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Restoration is the human activity of manipulating vegetation with the aim of accelerating attainment of stable vegetation. But current procedures seem to arrest succession instead. A comparison of primary and secondary successions with restoration activities suggests there is little overlap in these concepts. Thinking of the process of restoration as a tertiary succession helps highlight managerial options which may improve success, especially by addressing environmental and biological legacies. [ABSTRACT FROM AUTHOR]

Premise: Root‐sprouting (RS) is an evolutionarily independent alternative to axillary stem branching for a plant to attain its architecture. Root‐sprouting plants are better adapted to disturbance than non‐RS plants, and their vigor is frequently boosted by biomass removal. Nevertheless, RS plants are rarer than plants that are not root‐sprouters, possibly because they must overcome developmental barriers such as intrinsic phytohormonal balance or because RS ability is conditioned by injury to the plant body. The objective of this study was to identify whether phytohormones or injury enable RS. Methods: In a greenhouse experiment, growth variables, root respiration, and phytohormones were analyzed in two closely related clonal herbs that differ in RS ability (spontaneously RS Inula britannica and rhizomatous non‐RS I. salicina) with and without severe biomass removal. Results: As previously reported, I. britannica is a root‐sprouter, but injury did not boost its RS ability. Root respiration did not differ between the two species and decreased continuously with time irrespectively of injury, but their phytohormone profiles differed significantly. In RS species, the auxins‐to‐cytokinins ratio was low, and injury further decreased it. Conclusions: This first attempt to test drivers behind different plant growth forms suggests that intrinsic phytohormone regulation, especially the auxins‐to‐cytokinins ratio, might be behind RS ability. Injury, causing a phytohormonal imbalance, seems to be less important in spontaneously RS species than expected for RS species in general. [ABSTRACT FROM AUTHOR]

A recent Ecology Letters paper of Fisher et al. (2008) utilized a modelling framework to investigate disturbance effects on forest biomass dynamics. But it contains serious methodological and conceptual errors. Associated conclusions are unlikely to be correct. [ABSTRACT FROM AUTHOR]

Disturbed (de‐vegetated) coastal dunes can follow divergent evolutionary pathways, evolving to one of a range of possible morphologies in response to spatial and temporal variations in windiness (i.e. the speed and direction of competent winds) or vegetation cover (i.e. the magnitude and rate of vegetation loss). Here we examine the influence of these factors on the evolution of two adjacent barriers during a sustained dune restoration programme, at Doughboy Bay, Aotearoa/New Zealand. We document a shift from a stable prograded foredune barrier to a mobile dune state over a 15‐year period. The spatial and temporal patterns of sedimentation across the barriers reflect alongshore variations in incident wind direction. Changes in vegetation resulted from an alongshore gradient in wind speed, with little decline in vegetation cover recorded towards the more sheltered sections of the dunes and almost total loss of vegetation towards the centre of the bay. Subsequent changes in vegetation cover continued to reflect these gradients in wind speed and direction, with an increase in vegetation cover associated with relatively sheltered sections of coast and a continued decline or no change in vegetation cover across the more exposed parts of the barriers. Finally, localized sediment accumulation across both barriers is strongly associated with the presence of dune‐building species. This case demonstrates the influence of wind speed, wind direction and vegetation on post‐disturbance foredune morphologies and barrier development. We propose a three‐stage conceptual model of barrier evolution consistent with existing biogeomorphic disturbance models: (1) an initial 'reaction' phase, characterized by high vegetation cover and relatively little topographic change; (2) an 'activation' phase, characterized by low vegetation cover and rapid rates of topographic change; and (3) a 'stabilization' phase, characterized by increasing vegetation cover and topographic stability. Dune restoration interventions of this type would clearly benefit from an analysis of incident wind conditions prior to commencement and careful consideration of where and how to reintroduce native sand‐binding species. [ABSTRACT FROM AUTHOR]

Increasing demand for river water now conflicts with an increasing desire to maintain riparian ecosystems. Efficiently managing river flows for riparian vegetation requires an understanding of the time scale of flow effects, but this information is limited by the absence of long‐term studies of vegetation change in response to flow variation. To investigate the influence of short‐ and long‐term flow variability and dam operation on riparian vegetation, we determined the occurrence of 107 plant species in 133 permanent plots of known inundating discharge along the Gunnison River in Colorado on five different occasions between 1990 and 2013. Individual species moved up and down the gradient of inundating discharge coincident with increases and decreases in mean annual flow, and the correlations between flow and species occurrence were strongest when flows were weighted by time before vegetation sampling with a median half‐life of 1.5 years. Some tall, rhizomatous, perennial species, however, responded to flows on a longer time scale. Logistic regression of species occurrence showed a significant relation with inundation duration for 70 out of 107 species. Plot species richness and total vegetative cover decreased in association with desiccation at low inundation durations and with fluvial disturbance at high inundation durations. Within‐plot similarity in species occurrence between years decreased strongly with increasing inundation duration. Moderate inundation durations were dominated by tall, rhizomatous, perennial herbs, including invasive Phalaris arundinacea (reed canary grass). Over the 23‐year study period, species richness declined, and the proportion of rhizomatous perennials increased, consistent with the hypothesis that decreases in flow peaks and increases in low flows caused by flow regulation have decreased establishment opportunities for disturbance‐dependent species. In summary, annual‐scale changes in vegetation were strongly influenced by flow variation, and decadal‐scale changes were influenced by decreases in fluvial disturbance from upstream flow regulation beginning decades prior to the onset of this study. [ABSTRACT FROM AUTHOR]

In the United States, national chemical water quality criteria for the protection of aquatic life assume that aquatic ecosystems have sufficient resiliency to recover from criteria exceedences occurring up to once every 3 years. This resiliency assumption was critically reviewed through two approaches: (1) synthesis of case studies, and (2) population modeling. The population modeling examined differences in recovery of species with widely different life histories. One invertebrate (Hyalella azteca) and four fish species were modeled (fathead minnow, brook trout, lake trout, and shortnose sturgeon) with various disturbance magnitudes and intervals. The synthesis of ecosystem case studies showed generally faster recoveries for insect communities rather than fish, and recoveries from pulse (acute) disturbances were often faster than recoveries from press (chronic) disturbances. When the recovery dataset excluded severe disturbances that seemed unrepresentative of common facility discharge upsets that might cause criteria exceedences, the median recovery time was 1 year, 81% of the cases were considered recovered within 3 years, and 95% were considered recovered within 10 years. The modeling projected that short‐lived fish species with high recovery times could thrive despite enduring 50% mortality disturbances every other year. However, long‐lived fish species had longer recovery times and declined under the one disturbance every 3 years scenario. Overall, the analyses did not refute the long‐standing judgements that 3 years is generally sufficient for recovery from nonrepetitive, moderate intensity disturbances of a magnitude up to 2× the chronic criteria in waters without other pollution sources or stresses. However, these constraints may not always be met and if long‐lived fish species are a concern, longer return intervals such as 5–10 years could be indicated. Environ Toxicol Chem 2022;41:2887–2910. Published 2022. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Some three‐species motifs (unique patterns of interactions between three species) are both more stable when modelled in isolation and over‐represented in empirical food webs. This suggests that these motifs may reduce extinction risk for species participating in them, ultimately stabilising the food web as a whole. We test whether a species' time to extinction following a perturbation is related to its participation in stable and unstable motifs and assess how motif roles co‐vary with a species' degree or trophic level. We found that species' motif roles are related to their times to extinction following a disturbance. Specifically, having a larger proportion of the motif role made up by the omnivory motif was associated with longer times to extinction, even though the omnivory motif is less stable than the others when modelled in isolation. While motif roles were associated with extinction risk, they also varied strongly with degree and trophic level. This means that these simpler measures of a species' role may be sufficient to roughly predict which species are most vulnerable to disturbance (though motif roles can be used to refine these predictions), but that studies of species' motif participation can also reasonably comment on vulnerability to extinction. [ABSTRACT FROM AUTHOR]

