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Mangroves are implemented as nature‐based solutions (NbS) for coastal protection, climate change mitigation (carbon sequestration) and other services. They play a core role in providing benefits for biodiversity, livelihoods and human well‐being. Ecological research has informed the use of mangroves as NbS, but failure of NbS projects has often been due to misconceptions about mangrove ecology and the limited use of the wide range of ecological knowledge available. Enhanced knowledge of the spatial and temporal variation in ecological processes, and differentiation among mangrove tree species and assemblages (including fauna and microbial communities) in the provision of ecosystem functions and services, will support successful use of mangroves as NbS. Knowledge of mangrove responses to the interacting pressures of climate change and human uses of the coastal zone will support resilient NbS projects. Synthesis. The success of mangroves as NbS can be improved with increased incorporation of knowledge of the ecology of mangrove plants, animals and microbes and by sharing and co‐producing knowledge within mangrove societies. [ABSTRACT FROM AUTHOR]

Biodiversity loss may result in the decline in important ecosystem processes. The effect of biodiversity loss on ecosystem functioning is determined by the functional contribution of the species lost and the compensatory responses of the remaining species. It is unknown to what extent the strength of the compensatory response of the remaining species depends on resources availability. Here we evaluate how the primary production of an assemblage of salt marsh plants responds to a realistic sequence of species loss in an 7‐year experiment, with and without the addition of fertiliser. We found near‐full compensation of progressive species loss in gross community primary production by the extinction‐resistant species with fertiliser as long as one species (Triglochin maritima) remained. Without fertiliser, at least four species, including the particularly abundant species Plantago maritima, were needed to maintain gross community primary production. These results suggest that the magnitude of the compensation by extirpation‐resistant species for the decline in ecosystem processes associated with progressive biodiversity loss depends on the resource context, and that compensation after the loss of plant species can be accelerated by increasing resource availability. Ultimately, full compensation appears to be limited by the presence and abundance of species in the remaining community that possess traits that allow them to compensate for the species lost. Synthesis and applications: These findings suggests that the conclusions of a large body of biodiversity‐ecosystem experiments cannot be used for informing the management of natural systems because they do not simulate realistic extinction sequences and therefore cannot quantify the potential for compensation of ecosystem services in the real world. [ABSTRACT FROM AUTHOR]

A growing number of studies have demonstrated that biodiversity is a strong and positive predictor of ecosystem temporal stability by simultaneously affecting multiple underlying mechanisms of stability, that is dominance, asynchrony and averaging effects. However, to date, no study has disentangled the relative role of these key mechanisms of stability in biodiversity experiments.We created a species richness gradient by mimicking a loss of rare species and assessed the role of species richness on community stability and, more importantly, quantified the relative role of three stabilizing mechanisms, that is dominance (stabilization due to stable dominants compared to the rest of the species in the community), asynchrony (stabilization due to temporal asynchrony between species), and averaging effects (pure effect of diversity) on community stability across a species richness gradient.We found that extreme species loss negatively impacted community stability, but just three species were enough to stabilize biomass production to a level similar to highly diverse communities. However, the similar stability of communities resulted from differing contributions from each stabilizing mechanism, depending on the community diversity. Since less abundant species were more temporally variable, species loss stabilized the populations of the remaining species. The loss of rare and subordinate species reduced the dominance and averaging effects, but increased the asynchrony effect. Hence, the asynchrony effect played a major role in the stability of species poor communities, while the averaging effect drove most of the stability of species rich communities. Overall, dominance played only a minor role, accounting for 5%–15% of the stabilization, while asynchrony and averaging effects were dominating forces contributing to ~85%–95% of the total stabilization.Synthesis. This study highlights the importance of biodiversity and roles of dominant and rare species for long‐term community stability and, for the first time, disentangles relative roles of dominance effect, asynchrony and averaging effect on community stability in a real‐world biodiversity experiment. [ABSTRACT FROM AUTHOR]

Nature‐based solutions (NbS) involve interventions that modify ecosystems to enhance multiple ecosystem services (ES). Yet, despite our increasing knowledge of the key role that functional traits play in determining ES, certain types of NbS often do not consider a functional trait perspective. A reason for this lack of translation may be the range of NbS approaches and levels of knowledge of trait–ES relationships. Functional traits may be most useful as targets for NbS design when knowledge on trait–ES mapping is established and the NbS involves a medium or high level of management intervention. A richer understanding of causality in trait–ES and trait–resilience linkages, and context dependency in those linkages, is needed to broaden the application of functional traits in NbS. An improved understanding of trait linkages with cultural ES and how traits interact with stakeholder values to shape NbS uptake would also improve application. Synthesis: A greater consideration of functional traits will increase the efficacy of NbS projects, and could be accelerated by tackling gaps in knowledge about functional traits. Here, we envision a research agenda that both advances NbS design and leverages the varied objectives of NbS to robustly test our knowledge about functional traits. [ABSTRACT FROM AUTHOR]

Many nature‐based solutions (NBS), including urban greenspaces, urban agriculture and agroforestry, depend upon animal‐pollinated plants to sequester carbon or to provide other ecosystem services. Thus, long‐term success of these solutions also depends upon resilient pollinator communities. Despite their importance to functioning communities, a literature search revealed that 0%–3% of papers on NBS and related topics considered pollinators or pollination. Pollinators were more likely to be considered in the subgroup of papers on NBS related to agricultural production, where 12.5% considered pollination. Conservation of species interactions is essential to conservation of biodiversity and the sustained benefits of NBS. By applying our understanding of the ecology of plant‐pollinator mutualisms to the implementation of NBS, we can promote their functioning under future climatic conditions. In particular, we point to the need to identify keystone plants and pollinators, those species that contribute most to biodiversity maintenance, community stability and ecosystem function, and to leverage these species and their interactions in NBS and conservation efforts. We further advocate for the use of phylogenetic trait‐based analyses to understand the characteristics associated with keystoneness. Synthesis: Resilience of pollination services rests upon the responses of keystone species and their partners, and the likelihood that they continue to express traits that confer mutual benefit under future climates. By understanding the traits of species of outsized importance to their communities, we gain insight into the mechanisms underlying the resilience of pollination services and the NBS that rely on those services in a changing world. [ABSTRACT FROM AUTHOR]

