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ispartof: AFRICAN JOURNAL OF ECOLOGY vol:60 issue:3 pages:668-681 status: published

Aim Soil microorganisms are essential for the functioning of terrestrial ecosystems. Although soil microbial communities and functions are linked to tree species composition and diversity, there has been no comprehensive study of the generality or context dependence of these relationships. Here, we examine tree diversity–soil microbial biomass and respiration relationships across environmental gradients using a global network of tree diversity experiments. Location Boreal, temperate, subtropical and tropical forests. Time period 2013. Major taxa studied Soil microorganisms. Methods Soil samples collected from 11 tree diversity experiments were used to measure microbial respiration, biomass and respiratory quotient using the substrate-induced respiration method. All samples were measured using the same analytical device, method and procedure to reduce measurement bias. We used linear mixed-effects models and principal components analysis (PCA) to examine the effects of tree diversity (taxonomic and phylogenetic), environmental conditions and interactions on soil microbial properties. Results Abiotic drivers, mainly soil water content, but also soil carbon and soil pH, significantly increased soil microbial biomass and respiration. High soil water content reduced the importance of other abiotic drivers. Tree diversity had no effect on the soil microbial properties, but interactions with phylogenetic diversity indicated that the effects of diversity were context dependent and stronger in drier soils. Similar results were found for soil carbon and soil pH. Main conclusions Our results indicate the importance of abiotic variables, especially soil water content, for maintaining high levels of soil microbial functions and modulating the effects of other environmental drivers. Planting tree species with diverse water-use strategies and structurally complex canopies and high leaf area might be crucial for maintaining high soil microbial biomass and respiration. Given that greater phylogenetic distance alleviated unfavourable soil water conditions, reforestation efforts that account for traits improving soil water content or select more phylogenetically distant species might assist in increasing soil microbial functions.

Grassland is the primary land use in China, which has experienced extensive degradation in recent decades due to overexploitation. Here, we conducted field experiments to quantify the degraded grassland’s recovery rate in Northeast Inner Mongolia in response to restoration measures, including fallow + enclosure (FE) and mowing + enclosure (ME) in comparison to livestock grazing (LG), since 2005. Plant community properties were surveyed and aboveground biomass (AGB) sampled in summer 2013. Our results showed that the regional dominant species Leymus chinensis retained its dominance under FE, whereas a range of forb species gained dominance under LG. Vegetative cover was maximal under FE and minimal under LG. The least amount of vegetation development and AGB were observed under LG. However, plant diversity showed an opposite pattern, with maximal diversity under LG and minimal under FE. Statistical analysis revealed that AGB was negatively associated with plant diversity for all treatments except ME. For ME, a positive AGB-diversity relationship was characterized, suggesting that mowing intensity was a controlling factor for the AGB-diversity relationship. Overall, these results demonstrated that enclosure plus mowing represented an effective conservation measure that provided fair support to forage production and a progressive pathway to a more resilient grassland system.

One of the primary goals of macroevolutionary biology has been to explain general trends in long‐term diversity patterns, including whether such patterns correspond to an upscaling of processes occurring at lower scales. Reconstructed phylogenies often show decelerated lineage accumulation over time. This pattern has often been interpreted as the result of diversity‐dependent (DD) diversification, where the accumulation of species causes diversification to decrease through niche filling. However, other processes can also produce such a slowdown, including time dependence without diversity dependence. To test whether phylogenetic branching patterns can be used to distinguish these two mechanisms, we formulated a time‐dependent, but diversity‐independent model that matches the expected diversity through time of a DD model. We simulated phylogenies under each model and studied how well likelihood methods could recover the true diversification mode. Standard model selection criteria always recovered diversity dependence, even when it was not present. We correct for this bias by using a bootstrap method and find that neither model is decisively supported. This implies that the branching pattern of reconstructed trees contains insufficient information to detect the presence or absence of diversity dependence. We advocate that tests encompassing additional data, for example, traits or range distributions, are needed to evaluate how diversity drives macroevolutionary trends.

It is time to synthesize the knowledge that has been generated through more than 260 years of botanical exploration, taxonomic and, more recently, phylogenetic research throughout the world. The adoption of an updated Global Strategy for Plant Conservation (GSPC) in 2011 provided the essential impetus for the development of the World Flora Online (WFO) project. The project represents an international, coordinated effort by the botanical community to achieve GSPC Target 1, an electronic Flora of all plants. It will be a first‐ever unique and authoritative global source of information on the world's plant diversity, compiled, curated, moderated and updated by an expert and specialist‐based community (Taxonomic Expert Networks – “TENs” – covering a taxonomic group such as family or order) and actively managed by those who have compiled and contributed the data it includes. Full credit and acknowledgement will be given to the original sources, allowing users to refer back to the primary data. A strength of the project is that it is led and endorsed by a global consortium of more than 40 leading botanical institutions worldwide. A first milestone for producing the World Flora Online is to be accomplished by the end of 2020, but the WFO Consortium is committed to continuing the WFO programme beyond 2020 when it will develop its full impact as the authoritative source of information on the world's plant biodiversity.

Aim Rates of colonization, speciation and extinction determine species richness and endemism in insular systems. The general dynamic model of island biogeography (GDM) predicts that speciation and extinction rates depend on island area and elevation via their control on ecological limits to diversification and therefore covary with an island's geological history. Additionally, the colonization rate may increase with area and elevation through the 'target effect', which can be mediated by reduced 'environmental filtering'. Here we test whether the area and depth expansion of an island-like ecosystem, a lake, caused a shift in diversity dynamics. Location Lake Biwa, Japan, whose geological history and biota are well documented. Taxon Fishes. Methods We extended the phylogenetic island biogeography framework DAISIE (Dynamic Assembly of Island biota through Speciation, Immigration and Extinction) to accommodate time-shifts in macroevolutionary rates and in carrying capacity. Using phylogenetic information on colonization and speciation times for the complete Lake Biwa fish community (70 taxa), we tested for a shift in macroevolutionary assembly rates and reconstructed the temporal diversity trajectory in the lake. We assessed the power to identify a shift through a wide range of scenarios and benchmarked against simulated fossil records. Results We detected an increase in colonization rate of fishes at 0.2 million years ago (Ma), with limited support for the existence of ecological limits. The reconstructed diversity trajectory was close to a source-sink equilibrium diversity prior to the shift and remained well below a new shift-driven elevated equilibrium thereafter. We found sufficient power to identify an increase in colonization rate up to 1.5 Ma, whereas extinction concealed the signal of earlier shifts. Main conclusions The fish diversity dynamics of Lake Biwa show a response to changes in area and depth and phylogenies carry a signature of these changes. The detected increase in colonization rate following Lake Biwa's expansion, elevating the fish diversity, is unlikely due to a predicted increase in ecological limits feeding back on colonization rate. We therefore call for (additional) explanations: the target effect, whereby larger islands attract more species, and reduced environmental filtering due to higher habitat diversity associated with increased lake area/depth.

Understanding how and why rates of evolutionary diversification vary is a key issue in evolutionary biology, ecology, and biogeography. Evolutionary rates are the net result of interacting processes summarized under concepts such as adaptive radiation and evolutionary stasis. Here, we review the central concepts in the evolutionary diversification literature and synthesize these into a simple, general framework for studying rates of diversification and quantifying their underlying dynamics, which can be applied across clades and regions, and across spatial and temporal scales. Our framework describes the diversification rate (d) as a function of the abiotic environment (a), the biotic environment (b), and clade-specific phenotypes or traits (c); thus, d ~ a,b,c. We refer to the four components (a–d) and their interactions collectively as the “Evolutionary Arena.” We outline analytical approaches to this framework and present a case study on conifers, for which we parameterize the general model. We also discuss three conceptual examples: the Lupinus radiation in the Andes in the context of emerging ecological opportunity and fluctuating connectivity due to climatic oscillations; oceanic island radiations in the context of island formation and erosion; and biotically driven radiations of the Mediterranean orchid genus Ophrys. The results of the conifer case study are consistent with the long-standing scenario that low competition and high rates of niche evolution promote diversification. The conceptual examples illustrate how using the synthetic Evolutionary Arena framework helps to identify and structure future directions for research on evolutionary radiations. In this way, the Evolutionary Arena framework promotes a more general understanding of variation in evolutionary rates by making quantitative results comparable between case studies, thereby allowing new syntheses of evolutionary and ecological processes to emerge.

