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A new framework for measuring functional diversity (FD) from multiple traits has recently been proposed. This framework was mostly limited to quantitative traits without missing values and to situations in which there are more species than traits, although the authors had suggested a way to extend their framework to other trait types. The main purpose of this note is to further develop this suggestion. We describe a highly flexible distance‐based framework to measure different facets of FD in multidimensional trait space from any distance or dissimilarity measure, any number of traits, and from different trait types (i.e., quantitative, semi‐quantitative, and qualitative). This new approach allows for missing trait values and the weighting of individual traits. We also present a new multidimensional FD index, called functional dispersion (FDis), which is closely related to Rao's quadratic entropy. FDis is the multivariate analogue of the weighted mean absolute deviation (MAD), in which the weights are species relative abundances. For unweighted presence–absence data, FDis can be used for a formal statistical test of differences in FD. We provide the “FD” R language package to easily implement our distance‐based FD framework.

The concept of plant functional traits has been demonstrated to be very effective in unravelling the ecological mechanisms governing plant community response to disturbance, especially when research is focused onshort-term post-disturbance vegetation dynamics. In this study, we established an experiment to quantify how logging intensity affects the trait composition and functional diversity of understory communities in fir-beechforests in the Dinaric Mountains in Slovenia. Three different silvicultural treatments were implemented: control (no logging), 50% of the growing stock removed and 100% of the growing stock removed. Vegetation surveys of vascular plants were made before (in 2012) and two years after (in 2014) logging. Changes in species traits, C-S-R plant strategies (sensu Grime) and community-level functional diversity were analysed. The importance of traits such as small and light diaspores, short life span and anemochory increased with logging intensity. Moreover, species with the ability of both sexual and vegetative reproduction, longer flowering duration and overwintering green leaves increased in abundance after logging. C-S-R strategies mainly shifted from stress-tolerators in pre-logging conditions towards a more ruderal component in post-logging stands. Logging in the short term increased functional diversity, mainly due to newly colonized species being functionally dissimilar from persistent residents. Results suggest that logging intensity strongly influences the magnitude of change in both functional composition and diversity, which also has important implications for biodiversity conservation. At the landscape scale, increasing spatial heterogeneity by creating a mosaic of forest stands subjected to different logging intensities will likely contribute to the enhancement of plant functional diversity.

Tropical forests vary widely in biomass carbon (C) stocks and fluxes even after controlling for forest age. A mechanistic understanding of this variation is critical to accurately predicting responses to global change. We review empirical studies of spatial variation in tropical forest biomass, productivity and woody residence time, focusing on mature forests. Woody productivity and biomass decrease from wet to dry forests and with elevation. Within lowland forests, productivity and biomass increase with temperature in wet forests, but decrease with temperature where water becomes limiting. Woody productivity increases with soil fertility, whereas residence time decreases, and biomass responses are variable, consistent with an overall unimodal relationship. Areas with higher disturbance rates and intensities have lower woody residence time and biomass. These environmental gradients all involve both direct effects of changing environments on forest C fluxes and shifts in functional composition – including changing abundances of lianas – that substantially mitigate or exacerbate direct effects. Biogeographic realms differ significantly and importantly in productivity and biomass, even after controlling for climate and biogeochemistry, further demonstrating the importance of plant species composition. Capturing these patterns in global vegetation models requires better mechanistic representation of water and nutrient limitation, plant compositional shifts and tree mortality.