Dead trees are vital structural elements in forests playing key roles in the carbon and nutrient cycle. Stem traits and fungal community composition are both important drivers of stem decay, and thereby affect ecosystem functioning, but their relative importance for stem decomposition over time remains unclear.To address this issue, we used a common garden decomposition experiment in a Dutch larch forest hosting fresh logs from 13 common temperate tree species. In total, 25 fresh wood and bark traits were measured as indicators of wood accessibility for decomposers, nutritional quality and chemical or physical defence mechanisms. After 1 and 4 years of decay, we assessed the richness and composition of wood‐inhabiting fungi using amplicon sequencing and determined the proportional wood density loss.Average proportional wood density loss for the first year was 18.5%, with further decomposition occurring at a rate of 4.3% year−1 for the subsequent 3 years across tree species. Proportional wood density loss varied widely across tree species in the first year (8.7–24.8% year−1) and subsequent years (0–11.3% year−1). The variation was directly driven by initial wood traits during the first decay year, then later directly driven by bark traits and fungal community composition. Moreover, bark traits affected the composition of wood‐inhabiting fungi and thereby indirectly affected decomposition rates. Specifically, traits promoting resource acquisition of the living tree, such as wide conduits that increase accessibility and high nutrient concentration, increased initial wood decomposition rates. Fungal community composition, but not fungal richness explained differences in wood decomposition after 4 years of exposure in the field, where fungal communities dominated by brown‐rot and white‐rot Basidiomycetes were linked to higher wood decomposition rate.Synthesis: Understanding what drives deadwood decomposition through time is important to understand the dynamics of carbon stocks. Here, using a tailor‐made experimental design in a temperate forest setting, we have shown that stem trait variation is key to understanding the roles of these drivers; initially, wood traits explained decomposition rates while subsequently, bark traits and fungal decomposer composition drove decomposition rates. These findings inform forest management with a view to selecting tree species to promote carbon storage. [ABSTRACT FROM AUTHOR]

How biodiversity underpins ecosystem resistance (i.e. ability to withstand environmental perturbations) and recovery (i.e. ability to return to a pre‐perturbation state), and thus, stability under extreme climatic events is a timely question in ecology. To date, most studies have focussed on the role of taxonomic diversity, neglecting how community functional composition and diversity beget stability under exceptional climatic conditions. In addition, land use potentially modulates how biodiversity and ecosystem functions respond to extreme climatic conditions.Using an 11‐year time‐series of plant biomass from 150 permanent grassland plots spanning a gradient of land‐use intensity, we examined how taxonomic and functional components of biodiversity affected resistance and recovery of biomass under extreme drought.The association between biodiversity, land use and biomass varied across years, especially in the driest years. Species‐rich or functionally diverse communities (associated with low land‐use intensity) buffered extreme droughts better, while species‐poor communities or those dominated by fast‐growing species (associated with high land‐use intensity) had higher recovery capabilities after a moderate‐to‐extreme drought.Synthesis. Our results show that plant community functional and taxonomic components determine grasslands resistance and recovery under moderate‐to‐extreme drought. In turn, this points to the importance of designing landscapes with both extensively and intensively managed grasslands. Functionally or taxonomically rich communities (favoured under low land‐use intensity) would preserve biomass under extreme droughts, whereas species‐poor or fast‐growing communities (favoured by high land‐use intensity) would restore biomass after extreme droughts. [ABSTRACT FROM AUTHOR]

Productive grasslands in temperate regions have relied strongly on low plant diversity with high management intensity and fertiliser inputs. Increasing plant diversity can provide high yields of digestible forage for livestock production with lower environmental impacts, and thus represents a diversity‐dependent nature‐based solution that can deliver multiple ecosystem functions. Sharing lessons from the design of managed, productive grassland communities, we address the following questions: how can we identify combinations of plant species that best deliver a selected function or multiple functions? and; when is community composition more important than species richness? We describe approaches that separate plant diversity into its underlying components: species richness, composition and relative abundance. Disentangling these three components facilitates a more nuanced understanding of how diversity can contribute to the design of diversity‐dependent nature‐based solutions. [ABSTRACT FROM AUTHOR]

1. Biodiversity is an important component of natural ecosystems, with higher species richness often correlating with an increase in ecosystem productivity. Yet, this relationship varies substantially across environments, typically becoming less pronounced at high levels of species richness. However, species richness alone cannot reflect all important properties of a community, including community evenness, which may mediate the relationship between biodiversity and productivity. If the evenness of a community correlates negatively with richness across forests globally, then a greater number of species may not always increase overall diversity and productivity of the system. Theoretical work and local empirical studies have shown that the effect of evenness on ecosystem functioning may be especially strong at high richness levels, yet the consistency of this remains untested at a global scale. 2. Here, we used a dataset of forests from across the globe, which includes composition, biomass accumulation and net primary productivity, to explore whether productivity correlates with community evenness and richness in a way that evenness appears to buffer the effect of richness. Specifically, we evaluated whether low levels of evenness in speciose communities correlate with the attenuation of the richness–productivity relationship. 3. We found that tree species richness and evenness are negatively correlated across forests globally, with highly speciose forests typically comprising a few dominant and many rare species. Furthermore, we found that the correlation between diversity and productivity changes with evenness: at low richness, uneven communities are more productive, while at high richness, even communities are more productive. 4. Synthesis. Collectively, these results demonstrate that evenness is an integral component of the relationship between biodiversity and productivity, and that the attenuating effect of richness on forest productivity might be partly explained by low evenness in speciose communities. Productivity generally increases with species richness, until reduced evenness limits the overall increases in community diversity. Our research suggests that evenness is a fundamental component of biodiversity–ecosystem function relationships, and is of critical importance for guiding conservation and sustainable ecosystem management decisions.

