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The successful movement of individuals is fundamental to life. Facilitating these movements by promoting ecological connectivity has become a central theme in ecology and conservation. Urban areas contain more than half of the world's human population, and their potential to support biodiversity and to connect their citizens to nature is increasingly recognized. Promoting ecological connectivity within these areas is essential to reaching this potential. However, our current understanding of ecological connectivity within urban areas appears limited., We reviewed the published scientific literature to assess the state-of-the-art of ecological connectivity research in urban areas, summarized trends in study attributes and highlighted knowledge gaps., We found 174 papers that investigated ecological connectivity within urban areas. These papers addressed either structural (48) or functional connectivity (111), and some addressed both (15), but contained substantial geographic and taxonomic biases. These papers rarely defined the aspect of connectivity they were investigating and objective descriptions of the local urban context were uncommon. Formulated hypotheses or a priori predictions were typically unstated and many papers used suboptimal study designs and methods., We suggest future studies explicitly consider and quantify the landscape within their analyses and make greater use of available and rapidly developing tools and methods for measuring functional connectivity (e.g. biotelemetry or landscape genetics). We also highlight the need for studies to clearly define how the terms ' urban' and ' connectivity' have been applied., Knowledge gaps in ecological connectivity in urban areas remain, partly because the field is still in its infancy and partly because we must better capitalize on the state-of-the-art technological and analytical techniques that are increasingly available. Well-designed studies that employed high-resolution data and powerful analytical techniques highlight our abilities to quantify ecological connectivity in urban areas. These studies are exemplary, setting the standards for future research to facilitate data-driven and evidence-based biodiversity-friendly infrastructure planning in urban areas. [ABSTRACT FROM AUTHOR]

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Information on tropical Asian vertebrates has traditionally been sparse, particularly when it comes to cryptic species inhabiting the dense forests of the region. Vertebrate populations are declining globally due to land‐use change and hunting, the latter frequently referred as "defaunation." This is especially true in tropical Asia where there is extensive land‐use change and high human densities. Robust monitoring requires that large volumes of vertebrate population data be made available for use by the scientific and applied communities. Camera traps have emerged as an effective, non‐invasive, widespread, and common approach to surveying vertebrates in their natural habitats. However, camera‐derived datasets remain scattered across a wide array of sources, including published scientific literature, gray literature, and unpublished works, making it challenging for researchers to harness the full potential of cameras for ecology, conservation, and management. In response, we collated and standardized observations from 239 camera trap studies conducted in tropical Asia. There were 278,260 independent records of 371 distinct species, comprising 232 mammals, 132 birds, and seven reptiles. The total trapping effort accumulated in this data paper consisted of 876,606 trap nights, distributed among Indonesia, Singapore, Malaysia, Bhutan, Thailand, Myanmar, Cambodia, Laos, Vietnam, Nepal, and far eastern India. The relatively standardized deployment methods in the region provide a consistent, reliable, and rich count data set relative to other large‐scale pressence‐only data sets, such as the Global Biodiversity Information Facility (GBIF) or citizen science repositories (e.g., iNaturalist), and is thus most similar to eBird. To facilitate the use of these data, we also provide mammalian species trait information and 13 environmental covariates calculated at three spatial scales around the camera survey centroids (within 10‐, 20‐, and 30‐km buffers). We will update the dataset to include broader coverage of temperate Asia and add newer surveys and covariates as they become available. This dataset unlocks immense opportunities for single‐species ecological or conservation studies as well as applied ecology, community ecology, and macroecology investigations. The data are fully available to the public for utilization and research. Please cite this data paper when utilizing the data. [ABSTRACT FROM AUTHOR]

Anthropogenic forcing caused the biodiversity loss and stability decline of communities. There is still controversy over whether the decline in biodiversity will lead to a decrease in community stability. The stability of biological communities is related to both biodiversity and structure, and this paper aims to reveal the human impacts on diatom communities' biodiversity and structure. We studied the richness, β‐diversity and network distance of diatom communities in Qinghai‐Xizang, Yunnan‐Sichuan and Lower Yangtze River Basin, China through empirical dataset and simulation method. The results showed that the diatoms richness in the Qinghai‐Xizang and the Yunnan‐Sichuan region was lower and the network distance was higher than that of the Lower Yangtze River Basin. β‐diversity in the Lower Yangtze River Basin was the lowest and the diatom network distance responds negatively to human population densities in China. The simulation showed that the network distance kept constant during random species loss, and declined while specialist species were lost or replaced by generalist species. The results suggested diatom communities' homogeneity and stability decline were associated with human activities. Human impacts may cause biodiversity loss targeted to specialist species or no biodiversity loss while generalist species replace those specialist species. This study showed that how diversity changes determined ecological stability depends on the type of species changes. [ABSTRACT FROM AUTHOR]

Summary: This paper provides a critical analysis of the development and current outcomes of Australia's first endorsed strategic assessment under the Environment Protection and Biodiversity Conservation Act 1999, namely, the Melbourne Strategic Assessment. It covers progress towards protection of a number of Nationally Significant Species and Ecological Communities – most notably, the native grassland communities immediately adjacent to Melbourne's Urban Growth Boundary. The Commonwealth approval to protect biodiversity and allow urban development was made in 2010 and it aimed to achieve its outcomes by 2020. These outcomes included providing new land for homes, for new transport corridors, and for conservation of biodiversity. Natural Temperate Grassland (4,667 ha), Grassy Eucalypt Woodland (709 ha) and seven other Matters of National Environmental Significance will be impacted. Mitigation for this is establishment of 15,000 ha of grassland reserves, 1,200 ha of grassy woodland reserves, over 4,000 ha of other land zoned for conservation and 300 ha of wetland restoration. We conclude that the Melbourne Strategic Assessment has been a success in terms of the elegance and comprehensiveness of the approach, in cooperation between the levels of government, in the economic benefits, and in some aspects of social engagement of the agreement. However, the achievement of environmental outcomes must be currently considered a failure due to poor implementation. This failure includes not meeting the agreed 10 year deadline for land acquisition and management, poor monitoring and protection of set‐aside areas, and in reporting. We offer suggestions for how these current shortcomings could be overcome. These align well with the recommendations of the review of the Environment Protection and Biodiversity Conservation Act 1999 (The independent statutory review of the Act in 2020) and include the establishment of the proposed Office of Compliance and Enforcement, the adoption of National Environmental Standards and the reforms regarding the role of Indigenous Australians in strategic assessments. If these were adopted, we conclude that the strategic assessment approach should be more widely used because of the more holistic approach and efficiencies that it envisages compared with site by site approaches. [ABSTRACT FROM AUTHOR]

Biodiversity, community ecology, global change, plant traits, plant-microbe interactions (b) Campanula scheuchzeri in the forefield of the Ödenwinkel glacier in Austria; this is one of the few plant species that occurs along the whole successional gradient, and thus became a model species in our laboratory to test successional processes. gl References 1 E-Vojtkó A, Junker RR, de Bello F, Götzenberger L. 2022. Keywords: biodiversity; community ecology; global change; plant traits; plant-microbe interactions EN biodiversity community ecology global change plant traits plant-microbe interactions 1634 1636 3 11/07/22 20221201 NES 221201 What inspired your interest in plant science?. [Extracted from the article]

