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Diet diversity and pesticide risk mediate the negative effects of land use change on solitary bee offspring production
Threats to bee pollinators such as land use change, high pesticide risk and reduced floral diet diversity are usually assessed independently, even though they often co-occur to impact bees in agroecosystems. We established populations of the non-native mason bee Osmia cornifrons at 17 NY apple orchards varying in proportion of surrounding agriculture and measured floral diet diversity and pesticide risk levels in the pollen provisions they produced. We used path analysis to test the direct and indirect effects of different habitats, diet diversity and pesticide risk on emergent female offspring number and weight. High proportions of agricultural habitat surrounding bee nests indirectly reduced the number of female offspring produced, by reducing floral diet diversity in pollen. When the proportion of agriculture surrounding bee nests was high, bees collected increased proportions of Rosaceae in their pollen provisions, which marginally (0.05 < p < 0.1) increased fungicide risk levels in pollen. This, in turn, marginally reduced female offspring weight. In contrast, female offspring weight increased as proportions surrounding open habitat (wildflowers, grassland and pasture) increased, but this effect was not influenced by proportion Rosaceae or fungicide risk levels in pollen. Synthesis and applications. Threats to bee health such as land use change, pesticide exposure and changes in pollen diet composition are often studied in isolation. However, our results suggest that these threats can simultaneously influence one another to impact bee populations in the agroecosystems where we rely on them for pollination. By replacing surrounding agricultural habitats with more natural habitats, such as grasslands and pastures, we can increase floral diet diversity and reduce pesticide exposure in bee-collected pollen, resulting in healthier mason bee populations in apple orchards.</p
Evolution of lifestyles in Capnodiales
The Capnodiales, which includes fungi known as the sooty moulds, represents the second largest order in Dothideomycetes, encompassing morphologically and ecologically diverse fungi with different lifestyles and modes of nutrition. They include saprobes, plant and human pathogens, mycoparasites, rock-inhabiting fungi (RIF), lichenised, epi-, ecto- and endophytes. The aim of this study was to elucidate the lifestyles and evolutionary patterns of the Capnodiales as well as to reconsider their phylogeny by including numerous new collections of sooty moulds, and using four nuclear loci, LSU, ITS, TEF-1α and RPB2. Based on the phylogenetic results, combined with morphology and ecology, Capnodiales s. lat. is shown to be polyphyletic, representing seven different orders. The sooty moulds are restricted to Capnodiales s. str., while Mycosphaerellales is resurrected, and five new orders including Cladosporiales, Comminutisporales, Neophaeothecales, Phaeothecales and Racodiales are introduced. Four families, three genera, 21 species and five combinations are introduced as new. Furthermore, ancestral reconstruction analysis revealed that the saprobic lifestyle is a primitive state in Capnodiales s. lat., and that several transitions have occurred to evolve lichenised, plant and human parasitic, ectophytic (sooty blotch and flyspeck) and more recently epiphytic (sooty mould) lifestyles.</p
Towards an anticipatory public engagement methodology : deliberative experiments in the assembly of possible worlds using focus groups
Against the background of critique in public engagement scholarship on new and emerging science and innovation, this article engages with the methodological and conceptual challenges of making anticipatory knowledge. Adopting a science and technology studies perspective, a public engagement methodology is presented aimed at anticipating the kinds of possible and plausible worlds that novel science and technology bring into being. Drawing on six empirical social science research projects using focus groups, design criteria are explicated on context, framing, moderation, sampling, analysis and interpretation. A feature of the methodology lies in the assembly of emergent collectives and identities that are constituted to negotiate endogenously public meanings, concerns and priorities. I reflect on the potential of such processes to reconfigure dominant policy narratives, the role of the social scientist in mediating such processes and the politics of making anticipatory knowledge.</p
Philosophy of Ethnobiology : Understanding Knowledge Integration and Its Limitations
Ethnobiology has become increasingly concerned with applied and normative issues, such as climate change adaptation, forest management, and sustainable agriculture. Applied ethnobiology emphasizes the practical importance of local and traditional knowledge in tackling these issues but thereby also raises complex theoretical questions about the integration of heterogeneous knowledge systems. The aim of this article is to develop a framework for addressing questions of integration through four core domains of philosophy - epistemology, ontology, value theory, and political theory. In each of these dimensions, we argue for a model of "partial overlaps" that acknowledges both substantial similarities and differences between knowledge systems. While overlaps can ground successful collaboration, their partiality requires reflectivity about the limitations of collaboration and co-creation. By outlining such a general and programmatic framework, the article aims to contribute to developing "philosophy of ethnobiology" as a field of interdisciplinary exchange that provides new resources for addressing foundational issues in ethnobiology and also expands the agenda of philosophy of biology.</p