The migration phase of birds is divided into two main states: stopovers and actual migratory flights. For soaring birds, such as storks, nighttime is especially important to conserve energy and to start the next day in favourable weather conditions. Although there is a large number of recent studies on white stork Ciconia ciconia, for example using advanced technologies such as GPS technology, the nocturnal behaviour of the species is still an enigma. Thus, we GSM–GPS‐tagged 90 immature storks and checked their nocturnal behaviour, especially roost disturbance, during their first autumn migration from breeding grounds in southern Poland to wintering places in Africa. Storks roosted on three types of site: on buildings, on the ground or in trees. Birds that roosted on the ground had a higher probability of nighttime disturbance than those that used trees or buildings. The probability of disturbance at night was also related to longitude and latitude; the most easterly birds and those at the start of the migration route were disturbed more often during the night. Furthermore, and interestingly, environmental conditions at roosts were also significantly related to the probability of disturbance; birds roosting at tree sites with higher NDVI (greener) and with higher levels of artificial light both had a lower probability of disturbance. A possible explanation of this could be related to lower potential predatory pressure at night. We found that after long flights birds were disturbed more often at night, and that disturbed birds migrated further the next day. For a better understanding of the nocturnal behaviour of storks, as well as of other migratory birds, the use of modern technological tools with greater precision is recommended. [ABSTRACT FROM AUTHOR]

Weed seed predation (WSP) is an important agro‐ecosystem service that naturally suppresses weed populations. Disturbances directly interfere with the activity of the seed predators, for example, harvest and soil tillage during a peak in weed seed availability (around cereal harvest). Plant soil cover and reduced soil tillage are factors that might positively affect WSP. We investigated cover crops and living mulch along with soil disturbance (no‐till and conventional seeding) in comparison to a fallow and repeated stubble tillage with a chisel plough in terms of WSP, activity‐density of carabid beetles and soil cover. A field experiment with a randomised complete block design and four replications was conducted at two sites from 2017 until 2019. WSP rates were assessed with seed cards and exclosure cages from July until November during a period of eight consecutive days each month. Living mulch exhibited the highest WSP rates of 72% with a maximum of 95% immediately following cereal harvest in August and September of 2017 and 2019, while the remainder of the treatments ranged from 2% to 5% WSP. In October and November mustard showed on average twice as high WSP rates compared to the other treatments (50% vs. 10%–25%). Seeding and soil tillage did not significantly influence carabid beetle activity‐density and WSP, except for living mulch. Predator groups (invertebrates and vertebrates) were not influenced by the various treatments, rather year and month determined the predator groups dominance. Besides their weed suppressive effects, living mulches and cover crops also facilitate WSP. [ABSTRACT FROM AUTHOR]

Ecologists have long debated the relative importance of biotic interactions versus species‐specific habitat preferences in shaping patterns of ecological dominance. In western North America, cycles of fire disturbance are marked by transitions between North American deermice (Peromyscus maniculatus), which predominate after wildfires, and southern red‐backed voles (Myodes gapperi), which gradually replace deermice 3–4 years postfire and maintain dominance as forests mature. While this shift has been frequently documented, the processes that mediate this turnover are debated. One possibility is competitive release, which predicts a reduction in vole competition may contribute to niche expansion and population growth in deermice. Alternatively, turnover in both species may be shaped by differences in their preferred habitat and resource base, as predicted by optimum foraging theory. We evaluate these hypotheses using stable isotopes and spatial mark–recapture of deermouse and vole populations sampled prior to and following a fire as part of a longitudinal study in the Greater Yellowstone Ecosystem. Fire disturbance was associated with a 94% decrease in vole abundance but a 102% increase in deermice. Even after accounting for microhabitat, vole and deermouse populations were negatively correlated spatially and temporally (R = −0.45), and competitor abundance was more important prefire than postfire. When vole abundance was high (prefire), vole dietary niche space was seven times broader than that of deermice. Postfire, deermouse dietary niche nearly tripled and was enriched in 13C (i.e., more C4 plants), while voles occupied a slightly reduced dietary niche (79% of prefire breadth). Our results suggest deermice are experiencing ecological release due to a reduction in vole competition but vole shifts are largely driven by habitat preferences. [ABSTRACT FROM AUTHOR]

Mountain birch forest covers large areas in Eurasia, and their ecological resilience provides important ecosystem services to human societies. This study describes long‐term stand dynamics based on permanent plots in the upper mountain birch belt in SE Norway. We also present forest line changes over a period of 70 years. Inventories were conducted in 1931, 1953, and 2007. Overall, there were small changes from 1931 up to 1953 followed by a marked increase in biomass and dominant height of mountain birch throughout the period from 1953 to 2007. In addition, the biomass of spruce (Picea abies) and the number of plots with spruce present doubled. The high mortality rate of larger birch stems and large recruitment by sprouting since the 1960s reveal recurrent rejuvenation events after the earlier outbreak of the autumnal moth (Epirrita autumnata). Our results demonstrate both a high stem turnover in mountain birch and a great ability to recover after disturbances. This trend is interpreted as regrowth after a moth attack, but also long‐term and time‐lagged responses due to slightly improved growth conditions. An advance of the mountain birch forest line by 0.71 m year−1 from 1937 to 2007 was documented, resulting in a total reduction of the alpine area by 12%. Most of the changes in the forest line seem to have taken place after 1960. Regarding silviculture methods in mountain birch, a dimension cutting of larger birch trees with a cutting interval of c. 60 years seems to be a sustainable alternative for mimicking natural processes. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic transformed social and economic systems globally, including fisheries systems. Decreases in seafood demand, supply chain disruptions, and public safety regulations required numerous adaptations to maintain the livelihoods and social resilience of fishing communities. Surveys, interviews, and focus groups were undertaken to assess impacts from and adaptive responses to the pandemic in commercial fisheries in five U.S. regions: the Northeast, California, Alaska, the U.S. Caribbean, and the Pacific Islands. Fishery adaptation strategies were categorized using the Resist–Accept–Direct (RAD) framework, a novel application to understand social transformation in a social‐ecological system in response to a disturbance. A number of innovations emerged, or were facilitated, that could improve the fisheries' resilience to future disruptions. Fishers with diversified options and strategic flexibility generally fared better, i.e., had fewer disruptions to their livelihoods. Using the RAD framework to identify adaptation strategies from fishery system actors highlights opportunities for improving resilience of fisheries social‐ecological systems to future stressors. [ABSTRACT FROM AUTHOR]

With climate change increasing the magnitude and frequency of extreme precipitation events, there is a growing demand for investigations on the impacts of extreme flooding on the hydrological characteristics and vegetation of rivers, particularly in monsoonal areas. In this study, we examined multiscale relationships between hydrology, vegetation, and geomorphology after a record‐breaking flood event along the Seomjin River of South Korea in the summer of 2020. We conducted numerical modeling at the broad scale to identify the flow characteristics (e.g., depth and shear stress) of the flood event. A field survey was performed to investigate the impact of the flood on individual plants at the fine scale. The results showed widespread devastation of all vegetation types, from reed and willow communities to large, late‐successional trees taller than 10 m, which typically survive under ordinary flooding conditions. A higher threshold of shear stress was estimated for these trees (124 N m−2) than for willow (120 N m−2) and reed plants (26 N m−2), indicating that a greater level of stress is required to cause vegetation damage as ecological succession progresses. In the presence of vegetation, the average water depth increased by 9%–23% compared to the absence of vegetation. Many rivers in northeast Asia have undergone substantial vegetation expansion and succession due to the infrequency of extreme flood events. Our findings indicate that dense communities of large plants in these systems can raise the maximum water levels of flood events, thereby increasing the future flood risk to surrounding areas utilized for agriculture, transportation, industry, and housing. [ABSTRACT FROM AUTHOR]

Aims: Plant species' distribution ranges are expected to shift towards previously uncolonized locations in response to climate warming. Mountain trails, which often access to areas of special ecological value as well as remote and climatically extreme locations, could influence such shifts through changes in dispersal and disturbance. Trails may facilitate the dispersal of propagules to new locations, influence the seed bank by changing propagule input and persistence and change establishment success through the creation of gaps and disruption of biotic interactions. However, knowledge regarding the influence of mountain trails on seed rain, seed bank abundance and seedling emergence in alpine ecosystems is lacking. In this study, we examine the influence of hiking trails on dispersal patterns in mountain ecosystems. Location: Dovrefjell, Scandes mountains, Norway. Methods: We surveyed seed rain, seed bank abundance and seedling emergence along four hiking trails spanning climate gradients with a mean 2.5°C difference between warmest and coldest location at four elevations per trail and at 0.5, 7 and 17 m from the trail (48 plots, in 16 transects). Results: Seed rain was 3.4 times higher in trailside plots than in those 17 m away and declined with colder climate at all distances from trails. Seed bank abundance on trailsides at the warmest location was eight times higher than in plots at 17 m distance, while there was no significant difference at colder locations. Seedling establishment was disturbance‐driven along the whole climate gradient, with 3.5 times more seedlings on trailsides than at 17 m distance. Conclusion: Mountain trails have the potential to facilitate vegetation shifts by capturing more seed rain and creating opportunities for seedling establishment. Our findings highlight the importance of including trail effects in studies of vegetation shifts. [ABSTRACT FROM AUTHOR]