Unprecedented rates of species extinctions have prompted extensive research into the consequences of biodiversity losses on ecosystem functioning. While aquatic species are most threatened, research with freshwater and marine model systems has lagged behind progress made in terrestrial environments. This editorial to a special feature summarizes the main outcomes of a conference aimed at setting the stage for exploring the potential of aquatic systems to assess the role of biodiversity in ecosystem functioning. This series of papers proposes fresh approaches to the study of biodiversity effects on ecosystem functioning, outlines a new way of analyzing experimental data, presents a model that considers scale as an important factor determining outcomes, explores the effects of multiple stressors on species richness and ecosystem processes, and develops a food-web perspective that relates ecosystem properties to biodiversity. An insightful synthesis of lessons learned from aquatic systems is premature at present, but the papers clearly demonstrate the role that marine and freshwater systems can play in resolving open questions. The implications go well beyond the biodiversity in, and functioning of, ecosystems shaped by free-flowing or standing water. [ABSTRACT FROM AUTHOR]

The unique aquatic Pontocaspian (PC) biota of the Black Sea Basin (BSB) is in decline. The lack of detailed knowledge on the status and trends of species, populations, and communities hampers a thorough risk assessment and precludes effective conservation. This paper reviews PC biodiversity trends in the BSB (Bulgaria, Romania, Moldova, Ukraine, and Russia) using endemic mollusks as a model group. We aim to assess changes in PC habitats, community structure, and species distribution over the past century and to identify direct anthropogenic threats. The presence/absence data of target mollusk species were assembled from literature, reports, and personal observations. Pontocaspian biodiversity trends in the northwestern BSB coastal regions were established by comparing 20th‐ and 21st‐century occurrences. The direct drivers of habitat and biodiversity change were identified and documented. We found that a pronounced decline of PC species and communities is driven by (a) damming of rivers, (b) habitat modifications that disturbed previous natural salinity gradients and settings in the studied area, (c) pollution and eutrophication, (d) invasive alien species, and (e) climate change. Four out of the 10 studied regions, namely, the Danube Delta–Razim Lake system, Dniester Liman, Dnieper–Bug estuary, and Taganrog Bay–Don Delta, contain favorable ecological conditions for PC communities and still host threatened endemic PC mollusk species. Distribution data are incomplete, but the scale of deterioration of PC species and communities is evident from the assembled data, as are major direct threats. Pontocaspian biodiversity in the BSB is profoundly affected by human activities. Standardized observation and collection data as well as precise definition of PC biota and habitats are necessary for targeted conservation actions. This study will help to set the research and policy agenda required to improve data collection to accommodate effective conservation of the unique PC biota. [ABSTRACT FROM AUTHOR]

The prominent new place of ecosystem services in environmental policy, land management and land planning requires that the best ecological knowledge be applied to ecosystem service quantification. Given strong evidence that functional diversity underpins the delivery of key ecosystem services, assessments of these services may progress rapidly using a trait-based approach., The trait-based approach shows promising results, especially for plant trait effects on primary production and some processes associated with carbon and nitrogen cycling in grasslands. However, there is a need to extend the proof of concept for a wider range of ecosystems and ecosystem services and to incorporate not only the functional characteristics of plants but those of other organisms with which plants interact for the provision of ecosystem services., The five papers in this Special Feature illustrate how some of the key conceptual and methodological challenges can be resolved, and provide a range of case studies across three continents. Relevant plant functional traits depict different axes of variation including stature, the leaf economics spectrum, and associated or independent variations in root or stem traits. The application of the trait approach to ecosystem processes underpinned by interactions between plants and other biota is illustrated for soil micro-organisms and granivorous invertebrates. There is strong evidence for the biomass ratio hypothesis (i.e. prevalent effects of the traits of dominant species through the community-weighted mean), along with less prevalent and more complex effects of heterogeneous trait values between species (i.e. functional divergence)., Synthesis. Together, the five papers in this Special Feature illustrate how trait-based approaches may help elucidate the complexity of ecological mechanisms operating in the field to determine ecosystem service delivery. To address scientific and management questions about the provision of multiple services, progress is needed in understanding how functional trade-offs and synergies within organisms scale up to interactions between ecosystem services. Service-oriented ecosystem management within the context of global change, or ecological restoration, remains a major challenge, but trait-based understanding opens new avenues towards more generic, integrated approaches. [ABSTRACT FROM AUTHOR]

Over the past several decades, a rapidly expanding field of research known as biodiversity and ecosystem functioning has begun to quantify how the world's biological diversity can, as an independent variable, control ecological processes that are both essential for, and fundamental to, the functioning of ecosystems. Research in this area has often been justified on grounds that (1) loss of biological diversity ranks among the most pronounced changes to the global environment and that (2) reductions in diversity, and corresponding changes in species composition, could alter important services that ecosystems provide to humanity (e.g., food production, pest/disease control, water purification). Here we review over two decades of experiments that have examined how species richness of primary producers influences the suite of ecological processes that are controlled by plants and algae in terrestrial, marine, and freshwater ecosystems. Using formal meta-analyses, we assess the balance of evidence for eight fundamental questions and corresponding hypotheses about the functional role of producer diversity in ecosystems. These include questions about how primary producer diversity influences the efficiency of resource use and biomass production in ecosystems, how primary producer diversity influences the transfer and recycling of biomass to other trophic groups in a food web, and the number of species and spatial/temporal scales at which diversity effects are most apparent. After summarizing the balance of evidence and stating our own confidence in the conclusions, we outline several new questions that must now be addressed if this field is going to evolve into a predictive science that can help conserve and manage ecological processes in ecosystems. [ABSTRACT FROM AUTHOR]

Butterflies are one of the best‐known insect groups, and they have been the subject of numerous studies in ecology and evolution, especially in the tropics. Much attention has been given to the fruit‐feeding butterfly guild in biodiversity conservation studies, due to the relative ease with which taxa may be identified and specimens sampled using bait traps. However, there remain many uncertainties about the macroecological and biogeographical patterns of butterflies in tropical ecosystems. In the present study, we gathered information about fruit‐feeding butterfly species in local communities from the Atlantic Forests of South America. The ATLANTIC BUTTERFLIES data set, which is part of ATLANTIC SERIES data papers, results from a compilation of 145 unpublished inventories and 64 other references, including articles, theses, and book chapters published from 1949 to 2018. In total, the data set contains 7,062 records (presence) of 279 species of fruit‐feeding butterflies identified with taxonomic certainty, from 122 study locations. The Satyrini is the tribe with highest number of species (45%) and records (30%), followed by Brassolini, with 13% of species and 12.5% of records. The 10 most common species correspond to 14.2% of all records. This data set represents a major effort to compile inventories of fruit‐feeding butterfly communities, filling a knowledge gap about the diversity and distribution of these butterflies in the Atlantic Forest. We hope that the present data set can provide guidelines for future studies and planning of new inventories of fruit‐feeding butterflies in this biome. The information presented here also has potential use in studies across a great variety of spatial scales, from local and landscape levels to macroecological research and biogeographical research. We expect that such studies be very important for the better implementation of conservation initiatives, and for understanding the multiple ecological processes that involve fruit‐feeding butterflies as biological indicators. No copyright restrictions apply to the use of this data set. Please cite this Data paper when using the current data in publications or teaching events. [ABSTRACT FROM AUTHOR]

