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Temperature and nutrients are known as crucial drivers for the variations of bacterial community structure and functions in oceans and lakes. However, their significance and mechanisms in influencing the bacterial community structure and function in mountain stream remain unclear. In this study, we investigated the spatiotemporal patterns of the bacterial communities and the main environmental factors in the Taizicheng River, a high-latitude mountainous stream, to reveal the main driving factors for sedimental bacterial communities. Our findings identified that the phyla Acidobacteriota and Bacteroidota served as the strong discriminant for sedimental bacterial community in the non-freezing and freezing periods, respectively. In contrast, no significant difference was detected in bacterial functional composition. Mantel test and Redundancy analysis showed that temperature and nutrients played significant roles in determining the bacterial community structure and temperature critically influenced the bacterial metabolic processes. The results of partial least squares path model demonstrated that temperature affected the bacterial community structure in both directly (43.70%) and indirectly pathways (41.10%) by affecting the sediment parameters. However, the functional composition was not significantly affected by temperature and nutrients. Our results highlight that the change of temperature can significantly alters the structure of bacterial communities rather than functional composition and provides new insights into the response mechanisms of bacterial communities to environmental factors which contributes to the deep understanding of the driving factors as well as the protection strategies for microbial communities in mountain stream and aquatic ecosystem. [ABSTRACT FROM AUTHOR]

The expansion of urban areas has led to land-use changes that affect aquatic biodiversity and ecosystem processes through several ways, such as increased runoff, water pollution, habitat homogenization, and disturbance of the natural flow. It is well known that urbanization induces profound changes in freshwater macroinvertebrate communities, but relatively few studies have approached this topic using trait-based methods. This severely limits our ability to monitor and predict potential alterations of ecosystem processes. We here provide empirical evidence about the effects of urbanization-related changes on the trait composition and functional diversity of freshwater macroinvertebrates from Patagonia (Argentina). Macroinvertebrate sampling and environmental characterization were carried out in 13 study sites distributed across three water courses in the Futaleufú river basin. We found changes in environmental conditions over the urban impact gradient, in turn accompanied by variation in functional diversity and trait composition of aquatic macroinvertebrates. Specifically, we detected lower functional diversity in urban and post-urban reaches, mainly attributed to shifts in the distribution of taxa within the functional space, rather to the extirpation of functionally distinct taxa located at the edges of it (i.e., functional evenness and dispersion decreased, but functional richness remained constant). We also found signs of functional homogenization at the most impaired sites, where gatherers and tegument-breathing taxa dominated. These changes were mainly explained by conductivity, biological oxygen demand, and oxygen levels in the water column. [ABSTRACT FROM AUTHOR]

One of the ways to evaluate the success of restoration strategies in degraded areas, in terms of restoring pollination, key process for the reproduction of most angiosperm species, is evaluating species traits, how they respond to changes in the environment and influence their interacting partners. In this study we asked: (i) does the phenological variation, the restoration strategy and the restoration age influence species richness, abundance, species composition and distribution of traits of bees and plants? (ii) do functionally similar species tend to interact with the same mutualistic partners? (iii) what are the most important traits that explain the similarity of interacting partners? We analyzed bee and plant communities in restored areas in the Atlantic Forest. We found that bee richness and abundance did not vary, and plant richness varied temporally. Bee and plant composition changed over time and among restoration strategies. Plant composition also varied with the restoration age. Functional composition, especially of bees, varied little among the tested factors. We also found that species with similar traits tended to interact with similar partners, and bee size, proboscis length and nesting sites were the most important traits to explain the interactions, while for plants, the most important traits were form of life, corolla color and shape. Our study demonstrated that interactions between bees and plants can be mediated by plant phenology and, considering that plant traits filter pollinators' traits, the choice of plant traits in restoration areas is fundamental for interactions. [ABSTRACT FROM AUTHOR]

Aim: Patterns of beta diversity reflect the formation dynamics of ecological communities. Here, we integrated geographic, phylogenetic, and phenotypic information of coastal woody vegetation to investigate (1) whether the observed dissimilarity between assemblages differs from that expected by chance, examining the roles of spatial and deterministic processes; (2) the relative contribution of beta‐diversity components (turnover and nestedness) for taxonomic, phylogenetic, and functional beta diversity; and (3) what environmental factors drive the differences in composition between assemblages for all these dimensions. Location: Brazil. Taxon: Angiosperm trees. Methods: We built dissimilarity matrices and partitioned the taxonomic, phylogenetic, and functional beta diversity from an incidence matrix, a phylogeny including the region's plants, and a matrix expressing functional distances. Using linear regressions, we tested the effects of different environmental predictors representative of the effects of water availability, thermal energy, habitat heterogeneity, edaphic constraints, climatic stability, and human influence on beta‐diversity patterns. Results: Taxonomic, phylogenetic, and functional dissimilarities exhibited a typical pattern of greater dissimilarity with distance (i.e., as expected by chance). However, these patterns showed different contributions of beta‐diversity components, predominating turnover in taxonomic and phylogenetic dissimilarity, and nestedness in functional dissimilarity. Water availability had a slight effect on patterns of taxonomic and phylogenetic dissimilarities. Main conclusions: The Brazilian coastal woody vegetation appears to have emerged through a dynamic of colonisation of evolutionarily distinct but functionally similar lineages that originated from adjacent phytogeographic domains, proportional to their diversity. This is consistent with a combination of both neutral and non‐neutral processes. Our findings underscore the complementary roles of different dimensions of beta diversity in explaining the dynamics of these vegetation communities. [ABSTRACT FROM AUTHOR]