Aim To explore the impact of island area and isolation on multiple dimensions of ant biodiversity (taxonomic, phylogenetic and functional diversity) and the underlying processes of community assembly on islands.Location Thousand Island Lake, Zhejiang, China, created by dam construction in 1959.Taxon Ants.Methods We sampled ants on 33 islands, built a species-level phylogenetic tree and measured five morphological traits of all species collected to estimate taxonomic, phylogenetic and functional diversity. We used multiple linear regression models and null models to examine the relationships between diversity metrics and island variables (area and isolation).Results We recorded 97 ant species on the study islands. We verified positive diversity-area relationships for species richness, phylogenetic diversity and functional diversity. However, although functional and phylogenetic community structure were indistinguishable from random communities, phylogenetic structure tended to be clustered, whereas functional structure tended to be overdispersed. Additionally, we found the structure of ant communities shifted from phylogenetic and functional clustering on smaller islands to phylogenetic and functional overdispersion on larger islands.Main conclusions Our results support the hypothesis that environmental filtering is the dominant process structuring ant communities on smaller islands, and that competitive exclusion becomes more important on larger islands. Thus, island area acts as an important filter even though ant community structure on the study islands was indistinguishable from random communities. Moreover, our results show that environmental filtering influences phylogenetic community structure of ants, whereas competitive exclusion influences functional community structure of ants. These findings highlight the need to examine both phylogenetic and functional diversity in order to understand the mechanisms that govern the assembly of natural communities on islands.

Correction Volume 68 Issue 3 Article Number39 DOI 10.1007/s10344-022-01591-w Published JUN 2022 The number of wetlands in Europe decreased by more than 60% by the 1990s compared with the beginning of the twentieth century. Man-made wetlands may be an effective way to compensate for the loss and degradation of freshwater ecosystems. This loss impacts the populations of declining duck species, partly due to a lack of suitable breeding opportunities. In this study, we evaluated duck productivity and invertebrate abundance in 13 man-made Finnish wetlands that were created for waterbirds. Our findings revealed that man-made wetlands have higher duck production than average natural boreal lakes. High invertebrate levels were a key factor that positively correlated with duck pair density, brood density, duckling density of the common teal (Anas crecca), and duck density during the post-breeding period. Our results suggest that man-made wetlands are a useful tool for increasing duck productivity. For upholding this status in the long term, appropriate management should involve maintaining sufficient invertebrate levels.

Agricultural expansion drives biodiversity decline in forested tropical regions. Consequently, it is important to understand the conservation value of remnant forest in production landscapes. In a tropical landscape dominated by oil palm we characterized faunal communities across eight taxa occurring within riparian forest buffers, which are legally protected alongside rivers, and compared them to nearby recovering logged forest. Buffer width was the main predictor of species richness and abundance, with widths of 40-100 m on each side of the river supporting broadly equivalent levels of biodiversity to logged forest. However, width responses varied markedly among taxa, and buffers often lacked forest-dependent species. Much wider buffers than are currently mandated are needed to safeguard most species. The largest biodiversity gains are achieved by increasing relatively narrow buffers. To provide optimal conservation outcomes in tropical production landscapes we encourage policymakers to prescribe width requirements for key taxa and different landscape contexts., Newton-Ungku Omar Fund (grants 216433953, 537134717) – delivered by the British Council and funded by the UK Department for Business, Energy and Industrial Strategy and the Malaysian Industry-Government Group for High Technology – as well as the UK Natural Environment Research Council (NE/K016407/1, NE/K016261/1; https://lombok.nerc-hmtf.info/). MJS was supported by a Research Leadership Award from the Leverhulme Trust.

Funding biodiversity conservation strategies are usually minimal, thus prioritizing habitats at high risk should be conducted. We developed and tested a conservation priority index (CPI) that ranks habitats to aid in prioritizing them for conservation. We tested the index using 1897 fish species from 273 African inland lakes and 34 countries. In the index, lake surface area, rarity, and their International Union for Conservation of Nature (IUCN) Red List status were incorporated. We retrieved data from the Global Biodiversity Information Facility (GBIF) and IUCN data repositories. Lake Nyasa had the highest species richness (424), followed by Tanganyika (391), Nokoué (246), Victoria (216), and Ahémé (216). However, lakes Otjikoto and Giunas had the highest CPI of 137.2 and 52.1, respectively. Lakes were grouped into high priority (CPI > 0.5; n = 56) and low priority (CPI

This paper is part of the project “Ecological Engineering as a Biodiversity Driver in Deep Time,” funded by the Academy of Finland, and is a contribution to the IGCP program 653 “The Onset of the Great Ordovician Biodiversification Event.” O.H. acknowledges support from the Estonian Research Council grant PRG836. The Ordovician-Silurian (similar to 485-419 Ma) was a time of considerable evolutionary upheaval, encompassing both great evolutionary diversification and one of the first major mass extinctions. The Ordovician diversification coincided with global climatic cooling and paleocontinental collision, the ecological impacts of which were mediated by region-specific processes including substrate changes, biotic invasions, and tectonic movements. From the Sandbian-Katian (similar to 453 Ma) onward, an extensive carbonate shelf developed in the eastern Baltic paleobasin in response to a tectonic shift to tropical latitudes and an increase in the abundance of calcareous macroorganisms. We quantify the contributions of environmental differentiation and temporal turnover to regional diversity through the Ordovician and Silurian, using brachiopod occurrences from the more shallow-water facies belts of the eastern Baltic paleobasin, an epicontinental sea on the Baltica paleocontinent. The results are consistent with carbonate shelf development as a driver of Ordovician regional diversification, both by enhancing broadscale differentiation between shallow- and deep-marine environments and by generating heterogeneous carbonate environments that allowed increasing numbers of brachiopod genera to coexist. However, temporal turnover also contributed significantly to apparent regional diversity, particularly in the Middle-Late Ordovician. Publisher PDF

The responses of biotic communities and ecosystems to climate change may be abrupt and non-linear. Thus, resolving ecological threshold mechanisms is crucial for understanding the consequences of climate change and for improving environmental management. Here, we present a study on the threshold responses of benthic diatom communities that are an important component of all aquatic environments and strongly contribute to global primary production. We reach beyond the taxonomic perspective by focusing on the diversity and functions of diatom communities and benthic biomass along gradients of salinity and wind disturbance, whose climate-change-induced changes have been predicted to strongly affect biotic communities in the marine and brackish systems in the future. To improve the generality of our results, we examine three self-collected datasets from different spatial scales (6-830 km) and ecosystem types. We collected samples from rock pools or from littoral stones and studied taxonomic thresholds using Threshold Indicator Taxa Analysis (TITAN2). We investigated threshold responses of community diversity, community functions, and benthic biomass using t-tests and regression analyses. Our results indicated that decreasing salinity may result in increasing diver-sity but decreasing biomass of brackish communities, while the effects of increasing wind disturbance were contradictory among spatial scales. Benthic biomass correlated with the taxonomic and functional diversity, as well as with the body size distribution of communities, highlighting the importance of considering community functions and organismal size when predicting ecosystem functions. The most pronounced effects of decreasing salinity and increasing wind distur-bance on community functions were changes in the abundance of low-profile diatom species, which, due to the high resilience of low-profile diatoms, may lead to changes in ecosystem functioning and resilience. To conclude, decreasing salinity and increasing wind disturbance may lead to threshold responses of biotic communities, and these changes may have profound effects on ecosystem functioning along marine coastal areas.

In the face of ongoing habitat degradation and the biodiversity crisis, natural reserves are important refuges for wildlife. Since most free-living organisms serve as hosts to parasites, the diverse communities in protected areas can be expected to provide suitable habitats for a species-rich parasite fauna. However, to date, assessments of parasite diversity in protected nature reserves are rare. To expand our knowledge of parasite communities in natural habitats, we examined 1994 molluscs belonging to 15 species for trematode infections in a central European natural reserve. The parasitological examination revealed an overall prevalence of 17.3% and a total species richness of 40 trematode species. However, the parasite diversity and prevalence did not differ markedly from trematode communities in non-protected environments, which might be partly explained by a dilution effect caused by a high number of non-host organisms in our study system. The proportion of complex and long life cycles of parasites in the present study is high, indicating complex biotic interactions. We conclude that life cycle complexity, in addition to parasite diversity and trematode species richness, can provide valuable information on ecosystem health and should therefore be considered in future studies.

