Showing papers by "Swedish University of Agricultural Sciences published in 2019"
McGill University1, WWF-India2, University of Basel3, WWF-Canada4, The Nature Conservancy5, University of Nevada, Reno6, Delft University of Technology7, Konstanz University of Applied Sciences8, King's College London9, Swedish University of Agricultural Sciences10, Umeå University11, University of Washington12, Harvard University13, University of Wisconsin-Madison14, Conservation International15, Michigan Technological University16, Stanford University17, Free University of Berlin18, Leibniz Association19, University of Tübingen20
TL;DR: A comprehensive assessment of the world’s rivers and their connectivity shows that only 37 per cent of rivers longer than 1,000 kilometres remain free-flowing over their entire length.
Abstract: Free-flowing rivers (FFRs) support diverse, complex and dynamic ecosystems globally, providing important societal and economic services. Infrastructure development threatens the ecosystem processes, biodiversity and services that these rivers support. Here we assess the connectivity status of 12 million kilometres of rivers globally and identify those that remain free-flowing in their entire length. Only 37 per cent of rivers longer than 1,000 kilometres remain free-flowing over their entire length and 23 per cent flow uninterrupted to the ocean. Very long FFRs are largely restricted to remote regions of the Arctic and of the Amazon and Congo basins. In densely populated areas only few very long rivers remain free-flowing, such as the Irrawaddy and Salween. Dams and reservoirs and their up- and downstream propagation of fragmentation and flow regulation are the leading contributors to the loss of river connectivity. By applying a new method to quantify riverine connectivity and map FFRs, we provide a foundation for concerted global and national strategies to maintain or restore them. A comprehensive assessment of the world’s rivers and their connectivity shows that only 37 per cent of rivers longer than 1,000 kilometres remain free-flowing over their entire length.
1,071 citations
TL;DR: It is demonstrated that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiome, and this is the first study to report mycorrhizal keystoneTaxa for agroecosystems.
Abstract: Root-associated microbes play a key role in plant performance and productivity, making them important players in agroecosystems. So far, very few studies have assessed the impact of different farming systems on the root microbiota and it is still unclear whether agricultural intensification influences the structure and complexity of microbial communities. We investigated the impact of conventional, no-till, and organic farming on wheat root fungal communities using PacBio SMRT sequencing on samples collected from 60 farmlands in Switzerland. Organic farming harbored a much more complex fungal network with significantly higher connectivity than conventional and no-till farming systems. The abundance of keystone taxa was the highest under organic farming where agricultural intensification was the lowest. We also found a strong negative association (R2 = 0.366; P < 0.0001) between agricultural intensification and root fungal network connectivity. The occurrence of keystone taxa was best explained by soil phosphorus levels, bulk density, pH, and mycorrhizal colonization. The majority of keystone taxa are known to form arbuscular mycorrhizal associations with plants and belong to the orders Glomerales, Paraglomerales, and Diversisporales. Supporting this, the abundance of mycorrhizal fungi in roots and soils was also significantly higher under organic farming. To our knowledge, this is the first study to report mycorrhizal keystone taxa for agroecosystems, and we demonstrate that agricultural intensification reduces network complexity and the abundance of keystone taxa in the root microbiome.
573 citations
ETH Zurich1, University of California, Davis2, Bielefeld University3, Nanyang Technological University4, Wageningen University and Research Centre5, Brigham Young University6, Aligarh Muslim University7, Colorado State University8, University of Manchester9, University of Cologne10, University of La Rioja11, University of Brasília12, Queen's University Belfast13, Nanjing Agricultural University14, University of Minho15, Empresa Brasileira de Pesquisa Agropecuária16, Zealand Institute of Business and Technology17, Spanish National Research Council18, Scotland's Rural College19, American Museum of Natural History20, Russian Academy of Sciences21, Swedish University of Agricultural Sciences22, University of Göttingen23, Chinese Academy of Sciences24, University of Catania25, University of Nebraska–Lincoln26, James Hutton Institute27, Vietnam Academy of Science and Technology28, University of Sydney29, Bulgarian Academy of Sciences30, Universidade Federal de Lavras31, University of Helsinki32, University of Montpellier33, Aarhus University34, Lancaster University35, National Taiwan University36
TL;DR: High-resolution spatial maps of the global abundance of soil nematodes and the composition of functional groups show that soil nematode are found in higher abundances in sub-Arctic regions, than in temperate or tropical regions.
Abstract: Soil organisms are a crucial part of the terrestrial biosphere. Despite their importance for ecosystem functioning, few quantitative, spatially explicit models of the active belowground community currently exist. In particular, nematodes are the most abundant animals on Earth, filling all trophic levels in the soil food web. Here we use 6,759 georeferenced samples to generate a mechanistic understanding of the patterns of the global abundance of nematodes in the soil and the composition of their functional groups. The resulting maps show that 4.4 ± 0.64 × 1020 nematodes (with a total biomass of approximately 0.3 gigatonnes) inhabit surface soils across the world, with higher abundances in sub-Arctic regions (38% of total) than in temperate (24%) or tropical (21%) regions. Regional variations in these global trends also provide insights into local patterns of soil fertility and functioning. These high-resolution models provide the first steps towards representing soil ecological processes in global biogeochemical models and will enable the prediction of elemental cycling under current and future climate scenarios.
