113 research outputs found

    Moderation is best: Effects of grazing intensity on plant-flower visitor networks in Mediterranean communities

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    The structure of pollination networks is an important indicator of ecosystem stability and functioning. Livestock grazing is a frequent land use practice that directly affects the abundance and diversity of flowers and pollinators and, therefore, may indirectly affect the structure of pollination networks. We studied how grazing intensity affected the structure of plant-flower visitor networks along a wide range of grazing intensities by sheep and goats, using data from 11 Mediterranean plant-flower visitor communities from Lesvos Island, Greece. We hypothesized that intermediate grazing might result in higher diversity as predicted by the Intermediate Disturbance Hypothesis, which could in turn confer more stability to the networks. Indeed, we found that networks at intermediate grazing intensities were larger, more generalized, more modular, and contained more diverse and even interactions. Despite general responses at the network level, the number of interactions and selectiveness of particular flower visitor and plant taxa in the networks responded differently to grazing intensity, presumably as a consequence of variation in the abundance of different taxa with grazing. Our results highlight the benefit of maintaining moderate levels of livestock grazing by sheep and goats to preserve the complexity and biodiversity of the rich Mediterranean communities, which have a long history of grazing by these domestic animals.The research has been co-financed by the European Union (European Social Fund—ESF) and Greek National funds through the Operational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF)—Research Funding Program: THALES: Investing in knowledge society through the European Social FundPeer Reviewe

    Deux nouvelles espĂšces du genre Merodon Meigen 1803 (Diptera : Syrphidae) de l’üle de Lesbos (GrĂšce), dans la MĂ©diterranĂ©e Orientale

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    Descriptions are given of two new species of Merodon Meigen (Diptera: Syrphidae) from the island of Lesvos (Greece): Merodon papillus Vujić, Radenkovic & PĂ©rez-Bañón n. sp. from the ruficornis group species and Merodon sapphous Vujic, PĂ©rez-Bañón & Radenkovic n. sp. from the aureus group. In addition to classical morphological characters, partial sequences of the mitochondrial COI gene are generated for each taxon as DNA ‘barcodes’. Main characteristics of the species habitats are reported. The zoogeographical significance of these endemic taxa to the biodiversity of the island is discussed.European Commission Framework 6 Integrated project ALARM (Assessing LArge scale environmental Risks for biodiversity with tested Methods) (GOCE-CT-2003-506675) & Ministry of Science, Technology and Development of Republic Serbia (project number 143037)

    Phylogeographic patterns of Merodon hoverflies in the Eastern Mediterranean region: revealing connections and barriers

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    We investigated the phylogeographic patterns of Merodon species (Diptera, Syrphidae) in the Eastern Mediterranean. Ten species were sampled on five different islands and mainland sites as a minimum. All samples were screened for their mtDNA COI barcode haplotype diversity, and for some samples, we additionally generated genomic fingerprints. The recently established zoogeographic distribution categories classify these species as having (1) Balkan distribution; (2) Anatolian distribution; (3) continental areas and large islands distribution; and (4) with wide distribution. The ancestral haplotypes and their geographical localities were estimated with statistical parsimony (TCS). TCS networks identified as the ancestral haplotype samples that originated from localities situated within the distributional category of the species in question. Strong geographical haplotype structuring was detected for many Merodon species. We were particularly interested to test the relative importance of current (Aegean Sea) and past Mid-Aegean Trench) barriers to dispersal for Merodon flies in the Aegean. We employed phylogenetic ÎČ-diversity (PÎČ total) and its partition in replacement (PÎČ repl) and richness difference (PÎČ rich) to test the importance of each explanatory variable (interisland distance, MAT, and island area) in interisland differences using partial Mantel tests and hierarchical partitioning of variation. ÎČ-Analyses confirmed the importance of both current and past barriers to dispersal on the evolution of group. Current interisland distance was particularly important to explain the replacement of haplotypes, while the MAT was driving differences in richness of haplotypes, revealing the MAT as a strong past barrier whose effects are still visible today in the phylogenetic history of the clade in the Aegean. These results support the hypothesis of a highly restricted dispersal and gene flow among Merodon populations between islands since late Pleistocene. Additionally, patterns of phylogeographic structure deduced from haplotype connections and ISSR genome fingerprinting data revealed a few putative cases of human-mediated transfers of Merodon spp

    Farmers' attitudes and landscape change: evidence from the abandonment of terraced cultivations on Lesvos, Greece

