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Huntington's disease (HD) is the most common monogenic neurodegenerative disease and is fatal. CAG repeat expansions in mutant Huntingtin (mHTT) exon 1 encode for polyglutamine (polyQ) stretches and influence age of onset and disease severity, depending on their length. mHTT is more structured compared to wild-type (wt) HTT, resulting in a decreased N-terminal conformational flexibility. mHTT inflexibility may contribute to both gain of function toxicity, due to increased mHTT aggregation propensity, but also to loss of function phenotypes, due to decreased interactions with binding partners. High-throughput-screening techniques to identify mHTT flexibility states and potential flexibility modifying small molecules are currently lacking. Here, we propose a novel approach for identifying small molecules that restore mHTT's conformational flexibility in human patient fibroblasts. We have applied a well-established antibody-based time-resolved Förster resonance energy transfer (TR-FRET) immunoassay, which measures endogenous HTT flexibility using two validated HTT-specific antibodies, to a high-throughput screening platform. By performing a small-scale compound screen, we identified several small molecules that can partially rescue mHTT inflexibility, presumably by altering HTT post-translational modifications. Thus, we demonstrated that the HTT TR-FRET immunoassay can be miniaturized and applied to a compound screening workflow in patient cells. This automated assay can now be used in large screening campaigns to identify previously unknown HD drugs and drug targets.

Aim: Here we examine the functional profile of regional tree species pools across the latitudinal distribution of Neotropical moist forests, and test trait–climate relationships among local communities. We expected opportunistic strategies (acquisitive traits, small seeds) to be overrepresented in species pools further from the equator, but also in terms of abundance in local communities in currently wetter, warmer and more seasonal climates. Location: Neotropics. Time period: Recent. Major taxa studied: Trees. Methods: We obtained abundance data from 471 plots across nine Neotropical regions, including c. 100,000 trees of 3,417 species, in addition to six functional traits. We compared occurrence-based trait distributions among regional species pools, and evaluated single trait–climate relationships across local communities using community abundance-weighted means (CWMs). Multivariate trait–climate relationships were assessed by a double-constrained correspondence analysis that tests both how CWMs relate to climate and how species distributions, parameterized by niche centroids in climate space, relate to their traits. Results: Regional species pools were undistinguished in functional terms, but opportunistic strategies dominated local communities further from the equator, particularly in the Northern Hemisphere. Climate explained up to 57% of the variation in CWM traits, with increasing prevalence of lower-statured, light-wooded and softer-leaved species bearing smaller seeds in more seasonal, wetter and warmer climates. Species distributions were significantly but weakly related to functional traits. Main conclusions: Neotropical moist forest regions share similar sets of functional strategies, from which local assembly processes, driven by current climatic conditions, select for species with different functional strategies. We can thus expect functional responses to climate change driven by changes in relative abundances of species already present regionally. Particularly, equatorial forests holding the most conservative traits and large seeds are likely to experience the most severe changes if climate change triggers the proliferation of opportunistic tree species.

Ecological restoration of degraded areas can be important to prevent or slow down invasions of alien species. The objective of this study is to evaluate the potential of native species in applying the seeding technique and to compete with the invader Eragrostis plana, aiming ecological restoration at Campos Sulinos grasslands (South Brazil). Seeds of six native species (Anthaenantia lanata, Aristida laevis, Aristida jubata, Chamaecrista repens, Panicum olyroides and Paspalum plicatulum) and of E. plana were sown in isolated and competition (one native species plus the invader) pots. Germination rate, survival rate, germination rate index (GRI), above and belowground biomass were analyzed using ANOVAs and GLMs, and the impact of native species’ attributes at the invader biomass were analyzed using linear regressions. We found that Arista laevis and A. jubata had the highest germination and GRI, although had low survival. Anthaenantia lanata and Paspalum plicatulum had medium germination rate and GRI, but P. plicatulum had high survival and was the only native species to achieve a great biomass development. The invader proved to be a great competitor, with a high GRI, germination and survival rate and biomass production. High germination speed didn’t inhibit the early growth of the invader, although our results show that a high production of native biomass can slow down the development of E. plana. The only native species that was as predominant as the invader at the competition pots was P. plicatulum, and further studies can be important to understand the dynamic between those two species.