Maintaining ecosystem processes within patches of remnant vegetation is critical to minimising biodiversity loss in agricultural landscapes. Foundation species—habitat‐forming organisms that interact with many other species—are therefore a priority for conservation and restoration in farming areas. Triodia spp. grasses are foundation species of arid and semi‐arid Australia that largely depend on fire for recruitment, but fire is suppressed or excluded in many agricultural areas.We tested the effectiveness of controlled burns and competitor removal (exotic and native grasses), both in isolation and combined, on recruitment rates of Triodia scariosa in remnant vegetation using a before‐after, control‐impact study across 126 plots. A subset of plots were located in an herbivore exclusion area inside a reserve.There was no recruitment of T. scariosa 1 year after burning, regardless of treatment or control, and the burns killed all existing plants. However, T. scariosa germinated by 2 years post‐burn, with the greatest recruitment in sites where both burning and grass removal were applied. Two years after burning, T. scariosa abundance (adults and recruits) remained low outside reserves, but returned to original levels in reserves and in areas where large herbivores were excluded.Synthesis and applications. Despite failing to increase overall abundance, we show that restoration of a foundation plant species in degraded, agricultural landscapes can be achieved through a combination of fire reintroduction and competitor suppression. Germination trials from soil samples suggest a depleted seed bank limited recruitment rates, and therefore emphasise the importance of carefully timing restoration actions to overcome recruitment bottlenecks. [ABSTRACT FROM AUTHOR]

Situated in the coral triangle, the Philippines hosts some of the world's most diverse coral reefs. Yet there are few national marine protected areas (MPAs) in place that coincide with these reefs. Municipal MPAs partially alleviate this issue but a controlled comparison of the effects of different small‐scale management strategies on coral reefs is lacking.Danjugan Island Marine Reserve and Sanctuaries (DIMRS) is one of these community‐based MPAs that encompasses a collection of small (0.3–0.34 km2) marine reserves situated in a larger MPA where fishing is regulated through permits. The unique juxtaposition of different management strategies within DIMRS was used as a model system to test whether reserves are better for corals than limited fishing permits by comparing ecosystem indicators (coral cover, bleaching, disease, and morphological diversity).Total and live hard corals were 169% and 204% more abundant inside than outside no‐take zones in 2016. This distinction increased between 2002 and 2016 as a result of a more marked decrease in coral cover over time in the partially protected zones. A 70% higher coral community evenness outside the reserves further suggests that scleractinian coral communities on fished reefs are more disturbed.Live coral cover within the MPAs of DIMRS in 2016 (39 ± 4%) is above the current mean for Philippine reefs (23%) and is comparable with the long‐term average for reefs situated within Philippine MPAs (36%). This study suggests that exceptionally small reserves may benefit hard corals more than regulation via fishing permits. [ABSTRACT FROM AUTHOR]

We introduce a new approach—acoustic restoration—focusing on the applied utility of soundscapes for restoration, recognising the rich ecological and social values they encapsulate. Broadcasting soundscapes in disturbed areas can accelerate recolonisation of animals and the microbes and propagules they carry; long duration recordings are also ideal sources of data for benchmarking restoration initiatives and evocative engagement tools. [ABSTRACT FROM AUTHOR]

Fire refugia and patchiness are important to the persistence of fire‐sensitive species and may facilitate biodiversity conservation in fire‐dependent landscapes. Playing the role of ecosystem engineers, large herbivores alter vegetation structure and can reduce wildfire risk. However, herbivore effects on the spatial variability of fire and the persistence of fire‐sensitive species are not clear. To examine the hypothesis that large herbivores support the persistence of fire‐sensitive species through the creation of fire refugia in fire‐prone landscapes, we examined the response of a fire‐sensitive plant, Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis [Beetle & Young]) to fire and grazing in the fire‐dependent mixed‐grass prairie of the northern Great Plains. We carried out a controlled burn in 2010 within pre‐established exclosures that allowed differential access to wild and domestic herbivores and no record of fire in the previous 75 years due to fire suppression efforts. The experiment was set up with a split‐plot design to also examine potential changes in plots that were not burned. Canopy cover of big sagebrush was recorded before the burn in 2010 and again in 2011 with percent area burned recorded within 1‐month post‐fire in the burned plots. Percentage area burned was the greatest in ungulate exclosures (92% ± 2%) and the least in open areas (55% ± 21%), suggesting that large herbivores influenced fire behavior (e.g., reducing fire intensity and rate of spread) and are likely to increase fire patchiness through their alterations to the fuel bed. Regression analysis indicated that the proportion of sagebrush cover lost was significantly correlated with the proportion of area burned (R2 = 0.76, p = 0.05). No differences in the non‐burn plots were observed among grazing treatments or among years. Altogether, this illustrates the potential importance of large herbivores in creating biotic‐driven fire refugia for fire‐sensitive species to survive within the flammable fuel matrix of fire‐dependent grassland ecosystems such as the mixed‐grass prairie. Our findings also attest to the resiliency of the northern Great Plains to fire and herbivory and underscore the value of managing grasslands for heterogeneity with spatial and temporal variations in these historic disturbances. [ABSTRACT FROM AUTHOR]

Aim: The presence and use of trails may change plant species' realized climatic niches via modified abiotic and biotic conditions including propagule transport, allowing competition‐pressed alpine species to expand their rear edges towards warmer locations and lowland species to extend their leading edges towards cooler locations. We investigated whether mountain trails indeed act as corridors for colonization and shift species' realized climatic niches, resulting in higher species richness in trailsides. Location: Dovrefjell and Abisko area in the Scandes mountains of Norway and Sweden. Methods: We surveyed plant community composition and disturbances along 16 hiking trails in summer 2018 (Dovrefjell) and 2019 (Abisko). We linked changes in species' realized climatic niches to their climatic optimum and variation in species richness to climate, trail effects and resident plant community characteristics. Results: Plant species richness was on average 24% greater in trailside than in interior vegetation plots. Proximity to trails accounted for 9% and climatic harshness for 55% of variation in species richness explained in our model. Trailsides increased in richness, especially in relatively species‐poor sites and close to introduction points (each accounting for 24% of variation in our model of species gains). Shifts in rear edges and optima of realized climatic niches along trails related to species' undisturbed climatic optimum, with alpine species being more likely to move into warmer locations. While some disturbance‐associated species shifted their leading edges towards colder locations, contrary to expectations this was not the case for lowland species. Overall, shifts in climatic niches resulted in more species' niches overlapping in trailsides than in the interior vegetation. Main conclusion: Trails can locally increase species richness by creating opportunities for colonizing species and weaker competitors. Because of prevailing disturbance, they may even provide opportunities for persistence and downward expansion of alpine species, aiding conservation efforts. [ABSTRACT FROM AUTHOR]

Understanding how ecosystem functioning is impacted by global change drivers is a central topic in ecology and conservation science. We need to assess not only how environmental change affects species richness, but also how the distribution of functional traits (i.e. functional diversity) mediate the relationship between species richness and ecosystem functioning. However, most evidence about the capacity of functional diversity to explain ecosystem functioning has been developed from studies conducted at a single spatial scale. Here, we explore theory, expectations and evidence for why and how species richness and functional diversity relationships vary with spatial scale. Despite the importance of accounting for spatial processes at multiple scales, we show that most studies of the species richness–functional diversity relationship focus on single scale analyses that ignore spatial context. Thus, we discuss the need to establish a spatially explicit, multi‐scale framework for understanding the relationship between species richness and functional diversity. As a starting point to developing such a framework, we detail some expected trajectories and mechanisms by which the diversity of species and functional traits may change across increasing spatial scales. We also explore what is known about two important gaps in the literature about this relationship: 1) the influence of spatial autocorrelation on community assembly processes and 2) the variation in the structure of species interactions across spatial extents. We present some key challenges that could be addressed by integrating approaches from community and landscape ecology. This information will help improve our understanding of the relative influence of local and large‐scale processes on community structure, while providing a foundation for improving biodiversity monitoring, policy and ecosystem function based conservation. [ABSTRACT FROM AUTHOR]

