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Distributions of plants are expected to change in response to climate change, but the relative probability of that change is often unknown. Curl-leaf mountain mahogany (Cercocarpus ledifolius), an important browse species used by ungulates as forage and cover across the western US, is thought to be moderately to highly vulnerable to climate change this century, and a reduction in curl-leaf mountain mahogany occurrence may negatively impact ungulates reliant upon it. A combination of probability density estimation and vector analysis was used to predict curl-leaf mountain mahogany distribution across the species range relative to climate space and how that relationship would affect curl-leaf mountain mahogany at a local scale. Locally, we used the curl-leaf mountain mahogany population at the Bighorn Canyon National Recreation Area (BICA) in Montana and Wyoming for comparison. We modeled the probability of curl-leaf mountain mahogany occurrence across its distribution using water balance data to spatially and temporally assess the vulnerability of a population at a local scale. Modeled probabilities of occurrence and vector analysis indicated the species to remain in some areas within BICA but will be vulnerable in others given the predicted changes in temperature and precipitation in BICA if historical trajectories continue. This information allows managers to direct limited resources to other management actions by using the best available science to inform decisions. Other curl-leaf mountain mahogany populations currently inhabiting wetter, drier sites may follow a similar trajectory as the effects of climate change manifest. The approach used serves as a model to assess the predicted trend for species-specific plant communities of concern that may be adversely affected by climate change. [ABSTRACT FROM AUTHOR]

Sustainable Urban Drainage Systems (SUDS) are ecosystems that are based on engineered soil and designed plant communities to manage stormwater on-site and to enhance infiltration, evapotranspiration, and cooling, thus reducing flooding and urban heat islands. In addition, SUDS may act as hotspots for biodiversity and could be more socially accepted if they work well and are multifunctional. However, we still lack a critical understanding of the techno-ecological basis to construct SUDS sustainably. Due to climate change and pollutants such as de-icing salts, SUDS are confronted with harmful environmental triggers that interfere with their sustainable development. Thus, the challenge is to combine stormwater treatment and urban drainage with principles of restoration ecology, while implementing expertise from soil science, microbiome research, and plant ecology. In this perspective paper, we will discuss the SUDS development and maintenance principle and the role of interdisciplinary research in reaching these goals. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to examine the community characteristics of grassland plants in the Habahe region of Altai Mountains, changes in plant diversity, aboveground biomass in relation to community stability, and to provide data support for the development of a rational grazing system in Habahe region. [Methods] From 2020 to 2022, 18 representative fixed sample plots were selected in the summer pasture of Habahe in Altai Mountains to do surveys to investigate the number of species in the sample plots, cover and height, etc., and to determine the aboveground biomass, β-diversity (Sφrensen β-diversity index and Jaccard β-diversity index), species diversity (Margalef richness index, Simpson dominance index, Shannon-Wiener diversity index and Alatalo evenness index) and M. Godron community stability. The relationship between community stability and plant diversity and its biomass before and after grazing was analyzed. [Results] (1) 30 species of grassland communities were distributed in the Habahe region of Altai Mountains, belonging to 14 families, with Asteraceae, Rosaceae and Gramineae in the majority. (2) The diversity index, cover, plant height and above-ground biomass of grasslands in the Habahe region showed a significant downward trend after grazing. (3) The stability of grassland communities in the Habahe region before grazing was positively correlated with the Margalef richness index, the Simpson dominance index, and the Shannon-Wiener index diversity index in a highly significant way (p＜0.01); and the stability of grassland communities in the Habahe region after grazing was positively correlated with the Simpson dominance index in a significant way (p＜0.05) . (4) The relationship between grassland community stability and aboveground biomass in the Habahe region before grazing showed a significant positive correlation (p＜0.05), and the relationship between grassland community stability and aboveground biomass in the Habahe region after grazing showed no correlation. [Conclusion] The relationship between grassland community stability and diversity and biomass changed significantly after grazing, and grazing had a greater impact on community stability and reduced the stability of the community to a certain extent, but the community was generally in a stable state. [ABSTRACT FROM AUTHOR]

Most terrestrial plants can establish a reciprocal symbiosis with arbuscular mycorrhizal (AM) fungi to cope with adverse environmental stresses. The development of AM symbiosis is energetically costly and needs to be dynamically controlled by plants to maintain the association at mutual beneficial levels. Multiple components involved in the autoregulation of mycorrhiza (AOM) have been recently identified from several plant species; however, the mechanisms underlying the feedback regulation of AM symbiosis remain largely unknown. Here, we report that AM colonization promotes the flavonol biosynthesis pathway in tomato (Solanum lycopersicum), and an AM‐specific UDP‐glucosyltransferase SlUGT132, which probably has the flavonol glycosylation activity, negatively regulates AM development. SlUGT132 was predominantly expressed in the arbuscule‐containing cells, and its knockout or knockdown mutants showed increased soluble sugar content, root colonization level and arbuscule formation. Conversely, overexpression of SlUGT132 resulted in declined soluble sugar content and mycorrhization degree. Metabolomic assay revealed decreased contents of astragalin, tiliroside and cynaroside in slugt132 mycorrhizal roots, but increased accumulation of these flavonoid glycosides in SlUGT132‐overexpressing plant roots. Our results highlight the presence of a novel, SlUGT132‐mediated AOM mechanism, which enable plants to flexibly control the accumulation of soluble sugars and flavonoid glycosides in mycorrhizal roots and modulate colonization levels. Summary statement: The mechanism underlying the autoregulation of mycorrhiza by plants remains elusive.This work uncovers a negative role of an UDP‐glucosyltransferase SlUGT132 in regulating mycorrhizal symbiosis in tomato, via modulating the accumulation of soluble sugars and certain flavonols in colonized roots. [ABSTRACT FROM AUTHOR]

Vineyards are highly intensive systems very often located in biodiversity hotspots at the global scale. These ecosystems are now facing major environmental, agronomical and economic issues that challenge their sustainability. Based on multiple evidence, I illustrate here how biodiversity and several nature-based solutions across scales, from manipulating within-field plant communities to landscape-scale diversification, can provide benefits related to key societal challenges that vineyard socio-ecosystems are facing. These findings support the idea that biodiversity and ecosystem services play a key role in the functioning of these landscapes and that nature-based solutions offer a sustainable pathway for the future of vineyard agroecosystems. This literature review also highlights several gaps of knowledge that define a research agenda for nature-based solutions to strengthen multifunctionality of vineyard landscapes. [ABSTRACT FROM AUTHOR]

Background: A growing body of evidence demonstrates that host-associated microbial communities of plant leaf surfaces (i.e. the phyllosphere) can influence host functional traits. However, it remains unclear whether host selection is a universal driver of phyllosphere community assembly. We targeted mānuka (Leptospermum scoparium) and three neighbouring non-mānuka plant species along an 1800-m transect in a New Zealand native bush to conduct a hypothesis-driven investigation of the relative influence of host species identity and stochastic dispersal on the composition of natural phyllosphere bacterial communities. Results: We detected significant correlations between host species identity and mānuka phyllosphere communities that are consistent with a dominant role of host selection in the assembly of the mānuka phyllosphere microbiome. In contrast, the phyllosphere community compositions of neighbouring, ecologically similar native plants were highly variable, suggesting that stochastic processes, such as dispersal, had a stronger influence on the phyllosphere microbiomes of those non-mānuka plants compared to the phyllosphere microbiome of mānuka. Furthermore, the distribution of phyllosphere taxa among plant species was congruent with a scenario in which microorganisms had dispersed from mānuka to non-mānuka phyllosphere microbiomes. Conclusions: We conclude that host selection of phyllosphere communities is not and should not be presumed to be a universal trait across plant species. The specificity of the mānuka phyllosphere microbiome suggests the presence of functionally significant bacteria that are under direct, possibly chemically mediated, selection by the host. Furthermore, we propose that phyllosphere microbiomes under strong host selection, such as that of mānuka, may act as a source of microorganisms for the phyllosphere microbiomes of neighbouring plants. 2ZqHFcd3Z-Di37dyajupxd Video Abstract [ABSTRACT FROM AUTHOR]