Variation in decay rates across woody species is a key uncertainty in predicting the fate of carbon stored in deadwood, especially in the tropics. Quantifying the relative contributions of biotic decay agents, particularly microbes and termites, under different climates and across species with diverse wood traits could help explain this variation. To fill this knowledge gap, we deployed woody stems from 16 plant species native to either rainforest (n = 10) or savanna (n = 6) in northeast Australia, with and without termite access. For comparison, we also deployed standardized, non-native pine blocks at both sites. We hypothesized that termites would increase rates of deadwood decay under conditions that limit microbial activity. Specifically, termite contributions to wood decay should be greater under dry conditions and in wood species with traits that constrain microbial decomposers. Termite discovery of stems was surprisingly low with only 17.6% and 22.6% of accessible native stems discovered in the rainforest and savanna respectively. Contrary to our hypothesis, stems discovered by termites decomposed faster only in the rainforest. Termites discovered and decayed pine blocks at higher rates than native stems in both the rainforest and savanna. We found significant variation in termite discovery and microbial decay rates across native wood species within the same site. Although wood traits explained 85% of the variation in microbial decay, they did not explain termite-driven decay. For stems undiscovered by termites, decay rates were greater in species with higher wood nutrient concentrations and syringyl:guiacyl lignin ratios but lower carbon concentrations and wood densities. Synthesis. Ecosystem-scale predictions of deadwood turnover and carbon storage should account for the impact of wood traits on decomposer communities. In tropical Australia, termite-driven decay was lower than expected for native wood on the ground. Even if termites are present, they may not always increase decomposition rates of fallen native wood in tropical forests. Our study shows how the drivers of wood decay differ between Australian tropical rainforest and savanna; further research should test whether such differences apply world-wide.

Vegetation structural complexity (VSC)—the three‐dimensional distribution of plants within an ecosystem—is an important ecological trait. To date, research has focused primarily on the effects of VSC on ecological patterns and processes, but comparatively little is known about what drives variation in VSC.Recent advances in active remote sensing technology, particularly light detection and ranging and radio detection and ranging, have allowed the measurement of VSC at unprecedented spatial scales and resolutions. Out of this and earlier work has emerged evidence that VSC is typically associated with greater ecosystem functioning (especially microclimate regulation, productivity, faunal diversity and habitat provisioning), making restoration of vegetation complexity a potentially powerful restoration tool.Recent studies of VSC across natural and experimental gradients of plant diversity have also revealed that more diverse plant communities tend to be more structurally complex. However, the shape and generality of this relationship—and the mechanism(s) by which phytodiversity might contribute to structural complexity—remain poorly understood.Here, we review how active remote sensing has facilitated recent VSC research and shaped our understanding of the relationship between vegetation complexity and ecosystem function. We then present a theoretical framework for the relationship between phytodiversity and VSC based on classic biodiversity‐ecosystem functioning principles. Finally, we evaluate the evidence for the notion that diverse plant assemblages tend to be more structurally complex and explore the shape of the relationship between phytodiversity and VSC using data from 13 recent remote sensing studies.Synthesis. The relationship between phytodiversity and VSC appears to be almost universally positive. Preliminary evidence further suggests that the most common relationships between phytodiversity and VSC are linear or saturating, indicating that the extent of functional redundancy between species varies across plant communities and ecosystems. In contrast, we find little evidence for exponential or negative relationships between plant diversity and VSC, suggesting that even modest increases in plant diversity could markedly increase structural complexity. Additional investigations of phytodiversity‐VSC relationships are necessary to establish whether the observed positive relationships are causal (and, if so, in which direction) and to clarify the potential impact of plant community restoration on structural complexity and broader ecosystem function. [ABSTRACT FROM AUTHOR]

1. Revealing the ecological consequences of bark multifunctionality and its underlying traits has become a relatively new but essential focus in plant ecology. Although the enormous differences between the most crucial bark layers, that is, inner and outer bark, in structure and functions have been widely recognized, the overall bark has been regarded as a homogenous tissue in most bark-related studies. This has led to poor knowledge on the functional independence, specialized contributions and possible linkages of inner and outer bark traits across tree species when further evaluating the crucial ecosystem functions that bark provides, especially in driving variation in bark decomposition. 2. To fill this research gap, we used a ‘common garden experiment’ on deadwood of six gymnosperms in a temperate forest in the Netherlands over 4 years of decomposition. We evaluated the differences and associations between the inner and outer bark in initial functional traits, decomposition rates and afterlife effects of traits in driving in situ bark decomposition across tree species at the earlier decomposition stage. 3. We report four main findings: (1) inner and outer bark traits varied significantly and were not coordinated across tree species; (2) correspondingly, the decomposition of the inner and outer bark were asynchronous and not coordinated across species and inner bark generally decomposed faster than outer bark; (3) the strong predictive traits driving bark decomposability were bark layer-specific, with several inner bark traits controlling inner bark decomposition rates but outer bark decomposability being poorly predicted by outer bark traits and (4) besides being controlled by inner bark traits, inner bark decomposition was also indirectly regulated by several functional traits and the structure-related trait spectrum of outer bark. 4. Synthesis. This is the first study that has linked functional traits, decomposability and afterlife effects of the inner and outer bark within the bark quantitatively. We highlight the significance of separating functional traits and ecological consequences of the inner and outer bark in research in bark ecology and deadwood dynamics, rather than erroneously considering bark as a homogeneous tissue. Such research will help to better evaluate the function-oriented contribution of bark to the turnover of forest carbon and biogeochemical cycles from local to global scale. [ABSTRACT FROM AUTHOR]

Litter decomposition is controlled by climate, litter quality and decomposer communities. Because the decomposition of specific litter types is also influenced by the properties of adjacent types, mixing litter types may result in non‐additive effects on overall decomposition rates. The strength of these effects seems to depend on the litter functional diversity. However, it is unclear which functional traits or combination of traits explain litter mixture effects and whether these depend on the range of trait values and the ecosystems involved. These uncertainties hamper our ability to predict decomposition in plant communities.We aimed at understanding whether and how functional diversity (measured as functional dispersion, FDis) influences litter decomposition, and how this influence varies among different climates and across decomposition stages. We calculated FDis based on litter traits related to nutrient concentrations or to litter recalcitrance, and tested whether these diversity measures and climatic parameters (soil moisture and temperature) explained litter mixture effects on decomposition.Additive mixture effects (i.e. decomposition of mixtures equalling the mean decomposition of the single litter types) were common in most of the evaluated climates. Non‐additive, negative effects were mainly restricted to the driest and warmest sites, and decreased with time. Non‐additive effects increased in magnitude with the mixtures' FDis, with positive effects being related to FDis in nutrient traits and negative effects being related to FDis in recalcitrance traits.Synthesis. Litter mixing did not have strong effects on decomposition rates across the studied climatic gradient overall, and the direction and intensity of the mixture effects were context dependent. The effects were stronger and more negative in the dryer ecosystems. Where effects were found, functional diversity calculated from selected groups of traits (related to nutrients or litter recalcitrance) predicted mixture effects, especially where trait ranges were broad, though much of the variation remains unexplained. We propose that functional diversity metrics based on litter traits that are mechanistically relevant, applied to diverse site‐specific litter mixtures in different climates, can help to better understand under which conditions and in which direction litter diversity affects decomposition. [ABSTRACT FROM AUTHOR]