Forests are currently a substantial carbon sink globally. Many climate change mitigation strategies leverage forest preservation and expansion, but rely on forests storing carbon for decades to centuries. Yet climate‐driven disturbances pose critical risks to the long‐term stability of forest carbon. We quantify the climate drivers that influence wildfire and climate stress‐driven tree mortality, including a separate insect‐driven tree mortality, for the contiguous United States for current (1984–2018) and project these future disturbance risks over the 21st century. We find that current risks are widespread and projected to increase across different emissions scenarios by a factor of >4 for fire and >1.3 for climate‐stress mortality. These forest disturbance risks highlight pervasive climate‐sensitive disturbance impacts on US forests and raise questions about the risk management approach taken by forest carbon offset policies. Our results provide US‐wide risk maps of key climate‐sensitive disturbances for improving carbon cycle modeling, conservation and climate policy. [ABSTRACT FROM AUTHOR]

Accelerating rates of biodiversity loss underscore the need to understand how species achieve resilience—the ability to resist and recover from a/biotic disturbances. Yet, the factors determining the resilience of species remain poorly understood, due to disagreements on its definition and the lack of large‐scale analyses. Here, we investigate how the life history of 910 natural populations of animals and plants predicts their intrinsic ability to be resilient. We show that demographic resilience can be achieved through different combinations of compensation, resistance and recovery after a disturbance. We demonstrate that these resilience components are highly correlated with life history traits related to the species' pace of life and reproductive strategy. Species with longer generation times require longer recovery times post‐disturbance, whilst those with greater reproductive capacity have greater resistance and compensation. Our findings highlight the key role of life history traits to understand species resilience, improving our ability to predict how natural populations cope with disturbance regimes. [ABSTRACT FROM AUTHOR]

Hurricanes and other extreme events are increasing in many regions, yet their long‐term impacts on ecosystem function are uncertain. In forested ecosystems, soil solution chemistry provides an important tool to assess the impacts of disturbance on nutrient cycling and dissolved organic carbon dynamics. Here, we address the dependence of soil solution chemistry on disturbance regime using a novel combination of both experimental and observational results collected over a period of 16 years in montane tropical sites in the Luquillo Experimental Forest of Puerto Rico. Soil solution was sampled following various combinations of canopy trimming and detrital manipulation (2004), repeated manipulation (2014), drought (2015), and Hurricane Maria (2017). Soil solution was sensitive to disturbance but resilient, with return to baseline after 12–18 months. Any disturbance regime that involved loss of canopy and detrital inputs to the forest floor resulted in increased nitrate concentrations, but the response declined with repeated disturbance. Lysimeters in plots that had received no experimental manipulation had 1.5 times higher response to Hurricane Maria than those previously manipulated. The response to disturbance thus showed clear context dependence, with disturbance history affecting disturbance response. Among the nutrients and major ions, only nitrate showed a response to experimental manipulations, drought, and Hurricane Maria. In contrast to nitrate, soil solution potassium was unaltered by initial experimental manipulation but increased dramatically following drought and Hurricane Maria. Phosphorus only increased following Hurricane Maria and only in plots that had twice received experimental trimming and deposition of cut branches on the forest floor. Stoichiometry of dissolved organic matter also changed in these plots, with decreased carbon to nitrogen ratios. The potassium response suggests that damage to roots from tropical cyclones and drought is an important driver of the biogeochemical response to tropical storms. Dampening of soil nitrogen losses and increases in phosphorus losses following successive disturbance events indicates that increased frequency of tropical storms and droughts will result in fundamental alteration of soil biogeochemical cycles, with uncertain effects on forest structure. [ABSTRACT FROM AUTHOR]

In 2020, the Australian and New Zealand flux research and monitoring network, OzFlux, celebrated its 20th anniversary by reflecting on the lessons learned through two decades of ecosystem studies on global change biology. OzFlux is a network not only for ecosystem researchers, but also for those 'next users' of the knowledge, information and data that such networks provide. Here, we focus on eight lessons across topics of climate change and variability, disturbance and resilience, drought and heat stress and synergies with remote sensing and modelling. In distilling the key lessons learned, we also identify where further research is needed to fill knowledge gaps and improve the utility and relevance of the outputs from OzFlux. Extreme climate variability across Australia and New Zealand (droughts and flooding rains) provides a natural laboratory for a global understanding of ecosystems in this time of accelerating climate change. As evidence of worsening global fire risk emerges, the natural ability of these ecosystems to recover from disturbances, such as fire and cyclones, provides lessons on adaptation and resilience to disturbance. Drought and heatwaves are common occurrences across large parts of the region and can tip an ecosystem's carbon budget from a net CO2 sink to a net CO2 source. Despite such responses to stress, ecosystems at OzFlux sites show their resilience to climate variability by rapidly pivoting back to a strong carbon sink upon the return of favourable conditions. Located in under‐represented areas, OzFlux data have the potential for reducing uncertainties in global remote sensing products, and these data provide several opportunities to develop new theories and improve our ecosystem models. The accumulated impacts of these lessons over the last 20 years highlights the value of long‐term flux observations for natural and managed systems. A future vision for OzFlux includes ongoing and newly developed synergies with ecophysiologists, ecologists, geologists, remote sensors and modellers. [ABSTRACT FROM AUTHOR]

Boreal forests cover over half of the global permafrost area and protect underlying permafrost. Boreal forest development, therefore, has an impact on permafrost evolution, especially under a warming climate. Forest disturbances and changing climate conditions cause vegetation shifts and potentially destabilize the carbon stored within the vegetation and permafrost. Disturbed permafrost‐forest ecosystems can develop into a dry or swampy bush‐ or grasslands, shift toward broadleaf‐ or evergreen needleleaf‐dominated forests, or recover to the pre‐disturbance state. An increase in the number and intensity of fires, as well as intensified logging activities, could lead to a partial or complete ecosystem and permafrost degradation. We study the impact of forest disturbances (logging, surface, and canopy fires) on the thermal and hydrological permafrost conditions and ecosystem resilience. We use a dynamic multilayer canopy‐permafrost model to simulate different scenarios at a study site in eastern Siberia. We implement expected mortality, defoliation, and ground surface changes and analyze the interplay between forest recovery and permafrost. We find that forest loss induces soil drying of up to 44%, leading to lower active layer thicknesses and abrupt or steady decline of a larch forest, depending on disturbance intensity. Only after surface fires, the most common disturbances, inducing low mortality rates, forests can recover and overpass pre‐disturbance leaf area index values. We find that the trajectory of larch forests after surface fires is dependent on the precipitation conditions in the years after the disturbance. Dryer years can drastically change the direction of the larch forest development within the studied period. Plain Language Summary: Boreal forests of eastern Siberia, cover more than half of the global permafrost area and insulate the underlying frozen ground. The development of the forest cover is important for the state and evolution of permafrost. Forest disturbances such as fires or droughts and climate change can cause changes in this ecosystem. Potentially such shifts can destabilize the carbon stored within the vegetation and permafrost. Disturbed permafrost‐forest ecosystems can develop into the dry or swampy bush‐ or grasslands, shift toward different forest types, or recover. An increase in the number and intensity of fires, as well as intensified logging, could lead to partial or complete permafrost degradation. We study the interactions between forest disturbances, permafrost, and forests. We use a forest‐permafrost model and simulate disturbances at a study site in eastern Siberia. We implement mortality, defoliation, and ground surface changes of different disturbances. We then analyze the forest recovery's impact on the permafrost underneath. We find that forest loss can cause soil drying and abrupt or steady decline of forests, depending on the intensity of the disturbance. Only after a surface fire, which has low mortality rates and is the most common disturbance, forests can successfully recover. Key Points: We demonstrate a dynamic forest‐permafrost model to investigate the interplay between boreal larch forest, permafrost, and disturbancesForest loss induces soil drying which leads to lower active layer thicknesses and abrupt or steady decline of larch forest coverTrajectory of larch forests after surface fires is dependent on the post‐disturbance precipitation conditions [ABSTRACT FROM AUTHOR]