Understanding how land use affects temporal stability is crucial to preserve biodiversity and ecosystem functions. Yet, the mechanistic links between land-use intensity and stability-driving mechanisms remain unclear, with functional traits likely playing a key role. Using 13 years of data from 300 sites in Germany, we tested whether and how trait-based community features mediate the effect of land-use intensity on acknowledged stability drivers (compensatory dynamics, portfolio effect, and dominant species variability), within and across plant and arthropod communities. Trait-based plant features, especially the prevalence of acquisitive strategies along the leaf-economics spectrum, were the main land-use intensity mediators within and across taxonomic and trophic levels, consistently influencing dominant species variability. Functional diversity also mediated land-use intensity effects but played a lesser role. Our analysis discloses trait-based community features as key mediators of land-use effects on stability drivers, emphasizing the need to consider multi-trophic functional interactions to better understand complex ecosystem dynamics. [ABSTRACT FROM AUTHOR]

Herbivores are generally considered to reduce plant fitness. However, as in natural communities they often feed on several competing plant species, herbivores can also increase plant fitness by reducing interspecific competition among plants. In this study, we developed a testable model to predict plant fitness in the presence of an interspecific competitor and a herbivore that feeds on both plant species. Our model allows prediction of the herbivore and competitor densities at which the focal species will benefit from herbivory. This can be estimated by quantifying the effects of the herbivore on the fitness of the focal plant and on its competitor, and by estimating the levels of intra- and interspecific competition in a pairwise fashion, respectively. We subsequently validated the model in indoor microcosms using three interacting species: an aquatic macrophyte (the giant duckweed Spirodela polyrhiza), its native competitors (green algae) and its native herbivore (the pond snail Lymnaea stagnalis). Additional outdoor mesocosm experiments supported our model under natural conditions. Together, this study provides a conceptual framework to understand how herbivores shape plant fitness in a community context. [ABSTRACT FROM AUTHOR]

Studying the characteristics of soil moisture in afforestation area and its response to different grades of rainfall is helpful to quantitatively analyze the change law of soil moisture in afforestation area and provide theoretical basis for rational and efficient use of soil moisture. In this study, four artificial plant communities were selected, including Hedysarum scoparium community, Calligonum mongolicum community, H. scoparium- C. mongolicum community and C. mongolicum- H. scoparium community. The soil moisture content, soil moisture storage and their response characteristics to different grades of rainfall from June to October were compared and analyzed. The results showed that the SMC of H. scoparium- C. mongolicum community and C. mongolicum- H. scoparium community were lower than that of H. scoparium community and C. mongolicum community. The coefficient of variation of soil moisture content in C. mongolicum community was the largest, which was 22.7%, and the coefficient of variation of soil moisture content in H. scoparium-C. mongolicum community was the smallest, which was 19.4%. The recharge of rainfall to soil moisture storage of four artificial plant communities was different. The recharge of different grades of rainfall to soil moisture storage of C. mongolicum community and C. mongolicum-H. scoparium community was higher than that of H. scoparium community and H. scoparium-C. mongolicum community. In general, the utilization of soil moisture content in different soil layers by H. scoparium-C.mongolicum community is more balanced, and the soil moisture content in each soil layer is less affected by rainfall and has higher stability. Therefore, considering the configuration mode of H. scoparium- C. mongolicum community in the future aerial seeding afforestation process is conducive to the rational and efficient utilization of soil moisture in the afforestation area. [ABSTRACT FROM AUTHOR]

Dry evergreen Afromontane forests are severely threatened due to the expansion of agriculture and overgrazing by livestock. The objective of this study was to investigate the composition of woody species, structure, regeneration status and plant communities in Seqela forest, as well as the relationship between plant community types and environmental variables. Systematic sampling was used to collect vegetation and environmental data from 52 (20 m x 20 m) (400 m2) plots. Density, Diameter at Breast Height (DBH), basal area, frequency, and importance value index (IVI) of woody species were computed to characterize the vegetation structure of the forest. Agglomerative hierarchical cluster analysis and Canonical Correspondence Analysis (CCA) with R software were used to identify plant communities and analyse the relationship between plant community types and environmental variables, respectively. A total of 68 woody plant species belonging to 63 genera and 44 families were identified. The Shannon diversity index and evenness values of the study area were 2.12 and 0.92, respectively. The total basal area and density of woody species were 27.4 m2 ha−1 and 1079.3 individual ha−1, respectively. The most frequent woody species in the Seqela forest included Albizia gummifera (51.92%), Croton macrostachyus (44.23%), Olinia rochetiana and Teclea nobilis (36.54%). Additionally, the most dominant species, as indicated by their importance value index (IVI), were Erythrina brucei (IVI = 11.24), Prunus africana (IVI=8.68), and Croton macrostachyus (IVI=7.38). Four plant community types were identified: Albizia gummifera - Ekebergia capensis, Prunus africana - Croton macrostachyus, Vachellia abyssinica - Dombeya torrida and Schefflera abyssinica - Teclea nobilis. The CCA results showed that the variation of species distribution and plant community formation were significantly (P < 0.05) related to altitude, organic matter, aspect, slope and soil available phosphorus. The regeneration status assessment of the forest revealed a good regeneration status, which was linked to diverse and abundant seed bank in the soil can ensure a continuous supply of seeds for regeneration; therefore, it is recommended to implement periodic soil seed bank assessments to monitor seed diversity and abundance and inform targeted conservation actions. [ABSTRACT FROM AUTHOR]

Summary: Plants rely on solar energy for growth through photosynthesis, yet excessive light intensity can induce physiological damage. Despite the considerable harm, inadequate attention has been directed toward understanding how plant‐associated microorganisms mitigate this stress, and the impact of high light intensity on plant microbial communities remains underexplored. Through this Viewpoint, we aim to highlight the potential of microbial communities to enhance plant resilience and understand how light stress can shape plant microbiome. A full understanding of these dynamics is essential to design strategies that take advantage of microbial assistance to plants under light stress and to effectively manage the impact of changing light conditions on plant–microbe interactions. [ABSTRACT FROM AUTHOR]

Anthropogenic pressures such as hunting are increasingly driving the localised functional extinctions of large‐ and medium‐sized wildlife in tropical forests, a phenomenon broadly termed 'defaunation'. Concurrently in these areas, smaller‐bodied species benefit from factors such as competitive release and increase in numbers. This transformation of the wildlife community can impact species interactions and ecosystem services such as seed dispersal and seed‐mediated geneflow with far‐reaching consequences. Evidence for negative genetic effects following defaunation is well‐documented in large‐seeded plants that require large frugivores for long‐distance seed dispersal. However, how defaunation affects plants with small or medium‐small seeds (< 1.5 cm), which tend to be consumed and dispersed by frugivorous mutualists of a range of body sizes and responses to anthropogenic threats, is not well understood. To better understand defaunation's impacts on tropical plant communities, we investigated spatial and genetic patterns in a hyperabundant medium‐to‐small‐seeded palm, Euterpe precatoria in three sites with different defaunation levels. Results indicate that defaunation is associated with higher fine‐scale spatial genetic structure among seedlings and increased spatial clustering within seedling cohorts and between seedlings and conspecific adults, as well as a reduction in nearest‐neighbour distances between seedlings and conspecific adults. There were no clear effects on inbreeding or genetic diversity. However, we caution these trends may indicate that defaunation reduces seed dispersal services for species previously presumed to be robust to deleterious effects of losing large frugivores by virtue of having smaller seeds and broad suites of dispersal agents, and negative downstream effects on genetic diversity could occur. [ABSTRACT FROM AUTHOR]

