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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. ; Peer reviewed

This research is part of POLARCSIC activities.-- 15 pages, 9 figures, 3 tables, supplementary data https://doi.org/10.1016/j.jmarsys.2019.103268 ; The flow of non-living carbon (detritus) is considered an important process because it connects ecosystems and fuels benthic communities. In Norwegian kelp forests, 90% of the kelp production is exported to adjacent ecosystems where it can play a significant role in shaping benthic communities. We quantified the major structural and functional traits of an Arctic deep-sea ecosystem associated with kelp exports and assessed the ecological role of kelp export into the deep-sea system. We first developed a food-web model using the Ecopath with Ecosim (EwE) approach to represent the state of the deep (450 m) ecosystem of the Malangen fjord (Northern Norway) in 2017. Subsequently, we used the temporal dynamic model Ecosim to explore the structure and functioning traits of a theoretical deep-sea ecosystem projecting a decrease of kelp detritus biomass reaching the deep-sea ecosystem. Overall, our findings reveal that kelp detritus from shallow coastal areas has a small but noticeable role structuring the deep-sea ecosystem of Malangen. The temporal simulations show important differences depending on the application of mediating effects, which allow considering the detritus as a mediating group in prey-predator interaction, in addition to its direct role in trophic relationships. When mediating effects are applied, biomass increases for benthopelagic shrimps and suprabenthos groups and decreases for rays and skates, velvet belly, rabbitfish and other commercial demersal fishes under the low kelp detritus scenarios. Biomass-based and trophic-based indicators reveal a noticeable impact on the deep-sea ecosystem structure due to depletion of kelp detritus. To further assess future changes of the Arctic deep-sea ecosystems, dependencies with adjacent ecosystems, such as kelp detritus production, should be included ; This work was funded by MARINFORSK Norwegian Research Council through the KELPEX project (NRC Grant no. 255085/E40). [.] MC acknowledges partial funding by the European Union's Horizon research program grant agreement No 689518 for the MERCES project

The prediction of carbon uptake by forests across fertility gradients requires accurate characterisation of how biochemical limitations to photosynthesis respond to variation in key elements such as nitrogen (N) and phosphorus (P). Over the last decade, proxies for chlorophyll and photosynthetic activity have been extracted from hyperspectral imagery and used to predict important photosynthetic variables such as the maximal rate of carboxylation (Vcmax) and electron transport (Jmax). However, little research has investigated the generality of these relationships within the nitrogen (N) and phosphorus (P) limiting phases, which are characterised by mass based foliage ratios of N:P ≤ 10 for N limitations and N:P > 10 for P limitations. Using measurements obtained from one year old Pinus radiata D. Don grown under a factorial range of N and P treatments this research examined relationships between photosynthetic capacity (Vcmax, Jmax) and measured N, P and chlorophyll (Chla+b). Using functional traits quantified from hyperspectral imagery we then examined the strength and generality of relationships between photosynthetic variables and Photochemical Reflectance Index (PRI), Sun-Induced Chlorophyll Fluorescence (SIF) and chlorophyll a + b derived by radiative transfer model inversion. There were significant (P < .001) and strong relationships between photosynthetic variables and both N (R2 = 0.82 for Vcmax; R2 = 0.87 for Jmax) and Chla+b (R2 = 0.85 for Vcmax; R2 = 0.86 for Jmax) within the N limiting phase that were weak (R2 < 0.02) and insignificant within the P limiting phase. Similarly, there were significant (P < .05) positive relationships between P and photosynthetic variables (R2 = 0.50 for Vcmax; R2 = 0.58 for Jmax) within the P limiting phase that were insignificant and weak (R2 < 0.33) within the N limiting phase. Predictions of photosynthetic variables using Chla+b estimated by model inversion were significant (P < .001), positive and strong (R2 = 0.64 for Vcmax; R2 = 0.63 for Jmax) within the N limiting phase but insignificant and weak (R2 < 0.05) within the P limiting phase. In contrast, both SIF and PRI exhibited moderate to strong positive correlations with photosynthetic variables within both the N and P limiting phases. These results suggest that quantified SIF and PRI from hyperspectral images may have greater generality in predicting biochemical limitations to photosynthesis than proxies for N and chlorophyll a + b, particularly under high foliage N content, when P is limiting. ; Resilient Forests programme Scion SSIF Forest Grower's Levy Trust National Institute for Forest Products Innovation NIF073-1819 Australian Government CGIAR Australasian Forestry Companies South Australian State Government Tasmanian State Government

Functional diversity (FD) has the potential to address many ecological questions, from impacts of global change on biodiversity to ecological restoration. There are several methods estimating the different components of FD. However, most of these methods can only be computed at limited spatial scales and cannot account for intraspecific trait variability (ITV), despite its significant contribution to FD. Trait probability density (TPD) functions (which explicitly account for ITV) reflect the probabilistic nature of niches. By doing so, the TPD approach reconciles existing methods for estimating FD within a unifying framework, allowing FD to be partitioned seamlessly across multiple scales (from individuals to species, and from local to global scales), and accounting for ITV. We present methods to estimate TPD functions at different spatial scales and probabilistic implementations of several FD concepts, including the primary components of FD (functional richness, evenness, and divergence), functional redundancy, functional rarity, and solutions to decompose beta FD into nested and unique components. The TPD framework has the potential to unify and expand analyses of functional ecology across scales, capturing the probabilistic and multidimensional nature of FD. The R package TPD (https://CRAN.R-project.org/package=TPD) will allow users to achieve more comparative results across regions and case studies. ; CPC was supported by the Estonian Research Council (project PSG293), and by the European Union through the European Regional Development Fund (Centre of Excellence EcolChange)

O bioma Cerrado abriga mais de 12.000 espécies vegetais nativas, distribuídas em 11 fitofisionomias, incluindo áreas campestres, savânicas e florestais. Essa diversidade de ambientes confere às plantas nativas traços funcionais específicos. Para investigar esses traços funcionais, realizou-se uma pesquisa na base de dados Web of Science, o que resultou no total de 1227 publicações, das quais 482 foram retidas para análise após a aplicação de critérios de filtragem. Foram empregados métodos de cienciometria para a obtenção de métricas de publicação e análise de conteúdo dos artigos. Observou-se que os traços funcionais mais frequentes nas publicações estão relacionados às temáticas como fenologia, fotossíntese, ocorrência de fogo, herbivoria, polinização, área foliar, carbono, capacidade de rebrota, concorrência, adaptações à seca, anatomia vegetal e dispersão de sementes. O número de publicações foi crescente durante o período analisado (1991-2022), principalmente a partir do ano 2011, com ao menos 20 artigos publicados anualmente. Os temas básicos de pesquisa foram Cerrado, mudança climática, ecologia do fogo e déficit hídrico, os temas motores incluíram assuntos relacionados, principalmente, à fotossíntese e mudança climática. Com base nas análises, observa-se que os traços funcionais podem ser classificados em demográficos, fenológicos, fisiológicos, morfológicos, morfofenológicos e morfofisiológicos. Apesar deste estudo ser abrangente, ressalta-se que o número de artigos publicados investigando os traços funcionais de plantas nativas do Cerrado é incipiente, principalmente diante das rápidas alterações de uso e cobertura da terra que ocorrem no bioma e que podem afetar significativamente a flora. São necessários mais estudos para gerar conhecimentos e preencher as lacunas em relação às respostas e adaptações das plantas do bioma às diferentes condições e limitações ambientais, principalmente em um cenário de mudança climática, alterações no uso do solo, fragmentação de habitats, invasão de ambientes naturais por espécies exóticas e contaminação por agroquímicos.