen and dinocysts) and micropaleontological (foraminifers and calcareous nannoplankton) quantitative analyses from the Govone sedimentary succession (Northern Italy, western Mediterranean) to reconstruct the cyclical changes in atmosphere, surface, and deep-water hydrographic conditions during the Late Miocene, prior to the onset of the MSC (from ca 6.6 Ma) and across it (up to 5.96 Ma). On land, plant communities were dominated by arboreal life forms typical of warm and humid conditions. However, mid- to high altitude coniferous taxa attest to a sequence of cold to cool conditions, some coinciding with glacial obliquity-controlled phases, notably those across the MSC onset (i.e. TG34 and TG32). Dominant trees were Taxodioideae, especially in freshwater swamps, during warm and humid phases. The latter alternate with relatively less warm, and less humid phases characterised by the reduction of Taxodioideae, according to the precession-controlled sedimentary cyclicity (sapropel-marl couplets). The absence of any significant expansion in the herbaceous cover is evidence of no substantial increases in aridity at insolation minima. In the marine realm, the precession-controlled cycles correspond to prevalent alternations between warm water, oligotrophic (sapropel, insolation maxima) and cool water, eutrophic (marls, insolation minima) conditions. The progressive decrease of oceanic/outer neritic dinocyst taxa, along with a more continuous occurrence of the inner neritic ones, confirm the progressive restriction of Mediterranean and Atlantic connections, despite oceanic influxes, the latest at 6.14 Ma and 6.05 Ma. On the other hand, the occurrence of freshwater episodes, according to dinocysts, does not exclude possible connections with Paratethys, at 6.18 Ma and 6.07 Ma. All calcareous nannoplankton and foraminifera apparently disappear from the sedimentary record before the onset of the MSC, at ca 6.02 Ma; however, dinocysts allow the documentation of the history of pre-evaporitic conditions up to the beginning of the MSC onset, when lagoons, marked by frequent salinity changes, expanded in the inner neritic zone of the Govone intermediate depth basin, during ca 60 kyrs. Plant assemblages attest a long-lasting increase of seasonality (from 6.2 Ma) as well as a peculiar inversion in the dominant vegetal patterns of the sapropel-marl couplets, between ca 6.02 Ma and 5.96 Ma, corresponding to the uppermost four cycles. The significant restriction of the marine environment, after 6.02 Ma, possibly promoted atmospheric changes marked by reduced vs enhanced activity of the Mediterranean storm-track in phase with precession. This, in turn, regulated the amounts of runoff in the Northern Italian sectors from the Alps. • Humid conditions persist across the MSC in the northern Mediterranean. • Broad-leaved evergreen-warm mixed forests extended north of 42°N in the Mediterranean. • Calcareous microfossils vanished from sediments 50 ka before the MSC onset. • Dinocysts trace the aquatic environmental changes across the MSC onset. • Nannobarbophora , a warm acritarch, marks the MSC onset. [ABSTRACT FROM AUTHOR]