552 citations
Günter Blöschl1, Marc F. P. Bierkens2, António Chambel3, Christophe Cudennec4 +209 more•Institutions (124)
TL;DR: In this article, a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts is described. But despite the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work.
Abstract: This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through online media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focused on the process-based understanding of hydrological variability and causality at all space and time scales. Increased attention to environmental change drives a new emphasis on understanding how change propagates across interfaces within the hydrological system and across disciplinary boundaries. In particular, the expansion of the human footprint raises a new set of questions related to human interactions with nature and water cycle feedbacks in the context of complex water management problems. We hope that this reflection and synthesis of the 23 unsolved problems in hydrology will help guide research efforts for some years to come.
469 citations
TL;DR: An overview and practical recommendations for aspects of HTS studies ranging from sampling and laboratory practices to data processing and analysis are provided, and advice for leveraging next-generation technologies to explore mycobiome diversity in different habitats is provided.
Abstract: Fungi are major ecological players in both terrestrial and aquatic environments by cycling organic matter and channelling nutrients across trophic levels. High-throughput sequencing (HTS) studies of fungal communities are redrawing the map of the fungal kingdom by hinting at its enormous - and largely uncharted - taxonomic and functional diversity. However, HTS approaches come with a range of pitfalls and potential biases, cautioning against unwary application and interpretation of HTS technologies and results. In this Review, we provide an overview and practical recommendations for aspects of HTS studies ranging from sampling and laboratory practices to data processing and analysis. We also discuss upcoming trends and techniques in the field and summarize recent and noteworthy results from HTS studies targeting fungal communities and guilds. Our Review highlights the need for reproducibility and public data availability in the study of fungal communities. If the associated challenges and conceptual barriers are overcome, HTS offers immense possibilities in mycology and elsewhere.
461 citations
University of Würzburg1, National University of Comahue2, Spanish National Research Council3, Swedish University of Agricultural Sciences4, Universidade Federal de Goiás5, University of Lisbon6, Stanford University7, Commonwealth Scientific and Industrial Research Organisation8, National University of Río Negro9, ETH Zurich10, Cornell University11, University of California, Davis12, The Nature Conservancy13, Wageningen University and Research Centre14, University of British Columbia15, Great Lakes Bioenergy Research Center16, University of California, Santa Cruz17, University of Padua18, University of New England (Australia)19, Lund University20, University of Göttingen21, Institut national de la recherche agronomique22, University of La Rochelle23, Federal University of Ceará24, University of Freiburg25, Concordia University Wisconsin26, University of Belgrade27, National University of Tucumán28, Michigan State University29, University of Brasília30, University of Greenwich31, University of Reading32, University of Wisconsin-Madison33, National Institute of Amazonian Research34, Boise State University35, University of Texas at Austin36, University of Haifa37, Kansas State University38, University of Hamburg39, Bioversity International40, University of California, Santa Barbara41, Seattle University42, University of Vienna43, University of Florida44, Centro Agronómico Tropical de Investigación y Enseñanza45, National Audubon Society46, University of Buenos Aires47, Virginia Tech48, University of Bordeaux49, University of Auckland50, University of California, Berkeley51, University College Dublin52, Trinity College, Dublin53, University of Tokyo54, Federal University of Bahia55, Lincoln University (New Zealand)56, National Institute for Environmental Studies57, International Food Policy Research Institute58, Xi'an Jiaotong-Liverpool University59
TL;DR: Using a global database from 89 studies (with 1475 locations), the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change is partitioned.
Abstract: Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield-related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.
434 citations
TL;DR: In this article, a comprehensive overview of ecosystem services provided by natural and semi-natural grasslands, using southern Africa (SA) and northwest Europe as case studies, respectively, is presented.
Abstract: Extensively managed grasslands are recognized globally for their high biodiversity and their social and cultural values. However, their capacity to deliver multiple ecosystem services (ES) as parts of agricultural systems is surprisingly understudied compared to other production systems. We undertook a comprehensive overview of ES provided by natural and semi-natural grasslands, using southern Africa (SA) and northwest Europe as case studies, respectively. We show that these grasslands can supply additional non-agricultural services, such as water supply and flow regulation, carbon storage, erosion control, climate mitigation, pollination, and cultural ES. While demand for ecosystems services seems to balance supply in natural grasslands of SA, the smaller areas of semi-natural grasslands in Europe appear to not meet the demand for many services. We identified three bundles of related ES from grasslands: water ES including fodder production, cultural ES connected to livestock production, and population-based regulating services (e.g., pollination and biological control), which also linked to biodiversity. Greenhouse gas emission mitigation seemed unrelated to the three bundles. The similarities among the bundles in SA and northwestern Europe suggest that there are generalities in ES relations among natural and semi-natural grassland areas. We assessed trade-offs and synergies among services in relation to management practices and found that although some trade-offs are inevitable, appropriate management may create synergies and avoid trade-offs among many services. We argue that ecosystem service and food security research and policy should give higher priority to how grasslands can be managed for fodder and meat production alongside other ES. By integrating grasslands into agricultural production systems and land-use decisions locally and regionally, their potential to contribute to functional landscapes and to food security and sustainable livelihoods can be greatly enhanced. (Less)
402 citations
TL;DR: In this paper, the authors present guidelines for the diagnosis and treatment of myxomatous mitral valve disease (MMVD), also known as endocardiosis and degenerative or chronic valvular heart disease in dogs.
