Existing general definitions of beta diversity often produce a beta with a hidden dependence on alpha. Such a beta cannot be used to compare regions that differ in alpha diversity. To avoid ...misinterpretation, existing definitions of alpha and beta must be replaced by a definition that partitions diversity into independent alpha and beta components. Such a unique definition is derived here. When these new alpha and beta components are transformed into their numbers equivalents (effective numbers of elements), Whittaker's multiplicative law (alpha × beta = gamma) is necessarily true for all indices. The new beta gives the effective number of distinct communities. The most popular similarity and overlap measures of ecology (Jaccard, Sorensen, Horn, and Morisita-Horn indices) are monotonic transformations of the new beta diversity. Shannon measures follow deductively from this formalism and do not need to be borrowed from information theory; they are shown to be the only standard diversity measures which can be decomposed into meaningful independent alpha and beta components when community weights are unequal.
1. The successional dynamics of forests—from canopy openings to regeneration, maturation, and decay—influence the amount and heterogeneity of resources available for forest-dwelling organisms. ...Conservation has largely focused only on selected stages of forest succession (e.g., late-seral stages). However, to develop comprehensive conservation strategies and to understand the impact of forest management on biodiversity, a quantitative understanding of how different trophic groups vary over the course of succession is needed. 2. We classified mixed mountain forests in Central Europe into nine successional stages using airborne LiDAR. We analysed α- and β-diversity of six trophic groups encompassing approximately 3,000 species from three kingdoms. We quantified the effect of successional stage on the number of species with and without controlling for species abundances and tested whether the data fit the more-individuals hypothesis or the habitat heterogeneity hypothesis. Furthermore, we analysed the similarity of assemblages along successional development. 3. The abundance of producers, first-order consumers, and saprotrophic species showed a U-shaped response to forest succession. The number of species of producer and consumer groups generally followed this U-shaped pattern. In contrast to our expectation, the number of saprotrophic species did not change along succession. When we controlled for the effect of abundance, the number of producer and saproxylic beetle species increased linearly with forest succession, whereas the U-shaped response of the number of consumer species persisted. The analysis of assemblages indicated a large contribution of succession-mediated β-diversity to regional γ-diversity. 4. Synthesis and applications. Depending on the species group, our data supported both the more-individuals hypothesis and the habitat heterogeneity hypothesis. Our results highlight the strong influence of forest succession on biodiversity and underline the importance of controlling for successional dynamics when assessing successional stages with highest diversity (early and late successional stages) are currently strongly underrepresented in the forests of Central Europe. We thus recommend that conservation strategies aim at a more balanced representation of all successional stages.
Semi‐natural features among farmland have a key role in maintaining wildlife in rural landscapes. Practical conservation requires knowledge of which combinations of features are of greatest value and ...whether this differs among faunal groups. We used a ‘landscape’ approach to investigate the relative importance to birds and insects (bees, flies, wasps) of combinations of three wooded features typical of farmland in south‐eastern Australia: scattered trees, wooded roadsides and wooded streamside vegetation.
We selected 44 landscapes (1 km diameter) representing four combinations: (a) landscapes with all three features present, (b) landscapes lacking scattered trees, (c) lacking wooded roadsides and (d) lacking wooded streamsides. We surveyed birds and selected insects, and compared mean alpha (α, site), beta (β, between site) and gamma (γ, landscape) diversity for each taxon between landscape types; and gamma (γ) diversity of bird species displaying breeding activity.
Mean α‐diversity of birds was reduced in landscapes lacking wooded roadsides or streams, relative to those with all three wooded features; while species differentiation (β‐diversity) increased in these landscapes. Loss of streamside vegetation had the greatest landscape‐scale impact, reducing γ‐diversity by ~33% for all land‐birds and ~50% for woodland birds. Bird breeding activity declined by ~50% in landscapes lacking wooded streamsides. In contrast, insects showed little response, except bees for which mean α‐diversity was greater in more open landscapes lacking scattered trees or wooded roadsides, compared with those containing all wooded features. This did not lead to differences in landscape‐level (γ) diversity.
Synthesis and applications. Birds and insects respond differently to combinations of semi‐natural features in rural landscapes, highlighting the need to better meet the requirements of multiple faunal groups in nature conservation activities. Wooded features, especially streamside vegetation, are critical for maintaining diversity and breeding activity of woodland birds. Given a general lack of knowledge of the insect fauna in some regions and varied results here, a prudent approach is to foster a diverse farmland mosaic comprising semi‐natural habitats together with floristically rich, modified features that provide temporally dynamic resources. These combined landscape features are important for faunal conservation, while also supporting farm productivity and ecosystem services.