Australian forest ecosystems cover almost 16% of Australia's landmass. As the seventh‐largest forested area worldwide, these forest ecosystems have largely evolved in the face of a changing climate and fire regime, drought and human land use practice. Australian tree ferns contribute to both the unique biodiversity of these forests and current forest product markets. We review the Australian tree fern literature including: the importance of tree ferns for other components of biodiversity; their response to disturbance such as fire and silviculture; and the management of tree ferns as a product for the horticultural market. Most studies focused on tree fern response to wildfire and clearfell burn and sow logging following management and horticultural industry changes. Survival and recruitment of tree ferns after a single fire/logging disturbance event found short‐lived negative impacts. Studies of tree ferns over time include research on growth, with non‐linear growth models found to best describe tree fern age; Cyathea australis grows 2.2 ‐ 4.0 times faster than Dicksonia antarctica on average. Tree ferns perform a keystone function through habitat for epiphytes at the local scale, but it is unknown if this has an impact on biodiversity at the landscape scale. Our review found few studies on survival and recruitment following drought; multiple disturbance events such as repeated logging; and silvicultural techniques other than clearfell burn and sow. No studies had investigated the response of tree ferns to changing climate, invasive species, changes in fire frequency or effect of megafire. We conclude with recommendations for key areas of research including, future impacts due to changing climate, synecology, influence on forests, the impact of silvicultural techniques and the influence of megafires on survival. [ABSTRACT FROM AUTHOR]

On a warming planet, a key challenge natural resource managers face is protecting wildlife while mitigating climate change—as through forest carbon storage—to the greatest extent possible. But in some ecosystems, habitat restoration for imperiled species may be incompatible with maximizing carbon storage. For example, promoting early successional forest conditions does not maximize stand‐level carbon storage, whereas uniformly promoting high stocking or mature forest conditions in the name of carbon storage excludes species that require open or young stands. Here, we briefly review the literature regarding carbon and wildlife trade‐offs and then explore four case studies from the Northern Forest region of the United States. In each case, human activities have largely dampened the influence of natural disturbances; restoring or emulating these disturbances is typically required for habitat restoration even when doing so equates to less carbon storage at the stand level. We propose that applying a climate adaptation lens can help managers and planners navigate these trade‐offs and steer away from maladaptive practices that may ultimately reduce adaptive capacity. Instead, critically evaluating the consequences of stand‐level management actions on both carbon and wildlife can then facilitate landscape‐scale climate adaptation planning that supports a diversity of habitats alongside opportunities to invest in maximizing forest carbon. [ABSTRACT FROM AUTHOR]

People seek reliable natural resources despite climate change. Diverse habitats and biologies stabilize productivity against disturbances like climate, prompting arguments to promote climate‐resilient resources by prioritizing complex, less‐modified ecosystems. These arguments hinge on the hypothesis that simplifying and degrading ecosystems will reduce resources' climate resilience, a process liable to be cryptically evolving across landscapes and human generations, but rarely documented. Here, we examined the industrial era (post 1848) of California's Central Valley, chronicling the decline of a diversified, functional portfolio of salmon habitats and life histories and investigating for empirical evidence of lost climate resilience in its fishery. Present perspectives indicate that California's dynamic, warming climate overlaid onto its truncated, degraded habitat mosaic severely constrains its salmon fishery. We indeed found substantial climate constraints on today's fishery, but this reflected a shifted ecological baseline. During the early stages of a stressor legacy that transformed the landscape and ‐‐ often consequently ‐‐ compressed salmon life history expression, the fishery diffused impacts of dry years across a greater number of fishing years and depended less on cool spring‐summer transitions. The latter are important given today's salmon habitats, salmon life histories, and resource management practices, but are vanishing with climate change while year‐to‐year variation in fishery performance is rising. These findings give empirical weight to the idea that human legacies influence ecosystems' climate resilience across landscapes and boundaries (e.g., land/sea). They also raise the question of whether some contemporary climate effects are recent and attributable not only to increasing climate stress, but to past and present human actions that erode resilience. In general, it is thus worth considering that management approaches that prioritize complex, less‐modified ecosystems may stabilize productivity despite increasing climate stress and such protective actions may be required for some ecological services to persist into uncertain climate futures. [ABSTRACT FROM AUTHOR]

Peatland functions (e.g., carbon sequestration and flora diversity) are largely driven by soil moisture dynamics and thus dependent on interactions between hydrologic regimes and organic soil properties. Understanding these interactions is particularly important in drained peatlands, where drier conditions may alter soil properties with feedbacks to soil water retention and associated ecosystem functions. In this work, we focused on the Great Dismal Swamp (GDS) in Virginia, USA, a historically drained, temperate peatland with ongoing hydrologic restoration efforts. Two distinct soil layers varying in thickness exist at GDS: an upper layer with subangular blocky structure thought to be a result of past drainage, and a sapric lower layer with a massive structure more representative of an undisturbed state. To understand the occurrence and consequences of these distinct layers, we used continuous water table data and analysed soil physical and hydraulic properties to characterize soil profiles at 16 locations. We found significant differences between layer properties, where upper layers had lower fibre and organic matter contents and higher bulk densities. Further, moisture release curves demonstrated lower water retention in upper layers compared with lower layers and key differences in pore structure, with upper layers having higher macroporosity. Upper layers varied in thickness across sampling locations (~0.30 to 1.0 m) with a transition to lower soil layers typically occurring at depths below contemporary water level observations, suggesting that the upper layer may be a result of historical drainage and deeper water table conditions. Yet, upper layers with more frequent saturation exhibited higher water retention and lower macroporosity compared with drier upper layers, thus indicating potential recovery following re‐wetting efforts. These findings highlight how past drainage influences soil properties and water retention, with important implications for current management objectives at GDS and other drained peatland systems. [ABSTRACT FROM AUTHOR]

Disturbance of marine sediments results in the remineralization of sedimentary organic matter (OM) and impacts upon natural burial processes. Management interventions which restrict or remove activities that cause seabed disturbance may offer effective strategies to protect the most vulnerable of these shelf sea OM stores, offering new opportunities to deliver climate mitigation actions. While the largest quantities of OM are often stored in the expansive offshore regions of continental shelves and might therefore suggest appropriate zones for management interventions to protect vulnerable OM stores, our results highlight that these offshore regions generally contain OM of low reactivity. Conversely, inshore and coastal sediments store significant quantities of highly reactive OM that is at greater risk of remineralization when disturbed. The marked spatial disparities between OM reactivity across shelf sea sedimentary environments highlights the need to focus emergent policy and future management interventions toward the protection of inshore and coastal sediments. Plain Language Summary: If disturbed, the organic carbon within seafloor sediments can potentially be converted to carbon dioxide and a portion lost to the atmosphere, where it potentially contributes to climate change. Our results highlight that the reactivity (biodegradability) of sedimentary carbon across shelf seas is highly variable with low reactivity organic matter found in the offshore region, while organic matter within inshore and coastal sediments can be highly reactive and potentially vulnerable to break‐down when disturbed. These differences in organic matter reactivity highlight the need to focus emergent management interventions that can deliver protection toward the most vulnerable organic matter stores in inshore and coastal sediments. Key Points: Within most shelf sediments organic matter (OM) is generally of low reactivity (i.e., low labile OM content) and resistant to remineralizationMuddy nearshore sediments hold large quantities of high reactivity OM which is at risk of remineralization when disturbedPolicy interventions that seek to protect reactive OM should prioritize near‐shore sediment OM over the resilient OM in many shelf seas [ABSTRACT FROM AUTHOR]

