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Trophic rewilding is gaining rapid momentum as a means of restoration across the world. Advances in research are elucidating the wide‐ranging effects of trophic rewilding and megafauna re‐establishment on ecosystem properties and processes including resilience, nutrient cycling, carbon sequestration, productivity and plant richness.A substantial gap remains in trophic rewilding research on how rewilding affects the frequency and expression of plant functional traits, a key hypothesised avenue by which megafauna can affect biodiversity and ecosystem processes. Yet, there is extensive literature examining the effects of mammal herbivory and exclusion on plant traits from which we may infer potential effects of megafauna reintroductions.Here, we synthesise the literature to show the multifaceted ways that plant functional composition responds to mammalian herbivory and explore how these responses are modulated by the density and identity of herbivores as well as resource availability, ecosystem productivity and historical contingency. We further explore these interactions in a quantitative analysis on European plant species. In addition, we link these broad patterns between mammal herbivory and traits to literature on plant invasions to predict how trophic rewilding may be able to reduce invasive plant dominance, as ecosystems around the world are transitioning towards novel states, occupied by a mix of native and introduced species.Expanding current research on herbivore effects (and their implications for trophic rewilding) beyond plant species richness and towards measurable functional traits can help assess and quantify processes that were not previously possible. Trait approaches can help to test mechanistic hypotheses on the top‐down impacts of large herbivores on plant communities to reveal links between trophic rewilding and ecosystem processes and properties.Synthesis. Given the rapid, much‐needed expansion of restoration and rewilding activities across the world, trait‐based ecology offers a pathway to generalisable predictions of the ecosystem impacts of rewilding, particularly in the context of both the unique landscape processes associated with rewilding (e.g. landscape scale spatiotemporal variability, dispersal) and of widely emerging novel ecosystems. [ABSTRACT FROM AUTHOR]

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Questions: Does the non‐native evergreen Chinese windmill palm (Trachycarpus fortunei) affect native plant community and forest regeneration in deciduous forests? Are effects modulated by soil moisture? What are the implications for forest management and nature conservation? Location: Broadleaved deciduous low‐elevation forests on the southern slope of the Alps across the Swiss–Italian border region. Methods: We compared the native herbaceous and woody plant composition, species richness, Shannon diversity and abundance at ten deciduous forest sites on two moisture conditions (six mesic–moist sites and four mesic–dry sites). Each site consisted of three plots measuring 400 m2 along a gradient of T. fortunei presence, ranging from "dominant", to "present but not dominant" to "absent". Results: In mesic–moist forests with high densities of T. fortunei, species richness and Shannon diversity of native plants and recruiting woody species in the herb and shrub layers were significantly reduced compared to similar sites where T. fortunei is absent or not dominant. However, in mesic–dry forests these variables did not differ between palm‐invaded and uninvaded plots. The abundance of recruiting woody individuals did not differ between plots invaded by palms and uninvaded control plots in either forest type. Conclusions: We expect detrimental consequences for plant diversity in mesic–moist alluvial forests with high T. fortunei densities and few detrimental consequences in the more widespread non‐alluvial forests. We recommend multifaceted management, including targeted eradication in alluvial forests identified as hotspots of native plant diversity, accompanied by hands‐off management of T. fortunei in non‐alluvial forests, recognizing the ongoing and inevitable "laurophyllisation"; a biome shift toward mixed‐evergreen forest that may increase ecosystem climate resilience under ongoing climatic warming. [ABSTRACT FROM AUTHOR]