One metric of peatland restoration success is the re‐establishment of a carbon sink, yet considerable uncertainty remains around the time‐scale of carbon sink trajectories. Conditions post‐restoration may promote the establishment of vascular plants such as graminoids, often at greater density than would be found in undisturbed peatlands, with consequences for carbon storage. Although graminoid species are often considered as a single plant functional type (PFT) in land‐atmosphere models, our understanding of functional variation among graminoid species is limited, particularly in a restoration context.We used a traits‐based approach to evaluate graminoid functional variation and to assess whether different graminoid species should be considered a single PFT or multiple types. We tested hypotheses that greenhouse gas fluxes (CO2, CH4) would vary due to differences in plant traits among five graminoid species in a restored peatland in central Alberta, Canada. We further hypothesized that species would form two functionally distinct groupings based on taxonomy (grass, sedge).Differences in gas fluxes among species primarily reflected variation in leaf physiology related to photosynthetic efficiency and resource‐use, and secondarily by plant size. Multivariate analyses did not reveal distinct functional groupings based on taxonomy or environmental preferences. Rather, we identified functional groups defined by plant traits and carbon fluxes that are consistent with ecological strategies related to differences in growth rate, resource‐acquisition and leaf economics, representing plants with either a strategy to grow quickly and invest in resource capture or to prioritize structural investment and resource conservation. These functional groups displayed larger average carbon fluxes compared to graminoid PFTs currently used in modelling.Synthesis. Existing PFT designations in peatland models may be more appropriate for pristine or high‐latitude systems than those under restoration. Although replacing PFTs with plant traits remains a challenge in peatlands, traits related to leaf physiology and growth rate strategies offer a promising avenue for future applications. [ABSTRACT FROM AUTHOR]

Biodiversity in urban ecosystems has the potential to increase ecosystem functions and support a suite of services valued by society, including services provided by soils. Specifically, the sequestration of carbon in soils has often been advocated as a solution to mitigate the steady increase in CO2 concentration in the atmosphere as a key driver of climate change. However, urban ecosystems are also characterized by an often high level of ecological novelty due to profound human‐mediated changes, such as the presence of high numbers of non‐native species, impervious surfaces or other disturbances. Yet it is poorly understood whether and how biodiversity affects ecosystem functioning and services of urban soils under these novel conditions.In this study, we assessed the influence of above‐ and below‐ground diversity, as well as urbanization and plant invasions, on multifunctionality and organic carbon stocks of soils in non‐manipulated grasslands along an urbanization gradient in Berlin, Germany. We focused on plant diversity (measured as species richness and functional trait diversity) and, in addition, on soil organism diversity as a potential mediator for the relationship of plant species diversity and ecosystem functioning.Our results showed positive effects of plant diversity on soil multifunctionality and soil organic carbon stocks along the entire gradient. Structural equation models revealed that plant diversity enhanced soil multifunctionality and soil organic carbon by increasing the diversity of below‐ground organisms. These positive effects of plant diversity on soil multifunctionality and soil fauna were not restricted to native plant species only, but were also exerted by non‐native species, although to a lesser degree.Synthesis. We conclude that enhancing diversity in plants and soil fauna of urban grasslands can increase the multifunctionality of urban soils and also add to their often underestimated but very valuable role in mitigating effects of climate change. [ABSTRACT FROM AUTHOR]

Abstract For decades, ecologists have investigated the effects of tree species diversity on tree productivity at different scales and with different approaches ranging from observational to experimental study designs. Using data from five European national forest inventories (16,773 plots), six tree species diversity experiments (584 plots), and six networks of comparative plots (169 plots), we tested whether tree species growth responses to species mixing are consistent and therefore transferrable between those different research approaches. Our results confirm the general positive effect of tree species mixing on species growth (16% on average) but we found no consistency in species‐specific responses to mixing between any of the three approaches, even after restricting comparisons to only those plots that shared similar mixtures compositions and forest types. These findings highlight the necessity to consider results from different research approaches when selecting species mixtures that should maximize positive forest biodiversity and functioning relationships.

Biodiversity describes the variety of life and may influence properties and processes of ecosystems, such as biomass production and resistance to disturbance. We investigated the effects of multiple facets of biodiversity – species richness and composition of the community, and intraspecific diversity in two key species – on both production and resistance of experimentally‐assembled biological soil crusts (biocrusts). We found that productivity was most strongly influenced by community composition (variation in the presence and relative proportions of community members), and weakly positively influenced by species richness. Intraspecific diversity, encompassing both the richness and composition of clones, had a neutral effect on community productivity within one focal species (Syntrichia caninervis), but a moderately negative effect on productivity within the other focal species (S. ruralis). Resistance was also most strongly influenced by community composition, although different sets of species contributed most to resistance and production. Resistance was not affected by either species richness or intraspecific diversity in either focal species. Our findings supported our general expectation that community‐level facets of biodiversity would be more influential than intraspecific diversity within a species because trait variability among species is usually greater than that within. These results also indicated that although species richness is often thought to strongly affect both productivity and resistance, the presence, absence and relative abundance of particular species may be more influential to both. Simultaneous manipulation of multiple facets of biodiversity in experiments may lead to a more complete understanding of the variety of ways in which biodiversity may regulate ecological systems. [ABSTRACT FROM AUTHOR]