Earth's rapidly warming climate is propelling us towards an increasingly fire‐prone future. Currently, knowledge of the extent and characteristics of animal mortality rates during fire remains rudimentary, hindering our ability to predict how animal populations may be impacted in the future. To address this knowledge gap, we conducted a global systematic review of the direct effects of fire on animal mortality rates, based on studies that unequivocally determined the fate of animals during fire. From 31 studies spanning 1984–2020, we extracted data on the direct impacts of fire on the mortality of 31 species from 23 families. From these studies, there were 43 instances where direct effects were measured by reporting animal survival from pre‐ to post‐fire. Most studies were conducted in North America (52%) and Oceania (42%), focused largely on mammals (53%) and reptiles (30%), and reported mostly on animal survival in planned (82%) and/or low severity (70%) fires. We found no studies from Asia, Europe or South America. Although there were insufficient data to conduct a formal meta‐analysis, we tested the effect of fire type, fire severity, fire regime, animal body mass, ecological attributes and class on survival. Only fire severity affected animal mortality, with a higher proportion of animals being killed by high than low severity fires. Recent catastrophic fires across the globe have drawn attention to the plight of animals exposed to wildfire. Yet, our systematic review suggests that a relatively low proportion of animals (mean predicted mortality [95% CI] = 3% [1%–9%]) are killed during fire. However, our review also underscores how little we currently know about the direct effects of fire on animal mortality, and highlights the critical need to understand the effects of high severity fire on animal populations. [ABSTRACT FROM AUTHOR]

Aim: The effects of fires on vertebrate scavengers have not been characterized despite the importance of scavenging in shaping food web dynamics. We assessed whether the 2019/2020 megafires in Australia shifted the species richness, carcass detection and feeding times of vertebrate scavengers, and whether the fire affected carcasses persistence times. Location: Blue Mountains, south‐eastern Australia. Method: We monitored vertebrate scavengers via remote cameras on a total of 60 experimentally placed kangaroo carcasses for 30 days in two periods before the megafire (January 2018 and 2019) and one period after the megafire (March 2020) in both open and closed canopy habitats. We compared vertebrate species richness, carcass discovery and scavenging activity before and after the fire and between the two habitats. We also assessed carcass persistence (time to carcass removal) before and after the fire and between the two habitats. Results: We collected more than 689,000 images of nine vertebrate scavengers including six avian, two mammal and one reptile species. We detected no decline in scavenger species richness following the fire, and rates of carcass detection for mammals and reptiles did not differ across pre‐ and post‐fire periods. On the other hand, avian scavengers detected carcasses faster in the post‐fire period and in open compared to closed canopy habitats. Overall, scavengers increased their feeding times in the post‐fire period, especially avian scavengers, but carcasses persisted longer in the post‐fire period when compared to the second pre‐fire period. Main conclusion: Our study identified that a widespread fire could influence avian scavenging dynamics, but that other factors such as habitat and possibly apex scavenger presence affected carcass persistence times over the study period in addition to fire. Future monitoring of carcasses following fires should focus on the responses by both vertebrate and insect scavengers to fully elucidate the effects of these major disturbance events on critical ecosystem processes linked to decomposition. [ABSTRACT FROM AUTHOR]

Aim: As climate change intensifies and wildfire frequency and scale increase, it is critical we develop a robust understanding of how species recover from these major disturbances. Here, we aim to determine whether source populations for recovery following large‐scale intense wildfires are derived from either in situ survival, or immigration from surrounding unburnt areas (ex situ). Secondly, we sought to determine whether habitat elements (e.g., logs) within the landscape facilitate in situ survival of small mammals during fires. Location: Grampians National Park, south‐eastern Australia. Methods: We used long‐term post‐fire small mammal monitoring to investigate sources of recovery for small mammals, and camera trapping and habitat surveys immediately following large intense wildfires to assess evidence for and drivers of post‐fire survival. Results: We found no relationship between distance to unburnt vegetation and the occurrence of any native species, suggesting that in situ survival is the probable mechanism for recovery of post‐fire mammal populations, compared with immigration from external unburnt areas. We also show that key habitat elements such as rocks and large trees were associated with the occurrence of several species immediately post‐fire, suggesting a role for these features in facilitating the survival of species during and following fire. Main conclusions: We present evidence for post‐fire recovery being driven by in situ survival. In situ survival is facilitated by small unburnt patches and habitat elements in burnt areas. These surviving individuals become the founders for subsequent post‐fire population recovery. Given that globally we are seeing increasingly frequent large‐scale wildfires driven by climate change, the capacity for in situ survival will help mitigate some of the fire‐related impacts of climate change. [ABSTRACT FROM AUTHOR]

Fires increasingly impact forested watersheds, with uncertain water resources impacts. While research has revealed higher peak flows, longer‐term yields may increase or decrease following fire, and the mechanisms regulating post‐fire streamflow are little explored. Hydrologic response to disturbance is poorly understood in the Lower Colorado River Basin (LCRB), where snowmelt often occurs before the growing season. Here, we quantify annual streamflow changes following what have been, before 2020, two of the largest wildfires in the modern history of the contiguous United States. We evaluate nine nested watersheds with >50 years records within the Salt River Basin to evaluate fire impact over ranges of elevation, climate, vegetation, burned area, and spatial scale. We employ double‐mass comparison of paired watersheds, pre‐ and post‐fire runoff ratio comparison, multiple linear regression of climate and fire, and time‐trend analysis. Precipitation and streamflow are decoupled during dry periods; therefore we conduct separate change detection for wet and dry periods. Post‐fire summer streamflow increased by 24%–38% at all elevations. While winter/spring streamflow remained constant in the highest, coldest headwaters, winter flows declined in lower‐elevation headwaters. As a result, basin annual streamflow declined. These results support emerging understanding that warm semiarid watersheds respond differently to disturbance than well‐studied, colder watersheds. Asynchrony between winter snowmelt and summer evaporative demand is likely important when considering long‐term impacts of forest management and disturbance on water supply in the LCRB. Plain Language Summary: Wildfire is increasingly common and severe in many of the forested watersheds important for water supplies. Following fire, there is an increased risk of short‐term flooding. However, we do not understand how wildfire changes the amount of water flowing out of a watershed over multiple years. Although wildfire leaves fewer trees to take up water, it also destroys the shade from sun and wind which protects snowpack and soil moisture from evaporation. Here, we made side‐by‐side comparisons and before‐after comparisons to determine wildfire impacts on the multiyear streamflow from nine watersheds of the Salt River Basin in Arizona. We found that streamflow increased in summer. While the much larger winter/spring streamflow did not change much at high elevations, it declined in lower‐elevation watersheds following fire. One reason for this difference might be that at high elevation, the snow melts at the start of the summer growing season, when trees are likely to take up the water. Wildfire reduces trees and thereby increases streamflow. At lower elevations, snow melts much earlier in the year, when trees are not active, making the water savings from burned forests less important. These results suggest that lower, warmer forested watersheds may produce less streamflow following wildfire. Key Points: Summer streamflow increased in headwaters at all elevations following fireDominant winter/spring streamflow was unchanged in higher/colder headwaters but decreased in lower/warmer headwatersClimatological asynchrony of snowmelt and transpiration in warmer watersheds may reduce streamflow benefits of fire [ABSTRACT FROM AUTHOR]

The current research is unclear regarding the sensitivity of the output of a magnetic flowmeter analysis to the fidelity of the simulated flow field. This study evaluates the effects of higher fidelity models on magnetic flowmeter analysis. An eddy viscosity model, second‐moment closure model, and a Large‐Eddy simulation were compared to laboratory velocity profile data 0.67D downstream of a 1.58D elbow at a Reynolds number of 34,000. The Large‐Eddy simulation results matched the laboratory velocity profile data best. The authors conclude that the fidelity of the flow field model does cause differences in the analysis of the flowmeter voltage output. [ABSTRACT FROM AUTHOR]

Environmental rehabilitation is mandatory for mining operations in many countries, including Lesotho. At Letšeng Diamond Mine in Lesotho, waste residues of kimberlite tailings create a hostile environment for the establishment of plant species during vegetation restoration. In this study, we investigated seed germination of native grassland species and tested the best performing species on different topsoil mixtures with kimberlite tailings in the Afro‐alpine zone in Lesotho. Rapid germination tests showed highly significant differences in the number of seedlings that emerged for different plant species: the grass Tenaxia disticha (% mean ± SE: 80 ± 17%; n = 36) and the forb Hesperantha schelpeana (56 ± 14%) were highest but nonsignificantly different to each other, while other species were significantly lower and nonsignificantly different to each other. In all treatments, seed germination of T. disticha was significantly higher than the experimental control, while the treatments that were covered with topsoil did not differ significantly. In addition, T. disticha seedling height and basal width varied significantly over time with seedlings in all the treatments growing significantly taller than those in the experimental control. Also, seedling basal width showed significant increase during the third growing season while height remained constant. We concluded that kimberlite tailings ameliorated with topsoil encourage plant establishment and performance of T. disticha, and this medium could be used to stabilize disturbed mine landscapes in the Afro‐alpine zone of Lesotho. [ABSTRACT FROM AUTHOR]