Abstract: This report, issued by the ACVIM Specialty of Cardiology consensus panel, revises guidelines for the diagnosis and treatment of myxomatous mitral valve disease (MMVD, also known as endocardiosis and degenerative or chronic valvular heart disease) in dogs, originally published in 2009. Updates were made to diagnostic, as well as medical, surgical, and dietary treatment recommendations. The strength of these recommendations was based on both the quantity and quality of available evidence supporting diagnostic and therapeutic decisions. Management of MMVD before the onset of clinical signs of heart failure has changed substantially compared with the 2009 guidelines, and new strategies to diagnose and treat advanced heart failure and pulmonary hypertension are reviewed.
340 citations
University of Würzburg1, Lund University2, Swedish University of Agricultural Sciences3, Commonwealth Scientific and Industrial Research Organisation4, University of Reading5, Wageningen University and Research Centre6, University of Padua7, University of Rennes8, University of Salamanca9, Agrocampus Ouest10, Sant'Anna School of Advanced Studies11, Spanish National Research Council12, Aix-Marseille University13, University of Kiel14, University of Freiburg15, University of Jyväskylä16, University of Koblenz and Landau17, University of Marburg18, Technische Universität München19, University of Natural Resources and Life Sciences, Vienna20, National University of Río Negro21, Instituto Nacional de Biodiversidad22, University of Giessen23, University of Belgrade24, Institut national de la recherche agronomique25, University of Extremadura26, University of Bordeaux27, University of Bern28, CABI29, University of Göttingen30, Pir Mehr Ali Shah Arid Agriculture University31
TL;DR: In landscapes with high edge density, 70% of pollinator and 44% of natural enemy species reached highest abundances and pollination and pest control improved 1.7- and 1.4-fold respectively, suggesting that enhancing edge density in European agroecosystems can promote functional biodiversity and yield-enhancing ecosystem services.
Abstract: Managing agricultural landscapes to support biodiversity and ecosystem services is a key aim of a sustainable agriculture. However, how the spatial arrangement of crop fields and other habitats in landscapes impacts arthropods and their functions is poorly known. Synthesising data from 49 studies (1515 landscapes) across Europe, we examined effects of landscape composition (% habitats) and configuration (edge density) on arthropods in fields and their margins, pest control, pollination and yields. Configuration effects interacted with the proportions of crop and non-crop habitats, and species’ dietary, dispersal and overwintering traits led to contrasting responses to landscape variables. Overall, however, in landscapes with high edge density, 70% of pollinator and 44% of natural enemy species reached highest abundances and pollination and pest control improved 1.7- and 1.4-fold respectively. Arable-dominated landscapes with high edge densities achieved high yields. This suggests that enhancing edge density in European agroecosystems can promote functional biodiversity and yield-enhancing ecosystem services.
321 citations
TL;DR: In this article, the main treatment factors found to be affected by substrate were waste-to-biomass conversion ratio, larval development time and final prepupal weight.
316 citations
TL;DR: It is shown that fungicides occur widely in aquatic systems, that the accuracy of predicted environmental concentrations is debatable, and that fungicide exposure can be effectively mitigated, andThat fungicides can be highly toxic to a broad range of organisms and can pose a risk to aquatic biota.
Abstract: Fungicides are indispensable to global food security and their use is forecasted to intensify. Fungicides can reach aquatic ecosystems and occur in surface water bodies in agricultural catchments throughout the entire growing season due to their frequent, prophylactic application. However, in comparison to herbicides and insecticides, the exposure to and effects of fungicides have received less attention. We provide an overview of the risk of fungicides to aquatic ecosystems covering fungicide exposure (i.e., environmental fate, exposure modeling, and mitigation measures) as well as direct and indirect effects of fungicides on microorganisms, macrophytes, invertebrates, and vertebrates. We show that fungicides occur widely in aquatic systems, that the accuracy of predicted environmental concentrations is debatable, and that fungicide exposure can be effectively mitigated. We additionally demonstrate that fungicides can be highly toxic to a broad range of organisms and can pose a risk to aquatic biota. Finally, we outline central research gaps that currently challenge our ability to predict fungicide exposure and effects, promising research avenues, and shortcomings of the current environmental risk assessment for fungicides.
TL;DR: A review of the evidence for replacing external inputs with ecosystem services shows that scientists tend to focus on processes rather than outcomes, and express benefits at spatio-temporal scales that are not always relevant to farmers, resulting in mismatches in perceived benefits of ecological intensification between scientists and farmers, which hinders its uptake.