Ecological disturbance is fundamental to the dynamics of biological communities, yet a conceptual framework for understanding the responses of faunal communities to disturbance remains elusive. Here, I propose five principles for understanding the disturbance dynamics of ants—a globally dominant faunal group that is widely used as bioindicators in land management, which appear to have wide applicability to other taxa. These principles are as follows: (1) The most important effects of habitat disturbance on ants are typically indirect, through its effects on habitat structure, microclimate, resource availability and competitive interactions; (2) habitat openness is a key driver of variation in ant communities; (3) ant species responses to disturbance are to a large degree determined by their responses to habitat openness; (4) the same disturbance will have different effects on ants in different habitats, because of different impacts on habitat openness; and (5) ant community responses to the same disturbance will vary according to ant functional composition and biogeographical history in relation to habitat openness. I illustrate these principles using results primarily from studies of ant responses to fire, a dominant agent of disturbance globally, to provide a common disturbance currency for comparative analysis. I argue that many of the principles also apply to other faunal groups and so can be considered as general ecological “laws.” As is the case for ants, many impacts of habitat disturbance on other faunal groups are fundamentally related to habitat openness, the effects of disturbance on it and the functional composition of species in relation to it. This article provides a novel conceptual framework for a predictive understanding of the disturbance dynamics of ants, a globally dominant faunal group. The framework is based on five principles that appear to be widely applicable to fauna in general and therefore qualify as general ecological “laws.”

Africa is forecasted to experience large and rapid climate change 1 and population growth 2 during the twenty-first century, which threatens the world’s second largest rainforest. Protecting and sustainably managing these African forests requires an increased understanding of their compositional heterogeneity, the environmental drivers of forest composition and their vulnerability to ongoing changes. Here, using a very large dataset of 6 million trees in more than 180,000 field plots, we jointly model the distribution in abundance of the most dominant tree taxa in central Africa, and produce continuous maps of the floristic and functional composition of central African forests. Our results show that the uncertainty in taxon-specific distributions averages out at the community level, and reveal highly deterministic assemblages. We uncover contrasting floristic and functional compositions across climates, soil types and anthropogenic gradients, with functional convergence among types of forest that are floristically dissimilar. Combining these spatial predictions with scenarios of climatic and anthropogenic global change suggests a high vulnerability of the northern and southern forest margins, the Atlantic forests and most forests in the Democratic Republic of the Congo, where both climate and anthropogenic threats are expected to increase sharply by 2085. These results constitute key quantitative benchmarks for scientists and policymakers to shape transnational conservation and management strategies that aim to provide a sustainable future for central African forests. A large dataset of 6 million trees from 193 taxa is used to map the floristic and functional composition of central African forests and predict their vulnerability to climate change.

1. Overyielding in mixed-species forests has been demonstrated in a vast body of literature, and the focus of functional biodiversity research is now shifting towards a mechanistic understanding of these observations. 2. We explored diversity-productivity relationships at two sites of a large-scale tree diversity experiment, with harsh (Ged) and benign (Zed) environmental conditions for plantation establishment. Additive partitioning methodologies were adopted to detect phenomenological patterns in the productivity data, and the trait structure of mixed communities was used to advance insights into compositional effects. 3. After 6 years of plantation development, biomass productivity was significantly higher in mixtures compared to the monocultures of component species. We observed that processes operated through direct tree—tree interactions, as the diversity signal disappeared where trees in mixed stands were surrounded by conspecific neighbours only. This result is particularly relevant for mixed-species plantation systems, as trees are commonly planted in monospecific patches to simplify management. Partitioning unveiled strong selection effects at both plantation sites. However, at the harsh Ged-site this was caused by competitive dominance of species with fast young growth, whereas at the benign Zed-site, species with slow young growth improved their performances but not at the expense of others (i.e. trait-dependent complementarity). Species tolerance to shading is an influential trait for predicting biodiversity effects, with community-weighted means in shade tolerance mediating dominance effects (Ged) and functional diversity in shade tolerance mediating (trait-dependent) complementarity effects (Zed). 4. Synthesis. This study highlights that biodiversity effects in young tree plantations could be explained by the functional composition of mixed communities, with a key role for species levels of shade tolerance. As contrasting results between plantation sites were observed, future research should target the context-dependency of diversity-productivity relationships.

