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Background: Vegetation science research has been conducted for approximately 200 years; however, until now there has not been a unified classification principle or system that was acceptable to vegetation scientists. To facilitate the development of vegetation science and its applications in natural conservation, a unified vegetation classification system is urgently required. Here we propose a unified eco‐physiognomic‐floristic vegetation classification system (EcoFloVCS) that combines eco‐physiognomic and floristic characteristic classification systems. Methods: Under the EcoFloVCS, plant communities are considered to have six key components (species composition, structure, habitat, development, locality, and function). Six associated characteristics are derived from these six components (dominant species, diagnostic species, physiognomy, distribution patterns, dynamics, and disturbance processes). These characteristics are used as the basis for community classification. Results and Conclusions: The high‐level units of this system agree with the UNESCO system, whereas the middle‐ and low‐level units correspond to the Braun‐Blanquet classification system. Both are connected by a Division (Subformation) unit. Based on the EcoFloVCS, a vegetation system was constructed for the four highest units worldwide that included seven Formation Classes, 22 Formation Subclasses, 39 Formation Groups, and 119 Formations. We assume that vegetation science will benefit from our unified EcoFloVCS through comparing and understanding community structures and functions on a global scale. [ABSTRACT FROM AUTHOR]

Question: We address the following questions: (1) which are the main plant communities in montane grasslands in central Argentina; (2) do those communities differ in terms of floristic composition, endemisms, chorotypes and life forms; and (3) which are the major environmental variables (climatic, topographic and edaphic) associated with the heterogeneity of the vegetation? Location: Pampean Mountains (Sierras Pampeanas), Córdoba Province, central Argentina, an area of ca. 37,000 km2. Methods: The survey was based on a data set comprising 746 relevés and 822 vascular plant species, collected in accordance with the Braun‐Blanquet sampling method. The data were classified using the hierarchical ISOmetric feature mapping and Partitioning Around Medoids, and ordinated through isometric feature mapping (ISOPAM). The environmental variables were related to the ISOPAM ordination. Results: The ISOPAM classification identified two clusters, five vegetation types and 17 plant communities, which were distributed across different elevations. There were notable differences in the diagnostic species, average percentages of endemic species, chorotypes and life forms among the various vegetation types and plant communities. The primary gradient in grassland vegetation was found to be associated with elevation and related climatic variables. Conclusions: The study provides valuable insights into the montane grasslands of the Sierras Pampeanas in central Argentina. It presents a comprehensive classification of the region's grasslands, including tall tussock grasslands, humid grasslands, stony grasslands, and grasslands with scattered shrubs and trees. Each recognized unit is distinguished by diagnostic species and a distinct floristic composition. Our findings emphasize a significant division between grasslands at higher elevation, abundant in Andean species, and Piedmont and shrubby grasslands at lower elevations, characterized by a higher prevalence of Chacoan and other Neotropical species. Grassland vegetation in other regions of the Sierras Pampeanas remains poorly studied, requiring additional research to determine the syntaxonomic position of this vegetation. [ABSTRACT FROM AUTHOR]

Aims: Effective prevention and management of biological invasions are crucial. One promising approach involves introducing biochar to invaded plant communities to modify interspecific relationships among invasive and native plants, ultimately aiding in the suppression of invasive species. This study aimed to explore the effects of invasive‐plant biochar on an established invaded plant community. Location: Tianjin coastal saline‐alkaline wetland, China (38°46′ N, 117°34′ E). Methods: Invaded plant communities were established using soils from an Amaranthus palmeri‐invaded wetland with an intact seed bank, incorporating invasive‐plant biochar derived from A. palmeri and Spartina alterniflora into the soil at 0%, 1%, 3%, and 5% addition rates (m/m). Plant above‐ground biomass, height, stem diameter, abundance, α/β‐diversity, niche breadth, and species co‐occurrence networks were analyzed. Results: The addition of invasive‐plant biochar significantly decreased the performance measures of the invaded plant community. The biochar addition rate had a more substantial impact on plant community structure than the type of biochar used. There was a decrease in the abundance of A. palmeri and an increase in native plants across most treatments, with S. alterniflora biochar exhibiting a more pronounced effect compared to A. palmeri biochar. Invasive‐plant biochar affected the niche breadth of A. palmeri and other dominant native species, particularly at higher addition rates, resulting in reduced niche overlap. At a 5% addition rate, A. palmeri and S. alterniflora biochar had contrasting effects on the complexity of interspecific relationships within the plant community. Phylogenetic β‐diversities were significantly correlated with the biochar addition rate and stochastic processes primarily governed plant community assembly across all treatments. Conclusions: Our findings underscore the potential of biochar derived from invasive plants to mitigate the impact of invasive species on saline‐alkaline wetland plant communities dominated by A. palmeri. This approach offers a promising avenue for managing biological invasions and restoring native plant species. [ABSTRACT FROM AUTHOR]

Questions: Plant communities have been shown to include several functional groups of species that may have contrasting responses to the effects of dominant neighbours, although potentially balancing at the community level. We aimed to assess the potential of species‐group vs community‐level responses of subordinate species to explain variation in the effects of the dominant shrub Artemisia sieberi on understorey species along a grazing intensity gradient in arid steppes of northeast Iran. We also aimed to assess whether species‐group responses help explain variation in community composition. Locations: An Artemisia steppe community in Golestan National Park (northeast Iran). Methods: We used the relative interaction index (RII) to quantify the effects of a shrub on the cover of the 12 most frequent subordinate species. We conducted a first principal component analysis (PCA) on species RII followed by cluster analysis to group species depending on their responses to the shrub, and a second PCA on subordinate species composition. Results: At the community level, subordinate species showed strong competition at the low grazing level, weak facilitation at the intermediate level and weak competition at the high grazing level; a unimodal pattern with a switch back to competition in extremely disturbed conditions that is inconsistent with ecological theories. However, species‐group analyses showed contrasting subordinate species responses, supporting either the decrease in competition with increasing disturbance scenario or the collapse of facilitation, but never a switch back to competition as predicted by recent facilitation theory along resource gradients. Moreover, these contrasting species‐group responses significantly explained community composition. Conclusions: Our study provides new evidence, along a grazing intensity gradient, that communities include different species groups with contrasting responses to dominant species. [ABSTRACT FROM AUTHOR]

Aim: Livestock production is among the main anthropogenic disturbances in seasonally dry tropical forests. However, its effects on plant functional composition in dry forests is poorly understood. Our goal was to analyze the variation in both functional composition and functional diversity of plant communities under goat grazing and at different ages of fallow in a tropical dry forest. Location: Brazilian dry forest (Caatinga) in Rio Grande do Norte State, northeastern Brazil. Methods: We measured the height, leaf area, and specific leaf area of all shrub‐tree and herbaceous species along a gradient of stocking rate, years of grazing, and age of fallow. Additionally, we quantified the foliar contents of nitrogen, phosphorus, and tannins in the tree shrub layer. We tested the effects of grazing and deforestation using linear mixed models. Results: Our findings suggest that the functional diversity of plant communities in the Caatinga is not altered when goat grazing and secondary succession are examined independently. However, the interaction of both factors has affected the functional diversity, particularly in the herbaceous layer. Although grazing influenced specific traits in the shrub‐tree layer, the overall functional diversity remained unaltered by grazing, succession, or their interaction. Conclusions: Grazing does not interfere with the natural succession process nor diminish the functional diversity of plant communities in the Caatinga. Therefore, with appropriate management, grazing can coexist with the conservation goals of the Caatinga. [ABSTRACT FROM AUTHOR]

Questions: The classification of plant communities is a well‐established practice in ecology. However, the factors that determine the distribution of common species and the extent of their dominance and overlap are still being debated. Large‐scale studies based on field data are of great interest in the face of biodiversity changes and climate change impacts. This research was designed to answer the following two questions: What are the dominant plant communities in the Patagonian steppes and how do they relate to environmental features, as measured by latitude, longitude, altitude, mean annual precipitation and mean temperature? What have been the recent changes in plant communities in terms of expansion and contraction of different types of communities? Location: Patagonian steppes (South America). Methods: We used a large database of species‐by‐species vegetation cover from 426 monitoring plots in the South American Patagonian steppes, surveyed between 2007 and 2019, with two different assessment dates at least 5 years apart. We applied archetypal analysis to identify different vegetation compositions at a regional scale (called floristic archetypes) and to track their changes over time. In addition, we analyzed the relationship between floristic archetypes and spatial and meteorological variables to assess the association between floristic composition and the environmental context. Results: Seven floristic archetypes were identified in the Patagonian steppes. The dominant and most widespread floristic archetype showed an expanding pattern in floristic trajectories and was positively associated with mean annual temperature. This floristic archetype was characterized by both drought‐ and grazing‐tolerant species. Two floristic archetypes located at the longitudinal extremes showed decreasing relative participation in the vegetation configurations, and the archetype located towards the west showed a positive relationship with annual precipitation, suggesting a threatened scenario in the face of drier conditions. Southern floristic archetypes either showed a slight decrease or remained stable. Conclusions: Patagonian steppes are dominated by both drought‐ and grazing‐tolerant species communities and their spatial distribution is expanding across different biomes, whereas the more forage‐preferred species were associated with a decreasing floristic archetype. A projected drier and hotter climate scenario may potentiate this pattern. The floristic archetypes framework has potential as a monitoring tool for tracking changes in vegetation composition at a mesoscale and for identifying hotspots of vulnerable vegetation in the face of environmental changes. [ABSTRACT FROM AUTHOR]