A ecologia funcional tem se mostrado uma ferramenta importante em diversos estudos ecologicos. Atributos funcionais respondem a filtros ambientais e influenciam propriedades e funcoes ecossistemicas, podendo ser aplicados em estudos ecologicos voltados a restauracao de ecossistemas. No presente estudo apresentamos como a ecologia funcional pode ser aplicada no âmbito da ecologia da restauracao, desde o planejamento ate o monitoramento dos projetos, com foco no funcionamento dos ecossistemas. O estudo primeiramente contextualiza a teoria ecologica associada a interligacao entre as disciplinas de ecologia da restauracao, funcionamento de ecossistemas e ecologia funcional. Em seguida, apresentamos os resultados de uma pesquisa bibliografica sistematica e descrevemos como a ecologia baseada em atributos funcionais tem sido aplicada no planejamento e monitoramento de projetos de restauracao. Na fase de planejamento, a ecologia funcional auxilia na escolha das especies com base em suas caracteristicas, levando em conta as condicoes ambientais e os potenciais filtros para o desenvolvimento das especies, bem como as metas propostas para o projeto de restauracao. Na fase de monitoramento, os atributos podem ser empregados na avaliacao da funcionalidade do ecossistema, dadas as relacoes entre atributos e processos ecologicos. Concluimos indicando que e importante focar nao so na composicao floristica das comunidades, mas principalmente na manutencao e restauracao das funcoes ecossistemicas, especialmente frente ao cenario de mudancas climaticas e de uso do solo. A interligacao entre restauracao ecologica e funcionamento dos ecossistemas (objetivo comum em projetos de restauracao) pode ser viabilizada atraves de abordagens baseadas em atributos funcionais, aumentando a efetividade na aplicacao de recursos e o sucesso das acoes de restauracao. FUNCTIONAL ECOLOGY AS A TOOL FOR PLANNIG AND MONITORING ECOSYSTEMS RESTORATION: Functional ecology is an important tool in several ecological studies. Functional traits respond to environmental filters and influence ecosystem properties and functions, enabling its application in ecological studies associated with ecosystem restoration. In the present study we present how functional ecology can be applied in restoration ecology, from the planning to the monitoring phases of the project, with the focus on ecosystem functioning. First, the study contextualizes the ecological theory related to the integration of the disciplines of restoration ecology, ecosystem functioning and functional ecology. From that, we present the results of a systematic review of the literature and describe how trait-based ecology has been applied in the planning and monitoring phases of restoration projects. In the planning phase functional ecology helps in selecting species based on their characteristics, considering environmental conditions and potential filters to species development, as well as the targeted aims of restoration projects. In the monitoring phase functional traits can be used in the evaluation of ecosystem functionality, given the relationship between traits and ecological processes. We conclude indicating that it is important to focus not only on community floristic composition, but especially on the maintenance and restoration of ecosystem functions, particularly, in light of the current scenario of climate and land-use change. The integration between restoration ecology and ecosystem functioning – a common goal in ecological restoration projects – can be made through trait-based ecology approaches, increasing the effectiveness in the use of resources and the success of restoration interventions.

Active restoration of grassland ecosystems often requires the addition of species as seeds. However, knowledge of seed germination and initial performance of native species are still lacking in many regions, including the Brazilian grasslands. Regenerative traits (such as seed traits) have the potential to predict performance parameters related to the initial establishment of a species in a given environment. This study aimed to test the potential of regenerative traits as predictors of the performance of grassland species, information which may be useful for ecological restoration purposes. Using 15 grassland species we carried out three parallel experiments at different conditions: cabinet, greenhouse and field. Three performance parameters were evaluated: Final Germination Percentage (FGP), Germination Rate Index (GRI) and survival rate. The suitability of seed traits (mass, area and shape) as predictors of performance parameters was evaluated for each experiment using linear regression models. Performance parameters varied among the species and experiments, but seed mass and shape slightly influenced GRI. Seed area had a positive effect on GRI, and there was a significant interaction between seed circularity and mass, which improved the GRI of round, heavy seeds. FGP and survival rate were not predicted by any of the traits. Our study highlights the importance of testing fitness‐trait relationships under field conditions, which may reflect the real challenges species will face in restoration projects. Our results reinforce the need of considering regenerative traits and interaction factors to improve the understanding and prediction of the initial performance of species.

The species–area relationship is well documented across species in multiple ecosystems, and as such is widely accepted as one of ecology’s key patterns. Although acoustic diversity has generally be...

The multiple land use of agricultural areas is a building block for increased land use efficiency. Unlike monoculture, integrated crop–livestock systems optimally improve ecosystem services, making it an important field of research and application for adapting land use and food systems that have sustainability deficits. The integration of sheep in viticulture production is described as a promising example of an integrated crop–livestock system. While some studies of the integration of sheep into vineyards are already available for other parts of the world, there is still no research on its implementation in Central European viticulture systems. In order to fill this gap of knowledge, we conducted standardized interviews with 34 winegrowers who already graze sheep in their vineyards. The method allowed a wider overview of the implementation of the integrated crop-livestock system than would have been possible with other approaches. Furthermore, the authors kept sheep in their own vineyard for three years to evaluate the statements of the survey participants. The period during which sheep graze in vineyards is quite heterogeneous in Central Europe. Some farms use sheep only during vine dormancy, others also let sheep graze during a certain period in summer. There are also viticulture training systems where grazing is almost continuously possible. In Central Europe, summer grazing normally requires operational adjustments such as lifting the wires of the training system and branches of the vine, otherwise, the vines could be damaged. This option seems to be tailored to the training system in use. Some interviewees mentioned that sheep not only use the accompanying vegetation as fodder and therefore control the undervine growth, but in some cases, they were also able to replace other work processes, such as defoliating the grape zone or cleaning undesired vine shoots near the ground. However, a high additional workload due to livestock keeping was also mentioned by some survey participants. Some of the interviewees cooperate with shepherds, which could help to solve this challenge. Finally, we summarize possible opportunities and risks of this integrated crop–livestock system. Integrating sheep in vineyards seems to be quite feasible in the period of vine dormancy, whereas more information and considerably more effort is needed to integrate sheep during the vegetation period. Further research is needed to answer open questions especially for the necessary adaptions of the common vine training system or the implementation of alternative systems more suitable to combine with livestock keeping. Some practitioners found opportunities to merchandize the use of sheep in wine sales. This potentially unique selling point could be a solution for a broader consideration of sheep in vineyards.