Plant root exudates serve pivotal roles in supporting plant development and interactions with the physicochemical and biological factors in the rhizosphere. Under stress conditions, root exudation is involved in enhancing plant resource-use efficiency and facilitating the crosstalk between plant and soil microbes to ameliorate stress. Although there are a large number of root exudates that remain to be characterized, recent technological advancements have allowed for the function of many exudate compounds to be elucidated. In this review, we discuss current knowledge about the key root exudates that modulate plant resource-use efficiency under various abiotic stresses including drought, aluminum toxicity, phosphorus, nitrogen, and iron deficiency. The role that key root exudates play in shaping microbial communities in the rhizosphere under stress conditions is also an important consideration addressed in this review. Root exudation plays important roles in plant interactions with soil chemical factors and belowground microorganisms that impact abiotic stresses. Carboxylate efflux is a key mechanism for plant phosphorus acquisition and tolerance to aluminum. Phenolics are utilized by dicots and non-graminaceous monocots while phytosiderophore exudation is used by grasses to mobilize iron for root uptake. Secondary metabolites such as flavonoids and strigolactones facilitate plant association with mycorrhizal fungi under drought and phosphorus-deficient conditions. Under nitrogen-limited conditions root exudates facilitate plant associations with nitrogen-fixing microbes and may reduce losses of soil nitrogen through inhibition of the bacteria involved in nitrification and denitrification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Supplementation of acetic acid (500–1500 mg/L) decreased plant yields in bioponics. • Acetic acid did not significantly affect N, P, and COD concentrations. • Acetic acid affected some microbial OTUs and metabolic genes in the bioponics. • Organic degradation and nutrient mineralization by microbes occurred symbiotically. • Root microbes functioned symbiotically for nutrient transformation and recovery. Bioponics has the potential to recover nutrients from organic waste streams, such as chicken manure and digestate with high volatile fatty acid (VFA) contents through crop production. Acetic acid, a dominant VFA, was supplemented weekly (0, 500, 1000, and 1500 mg/L) in a chicken manure-based bioponic system, and its effect on the performance of bioponics (e.g., plant yield and nitrogen and phosphorus availabilities) was examined. Microbial communities were analyzed using 16S rRNA gene sequencing, and the functional gene abundances were predicted using PICRUSt. Although acetic acid negatively affected plant yield, no significant difference (p > 0.05) was noted in the average nitrogen or phosphorus concentration. In terms of nutrient recovery, the bioponic systems still functioned well, although higher concentrations of acetic acid decreased plant yield and altered the bacterial communities in plant roots and chicken manure sediments. These data suggest that an acetic acid concentration of < 500 mg/L or a longer loading interval is recommended for the effective operation of chicken manure and digestate-based bioponics. [ABSTRACT FROM AUTHOR]

● Hakea drupacea reduces the diversity of native plant species probably through the effect of litter production and canopy cover ● Uninvaded sites had higher numbers of native plant species compared to invaded sites ● Litter depth was significantly higher in invaded sites compared to uninvaded and cleared sites ● Active removal of H. drupacea restored native species in previously invaded sites The influence of invasive alien plants on plant community structure and above ground biomass in their novel range is poorly understood, as the magnitude and direction of these effects are often species and ecosystem specific. Here we compared community metrices of native plants and soil properties between study sites invaded by Hakea drupacea , uninvaded sites and cleared sites (sites formerly invaded by H. drupacea). A total of 129 plant species belonging to 75 genera were recorded across all study sites. Invasive Acacia saligna, A. longifolia, A. cyclops (Fabaceae) and Leptospermum laevigatum (Myrtaceae) co-occurred with H. drupacea in the invaded sites. Overall plant species richness, which constituted higher number of native plant species, was recorded in uninvaded sites compared to invaded and cleared sites. Plant species composition was similar between uninvaded and cleared sites, but species composition recorded in uninvaded and cleared sites were significantly different from species composition recorded at invaded sites. Litter depth was significantly higher in invaded sites compared to uninvaded and cleared sites. Hakea drupacea did not affect soil properties in invaded sites. Here we show that H. drupacea probably reduces the diversity of native plant species especially in invaded sites probably through the effect of litter production and canopy cover, pointing to a beneficial effect of removal of H. drupacea. We encourage active restoration of sites invaded by H. drupacea at early stages of invasion before the plants become established and suppress the growth of native species. [ABSTRACT FROM AUTHOR]