Succession is a basic natural process of ecosystem recovery, it may start completely de novo (primary succession) or after serious disturbance of the previous ecosystem (secondary succession). Despite most reclamation and restoration approaches depending on it and despite extensive previous research, we found no worldwide review that would describe the pattern of vegetation cover and woody vegetation recovery in individual types of succession and explore major factors that affect the speed of vegetation recovery. To fill this gap we have searched world literature and extracted data about 244 succession series about total vegetation cover and 113 about woody vegetation cover. The rate of vegetation cover recovery is significantly slower during primary succession than during secondary succession, this however not apply to woody vegetation. The type of disturbance affects the speed of recovery, post‐mining sites recover fastest among primary succession and older fields were the fastest among secondary succession, the slowest one being succession in glacier retreats. Latitude, soil pH, the size of the disturbed area, temperature, and actual evapotranspiration affect the rate of vegetation recovery in primary succession, while only latitude affects secondary succession. Some other factors affect succession after a specific disturbance. The study shows that succession can be an effective tool to restore vegetation cover and woody vegetation on many occasions. We expect that differences in the nutrient availability determine differences in the rate of total vegetation cover recovery, while soil porosity (compaction) may be an important factor affecting woody vegetation recovery. [ABSTRACT FROM AUTHOR]

This article studies the fixed‐time tracking consensus of second‐order nonlinear multi‐agent systems with disturbance. To make the fixed‐time tracking consensus, a consensus protocol based on the integral sliding mode surface is proposed, which can ensure the adjacent agents remain within a limited communication range in the communication process. By adopting Lyapunov stability theory and matrix theory, sufficient conditions for the fixed‐time tracking consensus are given, and a bound of the settling time is obtained. Finally, a simulation example is presented to verify the potential correctness of the obtained results. [ABSTRACT FROM AUTHOR]

Aim: Tropical old‐growth grasslands are increasingly acknowledged as biodiverse ecosystems, but they are understudied in many aspects. Geoxyle species are a key component in many of these ecosystems, their belowground storage organs and bud banks are functionally diverse and contribute to the grasslands' resilience. However, the drivers of the geoxyles' evolution and (belowground) diversity are little understood. Thus, we combined analyses on the key aspects of diversity, belowground functionality, ancestry, and ecology of geoxyles to provide the first comprehensive understanding of this often overlooked growth form. Location: Southern hemisphere Africa, particularly Angola as a part of the Zambezian phytochorion. Taxon: Geoxyle species. Methods: We assessed belowground bud bank types and biogeographic origins of geoxyles in grass‐dominated vegetation types on the Angolan plateau, covering a broad altitudinal, climatic and geological range. Geoxyles were sampled extensively at three different sites, yielding 118 taxa covering about 59% of the Angolan geoxyle flora. Based on the current distribution of these species in Africa below the equator, we analysed their origins and environmental correlates in a taxonomic, functional and biogeographic context. Results: Geoxyle species numbers and species communities differed strongly among sites, but functional types showed very similar spectra. Geoxyles evolved in multiple lineages and originated in different biomes, and functional types were unevenly associated with lineages and biomes. Furthermore, functional types correlate to specific environmental driver combinations. Main conclusions: Functional diversity is not directly linked to species diversity, but is a result of multiple biogeographic origins that contributed functionally differently preadapted lineages to the Zambezian flora. Thus, geoxyles can occur under different environmental conditions, but require seasonal climates, and open grassy ecosystems subjected to fire, frost and likely herbivory. We highlight the importance of frost as a correlate of geoxyle diversity and emphasize the need for further studies to understand this important and complex growth form. [ABSTRACT FROM AUTHOR]

Emergency conservation interventions will be increasingly necessary to prevent extinctions or severe population bottlenecks as extreme events become more frequent. We detail the emergency extraction of the endangered Eastern Bristlebird (Dasyornis brachpterus) during the unprecedented 2019–2020 Australian Black Summer bushfires, an intervention that led to the rapid establishment of a temporary ex situ insurance population sourced from an area under immediate threat from bushfire (Croajingolong National Park, Victoria). The intervention was triggered, coordinated, and implemented within a 4‐week period, with re‐release to the wild within 2 months. We present this case study within a framework for emergency conservation interventions, based on the emergency management phases of preparation, response, and recovery, with the addition of an evaluation phase. The preparation phase involved compiling existing knowledge and capacity to facilitate the operation. The response phase consisted of (a) initiation and planning of the intervention (coordination) and (b) implementation, that is, the translocation of 15 birds from an area under threat of bushfire to a captive institution (>500 km). The recovery phase saw the insurance population re‐released to unburnt habitat after the bushfire had ceased. The evaluation phase incorporated lessons learnt from the other three phases as part of an adaptive management approach. We reflect on the Eastern Bristlebird emergency conservation intervention to explore how we can better prepare for, respond to, and recover from the large range of emergencies faced by biodiversity around the world. [ABSTRACT FROM AUTHOR]

Remote coral reefs are thought to be more resilient to climate change due to their isolation from local stressors like fishing and pollution. We tested this hypothesis by measuring the relationship between local human influence and coral community resilience. Surprisingly, we found no relationship between human influence and resistance to disturbance and some evidence that areas with greater human development may recover from disturbance faster than their more isolated counterparts. Our results suggest remote coral reefs are imperiled by climate change, like so many other geographically isolated ecosystems, and are unlikely to serve as effective biodiversity arks. Only drastic and rapid cuts in greenhouse gas emissions will ensure coral survival. Our results also indicate that some reefs close to large human populations were relatively resilient. Focusing research and conservation resources on these more accessible locations has the potential to provide new insights and maximize conservation outcomes. [ABSTRACT FROM AUTHOR]

Motivation: Rapid climate change is altering plant communities around the globe fundamentally. Despite progress in understanding how plants respond to these climate shifts, accumulating evidence suggests that disturbance could not only modify expected plant responses but, in some cases, have larger impacts on compositional shifts than climate change. Climate‐driven disturbances are becoming increasingly common in many biomes and are key drivers of vegetation dynamics at both species and community levels. Palaeoecological records provide valuable observational windows for elucidating the long‐term impacts of these disturbances on plant dynamics; however, sparse resolution and difficulty in disentangling drivers of change limit our ability to understand the impact of disturbance on plant communities. In this targeted review, we highlight emerging opportunities in palaeoecology to advance our understanding about how disturbance, especially fire, impacts the ecological and evolutionary dynamics of terrestrial plant communities. Location: Global examples, with many from North America. Conclusions: We propose a set of palaeoecological and integrative approaches that could greatly enhance our understanding of how disturbance regimes influence global plant dynamics. Specifically, we identify four future study areas: (1) focus on palaeoecological disturbance proxies beyond fire and leverage multi proxy research to examine the influence of interacting disturbances on plant community dynamics; (2) use advances in disturbance and vegetation reconstructions, including ancient sedimentary DNA, to provide the spatial, temporal and taxonomic resolution needed to resolve the relationship between changing disturbance regimes and corresponding shifts in plant community composition; (3) integrate palaeoecological, archaeological and Indigenous knowledge to disentangle the complex interplay between climate, human land use, fire and vegetation structure; and (4) apply "functional palaeoecology" and the synergy between palaeoecology and genetics to understand how fire disturbance has served as a long‐standing selective agent on plants. These frameworks could increase the resolution of disturbance‐driven plant dynamics, potentially providing valuable information for future management. [ABSTRACT FROM AUTHOR]