Aims: Restoration practitioners often face a tradeoff between low cost but risky seeding vs expensive but more reliable seedling planting to meet revegetation goals. Knowing under what environmental and management conditions direct seeding vs seedling planting benefit different species could improve restoration practice. Methods: We compared seed emergence to planted‐seedling survival among perennial herbaceous species commonly used in restoration across eight experimental restoration sites on the Colorado Plateau, USA. We used linear models to assess relationships between emergence and survival among species, and to assess the effects of site climate and seeding pre‐treatments on those relationships. Results: We found that among species, emergence was positively correlated with survival in the cooler sites, meaning that species with high emergence also had high survival and vice versa, but had no relationship in the hottest sites. Furthermore, pre‐treatments to enhance soil moisture in seeded plots, specifically microtopography (pits) and mulch, also resulted in positive relationships between emergence and survival among species, while seeding without additional soil pre‐treatments did not. Seedling planting cost 14 times as much as direct seeding alone, dropping to nine times as much when pre‐treatments were combined with seeding. Conclusions: Taken together, these results suggest that investments in seedling planting at hotter dryland sites, or in creating microtopography or mulching prior to seeding across sites, are likely to promote establishment success compared to simple seeding methods in degraded dryland ecosystems. These findings also identify opportunities for hybrid seeding and planting approaches that balance tradeoffs between risk and cost, respectively. [ABSTRACT FROM AUTHOR]

Question: Livestock grazing affects plant communities in drylands worldwide. However, our current understanding of the Patagonian drylands has primarily been derived from comparing exclosures with grazing conditions or from single‐site grazing gradients. The pending question is: do impacts of grazing intensification on Patagonian plant communities change along aridity gradients? Location: Patagonia, Argentina. Methods: We surveyed vegetation cover of perennial species in paddocks with different sheep‐grazing pressure (ungrazed, lightly, moderately, and intensively grazed, based on long‐term stocking rates), in three plant communities located along a regional aridity gradient: a semi‐desert (arid), a shrub–grass steppe (semi‐arid), and a grass steppe (dry sub‐humid). In these communities, we analyzed the effects of grazing pressure on the total cover of vegetation, the cover of dominant plant life‐forms (grasses and shrubs), the plant species diversity, and the traits of dominant plant species. Results: Intensification of sheep grazing significantly decreased total vegetation cover in the semi‐desert, but not in the steppes. Although grazing decreased the cover of grasses (particularly of the highly preferred ones) in all communities, in the shrub–grass and grass steppes this reduction was offset by an increase in the cover and size of shrubs. Plant diversity was not consistently affected by grazing pressure in these communities. Traits of dominant plant species partially explained community responses to grazing intensification. Conclusions: Livestock grazing intensification reduces the forage quantity and quality of Patagonian plant communities, but the severity depends on plant community types. In semi‐deserts (the most arid), grasses were drastically affected, while in the steppes, the grazing effects on grasses were low and partially compensated by an increase in the cover and size of shrubs, which fulfill critical roles other than forage provision. It is fundamental that grazing pressure be adapted to forage resource availability for each community type to achieve sustainable management in the context of climate change. [ABSTRACT FROM AUTHOR]

Aims: The influence of priority effects on plant community succession is increasingly discussed in community ecology. However, most grassland restoration approaches involving seed addition transfer all target species at the same time. Our objective was to tackle the question: does the order of arrival influence the establishment of restored communities? Location: La‐Bâtie‐Neuve, Southern Alps, France. Methods: We applied sequential sowing using two groups, one set of dominant species and one set of subordinate species, each comprising three different perennial plant species. We tested four sowing treatments: control (without any sowing), two sequential sowing treatments (dominants first or subordinates first) and synchronous sowing. We analysed plant cover each year for three years after sowing and calculated priority and earliness indices (the third year) for each group and each sown species. Results: Manipulating the order of arrival shaped community composition and trajectories. Some species of both groups were positively affected by being sown first compared to being sown synchronously. However, dominant and subordinate groups differed in their earliness index, showing a significant benefit for subordinates to be sown first. The subordinate species Onobrychis viciifolia and Plantago lanceolata established only when they were sown first, while Festuca cinerea showed greater establishment when sown first and simultaneously, compared to late sowing. The dominant Anthyllis vulneraria was not affected by date or type of sowing. However, the cover of the most dominant Bromopsis erecta was lower when being sown second, allowing a control of its dominance by delayed sowing. Conclusion: The strength of priority effects differs between species, which may depend on niche characteristics or microenvironment, influencing (negatively or positively) the establishment of late‐arriving species and affecting their competitive abilities. Our study provides evidence that plant community assembly was influenced by the order of arrival, but demonstrated a strong species‐specific response to priority effects. [ABSTRACT FROM AUTHOR]

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

Questions: Selective herbicides are frequently used in ecological restoration to control invasive non‐native forbs and recover plant communities. However, the long‐term efficacy of this practice, its non‐target effects on native plants, and its role in facilitating secondary invasions are not well understood. Similarly, little is known about the extent to which herbicide drift may affect native plant communities. Location: Foothills grasslands of Montana, USA. Methods: We conducted a 6‐year experiment to investigate changes in the abundance of a target invasive plant, knapweed (Centaurea stoebe subsp. micranthos) and plant community structure in response to the herbicides Tordon® (picloram) and Milestone® (aminopyralid), applied at a recommended rate and a diluted rate that simulated drift. Results: Knapweed cover and the richness of native and non‐native forb species declined in the first 3 years in response to treatment at recommended rates, but not drift rates. Secondary invasion by non‐native monocots was significant but weak. The cover of native forbs and the cover and richness of native monocots did not differ among treatments but changed significantly with the year. Surprisingly, 6 years after treatments, there were no differences among treatments in the cover of the target invasive plant or community structure. Conclusions: Our results demonstrate that the efficacy and non‐target effects of herbicides in grassland restoration can be short‐lived and idiosyncratic because of year effects. Restoration of knapweed invasions might require other active interventions, such as seeding or repeated spraying. Our study supports previous calls for long‐term monitoring of herbicides application in ecological restoration. [ABSTRACT FROM AUTHOR]

Questions: Our study focused on spontaneous vegetation in urban greenspaces in a Mediterranean city with the aim of relating plant community properties with ecological services along soil disturbance gradients. We asked which plant communities have the greatest plant biodiversity and soil carbon storage and the best‐performing nutrient cycles and water regulation. Location: Madrid City (Central Spain). Methods: We studied four types of plant communities following soil disturbance gradients: vegetation on trampled soils, roadside vegetation, annual grasslands and perennial forbs. Regarding vegetation, we studied plant composition and productivity, plant diversity, plant growth forms and functional groups. Regarding soils, we determined soil organic carbon (TOC), available nutrients, the activity of seven enzymes relating to the main macronutrient cycles, and physical properties such as bulk density (BD) and soil water‐holding capacity (WHC). We used one‐way ANOVA to determine the influence of the plant community type on both soil and vegetation variables. Canonical correspondence analysis was performed to interpret the relationships between plant species assemblages with environmental gradients. Results: Perennial forbs showed greater biomass and developed on soils with the greatest TOC and available phosphorus. Annual grasslands displayed the highest plant diversity. Roadside vegetation developed on soils with higher phenoloxidase activity when compared to vegetation on trampled soils and annual grasslands. Vegetation on trampled soils developed on soils with lower WHC, lower beta‐glucosidase, arylamidase and phosphatase activities and higher BD when compared to perennial forbs. Plant community distribution followed gradients most significantly associated with soil organic matter content, soil compaction and nutrient cycling performance. Conclusions: We conclude that plant communities are good indicators of ecosystem function and services which are unevenly distributed throughout urban habitats. The management in Mediterranean unmaintained urban greenspaces should be aimed at avoiding soil compaction to promote biodiversity, carbon storage and water regulation. [ABSTRACT FROM AUTHOR]

Questions: Rhododendron ponticum subsp. baeticum is an invasive shrub of growing concern in continental Europe, but little is known about its impact on native plant communities. Here we ask: do environmental conditions differ between forest stands invaded by it and uninvaded stands? Do these differences correlate with R. ponticum's cover? Are these differences associated with differences in taxonomic and functional diversity of vascular plant species of the herb layer? Can these vegetation changes be explained by the sorting of certain life‐history traits by R. ponticum‐induced environmental changes? Location: Several forests invaded by R. ponticum in the French Atlantic domain. Methods: We recorded vegetation composition and a number of environmental variables in 400‐m2 plots that were established in 64 paired forest stands (32 invaded vs 32 uninvaded). We compiled traits from existing databases. We computed several metrics of taxonomic and functional diversity. We compared environmental variables and diversity metrics between invaded and uninvaded stands. We used correlation and regression analyses to relate them with R. ponticum's cover. We ran RLQ and fourth‐corner analyses to explore the relationships between R. ponticum invasion, environmental variables, species traits, and vegetation composition. Results: Independent of its abundance, R. ponticum invasion was associated with lower light arrival at the forest floor and increased litter thickness. Concomitantly, species richness and diversity and trait diversity were reduced. The major driver of species assemblages was soil pH, which strongly interacted with the invasion gradient. R. ponticum did not sort species according to traits associated with shade tolerance and thick‐litter tolerance. However, tree and shrub saplings were more abundant in invaded than uninvaded stands, at the expense of graminoid and fern species. Conclusions: As R. ponticum becomes the dominant shrub, it exerts new selection forces on life‐history traits of extant species, mostly via reduced light availability, increased litter thickness, and physical competition, thereby reducing taxonomic and functional diversity of the herb layer, without impeding tree and shrub self‐regeneration, at least in the short term. [ABSTRACT FROM AUTHOR]