Quantifying assemblage variation across environmental gradients provides insight into the ecological and evolutionary mechanisms that differentiate assemblages locally within a larger climate regime. We assessed how vascular plant functional composition and diversity varied across microenvironment to identify ecological differences in assemblages in a mountainous fieldsite in northeastern Utah, USA. Then, we looked at how life‐history strategies and information about phylogenetic differences affect the relationship between functional metrics and environment. We found less functionally dispersed assemblages that were shorter and more resource‐conservative on south‐facing slopes where intra‐annual soil temperature was hotter and more variable. In contrast, we found more functionally dispersed assemblages, that were taller and more resource‐acquisitive on north‐facing slopes where intra‐annual temperature was cooler and less variable. Herbaceous and woody perennials drove these trends. Additionally, including information about phylogenetic differences in a dispersion metric indicated that phylogeny accounts for traits we did not measure. At this fieldsite, soil temperature acts as an environmental filter across aspect. If soil temperature increases and becomes more variable, intra‐annually, the function of north‐ versus south‐facing assemblages may be at risk for contrasting reasons. On south‐facing slopes, assemblages may not have the variance in functional diversity needed to respond to more intense, stressful conditions. Conversely, assemblages on north‐facing slopes may not have the resource‐conservative strategies needed to persist if temperatures become hotter and more variable intra‐annually. Given these results, we advocate for the inclusion of aspect differentiation in studies seeking to understand species and assemblage shifts in response to changing climate conditions. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Questions: In the alpine region of the Himalaya, shrubs play a vital role in maintaining the diversity and functional composition of associated herbaceous communities through competition–facilitation interactions under varying environmental stress conditions. In this study, we specified the following questions: (1) what is the mode of interaction between dominant shrubs and the associated herbaceous communities; (2) how do differences in resource availability between contrasting microhabitats mediate interactions between shrub and herbaceous communities; and (3) how do dominant shrubs influence the functional composition of herbaceous communities under the canopy as compared to ones in the open? Study area: An alpine region of the western Himalaya, in India (32.24–33.15° N, 76.51–78.13° E). Methods: Field studies were conducted to evaluate the canopy effects of alpine shrubs such as Caragana versicolor, Juniperus polycarpos and Rhododendron anthopogon on species richness, abundance and functional composition of coexisting herbaceous communities. Results: The dominant alpine shrubs of the western Himalaya exert competitive interactions with associated herbaceous communities and have low species richness and abundance under their canopies compared to open habitats. Further, contrary to expectations, competitive interactions were more prominent at higher elevations than at lower ones, especially for J. polycarpos and C. versicolor. Although the shrub undercanopies possessed richer soil nutrient pools, this did not contribute toward the facilitation of herbaceous species under the canopies. Moreover, herbaceous species under the canopies were found to exhibit resource‐acquisitive functional strategies, whereas those in the open were resource‐conservative. Conclusions: The interaction between dominant alpine shrubs and the herbaceous community of the western Himalaya is competitive in nature, which influences species and functional composition and reorganizes herbaceous community assembly. Moreover, under future climate change scenarios the dominance of these shrubs will favour those herbaceous species that possess more competitive and resource‐acquisitive functional strategies. [ABSTRACT FROM AUTHOR]

Natural regeneration after mining activities depends largely on the soil seed bank (SSB) and aboveground vegetation (AGV) richness and composition. We evaluated the species diversity pattern of the SSB and AGV on soil and technosol across second‐growth Atlantic Forests (SGFs) after mining tailings deposition in Mariana, southeastern Brazil. Two second‐growth Atlantic seasonal semideciduous forests of different stand ages were selected: a 3‐year‐old stand of SGF re‐growing on tailings (SGF tailings) and a 30‐year‐old stand of native reference forest not affected by tailings (SGF nontailings). Overall, the results showed significant differences in forest attributes (species richness and composition) in the SSB and AGV between the two forest patches evaluated (SGF tailings and SGF nontailings). Moreover, both nonzoochoric and zoochoric dispersed species of AGV showed significant differences between second‐growth forests, with higher variability of community‐weighted mean in SGF tailings. The result shows smaller differences in species richness between forest types for both SBB (ranging 85 and 90 species) and AGV (~55 species). Despite the time difference between the secondary forest and the absence of zoochoric species in the tailings seed bank, the AGV that are re‐growing on mining tailings presented a high proportion of zoochoric species. This pattern of species richness and community composition variability observed in the technosol seed bank, and AGV that are re‐growing after the deposition of mining tailings are important recovery indicators for plant communities affected. [ABSTRACT FROM AUTHOR]

Copyright of Caldasia is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Bioflocs are microbial aggregates that play a pivotal role in shaping animal health, gut microbiota, and water quality in biofloc technology (BFT)-based aquaculture systems. Despite the worldwide application of BFT in aquaculture industries, our comprehension of the community composition and functional potential of the floc-associated microbiota (FAB community; ≥3 µm size fractions) remains rudimentary. Here, we utilized genome-centric metagenomic approach to investigate the FAB community in shrimp aquaculture systems, resulting in the reconstruction of 520 metagenome-assembled genomes (MAGs) spanning both bacterial and archaeal domains. Taxonomic analysis identified Pseudomonadota and Bacteroidota as core community members, with approximately 93% of recovered MAGs unclassified at the species level, indicating a large uncharacterized phylogenetic diversity hidden in the FAB community. Functional annotation of these MAGs unveiled their complex carbohydrate-degrading potential and involvement in carbon, nitrogen, and sulfur metabolisms. Specifically, genomic evidence supported ammonium assimilation, autotrophic nitrification, denitrification, dissimilatory nitrate reduction to ammonia, thiosulfate oxidation, and sulfide oxidation pathways, suggesting the FAB community’s versatility for both aerobic and anaerobic metabolisms. Conversely, genes associated with heterotrophic nitrification, anaerobic ammonium oxidation, assimilatory nitrate reduction, and sulfate reduction were undetected. Members of Rhodobacteraceae emerged as the most abundant and metabolically versatile taxa in this intriguing community. Our MAGs compendium is expected to expand the available genome collection from such underexplored aquaculture environments. By elucidating the microbial community structure and metabolic capabilities, this study provides valuable insights into the key biogeochemical processes occurring in biofloc aquacultures and the major microbial contributors driving these processes.IMPORTANCEBiofloc technology has emerged as a sustainable aquaculture approach, utilizing microbial aggregates (bioflocs) to improve water quality and animal health. However, the specific microbial taxa within this intriguing community responsible for these benefits are largely unknown. Compounding this challenge, many bacterial taxa resist laboratory cultivation, hindering taxonomic and genomic analyses. To address these gaps, we employed metagenomic binning approach to recover over 500 microbial genomes from floc-associated microbiota of biofloc aquaculture systems operating in South Korea and China. Through taxonomic and genomic analyses, we deciphered the functional gene content of diverse microbial taxa, shedding light on their potential roles in key biogeochemical processes like nitrogen and sulfur metabolisms. Notably, our findings underscore the taxa-specific contributions of microbes in aquaculture environments, particularly in complex carbon degradation and the removal of toxic substances like ammonia, nitrate, and sulfide.

Selective logging can impact tree composition and the long-term sustainability of forests. Studying the ecological consequences of logging practices is crucial for guiding forest management strategies aiming at maintaining ecological integrity and supporting landscape-level conservation goals. We investigated the consequences of very low-intensity selective logging in multiple tree life stages across a logged forest chronosequence in Gabon. We found that species composition differed between logged and unlogged forests at all life stages (seedlings, saplings, and adults), which were most pronounced in the understory of older forests (logged 10 years prior) compared to unlogged areas. However, logging explained a small portion of the variation in species composition (

Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Questions: We assessed interactions between climate change, bedrock types and snow cover duration on the trajectories of taxonomic and functional composition of subalpine plant communities. We predict (i) an increase in species richness on siliceous bedrock due to a reduced competition and a decrease in richness on calcareous bedrock due to increasing drought stress; (ii) decreasing snow cover duration should induce a higher shrub encroachment in hollows as compared to ridges; and (iii) increasing growing season temperature should induce taller sizes and more conservative growth traits, in particular in hollows. Location: Subalpine belt of the Grandes Rousses mountain range, southwestern Alps (France). Methods: 189 vegetation plots were sampled in 1997 and 2017–2018. The duration of snow cover was assessed during two years in 1995–1997 and five functional traits were measured on 108 species in 2021. We performed multivariate analyses, quantified community‐weighted means (CWM) of traits and used ANOVAs to detect responses to local‐scale factors and changes in snow cover, temperature and precipitation since 1997 according to a nearby meteorological station. Results: Overall, taxonomic composition weakly changed and changes were more dependent on the position of communities along the snow cover duration gradient than on their bedrock type. The abundance of drought‐tolerant species increased at the border of hollows and there was, over all communities, a slight increase in the abundance of dwarf shrubs and tall herbaceous species, a strong decrease in short herbaceous species and, thus, an overall decrease in species richness. There were important overall changes in CWM of size traits, in particular leaf area which increased the most in hollows irrespective of bedrock types. Conclusion: In this subalpine site the effects of decreasing snow cover duration overwhelmed the effects of bedrocks, which may explain the overall increase in competitive species and decrease in species richness. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The gut microbiota of aquaculture species contributes to their food metabolism and regulates their health, which has been shown to vary during aquaculture progression of their hosts. However, limited research has examined the outcomes and mechanisms of these changes in the gut microbiota of hosts. Here, Kuruma shrimps from the beginning, middle, and late stages of aquaculture progression (about a time duration of 2 months between each stage) were collected and variations in the gut microbiota of Kuruma shrimp during the whole aquaculture process were examined. High-throughput sequencing demonstrated increases in the diversity and richness of the shrimp gut microbiota with aquaculture progression. In addition, the gut microbiota composition differed among cultural stages, with enrichment of Firmicutes, RF39, and Megamonas and a reduction in Proteobacteria in the mid-stage. Notably, only very few taxa were persistent in the shrimp gut microbiota during the whole aquaculture progression, while the number of taxa that specific to the end of aquaculture was high. Network analysis revealed increasing complexity of the shrimp gut microbiota during aquaculture progression. Moreover, the shrimp gut microbiota became significantly more stable towards the end of aquaculture. According to the results of neutral community model, contribution of stochastic processes for shaping the shrimp gut microbiota was elevated along the aquaculture progression. This study showed substantial variations in shrimp gut microbiota during aquaculture progression and explored the underlying mechanisms regulating these changes. [ABSTRACT FROM AUTHOR]

NMR spectroscopy is one of the effective methods for the study of plant raw materials, which makes it possible to identify differences in the structure and functional composition of lignins of various types of plant biomass. However, there are a number of limitations in the use of this method – in particular, the registration of NMR spectra at some nuclei (13C, 31P, etc.) usually requires considerable amount of time. This article proposes an approach to reduce the recording time of 31P NMR spectra by a factor of 17 without losing the quality of the result. With the help of this method and with the use of optimized experimental parameters, the functional group analysis of lignins of some softwood and hardwood species and herbaceous plants distributed in the European North of the Russian Federation was carried out. The types of structural units and their characteristic interstructural relationships per 100 phenylpropane units were determined by HSQC NMR. Differences in the functional composition and features of the structural organization of lignins were identified depending on the family to which the plant belongs. On the basis of the obtained array of experimental data the strategies of processing of specific types of plant raw materials were proposed. For example, lignins of the Birch and Beech families showed the largest number of β-aryl ether fragments with a free hydroxyl group in the α-position, which indicates the greater reactivity of these lignins. Accordingly, representatives of these families are priority raw materials in the development of lignin processing methods. At the same time, the structure of lignins of representatives of the Beech family proved to be the most resistant to hydrolytic degradation, which is important for lignin-directed bioprocessing concepts. Acknowledgments: This study was funded by the Russian Science Foundation (Grant project no. 22-13-20015). The work of Yuliya A. Sypalova was supported by the RFBR Grant for Postgraduate Students (Project no. 20-33-90126). The equipment of the Core Facility Center “Arktika” of the Northern (Arctic) Federal University named after M.V. Lomonosov was used. For citation: Sypalova Yu.A., Shestakov S.L., Kozhevnikov A.Yu. Functional Composition and Structural Features of Higher Plant Lignins. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 5, pp. 164–183. (In Russ.). https://doi.org/10.37482/0536-1036-2023-5-164-183

Questions: Our study aims to understand whether priority effects or environmental filters drive community assembly in 20‐year‐old restoration areas in the Brazilian Atlantic Forest. For this, we investigated the following questions: (i) does the initial composition of planted communities (distinct combination of ecological groups) affect the natural regeneration regarding functional composition (mean trait values), diversity (functional and taxonomic), and vegetation structure? (ii) Which functional traits of the planted community have the potential to promote or constrain natural regeneration? Location: The study was carried out in the Poço das Antas Biological Reserve, located in Rio de Janeiro state, Brazil, in a stand of 2.16 hectares with an experimental restoration design established in the year 2000 to test tree species performance of different ecological groups. Methods: In 2020, we sampled trees with a diameter at breast height greater than 2.5 cm in 20 m × 20 m plots with four replicates per treatment and measured leaf, wood, and seed functional traits. Then, we estimated the diversity (functional and taxonomic richness), functional composition, and vegetation structure of natural regeneration, compared them between treatments, and tested which traits of the planted community influenced them. Results: Natural regeneration exhibited significant differences between treatments, particularly regarding the diversity dimension (functional and taxonomic) and vegetation structure (basal area and abundance). Wood density, leaf phosphorus content, and leaf C:N ratio of the planted species were associated with natural regeneration (functional composition, diversity, and vegetation structure). Conclusions: Priority effects in conservative tree planting communities affect natural regeneration, while functional convergence observed in acquisitive planting communities suggests the role of environmental filtering. Communities with low wood density, low C:N ratio, and high specific leaf area, which characterize an acquisitive resource‐use strategy, exhibited higher functional and taxonomic diversity of natural regeneration, leading to the desired trajectory in ecological restoration. [ABSTRACT FROM AUTHOR]

Along with worldwide urbanization, upheavals in habitat and temperature are major threats for biodiversity. However, due to their interdependence, their relative roles as drivers of animal community composition remain entangled. Here, we investigated how taxonomic and functional compositions of arthropod communities were related to uncorrelated habitat and temperature gradients, and compared landscape (i.e., urbanization, Urban Heat Island (UHI)) to local variables (i.e., vegetation height and cover, near-ground temperature). We sampled 20,499 spiders (137 species) on 36 grasslands in Rennes (northwestern France). Unlike rural areas, urban sites were characterized by short vegetation and intense UHI, hosted species-poor communities, and were composed of small thermophilic species. UHI intensification and local loss of habitat complexity (short and dense vegetation) were associated with declining large and heat-sensitive species. These results highlight the prevalent role of urban warming, rather than land cover change, as an urban filter. Further, we show that landscape-scale UHI, not local temperature, filters species according to their functional attributes. UHI can therefore be considered as a thermal barrier, filtering species according to their physiological capacity to cope with urban thermal conditions. Finally, to counterbalance biotic homogenization, we argue for the importance of implementing complex habitat structures at the local scale within urban green infrastructure. [ABSTRACT FROM AUTHOR]