It is now commonplace in community ecology to assess patterns of phylogenetic or functional diversity in order to inform our understanding of the assembly mechanisms that structure communities. While both phylogenetic and functional approaches have been used in conceptually similar ways, it is not clear if they both in fact reveal similar community diversity patterns or support similar inferences. We review studies that use both measures to determine the degree to which they support congruent patterns and inferences about communities.We performed a literature review with 188 analyses from 79 published papers that compared some facet of phylogenetic (PD) and functional diversity (FD) in community ecology. These studies generally report four main cases in which phylogenetic and functional information are used together in community analyses, to determine if: (a) there were phylogenetic signals in the measured traits in communities; (b) PD and FD were correlated with one another; (c) standardized PD and FD measures similarly revealed patterns of community over‐ or under‐dispersion; and (d) PD and FD were both related to other explanatory variables (e.g. elevation) similarly.We found that the vast majority of studies found both strong phylogenetic signals in their traits and positive correlations of PD and FD measures across sites. However, and surprisingly, we found substantial incongruencies for the other tests. Phylogenetic and functional dispersion patterns were congruent only about half the time. Specifically, when communities were phylogenetically over‐dispersed, these same communities were more likely to be functionally under‐dispersed. Similarly, we found that phylogenetic and functional relationships with independent predictors were incongruent in about half of the analyses.Synthesis. Phylogenetic signal tests and PD–FD correlations appear to strongly support the congruence between traits and phylogeny. It is surprising that strong phylogenetic signals appeared so ubiquitous given that ecological studies often analyse phylogenetically incomplete sets of species that have undergone ecological sorting. Despite the largely congruent findings based on phylogenetic signal tests and PD‐FD correlations, we found substantial incongruencies when researchers assessed either dispersion patterns or relationships with independent predictors. We discuss a number of potential ecological, evolutionary and methodological reasons for these incongruencies. Phylogenetic and functional information might reflect species ecological differences unequally with phylogenies better reflecting multivariate conserved elements of ecological similarity, and single traits better able to capture recent divergence, and both elements influence ecological patterns. [ABSTRACT FROM AUTHOR]

Ecologists have generally concluded that species distributions are not random (e.g. aggregate), based on single‐species studies that applied single‐species–based statistical methods, like the negative binomial model. Although it is common knowledge that some specific species in an ecological community present aggregate distributions, this does not necessarily imply that the entire community presents an aggregate distribution. Studying community‐level distributional aggregation patterns requires different statistical methods.Herein, by utilizing a novel conspecific‐encounter index derived from a multiple species Markov transition model that accounts for the non‐independent sampling of consecutive individuals along line transects, we were able to show that tree assemblages in tropical forest ecosystems can present a strong signal of extensive distributional interspersion.This interesting result is not unexpected, given the fact that neighbouring tree individuals in highly diverse tropical forests are usually of different species, resulting in strong niche packing or interspersed patterns. In contrast, for the amphibian assemblages surveyed from southwestern China and central‐south Vietnam, the conspecific‐encounter index was found to be consistently high, implying that amphibian communities tend to be highly aggregate in space.Conclusively, using the conspecific‐encounter index derived from the Markov non‐independent sampling model, we provide a legible definition of community‐level distributional aggregation as an interspersed or cluster‐like distribution of different species. This definition is not idiosyncratic, as it is coincident with the definition of the contagion index used in landscape ecology. To this end, the model used in this paper establishes a framework explicitly linking community ecology and landscape ecology from a multi‐object perspective. [ABSTRACT FROM AUTHOR]

The modeling of ecological data that include both abiotic and biotic factors is fundamental to our understanding of ecosystems. Repositories of biodiversity data, such as GBIF, iDigBio, Atlas of Living Australia, and SNIB (Mexico's National System of Biodiversity Information), contain a great deal of information that can lead to knowledge discovery about ecosystems. However, there is a lack of tools with which to efficiently extract such knowledge. In this paper, we present SPECIES, an open, web‐based platform designed to extract implicit information contained in large scale sets of ecological data. SPECIES is based on a tested methodology, wherein the correlations of variables of arbitrary type and spatial resolution, both biotic and abiotic, discrete and continuous, may be explored from both niche and network perspectives. In distinction to other modeling systems, SPECIES is a full stack exploratory tool that integrates the three basic components: data (which is incrementally growing), a statistical modeling and analysis engine, and an interactive visualization front end. Combined, these components provide a powerful tool that may guide ecologists toward new insights. SPECIES is optimized to support fast hypothesis prototyping and testing, analyzing thousands of biotic and abiotic variables, and presenting descriptive results to the user at different levels of detail. SPECIES is an open‐access platform available online (http://species.conabio.gob.mx), that is, powerful, flexible, and easy to use. It allows for the exploration and incorporation of ecological data and its subsequent integration into predictive models for both potential ecological niche and geographic distribution. It also provides an ecosystemic, network‐based analysis that may guide the researcher in identifying relations between different biota, such as the relation between disease vectors and potential disease hosts. SPECIES, an open web‐based platform designed for the exploratory analysis of large‐scale ecological datasets. SPECIES provides two perspectives: one based on ecological niche and geographic distribution modeling, and the other on ecological networks. SPECIES is optimized to support fast hypotheses prototyping and testing, analyzing thousands of biotic and abiotic variables and presenting descriptive results to the user at different levels of detail. [ABSTRACT FROM AUTHOR]

In recent years, ecologists have embraced the human dimensions of their discipline and expanded their remit to explore issues traditionally addressed by the social sciences and environmental humanities. This expansion offers opportunities to engage with diverse methodologies, some of which challenge the orthodoxies of conservation research; however, ecologists do not have the expertise to use social science methodologies in their work. In this Toolkit, we outline ways to improve social‐ecological research and outcomes through partnerships with qualitative researchers. Ecologists – who lack the epistemological and methodological preparation needed for productive qualitative or mixed methods study design – have often used quantitative methods to investigate social‐ecological systems. Though this has enhanced our ecological knowledge and led to the development of evidence‐based conservation practices, the biodiversity crisis continues to worsen as a result of human behaviours. Qualitative inquiry offers powerful insights into the drivers of social and behavioural phenomena but remains under‐represented in ecological research despite its broadening demographic. This presents a substantial missed opportunity that warrants rectifying. Here, we outline the qualitative research paradigm and highlight its benefits to ecology and ecologists. We also discuss a range of pitfalls and caveats ecologists encounter by not using appropriate qualitative research designs to support the exploration of their questions. We conclude by providing guidance for ecologists who intend to conduct research embracing qualitative or mixed paradigm designs. In order to address the human dimensions of ecology and conservation, it is essential to engage qualitative experts within and beyond the ecological science community. When fruitful collaborations form, research teams are able to approach some of ecology's most challenging problems from new perspectives, incorporating the views and knowledge of stakeholders on whom we rely for success. [ABSTRACT FROM AUTHOR]

Abstract: Recent evidence suggests that intransitive competition (as in the game “rock‐paper‐scissors,” and in contrast to transitive or hierarchical competition) may be common in natural plant communities. This is important as theoretical analyses indicate that intransitivity promotes species coexistence. However, while intransitivity is common, competitive relationships among many species in communities may vary from transitive to highly intransitive. With increasing numbers of species, variation in competitive interrelationships among species can take on vastly more variable topologies. Consequently, several indices can be used to capture topological variation that is relevant to the prediction of species coexistence. Different indices capture different elements of topological variation. In addition, evidence indicates that these indices vary in their capacity to predict coexistence, and that variation not captured by these indices also contributes to variation in species coexistence. We used aspatial and spatial competition models to explore how well different indices (Slater's i, Kendall and Babington Smith's d, Monsuur and Storcken's ν, Bezembinder's ρ and Bezembinder's δ′, plus two binary indices we call “unbeatability” [u] and “always‐beatability” [a]) predict coexistence under the full spectrum of competitive tournament topologies for three to eight species, and a large sample of existing tournament topologies for nine species. All indices explored were generally better at predicting short‐term coexistence (i.e. the number of generations until the first extinction) compared to long‐term coexistence (i.e. generations until monoculture or long‐term species richness in aspatial and spatial models respectively). Indices also differed in performance: Kendall and Babington Smith's d (a measure of the number intransitive cycles among an assemblage's three‐species subsets that has also been reformulated as the relative intransitivity index) was the best predictor of short‐term coexistence; in terms of long‐term coexistence, the best predictor was typically d or u, the latter indicating the presence or absence of a species capable of outcompeting all its competitors. Synthesis. The indices employed here capture different elements of topological variation. Existing indices that capture aspects of intransitive competition vary in their capacity to predict coexistence in competition models. The more continuous nature of Kendall and Babington Smith's d index likely contributed to its robust performance; likewise, the ability of unbeatability to detect intransitivities involving the strongest competitors helps explain its success. [ABSTRACT FROM AUTHOR]