Abstract: There is worldwide concern about the environmental costs of conventional intensification of agriculture. Growing evidence suggests that ecological intensification of mainstream farming can safeguard food production, with accompanying environmental benefits; however, the approach is rarely adopted by farmers. Our review of the evidence for replacing external inputs with ecosystem services shows that scientists tend to focus on processes (e.g., pollination) rather than outcomes (e.g., profits), and express benefits at spatio-temporal scales that are not always relevant to farmers. This results in mismatches in perceived benefits of ecological intensification between scientists and farmers, which hinders its uptake. We provide recommendations for overcoming these mismatches and highlight important additional factors driving uptake of nature-based management practices, such as social acceptability of farming.
Wageningen University and Research Centre1, Humboldt State University2, Katholieke Universiteit Leuven3, Agricultural & Applied Economics Association4, Leibniz Association5, University of Gloucestershire6, Polish Academy of Sciences7, University of Bergen8, Aberystwyth University9, Swedish University of Agricultural Sciences10, Université Paris-Saclay11, Tuscia University12, Technical University of Madrid13, University of National and World Economy14
TL;DR: In this paper, the authors define resilience of a farming system as its ability to ensure the provision of the system functions in the face of increasingly complex and accumulating economic, social, environmental and institutional shocks and stresses, through capacities of robustness, adaptability and transformability.
University of Duisburg-Essen1, Slovak Academy of Sciences2, University of Minho3, University of Pécs4, Leibniz Association5, Hong Kong Environmental Protection Department6, University of Savoy7, Swedish University of Agricultural Sciences8, Naturhistorisches Museum9, University of Bergen10, University of Porto11, Naturalis12, University of Salzburg13, University of Natural Resources and Life Sciences, Vienna14, Bielefeld University15, Ilia State University16, Babeș-Bolyai University17, Ankara University18, National Institute of Oceanography, India19, University of Montenegro20, American Museum of Natural History21, Norwegian University of Science and Technology22
TL;DR: This work analysed gaps in the two most important reference databases, Barcode of Life Data Systems (BOLD) and NCBI GenBank, with a focus on the taxa most frequently used in WFD and MSFD, and found that coverage varies strongly among taxonomic groups, and among geographic regions.
University of Helsinki1, Norwegian University of Science and Technology2, Université de Sherbrooke3, University of Utah4, Landcare Research5, Spanish National Research Council6, University of Évora7, University of Copenhagen8, Duke University9, University of Melbourne10, Commonwealth Scientific and Industrial Research Organisation11, Butterfly Conservation12, University of California, Riverside13, Lincoln University (New Zealand)14, University of Lausanne15, University of Tasmania16, University of Florida17, Australian National University18, Nord University19, American Museum of Natural History20, Arthur Rylah Institute for Environmental Research21, University of Newcastle22, Swedish University of Agricultural Sciences23, University of Grenoble24, University of New South Wales25
TL;DR: This work compared the predictive performance of 33 variants of 15 widely applied and recently emerged species distribution model approaches in the context of multispecies data, including both joint SDMs that model multiple species together, and stacked SDM that model each species individually combining the predictions afterward.
Abstract: A large array of species distribution model (SDM) approaches has been developed for explaining and predicting the occurrences of individual species or species assemblages. Given the wealth of existing models, it is unclear which models perform best for interpolation or extrapolation of existing data sets, particularly when one is concerned with species assemblages. We compared the predictive performance of 33 variants of 15 widely applied and recently emerged SDMs in the context of multispecies data, including both joint SDMs that model multiple species together, and stacked SDMs that model each species individually combining the predictions afterward. We offer a comprehensive evaluation of these SDM approaches by examining their performance in predicting withheld empirical validation data of different sizes representing five different taxonomic groups, and for prediction tasks related to both interpolation and extrapolation. We measure predictive performance by 12 measures of accuracy, discrimination power, calibration, and precision of predictions, for the biological levels of species occurrence, species richness, and community composition. Our results show large variation among the models in their predictive performance, especially for communities comprising many species that are rare. The results do not reveal any major trade‐offs among measures of model performance; the same models performed generally well in terms of accuracy, discrimination, and calibration, and for the biological levels of individual species, species richness, and community composition. In contrast, the models that gave the most precise predictions were not well calibrated, suggesting that poorly performing models can make overconfident predictions. However, none of the models performed well for all prediction tasks. As a general strategy, we therefore propose that researchers fit a small set of models showing complementary performance, and then apply a cross‐validation procedure involving separate data to establish which of these models performs best for the goal of the study.