Aims: Responses of ecological restoration projects to disturbances are rarely explored, yet their capacity to withstand and recover from disturbance (resilience) is a critical measure of restoration success. In many plant communities, the soil seed bank (SSB) provides an important source of propagules for species persistence and community resilience to disturbance. Understanding how SSBs develop with time can inform restoration of resilient ecosystems. Here, in fire‐prone Banksia woodland restoration following sand mining, we ask: (a) how does the smoke‐responsive (dormancy broken by smoke) SSB develop over time; (b) what plant‐trait and climate factors influence its development; and (c) what do the data suggest for the resilience of these restored woodlands to fire? Location: Ellenbrook, Swan Coastal Plain, Western Australia (latitude −31.76, longitude 115.95). Methods: We used smoke, a key germination cue associated with fire disturbance, to trigger germination of the SSB in Banksia woodland restoration. Using a chronosequence of nine ages between 3 and 26 years since initiation of restoration, we tested how the SSB develops using counts and richness of germinating native and invasive annuals, and native perennial obligate seeding and resprouting species. To understand the contribution of above‐ground restored vegetation to SSB development, we compared Sørensen's similarity of the smoke germinable SSB (smoked SSB) and untreated germinable SSB (control SSB) with above‐ground vegetation. Results: Smoked SSB germinant density decreased with restoration age for both native and invasive annuals, but was stable for native perennials. Similarity between smoked SSB and above‐ground vegetation was higher for perennial obligate seeders than for resprouters and peaked for perennials at 23 years. Conclusions: Post‐fire regeneration potential of the SSB was evident across the chronosequence, with restoration age influencing the density of native annuals and overall composition of the SSB. The findings for perennial species suggest an increase in resilience to fire with restoration age.Seeds are necessary for successful restoration, but few studies track the development of the soil seed bank. Using smoke, we assessed germination of smoke‐responsive plant species across a restoration chronosequence. There was germination across the chronosequence, with composition changing with age. Our data for native perennial plant species suggest resilience of restored Banksia woodlands to fire increases with restoration age. [ABSTRACT FROM AUTHOR]

Questions: Management practices in permanent grasslands affect plant community structure and thus resources for both the herbivore and the decomposer subsystems. While their effects on digestibility or litter decomposition had been studied separately, few, if any, studies have tested the responses simultaneously and the underlying relationships with community functional structure. We tested whether the mass ratio hypothesis or the niche complementarity hypothesis held in scaling up from species to community level. Location: Dry calcareous rangelands of southern France on a limestone plateau. Methods: We measured digestibility and litter decomposability of 24 communities in three management regimes representing an intensification gradient corresponding to a combination of increased fertility and grazing. Key structural leaf traits (e.g. leaf dry-matter content, LDMC) and chemical traits (e.g. leaf nitrogen content, LNC, and leaf neutral detergent fiber, LNDF) were measured as well as communities' mean (i.e. community-weighted mean, CWM) and variance (i.e. community-weighted variance, CWV). Results: Digestibility and litter decomposability were higher in intensively grazed and fertilized than in lightly grazed and abandoned communities. Increased nutrient availability combined with more intense grazing induced an increase in CWM LNC and a decrease in CWM LDMC and CWM LNDF. Communities in these regimes were less functionally diverse, with lower CWV LDMC and lower CWV LNDF. Conclusions: The close relationship between digestibility and decomposability was maintained at the community level. Relationships between CWM, community digestibility and decomposability were more consistent across the management regimes than relationships with CWV, supporting the dominance rather than the complementarity hypothesis. [ABSTRACT FROM AUTHOR]

Aims: Channelization and artificial embankments have altered the natural flood regime of many rivers, impacting the hydrological characteristics of floodplain ecosystems and their biological communities. This study was undertaken on a floodplain meadow to assess spatial patterns of plant communities in relation to soil physical and chemical conditions, and the impacts of floodplain restoration that involved embankment-removal. Location: River Glaven, Hunworth, Norfolk, UK. Methods: Fine-scale plant and soil chemistry sampling was conducted prior to embankment removal, and hydrological and climatological conditions were monitored prior to and after embankment removal. Hydrological/hydraulic modelling simulated groundwater levels for a 10-year period to assess changes in soil aeration stresses and plant community composition following embankment-removal. Results: Hydrology was identified as the primary driver of plant community composition. Soil fertility was also important. Unique continuous measurements of vadose dissolved oxygen concentrations using oxygen optodes indicated strong coupling between water table depth and root zone dissolved oxygen concentrations. Reinstatement of overbank flows did not substantially affect aeration stress across most of the meadow because of pre-existing wet conditions. However, along the river-floodplain ecotone, aeration stress increased substantially from conditions normally associated with dry grassland to those characteristic of fen communities (p < 0.05). Conclusions: This restored water table regime may be suitable for more diverse plant assemblages. Benefits of flooding for increased species richness and transport of propagules may, however, be over-ridden without accompanying water level management during the growing season, or hay removal to balance additional supply of nutrients from river floodwater and sediment. Our results show that hydrological/hydraulic modelling combined with quantitative measures of plant water-requirements can provide practical and adaptive management tools to estimate the response of floodplain communities to changing water regimes. [ABSTRACT FROM AUTHOR]

Aims: Classification of plant communities and identification of their diagnostic species in different types of rocky outcrops in mountains from Central Argentina. We also explored how these plant communities differ in their endemisms, chorotypes and non-natives species composition, as well as in rock chemistry, elevation and climatic variables. Location: Córdoba Province, Central Argentina. Methods: The study was based on 505 phytosociological relevés collected from 2009 to 2019 using the Braun-Blanquet cover-abundance scale. The hierarchical ISOmetric feature mapping and Partition Around Medoids (ISOPAM) analysis was applied. The vegetation matrix was ordinated through isometric feature mapping (ISOMAP), and the geochemical and bioclimatic variables were related to the ISOMAP ordination. Results: We identified 14 plant communities distributed in three main clusters. We recorded 59 endemic species at the national level and 28 narrow endemics, restricted to the study area and nearby mountains. The number of non-native plants was relatively low (26 species). Perennial herbs (221 species), grasses (97 species) and shrubs (68 species) were the most prominent life forms. Plant communities were associated with rock chemistry (carbonate and acidic rocks), and also with elevation and climatic variables. Conclusion: This study highlights the remarkable heterogeneity of outcrop vegetation in Central Argentina. It reveals that elevation and rock type (geochemical composition) were relevant factors associated with the floristic composition of plant communities and also, that outcrop habitats comprise a high level of endemisms, as well as a low number of non-native species, suggesting a high value for the conservation of local and regional biodiversity. [ABSTRACT FROM AUTHOR]

Question: Alpine vegetation is sensitive to climate change, with shifts in species ranges, changes in community composition, and an upward shift in the forest limit over decades. Under climate change, habitats suitable for alpine vegetation will progressively decrease in scale, making their protection and conservation particularly important. In the Taisetsu Mountains of Japan, alpine vegetation has changed remarkably during the last decade. The aim of this study was to estimate the distribution of habitats suitable for alpine and subalpine vegetation types (snowbeds, shrubs, and alpine heathland/fellfield) and competing vegetation types (Sasa spp. and subarctic forest), while considering uncertainties in future predictions and climate scenarios. Location: Taisetsu Mountains, Daisetsuzan National Park, Hokkaido (northern Japan). Methods: We estimated the habitat area suitable for each vegetation type from current vegetation maps on the basis of the predictions by three global climate models (GCMs) under two climate change scenarios (RCP2.6 and RCP8.5) using five habitat suitability models (HSMs) in two periods (2046-2050 and 2096-2100). We also compared the performances of the HSMs. Results: Mean summer temperature and snow-cover period had significant effects on the distribution of all vegetation types. The estimated distribution area for suitable habitat did not differ markedly among GCMs and HSMs. Under the RCP2.6 scenario, habitats suitable for snowbeds and alpine heathland/fellfield drastically decreased overall but were preserved in some regions. Under the RCP8.5 scenario, however, subarctic forest almost completely replaced alpine and subalpine vegetation types over time. Conclusions: Our projections indicate that the severity of future climate change will determine whether or not habitats suitable for alpine vegetation will remain. Monitoring the dynamics of endemic and rare species for the effects of global warming should be the priority for adaptation strategies to enable timely conservation measures. [ABSTRACT FROM AUTHOR]

Question: Plant communities are structured by both equilibrium and non‐equilibrium dynamics, which interact at different spatiotemporal scales. The influence of external factors on internal regulation processes might depend on ecological state, and thus, on system resilience. We asked if well‐conserved (reference) states have higher resilience to external factors than degraded states, considering the greater capacity for self‐regulation expected of reference states. Location: Graminous–subshrubby steppes of northern Patagonia, Argentina. Methods: During four years, we assessed the influence of an external factor (rainfall variability) on internal regulation processes (seedling recruitment, growth of main perennial species, and three resilience proxies) in two alternative states (one reference and another degraded) of graminous–subshrubby steppes of northern Patagonia (Argentina). Specifically, we assessed the response of alternative states to simulated high rainfall events (irrigation). Results: The degraded state was more sensitive to rainfall variability than the reference state. Specifically, in the degraded state the density of surviving seedlings, the growth of shrubs and Papostipa speciosa's relative tiller production and cover increased in response to irrigation; whereas seedling emergence and survival, and grass growth were low or even null without irrigation. Finally, resistance and elasticity were lower whereas malleability was greater in degraded than in reference states. Conclusions: The degraded state was less resilient (low resistance and elasticity; high malleability) to stochastic weather events (in response to either increases or decreases in water availability. In contrast, the reference state had a great capacity to respond to rainfall variability. However, demographic processes such as seedling recruitment and vegetative growth were compensated by competition and mortality, suggesting a lower sensitivity to external drivers, and thus, a greater stability. By influencing the balance between equilibrium and non‐equilibrium dynamics, degradation might affect the resilience and stability of the ecosystem. Thus, to prevent rangeland degradation, management plans should anticipate climatically favorable and unfavorable periods. [ABSTRACT FROM AUTHOR]