Abstract: To address the lack of information about the shape and extent of real dispersal kernels, Bullock et al. (Journal of Ecology 105:6‐19, 2017) synthesised empirical information on seed dispersal distances. Testing the fit of a variety of probability density functions, they found no function was the best‐fitting for all datasets but some outperformed others. Cousens et al. (Journal of Ecology, 2017) focus on the specific finding of the generally poor fit of the WALD function to wind dispersal data and use this to argue that mechanistically derived functions would not be expected to fit data particularly well. We agree in part with this argument and discuss the issues that may lead to poor fit, including the simplifying assumptions of the WALD and the complexity of the dispersal process. We explain the fundamental linkage between the mechanistic form of the WALD and the derived function used for fitting to data. We demonstrate, however, that the logic that a mechanistically based function could fit to data is valid, under the hypothesis that it encompasses the key processes determining the dispersal kernel. This argument is supported by the facts that: (1) our analyses and others have shown the WALD performs well in a number of cases; and (2) the WALD is the best‐fitting function for an example in which we simulate dispersal data using a realistic representation of variability in the wind dispersal process. Synthesis. While there are reasons that mechanistically derived functions may not fit well to empirical data, they do in some empirical and simulated cases and this suggests they can capture the dispersal behaviour of real systems. Mechanistic functions should be explored along with other more general functions when describing empirical data to investigate their simplifying assumptions and to add to our arsenal of functions for analysing dispersal data. Analyses using these functions are critical if we are to move from simply describing the system in which the data were gathered to gaining more general insights into dispersal and predicting its consequences. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to illustrate the changing diversity patterns of native freshwater fish in the past two centuries and to identify priority locations for native fish conservation to counter future degradation. Location: Japanese archipelago. Methods: We used the published native fish fauna data in 39 lakes across Japan, analysing historical and current diversity and projecting future distribution patterns based on the Japanese Red List. We assessed fish assemblages' taxonomic, phylogenetic, and functional alpha and beta diversity across different periods. Additionally, we proposed a cumulative diversity index that incorporated taxonomic, phylogenetic and functional facets, and then examined its relationship with the latitudinal positioning of the lakes across periods. Results: We observed a significant decrease in the richness of native freshwater fish since historical periods. Accompanying this decline were significant reductions in both phylogenetic relatedness and functional redundancy. Fish beta diversity increased from the past to the present and is predicted to decline drastically, indicating an ongoing homogenization process. Using the cumulative diversity index, we identified Hokkaido and Kyushu as crucial habitats for endemic fishes. These islands, with unique biogeographical backgrounds, contributed substantially to the national dissimilarity patterns of native fish assemblages in the historical period. However, the contribution is diminishing due to the ongoing decline in fish endemism. Main Conclusions: The conservation priority of native freshwater fish in Japan should be assigned to Hokkaido and Kyushu due to the inhabited endemic species. The proposed framework for assessing the cumulative diversity of biotic communities presented the potential to aid macroecological explorations that underpin biodiversity conservation. [ABSTRACT FROM AUTHOR]

Conservation efforts have focused largely on species, yet ecosystem management is suggested to be a more efficient strategy for biodiversity management. With increasing numbers of threatened species, ecosystems and ecological communities, and limited resources, an approach that delivers the best conservation outcomes across multiple levels of biodiversity is crucial. In this study, we compared a species approach and a community approach to management by evaluating the number of threatened species benefiting from actions targeted at threatened ecological communities (TECs), and vice versa. We ran three analyses: one theoretical, and two spatially‐explicit analyses accounting for co‐occurrence in distributions and site‐based actions. We found that of 124 actions, 61 were common to species and TECs. Yet, the overlap of actions was lower when considering species and TEC co‐occurrences across the distributions, and was mostly lost at the site‐scale. In all analyses, focusing on species management resulted in a greater percentage of actions considered, thus potentially benefiting more species and TECs. We suggest that when there is limited capacity to perform formal prioritization analyses, our process could identify actions addressing widespread and common threats impacting both species and communities. Further, simultaneously managing both species and TECs would potentially deliver a more effective solution. [ABSTRACT FROM AUTHOR]

To offer an increased understanding of the spatial patterns, temporal, social and physical predictors of the conversion and transformations of land use in Lake Victoria basin, an assessment of proximate and underlying forces is presented. This study discusses key theoretical underpinnings for the manifold linkages existing between selected drivers of land-use changes around the basin and their consequences on human well-being. Using a meta-analytical research design, the paper analyses ecosystems level cases of the causes of land use and cover changes in the basin, to determine any spatio-temporal or institutional patterns and dynamics. A suite of recurrent core variables has been identified to influence land use and cover changes in the basin. The most prominent of these at the underlying category are climatic factors, economic factors, institutions, national and regional policies, population growth and other remote influences. At the proximate level, these factors drive cropland expansion, overgrazing, infrastructure extension and rates of land degradation. These are supported by empirical evidence from the basin. This assessment is crucial for appropriate local and transboundary policy interventions, which have to be fine-tuned to the locale-specific dynamic patterns associated with the inherent ecosystems changes. [ABSTRACT FROM AUTHOR]

Aim Biotic homogenization describes the process by which species invasions and extinctions increase the genetic, taxonomic or functional similarity of two or more biotas over a specified time interval. The study of biotic homogenization is a young and rapidly emerging research area in the budding field of conservation biogeography, and this paper aims to synthesize our current knowledge of this process and advocate a more systematic approach to its investigation. Methods Based on a comprehensive examination of the primary literature this paper reviews the process of biotic homogenization, including its definition, quantification, underlying ecological mechanisms, environmental drivers, the empirical evidence for different taxonomic groups, and the potential ecological and evolutionary implications. Important gaps in our knowledge are then identified, and areas of new research that show the greatest promise for advancing our current thinking on biotic homogenization are highlighted. Results Current knowledge of the patterns, mechanisms and implications of biotic homogenization is highly variable across taxonomic groups, but in general is incomplete. Quantitative estimates are almost exclusively limited to freshwater fishes and plants in the United States, and the principal mechanisms and drivers of homogenization remain elusive. To date research has focused on taxonomic homogenization, and genetic and functional homogenization has received inadequate attention. Trends over the past decade, however, suggest that biotic homogenization is emerging as a topic of greater research interest. Main conclusions My investigation revealed a number of important knowledge gaps and priority research needs in the science of biotic homogenization. Future studies should examine the homogenization process for different community properties (species occurrence and abundance) at multiple spatial and temporal scales, with careful attention paid to the various biological mechanisms (invasions vs. extinctions) and environmental drivers (environmental alteration vs. biotic interactions) involved. Perhaps most importantly, this research should recognize that there are multiple possible outcomes resulting from the accumulation of species invasions and extinctions, including biotic differentiation whereby genetic, taxonomic or functional similarity of biotas decreases over time. [ABSTRACT FROM AUTHOR]