EnglishThe forest expansion process has been observed in forest-grassland mosaics regions in the south of Brazil, mainly over grasslands excluded from cattle grazing and fire. Other factors influence this process, but the magnitude remains almost unknown. Here, we evaluated woody species community patterns on a grassland area, excluded from management for 34 years, relating them to soil and space variables. We established 110 plots (113 m2 each) over areas that were mapped in 1985 as grasslands, in the Estacao Ecologica de Aracuri, Rio Grande do Sul, Brazil. All woody individuals and soil variables were sampled in the plots. Ordination analyses and partial redundancy analysis were applied on these data to meet our aims. Vegetation patterns were better explained by spatial variables, especially concerning the distance from the forest source. Communities closer to the old forest border were characterised by forest species – higher richness and density of zoocoric species. In the most distant border areas, grassland shrubs (Baccharis uncinella) still prevail with few established trees. Although soil had a low proportion of vegetation variance explanation (5%), this situation, however, changes as forest development advances. We conclude that forest expansion in excluded grassland areas is strongly associated with space – the forest source distance and that the effect of soil factors in this process is negligible. portuguesO processo de expansao florestal tem sido observado em regioes de mosaicos de campo-floresta no Sul do Brasil, especialmente em campos excluidos de fogo e pastejo. Outros fatores influenciam esse processo, porem a magnitude ainda permanece pouco compreendida. Neste estudo, avaliamos os padroes da vegetacao lenhosa estabelecida num campo excluido de manejo por 34 anos, relacionando-os com variaveis de solo e espaco. Estabelecemos 110 parcelas (113 m2 cada) de forma sistematica sobre areas mapeadas como campos em 1985, na Estacao Ecologica de Aracuri, Rio Grande do Sul, Brasil. Foram amostrados todos os individuos lenhosos e variaveis de solo. Analises de ordenacao e de particao da variância da composicao de especies nos componentes solo, espaco, e solo estruturado no espaco foram empregadas. Os padroes da vegetacao foram melhor explicados pelo espaco, principalmente a distância da area fonte florestal. Comunidades mais proximas da antiga borda florestal sao caracterizadas por mais especies e individuos com dispersao zoocorica. Areas mais distantes tem predominio de arbustos campestres (Baccharis uncinella) e poucas arboreas se estabeleceram. O solo apresentou baixa explicacao (5%), porem as condicoes modificam-se conforme o desenvolvimento florestal avanca. Concluimos que a expansao florestal em area excluida de disturbios tem forte associacao com o espaco – a distância de areas fonte, e que os fatores edaficos pouco contribuem com a magnitude do avanco sobre o campo.

QUESTIONS: Plant communities in transitional zones between ecosystem types have potentially a large range of ecological strategies, even along short gradients. Exploring these regional differences and the drivers of variation is important to understand plant adaptations and changes in ecological processes between distinct ecosystems. Here, we ask whether distinct forest types in the subtropical region present plant communities with distinct ecological strategies and, if so, if these differences are driven by climatic variables. LOCATION: Subtropical forests in southern Brazil. METHODS: We compiled species lists from 112 sites distributed across rainforests, seasonal forests, Araucaria forests and Pampean forests. We used Grime's CSR scheme and calculated, for each species, CSR values based on information of three leaf traits: leaf area, specific leaf area and leaf dry matter content. Species CSR values were used to calculate the mean value for each community. We selected four climatic variables related to temperate and precipitation and analyzed their influence on plant strategies by linear mixed models. RESULTS: Our results showed a strong CS component for all subtropical forests studied, with a small contribution from component R. We found clear differences in ecological strategies between forest types: rainforest showed the highest values of component C, and Araucaria and Pampean forests presented the highest values of component S. We found a strong influence of temperature variables on ecological strategies. CONCLUSIONS: Even along a short latitudinal gradient, we found differences in ecological strategies across forest types. Araucaria and Pampean forests were strongly associated with the stress‐tolerant strategy, as they face lower minimum temperatures and/or a larger temperature range, whereas rainforests, which face warmer temperatures and a lower range of variation, presented a strategy where competition is of higher importance. This highlights that regional environmental conditions in this transitional zone influence ecological strategies of tree communities.

Tropical forests are converted at an alarming rate for agricultural use and pastureland, but also regrow naturally through secondary succession. For successful forest restoration, it is essential to understand the mechanisms of secondary succession. These mechanisms may vary across forest types, but analyses across broad spatial scales are lacking. Here, we analyse forest recovery using 1,403 plots that differ in age since agricultural abandonment from 50 sites across the Neotropics. We analyse changes in community composition using species-specific stem wood density (WD), which is a key trait for plant growth, survival and forest carbon storage. In wet forest, succession proceeds from low towards high community WD (acquisitive towards conservative trait values), in line with standard successional theory. However, in dry forest, succession proceeds from high towards low community WD (conservative towards acquisitive trait values), probably because high WD reflects drought tolerance in harsh early successional environments. Dry season intensity drives WD recovery by influencing the start and trajectory of succession, resulting in convergence of the community WD over time as vegetation cover builds up. These ecological insights can be used to improve species selection for reforestation. Reforestation species selected to establish a first protective canopy layer should, among other criteria, ideally have a similar WD to the early successional communities that dominate under the prevailing macroclimatic conditions.