Measuring commonness and rarity is pivotal to ecology and conservation. Zeta diversity, the average number of species shared by multiple sets of assemblages, and Dark diversity, the number of species that could occur in an assemblage but are missing, have been recently proposed to capture two aspects of the commonness‐rarity spectrum. Despite a shared focus on commonness and rarity, thus far, Zeta and Dark diversities have been assessed separately. Here, we review these two frameworks and suggest their integration into a unified paradigm of the “rarity facets of biodiversity.” This can be achieved by partitioning Alpha and Beta diversities into five components (the Zeta, Eta, Theta, Iota, and Kappa rarity facets) defined based on the commonness and rarity of species. Each facet is assessed in traditional and multiassemblage fashions to bridge conceptual differences between Dark diversity and Zeta diversity. We discuss applications of the rarity facets including comparing the taxonomic, functional, and phylogenetic diversity of rare and common species, or measuring species' prevalence in different facets as a metric of species rarity. The rarity facets integrate two emergent paradigms in biodiversity science to better understand the ecology of commonness and rarity, an important endeavor in a time of widespread changes in biodiversity across the Earth., Despite a shared focus on commonness and rarity, Zeta diversity (average number of species shared by multiple sets of assemblages) and Dark diversity (species that could occur in an assemblage but are missing) have been thus far separate paradigms. We suggest integrating them into a unified framework of the “rarity facets of biodiversity” that integrate two emergent paradigms in biodiversity science to better understand the ecology of commonness and rarity. This is an important endeavor in a time of widespread changes in biodiversity across the Earth.

In many regions across the globe, extreme weather events such as storms have increased in frequency, intensity, and duration due to climate change. Ecological theory predicts that such extreme events should have large impacts on ecosystem structure and function. High winds and precipitation associated with storms can affect lakes via short‐term runoff events from watersheds and physical mixing of the water column. In addition, lakes connected to rivers and streams will also experience flushing due to high flow rates. Although we have a well‐developed understanding of how wind and precipitation events can alter lake physical processes and some aspects of biogeochemical cycling, our mechanistic understanding of the emergent responses of phytoplankton communities is poor. Here we provide a comprehensive synthesis that identifies how storms interact with lake and watershed attributes and their antecedent conditions to generate changes in lake physical and chemical environments. Such changes can restructure phytoplankton communities and their dynamics, as well as result in altered ecological function (e.g., carbon, nutrient and energy cycling) in the short‐ and long‐term. We summarize the current understanding of storm‐induced phytoplankton dynamics, identify knowledge gaps with a systematic review of the literature, and suggest future research directions across a gradient of lake types and environmental conditions., Our understanding of ecosystem‐scale responses to storm events is fragmented, and terminological variability in defining a “storm” hinders resolution of generalizable impacts. We provide a comprehensive synthesis of the interactions between physical properties and biological responses in lakes that demonstrates the context‐dependency of storm impacts; lake/watershed attributes and their antecedent conditions mediate the extent to which storms impact lake ecosystems. We develop a framework which conceptualizes how abrupt, storm‐induced changes in the lake environment influence phytoplankton community dynamics through functional traits, identifies current limitations, and highlights several avenues of research to narrow knowledge gaps in synthetic and interdisciplinary ways.

Lichens have a vital role in forest ecosystems and they are a threatened group in boreal forests. However, the conservation ecology of the total lichen community has very rarely been studied. Here we studied lichen species and communities, including macrolichens (=foliose and fruticose growth forms) and rarely studied crustose li-chens, on decaying wood in boreal spruce-dominated forests in Finland. We also studied obligate lignicoles that grow only on dead wood and are mostly crustose in growth form. Species richness and community composition were examined on decaying logs and natural or cut stumps of Picea abies at different decay stages (2-5) in 14 stands, half of which were natural or seminatural and half recently managed. We used thorough search to yield a species list as close to complete as possible. Our study questions were: 1) Are species richness and lichen communities different in natural and managed forests, and if so, are there differences between macrolichens, crustose lichens and obligate lignicoles in how they respond to forest management? 2) How does the decay stage and dead wood type affect the lichens, i.e. are there differences between stumps and logs? We found a total of 127 lichen species. Most (75 %) of the recorded lichen species were crustose. With a generalized linear model we found that crustose lichens and obligate lignicoles had a higher species richness in natural than managed forests, but macrolichen richness was not significantly affected by forest management. Utilizing non-metric multidi-mensional scaling we discovered that site level community composition of macrolichens, crustose lichens and obligate lignicoles was also significantly different between natural and managed forests. We found that on dead wood unit level the decay stage had a significant effect on species richness and community composition, so that the species richness of all studied groups declined during the decay process. The dead wood type (stump vs log) had a significant effect on species richness of macrolichens and obligate lignicoles, both for which species richness was higher on logs than on stumps, as well as on the communities of crustose lichens.

A popular idea in ecology is that trait variation among individuals from the same species may promote the coexistence of competing species. However, theoretical and empirical tests of this idea have yielded inconsistent findings. We manipulated intraspecific trait diversity in a ciliate competing with a nematode for bacterial prey in experimental microcosms. We found that intraspecific trait variation inverted the original competitive hierarchy to favor the consumer with variable traits, ultimately resulting in competitive exclusion. This competitive outcome was driven by foraging traits (size, speed, and directionality) that increased the ciliate’s fitness ratio and niche overlap with the nematode. The interplay between consumer trait variation and competition resulted in non-additive cascading effects - mediated through prey defense traits - on prey community assembly. Our results suggest that predicting consumer competitive population dynamics and the assembly of prey communities will require understanding the complexities of trait variation within consumer species.

International audience; Declines of large predatory fish due to overexploitation are restructuring food webs across the globe. It is now becoming evident that restoring these altered food webs requires addressing not only ecological processes, but evolutionary ones as well, because human-induced rapid evolution may in turn affect ecological dynamics. We studied the potential for niche differentiation between different plate armor phenotypes in a rapidly expanding population of a small prey fish, the three-spined stickleback (Gasterosteus aculeatus). In the central Baltic Sea, three-spined stickleback abundance has increased dramatically during the past decades. The increase in this typical mesopredator has restructured near-shore food webs, increased filamentous algal blooms, and threatens coastal biodiversity. Time-series data covering 22 years show that the increase coincides with a decline in the number of juvenile perch (Perca fluviatilis), the most abundant predator of stickleback along the coast. We investigated the distribution of different stickleback plate armor phenotypes depending on latitude, environmental conditions, predator and prey abundances, nutrients, and benthic production; and described the stomach content of the stickleback phenotypes using metabarcoding. We found two distinct lateral armor plate phenotypes of stickleback, incompletely and completely plated. The proportion of incompletely plated individuals increased with increasing benthic production and decreasing abundances of adult perch. Metabarcoding showed that the stomach content of the completely plated individuals more often contained invertebrate herbivores (amphipods) than the incompletely plated ones. Since armor plates are defense structures favored by natural selection in the presence of fish predators, the phenotype distribution suggests that a novel low-predation regime favors stickleback with less armor. Our results suggest that morphological differentiation of the three-spined stickleback has the potential to affect food web dynamics and influence the persistence and resilience of the stickleback take-over in the Baltic Sea.