Birds and insects respond differently to combinations of semi‐natural features in rural landscapes, highlighting the need to better meet the requirements of multiple faunal groups in nature conservation activities. Wooded features, especially streamside vegetation, are critical for maintaining diversity and breeding activity of woodland birds. Given a general lack of knowledge of the insect fauna in some regions and varied results here, a prudent approach is to foster a diverse farmland mosaic comprising semi‐natural habitats together with floristically rich, modified features that provide temporally dynamic resources. These combined landscape features are important for faunal conservation, while also supporting farm productivity and ecosystem services.
AIM: To define biome‐scale hotspots of phylogenetic and functional mammalian biodiversity (PD and FD, respectively) and compare them with ‘classical’ hotspots based on species richness (SR) alone. ...LOCATION: Global. METHODS: SR, PD and FD were computed for 782 terrestrial ecoregions using the distribution ranges of 4616 mammalian species. We used a set of comprehensive diversity indices unified by a recent framework incorporating the relative species coverage in each ecoregion. We built large‐scale multifaceted diversity–area relationships to rank ecoregions according to their levels of biodiversity while accounting for the effect of area on each facet of diversity. Finally we defined hotspots as the top‐ranked ecoregions. RESULTS: While ignoring relative species coverage led to a fairly good congruence between biome‐scale top ranked SR, PD and FD hotspots, ecoregions harbouring a rich and abundantly represented evolutionary history and FD did not match with the top‐ranked ecoregions defined by SR. More importantly PD and FD hotspots showed important spatial mismatches. We also found that FD and PD generally reached their maximum values faster than SR as a function of area. MAIN CONCLUSIONS: The fact that PD/FD reach their maximum value faster than SR could suggest that the two former facets might be less vulnerable to habitat loss than the latter. While this point is expected, it is the first time that it has been quantified at a global scale and should have important consequences for conservation. Incorporating relative species coverage into the delineation of multifaceted hotspots of diversity led to weak congruence between SR, PD and FD hotspots. This means that maximizing species number may fail to preserve those nodes (in the phylogenetic or functional tree) that are relatively abundant in the ecoregion. As a consequence it may be of prime importance to adopt a multifaceted biodiversity perspective to inform conservation strategies at a global scale.
Biodiversity‐ecosystem functioning experiments have established that species richness and composition are both important determinants of ecosystem function in an experimental context. Determining ...whether this result holds for real‐world ecosystem services has remained elusive, however, largely due to the lack of analytical methods appropriate for large‐scale, associational data. Here, we use a novel analytical approach, the Price equation, to partition the contribution to ecosystem services made by species richness, composition and abundance in four large‐scale data sets on crop pollination by native bees. We found that abundance fluctuations of dominant species drove ecosystem service delivery, whereas richness changes were relatively unimportant because they primarily involved rare species that contributed little to function. Thus, the mechanism behind our results was the skewed species‐abundance distribution. Our finding that a few common species, not species richness, drive ecosystem service delivery could have broad generality given the ubiquity of skewed species‐abundance distributions in nature.
Species enter and persist in local communities because of their ecological fit to local conditions, and recently, ecologists have moved from measuring diversity as species richness and evenness, to ...using measures that reflect species ecological differences. There are two principal approaches for quantifying species ecological differences: functional (trait‐based) and phylogenetic pairwise distances between species. Both approaches have produced new ecological insights, yet at the same time methodological issues and assumptions limit them. Traits and phylogeny may provide different, and perhaps complementary, information about species' differences. To adequately test assembly hypotheses, a framework integrating the information provided by traits and phylogenies is required. We propose an intuitive measure for combining functional and phylogenetic pairwise distances, which provides a useful way to assess how functional and phylogenetic distances contribute to understanding patterns of community assembly. Here, we show that both traits and phylogeny inform community assembly patterns in alpine plant communities across an elevation gradient, because they represent complementary information. Differences in historical selection pressures have produced variation in the strength of the trait‐phylogeny correlation, and as such, integrating traits and phylogeny can enhance the ability to detect assembly patterns across habitats or environmental gradients.
Biodiversity encompasses multiple attributes such as the richness and abundance of species (taxonomic diversity), the presence of different evolutionary lineages (phylogenetic diversity), and the ...variety of growth forms and resource use strategies (functional diversity). These biodiversity attributes do not necessarily relate to each other and may have contrasting effects on ecosystem functioning. However, how they simultaneously influence the provision of multiple ecosystem functions related to carbon, nitrogen, and phosphorus cycling (multifunctionality) remains unknown. We evaluated the effects of the taxonomic, phylogenetic, and functional attributes of dominant (mass ratio effects) and subordinate (richness effect) plant species on the multifunctionality of 123 drylands from six continents. Our results highlight the importance of the phylogenetic and functional attributes of subordinate species as key drivers of multifunctionality. In addition to a higher taxonomic richness, we found that simultaneously increasing the richness of early diverging lineages and the functional redundancy between species increased multi-functionality. In contrast, the richness of most recent evolutionary lineages and the functional and phylogenetic attributes of dominant plant species (mass ratio effects) were weakly correlated with multifunctionality. However, they were important drivers of individual nutrient cycles. By identifying which biodiversity attributes contribute themost tomultifunctionality, our results can guide restoration efforts aiming to maximize either multifunctionality or particular nutrient cycles, a critical step to combat dryland desertification worldwide.