Owing to its topographic variations, Ethiopia is a biodiversity-rich country. However, the long-term degradation of resources has resulted in isolated forest patches largely around sacred places. Thus, this work was aimed to evaluate the plant community formation and structural dynamics of the Abraham Sacred Forest patch. Data were collected from 60 plots located on transect lines. Five subplots (4 m2), four at each corner and center, were set to collect juveniles' data. Individuals of each species and cover abundance were recorded, and adults' stem girth was measured. Hierarchical cluster analysis was used to identify plant communities. A Kruskal-Wallis followed by Tukey's honestly significant difference test was performed to check the statistical significance among the plant communities. Shannon-Wiener diversity index, equitability index, and non-parametric species richness estimators were used to quantify species diversity, evenness, and richness, respectively. Structural parameters and size class ratios were used to analyze the vegetation structure and regeneration status. Seventy wood species, distributed in 62 genera and 38 families, were recorded. Fabaceae was the most species-rich (10 species) family. Three plant communities were identified. A Kruskal-Wallis test indicated that the community types showed significant differences (P < 0.05) with respect to altitude and slope. The density and basal area of the forest were 4580.4 ha-1 and 35.18 m2ha-1 respectively. The inverted J-shaped pattern in DBH classes implies a good reproduction status. However, importance value index and regeneration status analyses revealed that certain species, like Astropanax abyssinicum (Hochst. ex. A. Rich) Seem, Myrica salicifolia Hochst. ex. A. Rich and Dombeya torrida (G.F.Gmel) Bamps, require conservation priority. [ABSTRACT FROM AUTHOR]

Herein, we report the presence of a plant paleocommunity, dominated by ferns of the family Osmundaceae, structurally preserved from the only known Mesozoic, fossiliferous geothermal deposits, from the La Matilde Formation (Middle-Upper Jurassic) in the Deseado Massif of Southern Patagonia, Argentina. A total of 13 siliceous chert blocks sampled in an area of approximately 250 m2, preserving a monotypic assemblage dominated by Osmundaceae embedded within its original swampy substrate, are documented. Additional Osmundaceae and fewer ferns and conifers are present in the stratigraphically continuous, adjacent chert levels. This association is comparable to those dominated by Osmundaceae in modern swampy settings, such as in high-altitude lagoons in the Paraná Forest in Northeastern Argentina. In addition, a diverse community of mutualistic, parasitic, and saprotrophic microorganisms associated with the ferns and conifers in the assemblage is present. These compositional, paleoenvironmental, and trophic characteristics of the Jurassic Osmundaceae suggest a possible case of ecological stasis, where Osmundaceae-dominated plant communities apparently persisted in swamps of comparable structures, functions, and physical characteristics for over 150 million years. This suggests that Osmundaceae formed similar communities in compatible settings in the Jurassic, becoming preserved in analogous configurations. [ABSTRACT FROM AUTHOR]

Background: Fungal communities around plant roots play crucial roles in maintaining plant health. Nonetheless, the responses of fungal communities to bacterial wilt disease remain poorly understood. Here, the structure and function of fungal communities across four consecutive compartments (bulk soil, rhizosphere, rhizoplane and root endosphere) were investigated under the influence of bacterial wilt disease. Results: The results showed that bacterial wilt disease caused different assembly patterns of fungal communities in the bulk soil, rhizosphere, rhizoplane and endosphere. Under the influence of bacterial wilt disease, a decreased fungal diversity was observed in the rhizoplane and endosphere, and completely different kinds of fungal genera were enriched in the four compartments. The complexity and stability of fungal networks were less affected, but the number of key fungal members in networks were significantly reduced in diseased samples. Functional predictions based on FUNGuild suggested that with the pathogen infection, saprotrophic fungi were increased in the bulk soil, but pathotrophic fungi (potential plant and animal pathogens) were increased in the rhizosphere, rhizoplane and endosphere. Conclusion: This work provides a deep insight into the effects of bacterial wilt disease on fungal communities along the soil-root continuum, and is helpful to identify plant-associated beneficial fungi to resist plant disease. Clinical trial number: Not applicable. [ABSTRACT FROM AUTHOR]

To characterize the naturalized population of burr medic (Medicago polymorpha L.), a valuable pasture legume, in subtropical Queensland, Australia, a collection of 1747 lines from 107 sites in 11 regions was grown, and 26 phenotypic and agronomic attributes were recorded. This data matrix was analyzed by cluster, principal co-ordinates, discriminant and correlation analyses to examine line relationships based on plant attributes and their association with site characteristics of climate and soil. Among the wide polymorphism of attributes across the collection zone, there were a number of notable phenotypic associations. One of these, with large green leaves, minimally dentate leaf margins, and light purple petioles, was widely distributed. Three others, one with a distinctive magenta leaf mark, dark purple petioles, and an upright habit; one with those same attributes but with a prostrate habit; and one with grey-green leaves, high frost resistance, and the ability to stay green and to produce high pod yields, were associated with climatic and soil characteristics in the north, east, and south of the collection zone, respectively. Days to flowering were longer in lines from saline soils at lower altitude, and plant vigor was greatest in lines from more fertile soils with higher rainfall. A wide variation in time to flower of lines at all collection sites contributes to the adaptation of M. polymorpha in subtropical Queensland and potentially to its persistence with future climate change. [ABSTRACT FROM AUTHOR]

The rhizosphere bacterial community of plants has a crucial effect on healthy plant growth, and each rhizosphere has a specific microbial community. Camellia sinensis cv. Shifocui (C. sinensis cv. Shifocui) is a tea plant distributed in the Dabie Mountains of Anhui Province. It has the characteristics of high yield, good quality, strong cold resistance, and a high amino acid content. This study was the first to use 16S rRNA high—throughput sequencing technology and bioinformatics methods to explore the characteristics and functions of the rhizosphere bacterial community of the cold-tolerant tea tree C. sinensis cv. Shifocui, providing an important basis for the development and utilization of rhizosphere microbial resources. The dominant phylum in the rhizosphere microbes of the C. sinensis cv. Shifocui rhizosphere microorganisms were Proteobacteria, Chloroflexi, Acidobacteriota, and Actinobacteria. Network analysis showed significant positive and negative correlations among the rhizosphere bacterial groups of C. sinensis cv. Shifocui, among which Candidatus _ Xiphinematobacter, Acidobacteriale, Bradyrhizobium, Subgroup _ 2, Candidatus_Udaeobacter, Gemmataceae, and Gaiellales were notable nodes in the interaction networks. Functional prediction of FAPROTAX indicated that C. sinensis cv. Shifocui was rich in chemoheterotrophic, cellulose hydrolysis, and oxidative heterotrophic conditions, indicating that the dominant bacterial flora was enriched in its rhizosphere microbes and played an important role in plant growth and development. These results lay a foundation for exploring the mechanism of interaction between C. sinensis cv. Shifocui and rhizosphere microorganisms and provide a research basis for the development and utilization of tea plant microbial resources. [ABSTRACT FROM AUTHOR]