QUESTIONS: What is the relative influence of: (a) traits related to dispersal (seed size) and growth (specific leaf area [SLA]), and; (b) regional species abundances, on the structure of local sapling communities? Which metacommunity models best explain the process of forest nucleation in grasslands? LOCATION: Woody vegetation patches originating from nucleation and the continuous forest that neighbors native grasslands, in the southern Brazilian plateau (29°28′58.00″ S, 50°12′26.00″ W). METHODS: We calculated community‐weighted trait means (CWM) and functional diversity for woody saplings, considering species occurrences (FD) and abundances (FDis) separately for both seed size and SLA, in woody vegetation patches of different sizes and in the continuous forest. We tested whether mean SLA and mean seed size differed between habitat types, and whether values of FD and FDis were lower than expected by chance. We also evaluated whether the relative abundances of species in woody vegetation patches were determined by their abundances in the continuous forest, using CATS models (Community Assembly by Trait Selection). The results were then compared to the expectations from each metacommunity model. RESULTS: Functional diversity of SLA and seed size did not differ from what was expected by chance in most sites. Species in communities of different habitat types did not differ in their mean SLA values, but we observed differences in mean seed size, with large‐seeded species being typical of areas with more shade. Species abundances in the regional species pool were more important factors than species traits for determining species abundances in the local communities. CONCLUSIONS: The analytical framework employed in this study enables a straightforward test of different metacommunity structuring models. Mass effects were the metacommunity model that best explained the process of forest nucleation in the southern Brazilian plateau, which highlights the importance of dispersal for the structure of local communities.

Functional traits and species richness have been used to assess variation in ecological functions in multiple ecosystems. However, biodiversity effects on ecosystem functioning could differ between ecosystem types and evaluating these associations could help assess ecosystem recovery in restoration sites. The objective of this study was to analyze the effect of species richness and plant functional traits on ecological processes related to nutrient cycling, productivity and regeneration in subtropical forest ecosystems. The study was performed in three sites (each site containing a reference forest and a forest undergoing restoration) located in the south of Brazil. We collected data on understory abundance, aboveground biomass, litter stock, decomposition, soil feeding activity, litter and soil quality and evaluated the association with tree species richness and plant traits (both community-weighted mean trait values—CWM, and functional diversity measures). Variables related to plant functional traits, especially CWM measures, were associated with most of the ecological processes analyzed. Leaf traits showed the strongest effect on the processes, especially for aboveground biomass, litter stock and understory abundance. Most relationships did not differ between reference and restoration sites. Our results support the mass-ratio theory, suggesting that dominant species traits are the ones that strongly affect ecosystem functioning, and suggest a secondary role of species number on the ecological processes analyzed. Our study provides evidence for the usefulness of functional traits to assess changes in ecological processes in forest ecosystems, with similar patterns in reference forests and forests undergoing restoration.

QUESTIONS: Restoration of grassy biomes is currently of large importance, and controlling invasive grasses is often key to restoring these ecosystems in the tropics and subtropics. We combined different ecological restoration techniques to evaluate potential to control the invasive grass Urochloa decumbens and restore plant species composition. Specific questions were: (a) are herbicide application and topsoil removal efficient to control U. decumbens cover and allow native species establishment; and (b) are hay transfer and sowing native grass species efficient to reintroduce native species and increase their cover? LOCATION: Campos grasslands, southern Brazil. METHODS: We combined the follow restoration techniques: (a) herbicide application or topsoil removal to control the invasive species, and (b) hay transfer or sowing of native grasses to reintroduce native species. We assessed and compared native plant species richness, vegetation cover, native species cover, U. decumbens cover and other exotic species cover in 2016 and 2017. RESULTS: Herbicide application reduced invasive species cover more than topsoil removal, even though both were effective. The decrease of U. decumbens cover led to an increase in native species cover and native species richness. Hay transfer and sowing native grasses did not produce satisfactory results for native species reintroduction. Native species richness and U. decumbens cover increased from 2016 to 2017. CONCLUSION: Herbicide application was a better option to control U. decumbens and to allow recovery of native species. However, use of herbicides in restoration is controversial, and more detailed studies on impacts are necessary. Environmental filters appear to be a major cause for failure of hay transfer and seeding species. Recovery of the native plant community is a great challenge in invaded subtropical grasslands, and additional management actions and time are necessary to increase the establishment of native species.

The Brazilian coastal plains comprise very different forest types commonly distinguished by soil conditions. The study of distinct life-forms in the herb layer might contribute to the understanding of forest structure and to the circumscription of forest types. In this paper, we investigated the variation in composition and diversity of the herb layer in three coastal forest types (Dune, Peat and Rain forests) within the Brazilian Atlantic Forest complex and examined if coastal forests’ differences, usually characterized by adult trees, are matched by herb layer features. We sampled the herb layer (≤1 m in height) in 23 forest fragments, classifying species in climbers, herbs, palms, shrubs and trees. Peat forest had lower overall diversity relative to Dune and Rain forests. Higher tree species richness and abundance in Rain forest, and higher herbaceous richness and abundance in Peat forest were the major differences between these forest types. Dune forest was similar to Peat forest in relation to herbaceous species and to Rain forest in relation to tree species indicating a transition environment between both forests. Composition between forests is distinguishable for trees and shrubs, but not for climbers and herbaceous species. Thus, the distinctions among these forest types are complex when taking into account the herb layer. Our findings demonstrate the importance of including the herb layer life-forms for a better understanding of the diversity and complexity of tropical and subtropical forests, especially the Atlantic coastal forests, which should be primarily classified as flooded and non-flooded at a regional scale.