The longan industry produces a large amount of byproducts such as pericarp and seed, resulting in environmental pollution and resource wastage. The present study was performed to systematically evaluate functional components, i.e., polyphenols (phenolics and flavonoids) and alkaloids, in longan byproducts and their bioactivities, including antioxidant activities, nitrite scavenging activities in simulated gastric fluid and anti-hyperglycemic activities in vitro. Total phenolic and total flavonoid contents in pericarp were slightly higher than those in seeds, but seeds possessed higher alkaloid content than pericarp. Four polyphenolic substances, i.e., gallic acid, ethyl gallate, corilagin and ellagic acid, were identified and quantified using high-performance liquid chromatography. Among these polyphenolic components, corilagin was the major one in both pericarp and seed. Alkaloid extract in seed showed the highest DPPH radical scavenging activity and oxygen radical absorbance capacity. Nitrite scavenging activities were improved with extract concentration and reaction time increasing. Flavonoids in seed and alkaloids in pericarp had potential to be developed as anti-hyperglycemic agents. The research result was a good reference for exploring longan byproducts into various valuable health-care products.

Molybdenum-doped barium titanate (BaTiO 3 ) nanostructures were fabricated by a solid-state reaction and evaluated for simultaneous enhancement of dielectric and optical performance. X-ray diffraction confirmed that progressively higher Mo content drives a tetragonal to cubic phase transformation, evidencing effective lattice tuning. Complementary SEM and EDX analyses showed well-defined grain morphology and uniform elemental distribution, verifying successful Mo incorporation. XPS detected Mo in mixed valence states (Mo 3+ /Mo 4+ /Mo 6+ ) together with Ti 3+ species, implicating abundant oxygen vacancies that promote charge transport and surface reactivity. Dielectric measurements revealed a marked rise in room-temperature permittivity accompanied by lower loss, indicating improved polarization dynamics. UV–vis diffuse-reflectance spectra displayed a red-shifted absorption edge and a band-gap narrowing from 3.24 eV (pristine BaTiO 3 ) to 2.92 eV (MBT4), thereby extending visible-light harvesting. All Mo-doped BaTiO 3 samples exhibited notable visible-light photocatalytic performance, with the 3% Mo-doped sample (MBT3) achieving significantly enhanced degradation of Congo red dye under direct sunlight. Notably, MBT3 demonstrated about 90% degradation efficiency within 60 min, compared to the slower response of undoped BaTiO 3 , and the corresponding photocatalytic rate constant increased from 0.01754 min −1 (pure BTO) to 0.03673 min −1 , underscoring the superior reactivity and light-harvesting capability imparted by Mo incorporation. These results demonstrate that Mo incorporation simultaneously tailors BaTiO 3 crystal structure, electronic structure, and dielectric response, positioning the material as a promising multifunctional candidate for sustainable energy and environmental applications.

Community weighted mean trait, i.e., functional composition, has been extensively used for upscaling of individual traits to the community functional attributes and ecosystem functioning in recent years. Yet, the importance of intraspecific trait variation relative to species turnover in determining changes in CWM still remains unclear, especially under nutrient enrichment scenarios. In this study, we conducted a global data synthesis analysis and three nutrient addition experiments in two sites of alpine grassland to reveal the extent to which species turnover and ITV contribute to shift in CWM in response to nutrient enrichment. The results consistently show that the importance of ITV relative to species turnover in regulating CWM in response to nutrient enrichment strongly depends on trait attributes rather than on environmental factors (fertilization type, climatic factors, soil properties, and light transmittance). For whole plant traits (height) and leaf morphological traits, species turnover is generally more important than ITV in determining CWM following most treatments of nutrient addition. However, for leaf nutrient traits, ITV outweighed species turnover in determining shifts in CWM in response to almost all treatments of nutrient addition, regardless of types and gradients of the nutrient addition. Thus, our study not only provides robust evidence for trait-dependent importance of ITV in mediating community functional composition, but also highlights the need to consider the nature of functional traits in linking ITV to community assembly and ecosystem functioning under global nutrient enrichment scenarios.

1. 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. 2. 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. 3. 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. 4. 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 equivalents 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. 5. 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, grassdominated 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).