While a lot is known about cytokinins (CKs) and their actions at the molecular and cellular levels in plants, much less is known about the function of CKs in other kingdoms such as fungi. CKs have been detected in a wide range of fungal species where they play roles ranging from enhancing the virulence of phytopathogens to fortifying plant growth when secreted from fungal symbionts. However, the role of CKs where they concern fungal physiology, apart from plant associations, remains largely uncharacterized. Profiling by UHPLC-HRMS/MS (ultrahigh-performance liquid chromatography–high-resolution tandem mass spectrometry) revealed that Pleurotus ostreatus (oyster mushroom) produces CKs in vitro in both liquid and solid cultures. During fungal growth, CK profiling patterns were consistent with previous suggestions that tRNA degradation products might play a role in the physiological development of fungi. It confirms that those products are CKs that act as fungal growth regulators. Moreover, P. ostreatus was shown to respond to exogenous applications of aromatic and isoprenoid CKs, and their effects were dependent on the dose and CK type in a biphasic manner consistent with hormone action. N6-benzyladenine (BAP), kinetin (KIN), N6-isopentenyladenine (iP), and trans-zeatin (tZ) bioassays all revealed hormesis-type responses. Accordingly, at low doses, mycelium colony diameter, biomass accumulation, and changes in morphology were stimulated, whereas at high doses only inhibitory effects were observed. Thus, CKs may act as "mycohormones" and consequently have potential for applications in fungal agriculture and medicinal compound production. [ABSTRACT FROM AUTHOR]

Various environmental conditions influence the characteristics of plant communities within wetlands. Although the influence of key environmental factors on plant community traits within specific types of wetland ecosystems has been studied extensively, how they regulate plant communities across marsh wetland types remains poorly understood. We examined how environmental conditions influence plant communities in marsh wetlands along the lower Tumen River in northeastern China. We collected and analyzed data on the plant community characteristics (species, height, and coverage), soil physicochemical properties (organic carbon, inorganic nitrogen, and sulfur), and climatic and topographic factors (temperature, precipitation, and elevation) of 56 distinct marsh plots (29 herbaceous, 14 shrub, and 13 forested marshes) to understand how these variables correlate with plant community characteristics across marsh types. The wetland plant diversity varied, with the lowest, intermediate, and highest diversity occurring in herbaceous, shrub, and forested marshes, respectively. Climate, topography, and soil properties had crucial influences on plant diversity and biomass. Structural equation modeling showed that, in herbaceous marshes, plant biomass was primarily determined by soil and plant diversity, with climate exerting an indirect effect. In shrub marshes, soil, climate, and plant diversity directly influenced biomass. In forest marshes, soil and plant diversity directly affected biomass, whereas climate and topography had indirect effects. These findings highlight the complex interactions among environmental factors across marsh ecosystems and their influence mechanisms on biomass, aiding in formulating effective conservation and restoration strategies for marsh wetland ecosystems. [ABSTRACT FROM AUTHOR]

How different stress responses by male and female plants are influenced by interactions with rhizosphere microbes remains unclear. In this study, we employed poplar as a dioecious model plant and quantified biotic associations between microorganisms to explore the relationship between microbial associations and plant adaptation. We propose a health index (HI) to comprehensively characterize the physiological characteristics and adaptive capacity of plants under stress. It was found that male poplars demonstrated higher salt stress tolerance than females, and root‐secreted citric acid was significantly higher in the rhizospheres of male poplars. Positive biotic association among bacteria increased poplar HI significantly under salt stress, while fungal and cross‐domain biotic association (bacteria–fungi) did not. We further identified a keystone bacterial taxon regulating bacterial biotic association, ASV_22706, which was itself regulated by citric acid and significantly positively correlated with host HI. The abundance of keystone fungal taxa was positively correlated with HI of male poplars and negatively correlated with HI of female poplars. Compared with female poplars, male poplars enriched more prebiotics and probiotics under stress. This work primarily reveals the relationship between adaptation differences and microbial interactions in dioecious plants, which suggests a microbial approach to improve plant adaptability to stress conditions. [ABSTRACT FROM AUTHOR]

Plants are in intimate association with taxonomically structured microbial communities called the plant microbiota. There is growing evidence that the plant microbiota contributes to the holistic performance and general health of plants, especially under unfavorable situations. Despite the attached benefits, surprisingly, the plant microbiota in nature also includes potentially pathogenic strains, signifying that the plant hosts have tight control over these microbes. Despite the conceivable role of plant immunity in regulating its microbiota, we lack a complete understanding of its role in governing the assembly, maintenance, and function of the plant microbiota. Here, we highlight the recent progress on the mechanistic relevance of host immunity in orchestrating plant‐microbiota dialogues and discuss the pluses and perils of these microbial assemblies. [ABSTRACT FROM AUTHOR]

Alpine ecosystems, highly sensitive to climate change, are experiencing shifts in species ranges and community structure. These changes are driven by a complex interplay of climatic and environmental factors, land use changes, geomorphological dynamics, and species interactions, which can often lead to contrasted and sometimes unexpected dynamics. Historical records provide a valuable opportunity to capture these complexities by revealing long‐term changes, opening a gateway to hypothesise about the key underlying processes. We investigated changes in the floristic composition of subalpine to nival vegetation communities by resurveying a period of 70 years. To understand vegetation patterns, we (i) resampled vegetation at plot level and remapped the area, (ii) analysed the role of driving climate, environmental, and land use factors on vegetation distribution and vascular plant species richness, and (iii) modelled plant‐plant interactions from community data. The results reveal that vegetation cover patterns were strongly influenced by local climate and soil properties. The species richness is also influenced by the livestock density and the flat morphology. It should be noted that climate change caused wetland habitats to become drier and accelerated secondary succession through upward migration and range‐infilling processes. Furthermore, a trend towards eutrophication was observed. The results suggested that certain plant communities, particularly those found in snowbeds, were more vulnerable to environmental changes that have occurred over the past 70 years. Synthesis: This study highlighted the complexity of vegetation dynamics. In addition to thermophilisation and aridification, changes in land use affect species composition, species richness, and vegetation cover. Substrate conditions also play an important role. [ABSTRACT FROM AUTHOR]

Effective disease management hinges on an accurate understanding of the ecological and epidemiological underpinnings of the pathosystem. New epidemics may prompt consideration of whether knowledge gaps or changes to the pathosystem warrant revision of management strategies. Pierce's disease of grapevines is highly episodic in coastal Northern California vineyards, with modest incidence in most years punctuated by occasionally severe epidemics.To better understand what was driving a developing epidemic in the region, we revaluated what is known about the ecology and epidemiological role of the dominant vector, the blue-green sharpshooter Graphocephala atropunctata. We monitored vector spatiotemporal dynamics at 32 vineyards over three years, surveyed plant community composition in the adjacent habitat to understand its link to vector recruitment, and quantified patterns of natural infectivity for the pathogen Xylella fastidiosa. Overall, the results were consistent with past studies of G. atropunctata ecology. For example, the scale of dispersal from source habitat and seasonal patterns in activity were generally similar to those documented in prior studies. The results also confirmed the influence of adjacent plant community composition on G. atropunctata activity in vineyards, and the role of riparian habitat and select plant taxa as vector sources. Nonetheless, further consideration of the epidemiological significance of certain features of the pathosystem may be warranted, especially those related to seasonality in X. fastidiosa infection in vectors. A marked increase in infected G. atropunctata late in the season likely reflects pathogen acquisition from infected grapevines, which may have implications for disease management strategies. [ABSTRACT FROM AUTHOR]