Although the concepts of scale and biological diversity independently have received rapidly increasing attention in the scientific literature since the 1980s, the rate at which the two concepts have been investigated jointly has grown much more slowly. We find that scale considerations have been incorporated explicitly into six broad areas of investigation related to biological diversity: (1) heterogeneity within and among ecosystems, (2) disturbance ecology, (3) conservation and restoration, (4) invasion biology, (5) importance of temporal scale for understanding processes, and (6) species responses to environmental heterogeneity. In addition to placing the papers of this Special Feature within the context of brief summaries of the expanding literature on these six topics, we provide an overview of tools useful for integrating scale considerations into studies of biological diversity. Such tools include hierarchical and structural-equation modelling, kriging, variable-width buffers, k-fold cross-validation, and cascading graph diagrams, among others. Finally, we address some of the major challenges and research frontiers that remain, and conclude with a look to the future. [ABSTRACT FROM AUTHOR]

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Areas of high biodiversity often coincide with communities living in extreme poverty. As a livelihood support, these communities often harvest wild products from the environment. But harvest activities can have negative impacts on fragile and globally important ecosystems. This paper examines trade-offs in ecological protection and community welfare from the harvest of wild products. With a novel model and empirical evidence, I show that management of harvest activity does not always resolve these trade-offs. In a model of continuous harvests in a two-dimensional landscape, managed harvest activity improves welfare, but is uniformly bad for other ecosystem services that are sensitive to the presence (as opposed to the intensity) of human activity. Empirical results from a unique dataset of mushroom harvesters in Yunnan, China suggest more experienced, poorer, and more vulnerable individuals tend to rely on more distant harvests. Thus, policies that limit the extent of forest travel, such as protected areas, may protect fragile ecosystems but can have a disproportionately negative effect on those most vulnerable. [ABSTRACT FROM AUTHOR]

Both abiotic and biotic gradients exist in soils, and several of these gradients have been shown to select for plant traits. Moreover, plants possess a multitude of traits that can lead to strong niche construction (i.e. plant-induced changes to soils). Our objectives in this paper are to outline both empirical and theoretical evidence for the evolutionary consequences of plant-soil linkages and feedbacks on plants along soil heterogeneity gradients., We describe a simple mathematical model of plant evolution to explore the relationship between the sign and magnitude of feedback and the divergence of plant traits. We also constructed an individual-based simulation model to study the conditions under which plant-soil feedbacks occur, niche construction evolves, and plant traits diverge., This approach allows us to address specific hypotheses regarding relationships between positive and negative plant-soil feedback with variation in niche construction, the strength of selective gradients and the relative importance of local adaptation vs. feedbacks., The models suggest that feedbacks between soils and plants may commonly result in evolutionary interactions. The simulation model indicates that plant traits can diverge with niche construction and traits can be selected for in response to niche construction. However, the magnitude of feedbacks and how strongly they evolve depends on the amount of gene flow and the strength of selective gradients over time., These results suggest that plant-soil feedback can lead to evolution in plants and reveals new research directions for further inquiry. Questions addressing trade-offs and relationships between positive and negative feedbacks as well as adaptation and maladaptation of plant traits represent important frontiers in plant-soil feedback studies. [ABSTRACT FROM AUTHOR]

The political will to reduce global GHG emissions has largely contributed to increased global biofuel production and trade. The expanding cultivation of energy crops may drive changes in the terrestrial ecosystems such as land cover and biodiversity loss. When biomass replaces fossil energy carriers, sustainability criteria are therefore crucial to avoid adverse impacts and ensure a net positive GHG balance. The European Union has set mandatory sustainability criteria for liquid biofuels in its Renewable Energy Directive ( RED) 2009/28/ EC to ensure net positive impacts of its biofuel policy. The adoption of sustainability criteria in other world regions and their extension to solid and gaseous biomass in the EU is ongoing. This paper examines the effect of the EU RED sustainability criteria on the availability of biomass resources at global and regional scale. It quantifies the relevance of sustainability criteria in biomass resource assessments taking into account the criteria's spatial distribution. This assessment does not include agricultural and forestry residues and aquatic biomass. Previously unknown interrelations between sustainability criteria are examined and described for ten world regions. The analysis concludes that roughly 10% (98.5 EJ) of the total theoretical potential of 977.2 EJ occurs in areas free of sustainability concerns. [ABSTRACT FROM AUTHOR]

The biodiversity-ecosystem functioning (BEF) relationship is central in community ecology. Its drivers in competitive systems (sampling effect and functional complementarity) are intuitive and elegant, but we lack an integrative understanding of these drivers in complex ecosystems. Because networks encompass two key components of the BEF relationship (species richness and biomass flow), they provide a key to identify these drivers, assuming that we have a meaningful measure of functional complementarity. In a network, diversity can be defined by species richness, the number of trophic levels, but perhaps more importantly, the diversity of interactions. In this paper, we define the concept of trophic complementarity (TC), which emerges through exploitative and apparent competition processes, and study its contribution to ecosystem functioning. Using a model of trophic community dynamics, we show that TC predicts various measures of ecosystem functioning, and generate a range of testable predictions. We find that, in addition to the number of species, the structure of their interactions needs to be accounted for to predict ecosystem productivity. [ABSTRACT FROM AUTHOR]

Understanding the influence of the environment on the functional structure of ecological communities is essential to predict the response of biodiversity to global change drivers. Ecological theory suggests that multiple environmental factors shape local species assemblages by progressively filtering species from the regional species pool to local communities. These successive filters should influence the various components of community functional structure in different ways. In this paper, we tested the relative influence of multiple environmental filters on various metrics of plant functional trait structure (i.e. 'community weighted mean trait' and components of functional trait diversity, i.e. functional richness, evenness and divergence) in 82 vegetation plots in the Guisane Valley, French Alps. For the 211 sampled species we measured traits known to capture key aspects of ecological strategies amongst vascular plant species, i.e. leaf traits, plant height and seed mass (LHS). A comprehensive information theory framework, together with null model based resampling techniques, was used to test the various environmental effects. Particular community components of functional structure responded differently to various environmental gradients, especially concerning the spatial scale at which the environmental factors seem to operate. Environmental factors acting at a large spatial scale (e.g. temperature) were found to predominantly shape community weighted mean trait values, while fine-scale factors (topography and soil characteristics) mostly influenced functional diversity and the distribution of trait values among the dominant species. Our results emphasize the hierarchical nature of ecological forces shaping local species assemblage: large-scale environmental filters having a primary effect, i.e. selecting the pool of species adapted to a site, and then filters at finer scales determining species abundances and local species coexistence. This suggests that different components of functional community structure will respond differently to environmental change, so that predicting plant community responses will require a hierarchical multi-facet approach. [ABSTRACT FROM AUTHOR]

The Neotropical region (tropical America) is the most species rich region on Earth. Several causes have been proposed to explain this extraordinary biodiversity, which may be very roughly classified into two major categories: 'biotic' (e.g. soil adaptations; biotic interactions with pollinators, dispersers and herbivores; niche conservatism; dispersal ability) and 'abiotic' (e.g. time; rainfall, temperature and area; mountain uplift; hydrological changes). In this paper we review the evidence for each of these postulated causes of diversification and provide general directions towards further testing. We highlight the need of more well-sampled and dated phylogenies and urge increased inter-disciplinary collaboration. [ABSTRACT FROM AUTHOR]