Hebei University1, Henan University2, Peking University3, Chinese Academy of Sciences4, Colorado State University5, University of Vermont6, University of Antwerp7, University of Tasmania8, Auckland University of Technology9, University of Copenhagen10, Swedish University of Agricultural Sciences11, East China Normal University12, Northern Arizona University13, Villanova University14, ETH Zurich15, University of Bern16, Purdue University17, Marine Biological Laboratory18, Michigan State University19, Iowa State University20, Environmental Molecular Sciences Laboratory21, University of California, Berkeley22, Lawrence Berkeley National Laboratory23, United States Department of Agriculture24, Boston University25, Virginia Tech26, Oak Ridge National Laboratory27, Indiana University28, Commonwealth Scientific and Industrial Research Organisation29, Binzhou University30
TL;DR: There is an urgent need to explore the interactions among multiple global change drivers in underrepresented regions such as semi-arid ecosystems, forests in the tropics and subtropics, and Arctic tundra when forecasting future terrestrial carbon-climate feedback.
Abstract: Direct quantification of terrestrial biosphere responses to global change is crucial for projections of future climate change in Earth system models. Here, we synthesized ecosystem carbon-cycling data from 1,119 experiments performed over the past four decades concerning changes in temperature, precipitation, CO2 and nitrogen across major terrestrial vegetation types of the world. Most experiments manipulated single rather than multiple global change drivers in temperate ecosystems of the USA, Europe and China. The magnitudes of warming and elevated CO2 treatments were consistent with the ranges of future projections, whereas those of precipitation changes and nitrogen inputs often exceeded the projected ranges. Increases in global change drivers consistently accelerated, but decreased precipitation slowed down carbon-cycle processes. Nonlinear (including synergistic and antagonistic) effects among global change drivers were rare. Belowground carbon allocation responded negatively to increased precipitation and nitrogen addition and positively to decreased precipitation and elevated CO2. The sensitivities of carbon variables to multiple global change drivers depended on the background climate and ecosystem condition, suggesting that Earth system models should be evaluated using site-specific conditions for best uses of this large dataset. Together, this synthesis underscores an urgent need to explore the interactions among multiple global change drivers in underrepresented regions such as semi-arid ecosystems, forests in the tropics and subtropics, and Arctic tundra when forecasting future terrestrial carbon-climate feedback.
University of Würzburg1, National University of Comahue2, Spanish National Research Council3, Swedish University of Agricultural Sciences4, Universidade Federal de Goiás5, University of Lisbon6, Stanford University7, Commonwealth Scientific and Industrial Research Organisation8, National University of Río Negro9, ETH Zurich10, Cornell University11, University of California, Davis12, The Nature Conservancy13, Wageningen University and Research Centre14, University of British Columbia15, Great Lakes Bioenergy Research Center16, University of California, Berkeley17, University of Padua18, University of New England (United States)19, Lund University20, University of Göttingen21, University of La Rochelle22, Institut national de la recherche agronomique23, Federal University of Ceará24, Concordia University Wisconsin25, University of Belgrade26, National University of Tucumán27, Michigan State University28, University of Brasília29, University of Greenwich30, University of Reading31, University of Wisconsin-Madison32, Boise State University33, University of Texas at Austin34, University of Haifa35, Kansas State University36, University of Freiburg37, University of Hamburg38, University of California, Santa Barbara39, Seattle University40, University of Vienna41, University of Florida42, Centro Agronómico Tropical de Investigación y Enseñanza43, National Audubon Society44, University of Buenos Aires45, Virginia Tech46, University of Bordeaux47, University of Auckland48, University College Dublin49, Trinity College, Dublin50, University of Tokyo51, Federal University of Bahia52, Lincoln University (Pennsylvania)53, National Institute for Environmental Studies54, International Food Policy Research Institute55, Xi'an Jiaotong-Liverpool University56
TL;DR: Using a global database from 89 crop systems, the relative importance of abundance and species richness for pollination, biological pest control and final yields in the context of on-going land-use change is partitioned.
Abstract: Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield-related ecosystem services can be maintained by few abundant species or rely on high richness remains unclear. Using a global database from 89 crop systems, we partition the relative importance of abundance and species richness for pollination, biological pest control and final yields in the context of on-going land-use change. Pollinator and enemy richness directly supported ecosystem services independent of abundance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.
TL;DR: In this article, the authors used a 19-year plant functional group removal experiment across a long term post-fire chronosequence to assess how microbial community structure (assessed using phospholipids fatty acids; PLFAs) and the association of bacterial functional groups (specifically, the GP:GN ratio) responded to changes in organic matter chemistry.
Abstract: Despite recent progress in understanding soil microbial responses to carbon (C) limitation, the functional shifts in microbial community structure associated with decreasing soil C availability and changes in organic matter chemistry remain poorly known. It has been proposed that Gram-negative (GN) bacteria use more plant-derived C sources that are relatively labile, while Gram-positive (GP) bacteria use C sources derived from soil organic matter that are more recalcitrant. Because these two groups may differ in how they influence the fate of different C forms in soils, it is important to understand how they vary across ecosystems that differ in their vegetation cover and ecosystem productivity or across environmental gradients. In this study, we used a 19-year plant functional group removal experiment across a long term post-fire chronosequence to assess how microbial community structure (assessed using phospholipids fatty acids; PLFAs) and the association of bacterial functional groups (specifically, the GP:GN ratio) responded to changes in organic matter chemistry (measured via nuclear magnetic resonance; NMR). We found that the GP:GN ratio increased upon removal of shrubs and tree roots and with decreasing ecosystem productivity along the chronosequence, thus showing the greater dependence of GN than GP bacteria on more labile plant-derived C. Overall, GN bacteria were associated with simple C compounds (alkyls) whereas GP bacteria were more strongly associated with more complex C forms (carbonyls). Therefore, we conclude that the GP:GN ratio has potential as a useful indicator of the relative C availability for soil bacterial communities in organic soils, and can be used as a coarse indicator of energy limitation in natural ecosystems.