Global warming is exhibiting a seasonal trend, while different seasons have different warming variations. However, the impact of seasonal warming on plants remains unclear. This study employed Open Top Chambers (OTCs) to simulate future seasonal warming scenarios in alpine meadow. The study examined plant community dynamics following long‐term seasonal warming. The transcriptional and physiological responses of two dominant species (Kobresia pygmaea and Stipa purpurea) were examined. Results suggest that seasonal warming effects are correlated with both the duration of warming and the season which warming occurs. A long annual warming duration, especially growing season warming, made plants confront various stresses. K. pygmaea adopted a stress‐avoidance strategy, showing a negative response, and leading to population decline or disappearance. This kind of dieback had also been observed in other Cyperaceae species. Meanwhile, due to positive responses, S. purpurea adopted a stress‐tolerance strategy and overcame the impact of warming, partially gained the dominance over Cyperaceae species. Overall vegetation coverage and plant community diversity decreased over the years. These results reveal the impact of seasonal warming to plants, explaining the reasons for changes in plant communities under seasonal warming and providing new insights for future plant conservation under seasonal warming. Significance Statement: Seasonal warming exerts distinct effects on plant communities compared to year‐round warming. This study demonstrates that warming during the growing season, particularly in summer and autumn, imposes significant stress on alpine meadow plants. The negative response of Cyperaceae species emerges as a critical factor driving community degradation under seasonal warming. These findings advance our understanding of the ecological impacts of seasonal warming and elucidate potential mechanisms underlying plant community decline. They also provide a theoretical foundation for grassland management and conservation strategies in the context of future global seasonal warming scenarios. [ABSTRACT FROM AUTHOR]

In Lotka–Volterra community models, given a set of biotic interactions, recent approaches have analysed the probability of finding a set of species intrinsic growth rates (representing intraspecific demographic features) that will allow coexistence. Several metrics have been used to quantify the fragility of coexistence in the face of variations in those intrinsic growth rates (representing environmental perturbations), thus probing a notion of 'distance' to the edge of coexistence of the community. Here, for any set of interacting species, we derive an analytical expression for the whole distribution of distances to the edge of their coexistence. Remarkably, this distribution is entirely driven by (at most) two characteristic distances that can be directly computed from the matrix of species interactions. We illustrate on data from experimental plant communities that our results offer new ways to study the contextual role of species in maintaining coexistence, and allow us to quantify the extent to which intraspecific features and biotic interactions combine favorably (making coexistence more robust than expected), or unfavourably (making coexistence less robust than expected). Our work synthesizes different study of coexistence and proposes new, easily calculable metrics to enrich research on community persistence in the face of environmental disturbances. [ABSTRACT FROM AUTHOR]

Plant pathogens are important for community assembly and ecosystem functioning and respond to a variety of abiotic and biotic factors, which may change along elevational gradients. Thus, elevational gradients are a valuable model system for exploring how environmental, plant community and soil factors influence pathogen communities. Yet, how these factors influence pathogens in natural ecosystems remains poorly understood. We examined the dynamics of plant fungal pathogens along elevational gradients, as well as the mechanisms shaping these dynamics, by combining a field survey on the Tibetan Plateau with a global meta‐analysis. In the field survey, increasing elevation was associated with a decrease in soil fungal pathogen richness but not in foliar fungal disease symptoms. Elevation was primarily related to soil fungal pathogen richness through abiotic factors, whereas no association was found between elevation and foliar fungal diseases. The meta‐analysis confirmed the generality of our field survey results: elevation was associated with a decrease in soil fungal pathogen richness, but it had no consistent relationship with foliar fungal diseases or pathogens. Thus, above‐ and belowground plant pathogen communities showed distinct elevational patterns, providing new insights into underlying mechanisms. [ABSTRACT FROM AUTHOR]

Both environmental and edaphic variables play an important role in the structure, composition, and distribution of plant communities. In the present study, we aimed to investigate the major plant associations along the altitudinal gradient and the effects of various topographic and edaphic variables on the distribution of vegetation in the Sultan Khail Valley in the Hindu Kush range of Pakistan. The data was collected between 2017 and 2019. For field data collection, the valley was divided into various ecological zones based on altitude, aspect, physiognomy, and geographical coordinates. Two hundred vineyards were established for the data collection. The canopy cover and the number of vascular plant species were determined using the Braun-Blanquet scale. Soil samples were collected and analyzed for various physicochemical properties. In the JUICE host program, the modified Two Way Indicator Species Analysis (TWINSPAN) was used to do a multivariate analysis of vegetative data. To emphasize diagnostic, constant, and dominant species, a threshold of 40% was set for the fidelity, frequency, and cover of species in each association. For vegetation ordination, DCA ordination was performed using R Project version 3.6.1. Modified TWINSPAN results in the formation of 5 associations of vegetation: i. Abies-Picea-Sibbaldia Association (APS), ii. Pinus-Wikstroemia-Galium association (PWG), iii. Ajuga-Artemisia-Quercus association (AAQ), iv. Cotoneaster-Quercus-Indigofera association (CQI), and v. Conyza-Juglans-Dicliptera association (CJD). The results of DCA ordering showed that elevation, slope angle, clay content (%), potassium, and pH of the soil were the most important factors for the distribution of species in different associations in the Sultan Khail Valley of Pakistan. The soils in the study area were loamy, silty-loamy to loamy-sandy, alkaline to acidic. and contained varying amounts of lime, organic matter, as well as nitrogen, phosphorus, and potassium. In conclusion, the study successfully employed advanced multivariate analysis techniques to uncover the complex relationship between vegetation diversity and environmental conditions in the Sultan Khail Valley of Pakistan, a part of the Hindu Kush Range. The detailed analysis of the study revealed the complex interplay of numerous environmental variables and provided important insights for the conservation and sustainable management of this ecologically important region. [ABSTRACT FROM AUTHOR]

Topography has an important influence on plant–soil relationships. However, research on plant–soil relationships in alpine grassland at the slope aspect and slope position scales is currently inadequate. In this paper, based on the topographic and geomorphological characteristics of the study area, alpine grassland with typical slope aspect and slope position conditions was selected as the research object. Through field investigations and laboratory research to reveal how the characteristics of the alpine grassland plant community and soil factors respond to changes in topography. The results show: Slope aspect and slope position changes significantly affect alpine grassland plant communities and soil properties. In terms of the dominant species in plant communities, the sunny slopes were dominated by Poaceae and the shady slopes were dominated by Polygonaceae. Plant community characterization variables showed a decreasing trend from shady to sunny slopes and bottom to top. The soil factors showed significant differences among the six types of topography (p < 0.05), and the magnitude order in different slope aspects and positions was basically shady slope > sunny slope and bottom > middle and top. Correlation analysis showed that there were good correlations between soil organic carbon (SOC), soil water content (SWC), total nitrogen (TN), pH, and plant community characteristics in alpine grassland. In addition, redundancy analyses (RDA) indicated that the divergence in plant community characteristics was primarily driven by the change difference in SOC along topographic gradients. Our findings may provide a scientific basis for the restoration and utilization of alpine grassland vegetation and the evaluation of the ecological environment in this region. [ABSTRACT FROM AUTHOR]