Although the contribution of community members to functional diversity is a key question of conservation ecology, its measurement and interpretation are rather problematic. In this paper, we suggest a novel method for decomposing functional diversity. To do this we consider functional units (i.e. species or a group of species with identical traits) as the functional building blocks of communities. Then we propose the use of a recently developed measure of functional diversity (called modified functional attribute diversity or MFAD) and suggest additive decomposition of MFAD into functional values contributed by the functional units. We point out that functional values are related to changes in MFAD if the functional unit is removed from the community. This property of decomposition allows the quantification of the contribution of community members to functional diversity. By studying artificial and actual communities we compare the performance of our new method with other recently developed contribution measures, which are based on dendrograms and ordinations. Both theoretical considerations and analyses of artificial and actual data sets suggest that the proposed method of calculating functional values expresses more explicitly the contribution of community members to functional diversity and hereby can be used as a simple, yet efficient method for searching for functional keystones in ecological communities or for quantifying the contribution of community members to functional diversity. [ABSTRACT FROM AUTHOR]

Successful conservation plans are not solely achieved by acquiring optimally designed reserves. Ongoing monitoring and management of the biodiversity in those reserves is an equally important, but often neglected or poorly executed, part of the conservation process. In this paper we address one of the first and most important steps in designing a monitoring program – deciding what to monitor. We present a strategy for prioritizing species for monitoring and management in multispecies conservation plans. We use existing assessments of threatened status, and the degree and spatial and temporal extent of known threats to link the prioritization of species to the overarching goals and objectives of the conservation plan. We consider both broad and localized spatial scales to capture the regional conservation context and the practicalities of local management and monitoring constraints. Spatial scales that are commensurate with available data are selected. We demonstrate the utility of this strategy through application to a set of 85 plants and animals in an established multispecies conservation plan in San Diego County, California, USA. We use the prioritization to identify the most prominent risk factors and the habitats associated with the most threats to species. The protocol highlighted priorities that had not previously been identified and were not necessarily intuitive without systematic application of the criteria; many high-priority species have received no monitoring attention to date, and lower-priority species have. We recommend that in the absence of clear focal species, monitoring threats in highly impacted habitats may be a way to circumvent the need to monitor all the targeted species. [ABSTRACT FROM AUTHOR]

The purpose of this comment paper is to highlight the need for more research that aims to develop strategies and methods for establishing and maintaining native grasses in degraded pastures. Clues to finding the best strategies are linked to the vigorous debate concerning the relationship between biodiversity and ecosystem function, which has resonated in ecological research for more than 20 years. Studies aimed at investigating the operational validity of the ‘sampling effect’ hypothesis vs. the ‘niche complementarity’ hypothesis could provide valuable direction on how to successfully re-establish healthy and stable native pasture communities, including the number of species and functional groups needed. Once strategies have been developed, then practical methods on grazing management and sowing are also needed. In the long run, research initiatives in this direction could act to benefit the conservation of native grass diversity, while at the same time, sustain important ecological (and economic) functions such as production, nutrient cycling and resistance to invasion. [ABSTRACT FROM AUTHOR]

In arid and semiarid Australia fossorial vertebrates have been a major component of the soil biota mediating many fundamental landscape processes. However, many species such as the burrowing bettong ( Bettongia lesueur) have become seriously depleted following European pastoral settlement. As ‘landscape engineers’, they were responsible for creating and maintaining a high degree of surface heterogeneity that promoted a diverse and productive herbaceous understorey, particularly in ‘hard-red’ communities dominated by mulga ( Acacia aneura). While their regional extinction has had major impacts by contributing to desertification and loss of biodiversity, relict warrens ‘engineered’ by B. lesueur still remain in certain ecosystems and despite continual weathering, contribute significantly to herbage productivity and species diversity. This paper details the results obtained from a number of field studies aimed at determining the distribution of relict warrens at contrasting scales and their influence on landscape patch dynamics resulting from their impacts on soil nutrients, herbage composition and herbivory. Finally, the conservation implications following the continental extinction of this species and the resulting loss of fundamental ecosystem services, as well as cultural values, are discussed in the context of future re-introduction efforts. [ABSTRACT FROM AUTHOR]

1 An important goal of community ecology is the assessment of factors that are likely to influence the spatio-temporal distribution of species assemblages and diversity. Surprisingly, most statistical methods devoted to this have remained poorly interconnected, as well as poorly connected with the popular metrics of diversity estimation. In the present paper we show that important questions related to determinants of species diversity can be specified through a simple multivariate linear model and explored, in common diversity metrics, using standard methods and routines of variance/covariance decomposition. 2 Thanks to an unusual form of presentation of taxonomic data into a table of species occurrences, which considers the individuals as data units, Shannon and Simpson indices as well as species richness can all be expressed as a (weighted) sum of squares. Subsequent apportionments into explained and residual sum of squares provide direct estimates of the beta- and alpha-diversity components with respect to either categorical habitat types or continuous gradient variables. Appropriate statistics and non-parametric tests are available to assess the significance of these components. 3 Explicit analytical relationships exist between the linear approximation of the table of species occurrences by sampling sites, and the more classical table of species abundances by sites. Therefore, direct links with methods of ordination in reduced space, such as correspondence analysis and canonical correspondence analysis, provide opportunities for partitions that preserve consistency with usual diversity indices. The sum of squares of the approximated occurrence table provides measures of intersites beta-diversity, from which measures of dissimilarity with explicit references to diversity indices can be derived. Such measures are amenable to distance-based apportionments through multivariate variograms and multiscale ordination. 4 What are the relative effects of the biological, environmental and anthropogenic factors and of their potential interactions on species diversity? Are these effects stable across scales, from landscape to region, between regions and across ecosystems? The methodological integration proposed in our analytical framework enables one to address these questions using standard statistical tools, and opens new prospects for quantitative biodiversity studies. This also paves the way towards refined models for predicting species diversity at unsampled locations. [ABSTRACT FROM AUTHOR]

The assumption that the description of any system depends on spatial and temporal scale has moved researchers to incorporate scale as another factor in determining the mechanisms explaining species diversity and distribution. Although most researchers agree that processes that occur at different spatial and temporal scales affect ecological communities, empirical support is still scarce. In this paper, we seek to discern whether the relationship between abundance, biomass, and species diversity, on the one hand, and habitat heterogeneity, on the other, holds across temporal and spatial scales. Moreover, we analyse whether the pattern/variation found depends on the taxonomic level, and the diversity index used. To answer these questions, we sampled arthropod assemblages across three nested temporal and spatial scales. In general, we found variability in the responses to habitat heterogeneity across scales according to the assemblage descriptor, the taxonomic level selected, and the diversity index used. Our results suggest that generalization is difficult and extrapolation should be made with caution. Moreover, the use of more than one diversity index would provide additional and complementary information about species-distribution patterns and the mechanisms generating these patterns. [ABSTRACT FROM AUTHOR]

Rivers are conduits for materials and energy; this, the frequent and intense disturbances that these systems experience, and their narrow, linear nature, create problems for conservation of biodiversity and ecosystem functioning in the face of increasing human influence. In most parts of the world, riparian zones are highly modified. Changes caused by alien plants — or environmental changes that facilitate shifts in dominance creating novel ecosystems — are often important agents of perturbation in these systems. Many restoration projects are underway. Objective frameworks based on an understanding of biogeographical processes at different spatial scales (reach, segment, catchment), the specific relationships between invasive plants and resilience and ecosystem functioning, and realistic endpoints are needed to guide sustainable restoration initiatives. This paper examines the biogeography and the determinants of composition and structure of riparian vegetation in temperate and subtropical regions and conceptualizes the components of resilience in these systems. We consider changes to structure and functioning caused by, or associated with, alien plant invasions, in particular those that lead to breached abiotic- or biotic thresholds. These pose challenges when formulating restoration programmes. Pervasive and escalating human-mediated changes to multiple factors and at a range of scales in riparian environments demand innovative and pragmatic approaches to restoration. The application of a new framework accommodating such complexity is demonstrated with reference to a hypothetical riparian ecosystem under three scenarios: (1) system unaffected by invasive plants; (2) system initially uninvaded, but with flood-generated incursion of alien plants and escalating invasion-driven alteration; and (3) system affected by both invasions and engineering interventions. The scheme has been used to derive a decision-making framework for restoring riparian zones in South Africa and could guide similar initiatives in other parts of the world. [ABSTRACT FROM AUTHOR]