Questions: Plant communities are shaped by interactions between natural and anthropogenic disturbances and underlying environmental conditions. We asked how disturbance by rock climbing alters patterns of cryptogam species diversity and composition along elevational abiotic gradients. Location: Red River Gorge, Kentucky, United States of America. Methods: Surveying was completed within 19 climbing routes on sandstone "slabs." Quadrats were placed at three different vertical positions (elevations) and three different horizontal positions (center of the route, route margin, off‐route). The former provides a gradient of light and moisture availability while the latter corresponds to climbing impact. Cryptogam species cover was visually assessed in all quadrats. Quadrat microtopography was quantified as well as route‐level Heat Load Index and Climbing Use Intensity. We assessed differences in species richness and Shannon diversity (H) among quadrat positions and evaluated differences in species and cryptogam morphological type abundance and composition. Results: Significant differences existed in richness H, and total cryptogam abundance between quadrat vertical and horizontal positions with a significant interaction between these two factors. Cryptogram abundance was greatest in off‐route quadrats and increased with elevation in such settings. Abundance was consistently lower in on‐route quadrats and, here, did not change with elevation. Richness and H were greatest in off‐route quadrats and declined with increasing elevation in on‐route quadrats. Significant differences in community composition existed as a function of vertical and horizontal position. On‐route quadrats were associated with crustose and granulose species, while foliose and squamulose lichens, and bryophytes were associated with off‐route quadrats. Conclusions: Cryptogam composition and abundance were associated with varying intra‐route environmental conditions, and off‐ to on‐route disturbance gradients. There is potential for substantive impacts on the ecology of cliff face ecosystems from climbing. Impacts could be reduced by spacing routes widely and avoiding impacts on upper elevations where diversity and abundance are greatest. [ABSTRACT FROM AUTHOR]

Aim: In this study, we tested plant community‐based management methods to reduce the abundance of the invasive native plant Jacobaea aquatica (marsh ragwort). As J. aquatica mainly occurs in species‐rich wet grasslands, our aim was to define management measures that do not reduce the conservation value of the resident communities. Location: Data were collected from 20 independent sites which varied in productivity and management intensity across the pre‐alpine Allgäu region (South Germany). Methods: We monitored effects of temporary abandonment and decreased mowing intensity in very low‐ and low‐productive sites, as well as of decreased mowing and fertilization at moderately productive sites. Abundances of J. aquatica and the co‐occurring species were recorded at start and end of two experiments (2018–2021: very low‐ and low‐productive conservation grasslands; 2017–2020: moderately productive agricultural grasslands), while functional traits data of all species were gathered from the literature and specific databases. Generalized linear mixed‐effects models (GLMMs) were used to analyse the effects of management intensity on the abundance of J. aquatica, functional diversity and species richness of the resident communities. Results: At all productivity levels, the abundance of J. aquatica declined under reduced management. Changes in community composition and species richness of the resident community were less pronounced than the reduction of J. aquatica, but species richness declined under lowest management intensities. Thus, moderate reduction in management intensity provided the most benefits in terms of reduction of J. aquatica, and maintenance of species richness and composition of the resident plant community. Conclusions: Reducing management intensity in wet grasslands decreases the abundance of J. aquatica and thus is a suitable method to control this species. As plant community responses were only partially consistent, management plans must account for the productivity of invaded sites. To avoid negative effects on grassland biodiversity, only moderate suppression of J. aquatica is recommended. [ABSTRACT FROM AUTHOR]

Question: Climate change scenarios predict alterations in interannual variability of precipitation and increases of extreme droughts. Drought effects will reflect ecosystems' sensitivity (i.e. the magnitude of the response relative to the change in amount of precipitation), with different consequences for plant communities and ecosystem functioning. However, sensitivity estimations across ecosystems and among years are contingent upon the metric applied. Here, we asked how different sensitivity indices reflect the responses to drought in contrasting ecosystems. Methods: We proposed a novel index to estimate sensitivity in drought experiments, which consider the change in the response variable in relation to the reduction in precipitation, standardized by the mean precipitation use efficiency of the site, making it suitable to compare among contrasting ecosystems. We compared the information gained from the new index with two indices commonly used in experimentally induced droughts, through simulated scenarios. Besides, we applied the indices to data from previous field drought experiments to evaluate relative and absolute sensitivity to drought in worldwide grassland ecosystems along a wide precipitation gradient. Results: We found that both relative and absolute approaches yielded important information to determine drought sensitivity in different simulated scenarios and under interannual precipitation variability. When the indices were applied to real situations, relative sensitivity to drought showed a significant increase as mean annual precipitation decreases whereas absolute sensitivity did not change significantly with precipitation. Conclusions: Our findings highlighted that absolute and relative indices to estimate drought sensitivity, rather than being redundant, may complement each other to inform how ecosystems respond to drought and to provide a more holistic assessment of vulnerable systems toward increasing interannual precipitation variability. This complementary approach enhances our understanding of ecosystem response under different conditions of precipitation variability and of the mechanisms that determine ecosystem changes during extreme droughts. [ABSTRACT FROM AUTHOR]

Aims: Ecological restoration is integral to meeting conservation goals in rapidly changing landscapes, but outcomes vary substantially with some projects failing to meet their targets. To understand the causes of this variability, long-term monitoring of existing projects is critical, but this comes at considerable costs. Current literature counts several studies using time series of satellite images to assess vegetation responses to disturbances and landscape transformations. Yet such methods are seldom used in the restoration literature and in practice. This synthesis seeks to identify how common remote sensing approaches for the assessment of plant recovery could inform the monitoring and management of restored plant communities. Methods: This paper reviews the methods and metrics used to detect trajectories (i.e., change through time) in plant properties from rich time series of aerial and satellite images following change drivers including fire, extreme climatic events, climate change, and pest outbreaks. Specifically, it reviews the sensors, vegetation properties, modeling approaches, and indicators that can help measure plant stress and response to interventions. Results and Conclusions: Remote sensing methods commonly used in disturbance ecology and assessments of land-cover changes could inform the monitoring of restoration projects at low cost and over large spatio-temporal scales, thus bridging the gap between field surveys to rapidly identify stressors or unexpected vegetation responses. Potential applications include comparing sites to identify factors impacting their responses to restoration, assessing restoration success, and testing ecological hypotheses to guide future project planning and design. [ABSTRACT FROM AUTHOR]

Questions: Selective herbicide application is a common restoration strategy to control exotic invaders that interfere with native plant recovery after wildfire. Whether spraying with pre-emergent or bio-herbicides releases native plants from competition with exotics (“spray-and-release” strategy) and makes communities resistant to reinvasion by exotic annual grasses (e.g. cheatgrass, medusahead), without risks to non-target native plants or secondary invasion, is a major question for land managers of semiarid plant communities. Location: Sagebrush steppe of southwest Idaho, USA. Methods: We applied chemical herbicides (imazapic, rimsulfuron) and weedsuppressive bacteria (Pseudomonas fluorescens strains MB906 and D7) to three sagebrush steppe communities after fire. We measured plant cover prior to burning and for four years (five for exotic annual grasses) post treatment. Results: Both chemical herbicides significantly reduced exotic annual grass cover in all communities in the first post-spraying year, but rimsulfuron plots were re-invaded after 1–2 years, while imazapic plots continued to resist reinvasion four and even five years post spraying, well after the herbicide should have degraded. We did not detect any increase in native perennial grass cover with either herbicide, and herbicides had both positive and negative effects on individual bunchgrass basal diameter, depending on species and plant community. Rimsulfuron was more damaging than imazapic to shallow-rooted perennial bunchgrasses. Moss and lichen cover, key components of soil integrity, increased with chemical herbicide treatments in some communities. Both herbicides increased secondary invaders (exotic forbs or grasses), which varied by plant community and herbicide. Weed-suppressive bacteria treatments had no significant effects on cover of any functional group. Conclusions: While short-term effects of chemical herbicides that target exotic annual grasses were relatively consistent and predictable, longer-term effects were specific to the herbicide and plant community. The “spray-and-release” strategy may confer resistance to re-invasion by exotic annual grasses if herbicides prevent re-invasion for an extended period. [ABSTRACT FROM AUTHOR]

Aim: We evaluated stands of the invasive grass, Sporobolus cryptandrus in its native North American range and its non-native European range, where it is a recent invader. Our aim was to reveal how the species’ increasing abundance affects functional diversity and the ecosystem service-provisioning capacities of plant communities in both ranges. Location: Sand grasslands in the Kiskunság, Hungary and in Montana, USA. Methods: All vascular plant species and their relative abundances were recorded in a stratified random manner in 1 m × 1 m plots in each range, using the following cover categories of Sporobolus as strata: 1%–25%, 26%–50%, 50%–75%, and 75%–100%. The functional characteristics of the plant communities in the two continents were compared. We performed comparisons of the communities both with and without including Sporobolus. Results: Increasing Sporobolus cover resulted in a lower functional diversity and species richness, reduced average specific leaf area and increased the height of whole plant communities in both ranges but these effects were significantly stronger in the non-native stands. Sporobolus also negatively affected the cover of insect-pollinated plant species and the proportion of native perennials, switching the rest of the community from perennial-dominated to annual-dominated. In plant communities without Sporobolus, increasing Sporobolus cover led to a higher specific leaf area and seed mass in both ranges, but average height was decreasing along the Sporobolus abundance gradient in the native range, whereas it was increasing in the non-native range. Conclusions: The spread of Sporobolus, away from its native range, leads to the impoverishment of host communities and compromises the biomass and floral resourceprovisioning capacity of the vegetation to higher trophic levels. Tackling the spread of this new invader should therefore be a priority task. [ABSTRACT FROM AUTHOR]