To date, there are no published guidelines on how to optimally install recorders on sloped terrain, although slope could potentially affect a recorder’s detection space. This study experimentally investigated the effect of microphone orientation in relation to slope of recorders from two cost classes. We installed four recorders at each plot centre (n = 16), oriented either parallel or perpendicular to the slope. We played standard tones of 1–11 kHz at distances of 10, 20, 40 and 80 m from the recorders. Our two response variables were the presence/absence of each tone (coarse spatial scale) and predicted sound extinction distance (fine spatial scale), which were tested for effects of microphone orientation and sound source direction (SSD). We observed a significant effect of microphone orientation on extinction distance when recorders were perpendicular to the slope at the finer spatial scale as an interaction with SSD, indicating that microphones are biased towards the direction they face. Despite the advertised directionality of most recorder microphones, detection space is not circular. This trend was observed across all frequencies, for both high- and low-cost recorders. Microphone orientation in relation to slope is not an important methodological consideration, instead dominant factors such as frequency and prevailing wind direction drive detection space shape.

One-third of all Neotropical forests are secondary forests that regrow naturally after agricultural use through secondary succession. We need to understand better how and why succession varies across environmental gradients and broad geographic scales. Here, we analyze functional recovery using community data on seven plant characteristics (traits) of 1,016 forest plots from 30 chronosequence sites across the Neotropics. By analyzing communities in terms of their traits, we enhance understanding of the mechanisms of succession, assess ecosystem recovery, and use these insights to propose successful forest restoration strategies. Wet and dry forests diverged markedly for several traits that increase growth rate in wet forests but come at the expense of reduced drought tolerance, delay, or avoidance, which is important in seasonally dry forests. Dry and wet forests showed different successional pathways for several traits. In dry forests, species turnover is driven by drought tolerance traits that are important early in succession and in wet forests by shade tolerance traits that are important later in succession. In both forests, deciduous and compound-leaved trees decreased with forest age, probably because microclimatic conditions became less hot and dry. Our results suggest that climatic water availability drives functional recovery by influencing the start and trajectory of succession, resulting in a convergence of community trait values with forest age when vegetation cover builds up. Within plots, the range in functional trait values increased with age. Based on the observed successional trait changes, we indicate the consequences for carbon and nutrient cycling and propose an ecologically sound strategy to improve forest restoration success.

It has been increasingly argued that ecological restoration should focus more on targeting ecosystem services than on species composition of reference ecosystems. In this sense, the role that species play on community assembly and functioning through their functional traits is very relevant, because effect traits mediate ecosystem processes, ultimately resulting in provision of ecosystem services. One major challenge in ecological restoration is to know which species to use that will deliver the target ecosystem services. We developed an algorithm to select the minimum set of species that maximize the functional richness (FRic) and the functional redundancy (FR) of the restored community, a proxy for the provision of multiple ecosystem services and the resilience of the system to environmental changes, respectively. For this, we simulated the restoration of 24 riparian woody communities of the Brazilian Cerrado. Using the species pool of each original local community, we ran restoration simulations for gradually increasing species richness until reaching the total species richness of the original local community. We computed FRic and FR for each simulated restoration community using the traits specific leaf area, maximum plant height and seed mass. Our simulation results indicate that multiple ecosystem services could be restored with an average of 66% of the species of the original community. Moreover, an average of 59% of the species would be needed to restore communities resilient to environmental changes. Our approach contributes to solving one of the major challenges of ecological restoration, which is defining how many and which species should be used to achieve functional targets. We believe this approach can help in projects of restoration by enabling restoration practitioners to select minimum alternative sets of species that optimize the provision of multiple ecosystem services in a resilient restored ecosystem.

[Background]: In contrast with the negligible contribution of the forest understorey to the total aboveground phytobiomass of a forest, its share in annual litter production and nutrient cycling may be more important. Whether and how this functional role of the understorey differs across forest types and depends upon overstorey characteristics remains to be investigated., [Methods]: We sampled 209 plots of the FunDivEUROPE Exploratory Platform, a network of study plots covering local gradients of tree diversity spread over six contrasting forest types in Europe. To estimate the relative contribution of the understorey to carbon and nutrient cycling, we sampled non-lignified aboveground understorey biomass and overstorey leaf litterfall in all plots. Understorey samples were analysed for C, N and P concentrations, overstorey leaf litterfall for C and N concentrations. We additionally quantified a set of overstorey attributes, including species richness, proportion of evergreen species, light availability (representing crown density) and litter quality, and investigated whether they drive the understorey’s contribution to carbon and nutrient cycling. [Results and conclusions]: Overstorey litter production and nutrient stocks in litterfall clearly exceeded the contribution of the understorey for all forest types, and the share of the understorey was higher in forests at the extremes of the climatic gradient. In most of the investigated forest types, it was mainly light availability that determined the contribution of the understorey to yearly carbon and nutrient cycling. Overstorey species richness did not affect the contribution of the understorey to carbon and nutrient cycling in any of the investigated forest types., [Results and conclusions]: Overstorey litter production and nutrient stocks in litterfall clearly exceeded the contribution of the understorey for all forest types, and the share of the understorey was higher in forests at the extremes of the climatic gradient. In most of the investigated forest types, it was mainly light availability that determined the contribution of the understorey to yearly carbon and nutrient cycling. Overstorey species richness did not affect the contribution of the understorey to carbon and nutrient cycling in any of the investigated forest types., This study was performed within the framework of the FunDivEUROPE project and has received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement n° 265171. Dries Landuyt was supported by a postdoctoral fellowship of the Research Foundation-Flanders (FWO). Kris Verheyen was supported by the ERC Consolidator Grant 614839 that is linked with the project PASTFORWARD.