Brigham Young University1, Uppsala University2, Michigan State University3, University of Alaska Fairbanks4, Idaho State University5, Virginia Tech6, Institut de Physique du Globe de Paris7, Swedish University of Agricultural Sciences8, University of Waterloo9, Agrocampus Ouest10, Water Research Foundation11
TL;DR: In this paper, the authors present a synthesis of the global water cycle, which they compared with 464 water cycle diagrams from around the world, finding that only 15% of the diagrams depicted human interaction with water.
Abstract: Human water use, climate change and land conversion have created a water crisis for billions of individuals and many ecosystems worldwide. Global water stocks and fluxes are estimated empirically and with computer models, but this information is conveyed to policymakers and researchers through water cycle diagrams. Here we compiled a synthesis of the global water cycle, which we compared with 464 water cycle diagrams from around the world. Although human freshwater appropriation now equals half of global river discharge, only 15% of the water cycle diagrams depicted human interaction with water. Only 2% of the diagrams showed climate change or water pollution—two of the central causes of the global water crisis—which effectively conveys a false sense of water security. A single catchment was depicted in 95% of the diagrams, which precludes the representation of teleconnections such as ocean–land interactions and continental moisture recycling. These inaccuracies correspond with specific dimensions of water mismanagement, which suggest that flaws in water diagrams reflect and reinforce the misunderstanding of global hydrology by policymakers, researchers and the public. Correct depictions of the water cycle will not solve the global water crisis, but reconceiving this symbol is an important step towards equitable water governance, sustainable development and planetary thinking in the Anthropocene.
Louisiana State University1, University of Cambridge2, University of Bath3, University of Minnesota4, Museu Paraense Emílio Goeldi5, University of New Mexico6, Chinese Academy of Sciences7, Uppsala University8, Swedish University of Agricultural Sciences9, American Museum of Natural History10, University of Michigan11, University of Florida12, Smithsonian Institution13, University of Maryland, College Park14, University of São Paulo15, Harvard University16, National Museum of Natural History17, Royal Ontario Museum18, University of Toronto19, National University of Colombia20, University of Tennessee21, University of Georgia22, University of Copenhagen23, Commonwealth Scientific and Industrial Research Organisation24, Pennsylvania State University25, Museum of New Zealand Te Papa Tongarewa26, University of Kansas27
TL;DR: Recon reconstructing passerine evolutionary history and producing the most comprehensive time-calibrated phylogenetic hypothesis of the group, which suggests more complex mechanisms than temperature change or ecological opportunity have controlled macroscale patterns of passerine speciation.
Abstract: Avian diversification has been influenced by global climate change, plate tectonic movements, and mass extinction events. However, the impact of these factors on the diversification of the hyperdiverse perching birds (passerines) is unclear because family level relationships are unresolved and the timing of splitting events among lineages is uncertain. We analyzed DNA data from 4,060 nuclear loci and 137 passerine families using concatenation and coalescent approaches to infer a comprehensive phylogenetic hypothesis that clarifies relationships among all passerine families. Then, we calibrated this phylogeny using 13 fossils to examine the effects of different events in Earth history on the timing and rate of passerine diversification. Our analyses reconcile passerine diversification with the fossil and geological records; suggest that passerines originated on the Australian landmass ∼47 Ma; and show that subsequent dispersal and diversification of passerines was affected by a number of climatological and geological events, such as Oligocene glaciation and inundation of the New Zealand landmass. Although passerine diversification rates fluctuated throughout the Cenozoic, we find no link between the rate of passerine diversification and Cenozoic global temperature, and our analyses show that the increases in passerine diversification rate we observe are disconnected from the colonization of new continents. Taken together, these results suggest more complex mechanisms than temperature change or ecological opportunity have controlled macroscale patterns of passerine speciation.
United States Department of Agriculture1, University of Pretoria2, University of Montpellier3, University of Georgia4, Swedish University of Agricultural Sciences5, ANSES6, Animal and Plant Health Agency7, South Dakota State University8, Australian Animal Health Laboratory9, University of São Paulo10, Friedrich Loeffler Institute11, Animal and Plant Health Inspection Service12, Royal Veterinary College13, Northwest A&F University14, Lancaster University15, Ministry of Agriculture16, South Valley University17, Virginia–Maryland Regional College of Veterinary Medicine18
TL;DR: An updated NDV classification and nomenclature system that incorporates phylogenetic topology, genetic distances, branch support, and epidemiological independence was developed and will facilitate future studies of NDV evolution and epidemiology, and comparison of results obtained across the world.