Question: Longleaf pine (Pinus palustris) restoration is an important management objective throughout the southeastern United States. Site preparation prior to planting longleaf pine seedlings is often required to overcome challenges to seedling establishment on hydric sites. We know site preparation improves growth and survival of planted longleaf pine on hydric sites, but what are the impacts of site preparation on the understorey plant community? Location: Marine Corps Base Camp Lejeune in Onslow County, NC, USA. Methods: This study tested eight site preparation treatments, including an untreated control, six combinations of two vegetation control treatments (chopping or herbicide) with three soil manipulation treatments (mounding, bedding, or flat‐planting [no treatment]), and a chopping–herbicide–bedding treatment. We collected data on understorey plant abundance, diversity, and composition through the first three and at 15 years after plantation establishment. We used ANOVA procedures and multivariate ordination to test for differences in understorey responses among the study treatments and through time. Results: Site preparation had lasting impacts on the understorey plant community. The chop‐only treatment was the only treatment that resulted in dominance of herbaceous vegetation and was among the treatments with the highest diversity and greatest abundance of Aristida stricta (wiregrass). Herbicide produced lasting reductions in Aristida stricta abundance and apparent shifts in community composition. Reduced graminoid abundance was particularly pronounced when herbicide was combined with soil manipulation treatments. Conclusions: Understorey responses to site preparation through 3 years differed from responses observed in year 15, highlighting the importance of long‐term monitoring. For example, herbicides controlled shrubs early, but by year 15, herbicide treatments were dominated by shrubs. Restoration scenarios often must balance ecological objectives (e.g., maintenance of a diverse understorey community) with forestry objectives (e.g., timely establishment of overstorey trees), and our findings can be used as a guide to balance these trade‐offs. [ABSTRACT FROM AUTHOR]

Aims: The Iberian oak wood‐pastures are unique agroforestry systems supporting high levels of biodiversity and ecosystem services. Small rocky outcrops are geological features commonly found in these systems and constitute biodiversity reservoirs, protecting sensitive species from grazing and farming activities. We aimed to assess the relevance of including rocky outcrop conservation within wood‐pastures to increase biodiversity. To achieve this goal, we studied the plant communities occurring within the outcrops and in the wood‐pasture matrix to evaluate the impact of rocky outcrops on the overall plant taxonomic and functional diversities of these systems. Location: Montemor‐o‐Novo (Alentejo, Portugal). Methods: We sampled 102 plant communities occurring in outcrops and the adjacent wood‐pasture matrix, and analysed alpha, beta, gamma and functional diversities. We identified the main intrinsic factors affecting outcrop plant composition and their functional groups using Linear and Generalized Linear Mixed models, and characterized the effect of outcrop size through Generalized Additive Models. Results: We found plant richness to be similar in wood‐pasture matrix and outcrops. However, β‐diversity analysis revealed a high species turnover between both communities. Functional indices indicated higher plant functional diversity in outcrops and trait analyses identified three functional groups dissimilarly distributed in both communities: (a) perturbation‐ and stress‐sensitive plants, with outcrops constituting an important refuge for this group; and (b) grazing‐tolerant and (c) weedy herbs dominating the wood‐pastures. Finally, we also found increased plant richness in outcrops with a longer length for their minor axis, i.e. wider outcrops, and greater rock cover area. Conclusions: Our results indicate that the presence of small rocky outcrops in evergreen oak wood‐pastures greatly increases their gamma and functional diversities. Consequently, outcrop protection strongly impacts overall wood‐pasture biodiversity and underlines the suitability of including outcrop conservation as a cost‐effective solution capable of increasing biodiversity in these agroforestry systems. [ABSTRACT FROM AUTHOR]

Some articles published in 2021 focused on traditional species-level analyses of vegetation change (e.g. Baumann et al., 2021), but others also conducted phylogenetic analyses of vegetation change, such as Santo-Silva et al. (2021), who found phylogenetic homogenization of tree assemblages in isolated forest patches in the Amazon. We also thank the authors for submitting articles to AVS, all the editors who managed the editorial process, and the referees (listed in Appendix 1) who helped improve the published articles. Applied Vegetation Science, 20, 161 - 163. https://doi.org/10.1111/avsc.12307 9 Kuhn, T., Domokos, P., Kiss, R. & Ruprecht, E. (2021) Grassland management and land use history shape species composition and diversity in Transylvanian semi-natural grasslands. [Extracted from the article]

Question: Which plant community characteristics most consistently vary with prior land use? Location: Oak Openings Preserve, Ohio, USA. Methods: In 2020, we measured plant communities on 22 sites encompassing three prior land uses: (a) contemporary Quercus forests continuously forested since before the 1930s; (b) former agricultural lands, under cultivation in the 1930s and abandoned 70–80 years before our study and that were unburned; and (c) former agricultural lands also abandoned 70–80 years earlier and that were burned in 2013 prescribed fires. Among the three land uses, we compared 12 plant community variables, categorized into four groups characterizing different sets of community properties (structure, diversity, composition, and conservation values). Results: A multivariate combination of the 12 community variables differed among all three land uses, each of the four categories of variables differed between at least two land uses, and eight of 12 individual variables differed between at least two land uses. Community structure displayed a gradient of decreasing tree canopy and understorey plant cover and increasing lichen–moss cover from continuously forested to unburned and burned formerly cultivated sites. Understorey plant species richness did not vary with land use, but species diversity was higher on cultivated sites, irrespective of fire history. While all three land uses now contain Quercus tree overstories, each land use exhibited unique understorey species composition. Only formerly cultivated sites contained state‐listed endangered species. Cultivated sites had a lower proportion of native species cover than did continuously forested sites, but native species still comprised over 90% of the plant cover on cultivated sites. Compared with continuous forests, the soil organic layer (O horizon) was five times thinner and loss on ignition in the 0–15 cm mineral soil 49% (unburned) and 66% (burned) lower on previously cultivated sites. Conclusions: Community characteristics varied in their sensitivity to land use history, with species composition among the most sensitive to prior land use. A dense sapling layer of Acer rubrum forming in long‐unburned Quercus forests across much of eastern North America was absent in our study on formerly cultivated sites, possibly due to dry, infertile soil. From a restoration and conservation standpoint of the study region's pre‐settlement, frequently burned and open savannas and woodlands, previously cultivated sites may be easier to keep open via prescribed fire. Moreover, perhaps precisely because much of the flora historically developed in open savannas and woodlands which previously cultivated sites on the contemporary landscape most closely mimicked, previously cultivated sites presently contain higher species diversity and more conservation priority species than do continuously forested sites. [ABSTRACT FROM AUTHOR]

Questions: Vegetation transects were surveyed in Saguaro National Park, Arizona, in 1976 and 2007 as part of a grazing study. We resurveyed the same transects in 2018 and accessed fire and climate data in order to examine trends in plant community structure. We asked the question: has the plant community shifted in species' density, canopy cover and diversity in the past 40 years since grazing cessation? And if so, do these shifts favor a specific species, or plant functional guild? We also asked if climate and time since fire influenced plant community structure? Location: Saguaro National Park East is located in the Sonoran Desert and Madrean Sky Island ecoregion interface in Tucson, Arizona, United States. Methods: Plots (10) were 20 m × 50 m, with 21 20‐m transects within each plot used to gather plant canopy cover and density of perennial species with the line‐intercept method. Data were aggregated by plot and analyzed using generalized linear mixed‐effects modeling and non‐metric multi‐dimensional scaling. Results: Overall canopy cover, density, and Shannon diversity increased significantly between 1976 and 2018. Ferns, forbs, graminoids, subshrubs and vines increased significantly in cover and density between 1976 and 2018. Wildfire recency was significantly negatively correlated with forb density, and density or cover of five dominant species (mostly woody). Shifts in plant community structure between survey years was correlated with increased temperature, precipitation, and vapor pressure differential. Conclusion: After 40 years of grazing cessation, significant increases in herbaceous cover, and a lack of significant increase in woody encroachment are signs of recovery. Increases in temperature may be responsible for accelerating shifts to warm‐season species‐dominant communities. Fire was unexpectedly not a significant factor in plant community structure; however, park management will likely need to address increased wildfire risk given the increase in herbaceous cover and density. [ABSTRACT FROM AUTHOR]

Aims: To conserve forest natural heritage, sustainable forest harvesting requires the recovery of plant diversity and ecosystem functions following management. There is a need to clarify the temporal dynamics of plant diversity following harvesting, for both even‐aged and uneven‐aged silvicultural systems. To achieve this goal, the temporal dynamics of plant diversity in the herb layer were measured in unmanaged forests (control) and along a chronosequence (<5 years, 15 years and 30 years after harvesting) for even‐aged and uneven‐aged managed forests. Location: Hardwood forest of southern Quebec, Canada. Methods: Plant diversity, plant community composition and ecosystem functioning were investigated using metrics exploring richness, evenness and disparity diversity components, and included two scales of diversity partitioning (alpha and beta). Shrub–canopy layer, forest tree species composition and structure, and total forest basal area were also measured. Results: In both uneven‐aged and even‐aged managed forest stands, we found: (a) a substantial decrease in mean plant phylogenetic diversity compared with unmanaged forest, even 30 years after harvesting (i.e., decrease of 16% and 22%, respectively); and (b) lowest plant alpha‐diversity in the herb layer 15 years after harvesting. Modification of community composition based upon dissimilarity (beta‐diversity) metrics demonstrated more numerous effects of even‐aged management than uneven‐aged management. For forest composition and structure, plant community and plant traits, dissimilarity relative to the unmanaged control was highest 5 years after even‐aged management. Trait‐based communities were more similar to unmanaged forest at the intermediate levels of forest density (i.e., ~20 m2/ha) that were found 5 years after uneven‐aged management. Conclusions: Forest management clearly affected diversity, community composition and ecosystem functions along the chronosequence, highlighting the strongest effects of more intensive management (i.e., even‐aged) and the need to improve the sustainability of forest management. [ABSTRACT FROM AUTHOR]