Assessing the level of diversity in plant communities from field‐based data is difficult for a number of practical reasons: (1) establishing the number of sampling units to be investigated can be ...difficult; (2) the choice of sample design can impact on results; and (3) defining the population of concern can be challenging. Satellite remote sensing (SRS) is one of the most cost‐effective approaches to identify biodiversity hotspots and predict changes in species composition. This is because, in contrast to field‐based methods, it allows for complete spatial coverages of the Earth's surface under study over a short period of time. Furthermore, SRS provides repeated measures, thus making it possible to study temporal changes in biodiversity. Here, we provide a concise review of the potential of satellites to help track changes in plant species diversity, and provide, for the first time, an overview of the potential pitfalls associated with the misuse of satellite imagery to predict species diversity. Our work shows that, while the assessment of alpha‐diversity is relatively straightforward, calculation of beta‐diversity (variation in species composition between adjacent locations) is challenging, making it difficult to reliably estimate gamma‐diversity (total diversity at the landscape or regional level). We conclude that an increased collaboration between the remote sensing and biodiversity communities is needed in order to properly address future challenges and developments.
Assessing the level of diversity in plant communities from field‐based data is difficult for a number of practical reasons: (1) establishing the number of sampling units to be investigated can be difficult; (2) the choice of sample design can affect results; and (3) defining the population of concern can be challenging. Satellite remote sensing (SRS) is one of the most cost‐effective approaches to identify biodiversity hotspots and predict changes in species composition. This is because, in contrast to field‐based methods, it allows for complete spatial coverage of the Earth's surface under study over a short period of time. Furthermore, SRS provides repeated measures, thus making it possible to study temporal changes in biodiversity. Here we provide a concise review of the potential of remote sensing to help track changes in plant species diversity, and provide, for the first time, an overview of the potential pitfalls associated with the misuse of SRS to predict species diversity. Figure reproduced from: Feret, J.‐B., and G. P. Asner. 2014. Mapping tropical forest canopy diversity using high‐delity imaging spectroscopy. Ecol. Appl. 24:1289–1296. ‐ with kind permission from the Ecological Society of America.
Organizational diversity has become a topic of interest for practitioners and academics alike. This book explores how diversity in organizations is, and can be researched, providing readers with ...insights into the potential research designs for studies in contemporary organizations.
This includes paying attention to methods but also to the role of the researcher and research bodies in the field, to their potential as activists as well as to the theoretical question of standpoints in researching organizational diversity. Chapters also consider the diversity of research participants, inclusive research, and intersectionality. All contributors are experts in diversity research, and in their contributions, they reflect upon the appropriate methods for the specific type of diversity research they conduct, noting strengths and weaknesses and illustrating their arguments with practical examples from their work.
This handbook will be of great value to academics, students, researchers, practitioners, and professionals with an interest in broadening their understanding of how to research organizational diversity in contemporary organizations or seeking to develop their awareness of diversity when researching management and organization, more generally.
Agricultural intensification is a leading cause of global biodiversity loss, which can reduce the provisioning of ecosystem services in managed ecosystems. Organic farming and plant diversification ...are farm management schemes that may mitigate potential ecological harm by increasing species richness and boosting related ecosystem services to agroecosystems. What remains unclear is the extent to which farm management schemes affect biodiversity components other than species richness, and whether impacts differ across spatial scales and landscape contexts. Using a global metadataset, we quantified the effects of organic farming and plant diversification on abundance, local diversity (communities within fields), and regional diversity (communities across fields) of arthropod pollinators, predators, herbivores, and detritivores. Both organic farming and higher in‐field plant diversity enhanced arthropod abundance, particularly for rare taxa. This resulted in increased richness but decreased evenness. While these responses were stronger at local relative to regional scales, richness and abundance increased at both scales, and richness on farms embedded in complex relative to simple landscapes. Overall, both organic farming and in‐field plant diversification exerted the strongest effects on pollinators and predators, suggesting these management schemes can facilitate ecosystem service providers without augmenting herbivore (pest) populations. Our results suggest that organic farming and plant diversification promote diverse arthropod metacommunities that may provide temporal and spatial stability of ecosystem service provisioning. Conserving diverse plant and arthropod communities in farming systems therefore requires sustainable practices that operate both within fields and across landscapes.
Organic farming and on‐farm plant diversification can reduce biodiversity loss and boost‐related ecosystem services like pollination and pest control. Using a global dataset, we found that both management schemes enhanced richness at local and regional scales, mainly by promoting rare taxa that are critical for ecosystem resilience. Positive effects were greatest for two groups of beneficial insects: pollinators and predators. We also found stronger impacts of farm management for fields embedded in complex landscapes.
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