Ecological restoration is critical for recovering degraded ecosystems but is challenged by variable success and low predictability. Understanding which outcomes are more predictable and less variable following restoration can improve restoration effectiveness. Recent theory asserts that the predictability of outcomes would follow an order from most to least predictable from coarse to fine community properties (physical structure > taxonomic diversity > functional composition > taxonomic composition) and that predictability would increase with more severe environmental conditions constraining species establishment. We tested this "hierarchy of predictability" hypothesis by synthesizing outcomes along an aridity gradient with 11 grassland restoration projects across the United States. We used 1829 vegetation monitoring plots from 227 restoration treatments, spread across 52 sites. We fit generalized linear mixed‐effects models to predict six indicators of restoration outcomes as a function of restoration characteristics (i.e., seed mixes, disturbance, management actions, time since restoration) and used variance explained by models and model residuals as proxies for restoration predictability. We did not find consistent support for our hypotheses. Physical structure was among the most predictable outcomes when the response variable was relative abundance of grasses, but unpredictable for total canopy cover. Similarly, one dimension of taxonomic composition related to species identities was unpredictable, but another dimension of taxonomic composition indicating whether exotic or native species dominated the community was highly predictable. Taxonomic diversity (i.e., species richness) and functional composition (i.e., mean trait values) were intermittently predictable. Predictability also did not increase consistently with aridity. The dimension of taxonomic composition related to the identity of species in restored communities was more predictable (i.e., smaller residuals) in more arid sites, but functional composition was less predictable (i.e., larger residuals), and other outcomes showed no significant trend. Restoration outcomes were most predictable when they related to variation in dominant species, while those responding to rare species were harder to predict, indicating a potential role of scale in restoration predictability. Overall, our results highlight additional factors that might influence restoration predictability and add support to the importance of continuous monitoring and active management beyond one‐time seed addition for successful grassland restoration in the United States. [ABSTRACT FROM AUTHOR]

The quantification of plant diversity–productivity relationships is essential for accurate productivity assessments. Global change drivers are altering resource availability and biodiversity. However, the extent to which multiple attributes of diversity (species, functions) buffer community productivity in response to the resource availability changes and the potential driver mechanisms of the diversity‐productivity relationship still needs to be the consensus. We investigated the ephemeral plant diversity–productivity relationships of different attributes along a precipitation gradient in the Gurbantunggut Desert, China. To evaluate the potential mechanisms by which diversity and functional composition affect aboveground productivity (niche complementarity and selection effect). Our results showed that (1) the variance of species richness (SR), Rao's quadratic entropy (RaoQ), community‐weighted mean of height (CWMH), and community‐weighted mean of leaf phosphorus concentration (CWMP) was larger among sites (variation between different sites) than subplots (variation between different subplots). Among subplots, the variance of community‐weighted mean of specific leaf area (CWMSLA), community‐weighted mean of leaf carbon concentration (CWMC), and community‐weighted mean of leaf nitrogen concentration (CWMN) was larger than the sites. (2) SR, RaoQ, CWMC, CWMN, CWMH, pH, and mean annual precipitation (MAP) collectively influenced the accumulation of aboveground biomass (AGB). (3) Species diversity and MAP have strongly affected AGB and accounted for 50% and 42%. The study confirms that SR is the optimal predictor of biomass in ephemeral plants. Complementation effects may be the primary mechanism explaining the relationship between biodiversity and productivity in the Gurbantunggut Desert, and thus the effect of plant diversity cannot be downplayed. [ABSTRACT FROM AUTHOR]

Excessive use of the eyes, the environment is too dry or interfered by other factors, it is easy to cause the eyes to adjust the refraction for a long time, causing visual fatigue, which is mainly manifested as: Frequent blurred vision, eye soreness, dryness, tears and other eye discomfort. Studies have shown that supplementing appropriate substances can help relieve visual fatigue. At present, research on visual fatigue and eye health has made some progress, but lack of systematic summary. Therefore, this paper reviews the physiological mechanism of visual fatigue. Using the national special food information query platform as a data retrieval tool, the raw materials and iconic components of health foods that have been approved to alleviate visual fatigue are systematically counted, classified and analyzed. The progress of functional components with the function of relieving visual fatigue is systematically reviewed in order to provide some reference and inspiration for the development of health foods to alleviate visual fatigue.

The analysis of plant trait composition has raised significant interest among freshwater ecologists as a complementary approach for assessing the effects of environmental change on ecosystem functions. In this study, we investigated patterns of functional traits of the aquatic macrophyte assemblages of 74 lotic ecosystems of Greece, and we identified associations between species traits and environmental variables (hydromorphological and physicochemical parameters) through testing the hypothesis that the environmental features determine the spatial structure of traits. We allocated 12 traits to a total of 39 hydrophyte species, and we conducted RLQ and fourth corner analysis to explore relationships between species, trait composition, and environmental gradients. Based on the results of the RLQ, a hierarchical cluster analysis was conducted to identify groups of plants that share common trait characteristics. Plants were discriminated into five discrete groups based mostly on their life form (e.g., free-floating, rooted submerged etc.) and their ecological preference for nitrogen levels. Hydromorphological parameters had a higher contribution than physicochemical variables in explaining the total variance of the trait data, with water abstraction, channel substrate, and hydrologic alteration being the most important. Our analysis did not reveal significant bivariate relationships between single traits and environmental parameters, although the five groups of macrophyte assemblages appeared to associate with certain environmental gradients. Free-floating and emergent plants were related to higher concentrations of nutrients, whereas rooted submerged plants were related to higher oxygen concentration and increased pH. In addition, free-floating plants were highly associated with metrics of hydromorphological change. Our findings showed clear discrimination of macrophytes based on their functional composition and association of traits with environmental gradients. Thus, further research could explore whether macrophyte functional groups can serve as indicators of environmental change and the overall ecosystem health. [ABSTRACT FROM AUTHOR]

Upscaling trait‐based restoration to regional levels is necessary as we enter the UN Decade on Ecosystem Restoration. For this, we need to select species that achieve functional targets considering the regional species pool.Here, we present a framework to achieve multiple restoration targets using a regional species pool containing the species available on the market, species unavailable, and species that occur in reference ecosystems. The framework enables optimising functional diversity (FD), recovering FD and composition using reference ecosystems, reducing cost and increasing species diversity in restoration. Additionally, our framework allows the detection of functionally relevant species in the regional pool that are unavailable for restoration on the market. We illustrate our framework with a data set of Brazilian savanna tree communities.It was not possible to optimise FD with the species available on the market. To achieve this target, it would be necessary to use unavailable species from the regional pool. However, with the species available on the market it was possible to obtain communities resistant to fire and to restore functional composition and diversity to levels similar to or greater than those observed in reference ecosystems.Synthesis and applications. Our framework selects species to achieve multiple targets in large‐scale trait‐based restoration initiatives. The framework shows a range of solutions that can be achieved with the regional species pool. That allows the restoration practitioner to verify if functional parameters are truly optimised and which species should be added to the market or collected from the wild to achieve restoration targets. It also shows how different selected communities are from reference ecosystems, avoiding the unintentional creation of novel ecosystems. [ABSTRACT FROM AUTHOR]