African wildlife populations are declining at an alarming rate. To stop further population declines and restore ecosystems, more areas for wildlife are needed. Community‐based conservation with wildlife‐livestock coexistence in the vast rangelands of Africa presents a major opportunity. However, the efficacy of wildlife conservation in mixed land‐use areas remains an outstanding question. To assess the ecological outcomes of land‐sharing between regulated livestock herds and wildlife populations in African savannas, we test how rotational cattle grazing affects spatiotemporal dynamics of 15 large herbivore species in the Maasai Mara, Kenya.First, we tested how wild herbivore distributions across the Greater Mara Ecosystem (the Mara, ~2600 km2) are related to cattle density and environmental variables using 584,561 observations of wild herbivores (ecosystem scale). In a second analysis, we tested how rotational cattle grazing affects wild herbivore distributions in a 300 km2 subsection of the Mara using 30,583 observations (landscape scale). Finally, we tested how functional traits of wild herbivores affect species‐level spatiotemporal responses to cattle grazing.At the ecosystem scale, the presence of five wild herbivore species was positively correlated with cattle density, while cattle effects on wild herbivore abundances were species‐dependent with both increases and decreases. At the landscape scale, rotational cattle grazing strongly impacted the spatiotemporal habitat selection of wild herbivores, resulting in distinct lag periods with which different species are attracted to areas previously grazed by cattle. These lag periods were linked to functional traits, with body mass and herd size explaining 35% of the interspecific differences. Small to medium‐sized herbivores with large herds select areas recently grazed by cattle, whereas large species with large herd sizes and small species with small herd sizes avoid recently grazed areas.Synthesis and applications: Our results revealed that the effect of cattle on wild herbivores varies considerably among species, suggesting that cattle‐wildlife interactions range from facilitation to competition. To maintain species that strongly avoid cattle, designated livestock‐free zones remain essential, also in rotational grazing systems. Rotational grazing systems with regulated livestock densities present an important opportunity to better manage wildlife‐livestock coexistence and thus improve wildlife conservation in African rangelands. [ABSTRACT FROM AUTHOR]

Ecological processes and biodiversity patterns are strongly affected by how animals move through the landscape. However, it remains challenging to predict animal movement and space use. Here we present our new r package enerscape to quantify and predict animal movement in real landscapes based on energy expenditure.enerscape integrates a general locomotory model for terrestrial animals with GIS tools in order to map energy costs of movement in a given environment, resulting in energy landscapes that reflect how energy expenditures may shape habitat use. enerscape only requires topographic data (elevation) and the body mass of the studied animal. To illustrate the potential of enerscape, we analyse the energy landscape for the Marsican bear (Ursus arctos marsicanus) in a protected area in central Italy in order to identify least‐cost paths and high‐connectivity areas with low energy costs of travel.enerscape allowed us to identify travel routes for the bear that minimize energy costs of movement and regions that have high landscape connectivity based on movement efficiency, highlighting potential corridors. It also identifies areas where high energy costs may prevent movement and dispersal, potentially exacerbating human–wildlife conflicts in the park. A major strength of enerscape is that it requires only widely available topographic and body size data. As such, enerscape permits a first cost‐effective way to estimate landscape use and movement corridors even when telemetry data are not readily available, such as for the example with the bear.enerscape is built in a modular way and other movement modes and ecosystem types can be implemented when appropriate locomotory models are available. In summary, enerscape is a new general tool that quantifies, using minimal and widely available data, the energy costs of moving through a landscape. This can clarify how and why animals move in real landscapes and inform practical conservation and restoration decisions. [ABSTRACT FROM AUTHOR]

Aims: Novel ecosystems are self‐maintaining ecosystems that support species assemblages without historical precedent. Despite much interest and controversy around novel ecosystems, it remains poorly understood how they are generated, what their capacity to support biodiversity is and what the implications for society are. Here, we address these issues through a global synthesis of non‐native palms, since palms are likely generators of novel ecosystems because they are introduced widely beyond their native range and have the capacity to act as ecosystem engineers. Location: Global. Methods: We gathered data on non‐native palms from peer‐reviewed literature/papers, grey literature and online databases. We extracted data on the biogeographic context of palm invasions, plant functional traits and anthropogenic drivers to quantify their effects on biodiversity, ecosystem functioning and ecosystem services. Results: Of the 2,557 palm species, 3.4% (86 species) were recorded as naturalized and 1.1% (28 species) as invasive, which exceeds the average invasion success across all woody plants. Naturalized palms are present in most tropical and subtropical regions around the world, often in urban areas, reflecting the use of palms in horticulture. Many naturalized palms were taller and more likely to originate from open habitats or dry forest than non‐naturalized palms. These features likely represent the naturalized palms' competitive ability, high fecundity and dispersal ability along with ecological matching to human‐disturbed environments. Overall, literature on ecological effects of palm invasions was sparse, but we found multiple cases in which palm invasions resulted in strong ecosystem changes or even biome shifts. Main Conclusions: We found strong evidence that palm invasions can generate novel ecosystems. Although there are substantial knowledge gaps on the ecological effects of palm invasion, anthropogenic drivers like urbanization and ongoing global warming will continue to expand palm ranges and promote non‐native palms as generators of novel ecosystems. [ABSTRACT FROM AUTHOR]