Extensive invasion of the Campos grasslands of southern Brazil by the South African grass, Eragrostis plana, is a serious conservation problem due to its low palatability and ability to quickly spread. Here, we experimentally evaluated the effects of grazing management and initial disturbance on invasibility of native grassland community by E. plana. The experiment, a split-plot complete block design with three replications, was established in 2004 in non-invaded native grassland. Grazing management treatments were assessed in main plots (continuous grazing, rotational grazing, and grazing exclusion). The initial disturbance treatments (light grazing, heavy grazing, and heavy grazing plus soil scarification) were applied in subplots before the sowing of standard amounts of E. plana seeds. The initial disturbances heavy grazing and heavy grazing plus soil scarification simulated the introduction of exotic forage species. We monitor plant species composition and diversity along six years after the experiment starting. The effects of grazing management and initial disturbance on community invasibility were significant and showed interaction. Heavy grazing plus soil scarification increased the rate of E. plana invasion and produced more pronounced changes in species composition than the other treatments. Plots under grazing exclusion, rotational or continuous grazing without soil scarification had low levels of invasion (

Given the key role of belowground biota on forest ecosystem functioning, it is important to identify the factors that influence their abundance and composition. However, the understanding of the ecological linkage between tree diversity and belowground biota is still insufficient. Here we investigated the influence of tree diversity (richness, True Shannon diversity index, functional diversity) and identity (proportion of evergreen leaf litter and leaf litter quality) on earthworm species richness and biomass at a continental and regional scale, using data from a Europe-wide forest research platform (FunDivEUROPE) spanning six major forest types. We found a marked tree identity effect at the continental scale, with proportion of evergreen leaf litter negatively affecting total earthworm biomass and species richness, as well as their biomass per functional group. Furthermore, there were clear litter quality effects with a latitudinal variation in trait-specific responses. In north and central Europe, earthworm biomass and species richness clearly increased with increasing litter nutrient concentrations (decreasing C:N ratio and increasing calcium concentration), whereas this influence of litter nutrients was absent or even reversed in southern Europe. In addition, although earthworms were unaffected by the number of tree species, tree diversity positively affected earthworm biomass at the continental scale through functional diversity of the leaf litter. By focusing on tree leaf litter traits, this study advanced our understanding of the mechanisms driving tree identity effects and supported previous findings that litter quality, as a proxy of tree identity, was a stronger driver of earthworm species richness and biomass than tree diversity.

Subtropical forests certainly contribute to terrestrial global carbon storage, but we have limited understanding about the relative amounts and of the drivers of above-ground biomass (AGB) variation in their region. Here we assess the spatial distribution and drivers of AGB in 119 sites across the South American subtropical forests. We applied a structural equation modelling approach to test the causal relationships between AGB and environmental (climate and soil), structural (proportion of large-sized trees) and community (functional and species diversity and composition) variables. The AGB on subtropical forests is on average 246 Mg ha−1. Biomass stocks were driven directly by temperature annual range and the proportion of large-sized trees, whilst soil texture, community mean leaf nitrogen content and functional diversity had no predictive power. Temperature annual range had a negative effect on AGB, indicating that communities under strong thermal amplitude across the year tend to accumulate less AGB. The positive effect of large-sized trees indicates that mature forests are playing a key role in the long-term persistence of carbon storage, as these large trees account for 64% of total biomass stored in these forests. Our study reinforces the importance of structurally complex subtropical forest remnants for maximising carbon storage, especially facing future climatic changes predicted for the region.

Ecological restoration should focus, not only on species composition, but also on the ecological functions provided by the ecosystem, mirroring the characteristics found in the reference site. In this context, plant functional traits could help to achieve this goal, as they directly affect ecosystem processes. Thus, modeling species composition based on species functional traits could provide ways to make predictions about future communities and to assess the functioning of the ecosystem. In order to evaluate how different restored communities are from their reference ecosystem, we used a trait-based modeling approach that predicts relative abundances of a community based on the functional composition of the reference ecosystem. We surveyed adult trees in the canopy and seedlings in the understory in both reference and 10 year-old restoration sites in two different locations in South of Brazil to gather information of species composition and their relative abundances. Functional composition was based on information of leaf traits for all species included in the survey. We applied the model on two different components: canopy and understory species. We found differences in functional composition between the restored communities and the reference sites, indicating that the ten-year old restored forests are still not similar to the reference ecosystem. Both the observed and the predicted understory communities were more similar to the reference ecosystem than the observed canopy communities. It indicates that species that established after restoration interventions have functional composition closer to the reference ecosystem than the set of species initially selected for planting. Modeling the community based on functional trait composition coupled with long-term monitoring of sites undergoing restoration would enable a better evaluation of restoration trajectories and management needs to modify ecosystem functions towards values found in reference sites. Restoration should focus on the recovery of functional composition, which would provide a better set of resources for organisms and promote changes in ecosystem processes.