High invasiveness and well-documented negative impact on biodiversity and ecosystem functioning make Solidago canadensis L. a species of global concern. Despite a good understanding of the driving factors of its invasions, it remains unclear how the surrounding landscape may shape invasion success of this species in human-transformed ecosystems. In our study, we investigated the impacts of different landscape features in the proximity of early successional wastelands on S. canadensis biomass allocation patterns. Further, we examined the relationships between the surrounding landscape, S. canadensis cover, and plant functional diversity, used as a supportive approach for the explanation of mechanisms underlying successful S. canadensis invasion. We found that increasing river net length had positive impacts on S. canadensis rhizome, stem, and total above ground biomass, but negative effects on leaf biomass, indicating that vegetative spread may perform the dominant role in shaping the competitiveness of this invader in riverine landscapes. A higher proportion of arable lands positively influenced S. canadensis above ground and flower biomass; thus promoting S. canadensis invasion in agricultural landscapes with the prominent role of habitat filtering in shaping vegetation structure. Concerning an increasing proportion of settlements, flower biomass was higher and leaf biomass was lower, thereby influencing S. canadensis reproductive potential, maximizing the odds for survival, and indicating high adaptability to exist in an urban landscape. We demonstrated high context-dependency of relationships between functional diversity components and surrounding landscape, strongly influenced by S. canadensis cover, while the effects of surrounding landscape composition per se were of lower importance. Investigating the relationships between the surrounding landscape, invasive species performance, and plant functional diversity, may constitute a powerful tool for the monitoring, controlling, and predicting of invasion progress, as well as the assessment of ecosystem invasibility. [ABSTRACT FROM AUTHOR]

Soil microbial communities have an important role in plant establishment and health. Particularly, the role of the soil microbiome in agriculture is of current interest. The study of microbial communities associated with purslane could open questions about the rational exploitation of the microbiota for sustainable agricultural purposes. In this study, the composition of the fungal and bacterial communities and the bacterial metabolic functions, associated with the rhizospheres of two purslane genotypes (one commercially available and one collected from the wild in Spain) were evaluated. The results showed a clear effect of purslane genotype on fungal and bacterial community composition and functional profiles. The bacterial community of the commercial purslane rhizosphere was characterized by more numerous metabolic pathways, mainly pathways related to Terpenoids and Polyketides, Carbohydrate, Lipid, and Amino Acid metabolism. By contrast, the rhizosphere bacterial community of the Spanish (wild) genotype was characterized by the enrichment of functions related to cellular processes such as cell motility and transport. We hypothesize that these differences could be due to differential effects of root exudate composition on the microbial functional community composition. This finding points out the need to consider differences in the functional characteristics of plant genotypes when selecting the beneficial microorganisms to be used as biofertilizers aiming to maximize plant growth and resistance to environmental stressors. [ABSTRACT FROM AUTHOR]

In an Afrotropical region experiencing massive deforestation, restoration approaches should provide sustainable solutions for recovering biodiversity. Arthropods are a sensitive taxonomic group for habitat alteration by deforestation and can be good indicators for restoration studies. Ground-dwelling arthropods provide important ecosystem functions, such as predation or organic matter decomposition, thereby contributing to ecosystem functionality. The consequences of post-mining management on arthropods in the Afrotropical region remain understudied. We carried out a comprehensive sampling of ground-dwelling arthropods in the dry and wet seasons across four land-use types in the semi-deciduous forest zone of Ghana. We then analysed whether the specific tree communities, vegetation structure and seasonal differences affected arthropod communities in the restored post-mining forest compared to the dominant alternative land-use type (agroforestry plantation), a natural reference (natural forest) or an unmanaged former mining area (gravel mine). In total, 43,364 arthropods were sampled and assigned to 78 taxonomic groups representing 14 order/sub-order, 28 beetle families, 25 spider families, 5 hunting guilds of spiders and 6 trophic groups of beetles. Overall, Araneae, Coleoptera, Hymenoptera and Orthoptera all had higher activity densities in the wet season. The vegetation structure of the three land-use types with trees supported a greater overall activity density of arthropods and a more diverse functional composition compared to the unmanaged gravel site. Pronounced variation between the dry and wet seasons further influenced the taxonomic and functional composition. The active forest restoration of this post-mining area is a promising approach to drive arthropod communities towards a comparable state observed in the natural forest. [ABSTRACT FROM AUTHOR]

A key step during industrial design is the passing of design information from computer aided design (CAD) to analysis tools (CAE) and vice versa. Here, one is faced with a severe incompatibility in geometry representation: While CAD is usually based on surface representations, analysis mostly relies on volumetric representations. The forward pass, i.e., converting CAD data to computational meshes, is well understood and established. However, the same does not hold for the inverse direction, i.e., CAD reconstruction of deformed geometries resulting from analysis. This is particularly important for industrial workflows in which the shape optimization of an initial product is outsourced. Such shape optimization is the focus of this work. The few reconstruction methods reported mainly rely on spline fitting, in particular on creating new splines similar to shape reconstruction from 3D imaging. In contrast, this paper studies a novel approach that reuses the CAD data given in the initial design. We show that this concept enables one to shape reconstruct mediocre deformations while preserving the initial notion of features defined during design. Furthermore, reusing the initial CAD representation reduces the shape reconstruction problem to a shape modification problem. We study this unique feature and show that it enables the reconstruction of CAD data from computational meshes by composing each spline in the initial CAD data with a single, global deformation spline. While post-processing is needed for use in current CAD software, most notably, this novel approach enables reconstructing complete CAD models even from defeatured computational meshes. [ABSTRACT FROM AUTHOR]

Introduction: Soil fertility is a major determinant of plant-microbial interactions, thus, directly and indirectly affecting crop productivity and ecosystem functions. In this study, we analysed for the first time the effects of fertilizer addition on the cropping of purslane (Portulaca oleracea) with particular attention to the taxonomic and functional characteristics of their associated soil microbiota. Methods: We tested the effects of different doses of inorganic fertilization differing in the amount of N:P:K namely IT1 (300:100:100); IT2 (300:200:100); IT3 (300:200:200); and IT4 (600:100:100) (ppm N:P:K ratio) and organic fertilization (compost tea) which reached at the end of the assay the dose of 300 ppm N. Results and discussion: Purslane growth and soil quality parameters and their microbial community structure, abundance of fungal functional groups and prevailing bacterial metabolic functions were monitored. The application of compost tea and inorganic fertilizers significantly increased the purslane shoot biomass, and some soil chemical properties such as pH and soil enzymatic activities related to C, N and P biogeochemical cycles. The bacterial and fungal community compositions were significantly affected by the organic and chemical fertilizers input. The majority of inorganic fertilization treatments decreased the fungal and bacterial diversity as well as some predictive bacterial functional pathways. Conclusions: These findings suggest that the inorganic fertilization might lead to a change of microbial functioning. However, in order to get stronger evidence that supports the found pattern, longer time-frame experiments that ideally include sampling across different seasons are needed. Thus, further research is still needed to investigate the effects of fertilizations on purslane productivity under commercial field conditions. [ABSTRACT FROM AUTHOR]