Macrofauna are an abundant and diverse component of abyssal benthic communities and are likely to be heavily impacted by polymetallic nodule mining in the Clarion-Clipperton Zone (CCZ). In 2012, the International Seabed Authority (ISA) used available benthic biodiversity data and environmental proxies to establish nine no-mining areas, called Areas of Particular Environmental Interest (APEIs) in the CCZ. The APEIs were intended as a representative system of protected areas to safeguard biodiversity and ecosystem function across the region from mining impacts. Since 2012, a number of research programs have collected additional ecological baseline data from the CCZ. We assemble and analyze macrofaunal biodiversity data sets from eight studies, focusing on three dominant taxa (Polychaeta, Tanaidacea, and Isopoda), and encompassing 477 box-core samples to address the following questions: (1) How do macrofaunal abundance, biodiversity, and community structure vary across the CCZ, and what are the potential ecological drivers? (2) How representative are APEIs of the nearest contractor areas? (3) How broadly do macrofaunal species range across the CCZ region? and (4) What scientific gaps hinder our understanding of macrofaunal biodiversity and biogeography in the CCZ? Our analyses led us to hypothesize that sampling efficiencies vary across macrofaunal data sets from the CCZ, making quantitative comparisons between studies challenging. Nonetheless, we found that macrofaunal abundance and diversity varied substantially across the CCZ, likely due in part to variations in particulate organic carbon (POC) flux and nodule abundance. Most macrofaunal species were collected only as singletons or doubletons, with additional species still accumulating rapidly at all sites, and with most collected species appearing to be new to science. Thus, macrofaunal diversity remains poorly sampled and described across the CCZ, especially within APEIs, where a total of nine box cores have been taken across three APEIs. Some common macrofaunal species ranged over 600–3000 km, while other locally abundant species were collected across ≤ 200 km. The vast majority of macrofaunal species are rare, have been collected only at single sites, and may have restricted ranges. Major impediments to understanding baseline conditions of macrofaunal biodiversity across the CCZ include: (1) limited taxonomic description and/or barcoding of the diverse macrofauna, (2) inadequate sampling in most of the CCZ, especially within APEIs, and (3) lack of consistent sampling protocols and efficiencies.

Deep seabed mining is potentially imminent in the Clarion Clipperton Fracture Zone (CCFZ; northeast Pacific). Seabed collectors will remove polymetallic nodules and the surrounding surface sediments, both inhabited by meiofauna, along their path. To determine potential impacts of polymetallic nodule removal, we investigated the importance of nodule presence for the abundance, composition and diversity of sediment meiofauna, and evaluated the existence and composition of nodule crevice meiofauna in the Global Sea Mineral Resources (GSR) exploration contract area. Nodule-free and nodule-rich sediments displayed high biodiversity with many singletons and doubletons, potentially representing rare taxa. Nodule presence negatively influenced sediment meiofaunal abundances but did not markedly affect taxonomic composition or diversity. This is the first report on CCFZ nodule crevice meiofauna, whose abundance related positively to nodule dimensions. Though dominated by the same taxa, nodules and sediments differed regarding the taxonomic and trophic composition of the meio- and nematofauna. Nevertheless, there were no taxa endemic to the nodule crevices and nodule crevice meiofauna added only little to total small-scale (~ cm) meiofaunal abundance and diversity. We formulated environmental management recommendations at the contract area and regional (CCFZ) scale related to sampling effort, set-aside preservation and monitoring areas, and potential rehabilitation measures. ispartof: SCIENTIFIC REPORTS vol:11 issue:1 ispartof: location:England status: published

Novel species of fungi described in this study include those from various countries as follows: Algeria, Phaeoacremonium adelophialidum from Vitis vinifera. Antarctica, Comoclathris antarctica from soil. Australia, Coniochaeta salicifolia as endophyte from healthy leaves of Geijera salicifolia, Eremothecium peggii in fruit of Citrus australis, Microdochium ratticaudae from stem of Sporobolus natalensis, Neocelosporium corymbiae on stems of Corymbia variegata, Phytophthora kelmanii from rhizosphere soil of Ptilotus pyramidatus, Pseudosydowia backhousiae on living leaves of Backhousia citriodora, Pseudosydowia indoor oopillyensis, Pseudosydowia louisecottisiae and Pseudosydowia queenslandica on living leaves of Eucalyptus sp. Brazil, Absidia montepascoalis from soil. Chile, Ilyonectria zarorii from soil under Maytenus boaria. Costa Rica, Colletotrichum filicis from an unidentified fern. Croatia, Mollisia endogranulata on deteriorated hardwood. Czech Republic, Arcopilus navicularis from tea bag with fruit tea, Neosetophoma buxi as endophyte from Buxus sempervirens, Xerochrysium bohemicum on surface of biscuits with chocolate glaze and filled with jam. France, Entoloma cyaneobasale on basic to calcareous soil, Fusarium aconidiale from Triticum aestivum, Fusarium juglandicola from buds of Juglans regia. Germany, Tetraploa endophytica as endophyte from Microthlaspi perfoliatum roots. India, Castanediella ambae on leaves of Mangifera indica, Lactifluus kanadii on soil under Castanopsis sp., Penicillium uttarakhandense from soil. Italy, Penicillium ferraniaense from compost. Namibia, Bezerromyces gobabebensis on leaves of unidentified succulent, Cladosporium stipagrostidicola on leaves of Stipagrostis sp., Cymostachys euphorbiae on leaves of Euphorbia sp., Deniquelata hypolithi from hypolith under a rock, Hysterobrevium walvisbayicola on leaves of unidentified tree, Knufia hypolithi and Knufia walvisbayicola from hypolith under a rock, Lapidomyces stipagrostidicola on leaves of Stipagrostis sp., Nothophaeotheca mirabibensis (incl. Nothophaeotheca gen. nov.) on persistent inflorescence remains of Blepharis obmitrata, Paramyrothecium salvadorae on twigs of Salvadora persica, Preussia procaviicola on dung of Procavia sp., Sordaria equicola on zebra dung, Volutella salvadorae on stems of Salvadora persica. Netherlands, Entoloma ammophilum on sandy soil, Entoloma pseudocruentatum on nutrient poor(acid)soil, Entoloma pudens on plant debris, amongst grasses. [...], Leslie W.S. de Freitas and colleagues express their gratitude to Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for scholarships provided to Leslie Freitas and for the research grant provided to André Luiz Santiago; their contribution was financed by the projects ‘Diversity of Mucoromycotina in the different ecosystems of the Atlantic Rainforest of Pernambuco’ (FACEPE–First Projects Program PPP/ FACEPE/CNPq–APQ–0842-2.12/14) and ‘Biology of conservation of fungi s.l. in areas of Atlantic Forest of Northeast Brazil’ (CNPq/ICMBio 421241/ 2017-9) H.B. Lee was supported by the Graduate Program for the Undiscovered Taxa of Korea (NIBR202130202). The study of O.V. Morozova, E.F. Malysheva, V.F. Malysheva, I.V. Zmitrovich, and L.B. Kalinina was carried out within the framework of a research project of the Komarov Botanical Institute RAS (АААА-А19-119020890079-6) using equipment of its Core Facility Centre ‘Cell and Molecular Technologies in Plant Science’. The work of O. V. Morozova, L.B. Kalinina, T. Yu. Svetasheva, and E.A. Zvyagina was financially supported by Russian Foundation for Basic Research project no. 20-04-00349. E.A. Zvyagina and T.Yu. Svetasheva are grateful to A.V. Alexandrova, A.E. Kovalenko, A.S. Baykalova for the loan of specimens, T.Y. James, E.F. Malysheva and V.F. Malysheva for sequencing. J.D. Reyes acknowledges B. Dima for comparing the holotype sequence of Cortinarius bonachei with the sequences in his database. A. Mateos and J.D. Reyes acknowledge L. Quijada for reviewing the phylogeny and S. de la Peña- Lastra and P. Alvarado for their support and help. Vladimir I. Kapitonov and colleagues are grateful to Brigitta Kiss for help with their molecular studies. This study was conducted under research projects of the Tobolsk Complex Scientific Station of the Ural Branch of the Russian Academy of Sciences (N АААА-А19-119011190112-5). E. Larsson acknowledges the Swedish Taxonomy Initiative, SLU Artdatabanken, Uppsala (dha.2019.4.3-13). The study of D.B. Raudabaugh and colleagues was supported by the Schmidt Science Fellows, in partnership with the Rhodes Trust. Gregorio Delgado is grateful to Michael Manning and Kamash Pillai (Eurofins EMLab P&K) for provision of laboratory facilities. Jose G. Maciá-Vicente acknowledges support from the German Research Foundation under grant MA7171/1-1, and from the Landes-Offensive zur Entwicklung Wissenschaftlich-ökonomischer Exzellenz (LOEWE) of the state of Hesse within the framework of the Cluster for Integrative Fungal Research (IPF). Thanks are also due to the authorities of the Cabañeros National Park and Los Alcornocales Natural Park for granting the collection permit and for support during field work. The study of Alina V. Alexandrova was carried out as part of the Scientific Project of the State Order of the Government of Russian Federation to Lomonosov Moscow State University No. 121032300081-7. Michał Gorczak was financially supported by the Ministry of Science and Higher Education through the Faculty of Biology, University of Warsaw intramural grant DSM 0117600- 13. M. Gorczak acknowledges M. Klemens for sharing a photo of the Białowieża Forest logging site and M. Senderowicz for help with preparing the illustration. Ivona Kautmanová and D. Szabóová were funded by the Operational Program of Research and Development and co-financed with the European Fund for Regional Development (EFRD). ITMS 26230120004: ‘Building of research and development infrastructure for investigation of genetic biodiversity of organisms and joining IBOL initiative’. Ishika Bera, Aniket Ghosh, Jorinde Nuytinck and Annemieke Verbeken are grateful to the Director, Botanical Survey of India (Kolkata), Head of the Department of Botany & Microbiology & USIC Dept. HNB Garhwal University, Srinagar, Garhwal for providing research facilities. Ishika Bera and Aniket Ghosh acknowledge the staff of the forest department of Arunachal Pradesh for facilitating the macrofungal surveys to the restricted areas. Sergey Volobuev was supported by the Russian Science Foundation (RSF project N 19-77- 00085). Aleksey V. Kachalkin and colleagues were supported by the Russian Science Foundation (grant No. 19-74-10002). The study of Anna M. Glushakova was carried out as part of the Scientific Project of the State Order of the Government of Russian Federation to Lomonosov Moscow State University No. 121040800174-6. Tracey V. Steinrucken and colleagues were supported by AgriFutures Australia (Rural Industries Research and Development Corporation), through funding from the Australian Government Department of Agriculture, Water and the Environment, as part of its Rural Research and Development for Profit program (PRJ-010527). Neven Matočec and colleagues thank the Croatian Science Foundation for their financial support under the project grant HRZZ-IP-2018-01-1736 (ForFungiDNA). Ana Pošta thanks the Croatian Science Foundation for their support under the grant HRZZ-2018-09-7081. The research of Milan Spetik and co-authors was supported by Internal Grant of Mendel University in Brno No. IGAZF/ 2021-SI1003. K.C. Rajeshkumar thanks SERB, the Department of Science and Technology, Government of India for providing financial support under the project CRG/2020/000668 and the Director, Agharkar Research Institute for providing research facilities. Nikhil Ashtekar thanks CSIR-HRDG, INDIA, for financial support under the SRF fellowship (09/670(0090)/2020-EMRI), and acknowledges the support of the DIC Microscopy Facility, established by Dr Karthick Balasubramanian, B&P (Plants) Group, ARI, Pune. The research of Alla Eddine Mahamedi and co-authors was supported by project No. CZ.02.1.01/0.0/0.0/16_017/0002334, Czech Republic. Tereza Tejklová is thanked for providing useful literature. A. Polhorský and colleagues were supported by the Operational Program of Research and Development and co-financed with the European fund for Regional Development (EFRD), ITMS 26230120004: Building of research and development infrastructure for investigation of genetic biodiversity of organisms and joining IBOL initiative. Yu Pei Tan and colleagues thank R. Chen for her technical support. Ernest Lacey thanks the Cooperative Research Centres Projects scheme (CRCPFIVE000119) for its support. Suchada Mongkolsamrit and colleagues were financially supported by the Platform Technology Management Section, National Center for Genetic Engineering and Biotechnology (BIOTEC), Project Grant No. P19-50231. Dilnora Gouliamova and colleagues were supported by a grant from the Bulgarian Science Fund (KP-06-H31/19). The research of Timofey A. Pankratov was supported by the Russian Foundation for Basic Research (grant No. 19-04-00297a). Gabriel Moreno and colleagues wish to express their gratitude to L. Monje and A. Pueblas of the Department of Drawing and Scientific Photography at the University of Alcalá for their help in the digital preparation of the photographs, and to J. Rejos, curator of the AH herbarium, for his assistance with the specimens examined in the present study. Vit Hubka was supported by the Charles University Research Centre program No. 204069. Alena Kubátová was supported by The National Programme on Conservation and Utilization of Microbial Genetic Resources Important for Agriculture (Ministry of Agriculture of the Czech Republic). The Kits van Waveren Foundation (Rijksherbariumfonds Dr E. Kits van Waveren, Leiden, Netherlands) contributed substantially to the costs of sequencing and travelling expenses for M. Noordeloos. The work of B. Dima was supported by the ÚNKP-20-4 New National Excellence Program of the Ministry for Innovation and Technology from the source of the National Research, Development and Innovation Fund, and by the ELTE Thematic Excellence Programme 2020 supported by the National Research, Development and Innovation Office of Hungary (TKP2020-IKA-05). The Norwegian Entoloma studies received funding from the Norwegian Biodiversity Information Centre (NBIC), and the material was partly sequenced through NorBOL. Gunnhild Marthinsen and Katriina Bendiksen (Natural History Museum, University of Oslo, Norway) are acknowledged for performing the main parts of the Entoloma barcoding work. Asunción Morte is grateful to AEI/FEDER, UE (CGL2016-78946-R) and Fundación Séneca - Agencia de Ciencia y Tecnología de la Región de Murcia (20866/PI/18) for financial support. Vladimír Ostrý was supported by the Ministry of Health, Czech Republic - conceptual development of research organization (National Institute of Public Health – NIPH, IN 75010330). Konstanze Bensch (Westerdijk Fungal Biodiversity Institute, Utrecht) is thanked for correcting the spelling of various Latin epithets.