Paleoenvironmental insights gleaned from geological history are profoundly important for the discovery and exploitation of mineral resources. In China's Bohai Bay Basin, the Kongdian Formation represents the principal oil-bearing stratum from the Eocene Epoch. However, a comprehensive understanding of its paleoenvironmental evolution and stratigraphic division has been hindered by the paucity of paleontological data. To address this gap, three sedimentary cores were meticulously collected from the southern extremity of the Liaoxi Uplift within the Bohai Bay. These cores underwent a thorough sporopollen-algae analysis to elucidate their stratigraphic division and to reconstruct the associated paleoenvironmental conditions. The analysis yielded the identification of three distinct sporopollen-algae assemblages of the regional Kongdian Formation: (1) The assemblage of Divisisporites longilaesuratus-Betulaepollenites-Tiliaepollenites microreticulatus is indicative of the lower submember of the Kongdian Formation Ek2; (2) The assemblage of Polypodiaceaesporites-Alnipollenites indicates the upper submember of the Ek2; (3) The assemblage of Pterisisporites undulatus-Taxodiaceaepollenites-Ephedripites corresponds to the Kongdian Formation Ek1. These assemblages reflect a significant evolutionary trajectory of the regional plant communities throughout the Kongdian Formation. Initially, there were evergreen arbor-shrub mixed forests, which transitioned to green algae-herb-evergreen broadleaved biota and finally evolved into evergreen conifer-shrub mixed forests. This botanical evolution mirrors shifts in the paleoclimate, which experienced a progression from conditions of high temperature and high humidity through a phase of warm, semi-humid environments to eventually high temperature and semi-arid conditions. [ABSTRACT FROM AUTHOR]

Invasive species are increasingly spreading, particularly in rangeland ecosystems. It is essential to evaluate the effectiveness of different methods for controlling invasive plants in these ecosystems. This study aimed to investigate the effects of three strategies-21-year grazing exclusion (21-YES), mowing-grazing in rotation in alternate years (MGRS), and moderate grazing (MGS)- on the change in cover, density, and biomass of Leucanthemum vulgare Lam. (Ox-eye Daisy=OED) and the plant community. To accomplish this, three sites selected for each treatment. In 2021, 270 vegetation plots were sampled using a random systematic method. Subsequently, we recorded the density and canopy cover of all growth forms (forbs, grasses, and ferns), the OED biomass, and the ground cover. The results indicated that MGS reduced OED density, OED canopy, and OED biomass. Furthermore, this strategy demonstrated the highest density and canopy cover of the plant community (including total, forbs, grasses, and ferns). Additionally, the strongest correlation was observed between the total canopy and the OED density (R2=−0.91, −0.95, −0.94 in 21-YES, MGRS, and MGS, respectively), as well as between the total canopy and the OED canopy (R2=−0.51, −0.98, −0.97 in 21-YES, MGRS, and MGS, respectively). The MGS led to an increase in diversity indices. In general, the grazing strategy has proven to be effective in controlling the spread of invasive OED and has also resulted in an increase in canopy cover, density, and diversity indices of the plant community. The study highlights the importance of ongoing management efforts to control invasive species, with moderate grazing potentially serving as a more practical, culturally accepted, and cost-effective short-term control strategy for widespread rangeland weed infestations. [ABSTRACT FROM AUTHOR]

Aridity, edaphic variables and livestock grazing are major drivers of plant community composition across arid rangelands. Accumulated knowledge exists on the impact of each driver on community composition. Although previous studies have demonstrated changes in direct grazing impacts on ecosystem functions and community composition at different aridity levels, ranging from mesic to arid grasslands, whether a regional‐scale and continuous spatial pattern of plant compositional change along a gradient of aridity or edaphic variables is altered by grazing remains controversial. We compared the determinants and patterns of compositional changes with/without highly intensive grazing in the semi‐arid/arid regions of Mongolia. The compositional changes based on Bray–Curtis dissimilarity were investigated using generalized dissimilarity modeling, including geographic distance, aridity, soil pH and soil texture as independent variables. Aridity consistently had a significant impact on community composition, regardless of the region and presence/absence of grazing. However, a difference in response patterns was observed between the regions. The compositional change was steeper at the upper (drier) limit of aridity than at the lower limit in the arid region. This pattern indicates the vulnerability of plant communities to aridity shifts owing to future climate change, especially in the desert steppe of Mongolia, although the predictions of shifts in aridity are not accurate. In addition, regardless of the region, the effects of soil pH on the community composition were eliminated by the presence of grazing. Grazing may homogenize community composition by not reflecting the spatial heterogeneity of soil pH or nutrient availability via selective herbivory. Despite the potential indirect impacts of climate change on community composition via soil pH, the observations for only plant communities under intensive grazing might overlook regional biodiversity changes caused by global change drivers. [ABSTRACT FROM AUTHOR]

In this study, we provide an ~47.0‐kyr mercury (Hg) deposition record derived from a lacustrine sedimentary sequence in Dahu swamp in the eastern Nanling Mountains, China. The results indicate that organic matter (OM) input played a role in Hg accumulation, whereas the contribution of inorganic weathering detritus had a negligible impact. On the other hand, evolution of the plant community and wildfire events were also important factors affecting Hg accumulation. Compared to arboreal plants, lower (herbs and ferns) plants had stronger absorption and enrichment ability for Hg thus favoring enhanced Hg accumulation in the sediments. We therefore infer that Hg deposition in Dahu sediments was greatly controlled by changes in climatic conditions. Relatively dry and cold climatic conditions, which resulted in reduced arboreal plant communities and increased lower plants, would favor an increased Hg accumulation rate; furthermore, dry conditions may cause more wildfire events thus leading to enhanced release of Hg into the environment and increased contribution of Hg to the sediments, whereas relatively wet and warm conditions would result in the opposite situation. The record of Hg deposition demonstrates a synchronous orbital‐scale variation trend with the intensity of the East Asian summer monsoon. Period analysis reveals several millennial‐ and centennial‐scale cycles similar to solar insolation, together with several millennial events of increased Hg concentration and accumulation rate, which coincided with the corresponding Heinrich events, suggesting joint impacts of solar irradiation and the action of melting water as well as changes in zonal atmospheric circulation on Hg accumulation in Dahu sediments. [ABSTRACT FROM AUTHOR]

Climate change is causing marked shifts to historic environmental regimes, including increases in precipitation events (droughts and highly wet periods). Relative to droughts, the impacts of wet events have received less attention, despite heavy rainfall events increasing over the past century. Further, impacts of wet and dry events are often evaluated independently; yet, to persist and maintain their ecosystem functions, plant communities must be resilient to both precipitation events. This is particularly critical because while community properties can modulate the resilience (resistance, recovery, and invariability) of ecosystem functions to precipitation events, community properties can also respond to precipitation events. As a result, community responses to wet and dry years may impact the community's resilience to future events. Using two decades (2000–2020) of annual net primary productivity data from early successional grassland communities, we evaluated the plant community properties regulating primary productivity resistance and recovery to contrasting precipitation events and invariability (i.e. long‐term stability). We then explored how resilience‐modulating community properties responded to precipitation. We found that community properties—specifically, evenness, dominant species (Solidago altissima) relative abundance, and species richness—strongly regulate productivity resistance to drought and predict productivity invariability and tended to promote resistance to wet years. These community properties also responded to both wet and dry precipitation extremes and exhibited lagged responses that lasted into the next growing season. We infer that these connections between precipitation events, community properties, and resilience may lead to feedbacks impacting a plant community's resilience to subsequent precipitation events. Synthesis. By exploring the impacts of both drought and wet extremes, our work uncovers how precipitation events, which may not necessarily impact productivity directly, could still cryptically influence resilience via shifts in resilience‐promoting properties of the plant community. We conclude that these precipitation event‐driven community shifts may feedback to impact long‐term productivity resilience under climate change. [ABSTRACT FROM AUTHOR]