Soil fungal community characteristics of alpine timberlines are unclear. In this study, soil fungal communities in five vegetation zones across timberlines on the south and north slopes of Sejila Mountain in Tibet, China were investigated. The results show that the alpha diversity of soil fungi was not different between the north- and south-facing timberlines or among the five vegetation zones. Archaeorhizomyces (Ascomycota) was a dominant genus at the south-facing timberline, whereas the ectomycorrhizal genus Russula (Basidiomycota) decreased with decreasing Abies georgei coverage and density at the north-facing timberline. Saprotrophic soil fungi were dominant, but their relative abundance changed little among the vegetation zones at the south timberline, whereas ectomycorrhizal fungi decreased with tree hosts at the north timberline. Soil fungal community characteristics were related to coverage and density, soil pH and ammonium nitrogen at the north timberline, whereas they had no associations with the vegetation and soil factors at the south timberline. In conclusion, timberline and A. georgei presence exerted apparent influences on the soil fungal community structure and function in this study. The findings may enhance our understanding of the distribution of soil fungal communities at the timberlines of Sejila Mountain. [ABSTRACT FROM AUTHOR]

Forest aboveground biomass (AGB) plays an important role in regulating the global carbon cycle and is thus an essential component of ecosystem functioning. In the relationships between biodiversity and ecosystem functioning (BEF), studies have shown that many biotic factors (e.g., species, functional traits, and large trees) and abiotic factors have significant impacts on AGB. However, the relative strength of these affecting factors remains unclear. In this study, we analyzed woody plants (diameter at breast height [DBH] ≥ 1 cm) within a 1.6 ha plot in an old-growth subtropical natural forest in southern China. We used structural equation models to test the effects of tree diversity (species, phylogenetic, functional, and size inequality), functional composition, large trees, and environmental factors (topography, soil nutrients, and understory light) on AGB. Our results indicated that size inequality, the community-weighted mean of maximum DBH (CWM_MDBH), and large trees had significant, positive effects on AGB (p < 0.001), while lower soil phosphorus content was found to promote an increase in AGB. Furthermore, large trees, which were mostly composed of dominant tree species, were the main driver of AGB, and the effect of functional composition (e.g., CWM_MDBH) on AGB was substantially reduced by large trees. We argue that the selection effect plays a key role in regulating BEF relationships in subtropical natural forests and conclude that retaining large-diameter trees and dominant species, along with sustaining a complex stand structure, are key measures for improving productivity. [ABSTRACT FROM AUTHOR]

Questions: Woody encroachment in savannas has been associated with changing taxonomic composition and ecosystem function. Interestingly, there is little understanding of how encroachment impacts plant functional diversity and how those changes relate to plant demography, a crucial mediator between taxonomic composition and ecosystem function. Location: Southeastern Brazil. Methods: Using a landscape scale fire suppression experiment in a diverse Brazilian savanna, we quantify how change in species composition over seven years impacted vegetative and reproductive tree functional diversity as determined by new recruits, dead and surviving trees. Results: Over seven years, tree above‐ground biomass increased by 15%, while total species richness did not change. Despite minor changes, species composition remained overall similar (82%), with few species contributing significantly to plot dissimilarity over time. There were small changes in vegetative traits, where the community‐weighted mean increased in maximum tree height (↑ 2.1%) and specific leaf area (↑ 5.3%), and decreased in wood density (↓ 1.3%) and bark thickness (↓ 9.4%). Changes in reproductive traits were larger than in vegetative traits, with an increase in the prevalence of monoecy (↑ 32.6%), dioecy (↑ 44.2%), large seeds (↑ 20.3%), animal‐mediated seed dispersal (↑ 4.9%) and pollination by very small insects (↑ 45.5%), and a decrease in the prevalence of hermaphroditism (↓ 9%), small seeds (6.8%) and pollination by small insects (12.5%). The overall decrease in bark thickness and increase in monoecy and dioecy were mainly driven by characters of the new recruits, while the overall increase in specific leaf area (SLA) and decrease in small seeds appeared largely determined by the loss of trees possessing those traits. Conclusions: Encroachment leads to changes that are likely increasing ecosystem vulnerability to fire and drought. Further, the compositional changes observed appear to drive marked change in reproductive traits, indicating increasing dependence on animals for dispersal and reproduction. Understanding post‐hoc encroachment impacts in an era of widespread pervasive encroachment is fundamental to reconciling ecosystem functions such as nutrient cycling and pollination services as there is a loss of species with open ecosystem life‐history strategies. Among savannas, there remains an urgent need to understand relationships between woody cover and ecosystem function to determine thresholds in woody cover promoting resilient savanna ecosystems. [ABSTRACT FROM AUTHOR]

The 'mass ratio' hypothesis states that ecosystem functioning is driven by the functional traits of the most dominant species in communities. Thus, we aimed to evaluate (i) How topographical conditions and stand age determine changes in tree community composition, richness, abundance and carbon dominant (CD) species, and (ii) Assess whether community-weighted mean of functional trait values of CD species explain aboveground carbon (AGC) stock. We used community-weighted mean of wood density and maximum stem diameter to evaluate the effect of functional dominance in AGC stock. We found that different topographic conditions and stand age change community composition, richness, abundance and CD species along the late-secondary stage. Our results showed that functional trait values of CD species determine AGC stock. Thus, the proportion of CD species was shaped by topography and stand age, whereas carbon stock by the dominant species' functional traits (wood density and diameter). This study advances our understanding of the mechanisms that drive carbon stock in tropical forests and supports the 'mass ratio' hypothesis. We emphasize the relevance of the trait-based approach to understand forest functioning and trait functional composition and taxonomic identity for carbon storage, recovery and increase in secondary Atlantic Forests. [ABSTRACT FROM AUTHOR]

Along with worldwide urbanization, upheavals in habitat and temperature are major threats for biodiversity. However, due to their interdependence, their relative roles as drivers of animal community composition remain entangled. Here, we investigated how taxonomic and functional compositions of arthropod communities were related to uncorrelated habitat and temperature gradients, and compared landscape (i.e., urbanization, Urban Heat Island (UHI)) to local variables (i.e., vegetation height and cover, near-ground temperature). We sampled 20,499 spiders (137 species) on 36 grasslands in Rennes (northwestern France). Unlike rural areas, urban sites were characterized by short vegetation and intense UHI, hosted species-poor communities, and were composed of small thermophilic species. UHI intensification and local loss of habitat complexity (short and dense vegetation) were associated with declining large and heat-sensitive species. These results highlight the prevalent role of urban warming, rather than land cover change, as an urban filter. Further, we show that landscape-scale UHI, not local temperature, filters species according to their functional attributes. UHI can therefore be considered as a thermal barrier, filtering species according to their physiological capacity to cope with urban thermal conditions. Finally, to counterbalance biotic homogenization, we argue for the importance of implementing complex habitat structures at the local scale within urban green infrastructure.