Questions: Grassland degradation due to agriculture, changing fire regimes, and invasive species negatively affects forb communities. Conserving forbs and the services they provide requires a better understanding of their responses to interacting disturbances. Although fire and livestock grazing are important disturbances, their effect on forb communities in the Pacific Northwest Bunchgrass Prairies is not fully understood. Our objectives were to: (a) determine how prescribed fire and livestock grazing influence forb community composition, cover, species richness, and diversity over a 10‐year span; (b) identify indicator species for each treatment; and (c) quantify forb responses to increasing cover of the invasive grass Ventenata dubia. Location: Pacific Northwest Bunchgrass Prairie, Oregon, USA. Methods: We monitored plant responses in a manipulative study established in 2004 with four treatments (prescribed fire, livestock grazing, both fire and grazing, and a control with no fire or grazing). Fall burns occurred in 2006 and 2016. Results: Forb communities changed significantly over 10 years and were influenced more by fire than cattle grazing. Treatments involving fire were more associated with annual forbs and fewer perennial species than treatments not burned. Although forb cover was lower in grazed compared to ungrazed treatments, richness and diversity did not differ among treatments. Several fire‐adapted forb species were associated with burned treatments. Forb cover and richness was negatively correlated with Ventenata dubia cover in 2016 and 2018 when cover of this invasive species reached 20%–37%. Conclusions: We found fall prescribed burns at a ten‐year return interval affected forb community composition and cover but not richness or diversity. Fire may promote annual and fire‐tolerant perennial forbs, but this relationship may be compromised by Ventenata dubia invasions. This study provides insights into management strategies aimed at conserving forb communities and emphasizes the need for continued monitoring of the Ventenata dubia invasion in this unique prairie. [ABSTRACT FROM AUTHOR]

Aim: We explore long‐term plant community responses 17 years after a one‐time application of biosolids (0, 50, 100, 150, 200, 250 dry Mg/ha) to determine: (a) whether the land application of biosolids on mine tailings, seeded with an agronomic grass‐legume mixture, affects long‐term plant community responses; (b) how application rates and soil texture influenced plant community responses and community structure; and (c) whether native plant species have colonized and contributed to the reclaimed plant community. Location: Two tailings deposits (sand and silt loam) generated by a copper–molybdenum (Cu–Mo) mine in southern British Columbia, Canada. Methods: Plant communities were sampled by visual evaluation of cover percentage to the lowest taxonomic level possible. Vegetation surveys were completed on two mine tailings deposits within the storage facility that have different soil textures (sand and silt loam). Results: Results showed that the interaction of biosolids applications and soil texture impacted multiple community plant responses, including increasing plant cover at both sites, and increasing richness, evenness and diversity at the sandy site. Biosolids application enhanced the performance of spontaneously established species (volunteer species) and non‐native/naturalized grasses. Conclusion: Our study demonstrated that biosolids application facilitates ecological succession by enhancing the establishment of non‐native volunteer species over the long term, which increases vegetative cover on both deposits and promotes plant communities' diversity on sites with sandy soil texture. [ABSTRACT FROM AUTHOR]

Question: Northern peatlands are increasingly threatened by wildfire. Severe peatland wildfires can provide opportunities for new non‐peatland species to colonise post fire. Changes in plant colonisation could lead to longer‐term shifts in community composition, compromising recovery of peatland structure and function. Understanding the process of post‐fire recovery can thus inform restoration action and help restore peatland vascular plant communities. In this study, we ask: what drives initial vascular plant recovery following a peatland wildfire? Location: Stalybridge moors, England (commonly referred to as the Saddleworth moors). Methods: We used a series of vegetation surveys and seed germination experiments to identify the composition of vascular plant community one‐year post fire, along with potential propagule sources. We combined this with plant trait data and, using a series of null models, compared observed community trait values against random species assemblages. Results: Our data suggests that plant species are able to arrive at the burned site through multiple non‐exclusive recolonisation pathways. This includes colonisation through the soil seed bank, along with dispersal from surrounding unburned peatland and non‐peatland vegetation. The composition and structure of the recolonised communities was largely determined by the ability of species to reach the post‐fire site from these donor communities. This resulted in a post‐fire community composed of species possessing lower seed masses relative to the wider pool of potential colonisers. Conclusions: Our results highlight propagule availability as a driver of post‐wildfire vascular plant recovery. This provides opportunities for new non‐peatland species to colonise, potentially driving changes in the direction of vegetation recovery. Ensuring the availability of peatland species following a wildfire could therefore be key to the immediate recovery of these systems. [ABSTRACT FROM AUTHOR]

Questions: Can multi‐decadal vegetation changes in a decommissioned brown coal mine be attributed to global‐change forcing? Given novel drivers of community assembly and ongoing global change, what are sensible restoration goals and strategies for large post‐industrial areas? Location: A decommissioned brown coal mine near Søby, central Denmark (56°01′45′′ N, 9°04′4′′ E). Methods: We resurveyed the plant communities of the mine 31 years after an initial survey. Changes in the prevalence of exotic species and species indicator values for environmental conditions were used to link the observed vegetation changes to global change factors. Results: The plant communities, including their unmined reference sites, changed over the 31‐year period toward plant communities with higher proportions of exotics, nitrophilous, warmth‐ and moisture‐indicating species, and species of low foraging quality for deer. The changes are consistent with the novel drivers of community assembly at the site, such as the introduction of exotic species, increased nitrogen deposition, elevated temperatures, steadily increasing groundwater level post mining, and the massive comeback of red deer. Conclusions: The global‐change forcing of novel plant communities suggests that it is becoming increasingly difficult to restore historical references. It may thus be more sensible to acknowledge novelty and adopt an open‐ended approach for the restoration of this and similar post‐industrial areas, e.g. using rewilding principles to promote biodiverse self‐sustaining ecosystems. [ABSTRACT FROM AUTHOR]

Questions: Agricultural intensification has led to the decline of biodiverse meadows and other semi‐natural grasslands. Road verges offer potential alternative habitats for meadow species, but they may not be suitable for all meadow species due to different soil properties, frequent disturbances, pollution or suboptimal management. Are their communities of vascular plants and bryophytes similar or dissimilar to those in mown or grazed meadows? What kind of species are associated with road verges, mown meadows or grazed meadows? How do the habitat types differ in their soil conditions and disturbance intensity? Location: The study was conducted at 36 sites in central Finland. Methods: We compared the vascular plant and bryophyte flora and the habitat characteristics of road verges, mown meadows and grazed meadows. Results: The community composition of both vascular plants and bryophytes differed among the habitat types. Many species occurred in all three habitat types, but several meadow specialists were absent or less frequent in the road verges. In contrast, road verges hosted more forest species and ruderal species, especially bryophytes. Road verges differed from meadows in their soil conditions. Conclusions: We conclude that although road verges may host some species typical to meadows, their value as alternative habitats could be increased by improved soil preparation and vegetation management. Meanwhile, the continued decline of quality habitats for meadow species underscores the need to maintain, increase and improve meadow management. [ABSTRACT FROM AUTHOR]

Questions: What are the main vegetation types of forest and shrubland vegetation at the alliance level in Mediterranean Turkey? What is their syntaxonomical position? Can we integrate them into the European vegetation classification system? Which environmental factors are the main drivers of the floristic differentiation of vegetation types? Location: Southern and western Turkey. Methods: We collected 4,717 vegetation plots of forest and shrubland vegetation in Mediterranean Turkey and performed an unsupervised classification of this data set. We described vegetation types based on the classification results, expert knowledge and information from the literature. We defined diagnostic species and prepared distribution maps for each vegetation type. To support the interpretation of the vegetation types, we determined the most important environmental variables using canonical correspondence analysis. Results: The studied vegetation was divided into 21 types related to three vegetation belts: (a) thermo‐ and meso‐mediterranean, comprising coniferous (Pinus brutia, Pinus pinea) and sclerophyllous forests, as well as macchia, garrigue and phrygana; (b) supra‐mediterranean, comprising Pinus nigra subsp. pallasiana forests, thermophilous deciduous forests dominated by various oak species and Ostrya carpinifolia, and forests dominated by temperate species such as Fagus orientalis; and (c) oro‐mediterranean, comprising forests and shrublands dominated by Abies cilicica, Cedrus libani, Juniperus excelsa and Juniperus communis subsp. nana. Elevation was identified as the main environmental driver of the vegetation pattern. Among climatic variables, the most important are the mean temperatures (annual and of driest, coldest, and warmest quarters), minimum temperature of winter, precipitation of warmest and driest quarters and precipitation seasonality. These factors indicate the decreasing effect of the Mediterranean climate with increasing elevation. Conclusions: The vegetation of Mediterranean Turkey is arranged along climatic gradients depending on elevation and the distance from the Mediterranean Sea. Most vegetation types in this area correspond to the syntaxa accepted in EuroVegChecklist, while others were described as new.Mediterranean Turkey comprises three vegetation belts: 1) thermo‐ and meso‐mediterranean, with coniferous (Pinus brutia, Pinus pinea) and sclerophyllous forests, as well as macchia, garrigue and phrygana (red dots), 2) supra‐mediterranean, with Pinus nigra, thermophilous oaks and Ostrya carpinifolia forests, and forests of temperate species (yellow dots), and 3) oro‐mediterranean, represented by Abies cilicica, Cedrus libani, Juniperus excelsa forests and Juniperus communis shrublands (blue dots). [ABSTRACT FROM AUTHOR]