Aim: Theory suggests that increasing productivity and climate stability towards the tropics favours specialization, thus contributing to the latitudinal richness gradient. A positive relationship between species richness and specialization should therefore emerge as a fundamental biogeographical pattern. However, land‐use and climate changes disproportionally increase the local extirpation risk for specialists, potentially weakening the relationship between richness and specialization. Here, we quantify empirically the richness–specialization prediction and test how 50 years of climate and land‐use change has affected the richness–specialization relationship. Location: USA. Time period: 1966–2015. Major taxa studied: Birds. Methods: We used the North American Breeding Bird Survey to quantify bird community richness and specialization to habitat and climate. We (a) quantify temporal change in the slope of the richness–specialization relationship, using a generalized mixed model; (b) assess how this change translates spatially, using generalized additive models; and (c) attribute spatio‐temporal change in the richness–specialization relationship to land use, climate and topographic drivers. Results: We found evidence for a positive but weak richness–specialization relationship in bird communities that greatly weakened over time. Given that specialization was not the main driver of richness, this relationship did not translate spatially into a linear spatial covariation between richness and specialization. Instead, the spatial covariation in richness and specialization followed a unimodal pattern, the peak of which shifted towards less specialized communities over time. These temporal changes were associated with precipitation change, decreasing temperature stability and land use. Main conclusions: Recent climate and land‐use changes have induced two contrasting types of community responses. In human‐dominated areas, the decoupling of richness and specialization drove a general trend for biotic homogenization. In areas of low human impact experiencing increasing climate harshness, specialization increased, whereas richness decreased. Our results offer new support for specialization as a key driver of macroecological diversity patterns and show that global changes are weakening this fundamental macroecological pattern. [ABSTRACT FROM AUTHOR]

The satellite record has revealed substantial land surface "greening" in the northern hemisphere over recent decades. Process‐based Earth system models (ESMs) attribute enhanced vegetation productivity (greening) to CO2 fertilisation. However, the models poorly reproduce observed spatial patterns of greening, suggesting that they ignore crucial processes. Here, we explore whether fine‐scale land cover dynamics, as modified by ecological and land‐use processes, can explain the discrepancy between models and satellite‐based estimates of greening. We used 500 m satellite‐derived Leaf Area Index (LAI) to quantify greening. We focus on semi‐natural vegetation in Europe, and distinguish between conservation areas and unprotected land. Within these ecological and land‐use categories, we then explored the relationships between vegetation change and major climatic gradients. Despite the relatively short time‐series (15 years), we found a strong overall increase in LAI (i.e., greening) across all European semi‐natural vegetation types. The spatial pattern of vegetation change identifies land‐use change, particularly land abandonment, as a major initiator of vegetation change both in‐ and outside of protected areas. The strongest LAI increases were observed in mild climates, consistent with more vigorous woody regrowth after cessation of intensive management in these environments. Surprisingly, rates of vegetation change within protected areas did not differ significantly from unprotected semi‐natural vegetation. Overall, the detected LAI increases are consistent with previous, coarser‐scale, studies. The evidence indicates that woody regrowth following land abandonment is an important driver of land surface greening throughout Europe. The results offer an explanation for the large discrepancies between ESM‐derived and satellite‐derived greening estimates and thus generate new avenues for improving the ESMs on which we rely for crucial climate forecasts. The satellite record revealed substantial land surface "greening" in the northern hemisphere over recent decades, but process‐based Earth system models (ESMs) poorly reproduce observed spatial patterns of greening. Here, we show strong greening over Europe during the past 15 years. The spatial patterns of vegetation change indicate that woody regrowth following land abandonment is an important driver of land surface greening throughout Europe. The results offer an explanation for the large discrepancies between ESM‐derived and satellite‐derived greening estimates, and thus generate new avenues for improving the ESMs on which we rely for crucial climate forecasts. [ABSTRACT FROM AUTHOR]