This study evaluates the growth, survival pressures, and community dynamics of Barringtonia racemosa (L.) Spreng. populations in Jiulong Mountain and Suixi County, Guangdong Province. Six distinct plant communities were identified, with human disturbances significantly disrupting natural succession processes. The population in Jiulong Mountain, particularly within the Talipariti tiliaceum-B. racemosa community (JLS-T), experienced higher survival pressures compared to Suixi County. Interspecific competition varied, with species like Derris trifoliata, T. tiliaceum, and invasives such as Ipomoea cairica and Mikania micrantha exerting substantial pressure on B. racemosa. Analysis of 234 B. racemosa individuals revealed significant correlations between diameter at breast height (DBH), plant height, and age structure distribution, with a linear relationship between DBH and height underscoring their relevance in understanding wood volume, biomass, and stand structure. Survival pressures were inversely related to DBH, indicating reduced competition as trees matured. Growth patterns exhibited an age-dependent plateau in height, potentially influenced by environmental and anthropogenic factors. Management strategies should prioritize the growth of individuals with DBH less than 5 cm (age classes I ~ II). These findings underscore the need for targeted conservation efforts to protect B. racemosa communities and sustain wetland ecosystems. [ABSTRACT FROM AUTHOR]

Summary Affecting biodiversity, plants with larger genome sizes (GS) may be restricted in nutrient‐poor conditions. This pattern has been attributed to their greater cellular nitrogen (N) and phosphorus (P) investments and hypothesized nutrient–investment tradeoffs between cell synthesis and physiological attributes associated with growth. However, the influence of GS on cell size and functioning may also contribute to GS‐dependent growth responses to nutrients. To test whether and how GS is associated with cellular nutrient, stomata, and/or physiological attributes, we examined > 500 forbs and grasses from seven grassland sites conducting a long‐term N and P fertilization experiment. Larger GS plants had increased cellular nutrient contents and larger, but fewer stomata than smaller GS plants. Larger GS grasses (but not forbs) also had lower photosynthetic rates and water‐use efficiencies. However, nutrients had no direct effect on GS‐dependent physiological attributes and GS‐dependent physiological changes likely arise from how GS influences cells. At the driest sites, large GS grasses displayed high water‐use efficiency mostly because transpiration was reduced relative to photosynthesis in these conditions. We suggest that climatic conditions and GS‐associated cell traits that modify physiological responses, rather than resource–investment tradeoffs, largely explain GS‐dependent growth responses to nutrients (especially for grasses). [ABSTRACT FROM AUTHOR]

Background: The changes of microbial community on tobacco leaves are affected by several factors during fermentation. However, the relative contribution of different factors in determining microbial community is not clear. This study investigated the effects of fermentation time (fermentation for 0, 3, 6, 9 and 12 months), leaf position (middle and top tobacco leaves) and fermentation site (Longyan and Xiamen warehouses) on bacterial community of tobacco leaves using 16 S rDNA sequencing. Results: The results demonstrated that fermentation time had a much stronger impact on bacterial diversity, composition, co-occurrence network and functional profiles than leaf position and fermentation site. With the fermentation progressed, the difference of bacterial community between middle and top tobacco leaves was gradually reduced or even disappeared. The bacterial community diversity and network complexity at three, six and nine months of fermentation were significantly lower than those at fermentation initiation. Specific bacterial genera with desired functions were recruited at different fermentation stages, such as Terribacillus, Pantoea and Franconibacter at three or six months of fermentation and Pseudomonas at nine months of fermentation. The recruited microorganisms would form biofilms on tobacco leaves and compete for polysaccharide or protein substances to accelerate the degradation of tobacco macromolecular substances. Conclusions: In conclusion, fermentation time was an important factor in determining the composition and function of microbial community on tobacco leaves during the fermentation process. [ABSTRACT FROM AUTHOR]

Recently, attention has been shifting toward the perspective of the existence of plants and microbes as a functioning ecological unit. However, studies highlighting the impacts of the microbial community on plant health are still limited. In this study, fungal community (mycobiome) of leaf, root, and soil of symptomatic leaf-spot diseased (SS) oil palm were compared against asymptomatic (AS) trees using ITS2 rRNA gene metabarcoding. A total of 3,435,417 high-quality sequences were obtained from 29 samples investigated. Out of the 14 phyla identified, Ascomycota and Basidiomycota were the most dominant accounting for 94.2 and 4.7% of the total counts in AS, and 75 and 21.2% in SS, respectively. Neopestalotiopsis is the most abundant genus for AS representing 8.0% of the identified amplicons compared to 2.0% in SS while Peniophora is the most abundant with 8.6% of the identified amplicons for SS compared to 0.1% in AS. The biomarker discovery algorithm LEfSe revealed different taxa signatures for the sample categories, particularly soil samples from asymptomatic trees, which were the most enriched. Network analysis revealed high modularity across all groups, except in root samples. Additionally, a large proportion of the identified keystone species consisted of rare taxa, suggesting potential role in ecosystem functions. Surprisingly both AS and SS leaf samples shared taxa previously associated with oil palm leaf spot disease. The significant abundance of Trichoderma asperellum in the asymptomatic root samples could be further explored as a potential biocontrol agent against oil palm disease. [ABSTRACT FROM AUTHOR]

Precipitation distribution during the growing season and interannual precipitation variation may have significant impacts on grassland ecosystem productivity at the site level. To explore the effect of the distribution of precipitation on plant communities in the Inner Mongolian desert steppe dominated by Stipa breviflora, we analyzed monthly precipitation patterns during the growing season (May–October) over the past 60 years (1961–2020) and identified four major precipitation distribution patterns. These included the concentrated precipitation during July (TΛ7), August (TΛ8), and during the early and late growth stages. However, with precipitation being scarce during the boom (TM), the distribution resembled a normal distribution (T∩). Field experiments simulating the four distributions were conducted from May to October 2021. The results showed that the effects of the distribution of precipitation on plant species, diversity, and abundance were not significant; only the Pielou evenness showed a significant effect after July. The total above-ground net primary productivity (ANPP) of TΛ7 was 55.4% higher than those of the other three patterns, whereas the differences among the other three precipitation distributions were not significant. The annual forb Neopallasia pectinate was the primary contributor to the increased ANPP of TΛ7. These results suggest that the S. breviflora desert steppe achieved maximum productivity when the precipitation reached 41.6% of the annual average during July and satisfied the basic plant growth requirements during other months. This study emphasizes the implementation of management measures (irrigation or artificial precipitation) for maximizing forage yield and forecasting the plant composition in desert steppes. [ABSTRACT FROM AUTHOR]

The assessment of fire effects in Aleppo pine forests is crucial for guiding the recovery of burnt areas. This study presents a methodology using UAV-LiDAR data to quantify malleability and elasticity in four burnt areas (1970, 1995, 2008 and 2015) through the statistical analysis of different metrics related to height structure and diversity (Height mean, 99th percentile and Coefficient of Variation), coverage, relative shape and distribution strata (Canopy Cover, Canopy Relief Ratio and Strata Percent Coverage), and canopy complexity (Profile Area and Profile Area Change). In general terms, malleability decreases over time in forest ecosystems that have been affected by wildfires, whereas elasticity is higher than what has been determined in previous studies. However, a particular specificity has been detected from the 1995 fire, so we can assume that there are other situational factors that may be affecting ecosystem resilience. LiDAR metrics and uni-temporal sampling between burnt sectors and control aids are used to understand community resilience and to identify the different recovery stages in P. halepensis forests. [ABSTRACT FROM AUTHOR]