In this paper, I examine the dynamics of species richness in a model system in which multiple species compete in a metacommunity (multiple patches linked by dispersal). Patches lie along an environmental gradient, and new species are introduced into the system by speciation of existing species. This model is used to explore how the ecological similarity of species influences the patterns in community structure that result and to determine whether patterns in fossil and systematics data may be signatures for different types of community structure. Making species more similar overall along the entire gradient or making new species that have more similar optimal positions along the gradient to their progenitor both increase the time required to drive species extinction. As a result, making species more similar ecologically to one another increases overall species richness because of an increased frequency of transient species in the system. Having more transient species in systems shifted the longevity distributions of species in the fossil record towards having a greater frequency of shorter duration species, and the age distribution of extant species that would be estimated from molecular phylogenies also had a higher frequency of younger aged species. Comparisons of these results with species longevity distributions extracted from two data sets and with species ages derived from species-level molecular phylogenies strongly suggest that transient species are an important component of real biological communities. [ABSTRACT FROM AUTHOR]

We conducted an intensive review of conservation science to find out whether the field has tracked priorities over the past 20 years. A total of 628 papers from the literature, for the years 1984, 1994, and 2004, were surveyed. For each paper, we recorded where conservation research was done and what was studied. We found geographic gaps in conservation research, with marine, tundra, and desert biomes being studied less than other systems. We also found taxonomic gaps, with amphibians being understudied as compared to other, less threatened, taxonomic groups. Finally, we discovered that studies of invasive species are still lacking, despite the magnitude of the threat they pose to global biodiversity. Although there was a weak trend towards filling these gaps between 1984 and 2004, progress has been slow. To be more effective, the research community must quickly redirect research to better match conservation priorities. [ABSTRACT FROM AUTHOR]

Aim The aim of this paper is to evaluate the combined effects of geographical distance and environmental distance on patterns of species similarity (similarity in species composition between sites), and to identify factors affecting the rate of decay in species similarity with each type of distance. Location Israel. Methods Data on species composition of land snails and land birds were recorded in 27 sites of 1 × 1 km scattered across a rainfall gradient in Israel. Matrices of similarity in species composition between all pairs of sites were computed and analysed with respect to corresponding matrices of geographical distance and rainfall distance (defined as the difference in mean annual rainfall between sites, and used as a measure of environmental distance). Mantel tests were applied to determine the correlation between species similarity and each type of distance. Factors affecting the decay in species similarity were investigated by comparing different subsets of the data using randomization tests. Results Both rainfall distance and geographical distance had negative effects on species similarity. The effect of rainfall distance was statistically significant even after controlling for differences in geographical distance, and vice versa. The per-unit effect of rainfall distance on species similarity decreased with increasing geographical distance, indicating that the two types of distances interacted in determining the similarity in species composition. Snails showed a higher rate of decay in species similarity with geographical distance than birds, and large snails showed a higher rate of decay than small snails, which are better passive dispersers. The per-unit effects of both rainfall distance and geographical distance on species similarity were higher in the desert region than in the Mediterranean region. Analyses focusing on a grain size of 10 × 10 m showed a lower similarity in species composition and a lower rate of decay in species similarity with rainfall distance than analyses carried out at a grain size of 1 × 1 km. Main conclusions Patterns of similarity in species composition are influenced by the combined effects of environmental variation, the position of the area along environmental gradients, the dispersal properties of the component species, and the scale (both spatial extent and grain size) at which the patterns are examined. [ABSTRACT FROM AUTHOR]

Paleoecological evidence and paleoclimatic records indicate that there was a plant poleward migration in latitude and an upward shift in elevation with increased temperatures after the last glaciation. Recent studies have shown that global warming over the past 100 years has been having a noticeable effect on living systems. Current global warming is causing a poleward and upward shift in the range of many plants and animals. Climate change, in connection with other global changes, is threatening the survival of a wide range of plant and animal species. This raises the question: can existing reserves really preserve current levels of biological diversity in the long term given the present rapid pace of climate change? The present paper deals with this question in the context of the responses of plants and animals to global climate change, based on a literature review. Consequently, we recommend expanding reserves towards the poles and/or towards higher altitudes, to permit species to shift their ranges to keep pace with global warming. (Managing editor: Ya-Qin Han) [ABSTRACT FROM AUTHOR]

Two major international initiatives – the Convention on Biological Diversity's target to reduce the rate of biodiversity loss by 2010, and the Millennium Ecosystem Assessment – raise the profile of ecological data on the changing state of nature and its implications for human well-being. This paper is intended to provide a broad overview of current knowledge of these issues. Information on changes in the status of species, size of populations, and extent and condition of habitats is patchy, with little data available for many of the taxa, regions and habitats of greatest importance to the delivery of ecosystem services. However, what we do know strongly suggests that, while exceptions exist, the changes currently underway are for the most part negative, anthropogenic in origin, ominously large and accelerating. The impacts of these changes on human society are idiosyncratic and patchily understood, but for the most part also appear to be negative and substantial. Forecasting future changes is limited by our poor understanding of the cascading impacts of change within communities, of threshold effects, of interactions between the drivers of change, and of linkages between the state of nature and human well-being. In assessing future science needs, we not only see a strong role for ecological data and theory, but also believe that much closer collaboration with social and earth system scientists is essential if ecology is to have a strong bearing on policy makers. [ABSTRACT FROM AUTHOR]

The mid-domain effect (MDE) aims to explain spatial patterns in species richness invoking only stochasticity and geometrical constraints. In this paper, we used simulations to show that its main qualitative prediction, a hump-shaped pattern in species richness, converges to the expectation of a spatially bounded neutral model when communities are linked by short-distance migration. As these two models can be linked under specific situations, neutral theory may provide a mechanistic population level basis for MDE. This link also allows establishing in which situations MDE patterns are more likely to be found. Also, in this situation, MDE models could be used as a first approximation to understand the role of both stochastic (ecological drift and migration) and deterministic (adaptation to environmental conditions) processes driving the spatial structure of species richness. [ABSTRACT FROM AUTHOR]

Dispersal is universally considered important for biodiversity conservation. However, the significance of long- as opposed to short-distance dispersal is insufficiently recognized in the conservation context. Long-distance dispersal (LDD) events, although typically rare, are crucial to population spread and to maintenance of genetic connectivity. The main threats to global biodiversity involve excessive LDD of elements alien to ecosystems and insufficient dispersal of native species, for example, because of habitat fragmentation. In this paper, we attempt to bridge the gap in the treatment of LDD by reviewing the conservation issues for which LDD is most important. We then demonstrate how taking LDD into consideration can improve conservation management decisions. [ABSTRACT FROM AUTHOR]