Questions: Predicting the influence of climate change on riparian plant communities improves management strategies. The sensitivity of riparian vegetation to climate and other abiotic factors depends on interactions between properties of the ecosystem, like flood regime, and plant characteristics. To explore these interactions, we addressed three questions: (a) does the composition and diversity of riparian vegetation vary with the flood regime; (b) do abiotic correlates of vegetation, including climate and groundwater, differ between sites that flood compared to locations that did not experience floods; and (c) which plant functional groups account for differential plant community sensitivity to abiotic factors between flood regimes? Location: Middle Rio Grande Valley, New Mexico. Methods: We used long-term observations of plant community composition, groundwater depth, precipitation and interpolated temperature from 24 sites spanning 210 km of the Rio Grande riparian cottonwood-willow forest to explore the relative importance of climate and hydrologic correlates of riparian vegetation diversity and composition. Results: Riparian plant diversity was higher at sites flooding compared to non-flooding sites. Plant diversity positively tracked shallower groundwater depth at flooding sites, but was best predicted by intra-annual groundwater variability at non-flooding sites. Plant community composition correlated with groundwater depth and air temperature at all sites, but at non-flooding sites, also with intra-annual groundwater variability and precipitation. Relationships between native plant cover and potential environmental drivers diverged strongly between the two flood regimes; non-native plant cover had only weak relationships with most environmental predictors. Conclusions: The current flood regime of a site determined the climate and hydrologic factors that best predicted riparian plant community composition and diversity. Relationships between plant diversity or total cover and groundwater, temperature, precipitation, or groundwater variability can change in strength or direction depending on a site's flood history, highlighting the importance of flood regime to predicting the sensitivity of riparian woodlands to future environmental change. [ABSTRACT FROM AUTHOR]

Questions: Does plant composition differ among grasslands having divergent disturbance and management histories? Which vegetation attributes and disturbances specifically influence rangeland health? Location: Northern temperate pastures in the Central Parkland and adjacent Boreal natural regions of central Alberta, Canada. Methods: Plant composition and rangeland health data from 102 pastures were related to disturbance history acquired from retrospective producer surveys. Health assessments evaluated indicators such as vegetation composition, hydrologic function, and site stability. Producers were asked to identify pasture history (e.g., last cultivation date, whether fire had occurred), contemporary grazing actions (timing of use, grazing systems, type of livestock), and other management activities (i.e. herbicide application, manure spreading). Results: Cultivation and burn history were the primary drivers of vegetation differences, where previously cultivated pastures were dominated by introduced, naturalized grasses, eliminating most native species. Remnant non‐cultivated grasslands were occupied by a mix of native and invasive plant species. Grazing system had limited impact on vegetation composition due to uniformly high livestock stocking. Plant composition corresponded with gradients in rangeland health, where the latter declined with increased stocking rate and supplemental feeding on pasture. Greater health was characterized by increased cover of graminoids (primarily introduced forages), abundant litter, low plant richness, and reduced stocking rates. Other land management activities had comparatively less impact on the composition and health of these grasslands. Conclusions: Conversion of native grassland and forest in this region has a strong legacy effect on vegetation. Management actions associated with high stocking rates and supplemental feeding lowered rangeland health. [ABSTRACT FROM AUTHOR]

Questions: Is it possible to map floristic gradients in heterogeneous boreal vegetation by using remote‐sensing data? Does a continuous vegetation map enable the creation of a spatially continuous map of seasonal permafrost soil thaw depth? Location: Bonanza Creek LTER, Fairbanks, Alaska, USA. Methods: Vegetation records are subjected to an ordination to extract the predominant floristic gradient. The ordination scores are then extrapolated using Sentinel 2 imagery and a digital elevation model (DEM). As the relation between vegetation pattern and seasonal thaw depth was confirmed in this study, the spatial distribution of ordination scores is then used to predict seasonal thaw depth over the same area. Results: The first dimension of the ordination space separates species corresponding to moist and cold soil conditions from species associated with well‐drained soils. This floristic gradient was successfully mapped within the sampled plant communities. The extrapolated thaw depths follow the typical distribution along a topographical and geomorphological gradient for this region. Besides vegetation information also DEM derivatives show high contributions to the thaw depth modeling. Conclusion: We demonstrate that floristic gradient mapping in boreal vegetation is possible. The accuracy of the thaw depth prediction model is comparable to that in previous analyses but uses a more parsimonious set of predictors, underlining the efficacy of this approach. [ABSTRACT FROM AUTHOR]

Aims: Climate change will impact plant communities and populations but also individual plant performance. Most predictive models of community responses to climate change ignore individual‐level biotic interactions despite their known importance for community diversity and functioning. Here, we consider plant fitness and diversity responses to climate change associated factors at three organisational levels: communities, populations and individual plants, to increase our understanding of how plant communities respond to climate change. Location: Montane grassland, Tasmania, Australia. Methods: In two plant communities, we manipulated temperature using open‐top chambers and removed random and dominant species biomass. Two years after experimental manipulations, we assessed the impact of treatments on species diversity, community‐ and population‐level functional traits and individual plant fitness. Results: Species diversity was affected by warming in one of the two communities, while community‐level functional trait diversity metrics were unaffected by treatments. Mean community trait values were strongly impacted by dominant species biomass removal in both communities, notably increasing specific leaf area (SLA) and specific root length. SLA showed the strongest population‐level trait response, with higher values found in warmed plots and lower values found in dominant species biomass removal plots. Neighbours had a stronger competitive effect on individual plant fitness in warmed compared to unwarmed conditions at the higher‐elevation site and facilitation was common in both communities. Conclusions: We demonstrated that over short time scales, plant communities respond to experimental warming and biomass removal across multiple organisational levels. Competitive and facilitative interactions played a significant role in determining fitness outcomes, but competitive interactions dominated under warmed conditions. We highlight the importance of local‐scale biotic interactions in mediating individual responses to warming and recommend their inclusion in future studies of how climate change will impact the long‐term structure and function of plant communities through short‐term impacts on individual plant fitness. [ABSTRACT FROM AUTHOR]

Questions: Biosolids are a source of nutrient‐rich organic material that can be used to improve degraded or disturbed soils. Research on vegetation responses to the land application of biosolids has increased in the past 20 years, but there is no consensus on how plant communities respond to biosolids applications. What factors influence productivity and vegetative cover following biosolids application for grassland reclamation? How does the addition of biosolids impact plant community responses? Location: Global, but predominantly North America and Europe. Methods: To explore vegetative responses following biosolids application, we used a global systematic review and meta‐analysis of 59 articles. Our meta‐analysis used the log response ratio (LRR) as an effect size for productivity, total cover, species richness, diversity and exotic species abundance and explored covariates addressing various site characteristics and reclamation strategies. Results: We found that across sites, the land application of biosolids significantly increased productivity and cover but had no significant overall effect on species richness, Shannon diversity or exotic species abundance on degraded lands. These increases in the LRR for productivity and vegetative cover were lower on sites that experienced a fire prior to biosolids application. Climatic variables like mean annual temperature were shown to alter the response of vegetative cover, where warmer sites tended to have more positive responses to biosolids. Seeding was found to increase plant cover but decrease species richness early in the reclamation process. Conclusions: This area of research is growing; most of the publications we used come from the last 20 years and were mostly conducted in North America and Europe. While we can build on the present literature, there is clearly room for more research to ensure the process of reclaiming degraded ecosystems using biosolids results in desired plant communities, e.g. high native species diversity. Future research should consistently report biosolids chemical characteristics as well as application and processing methodologies. [ABSTRACT FROM AUTHOR]

Questions: Does urbanization promote biotic differentiation or homogenization of swamp plant communities? What is the contribution of natives and exotics to swamp response to urbanization? Location: Quebec City, Canada. Methods: Plant communities of 34 swamps located in low, moderately or highly urbanized landscapes were sampled, and species classified into three exclusive groups: native wetland, native upland and exotic plants. Urbanization's influence on the richness of each plant group was assessed using mixed models. Between‐site compositional similarities were calculated to identify variations in beta diversity with urbanization level using tests for homogeneity in multivariate dispersion. Beta diversity was further partitioned into species replacement and richness difference for each plant group. Finally, the relationships of ten environmental variables representing soil water saturation and microtopography with plant assemblages were determined by redundancy analysis. Results: Although the richness of exotics increased with urbanization intensity, revealing increasing propagule pressure, it remained six to 27 times lower compared to the richness of natives, which remained stable with urbanization. On the other hand, beta diversity increased with urbanization, with higher dissimilarities in species composition between highly urbanized swamps than between low‐urbanized ones. This pattern resulted from high species replacement among natives, while richness difference mainly contributed to exotic beta diversity. Changes in plant assemblages were mostly associated with bryophyte cover and soil drainage and red mottle size, suggesting that hydrological conditions likely acted as a strong driver of swamp plant community response to urbanization. Conclusions: Swamp plant communities experienced biotic differentiation with increasing urbanization. This differentiation pattern likely was linked to the unpredictable effect of urbanization on hydrological regimes, which promoted high native turnover while limiting exotic spread. Long‐term monitoring is recommended to ensure that exotics do not outcompete natives through time. Designing sustainable cities requires a greater understanding of the multifaceted effect of urbanization on biodiversity. [ABSTRACT FROM AUTHOR]

Questions: The soil seed bank is an important ecosystem component that can be pivotal for long‐term persistence of many plant species, especially after disturbances followed by the invasion of alien weeds. However, many Great Basin Desert perennials produce relatively few viable seeds, while large areas of the Great Basin are currently invaded by alien weeds. This could result in dissimilarity in floristic composition between the above‐ground vegetative community and the soil seed bank, causing abrupt plant community shifts following disturbance. Therefore, we asked what is the relationship in the floristic composition between the above‐ground communities and the soil seed bank in sites where the threatened Ivesia webberi occurs? Location: The Great Basin Desert, United States. Methods: We used Dice–Sorensen's similarity index to estimate similarity between the standing vegetation and the soil seed bank. Redundancy analysis and variation partitioning were used to quantify the relationship between the total abundance of the sampled above‐ground flora and the soil seed bank, accounting for effects of spatial processes and environmental variables describing climate, soils, and vegetation in the 10 sites. Results: Findings reveal high dissimilarity in species assemblage and abundance between the above‐ground plant communities and the soil seed bank. Most of the dominant native plant species sampled in the standing vegetation were absent in the soil seed bank, and the soil seed bank was dominated by invasive alien weeds. Conclusions: Divergence in the floristic composition between the above‐ground communities and the soil seed bank in Ivesia webberi habitat indicates low resilience and high risk of native species loss following perturbation. Post‐disturbance succession in these plant communities may be largely dominated by invasive annual species; therefore, reduction of invasive species and native plant seeding may be necessary to sustain the ecological legacies of the desert ecosystem. [ABSTRACT FROM AUTHOR]