To sample bee communities, a combination of methods is necessary, the most common being hand netting (HN) and pan traps (PT). However, there has been little exploration into how vertical distribution of PT can improve their sampling efficiency, also taking the temporal variation of floral resources into account.Here, we analysed the properties of bee communities sampled with PT at different heights (1.6 and 4.0 m) compared with PTs close to the ground, HN and large blue bucket trap (BB). In addition, we tested the effect of variation in the availability of floral resources on the performance of each method. Bees were collected in fragments of the Brazilian Caatinga.We captured 60 bee species with PTs, HN and BB, with significant increases in the sample coverage with elevated bowls (BB = 56.7%, HN = 60.0%, PT0.3 m = 23.3%, PT1.6 m = 36.7%, PT4.0 m = 50.0%). Elevating the bowls increased the sampling of bees with larger body size. Considering the three heights, PTs registered similar richness compared to HN and BB, but differed in the composition of species and ecological traits.When floral resource availability was greater, the abundance and richness of bees caught in PTs decreased, however, the elevated PT increased their ecological uniqueness (degree of uniqueness of the samples in terms of community composition). Thus, elevating PTs enables the capture of bees that forage at a specific height when floral resources increase.Our results highlight the importance of the vertical distribution of PT for sampling bees, since it improves their performance and its complementarity with other methods. [ABSTRACT FROM AUTHOR]

Hunting impacts tropical vertebrate populations, causing declines of species that function as seed dispersers and predators, or that browse seedlings and saplings. Whether and how the resulting reductions in seed dispersal, seed predation, and browsing translate to changes in the tree composition is poorly understood. Here, we assess the effect of defaunation on the functional composition of communities of tree recruits in tropical rainforests in French Guiana. We selected eight sites along a gradient of defaunation, caused by differences in hunting pressure, in otherwise intact old‐growth forests in French Guiana. We measured shifts in functional composition by comparing leaf and fruit traits and wood density between tree recruits (up to 5 cm diameter at breast height) and adults, and tested whether and how these compositional shifts related to defaunation. We found a positive relationship with defaunation for shifts in specific leaf area, a negative relationship for shifts of leaf toughness and wood density, and a weak relationship for shifts in fruit traits. Our results suggest that the loss of vertebrates affects ecological processes such as seed dispersal and browsing, of which browsing remains understudied. Even though these changes sometimes seem minor, together they result in major shifts in forest composition. These changes have long‐term ramifications that may alter forest dynamics for generations. [ABSTRACT FROM AUTHOR]

Despite the growing number of dam removals, few have been studied to understand their impacts on stream fish communities. An even smaller proportion of dam removal studies focus on the impacts of low‐head dam removals, although they are the most common type of dam. Instead, the majority of removal studies focus on the impacts of larger dams. In this study, two previously impounded Illinois Rivers were monitored to assess the impacts of low‐head dam removal on the functional assemblage of stream fishes. Study sites were sampled each fall from 2012–2015 (pre‐dam removal) and 2018–2020 (post‐dam removal) in three locations: the tailrace, impoundment, and river channel. Fishes were aggregated into habitat and reproductive guilds, relating community changes to habitat, environmental metrics, and stream quality. Prior to removal, the slackwater guild was the most prevalent habitat guild throughout both rivers, while nest builders and benthic spawners were the most abundant reproductive guilds. During the two years following removal, fish assemblage throughout both rivers shifted to a more evenly distributed representation of habitat and reproductive guilds, while restoration of lotic habitat conditions increased, as surface water temperatures decreased and QHEI, IBI, and dissolved oxygen increased. This shift in environmental metrics and increase in overall stream quality increased, particularly in the formerly impounded reaches, indicate diminished habitat homogeneity, and a shift towards natural habitat diversity. This habitat diversification likely led to the restoration of a range of potential niches, thereby increasing the array of guild types inhabiting these rivers, while simultaneously preventing single‐guild dominance. [ABSTRACT FROM AUTHOR]

Forests play important role in hydrological processes such as evapotranspiration, infiltration, surface runoff, and distribution of precipitation waters. This study evaluates soil water repellency (SWR) in a mountain forest area of Slovakia (Central Europe). Findings of previous studies suggest that the variability of SWR is associated mainly with differences in soil moisture. On the other hand, the role of soil organic matter (SOM) quality in spatial and/or temporal WR changes is less clear, particularly at the plot scale. To measure SOM quality, we used Fourier-transform infrared (FTIR) spectroscopy and thermogravimetry (TG). It was found that FTIR data and the results of thermal analysis are linked to dissimilar wettability of the studied soils. WR samples contained more aliphatic structural units in comparison to wettable soils, which showed a higher relative amount of polar functional groups. Thermogravimetric data suggest that SOM in all 45 samples is relatively labile. This is in accordance with strongly acidic pH and high C/N ratio. The amount of SOM degraded at around 250 °C was significantly correlated with SWR data and at the same time with FTIR peak areas characteristic for aliphatic structural units. This suggests that the accumulation of raw (labile) OM, containing nonpolar functional groups, supports the susceptibility of soils to WR. A significant portion of the variability in WR data was explained by multiple regression analysis, using field water content, FTIR peak areas, and SOM thermal characteristics as predictors. The results confirmed that even the soils occurring in a relatively humid and cold climate may show considerable WR during summer. [ABSTRACT FROM AUTHOR]

The organization of species metacommunities can be controlled by local factors, such as habitat quality, landscape factors, such as land use, and spatial factors, such as stream network distances. Species within a metacommunity have different traits that may be used to understand the determinants of community structure. This study aimed to understand how changes in environmental and spatial factors affected stream fish assemblages delineated based on their dispersal-related traits, such as preferential habitat use (i.e., benthic, nektobenthic, nektonic, marginal, and surface), preference for water velocity (i.e., fast, intermediate, and slow), and body size (i.e., small, medium, and large). We sampled 18 stream reaches in a dendritic network in the Upper Paraná River basin, located in the Brazilian Cerrado biome. We used variation partitioning techniques to test the relative effects of local environmental, landscape, and spatial variables on different species groups defined according to dispersal-related traits. Environmental and spatial variables weakly explained the variation in total assemblage taxonomic composition. However, based on different functional trait groups, we found that the environment had a strong relationship with assemblage composition of nektobenthic and small fish, whereas spatial variables were most strongly associated with marginal and surface fish. Large-scale spatial variables were associated with large fish and those that prefer slow water, whereas fine-scale variables were associated with small and surface-dwelling fish. These findings help improve understanding of how functional composition of stream fish assemblages may be affected by urban development, riparian conversion, and resulting changes in local environmental conditions. [ABSTRACT FROM AUTHOR]

Increasing biodiversity in highly diverse plant communities can jointly increase ecosystem function and ecosystem vulnerability. This paradox requires further attention. This study analyzed the functional response of plant communities to above- and below-ground parameters along the chronosequence (degraded pastures (DP), early forests (EF), intermediate forests (IF), and old-growth forests (OF)) in two highly fragmented landscapes of the Colombian Amazon as an estimate of the level of functional vulnerability. Three sets of functional attributes were evaluated: (i) functional composition based on the community-weighted mean (CWM) of five traits; (ii) functional diversity based on the multi-trait indices and functional dispersion (FDis) of each individual trait; and (iii) the functional vulnerability at the community-level and species-level. The individual traits did not show a clear pattern along the chronosequence. However, the trend indicated an increase in the values of resource conservation traits with the age of abandonment. The functional response of the community did not vary between landscapes. Between DP and OF, there was a significant increase in functional diversity and a decrease in functional redundancy, which increased community-level vulnerability. Consequently, the more vulnerable species were observed in the IF and OF plots. In addition, a decrease in environmental parameters, such as penetration resistance, bulk density and Ca content, and an increase in slope, precipitation, electric conductivity, pH, clay, organic material, and P and N contents increased the vulnerability. We elucidated the need for secondary forest management in terms of conservation and restoration to maintain the capacity to respond to changing environmental conditions in highly fragmented landscapes in the Andean–Amazonian transition. [ABSTRACT FROM AUTHOR]