The findings that some plants alter their competitive phenotype in response to genetic relatedness of its conspecific neighbour (and presumed competitor) has spurred an increasing interest in plant kin-interactions. This phenotypic response suggests the ability to assess the genetic relatedness of conspecific competitors, proposing kin selection as a process that can influence plant competitive interactions. Kin selection can favour restrained competitive growth towards kin, if the fitness loss from reducing own growth is compensated by increased fitness in the related neighbour. This may lead to positive frequency dependency among related conspecifics with important ecological consequences for species assemblage and coexistence. However, kin selection in plants is still controversial. First, many studies documenting a plastic response to neighbour relatedness do not estimate fitness consequences of the individual that responds, and when estimated, fitness of individuals grown in competition with kin did not necessarily exceed that of individuals grown in non-kin groups. Although higher fitness in kin groups could be consistent with kin selection, this could also arise from mechanisms like asymmetric competition in the non-kin groups. Here we outline the main challenges for studying kin selection in plants taking genetic variation for competitive ability into account. We emphasize the need to measure inclusive fitness in order to assess whether kin selection occurs, and show under which circumstances kin selected responses can be expected. We also illustrate why direct fitness estimates of a focal plant, and group fitness estimates are not suitable for documenting kin selection. Importantly, natural selection occurs at the individual level and it is the inclusive fitness of an individual plant – not the mean fitness of the group – that can capture if a differential response to neighbour relatedness is favoured by kin selection.

Aim Biodiversity dynamics comprise evolutionary and ecological changes on multiple temporal scales from millions of years to decades, but they are often interpreted within a single time frame. Planktonic foraminifera communities offer a unique opportunity for analysing the dynamics of marine biodiversity over different temporal scales. Our study aims to provide a baseline for assessments of biodiversity patterns over multiple time-scales, which is urgently needed to interpret biodiversity responses to increasing anthropogenic pressure. Location Global (26 sites). Time period Five time-scales: multi-million-year (0-7 Myr), million-year (0-0.5 Myr), multi-millennial (0-15 thousand years), millennial (0-1,100 years) and decadal (0-32 years). Major taxa studied Planktonic foraminifera. Methods We analysed community composition of planktonic foraminifera at five time-scales, combining measures of standing diversity (richness and effective number of species, ENS) with measures of temporal community turnover (presence-absence-based, dominance-based). Observed biodiversity patterns were compared with the outcome of a neutral model to separate the effects of sampling resolution (the highest in the shortest time series) from biological responses. Results Richness and ENS decreased from multi-million-year to millennial time-scales, but higher standing diversity was observed on the decadal scale. As predicted by the neutral model, turnover in species identity and dominance was strongest at the multi-million-year time-scale and decreased towards the millennial scale. However, contrary to the model predictions, modern time series show rapid decadal variation in the dominance structure of foraminifera communities, which is of comparable magnitude as over much longer time periods. Community turnover was significantly correlated with global temperature change, but not on the shortest time-scale. Main conclusions Biodiversity patterns can be to some degree predicted from the scaling effects related to different durations of time series, but changes in the dominance structure observed over the last few decades reach higher magnitude, probably forced by anthropogenic effects, than those observed over much longer durations.