Understanding the processes that drive patterns of beta diversity is crucial for planning conservation policies and for designing networks of protected area (PAs). Beta diversity can be decomposed into two components: 1—species turnover, the replacement of species by others resulting in a low proportion of shared species; 2—species nestedness—the result of differences in species richness, when a poorer community is a subset of species from a richer community. We aimed to evaluate beta diversity patterns and how they are represented in the network of PAs in southern Brazilian, regarding three forest types: Atlantic Forest s.s., Araucaria Forest, and Seasonal Forest. Beta diversity was partitioned into the turnover and nestedness components. Additionally, we examined spatial patterns of site similarity using distance decay curves. Beta diversity was mainly caused by species turnover (approx. 86%), with only a small contribution of nestedness (approx. 5%) in all three forests types. The patterns of distance decay curves revealed that even at small distances (50–100 km), we found a considerable decrease in similarities, reinforcing turnover patterns. As turnover brought the larger contribution to beta diversity, additional conservation efforts must target an increase in the number of PAs, that should be spread across each one of the regions, to maximize the protection of species diversity. Most of the PAs are currently limited to the eastern region and prioritize the Atlantic Forest s.s. Thus Araucaria Forest and Seasonal Forest should deserve special priority in new conservation actions, as they also contain high levels of species turnover.

Summary Different tree species influence litter decomposition directly through species-specific litter traits, and indirectly through distinct modifications of the local decomposition environment. Whether these indirect effects on decomposition are influenced by tree species diversity is presently not clear. We addressed this question by studying the decomposition of two common substrates, cellulose paper and wood sticks, in a total of 209 forest stands of varying tree species diversity across six major forest types at the scale of Europe. Tree species richness showed a weak but positive correlation with the decomposition of cellulose but not with that of wood. Surprisingly, macroclimate had only a minor effect on cellulose decomposition and no effect on wood decomposition despite the wide range in climatic conditions among sites from Mediterranean to boreal forests. Instead, forest canopy density and stand-specific litter traits affected the decomposition of both substrates, with a particularly clear negative effect of the proportion of evergreen tree litter. Our study suggests that species richness and composition of tree canopies modify decomposition indirectly through changes in microenvironmental conditions. These canopy-induced differences in the local decomposition environment control decomposition to a greater extent than continental-scale differences in macroclimatic conditions.

A functional perspective of tree communities is helpful for understanding forest dynamics, especially vegetation recovery after other land uses. Knowledge about ecological filters and survival strategies of trees are also important for the restoration of degraded areas. This study aimed to evaluate the functional composition and structure of adult and regenerative components of natural Araucaria forests, Araucaria plantations and plantations of exotic Pinus in subtropical southern Brazil. Differences in functional diversity and functional richness, and in community weighted mean trait values, including leaf traits and reproductive traits, were analyzed. RLQ analysis was used to assess the association between community structure, plant traits and environmental variables. Clear differences were found for most traits and for functional richness for the regenerative component, while the adult component was more similar among forest types. A clear separation in RLQ ordination associated with trait variation, for the adult component but not for regenerative trees, also indicates that communities are becoming functionally more similar with time. Plantations were shown to function as environmental filters by directly influencing species recruitment, richness and functional diversity. We conclude that passive restoration may be the best strategy for restoration of Araucaria forests.

Subtropical Campos Sulinos grasslands, in South Brazil, are among the most biodiverse grasslands of the world. As climatic conditions lead to high productivity, disturbance are critical to maintain their diversity. Long-term exclusion, on the other hand, leads to plant species losses and changes in composition. No studies on the restoration of these grasslands after abandonment exist to date. We tested combinations of restoration techniques with the aim of increasing plant diversity in an abandoned and species-poor grassland in the South Brazilian highland region. In a bi-factorial experiment, we tested the effects of two different frequencies of mowing and of hay transfer. Mowing reduced plant cover, vegetation height, and abundance of erect grasses and shrubs, and increased species richness, diversity (Shannon diversity index) and prostrate forb and grass cover. No differences were found between mowing frequencies. Hay transfer was not effective at reintroducing species. The results of the present study provide further evidence that the reintroduction of plants is a major challenge in the restoration of subtropical and tropical grasslands. The study shows that mowing is a fast way to increase plant diversity in Campos Sulinos after long periods of abandonment.

Tropical secondary forests recover quickly (decades) in tree species richness but slowly (centuries) in species composition., Old-growth tropical forests harbor an immense diversity of tree species but are rapidly being cleared, while secondary forests that regrow on abandoned agricultural lands increase in extent. We assess how tree species richness and composition recover during secondary succession across gradients in environmental conditions and anthropogenic disturbance in an unprecedented multisite analysis for the Neotropics. Secondary forests recover remarkably fast in species richness but slowly in species composition. Secondary forests take a median time of five decades to recover the species richness of old-growth forest (80% recovery after 20 years) based on rarefaction analysis. Full recovery of species composition takes centuries (only 34% recovery after 20 years). A dual strategy that maintains both old-growth forests and species-rich secondary forests is therefore crucial for biodiversity conservation in human-modified tropical landscapes.