Questions: Ecological succession is the process during which ecosystems recover after disturbances. Studies investigating community reassembly during tropical forest succession have rarely compared lianas to trees. We addressed two questions: (1) how do changes in stem density, total basal area and species richness of lianas and trees compare throughout a secondary succession, and to what extent does the relative basal area of lianas change along a secondary succession; and (2) how do the successional trajectories of functional community trait values of lianas and trees compare? Location: Yoko forest reserve, central Congo basin. Methods: Using univariate Bayesian modeling techniques, we analyzed differences in successional pathways between lianas and trees in terms of community structure, and functional assembly in a replicated chronosequence spanning from young to old‐growth forests. Results: We found divergent structural trajectories between lianas and trees along the forest chronosequence. The stem density of lianas peaked at the intermediate stage, while that of trees almost linearly decreased from early to late stages of succession. The basal area of lianas increased at a higher rate than that of trees, which translated into a marginal increase of liana relative basal area over succession. On the contrary, we observed a lower rate of increase in species richness for lianas than trees over succession. We found a progressive convergence in the responses of lianas and trees to changes with succession in terms of specific leaf area and leaf nitrogen content, but a diverging response in terms of leaf phosphorus content. These functional composition patterns most probably resulted from environmental filtering, induced by a change from nitrogen to phosphorus limitation as the succession progressed to a mature forest. Conclusions: These findings underscore the rapid colonization of tropical forests by lianas after agricultural abandonment, presumably by deploying a more diverse leaf economic spectrum early in succession. [ABSTRACT FROM AUTHOR]

Question: Differences in understorey vegetation between ancient and recent forests have been thoroughly explored; however, few studies have investigated the legacies of different former land uses in recent forests. Indeed, due to more intense agricultural practices (tillage and fertilisation), legacy effects are expected to be stronger in former cropland or meadows than in former pastures. Our objectives were to compare soil conditions, taxonomic composition and functional composition of understorey plant communities in recent forests located on former pastures, meadows or cropland, with ancient forests as a reference. Location: Tarentaise Valley, Savoy, France. Methods: Based on land‐use maps surveyed between 1862 and 1864, we selected 82 forest sites with different former land uses in mountain forests in the French Alps and carried out soil sampling and botanical surveys. To account for potential confounding factors (altitude, canopy cover, tree species composition), we applied multiple linear regressions to analyse soil properties, canonical correspondence analysis to analyse plant taxonomic composition and multispecies generalised linear mixed‐effects models to analyse relationships between plant functional composition and former land uses. Results: The soils of former cropland were richer in nutrients and more alkaline compared to other past land uses, while soils on former pastures and meadows differed only slightly from ancient forests. Ancient forests were characterised by acidophilic, shade‐tolerant, low‐stature, forest‐dependent species, whereas former cropland was characterised by calcicolous non‐forest species. Former pasture and meadow communities displayed a distinct taxonomic composition compared to other past land uses, but a functional composition closer to ancient forest than to former cropland. Conclusion: Former cropland has a stronger legacy effect than former pastures or meadows. This could explain small differences between ancient and recent forests observed in previous studies conducted in mountain landscapes where former cropland was rare. [ABSTRACT FROM AUTHOR]

Abstract Forests play a key role in regulating the global carbon cycle, a substantial portion of which is stored in aboveground biomass (AGB). It is well understood that biodiversity can increase the biomass through complementarity and mass‐ratio effects, and the contribution of environmental factors and stand structure attributes to AGB was also observed. However, the relative influence of these factors in determining the AGB of Quercus forests remains poorly understood. Using a large dataset retrieved from 523 permanent forest inventory plots across Northeast China, we examined the effects of integrated multiple tree species diversity components (i.e., species richness, functional, and phylogenetic diversity), functional traits composition, environmental factors (climate and soil), stand age, and structure attributes (stand density, tree size diversity) on AGB based on structural equation models. We found that species richness and phylogenetic diversity both were not correlated with AGB. However, functional diversity positively affected AGB via an indirect effect in line with the complementarity effect. Moreover, the community‐weighted mean of specific leaf area and height increased AGB directly and indirectly, respectively; demonstrating the mass‐ratio effect. Furthermore, stand age, density, and tree size diversity were more important modulators of AGB than biodiversity. Our study highlights that biodiversity–AGB interaction is dependent on the regulation of stand structure that can be even more important for maintaining high biomass than biodiversity in temperate Quercus forests.

Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality. However, the importance of tree diversity in determining multifunctionality in structurally complex subtropical forests relative to other regulators (e.g., soil microbial diversity, stand structure, and environmental conditions) remains uncertain. In this study, effects of aboveground (species richness and functional and structural diversity) and belowground (bacterial and fungal diversity) biodiversity, functional composition (community-weighted means of species traits), stand structure (diameter at breast height and stand density), and soil factors (pH and bulk density) on multifunctionality (including biomass production, carbon stock, and nutrient cycling) were examined along a tree diversity gradient in subtropical forests. The community-weighted mean of tree maximum height was the best predictor of ecosystem multifunctionality. Functional diversity explained a higher proportion of the variation in multifunctionality than that of species richness and fungal diversity. Stand structure -played an important role in modulating the effects of tree diversity on multifunctionality. The work highlights that species composition and maximizing forest structural complexity are effective strategies to increase forest multifunctionality while also conserving biodiversity in the management of multifunctional forests under global environmental changes.

Understanding the impact of marine protected areas on the distribution and composition of fishes is key to the protection and management of coral reef ecosystems, and especially for fish-based activities such as SCUBA diving and recreational fishing. The aim of this research is to compare the ichthyofauna structure in three areas in the eastern part of Los Canarreos archipelago in Cuba with different management schemes: Cayo Campos-Cayo Rosario Fauna Refuge (CCCR), Cayo Largo Ecological Reserve (CL) and non-protected area (nMPA), and considering habitat differences and depth variation. A total of 131 video transects were conducted using diver operated stereo-video (stereo-DOV) in November, 2015 in backreef and forereef along the CCCR, CL and the adjacent nMPA. We recorded 84 species and 27 functional groups suggesting high complementarity of functions. Several multispecies schools were observed along surveys, which explain the biomass peaks in some sites, mainly for Lutjanidae, Haemulidae and Carangidae. A concerning issue was the bare representation of critical functional groups and threatened species. The effect of sites nested within habitats was significant and the most important driver structuring fish assemblages, while MPA condition was not evident. Favorable habitat features (habitat heterogeneity and surrounding coastal ecosystems) are likely enhancing fish assemblages and counteracting the effects of pouching derived from insufficient management. We recommend immediate actions within a strategy of precautionary management including, but not limited to, the appointment of staff for the administration of CL, frequent monitoring and effective enforcement. [ABSTRACT FROM AUTHOR]