ABSTRACT Powdery mildew (PM), caused by the biotrophic fungus Podospharea leucotricha, is a major threat to apple production. Plant–plant communication (PPC) is a crucial strategy for plant communities to enhance their defence against pathogens. The interconversion of methyl salicylate (MeSA) and salicylic acid (SA) is critical for PPC regulation, but the mechanism of MeSA‐mediated PPC is not fully understood. This study reveals a significant increase in SA and MeSA levels in neighbouring plants (receivers) following PM attack on emitter plants, activating defence responses in receivers. Notably, the expression of WRKY1, a previously characterized transcription factor, was upregulated in receivers, implicating its role in defence response modulation. WRKY1 was found to promote SA accumulation and enhance PM resistance in receivers. Importantly, WRKY1 positively regulates the expression of SABP2a, which catalysers MeSA to SA conversion, and negatively regulates SAMT1a, which functions in the reverse reaction. Consequently, WRKY1 facilitates the conversion of MeSA to SA in receivers, preventing its reversion and sustaining elevated SA levels. Collectively, our findings clarify the role of WRKY1 in enhancing the defence response to PM in receivers. [ABSTRACT FROM AUTHOR]

Mycorrhizal associations drive plant community diversity and ecosystem functions. Arbuscular mycorrhiza (AM) and ectomycorrhiza (EcM) are two widespread mycorrhizal types and are thought to differentially affect plant diversity and productivity by nutrient acquisition and plant–soil feedback. However, it remains unclear how the mixture of two mycorrhizal types influences tree diversity, forest biomass, and their relationship at large spatial scales. Here, we explored these issues using data from 1247 plots (600 m2 for each) across China's natural forests located mostly in temperate and subtropical regions. Both AM‐dominated and EcM‐dominated forests show relatively lower tree species richness and stand biomass, whereas forests with the mixture of mycorrhizal strategies sustain more tree species and higher biomass. Interestingly, the positive effect of tree diversity on biomass is stronger in forests with low (≤50%) than high AM tree proportion (>50%), reflecting a shift from the complementarity effect to functional redundancy with increasing AM trees. Our findings suggest that mycorrhizal dominance influences tree diversity and richness–biomass relationship in forest ecosystems. [ABSTRACT FROM AUTHOR]

Tree plantations are considered as a solution to reduce the impacts of climate change and can enhance biodiversity. Consequently, many tree planting schemes around the world have been started to achieve these dual objectives. However, many of these tree plantations are being implemented without proper design or post‐plantation management, often overlooking potential long‐term effects on biodiversity. Therefore, it is essential to identify which aspects of tree plantations can negatively impact biodiversity. Such knowledge is vital to design new plantations and manage existing ones, such that they do not pose threats or additional costs to the conservation of natural ecosystems. To this end, we conducted an observational study in the Mediterranean heathland habitat of the southwestern Iberian Peninsula. This treeless habitat, locally known as herriza, has been planted with pine trees until the onset of the 21st century. This historical tree plantation presents a unique natural experiment to assess the long‐term effect of tree cover, measured as canopy openness, on several community properties of plant, pollinators and their network of interactions. Our results reveal a strong positive relationship between canopy openness and floristic diversity and abundance. This means that, as we increase tree cover, plant diversity is reduced. We found this has consequences for pollinator diversity and plant–pollinator networks, the latter exhibiting declines in stability. Furthermore, we reveal the importance of woody blooming plants in comparison to non‐woody ones which, despite their greater importance for pollinators, they are the most impacted. These findings underscore the importance of tree cover for severely affecting multiple properties of plant–pollinator networks at different levels of organization. Overall, this knowledge indicates that high tree cover in plantations conducted 50 years ago is incompatible with maintaining and conserving plant–pollinator networks in natural treeless habitats, at least in the herriza. Actions that want to avoid negative long‐term effects of tree plantations on plant–pollinator communities should consider existing biodiversity before planting and refrain from achieving high tree cover values. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Climate and geological diversity have been proven to make an important contribution to biodiversity. Volcanic ecosystems often have a long geological history and diverse bedrock, thus shaping a variety of habitats. Understanding the relative importance and role of the contemporary climate and geological bedrock environment in volcanic biodiversity still needs further exploration. To address this knowledge gap, we investigated the patterns of plant diversity and phylogenetic structure at the community level in Qiniangshan Mountain, while also exploring the relationship between biodiversity and regional environmental factors (e.g., climate and bedrock types). In the Qiniangshan Mountain plant communities, species richness is higher at mid-to-high elevations. Montane communities exhibit higher species richness compared to coastal communities. There are significant differences in species richness among plant communities on different bedrock, with the highest species richness found on pyroclastic lava. Bedrock, along with climate factors related to energy and precipitation, collectively influence the patterns of species richness in plant communities. The Net Relatedness Index (NRI) of plant communities is influenced by climate factors and aspects, while the Nearest Taxon Index (NTI) is affected by both bedrock and climate factors. The Phylogenetic Diversity Index (PDI) is primarily related to climate factors. Climate and bedrock collectively influence the patterns of species richness and phylogenetic structure within Qiniangshan Mountain's plant communities. These findings highlight the profound impact of both climate and bedrock on montane vegetation and community biodiversity. [ABSTRACT FROM AUTHOR]

The emergence of β‐diversity of plant‐associated fungi across diverse coexisting host plant species in natural habitats is intricately linked to specific community assembly processes. Despite this, the relative contributions of various assembly processes to the observed β‐diversity patterns, as well as the influence of plant traits on these contributions, are still poorly understood. Here, we investigated the leaf/root‐associated fungal communities across nine coexisting dominant herbaceous perennials in a temperate grassland that had undergone a 17‐year mowing treatment. We elucidated the β‐diversity components and community assembly processes of these fungal communities. Furthermore, we explored relationships between leaf/root functional trait variations and fungal community assemblies. We tested the following hypotheses: (1) both species turnover and nestedness are important components of the fungal β‐diversity, with selection predominating in the fungal community assemblies; (2) mowing enhances the contributions of nestedness/selection; (3) plant trait variations significantly affect the fungal community assembly processes. Unexpectedly, our findings demonstrated a predominance of leaf/root fungal species turnover among coexisting plant hosts, contrasting with nestedness. Moreover, dispersal limitation emerged as the primary factor shaping fungal community assemblies, rather than selection processes. Although mowing significantly inhibited plant growth, its effects on the overall patterns of fungal assemblages were limited. We further observed that higher degrees of plant trait variations were primarily linked to stronger dispersal limitation, with a relatively weaker influence on heterogeneous selection. Additionally, the impact of plant traits on the selection process of root‐associated fungi was more pronounced compared to that of leaf‐associated fungi. Synthesis. Our study reveals that the β‐diversity of fungi associated with coexisting plants in natural grasslands is primarily attributed to fungal species replacement rather than gain‐and‐loss dynamics among these plants. Concurrently, this observed pattern is largely governed by dispersal limitation as opposed to selection. We propose that the primary mechanism through which plant hosts and their traits influence the structures of associated fungal communities is by limiting fungal dispersal, while niche differentiation among fungal taxa plays a secondary role. These findings offer a mechanistic insight into the assemblies of plant mycobiomes and further elucidate the plant‐mycobiome relationships within complex plant communities. [ABSTRACT FROM AUTHOR]