Ecosystem stability is essential to its sustainable functions and services to humanity. Although climate warming is projected to vary from 1 to 5°C by the end of 21st century, how the temporal stability of plant community biomass production responds to different warming scenarios remains unclear.To fill this knowledge gap, we conducted a 6‐year field experiment with three levels of warming treatments (control, +1.5°C, +2.5°C) by using infrared radiators, in an alpine meadow on the Qinghai–Tibet Plateau.We found that low‐level warming (+1.5°C), compared to the control, did not significantly change the temporal stability of plant community biomass production and its underlying causes, including species diversity, compensatory dynamics, mean–variance scaling, biomass temporal stability of plant population (the average of temporal stability of species biomass production of all species in the community) or dominant species. However, high‐level warming (+2.5°C) significantly reduced them. Species diversity was not a significant predictor of temporal stability of plant community biomass production in this species‐rich ecosystem, regardless of the magnitude of warming, while co‐existing species compensatory dynamics and the biomass temporal stability of dominant species determined the response of temporal stability of plant community biomass production to warming.Synthesis. Our results suggest that the responses of plant community biomass temporal stability and its underlying mechanisms to climate warming depend on warming magnitudes. The findings highlight the various responses of ecosystem functions and services to different warming scenarios and imply that ecosystem will fail to maintain and provide stable biomass‐related services for humanity under high‐level climate warming. [ABSTRACT FROM AUTHOR]

Forests can contribute to climate change mitigation by sequestering carbon when management intensity is reduced. However, there is high uncertainty regarding biomass dynamics in temperate forests after the cessation of management. We used forest inventory data from an extensive network of 224 plots in 37 natural forest reserves (NFR) covering a wide environmental gradient with mean annual temperatures ranging from 1 to 10.4 °C and mean annual precipitation ranging from 901 to 2317 mm. Inventories had been conducted approximately every 10 years during the last 60 years. We used mixed effect models to (i) analyse biomass development, (ii) assess the role of time since the cessation of management (TSCM) and (iii) disentangle the environmental and forest structural drivers of biomass change. After the cessation of management and in the absence of high-severity natural disturbances, biomass accumulated gradually along a saturation curve. There were large differences in biomass among reserves and plots, with values ranging from 101 Mg ha−1 to 851.2 Mg ha−1, with a median of 362.1 Mg ha−1 (SD = 122.5 Mg ha−1). The biomass curve did not yet tend towards an equilibrium, most likely because the majority of the NFRs do not exceed 100 years of TSCM. Compared to higher elevations, forests at lower, warmer sites showed a larger total biomass and higher rates of biomass accumulation. We found a reduction by 148 Mg ha−1 of biomass per 1000 m of elevation gain. The strongest positive rate of change (>8 Mg ha−1 year−1) was found in forests with high basal area (>60 m2 ha−1) and medium to high levels of tree density (1500 to 2000 stems ha−1). Overall, most reserves have not reached a biomass equilibrium yet and continue to act as carbon sinks in tree biomass. This highlights the carbon sequestration capacity of forest reserves and their role as carbon pools. [Display omitted] • Long-term forest inventories of unmanaged forest used to understand biomass dynamics. • Forests after cessation of management increase their biomass over long time periods. • In the absence of natural disturbances biomass asymptotically approaches saturation. • Large differences in biomass among plots, ranging from 101 Mg ha−1 to 851.2 Mg ha−1. • The studied unmanaged forests continue to act as carbon sinks in tree biomass. [ABSTRACT FROM AUTHOR]

Climate and litter quality drive litter decomposition, but there is currently little consensus on their relative importance, likely because studies differ in the duration, the climatic gradients and variability in litter‐trait values. Understanding these drivers is important because they determine the direct and indirect (via vegetation composition) effects of climate change on decomposition and thereby on carbon and nutrient cycling.We studied how microclimate (soil moisture and temperature) and litter traits interactively affect litter mass loss, by using a reciprocal litter translocation experiment along a large climatic gradient in Chile. We followed decomposition for 2 years and used 30 plant species with a wide spectrum of functional‐trait values.Litter traits had a strong impact on litter decomposition across the gradient, while an increase in decomposition with soil moisture was observed only in the wettest climates. Overall, soil moisture increased considerably in importance, relative to trait effects, at later decomposition stages, from c. 15% of the importance of traits after 3 and 6 months to c. 110% after 24 months. Moreover, analysing subsets of the 30 species showed that trait effects on litter decomposition gained in importance when including a greater variation in trait values.Synthesis. The relative effects of litter traits and climate on decomposition depend on the ranges in climate and litter traits considered and change with time. Our study emphasizes the critical role of representative ranges in climate and functional trait values for understanding the drivers of litter decomposition and for improving predictions of climate‐change effects on this important ecosystem process. [ABSTRACT FROM AUTHOR]

Climate change will increase the likelihood and severity of droughts into the future. Although diversity may buffer plant communities against the negative effects of drought, the mechanisms underlying this pattern remain unclear. Higher‐diversity plant communities may have a higher likelihood of including more drought‐resistant species that can compensate for drought‐sensitive species ("insurance effects"). Alternatively, higher‐diversity communities may alter environmental conditions and improve performance of even drought‐sensitive species. Here we planted nonleguminous forbs and grasses into monocultures and four‐ and eight‐species mixtures, and measured species and plot productivity every year from 2000 to 2010. We found that six of our eight species were suppressed when growing in monoculture during dry years. These same species were unaffected by drought when growing in higher‐diversity mixtures. Because of this poor performance in monoculture (not insurance effects), the biodiversity productivity relationship was strongest during the driest years. If biodiversity ameliorates hot/dry conditions and therefore improves performance of drought‐sensitive species during periods of low rainfall, this may mean biodiversity can be used as a tool to protect individual species from drought conditions. [ABSTRACT FROM AUTHOR]

Random species loss has been shown experimentally to reduce ecosystem function, sometimes more than other anthropogenic environmental changes. Yet, controversy surrounds the importance of this finding for natural systems where species loss is non‐random.We compiled data from 16 multi‐year experiments located at a single native tallgrass prairie site. These experiments included responses to 11 anthropogenic environmental changes, as well as non‐random biodiversity loss either the removal of uncommon/rare plant species or the most common (dominant) species.As predicted by the mass ratio hypothesis, loss of a dominant species had large impacts on productivity that were comparable to other anthropogenic drivers. In contrast, the loss of uncommon/rare species had small effects on productivity despite having the largest effects on species richness.The anthropogenic drivers that had the largest effects on productivity nitrogen, irrigation, and fire experienced not only loss of species but also significant changes in the abundance and identity of dominant species.Synthesis. These results suggest that mass ratio effects, rather than species loss per se, are an important determinant of ecosystem function with environmental change. [ABSTRACT FROM AUTHOR]