Biomes are important constructs for organizing understanding of how the worlds' major terrestrial ecosystems differ from one another and for monitoring change in these ecosystems. Yet existing biome classification schemes have been criticized for being overly subjective and for explicitly or implicitly invoking climate. We propose a new biome map and classification scheme that uses information on (i) an index of vegetation productivity, (ii) whether the minimum of vegetation activity is in the driest or coldest part of the year, and (iii) vegetation height. Although biomes produced on the basis of this classification show a strong spatial coherence, they show little congruence with existing biome classification schemes. Our biome map provides an alternative classification scheme for comparing the biogeochemical rates of terrestrial ecosystems. We use this new biome classification scheme to analyse the patterns of biome change observed over recent decades. Overall, 13% to 14% of analysed pixels shifted in biome state over the 30-year study period. A wide range of biome transitions were observed. For example, biomes with tall vegetation and minimum vegetation activity in the cold season shifted to higher productivity biome states. Biomes with short vegetation and low seasonality shifted to seasonally moisture-limited biome states. Our findings and method provide a new source of data for rigorously monitoring global vegetation change, analysing drivers of vegetation change and for benchmarking models of terrestrial ecosystem function. [ABSTRACT FROM AUTHOR]

Aim The seasonal timing and duration of leaf deployment has major implications for earth-atmosphere interactions and biotic processes. While evidence for impacts of global change on the timing of leaf deployment (leaf phenology) is accumulating, knowledge of the mechanisms that determine the duration of leaf deployment (leaf habit) and its geographical distribution remains incomplete. Theoretical models of leaf habit assume that a selective environment leads to convergence to an optimal leaf habit. Here we examine convergence in the physiological niche of different leaf habits. Location South American, African, Indo-Pacific and Australian biogeographical realms. Methods We delineated the distribution of three phenomes: high leaf area evergreen vegetation, low leaf area evergreen vegetation and deciduous vegetation, using a 1981-2012 time series of normalized difference vegetation index (NDVI) data from the advanced very high resolution radiometer (AVHRR). For each phenome in each of the four biogeographical realms we quantified the physiological niche using a process-based model of plant growth. The derived physiological niche dimensions of each phenome in each realm were used to project its potential distribution into other, non-native, realms. Convergence in leaf habit was quantified as the level of consistency among the projections from all realms. Results The overall agreement between observed and predicted phenomes in the native realm was high (80%), suggesting that the model adequately describes the physiological niches of phenomes. Projections from each phenome into non-native realms coincided in 89% of the study area, implying widespread convergence of the physiological niches of phenomes. For the remaining 11% of the study area projections of all realms did not coincide, implying that the predicted phenome type is uncertain. Main conclusions Modelled physiological niches of the same phenome in different biogeographical realms largely overlap. This implies a dominant role for evolutionary convergence in the biogeography of leaf habit. Overall, our analysis therefore suggests that the impact of global change on the geographical distribution of leaf habit can be predicted by relatively simple physiological models. Potential explanations for non-convergence on 11% of the study area include historical contingencies and alternative stable states. [ABSTRACT FROM AUTHOR]

Small fenced reserves are perceived to require management interventions to maintain ecosystems in a natural state. Such interventions are typically initiated and assessed on the basis of short-term observations, while slow changes are often misunderstood or missed entirely. Long-term monitoring is therefore crucial to understand the effect of reserve management on ecosystem structure and functioning. We analysed a 15-year data set of herbaceous vegetation data for 59 monitoring sites in two nature reserves of different size and with different management regimes in a semi-arid, South African savanna. Community composition and vegetation structure (basal cover) were assessed in response to rainfall and management variables. No directional changes over time were found. Basal cover as measured by two proxies (distance to the nearest tuft and tuft diameter) increased with current and previous year rainfall. The relative abundance of functional groups also responded to rainfall, with perennial grasses increasing in relative abundance following a wet year. Compositional responses, as measured by a dissimilarity index of species relative abundance, showed a 2-year lag and responses were larger following dry years than wet years. The response to rainfall of distance to the nearest tuft was significantly weaker in the smaller reserve, while compositional change during dry years was larger than in the larger reserve. Synthesis and applications. Most of the variation in herbaceous basal cover and community composition was associated with differences between years (time) at each site, rather than with differences between sites (space), indicating that inter-annual variation in rainfall is the most important driver of herbaceous layer dynamics in these systems. However, management did modify the effects of rainfall on herbaceous structure and community composition. The smaller reserve, which had higher grazer and waterhole density, showed greater fluctuations in key herbaceous variables. Such reserves are common in southern Africa and probably require more careful management than larger reserves in the face of global climate change. [ABSTRACT FROM AUTHOR]