Functional diversity informs about biodiversity-ecosystem functioning relationships. The intraspecific component of functional diversity (i.e. the phenotypic space of each species) depicts individual differences in the resource use and fitness among conspecifics, and gives valuable information about the functional similarity (competition) or dissimilarity (complementarity) of coexisting species. Here, we quantified trait differences within tree species along local diversity gradients to shed light on the role that this intraspecific variability exerts on functional complementarity of tree species. We measured architectural traits in 5,036 individuals and leaf traits in 1,403 individuals from nine dominant tree species, surveyed in 92 plots located in three major European forest types (Mediterranean, temperate and boreal forests). In each forest type, plots were positioned along a canopy richness gradient, with every study species present in different species richness levels, including monocultures. Our results showed that the relative magnitude of intraspecific trait variability to community-level variability is high in these forests. At the species level, we found adjustments of species leaf traits (mean shifts) in response to neighbouring trees, suggesting the existence of processes that limit niche overlap. We also found higher variability in architectural traits of conspecific individuals in more diverse canopies, suggesting greater niche packing and a more efficient use of available space as the number of species in the canopy increases. Altogether, our results support the hypothesis that differential responses of individuals within a species promote species complementarity, suggesting that biodiversity-ecosystem functioning relationships cannot be properly estimated without accounting for the intraspecific level of functional variation., All authors acknowledge support from the European Union FunDivEUROPE project (FP7-ENV-2010. Grant agreement No. 265171). RB was funded by a Marie Curie IEF fellowship (DIVEFOR. FP7-PEOPLE-2011-IEF. Grant Agreement No. 302445), together with the European Union's Horizon 2020 Research and Innovation Programme Project GenTree (Grant Agreement No. 676876), and REMEDINAL3-CM (Autonomous Community of Madrid, S2013/MAE-2719), LINCGlobal (4540-143AP), COMEDIAS (CGL2017-83170-R, Spanish Ministry of Science, Innovation and Universities) projects.

Made available in DSpace on 2019-10-04T12:14:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-05-23 Fundacao Grupo Boticario de Protecao a Natureza Financiadora de Estudos e Projetos Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Background: Araucaria forests are mountain ecosystems that might have expanded in the late Holocene, however past distributions remain uncertain. If current distribution reflects climatic conditions, past and future distributions may be projected using climate models. Aims: To contribute to the understanding of past and future distribution of Araucaria forests as a function of climate, we hypothesised that (1) they have increased their geographic distribution since the Last Glacial Maximum (LGM) until the present; and (2) would contract under predicted future climates. Methods: We modelled the spatial distributions of Araucaria forests under current, past and future climatic scenarios. Ecological niche models of 12 indicator species were developed using ensemble modelling. Results: The greatest extent of distribution of Araucaria forests appeared to have occurred during the LGM, after which a continuous retraction followed until the present. Our models suggested that Araucaria forests would experience an even greater retraction in the future. Conclusion: Araucaria forests could have covered larger areas during the LGM than suggested by earlier palynological studies, because climate was suitable for their distribution. The degree of loss of modelled distribution area since the LGM until today indicate these forests are likely to continue to shrink under projected future climatic changes. Univ Fed Rio Grande do Sul, Lab Ecol Vegetal, Programa Posgrad Ecol, Porto Alegre, RS, Brazil Univ Fed Goias, Lab Bioge, Goiania, Go, Brazil Univ Fed Rio Grande do Sul, Lab Ecol Quantitat, Porto Alegre, RS, Brazil Univ Estadual Paulista, Lab Herpetol, Sao Paulo, Brazil Univ Fed Rio Grande do Sul, Lab Ecol Paisagem, Porto Alegre, RS, Brazil FBDS, Rio De Janeiro, RJ, Brazil Univ Estadual Paulista, Lab Herpetol, Sao Paulo, Brazil Fundacao Grupo Boticario de Protecao a Natureza: PROG_0008_2013 Financiadora de Estudos e Projetos: 01.13.0353.00 CAPES: 1561948 CAPES: 1562642 FAPESP: 2014/22344-6 CNPq: 140764-2013-5 CNPq: 307719/2012-0 CNPq: 308532/2014-7 CNPq: 407094/2013-0 CNPq: 437167/2016-0 CNPq: 479959/2013-7 CNPq: 563621/2010-9

Functional analysis of secondary succession may allow identifying and predicting processes of community assembly, which can be simultaneously driven by factors related to ecological filters and neutral forces. This study evaluated trait-convergence assembly patterns and trait-divergence assembly patterns in successional areas of Araucaria forest. Plant species were sampled in both the upper and lower strata and were described by 15 functional traits. Data analyses were based on multiplication and Procrustes adjustment of matrices, which permit to discriminate trait-convergence assembly patterns and trait-divergence assembly patterns along the forest succession (our environmental variable), and the influence of phylogeny on these patterns. Initial and late forests were highly different in species composition, but the regenerating stratum was already more similar especially in functional terms. Traits related to the acquisitive-conservative trade-off (wood density, leaf nitrogen content, leaf area, leaf dry matter content) revealed strong convergent patterns of successional changes. Moreover divergence was maximized by specific leaf area, seed mass, deciduousness, and dispersal mode, showing a higher functional diversity in late Araucaria forests.

This study evaluated the influence of vegetation structure on bird diversity, guilds, and the richness and composition of species in different successional stages of the subtropical Atlantic rain forest. Much of the land that was formerly agricultural in the Brazilian Atlantic rain forest region is now given over to secondary forests. The habitat structure of these successional forests vary and are influenced by time, historical use and local variables, all of which affect bird assemblies. Sampling of bird species was carried out through audio-visual point counts conducted in forests varying from six years after abandonment to old-growth areas. Forests in which the point counts were conducted were further classified into initial, intermediate and advanced stages according to 11 vegetation structural variables, through cluster analyses. The study found that bird richness and diversity were similar between initial and intermediate stages, but higher in advanced areas. Bird species composition differed betwe...