In tropical forests, epiphytes increase habitat complexity and provision services rare to canopy environments, such as water retention, nutrient cycling, and microclimate refuge. These services facilitate species diversity and coexistence in terrestrial ecosystems, and while their utility in forest ecosystems is appreciated for the Bromeliaceae of the Neotropics, fewer studies have examined the role of Paleotropic epiphytes in ecological niche theory. Here, we compare herpetofaunal presence, abundance, and diversity of in bird's nest fern (Asplenium nidus complex; BNF) to other microhabitats in Madagascar and the Philippines. We measure BNF fern microclimates, examine temporal use of canopy microhabitats, and test models of fern characteristics hypothesized to predict herpetofaunal use. In both countries, one in five BNFs were occupied by herpetofauna, mostly amphibians, and species using BNFs were highly dissimilar from those in other microhabitats. Herpetofaunal presence and abundance were greater in BNFs than in other canopy microhabitats and were most commonly used during the day when fern temperatures were highly buffered. Finally, BNF area was the best predictor of herpetofaunal presence and abundance, compared to canopy cover and BNF height. Importantly, these patterns remained consistent despite the distinct phylogenetic histories of our two communities (Asian versus African). Our results suggests that BNFs and their microclimate services play a critical role in the ecology of two Paleotropic forests, and facilitate the use of canopy habitats by climate-sensitive species. However, future studies are needed to assess the consistency of BNFs' utility as a microclimate refuge across their large range. [ABSTRACT FROM AUTHOR]

For decades, ecologists have investigated the effects of tree species diversity on tree productivity at different scales and with different approaches ranging from observational to experimental study designs. Using data from five European national forest inventories (16,773 plots), six tree species diversity experiments (584 plots), and six networks of comparative plots (169 plots), we tested whether tree species growth responses to species mixing are consistent and therefore transferrable between those different research approaches. Our results confirm the general positive effect of tree species mixing on species growth (16% on average) but we found no consistency in species‐specific responses to mixing between any of the three approaches, even after restricting comparisons to only those plots that shared similar mixtures compositions and forest types. These findings highlight the necessity to consider results from different research approaches when selecting species mixtures that should maximize positive forest biodiversity and functioning relationships. [ABSTRACT FROM AUTHOR]

Global change scenarios predict that precipitation regimes will become more variable in many parts of the world, extending drought periods and increasing rainfall intensity. Under these conditions, soil microbial community composition will likely change in ways that have implications for microbially-mediated nutrient cycling. Understanding these responses is key to predicting consequential changes in ecosystem functions. A 30 day incubation experiment was used to investigate the response of microbial community structure to three different soil moisture treatments, namely, constantly moist (CM), constantly dry (CD), and drying-rewetting (DRW), in soils of three different land condition types (Remnant, Restored, and Old-field) from Para Woodlands Nature Reserve, South Australia. Soil respiration and inorganic N transformations were approximately the same across soils, despite fundamental differences in physicochemical properties, vegetation communities, and land-use history. Soil microbial community structure changed in response to the different soil moisture treatments; responses of taxa was divergent among soils. These results demonstrate that changes to soil moisture regimes under climate projections will almost certainly have consequences for soil microbial communities and C and N dynamics. The results highlight the need for further research to understand the mechanisms driving divergent responses to soil moisture, particularly in areas of different land-use types. • C and N cycling, and microbial community response to soil moisture were examined. • Response of soil inorganic N pools and respiration were similar across soils. • Soil microbial community structure changed in response to moisture treatments. [ABSTRACT FROM AUTHOR]

Nitrogen (N) and phosphorus (P) often limit biological processes in terrestrial ecosystems. Based on previous studies mainly focusing on plants, the concept of resource limitation has evolved towards a theory of (co)limitations by multiple resources. However, this ecological framework has not been applied to analyse how soil micro‐organisms and plants concurrently respond to N and/or P addition, and whether these responses are constrained by phylogenetic relatedness.Here, we applied this framework to analyse microbial and plant responses at community and taxon levels to different fertilization treatments (four N levels without P; four P levels without N and four NP levels) in Tibetan grasslands.Total plant biomass showed serial limitation by N then P, and most plant species were limited by N only. Total archaeal abundance decreased with P addition, but diverse nutrient limitation types were observed for archaeal taxa. Closely related archaeal taxa tended to similarly respond to N, and functional similarity between distant archaeal groups was observed for response to P, possibly due to functional convergence. In contrast, total bacteria slightly increased with P addition only when plants remained N limited, whereas without N limitation, plants rather than bacteria benefited from P addition. Most bacterial taxa were limited by other resources than N and P, and no clear phylogenetic signals were observed regarding bacterial responses to N/P additions.Synthesis. We propose a novel approach for characterizing microbial response types to nutrient addition. It demonstrates that in Tibetan meadows, most dominant plant species, archaea and bacteria, respectively, depend on N, both N and P and other resources. [ABSTRACT FROM AUTHOR]

Ecosystem processes are driven by both environmental variables and the attributes of component species. The extent to which these effects are independent and/or dependent upon each other has remained unclear. We assess the extent to which climate affects net primary productivity (NPP) both directly and indirectly via its effect on plant size and leaf functional traits.Using species occurrences and functional trait databases for North and South America, we describe the upper limit of woody plant height within 200 × 200 km grid‐cells. In addition to maximum tree height, we quantify grid‐cell means of three leaf traits (specific leaf area, and leaf nitrogen and phosphorus concentration) also hypothesized to influence productivity. Using structural equation modelling, we test the direct and indirect effects of environment and plant traits on remotely sensed MODIS‐derived estimates of NPP, using plant size (satellite‐measured canopy height and potential maximum tree height), leaf traits, growing season length, soil nutrients, climate and disturbances as explanatory variables.Our results show that climate affects NPP directly as well as indirectly via plant size in both tropical and temperate forests. In tropical forests NPP further increases with leaf phosphorus concentration, whereas in temperate forests it increases with leaf nitrogen concentration. In boreal forests, NPP most strongly increases with increasing temperature and neither plant size nor leaf traits have a significant influence.Synthesis. Our results suggest that at large spatial scales plant size and leaf nutrient traits can improve predictions of forest productivity over those based on climate alone. However, at higher latitudes their role is overridden by stressful climate. Our results provide independent empirical evidence for where and how global vegetation models predicting carbon fluxes could benefit from including effects of plant size and leaf stoichiometry. [ABSTRACT FROM AUTHOR]