The understorey harbours a substantial part of vascular plant diversity in temperate forests and plays an important functional role, affecting ecosystem processes such as nutrient cycling and overstorey regeneration. Global change, however, is putting these understorey communities on trajectories of change, potentially altering and reducing their functioning in the future. Developing mitigation strategies to safeguard the diversity and functioning of temperate forests in the future is challenging and requires improved predictive capacity. Process-based models that predict understorey community composition over time, based on first principles of ecology, have the potential to guide mitigation endeavours but such approaches are rare. Here, we review fourteen understorey modelling approaches that have been proposed during the last three decades. We evaluate their inclusion of mechanisms that are required to predict the impact of global change on understorey communities. We conclude that none of the currently existing models fully accounts for all processes that we deem important based on empirical and experimental evidence. Based on this review, we contend new models are needed to project the complex impacts of global change on forest understoreys. Plant functional traits should be central to such future model developments, as they drive community assembly processes and provide valuable information on the functioning of the understorey. Given the important role of the overstorey, a coupling of understorey models to overstorey models will be essential to predict the impact of global change on understorey composition and structure, and how it will affect the functioning of temperate forests in the future.

International audience; Spatial heterogeneity plays a crucial role in the coexistence of species. Despite recogni- tion of the importance of self-organization in creating environmental heterogeneity in otherwise uni- form landscapes, the effects of such self-organized pattern formation in promoting coexistence through facilitation are still unknown. In this study, we investigated the effects of pattern formation on species interactions and community spatial structure in ecosystems with limited underlying envi- ronmental heterogeneity, using self-organized patchiness of the aquatic macrophyte Callitriche platy- carpa in streams as a model system. Our theoretical model predicted that pattern formation in aquatic vegetation – due to feedback interactions between plant growth, water flow and sedimentation pro- cesses – could promote species coexistence, by creating heterogeneous flow conditions inside and around the plant patches. The spatial plant patterns predicted by our model agreed with field observa- tions at the reach scale in naturally vegetated rivers, where we found a significant spatial aggregation of two macrophyte species around C. platycarpa. Field transplantation experiments showed that C. platycarpa had a positive effect on the growth of both beneficiary species, and the intensity of this facilitative effect was correlated with the heterogeneous hydrodynamic conditions created within and around C. platycarpa patches. Our results emphasize the importance of self-organized patchiness in promoting species coexistence by creating a landscape of facilitation, where new niches and facilitative effects arise in different locations. Understanding the interplay between competition and facilitation is therefore essential for successful management of biodiversity in many ecosystems.

Suboptimal environmental conditions are ubiquitous in nature and commonly drive the outcome of biological interactions in community processes. Despite the importance of biological interactions for community processes, knowledge on how species interactions are affected by a limiting resource, for example, low food availability, remains limited. Here, we tested whether variation in food supply causes nonadditive consumption patterns, using the macroinvertebrate community of intertidal sandy beaches as a model system. We quantified isotopically labeled diatom consumption by three macroinvertebrate species (Bathyporeia pilosa, Haustorius arenarius, and Scolelepis squamata) kept in mesocosms in either monoculture or a three‐species community at a range of diatom densities. Our results show that B. pilosa was the most successful competitor in terms of consumption at both high and low diatom density, while H. arenarius and especially S. squamata consumed less in a community than in their respective monocultures. Nonadditive effects on consumption in this macroinvertebrate community were present and larger than mere additive effects, and similar across diatom densities. The underlying species interactions, however, did change with diatom density. Complementarity effects related to niche‐partitioning were the main driver of the net diversity effect on consumption, with a slightly increasing contribution of selection effects related to competition with decreasing diatom density. For the first time, we showed that nonadditive effects of consumption are independent of food availability in a macroinvertebrate community. This suggests that, in communities with functionally different, and thus complementary, species, nonadditive effects can arise even when food availability is low. Hence, at a range of environmental conditions, species interactions hold important potential to alter ecosystem functioning.

The succession-driven reed bed habitat hosts a unique flora and fauna including several endangered invertebrate species. Reed beds can be managed through commercial winter harvest, with implications for reed bed conservation. However, the effects of winter harvest on the invertebrate community are not well understood and vary across studies and taxonomic levels. The aim of this study was to investigate the effects of reed harvest on invertebrate communities. Ground-dwelling and aerial invertebrates were continuously sampled for 10 weeks in the largest coherent reed bed of Scandinavia in order to assess how time since last reed harvest (0, 3, and 25years) influences invertebrate biomass, biodiversity and community structure across taxonomic levels. Biomass was measured and all specimens were sorted to order level, and Coleoptera was even sorted to species level. The invertebrate community showed distinct compositional differences across the three reed bed ages. Furthermore, biomass of both aerial and ground-dwelling invertebrates was highest in the age-0 reed bed and lowest in the age-25 reed bed. Generally, biodiversity showed an opposite trend with the highest richness and diversity in the age-25 reed bed. We conclude that it is possible to ensure high insect biomass and diversity by creating a mosaic of reed bed of different ages through small-scale harvest in the largest coherent reed bed in Scandinavia. The youngest red beds support a high invertebrate biomass whereas the oldest reed beds support a high biodiversity. Collectively, this elevate our understanding of reed harvest and the effects it has on the invertebrate communities, and might aid in future reed bed management and restoration.

Aim The number of studies investigating the nestedness and turnover components of beta diversity has increased substantially, but our general understanding of the drivers of turnover and nestedness remains elusive. Here, we examined the effects of species traits, spatial extent, latitude and ecosystem type on the nestedness and turnover components of beta diversity. Location Global. Time period 1968–2017. Major taxa studied From bacteria to mammals. Methods From the 99 studies that partition total beta diversity into its turnover and nestedness components, we assembled 269 and 259 data points for the pairwise and multiple site beta-diversity metrics, respectively. Our data covered a broad variation in species dispersal type, body size and trophic position. The data were from freshwater, marine and terrestrial realms, and encompassed geographical areas from the tropics to near polar regions. We used linear modelling as a meta-regression tool to analyse the data. Results Pairwise turnover, multiple site turnover and total beta diversity all decreased significantly with latitude. In contrast, multiple site nestedness showed a positive relationship with latitude. Beta-diversity components did not generally differ among the realms. The turnover component and total beta diversity increased with spatial extent, whereas nestedness was scale invariant for pairwise metrics. Multiple site beta-diversity components did not vary with spatial extent. Surprisingly, passively dispersed organisms had lower turnover and total beta diversity than flying organisms. Body size showed a relatively weak relationship with beta diversity but had important interactions with trophic position, thus also affecting beta diversity via interactive effects. Producers had significantly higher average pairwise turnover and total beta diversity than carnivores. Main conclusions The present results provide evidence that species turnover, being consistently the larger component of total beta diversity, and nestedness are related to the latitude of the study area and intrinsic organismal features. We showed that two beta-diversity components had generally opposing patterns with regard to latitude. We highlight that beta-diversity partition may give additional insights into the underlying causes of spatial variability in biotic communities compared with total beta diversity alone.

The organization of ecological communities along local environmental gradients provides important information about how such communities may respond to environmental change. In the Arctic, the importance of gradients in shrub cover and soil moisture for non-marine arthropod communities has been clearly demonstrated. By replicating studies along shrub and moisture gradients at multiple elevations and using space-for-time substitution, it is possible to examine how arthropod communities may respond to future environmental change. We collected and identified 4640 adult specimens of spiders and beetles near Narsarsuaq, South Greenland between 8 July and 25 August, 2014 from 112 pitfall traps. The traps were arranged in eight plots covering local gradients in either soil moisture or tall shrub dominance at both low and high elevation. Multivariate generalized linear models revealed that community composition was significantly related to shrub height and soil moisture, and that this relationship varied between low and high elevation. Among the 46 species we found, more species were unique to the high elevation plots than to the low elevation plots, a finding that was most pronounced for spiders in plots along soil moisture gradients. Indicator species analysis corroborated earlier findings of the indicator value of specific species in Greenland and suggested that beetles may serve as better indicators of specific habitats than spiders. The location of plots along local environmental gradients allowed us to detect fine-scale variation in arthropod communities. Together, our results suggest that Arctic arthropod community responses to environmental change may differ among low and high elevation sites.