Mapping the life cycle co-creation process of nature-based solutions for urban climate change adaptation
Developing urban and peri-urban ecosystem services with nature-based solutions (NBS) and participatory approaches can help achieve more resilient and sustainable environments for cities and urban areas in the face of climate change. The co-creation process is increasingly recognised as the way forward to deal with environmental issues in cities, allowing the development of associated methods and tools that have been described and published for specific stages. It is argued that the co-creation process comprises various interlinked stages, corresponding stakeholders, and subsequent methods and tools that need to be mapped and integrated across all stages. In this study, a Life Cycle Co-Creation Process (LCCCP) for NBS is developed, building on continuous improvement cycles and Design Thinking methodologies, and for which the stages and substages, involved stakeholders and engagement methods and tools are mapped and defined. For stakeholders, the actors of an Urban Living Lab (ULL) are adapted to the LCCCP; for the engagement methods and tools, the goals of stakeholder engagement are used as a guide to select examples of co-creation methods and tools. The developed LCCCP comprises five stages, i.e., CoExplore, CoDesign, CoExperiment, CoImplement and CoManagement, creating a unique path that can be followed by practitioners for NBS co-creation.</p
Leidraad beheersing eikenprocessierups uitgebracht: De EPR
Vorig jaar hebben we ervaren dat de eikenprocessierups onze gezondheid en ons welbevinden aanzienlijk kan schaden. Wat is een effectieve aanpak om de overlast te beheersen zonder onnodig hoge beheerkosten te maken? De ‘Leidraad beheersing eikenprocessierups’ die onlangs werd uitgebracht, geeft antwoorden
Plastome phylogeography in two African rain forest legume trees reveals that Dahomey Gap populations originate from the Cameroon volcanic line
Paleo-environmental data show that the distribution of African rain forests was affected by Quaternary climate changes. In particular, the Dahomey Gap (DG) – a 200 km wide savanna corridor currently separating the West African and Central African rain forest blocks and containing relict rain forest fragments – was forested during the mid-Holocene and possibly during previous interglacial periods, whereas it was dominated by open vegetation (savanna) during glacial periods. Genetic signatures of past population fragmentation and demographic changes have been found in some African forest plant species using nuclear markers, but such events appear not to have been synchronous or shared across species. To better understand the colonization history of the DG by rain forest trees through seed dispersal, the plastid genomes of two widespread African forest legume trees, Anthonotha macrophylla and Distemonanthus benthamianus, were sequenced in 47 individuals for each species, providing unprecedented phylogenetic resolution of their maternal lineages (857 and 115 SNPs, respectively). Both species exhibit distinct lineages separating three regions: 1. Upper Guinea (UG, i.e. the West African forest block), 2. the area ranging from the DG to the Cameroon volcanic line (CVL), and 3. Lower Guinea (LG, the western part of the Central African forest block) where three lineages co-occur. In both species, the DG populations (including southern Nigeria west of Cross River) exhibit much lower genetic diversity than UG and LG populations, and their plastid lineages originate from the CVL, confirming the role of the CVL as an ancient forest refuge. Despite the similar phylogeographic structures displayed by A. macrophylla and D. benthamianus, molecular dating indicates very contrasting ages of lineage divergence (UG diverged from LG since c. 7 Ma and 0.7 Ma, respectively) and DG colonization (probably following the Mid Pleistocene Transition and the Last Glacial Maximum, respectively). The stability of forest refuge areas and repeated similar forest shrinking/expanding events during successive glacial periods might explain why similar phylogeographic patterns can be generated over contrasting timescales.</p
Community-based governance : Implications for ecosystem service supply in Berg en Dal, the Netherlands
Governance is an essential element in land-use decision-making and ecosystem management choices and thus for ecosystem service provisioning. Although a community-based approach, i.e. governance involving actors from all spheres of society (the state, market and civil society), is considered most appropriate for natural resource management, there is a lack of knowledge about its actual effects on environmental outcomes and ecosystem service supply in particular. To obtain insight in the effect of governance on ecosystem service provision in our study region (Berg en Dal, the Netherlands), we constructed ecosystem service maps for the period 1995 to 2012 using land-use maps. Also an inventory of the implemented governance models was created, based on interviews with stakeholders, supplemented with literature research. Our results show that 1) governance in Berg en Dal changed from top-down to more community-based models during the studied period; and 2) that the potential and actual supply of the majority of the investigated regulating, cultural and habitat ecosystem services increased during the studied period, at the expense of agricultural production. The interviewed local stakeholders also indicated that they have the perception that the landscape has improved during the last two decades. Although there is a clear connection between governance and improved ecosystem service supply, more research is needed to further develop causal relationships explaining the indirect effects and non-linear behavior within ecosystem service governance systems.</p