Automatic identification of plant specimens from amateur photographs could improve species range maps, thus supporting ecosystems research as well as conservation efforts. However, classifying plant specimens based on image data alone is challenging: some species exhibit large variations in visual appearance, while at the same time different species are often visually similar; additionally, species observations follow a highly imbalanced, long-tailed distribution due to differences in abundance as well as observer biases. On the other hand, most species observations are accompanied by side information about the spatial, temporal and ecological context. Moreover, biological species are not an unordered list of classes but embedded in a hierarchical taxonomic structure. We propose a multimodal deep learning model that takes into account these additional cues in a unified framework. Our Digital Taxonomist is able to identify plant species in photographs better than a classifier trained on the image content alone, the performance gained is over 6 percent points in terms of accuracy. [ABSTRACT FROM AUTHOR]

A longstanding research divide exists in plant ecology: either focusing on plant clonality, with no ambition to address nonclonal plants, or focusing on all plants, ignoring that many ecological processes can be affected by the fact that some plants are clonal while others are not. This gap cascades into a lack of distinction and knowledge about the similarities and differences between clonal and nonclonal plants. Here we aim to bridge this gap by identifying areas that would benefit from the incorporation of clonal growth into one integrated research platform: namely, response to productivity and disturbance, biotic interactions, and population dynamics. We are convinced that this will provide a roadmap to gain valuable insights into the ecoevolutionary dynamics relevant to all plants. Clonal plants can represent a substantial proportion of species in floras and plant communities. Because they share several functions that are not present in nonclonal plants, the differences in their proportions are likely to scale up as community and ecosystem differences. Clonal reproduction is provided by specialized organs that directly or indirectly affect other plant traits. Clonal growth organs usually serve for the storage of carbohydrates and the buildup of the bud bank, both necessary for resprouting in recurrently disturbed habitats. These storage organs affect global carbon cycling. Clonal growth leads to increased plant size in the horizontal dimension and to different degrees of ramet aggregation that influence the exploration of soil resources, pollination, and biotic interactions. Clonal growth serves as a reproductive insurance mechanism that further affects plant demography and possible evolutionary rates. [ABSTRACT FROM AUTHOR]

High biodiversity increases ecosystem functions; however, belowground facilitation remains poorly understood in this context. Here, we explore mechanisms that operate via 'giving–receiving feedbacks' for belowground facilitation. These include direct effects via root exudates, signals, and root trait plasticity, and indirect biotic facilitation via the effects of root exudates on soil biota and feedback from biota to plants. We then highlight that these two- or three-way mechanisms must affect biodiversity–ecosystem function relationships via specific combinations of matching traits. To tango requires a powerful affinity and harmony between well-matched partners, and such matches link belowground facilitation to the effect of biodiversity on function. Such matching underpins applications in intercropping, forestry, and pasture systems, in which diversity contributes to greater productivity and sustainability. Belowground facilitation is a vital mechanism underlying ecosystem function in diverse plant communities. A bottleneck to linking theory to application is that interspecific belowground facilitation processes are incompletely understood. Here, we explore direct and indirect facilitation, which requires matching specific belowground responses between the facilitated species and the facilitator. Understanding and integrating the processes of interspecific facilitation helps to design sustainable diverse plant communities with compatible ecosystem functions. [ABSTRACT FROM AUTHOR]

In this paper, the first results of charcoal analyses carried out at Cova des Moro (Manacor, Mallorca, Spain) are presented. This cave is an archaeological but also palaeontological site that provides information on endemic fauna (the extinct caprine Myotragus balearicus) before the arrival of humans and, later, the relationship between the first farmers and the landscape. Several human occupations in the cave have been documented, from the Chalcolithic (end of the 3rd millennium cal BC), the Bronze Age (2nd millennium cal BC) and, finally, the Almohad period (13th century AD), during which the cave was used for different purposes. The first results of charcoal analyses at Cova des Moro provide information about the natural plant communities exploited by humans for comparison with later sequences, enabling us to evaluate how humans managed this territory over time. The results point to the exploitation of Mediterranean woodlands with wild olive (Olea europaea), mastic (Pistacia lentiscus), green olive tree (Phillyrea), Aleppo pine (Pinus halepensis), rosemary (Rosmarinus officinalis), juniper (Juniperus) and rockrose species (Cistus), among others; these taxa would become the main elements of Mallorca's coastal landscape in later times, and it has been proven that they would already have been present as the island's natural flora at the time humans arrived there. [ABSTRACT FROM AUTHOR]