There has been considerable focus on the impacts of environmental change on ecosystem function arising from changes in species richness. However, environmental change may affect ecosystem function without affecting richness, most notably by affecting population densities and community composition. Using a theoretical model, we find that, despite invariant richness, (1) small environmental effects may already lead to a collapse of function; (2) competitive strength may be a less important determinant of ecosystem function change than the selectivity of the environmental change driver and (3) effects on ecosystem function increase when effects on composition are larger. We also present a complementary statistical analysis of 13 data sets of phytoplankton and periphyton communities exposed to chemical stressors and show that effects on primary production under invariant richness ranged from -75% to +10%. We conclude that environmental protection goals relying on measures of richness could underestimate ecological impacts of environmental change. ISSN:1461-023X ISSN:1461-0248

International audience; This article explores the functional diversity and redundancy in a bacterial metacommunity constituted of three habitats (sediment, water column and fish gut) in a coastal lagoon under anthropogenic pressure. Comprehensive functional gene arrays covering a wide range of ecological processes and stress resistance genes to estimate the functional potential of bacterial communities were used. Then, diversity partitioning was used to characterize functional diversity and redundancy within (), between () and across () habitats. It was showed that all local communities exhibit a highly diversified potential for the realization of key ecological processes and resistance to various environmental conditions, supporting the growing evidence that macro-organisms microbiomes harbour a high functional potential and are integral components of functional gene dynamics in aquatic bacterial metacommunities. Several levels of functional redundancy at different scales of the bacterial metacommunity were observed (within local communities, within habitats and at the metacommunity level). The results suggested a high potential for the realization of spatial ecological insurance within this ecosystem, that is, the functional compensation among microorganisms for the realization and maintenance of key ecological processes, within and across habitats. Finally, the role of macro-organisms as dispersal vectors of microbes and their potential influence on marine metacommunity dynamics were discussed.; HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Based on concerns that useful weed diversity in agroecosystems as well as associated traditional knowledge may be declining due to agricultural intensification and indiscriminate eradication of weeds, we studied weed diversity and use by local ethnic groups in tea plantations in northern Thailand under different agricultural intensities and landscape complexities, namely agroforestry, organic, and Good Agricultural Practice (GAP) based conventional system. In each system, we sampled five tea plantations using belt-transects of 25 m(2). Use data were collected through interviews with specialist informants. We recorded 214 weed species (gamma-diversity) of which 66 were useful. Agroforestry system had the highest alpha- and beta-weed diversity, suggesting that the low agricultural intensity and high landscape complexity in this system is associated with higher weed diversity in tea plantations. The common weed species were clearly different in the three systems and only a small fraction (22 species) of widespread weeds was shared among them, resulting in low weed similarity between systems. The 66 useful species of weeds were mostly for food and medicine. Uses of some weeds were shared between systems. Many of the useful weeds are invasive species, suggesting that they are prevalent and inexpensive plant resources for rural people and could represent alternative resources in the future. Because the occurrence of invasive weeds may affect the natural habitats of the native flora, integrating the exploitation of weeds into weed management strategies may reduce the weed population while sustaining agrobiodiversity and conserving associated traditional knowledge in the long term.

Here we build on the manifesto ‘World Scientists’ Warning to Humanity, issued by the Alliance of World Scientists. As a group of conservation biologists deeply concerned about the decline of insect populations, we here review what we know about the drivers of insect extinctions, their consequences, and how extinctions can negatively impact humanity. We are causing insect extinctions by driving habitat loss, degradation, and fragmentation, use of polluting and harmful substances, the spread of invasive species, global climate change, direct overexploitation, and co-extinction of species dependent on other species. With insect extinctions, we lose much more than species. We lose abundance and biomass of insects, diversity across space and time with consequent homogenization, large parts of the tree of life, unique ecological functions and traits, and fundamental parts of extensive networks of biotic interactions. Such losses lead to the decline of key ecosystem services on which humanity depends. From pollination and decomposition, to being resources for new medicines, habitat quality indication and many others, insects provide essential and irreplaceable services. We appeal for urgent action to close key knowledge gaps and curb insect extinctions. An investment in research programs that generate local, regional and global strategies that counter this trend is essential. Solutions are available and implementable, but urgent action is needed now to match our intentions.

Tropical montane forests are important reservoirs of carbon and biodiversity and have a central role in the hydrological cycle. They are, however, very fragmented and degraded, leaving isolated remnants across the landscape. These montane forest remnants have considerable differences in forest structure, depending on factors such as tree species composition and degree of forest degradation. Our objectives were (1) to analyse the reliability of airborne laser scanning (ALS) in modelling forest structural heterogeneity, as described by the Gini coefficient (GC) of tree size inequality; (2) to determine whether models are improved by including tree species-sensitive spectral-temporal metrics from the Landsat time series (LTS); and (3) to evaluate differences between three forest remnants and different forest types using the resulting maps of predicted GC. The study area was situated in Taita Hills, Kenya, where indigenous montane forests have been partly replaced by single-species plantations. The data included field measurements from 85 sample plots and two ALS data sets with different pulse densities (9.6 and 3.1 pulses m(-2)). GC was modeled using beta regression. We found that GC was predicted more accurately by the ALS data set with a higher point density (a cross-validated relative root mean squared error (rRMSE(CV)) 13.9%) compared to ALS data set with lower point density (rRMSE(CV) 15.1%). Furthermore, important synergies exist between ALS and LTS metrics. When combining ALS and LTS metrics, rRMSE(CV) was improved to 12.5% and 13.0%, respectively. Therefore, if the LTS metrics are included in models, ALS data with lower pulse density are sufficient to yield similar accuracy to more expensive, higher pulse density data acquired from the lower altitude. In Ngangao and Yale, forest canopy has multiple layers of variable tree sizes, whereas elfin forests in Vuria are of more equal tree size, and the GC value ranges of the indigenous forests are 0.42-0.71, 0.20-0.74, and 0.17-0.76, respectively. The single-species plantations of cypress and pine showed lower values of GC than indigenous forests located in the same remnants in Yale, whereas Eucalyptus plantations showed GC values more similar to the indigenous forests. These results show the usefulness of GC maps for identifying and separating forest types as well as for assessing their distinctive ecologies.

Associational resistance theory predicts that insect herbivory decreases with increasing tree diversity in forest ecosystems. However, the generality of this effect and its underlying mechanisms are still debated, particularly since evidence has accumulated that climate may influence the direction and strength of the relationship between diversity and herbivory.We quantified insect leaf herbivory and leaf chemical defences (phenolic compounds) of silver birch Betula pendula in pure and mixed plots with different tree species composition across 12 tree diversity experiments in different climates. We investigated whether the effects of neighbouring tree species diversity on insect herbivory in birch, that is, associational effects, were dependent on the climatic context, and whether neighbour-induced changes in birch chemical defences were involved in associational resistance to insect herbivory.We showed that herbivory on birch decreased with tree species richness (i.e. associational resistance) in colder environments but that this relationship faded as mean annual temperature increased.Birch leaf chemical defences increased with tree species richness but decreased with the phylogenetic distinctiveness of birch from its neighbours, particularly in warmer and more humid environments.Herbivory was negatively correlated with leaf chemical defences, particularly when birch was associated with closely related species. The interactive effect of tree diversity and climate on herbivory was partially mediated by changes in leaf chemical defences.Our findings confirm that tree species diversity can modify the leaf chemistry of a focal species, hence its quality for herbivores. They further stress that such neighbour-induced changes are dependent on climate and that tree diversity effects on insect herbivory are partially mediated by these neighbour-induced changes in chemical defences. ispartof: FUNCTIONAL ECOLOGY vol:35 issue:1 pages:67-81 ispartof: location:England status: published