TL;DR: In this paper, the authors use historical records of harvester and tractor weights to simulate how the weight increase has changed soil stresses and bulk density of arable soil, and to predict impacts on the mechanical resistance for root growth and on soil hydraulic properties.
Abstract: Soil compaction caused by vehicular traffic adversely affects key soil functions and ecosystem services that soils provide. Although compaction is a well-recognized problem, it remains challenging to quantify the economic and ecological costs of compaction. The mechanization in agriculture has resulted in a steady increase in weight of farm vehicles. It is reasonable to assume that this has exacerbated soil compaction, but there is little quantitative knowledge on the development of compaction levels in arable soils. To quantify these trends, we use historical records of harvester and tractor weights to simulate how the weight increase has changed soil stresses and bulk density of arable soil, and to predict impacts on the mechanical resistance for root growth and on soil hydraulic properties. Our simulations show a clear increase in soil stress levels with higher bulk density and mechanical penetration resistance, and a decrease in soil hydraulic conductivity in agreement with available data. We show that increased mechanical resistance has resulted in decreased root elongation rates and consequently prolonged the time required for roots to reach a certain soil depth. The historical changes of compaction levels and associated limitations on root elongation rates coincide with a stagnation in crop yields in the 1990s observed for cereals in many countries. Our calculations illustrate that the historical increase in compaction levels has drastically decreased saturated hydraulic conductivity and water storage capacity of subsoils. We speculate that this has contributed to the increase in the incidence and severity of flood events during recent decades in Europe. Finally, we take Sweden as an example and estimate annual compaction costs due to agricultural productivity loss and flooding damage of several hundred M€ yr−1 for Sweden. Considering the continuation of upwards trends in the average weight of farm machinery and the projected increase in extreme weather events, the costs of soil compaction are likely to escalate. The study highlights that we have likely exceeded the acceptable loads, and that future agricultural operations must consider the inherent mechanical limit of soil.
TL;DR: The heritable core microbes, therefore, present primary targets for rumen manipulation toward sustainable and environmentally friendly agriculture.
Abstract: A 1000-cow study across four European countries was undertaken to understand to what extent ruminant microbiomes can be controlled by the host animal and to identify characteristics of the host rumen microbiome axis that determine productivity and methane emissions. A core rumen microbiome, phylogenetically linked and with a preserved hierarchical structure, was identified. A 39-member subset of the core formed hubs in co-occurrence networks linking microbiome structure to host genetics and phenotype (methane emissions, rumen and blood metabolites, and milk production efficiency). These phenotypes can be predicted from the core microbiome using machine learning algorithms. The heritable core microbes, therefore, present primary targets for rumen manipulation toward sustainable and environmentally friendly agriculture.
University of Helsinki1, Nara Institute of Science and Technology2, University of Cambridge3, Osaka University4, University of Nottingham5, Wageningen University and Research Centre6, Ghent University7, Nara Women's University8, Heidelberg University9, University of Tokyo10, Swedish University of Agricultural Sciences11, North Carolina State University12
TL;DR: During root procambial development there exists a network in which a module that links PEAR and HD-ZIP III transcription factors integrates spatial information of the hormonal domains and miRNA gradients to provide adjacent zones of dividing and more-quiescent cells, which forms a foundation for further radial growth.
Abstract: Apical growth in plants initiates upon seed germination, whereas radial growth is primed only during early ontogenesis in procambium cells and activated later by the vascular cambium1. Although it is not known how radial growth is organized and regulated in plants, this system resembles the developmental competence observed in some animal systems, in which pre-existing patterns of developmental potential are established early on2,3. Here we show that in Arabidopsis the initiation of radial growth occurs around early protophloem-sieve-element cell files of the root procambial tissue. In this domain, cytokinin signalling promotes the expression of a pair of mobile transcription factors—PHLOEM EARLY DOF 1 (PEAR1) and PHLOEM EARLY DOF 2 (PEAR2)—and their four homologues (DOF6, TMO6, OBP2 and HCA2), which we collectively name PEAR proteins. The PEAR proteins form a short-range concentration gradient that peaks at protophloem sieve elements, and activates gene expression that promotes radial growth. The expression and function of PEAR proteins are antagonized by the HD-ZIP III proteins, well-known polarity transcription factors4—the expression of which is concentrated in the more-internal domain of radially non-dividing procambial cells by the function of auxin, and mobile miR165 and miR166 microRNAs. The PEAR proteins locally promote transcription of their inhibitory HD-ZIP III genes, and thereby establish a negative-feedback loop that forms a robust boundary that demarks the zone of cell division. Taken together, our data establish that during root procambial development there exists a network in which a module that links PEAR and HD-ZIP III transcription factors integrates spatial information of the hormonal domains and miRNA gradients to provide adjacent zones of dividing and more-quiescent cells, which forms a foundation for further radial growth. Radial growth in the roots of Arabidopsis, which is mediated by gene expression activated by the mobile PEAR1 and PEAR2 transcription factors, is initiated around protophloem-sieve-element cell files of procambial tissue.