A growing body of empirical evidence has suggested that biodiversity affects the simultaneous performance of multiple ecosystem functions (i.e. ecosystem multifunctionality). Given increasing environmental variability and uncertainty under global change, an emerging question is how biodiversity influences the stability of multiple functions (i.e. multifunctional stability). We currently know little, however, about the determinants and mechanisms of multifunctional stability, which is of practical importance for ensuring the sustainable provision of multiple functions.Here, we examined mechanisms contributing to stability (quantified as the ratio of the mean to the standard deviation) of multiple functions related to ecosystem productivity and carbon sequestration, including plant above‐ground and below‐ground productivity, litter production, gross primary productivity and ecosystem respiration, in a large grassland biodiversity experiment in Inner Mongolia.We found that community‐wide species asynchrony was a strong driver to stabilize multiple functions. Community‐wide asynchrony mediated the positive effects of species richness and response diversity (describing how species with similar effects on ecosystem function respond differently to environmental change) on multifunctional stability. However, species richness had a negative direct effect on multifunctional stability because, although it increased the averaged temporal mean of multiple functions, it strongly increased the averaged temporal standard deviation of multiple functions. The overall effects of species richness on multifunctional stability were thus negative, whereas those of response diversity were positive.Synthesis. The studied ecosystem functions related to ecosystem productivity and carbon sequestration are important in natural grasslands across the world. We conclude that species asynchrony and response diversity, rather than species richness, are key to the ecosystem multifunctional stability. The loss of response diversity and compensatory mechanisms would likely reduce the long‐term sustainability of grasslands in the face of global change. [ABSTRACT FROM AUTHOR]

Tropical peatlands, which provide important functions such as biodiversity provisioning and carbon (C) storage, are currently threatened by land‐use conversions. Thus, conservation and restoration efforts are needed to maintain their functions. Conservation concepts aiming to separate human from ecosystems are no longer conceivable. Therefore, understanding peatland resilience to human disturbance, that is the ability of peatland ecosystems to maintain their structure and function despite perturbations and to return to their predisturbance states, can assist with integrating human needs into conservation strategies and improving restoration effectiveness.Understanding ecosystem resilience is often impeded by a lack of long‐term data, which can be obtained from palaeoecological studies. Located close to the archaeological remains of the Malayu Empire, the Sungai Buluh peatland in Sumatra, Indonesia provides an opportunity to study the resilience of a tropical peatland to past human disturbance. We subjected a 250‐cm‐long peat core to palynological, charcoal and C content analyses to delineate the anthropogenic impact on the peatland and the ecosystem's response.The results revealed that extensive human activities in Sungai Buluh such as logging, grazing/cut‐and‐carry, and wild‐harvesting started soon after humans occupied the vicinity of the peatland c. 1,000 cal yr bp. Even without fire use and cultivation, these activities were able to alter vegetation composition and decrease the peatland's C sequestration capacity.Following site abandonment after the demise of the Malayu Empire at c. 600 cal yr bp, the palaeoecological record suggests that the Sungai Buluh peatland recovered in terms of both floristic composition and C sink function, with the latter recovering faster (c. 60 years) than the former (c. 170 years).Synthesis. The palaeoecological record from Sungai Buluh provides the first evidence of tropical peatland recovery following human disturbance, which can help improve present peatland conservation/restoration strategies. The design of peatland wise‐use strategies can mimic the "resilience‐friendly" human activities identified in this study. Consideration should also be given to selecting rapidly regenerating taxa for cost‐and‐effort‐efficient restoration strategies. Additionally, the 170‐year recovery time of the Sungai Buluh peatland suggests that the 60‐year timeframe currently allocated in most tropical peatland restoration projects may be insufficient. The palaeoecological record from Sungai Buluh provides the first evidence of tropical peatland recovery following human disturbance, which can help improve present peatland conservation/restoration strategies. The design of peatland wise‐use strategies can mimic the "resilience‐friendly" human activities identified in this study. Consideration should also be given to selecting rapidly regenerating taxa for cost‐and‐effort‐efficient restoration strategies. Additionally, the 170‐year recovery time of the Sungai Buluh peatland suggests that the 60‐year timeframe currently allocated in most tropical peatland restoration projects may be insufficient. [ABSTRACT FROM AUTHOR]

Consumer communities play an important role in maintaining ecosystem structure and function. In seagrass systems, algal regulation by mesograzers provides a critical maintenance function which promotes seagrass productivity. Consumer communities also represent a key link in trophic energy transfer and buffer negative effects to seagrasses associated with eutrophication. Such interactions are well documented in the literature regarding temperate systems, however, it is not clear if the same relationships exist in tropical systems. This study aimed to identify if the invertebrate communities within a tropical, multispecies seagrass meadow moderated epiphyte abundance under natural conditions by comparing algal abundance across two sites at Green Island, Australia. At each site, paired plots were established where invertebrate assemblages were perturbed via insecticide manipulation and compared to unmanipulated plots. An 89% increase in epiphyte abundance was seen after six weeks of experimental invertebrate reductions within the system. Using generalised linear mixed-effect models and path analysis, we found that the abundance of invertebrates was negatively correlated with epiphyte load on seagrass leaves. Habitat species richness was seen to be positively correlated with invertebrate abundance. These findings mirrored those of temperate systems, suggesting this mechanism operates similarly across latitudinal gradients.