In 2015, we collected more than 60 000 scavenging amphipod specimens during two expeditions to the Clarion-Clipperton fracture zone (CCZ) in the Northeast (NE) Pacific and to the DISturbance and re-COLonisation (DisCOL) experimental area (DEA), a simulated mining impact disturbance proxy in the Peru Basin in the Southeast (SE) Pacific. Here, we compare biodiversity patterns of the larger specimens (> 15 mm) within and between these two oceanic basins. Eight scavenging amphipod species are shared between these two areas, thus indicating connectivity. Overall diversity was lower in the DEA (Simpson index, D = 0.62), when compared to the CCZ (D = 0.73), and particularly low at the disturbance site in the DEA and the site geographically closest to it. Local differences within each basin were observed too. The community compositions of the two basins differ, as evidenced by a non-metric dimensional scaling (NMDS) analysis of beta biodiversity. Finally, a single species, Abyssorchomene gerulicorbis (Schulenberger and Barnard, 1976), dominates the DEA with 60% of all individuals. This research has been supported by the JPI-Oceans project "Mining Impact" (BELSPO grant no. BR/15/MA/JPI-DEEPSEA2). Patel, T (corresponding author), Univ Ghent, Dept Biol, KL Ledeganckstr 35, B-9000 Ghent, Belgium. tpatel@naturalsciences.be

The study of biodiversity started as a single unified field that spanned both ecology and evolution and both macro and micro phenomena. But over the 20th century, major trends drove ecology and evolution apart and pushed an emphasis towards the micro perspective in both disciplines. Macroecology and macroevolution re-emerged as self-consciously distinct fields in the 1970s and 1980s, but they remain largely separated from each other. Here, we argue that despite the challenges, it is worth working to combine macroecology and macroevolution. We present 25 fundamental questions about biodiversity that are answerable only with a mixture of the views and tools of both macroecology and macroevolution., This paper is a joint effort of the working group sEcoEvo, kindly supported by sDiv, the Synthesis Centre of the German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐Leipzig, funded by the German Research Foundation (FZT 118). Brian McGill acknowledges US Department of Agriculture Hatch grant to Maine Agricultural and Forestry Experimental Station #1011538 and National Science Foundation Advances in Biological Infrastructure grant #1660000.

Leaf and root systems are known to show a high degree of developmental plasticity in response to the local environment. However, few studies have investigated simultaneously the leaf and root traits as affected by competition and phosphorus (P) fertilization, especially in connection with the primary succession. We investigated morphological and physiological responses to different competition treatments (infra- vs. interspecific competition) and P regimes in seedlings of Abies fabri and Picea brachytyla, collected from the late succession stage Hailuogou glacier retreat area. A. fabri had a greater total chlorophyll content and specific leaf area (SLA), higher leaf nitrogen (N) and P concentrations, as well as a higher water use efficiency (assessed by the carbon isotope composition, delta C-13) and N absorption relative to P. brachytyla under P fertilization conditions, and its total biomass responded more strongly to P fertilization, especially under interspecific competition. P fertilization decreased the specific root length (SRL) and ectomycorrhizal infection in both species and specific root tip density in P. brachytyla but it had no effect on the average root diameter. We concluded that similar changes in root characteristics, but the superior performance of above-ground traits in A. fabri in response to P availability, especially under competition, explain the greater competitive capacity of A. fabri at final stages of succession. These findings highlight the influence of soil nutrition availability and competition on the functional traits of plants and contribute to the understanding of the role of relative modifications in leaf and root traits during succession.

Ethiopian shade coffee plantations are well documented to be bird-friendly and act as refuges for disappearing tree species. The extent to which these plantations support mammal conservation, as well as mammal sensitivity to coffee intensification, remain little studied. We studied the distribution and diversity of mammals under three coffee management systems of differing intensities (i.e., semi-forest, semi-plantation, and plantation) and in nearby natural forests in Belete-Gera Forest Priority Area, southwestern Ethiopia. We detected mammals using 30 infrared camera traps at 90 stations for a total of 4142 camera days. We used the Shannon-Wiener diversity index for diversity analysis, generalized linear mixed model for comparison of independent detection, and non-metric multidimensional scaling to show the mammalian community composition. We recorded 8815 digital videos and a total of 23 mammal species. The overall species richness, diversity, and detection of mammals did not differ between the two traditional shade coffee management systems and the natural forest but was lower in the plantation coffee system. The mammal community composition also shows variation in resilience to coffee management intensity, with primates appearing to be generally more tolerant to management intensification. We ultimately show that traditionally managed Ethiopian shade coffee farms shelter diverse mammal communities, comparable to those in nearby natural forests. Therefore, supporting traditional coffee management practices and certifying them as mammal-friendly should be implemented as strategies for the conservation of mammals, as natural forests continue to decline in Ethiopia.

00000 ăWOS:000388003500012; International audience; The ecological process of community assembly is described as the succession of three phases: colonization, regulation and segregation. Early colonization remains the least studied and quantified phase of assembly. In order to fill this gap, an approach combining in situ experiments and modelling was proposed to study colonization by a benthic macrofauna community in open microcosms containing a single, non-limiting resource. The experiment was three months long. A total of 51 taxa were observed in the microcosms, but data analyses of the species composition and abundances revealed that five species, Capitella spp., Gammaropsis maculata, Erichtionus punctatus, Nereiphylla paretti and Harmothoe mariannae, explained most of the observed variation in the assembly process. The population dynamics of these species were simulated taking into account functional traits that govern individual interactions. The dynamic model simulated a demographic stochasticity due to low population densities that result from the small size of the experimental microcosms. Using this combined approach of experiments and modelling, we showed that predation interactions alone can account for the abundances and species composition of primary consumers during the transient phase of early colonization.

Slow-downs in lineage accumulation in phylogenies suggest that speciation rates decline as diversity increases. Likelihood methods have been developed to detect such diversity-dependence. However, a thorough test of whether such approaches correctly infer diversity-dependence is lacking.Here we simulate phylogenetic branching under linear negative diversity-dependent and diversity-independent models and estimate from the simulated phylogenies the maximum likelihood parameters for three different conditionings – on survival of the birth-death process given the crown age, on tree size (N), and on tree size given the crown age. We report the accuracy of recovering the simulation parameters and the reliability of the model selection based on the χ2 likelihood ratio test.Parameter estimate accuracyConditioning on survival given the crown age yields a severe bias of the carrying capacity K toward N, and an upward bias of the speciation rate, particularly in clades where diversity-dependent feedbacks are still weak (N « K). Conditioning on N yields an overestimate of K and an underestimate of speciation rate, particularly when saturation has been reached. Dual conditioning yields relatively unbiased parameter estimates on average, but the deviation from the true value for any single estimate may be large.Model selection reliabilityThe frequency of incorrectly rejecting a diversity-independent model when the simulation was diversity-independent (Type I error) differs substantially from the significance level α used in the likelihood ratio test, rendering the likelihood ratio test inappropriate. The frequency of correctly rejecting the diversity-independent model when the simulation was diversity-dependent (power) is larger when the clade is closer to equilibrium, and for conditioning on crown age.We conclude that conditioning on crown age has the best statistical properties overall, but caution that parameter estimates may be biased. To assess parameter uncertainty in future studies of diversity-dependence on real data, we recommend parametric bootstrapping, examination of the likelihood surface and comparison of estimates across the types of conditioning. To assess model selection reliability we discourage the use of the χ2 likelihood ratio test or AIC (which are equivalent in this case), but recommend a likelihood ratio test based on parametric bootstrap. We illustrate this method for the diversification of Dendroica warblers.

To understand and manage ecosystem complexity, it is important to determine the relationships between soil characteristics, human activities, and biodiversity. This study analyzes the relationships between vegetation, soil, and man-made damage with regards to land use change in the Fereydan region, Iran. Soil physical properties such as sand and silt content, clay, saturated soil&rsquo, s moisture content, and gravel percentage as well as chemical properties such as lime content, pH, electro conductivity (EC), and organic matter content were measured. In order to trace these variables, the principle component analysis (PCA) was applied. The study area was divided into three states of conditions, i.e., good condition rangelands, poor condition rangelands, and abandoned rain-fed area. Based on the results there was a significant difference between species diversity in good condition rangelands compared with two other sites. The results further revealed that among soil chemical and physical characteristics, only soil organic matter had a significant difference between different rangeland sites. According to the results, the rangelands with good conditions had the highest amount of organic matter (1.43&ndash, 1.50%) compared with two other studied rangelands (poor conditions: 1.02&ndash, 1.09%, abandoned rain-fed: 1.2&ndash, 1.46%). The most influential factor on the species diversity index was the distance to village parameter that revealed the important role of humans in degrading rangelands and reducing species diversity.