This special issue ofDiversity and Distributionspresents six papers that contribute to the assembly of a general research agenda for studying long-distance dispersal (LDD) across a variety of taxonomic groups (e.g. birds, fish, aquatic invertebrates and plants), ecosystems (e.g. terrestrial and marine ecosystems, wetlands and grasslands) and thematic fields (e.g. biological transport, marine biology, biogeochemistry and biodiversity conservation). This editorial emphasizes the need to develop a network integrating different research approaches (‘yellow brick roads’) to address the great challenge (‘finding the end of the rainbow’) of quantifying, understanding and predicting LDD and its implications. I review the key avenues for future research suggested in the special issue contributions, and stress the critical importance of properly considering the spatial and temporal scales relevant to the process and system of interests. I propose combining absolute and proportional definitions of LDD as a default practice in any investigation of LDD processes. When LDD is defined primarily by an absolute critical distance that characterizes key feature(s) of the system of interest, a quantitative assessment of the proportion of dispersal events expected to move beyond this critical threshold distance should also be provided. When LDD is defined primarily by a certain small fraction of dispersal events that travel longer than all others, an estimate of the absolute distance associated with this high percentile at the tail of the dispersal curve should also be added. [ABSTRACT FROM AUTHOR]

This paper examines species richness, abundance, and body size in deep-sea gastropods and how they vary over depth, which is a strong correlate of nutrient input. Previous studies have documented the empirical relationships among these properties in terrestrial and coastal ecosystems, but a full understanding of how these patterns arise has yet to be obtained. Examining the relationships among macroecological variables is a logical progression in deep-sea ecology, where patterns of body size, diversity, and abundance have been quantified separately but not linked together. 196–5042 m depth in the western North Atlantic. Individuals analysed represent all Vetigastropoda and Caenogastropoda (Class Gastropoda) with intact shells, excluding Ptenoglossa, collected by the Woods Hole Benthic Sampling Program (3424 individuals representing 80 species). Biovolume was measured for every individual separately (i.e. allowing the same species to occupy multiple size classes) and divided into log2 body size bins. Analyses were conducted for all gastropods together and separated into orders and depth regions (representing different nutrient inputs). A kernel smoothing technique, Kolmogorov-Smirnov test of fit, and OLS and RMA were used to characterize the patterns. Overall, the relationship between the number of individuals and species is right skewed. There is also a positive linear relationship between the number of individuals and the number of species, which is independent of body size. Variation among these relationships is seen among the three depth regions. At depths inferred to correspond with intermediate nutrient input levels, species are accumulated faster given the number of individuals and shift from a right-skewed to a log-normal distribution. A strong link between body size, abundance, and species richness appears to be ubiquitous over a variety of taxa and environments, including the deep sea. However, the nature of these relationships is affected by the productivity regime and scale at which they are examined. [ABSTRACT FROM AUTHOR]

Studies of microbial communities from aquatic ecosystems provide important insights into relations between various aspects of ecosystem functioning and changes in biodiversity. Aquatic microbial systems provide a valuable counterpoint to studies of terrestrial systems, because patterns reflect consequences of interactions occurring over many generations of community development, and are unlikely to represent artifacts of the initial conditions established in experimental communities. In this paper we re-analyse our previously published data to separate the contributions of temporal and spatial variation to overall variation in ecosystem functioning. A new analysis based on re-sampling confirms a negative relationship between richness and the variability of one ecosystem process, carbon dioxide flux. The negative relationship reflects high variation among communities of low species richness, rather than high temporal variation within communities of low richness. We also review the various transformations and summary statistics proposed as alternate measures of variability in ecosystem functioning, to point out that different measures are often appropriate for different kinds of data. Finally, we conclude that arguments about the cosmopolitan distribution of microbes do not preclude the existence of important relations between microbial species richness and ecosystem functioning. [ABSTRACT FROM AUTHOR]

Literature on plant leaf litter decomposition is substantial, but only in recent years have potential interactions among leaves of different species during decomposition been examined. We review emerging research on patterns of mass loss, changes in nutrient concentration, and decomposer abundance and activity when leaves of different species are decaying in mixtures. Approximately 30 papers have been published that directly examine decomposition in leaf mixtures as well as in all component species decaying alone. From these litter-mix experiments, it is clear that decomposition patterns are not always predictable from single-species dynamics. (Characteristics of decomposition in litter-mixes that deviate from responses predicted from decomposition of single-species litters alone are designated "non-additive"; "additive" responses in mixes are predictable from component species decaying alone.) Non-additive patterns of mass loss were observed in 67% of tested mixtures; mass loss is often (though not always) increased when litters of different species are mixed. Observed mass loss in some mixtures is as much as 65% more extensive than expected from decomposition of single-species litter, but more often mass loss in mixtures exceeds expected decay by 20% or less. Nutrient transfer among leaves of different species is striking, with 76% of the mixtures showing non-additive dynamics of nutrient concentrations. Non-additive patterns in the abundance and activity of decomposers were observed in 55% and 65% of leaf mixes, respectively. We discuss some methodological details that likely contribute to conflicting results among mixed-litter studies to date. Enough information is available to begin formulating mechanistic hypotheses to explain patterns in litter-mix experiments. Emerging patterns in the mixed-litter decomposition literature have implications for relationships between biodiversity and ecosystem function (in this case, the function being decomposition), and for potential mechanisms through which invasive plant species could alter carbon and nutrient dynamics in ecosystems. [ABSTRACT FROM AUTHOR]

In a selected literature survey we reviewed studies on the habitat heterogeneity–animal species diversity relationship and evaluated whether there are uncertainties and biases in its empirical support. World-wide. We reviewed 85 publications for the period 1960–2003. We screened each publication for terms that were used to define habitat heterogeneity, the animal species group and ecosystem studied, the definition of the structural variable, the measurement of vegetation structure and the temporal and spatial scale of the study. The majority of studies found a positive correlation between habitat heterogeneity/diversity and animal species diversity. However, empirical support for this relationship is drastically biased towards studies of vertebrates and habitats under anthropogenic influence. In this paper, we show that ecological effects of habitat heterogeneity may vary considerably between species groups depending on whether structural attributes are perceived as heterogeneity or fragmentation. Possible effects may also vary relative to the structural variable measured. Based upon this, we introduce a classification framework that may be used for across-studies comparisons. Moreover, the effect of habitat heterogeneity for one species group may differ in relation to the spatial scale. In several studies, however, different species groups are closely linked to ‘keystone structures’ that determine animal species diversity by their presence. Detecting crucial keystone structures of the vegetation has profound implications for nature conservation and biodiversity management. [ABSTRACT FROM AUTHOR]

Journal of Applied Ecology (2003) 40, 939–946 [ABSTRACT FROM AUTHOR]

Many methods for estimating the functional diversity of biological communities rely on measuring geometrical properties of n‐dimensional hypervolumes in a trait space. To date, these properties are calculated from individual hypervolumes or their pairwise combinations. Our capacity to detect functional diversity patterns due to the overlap of multiple hypervolumes is, thus, limited.Here, we propose a new approach for estimating functional diversity from a set of hypervolumes. We rely on the concept of occupancy rate, defined as the mean or absolute number of hypervolumes enclosing a given point in the trait space. Furthermore, we describe a permutation test to identify regions of the trait space in which the occupancy rate of two sets of hypervolumes differs.We illustrate the utility of our approach over existing methods with two examples on aquatic macroinvertebrates. The first example shows how occupancy rate relates to the stability of trait space utilisation due to increased flow intermittency and allows the identification of taxa in regions of the trait space with low occupancy rates. The second example shows how the permutation test based on occupancy rates can detect differences in trait space utilisation due to river morphology variation even with a high degree of overlap among input hypervolumes.Our newly developed approach is particularly suitable in functional diversity analysis when investigating patterns of overlap among multiple hypervolumes. We emphasise the need to consider analyses based on occupancy rate into functional diversity estimation. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]