Abstract: In grasslands and savannas, fire regime—frequently a major determinant of woody encroachment, herbaceous species composition and diversity, and nutrient cycling—is influenced by the quantity and characteristics of plant fuel. Laboratory studies reveal variation in flammability among herbaceous species, but field experiments are needed to assess whether herbaceous species composition meaningfully affects ecosystem‐scale fire behaviour. In our North American tallgrass prairie study system, grasses’ thinner leaves and longer leaf retention appeared to create a finer, more aerated, more connected fuel bed than forbs. We tested the hypothesis that grasses promote fire spread area, fire intensity, and associated facets of fire behaviour more strongly than an equivalent mass of forbs. We characterized spring fires over multiple years in 315 annually ignited plots spanning profound gradients of plant biomass, cover, and grass:forb ratio that resulted from species richness and composition treatments, in a 20‐year grassland biodiversity experiment. Grasses increased fire spread and associated facets of fire behaviour, compared with an equivalent biomass or cover of forbs. Grass dominance increased fire spread area—or equivalently increased fire frequency at any given point. For fire to spread through 50% of the 9 m × 9 m plot area required approximately twice as high an abundance of forbs as of grasses. Grass dominance also resulted in fires that advanced faster, were more intense (higher rates of heat release per unit fireline length), caused more damage to plants, and released heat to greater heights. Fire temperature at 50 cm above‐ground was about twice as high in plots with only grasses as in plots with the same biomass of forbs. Synthesis. Even within herbaceous ecosystems that may appear homogenously flammable compared with less flammable woody ecosystems, fuel quality—specifically, the proportional abundance of grasses—combines with fuel quantity and ignitions to determine effective fire regime at a given point. In spring burns, grass‐dominated plots burn more completely and generate higher temperatures, and thus better suppress woody plants and volatilize more nutrients, than forb‐dominated plots (holding all else equal). [ABSTRACT FROM AUTHOR]

Abstract: A positive relationship between biodiversity and ecosystem stability has been reported in many ecosystems; however, it has yet to be determined whether and how spatial scale affects this relationship. Here, for the first time, we assessed the effects of alpha, beta and gamma diversity on ecosystem stability and the scale dependence of the slope of the diversity–stability relationship. By employing a long‐term (33 years) dataset from a temperate grassland, northern China, we calculated the all possible spatial scales with the complete combination from the basic 1‐m2 plots. Species richness was positively associated with ecosystem stability through species asynchrony and overyielding at all spatial scales (1, 2, 3, 4 and 5 m2). Both alpha and beta diversity were positively associated with gamma stability. Moreover, the slope of the diversity–area relationship was significantly higher than that of the stability–area relationship, resulting in a decline of the slope of the diversity–stability relationship with increasing area. Synthesis. With the positive species diversity effect on ecosystem stability from small to large spatial scales, our findings demonstrate the need to maintain a high biodiversity and biotic heterogeneity as insurance against the risks incurred by ecosystems in the face of global environmental changes. [ABSTRACT FROM AUTHOR]

Abstract: Ecosystems vary widely in their responses to biodiversity change, with some losing function dramatically while others are highly resilient. However, generalizations about how species‐ and community‐level properties determine these divergent ecosystem responses have been elusive because potential sources of variation (e.g., trophic structure, compensation, functional trait diversity) are rarely evaluated in conjunction. Ecosystem vulnerability, or the likely change in ecosystem function following biodiversity change, is influenced by two types of species traits: response traits that determine species’ individual sensitivities to environmental change, and effect traits that determine a species’ contribution to ecosystem function. Here we extend the response‐effect trait framework to quantify ecosystem vulnerability and show how trophic structure, within‐trait variance, and among‐trait covariance affect ecosystem vulnerability by linking extinction order and functional compensation. Using in silico trait‐based simulations we found that ecosystem vulnerability increased when response and effect traits positively covaried, but this increase was attenuated by decreasing trait variance. Contrary to expectations, in these communities, both functional diversity and trophic structure increased ecosystem vulnerability. In contrast, ecosystem functions were resilient when response and effect traits covaried negatively, and variance had a positive effect on resiliency. Our results suggest that although biodiversity loss is often associated with decreases in ecosystem functions, such effects are conditional on trophic structure, and the variation within and covariation among response and effect traits. Taken together, these three factors can predict when ecosystems are poised to lose or gain function with ongoing biodiversity change. [ABSTRACT FROM AUTHOR]

Experiments have shown positive biodiversity-ecosystem functioning (BEF) relationships in small plots with model communities established from species pools typically comprising few dozen species. Whether patterns found can be extrapolated to complex, nonexperimental, real-world landscapes that provide ecosystem services to humans remains unclear. Here, we combine species inventories from a large-scale network of 447 1-km² plots with remotely sensed indices of primary productivity (years 2000-2015). We show that landscape-scale productivity and its temporal stability increase with the diversity of plants and other taxa. Effects of biodiversity indicators on productivity were comparable in size to effects of other important drivers related to climate, topography, and land cover. These effects occurred in plots that integrated different ecosystem types (i.e., metaecosystems) and were consistent over vast environmental and altitudinal gradients. The BEF relations we report are as strong or even exceed the ones found in small-scale experiments, despite different community assembly processes and a species pool comprising nearly 2,000 vascular plant species. Growing season length increased progressively over the observation period, and this shift was accelerated in more diverse plots, suggesting that a large species pool is important for adaption to climate change. Our study further implies that abiotic global-change drivers may mediate ecosystem functioning through biodiversity changes. [ABSTRACT FROM AUTHOR]

Intraspecific variation is a major component of biodiversity, yet it has received relatively little attention from governmental and nongovernmental organizations, especially with regard to conservation plans and the management of wild species. This omission is ill-advised because phenotypic and genetic variations within and among populations can have dramatic effects on ecological and evolutionary processes, including responses to environmental change, the maintenance of species diversity, and ecological stability and resilience. At the same time, environmental changes associated with many human activities, such as land use and climate change, have dramatic and often negative impacts on intraspecific variation. We argue for the need for local, regional, and global programs to monitor intraspecific genetic variation. We suggest that such monitoring should include two main strategies: (i) intensive monitoring of multiple types of genetic variation in selected species and (ii) broad-brush modeling for representative species for predicting changes in variation as a function of changes in population size and range extent. Overall, we call for collaborative efforts to initiate the urgently needed monitoring of intraspecific variation. [ABSTRACT FROM AUTHOR]