Question: Reed beds, dominated by common reed (Phragmites australis), have high ecological value. Several studies have examined the differences between managed and unmanaged reed beds without taking into account the time passed since the last management. In this paper, we seek to answer the question: how does the time passed since last management and the management method itself affect the plant community and the habitat structure of reed beds? Location: "De Østlige Vejler," Northern Jutland, Denmark. Methods: We examined four reed bed treatments — beds either cut or harvested during the year of the study (0‐year‐old reed beds) and reed beds harvested 3 and 25 years ago, respectively. The reed bed plant communities and the reed bed habitat structure were determined in May and August. We tested the data for overall between‐treatment differences (multivariate analysis of variance [MANOVA] and principal components analysis [PCA]) and specific differences in the plant community and habitat structure (Kruskal–Wallis). Results: The plant community differed significantly between the four reed beds according to treatment, and each reed bed exhibited unique species. Species richness was significantly higher in the recently harvested reed beds (0 and 3 years since harvest) compared with the 25‐year‐old reed beds. Harvest sparked reed rejuvenation and increased the growth of new reeds. The 3‐year‐old reed bed had a habitat structure that equally resembled that of the newly harvested (e.g., similar green reed shoot density) and the 25‐year‐old reed beds (e.g., similar height). Cutting, as opposed to harvesting, created a plant community adapted to less light availability. Conclusions: To secure most plant species and most variation in habitat structure, reed beds should contain a mosaic of differently aged and differently managed patches. Previous studies have disagreed on the effect of management on plant species diversity, which could be explained either by different reed bed age or different sampling periods. [ABSTRACT FROM AUTHOR]

Question: Species of the genus Carpobrotus, or ice plant, are succulent mat‐forming perennial herbs often introduced for soil stabilization. They are common in coastal environments and may thus threaten island biodiversity. While their effects are well known on soils, plant communities and associated fauna, the effects of Carpobrotus control on vegetation recovery are poorly documented. The aim of the paper is to describe plant community trajectories after Carpobrotus removal. Location: Bagaud: a 58‐ha Mediterranean island, southern France. Methods: Carpobrotus and its litter were removed in 2011–2012. Follow‐up controls of germinations and resprouts were carried out from then on. Plant communities were surveyed every year two years before and seven years after Carpobrotus removal: on two ca. 0.5‐ha sites (one coastal and one inland) and in three native plant communities used as potential references. Differences in resprouts, vegetation parameters, and Bray–Curtis similarity indices between years were tested. Plant community dynamics was studied through a non‐metric multidimensional scaling and two recovery indices. Results: The removal of Carpobrotus and its litter led to the recovery of diverse native plant communities. To prevent Carpobrotus return and ensure success, follow‐up controls were necessary for a period of at least seven years, but the amount of work decreased with time. The plant community recovering on the coastal site quickly reached a composition and structure similar to that of non‐invaded coastal vegetation, although some slow‐growing native species remain underrepresented (e.g., Crithmum maritimum and Limonium pseudominutum). The plant community recovering on the inland site was still very different from the surrounding matorral vegetation because of its slow colonization dynamics, particularly in the presence of competitive herbaceous species. Conclusion: Both sites now provide diverse native plant communities with a more diversified composition and structure (plant heights, litter, bare ground patches) than the plant communities which used to be associated with Carpobrotus mats. [ABSTRACT FROM AUTHOR]

Aims: Assigning vegetation plots to vegetation units is a key step in biodiversity management projects. Nevertheless, the process of plot assignment to types is usually non‐standardized, and assignment consistency remains poorly explored. To date, the efficiency of automatic classification programs has been assessed by comparing them with a unique expert judgment. Therefore, we investigated the consistency of five phytosociology expert judgments, and the consistency of these judgements with those of automatic classification programs. Location: Mainland France. Methods: We used 273 vegetation plots distributed across France and covering the diversity of the temperate and mountainous forest ecosystems of Western Europe. We asked a representative panel of five French organizations with recognized expertise in phytosociology to assign each plot to vegetation units. We provided a phytosociological classification including 228 associations, 43 alliances and eight classes. The assignments were compared among experts using an agreement ratio. We then compared the assignments suggested by three automatic classification programs with the expert judgments. Results: We observed small differences among the agreement ratios of the expert organizations; a given expert organization agreed with another one on association assignment one time in four on average, and one time in two on alliance assignment. The agreement ratios of the automatic classification programs were globally lower, but close to expert judgments. Conclusions: The results support the current trend toward unifying the existing classifications and specifying the assignment rules by creating guiding tools, which will decrease inter‐observer variation. As compared to a pool of phytosociology experts, programs perform similarly to individual experts in vegetation unit assignment, especially at the alliance level. Although programs still need to be improved, these results pave the way for the creation of habitat time series crucial for the monitoring and conservation of biodiversity. [ABSTRACT FROM AUTHOR]

Questions: A recently introduced non‐native annual grass, Ventenata dubia, is challenging previous conceptions of community resistance in forest mosaic communities in the Inland Northwest. However, little is known of the drivers and potential ecological impacts of this rapidly expanding species. Here we (1) identify abiotic and biotic habitat characteristics associated with the V. dubia invasion and examine how these differ between V. dubia and other problematic non‐native annual grasses, Bromus tectorum and Taeniatherum caput‐medusae; and (2) determine how burning influences relationships between V. dubia and plant community composition and structure to address potential impacts on Inland Northwest forest mosaic communities. Location: Blue Mountains of the Inland Northwest, USA. Methods: We measured environmental and plant community characteristics in 110 recently burned and nearby unburned plots. Plots were stratified to capture a range of V. dubia cover, elevations, biophysical classes, and fire severities. We investigated relationships between V. dubia, wildfire, environmental, and plant community characteristics using non‐metric multidimensional scaling and linear regressions. Results: Ventenata dubia was most abundant in sparsely vegetated, basalt‐derived rocky scablands interspersed throughout the forested landscape. Plant communities most heavily invaded by V. dubia were largely uninvaded by other non‐native annual grasses. Ventenata dubia was abundant in both unburned and burned areas, but negative relationships between V. dubia cover and community diversity were stronger in burned plots, where keystone sagebrush species were largely absent after fire. Conclusions: Ventenata dubia is expanding the overall invasion footprint into previously uninvaded communities. Burning may exacerbate negative relationships between V. dubia and species richness, evenness, and functional diversity, including in communities that historically rarely burned. Understanding the drivers and impacts of the V. dubia invasion and recognizing how these differ from other annual grass invasions may provide insight into mechanisms of community invasibility, grass‐fire feedbacks, and aid the development of species‐specific management plans. [ABSTRACT FROM AUTHOR]

Questions: The Mediterranean mountain massifs are biodiversity hotspots threatened by climate change and land use transformations, among other factors. Did vegetation composition and α‐ and β‐diversities change in mid‐ and high‐elevation Mediterranean ecosystems over the last 46 years? Can these changes be explained by climate change or land use? Location: Medium and high altitudes of the Penyagolosa Massif, Castellón, Eastern Spain. Methods: In 2014, we resurveyed 92 vegetation plots sampled in 1968, belonging to nine plant communities distributed on basic and acid soils. We performed estimates of α‐ and β‐diversity, multidimensional ordination of species composition, ecological characterisation of species and non‐parametric tests to identify vegetation change over time. Results: We observed different patterns of vegetation change depending on the plant community; an increase in α‐diversity, especially in high‐altitude habitats, and a homogenisation of species composition among plant communities. Seral communities and forests increased particularly in locations on basic soils that used to be occupied by pastures and communities of degraded successional stages. Higher Ellenberg indicator values of temperature and light, and loss of temperate taxa, which are usually rare in the region, were found in the climax forest of high altitudes and some acidophilous communities. However, altitudinal shifts of species distributions were detected only in 14% of plant species, both upwards and downwards. An increase of nitrophily at medium altitudes was also observed. Conclusions: The results suggested that land use change related with abandonment of agro‐sylvo‐pastoral systems was the major driving force of vegetation dynamics in most of the seral plant communities, while thermophilisation was more evident in the high‐altitude climax forest. [ABSTRACT FROM AUTHOR]

Questions: How does small‐scale soil disturbance influence establishment dynamics of native and exotic species along roadsides? Does soil disturbance provide potential opportunities to exotic invasions along elevational gradients? Does the established plant community after disturbance reflect the surrounding vegetation? Location: Prealps, Italy. Methods: To disentangle the role of elevation and soil disturbance in promoting exotic invasions, we performed a manipulative experiment along 12 roads spanning an elevational gradient of ca. 1,200 m. Additionally, we sampled species richness of native and exotic plants in the surroundings of the experimental plots. Results: Soil disturbance reduced species richness of native plants, total plant biomass and vegetation cover compared to the undisturbed plots. The decrease in species richness of natives and plant biomass was stronger at higher than lower elevations, suggesting higher colonization opportunities for exotics. However, exotic species richness did not increase with disturbance, probably due to a low propagule and colonization pressure. We observed strong species replacement between control and disturbed plots, indicating that plant communities established after disturbance were not a subset of species communities already occurring in the surrounding vegetation. Conclusions: With increasing elevation, disturbance had a stronger negative effect on native than on exotic species. Higher elevations, hitherto considered to have low invasibility, may provide new potential colonization opportunities for exotics but only if disturbance is coupled with an increased propagule pressure. Disturbance along roadsides promoted the establishment of species that did not occur in the surrounding vegetation. [ABSTRACT FROM AUTHOR]