Aim: Tropical cyclones are large‐scale disturbances that can shape the structure and dynamics of mangrove forests. Although tropical cyclone activity overlaps extensively with the latitudinal distribution of mangrove forests, the relationships between cyclone intensity and frequency and mangrove forest canopy damage and recovery are not understood at the global scale. Using remote sensing data, we examined how mangrove forest structure, climate and cyclone characteristics influence canopy cover loss and recovery dynamics. Location: Global tropics. Time period: 2000–2020. Major taxa studied: Mangrove trees. Methods: Using two satellite‐derived vegetation indices (the enhanced vegetation index and the normalized difference infrared index) from 86 cyclones affecting 56 mangrove sites across the globe, we quantified mangrove canopy loss in relationship to cyclones. Using linear regression and variance decomposition, we identified and ranked significant predictors of cyclone‐induced canopy loss and recovery. Results: Three‐quarters of the studied cyclone disturbances resulted in canopy damage. Stands exposed to high wind speeds and those close to the cyclone paths were more severely damaged, whereas lower damage magnitudes were found in sites with greater past cyclone frequency. Canopy damage was greater in tall mangrove stands but decreased with higher aboveground biomass. The distance from the cyclone path and maximum wind speed were the most important factors, representing > 50% of the explained variation in cyclone damage. There was considerable variation in canopy damage among cyclones, but rates of recovery were similar across all mangrove sites, with the main predictor of recovery time being the degree of canopy loss. Main conclusions: Our results suggest that the resistance of mangrove canopy cover to cyclone disturbance is variably tuned to the cyclone regime and vegetation characteristics, but resilience is inherent to the magnitude of canopy damage because the rate of forest canopy recovery appears to be consistent globally. [ABSTRACT FROM AUTHOR]

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Aims: Spruce beetles (Dendroctonus rufipennis) are causing widespread spruce (Picea spp.) mortality in subalpine forests in western North America. Spruce beetles are changing forest structure and composition by killing a dominant overstory species, but we know little about how the understory community responds to the increase in resource availability brought about by spruce mortality, what mechanisms drive its response, or how its response affects other forest properties and processes. Location: Glacier Lakes Ecosystem Experiments Site, Medicine Bow Mountains, Wyoming, USA. Methods: We measured understory community cover and richness in 75 permanent plots during and 10 years after an epidemic spruce beetle outbreak, and measured trait values for 46 common understory species. We used linear regression to determine how the understory community has changed over time and along a gradient of spruce mortality, and to evaluate the relative support for two mechanisms contributing to species responses. Results: Understory cover nearly doubled between sampling periods and increased the most where spruce mortality was most severe. Understory richness doubled and showed a weak positive trend with spruce mortality. Understory species with the largest increases in cover were the most frequent across the landscape before the disturbance, were the tallest at maturity and had the lowest leaf turgor loss points. Fir seedling density decreased over time, with decreases lessening with increases in understory cover. Changes in spruce seedling density were not predicted by changes in understory cover. Conclusions: Our findings highlight some of the diverse ways in which understory communities can be altered by spruce beetle outbreaks, and how the direction and magnitude of change can depend on the amount of spruce mortality as well as on priority effects and traits of pre-disturbance species. Our findings also highlight how understory community changes can have implications for other forest properties and processes, such as tree regeneration and forest recovery. [ABSTRACT FROM AUTHOR]

In disturbance‐adapted ecosystems, the removal of disturbance can lead to losses of diversity and sometimes irreversible changes in community composition. It is important to identify the thresholds at which these changes can occur, and to understand the reversibility of these shifts. We examined this question in a vernal pool ecosystem that evolved with low to moderate levels of grazing disturbance. In this system, it is not clear whether the negative effects of long‐term grazing exclusion are reversible through grazing reintroduction.We compared adjacent vernal pool wetlands in annual Mediterranean grasslands under three grazing management strategies: continuously grazed (100+ years), long‐term excluded (40+ years) and 2 years of reintroduced grazing. We also asked whether grazing treatments altered pool characteristics that are likely to influence plant community composition, and how these relationships changed with environmental conditions.Reintroducing grazing to vernal pools led to both increased diversity and native cover, but the effects on native cover were more immediate than on diversity. We identified several biotic and abiotic mechanisms related to this pattern, including changes to competitive dynamics that favour small statured native annuals and increases in hoofprint microdepressions that make soil moisture more available to plants.Synthesis and applications. Our results show that reintroduced grazing at moderate stocking rates can have significant effects on plant communities after just 2 years and can increase native cover more quickly than overall diversity. Our findings suggest that the negative effects of long‐term grazing exclusion in vernal pools may be reversible, but that land managers interested in restoring diversity should plan to monitor beyond the first two years of grazing reintroduction. [ABSTRACT FROM AUTHOR]

Despite the Philippines having one of the widest extents and most diverse seagrasses, there are limited reports on the contribution of seagrass vegetation health to organic carbon (OC). Comparative assessments of OC between conserved and disturbed seagrass meadows in a seascape are also lacking. Conservation programs (e.g., marine protected area [MPA]) contribute to the maintenance of ecosystem health and OC storage in seagrass. However, disturbances may negate the effects of MPAs. Disturbances are often due to coastal development pressures linked to the need for industry, food production, and human settlement. Here, we assessed and compared the aboveground biomass (AGB), belowground biomass (BGB), and OC between conserved and disturbed seagrass meadows, then, tested its correlation with vegetation and water quality variables. The study was conducted in Oyon Bay (northwest Philippines), one of the key seascape MPAs in the Philippines. The bay experienced disturbances from a coal power plant, aquaculture, and human settlements for approximately 30 years. Results showed 7× higher AGB, 11× higher BGB, and 1.7× higher OC in conserved sites. The low biomass and OC values in the disturbed sites were correlated to poor vegetation and water quality conditions (particularly high turbidity [ρ = 0.38], high phosphates [ρ = −0.19], and low dissolved oxygen [ρ = −0.31]). Our study showed the effectiveness of MPAs in maintaining ecosystem health and OC in seagrass, but the magnitude of disturbances lessened the benefits from MPAs. Our results have implications on the over‐ or under‐estimation of carbon sequestration not just in Philippine seagrasses but also in most Southeast Asian countries facing similar coastal development pressures. [ABSTRACT FROM AUTHOR]

The short‐term response of humpback whales to boat approach and remote biopsy sampling was investigated in a breeding ground according to age‐class, sex, female reproductive status, social context, sampling system, habitat, and repeated sampling with more than 20 years of data. In a total of 2,248 observed behavioral responses to biopsy sampling, 58.7% showed no response, 40.7% were considered to be weak or moderate responses, and only 0.5% were considered to be strong. No significant difference was found between the response of calves (young‐of‐the‐year) and that of adults, whereas juveniles responded significantly more strenuously. The response of adult whales was influenced by sex, female reproductive status, and social context. Mothers showed the most frequent response to the boat approach, but the weakest response to the biopsy sampling itself, whereas nonlactating females had the strongest response to biopsy sampling. Males responded less when sampled within a competitive group. Repeated sampling of individual adults resulted in decreasing intensity of responses across years. This comprehensive assessment has implications for management authorities, notably in approving research permits for sampling different age classes on breeding grounds. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim To investigate whether differences in the elevational trend in native and alien species richness were dependent on climate or human pressures. Specifically we tested whether life-form and/or alien/native status modifies the response of plant species richness to human population and temperature along: (1) a complete elevational gradient, and (2) within separate elevational bands that, by keeping temperature within a narrow range, elucidate the effects of human pressures more clearly. Location Two provinces ( c. 7507 km2) on the southern border of the European Alps (Italy), subdivided into 240 contiguous sampling cells ( c. 35.7 km2). Methods We used an extensive dataset on alien and native species richness across an elevation gradient (20-2900 m a.s.l.). Richness of natives and naturalized aliens were separately related to temperature, human population and Raunkiaer life-form using general linear mixed models. Life-form describes different plant strategies for survival during seasons with adverse cold/arid conditions. Results The relationship between species richness and temperature for natives was strongly dependent on life-form, while aliens showed a consistent positive trend. Similar trends across alien and native life-forms were found for the relationship between species richness and human population along the whole gradient and within separate elevational bands. Main conclusions The absence of life-form-dependent responses amongst aliens supports the hypothesis that the distribution of alien plant species richness was more related to propagule pressure and availability of novel niches created by human activities than to climatic filtering. While climate change will potentially contribute to relaxing species thermal constraints, the response of alien species to future warming will also be contingent on changes in anthropogenic pressures. [ABSTRACT FROM AUTHOR]