[Display omitted] Crop-associated microorganisms are known to have a determining influence on crop growth and resistance to stresses. Indeed, microorganisms can deter pathogens, reduce stress levels, improve nutrition, and stimulate growth. However, the microbial communities associated with a plant are rarely optimal for agricultural needs. But how can we engineer crops-associated microbial communities? An interesting framework to address this question is the theory of ecological communities that stipulates four processes by which communities can change: 1) selection, 2) dispersal, 3) speciation and 4) ecological drift. Of these, speciation and dispersal can result in the addition of new species to the plant microbiota, whereas selection and drift can lead to the loss of species. We believe that if these mechanisms are sufficiently understood, they could be harnessed to purposefully engineer the crop microbiota. Here, we will discuss the recent efforts to modify the phenotype of plants that are aligned with these ecological processes. [ABSTRACT FROM AUTHOR]

Ticks have an unparalleled ability to parasitize diverse land vertebrates. Their natural persistence and vector competence are supported by the evolution of sophisticated hematophagy and remarkable host immune-evasion activities. We analyze the immunomodulatory roles of tick saliva which facilitates their acquisition of a blood meal from natural hosts and allows pathogen transmission. We also discuss the contrasting immunological events of tick–host associations in non-reservoir or incidental hosts, in which the development of acquired tick resistance can deter tick attachment. A critical appraisal of the intricate immunobiology of tick–host associations can plant new seeds of innovative research and contribute to the development of novel preventive strategies against ticks and tick-transmitted infections. Ticks can repeatedly parasitize their permissive reservoir hosts. Recent studies suggest that the tick bite sites reflect a broad sessile lesion without signs of pain or itchiness, despite intense inflammation. These observations reinforce the 'immune evasion theory', where the tick sialome can efficiently engage and evade immune responses in permissive hosts. Many non-natural or incidental hosts, potentially including humans, can develop acquired tick resistance against repeated tick bites. New research has uncovered key factors that drive these tick rejections in resistant hosts, suggesting diversity in the architectural, sensory, and neurological aspects of tick bite lesions and the types of host responses. Although research has yet to identify the precise tick proteins that trigger the host responses associated with tick rejection in incidental hosts, new studies suggest that repeated host exposure to tick saliva, specifically its glycoproteins or particular saliva fractions, can independently drive partial immunity against tick bites. [ABSTRACT FROM AUTHOR]

Plant–soil feedback (PSF) and diversity–productivity relationships are important research fields to study drivers and consequences of changes in plant biodiversity. While studies suggest that positive plant diversity–productivity relationships can be explained by variation in PSF in diverse plant communities, key questions on their temporal relationships remain. Here, we discuss three processes that change PSF over time in diverse plant communities, and their effects on temporal dynamics of diversity–productivity relationships: spatial redistribution and changes in dominance of plant species; phenotypic shifts in plant traits; and dilution of soil pathogens and increase in soil mutualists. Disentangling these processes in plant diversity experiments will yield new insights into how plant diversity–productivity relationships change over time. Plant diversity–productivity relationships often become stronger over time, but we know little about what biotic mechanisms may drive temporal dynamics of diversity–productivity relationships. Recent advances in plant-soil feedback (PSF) research can help gain new mechanistic insights into temporal dynamics of diversity–productivity relationships. We suggest three processes driving temporal changes in PSF of individual plants in diverse plant communities: spatial redistribution and changes in the dominance of plant species; phenotypic shifts in plant traits; and dilution of soil pathogens and increase in soil mutualists. These three processes reduce the strength of negative feedback in the absence of external disturbances and make diverse plant communities more productive over time. [ABSTRACT FROM AUTHOR]