TL;DR: It is indicated that olfactory stimuli may be better at facilitating stress reduction than visual stimuli and currently, urban planners prioritise visual stimuli when planning open green spaces, but urban planners should also consider multisensory qualities.
Abstract: Although stress is an increasing global health problem in cities, urban green spaces can provide health benefits. There is, however, a lack of understanding of the link between physiological mechanisms and qualities of urban green spaces. Here, we compare the effects of visual stimuli (360 degree virtual photos of an urban environment, forest, and park) to the effects of congruent olfactory stimuli (nature and city odours) and auditory stimuli (bird songs and noise) on physiological stress recovery. Participants (N = 154) were pseudo-randomised into participating in one of the three environments and subsequently exposed to stress (operationalised by skin conductance levels). The park and forest, but not the urban area, provided significant stress reduction. High pleasantness ratings of the environment were linked to low physiological stress responses for olfactory and to some extent for auditory, but not for visual stimuli. This result indicates that olfactory stimuli may be better at facilitating stress reduction than visual stimuli. Currently, urban planners prioritise visual stimuli when planning open green spaces, but urban planners should also consider multisensory qualities.
TL;DR: In this paper, the authors have shown that vanadium is a redox-sensitive element, which occurs in three oxidation states (+III, +IV and +V) in the environment.
University of Sydney1, State University of New York System2, University of North Florida3, Hobart Corporation4, Michigan Technological University5, James Cook University6, University of California, Berkeley7, University of New South Wales8, Unity College9, University of Lorraine10, Tohoku University11, Linnaeus University12, University of Washington13, University of Wisconsin-Madison14, University of Exeter15, Kyoto University16, University of Minnesota17, Brookhaven National Laboratory18, Smithsonian Tropical Research Institute19, Texas Tech University20, University of Gothenburg21, Swedish University of Agricultural Sciences22, Macquarie University23, Federal University of Western Pará24, Oak Ridge National Laboratory25, Duke University26, University of Western Ontario27
TL;DR: A summary model to represent photosynthetic temperature responses was developed and showed that it predicted the observed global variation in optimal temperatures with high accuracy, which should enable improved prediction of the function of global ecosystems in a warming climate.
Abstract: The temperature response of photosynthesis is one of the key factors determining predicted responses to warming in global vegetation models (GVMs). The response may vary geographically, owing to genetic adaptation to climate, and temporally, as a result of acclimation to changes in ambient temperature. Our goal was to develop a robust quantitative global model representing acclimation and adaptation of photosynthetic temperature responses. We quantified and modelled key mechanisms responsible for photosynthetic temperature acclimation and adaptation using a global dataset of photosynthetic CO2 response curves, including data from 141 C3 species from tropical rainforest to Arctic tundra. We separated temperature acclimation and adaptation processes by considering seasonal and common-garden datasets, respectively. The observed global variation in the temperature optimum of photosynthesis was primarily explained by biochemical limitations to photosynthesis, rather than stomatal conductance or respiration. We found acclimation to growth temperature to be a stronger driver of this variation than adaptation to temperature at climate of origin. We developed a summary model to represent photosynthetic temperature responses and showed that it predicted the observed global variation in optimal temperatures with high accuracy. This novel algorithm should enable improved prediction of the function of global ecosystems in a warming climate.
TL;DR: It is concluded that protists form an essential component of the rhizosphere microbiome and that accounting for predator-prey interactions would greatly improve the ability to predict and manage microbiome function at the service of plant growth and health.
University of Porto1, University of Valencia2, Charles University in Prague3, Uppsala University4, University of Pavia5, Lund University6, Czech University of Life Sciences Prague7, University of L'Aquila8, University of Tasmania9, University of Oxford10, Texas A&M University11, Swedish University of Agricultural Sciences12
TL;DR: The genomes of sympatric color morphs of the European common wall lizard (Podarcis muralis), which differ in orange and yellow pigmentation and in their ecology and behavior, are virtually undifferentiated.
Abstract: Reptiles use pterin and carotenoid pigments to produce yellow, orange, and red colors. These conspicuous colors serve a diversity of signaling functions, but their molecular basis remains unresolved. Here, we show that the genomes of sympatric color morphs of the European common wall lizard (Podarcis muralis), which differ in orange and yellow pigmentation and in their ecology and behavior, are virtually undifferentiated. Genetic differences are restricted to two small regulatory regions near genes associated with pterin [sepiapterin reductase (SPR)] and carotenoid [beta-carotene oxygenase 2 (BCO2)] metabolism, demonstrating that a core gene in the housekeeping pathway of pterin biosynthesis has been coopted for bright coloration in reptiles and indicating that these loci exert pleiotropic effects on other aspects of physiology. Pigmentation differences are explained by extremely divergent alleles, and haplotype analysis revealed abundant transspecific allele sharing with other lacertids exhibiting color polymorphisms. The evolution of these conspicuous color ornaments is the result of ancient genetic variation and cross-species hybridization.