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    Agricultural landscapes are the product of the interaction of the natural environment of an area and the practices of its farmers. In this paper, farmers' practices are examined in order to describe and understand processes of landscape change in terraced fields on the island of Lesvos, Greece. We examine the changes of the terraced fields of each farmer and the reasons for these changes, practices concerning the maintenance of terraces and how farmers view this landscape change. The concept of farming systems is used to link farmers' practices at the farm level with changes at the landscape level. Data come from research via questionnaires to farmers in order to record their practices, to explore changes in land use and the landscape elements and the reasons behind these changes, and finally to record their opinions on the landscape change that result. Findings indicate that although farm households in the case study areas depend on farming incomes by very different degrees, they employ similar cultivation and landscape management practices. At the same time, "hobby" farm households may be more prone to abandonment of fields and negligence of landscape elements (here terraces)

    A critical analysis of the potential for EU Common Agricultural Policy measures to support wild pollinators on farmland

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    1. Agricultural intensification and associated loss of high‐quality habitats are key drivers of insect pollinator declines. With the aim of decreasing the environmental impact of agriculture, the 2014 EU Common Agricultural Policy (CAP) defined a set of habitat and landscape features (Ecological Focus Areas: EFAs) farmers could select from as a requirement to receive basic farm payments. To inform the post‐2020 CAP, we performed a European‐scale evaluation to determine how different EFA options vary in their potential to support insect pollinators under standard and pollinator‐friendly management, as well as the extent of farmer uptake. 2. A structured Delphi elicitation process engaged 22 experts from 18 European countries to evaluate EFAs options. By considering life cycle requirements of key pollinating taxa (i.e. bumble bees, solitary bees and hoverflies), each option was evaluated for its potential to provide forage, bee nesting sites and hoverfly larval resources. 3. EFA options varied substantially in the resources they were perceived to provide and their effectiveness varied geographically and temporally. For example, field margins provide relatively good forage throughout the season in Southern and Eastern Europe but lacked early‐season forage in Northern and Western Europe. Under standard management, no single EFA option achieved high scores across resource categories and a scarcity of late season forage was perceived. 4. Experts identified substantial opportunities to improve habitat quality by adopting pollinator‐friendly management. Improving management alone was, however, unlikely to ensure that all pollinator resource requirements were met. Our analyses suggest that a combination of poor management, differences in the inherent pollinator habitat quality and uptake bias towards catch crops and nitrogen‐fixing crops severely limit the potential of EFAs to support pollinators in European agricultural landscapes. 5. Policy Implications. To conserve pollinators and help protect pollination services, our expert elicitation highlights the need to create a variety of interconnected, well‐managed habitats that complement each other in the resources they offer. To achieve this the Common Agricultural Policy post‐2020 should take a holistic view to implementation that integrates the different delivery vehicles aimed at protecting biodiversity (e.g. enhanced conditionality, eco‐schemes and agri‐environment and climate measures). To improve habitat quality we recommend an effective monitoring framework with target‐orientated indicators and to facilitate the spatial targeting of options collaboration between land managers should be incentivised

    In search of traces of the mandrake myth: the historical, and ethnobotanical roots of its vernacular names

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    Mandrake (Mandragora spp.) is one of the most famous medicinal plant in western cultures since Biblical times and throughout written history. In many cultures, mandrake is related to magic and witchcraft, which is said to have a psychosomatic effect (especially when mandrake contains narcotic compounds) in addition to the pharmacological influence, as occurs with other narcotic magical plants. Due to its unique properties and related myths, it is not surprising that this plant has many names in many languages. Methods: This paper presents an attempt to reconstruct the historical, ethnobotanical, and folkloristic roots of 292 vernacular names of Mandragora spp. in forty-one languages. We used the plant’s morphological data, philology, myths and legends, medicinal properties and uses, as well as historical evidence and folkloric data, to explain meaning, origin, migration, and history of the plant’s names. Results: The names were classified into the following main categories: Derivatives of mandragora (19 languages), alraun (7) and of yabroukh (5). The salient groups of the plant’s vernacular names are related to: Anthropomorphism (33 names in 13 languages); Similarity to other plants (28/9); Supernatural agents (28/9); Narcotic effects (21/8); Leaves, fruits, and seeds (21/8); Aphrodisiac properties (17/10); Use of a dog (15/9); Gallows (14/5); Black magic, sorcery, witchcraft (13/8), and Medicinal use (11/7). Conclusions: This frequency distribution of the mandrake’s vernacular names reflects its widespread reputation as related to the doctrine of signatures, beliefs in its supernatural, natural, and mythic powers, and to a lesser extent, its uses in magic and medicine. A spatiotemporal analysis of the mandrake’s names supports the old idea that the pulling ceremonies for this plant originated in the Near East and that various other myths related to this plant may have originated in different places and periods

    Temporal scale‐dependence of plant–pollinator networks

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    The study of mutualistic interaction networks has led to valuable insights into ecological and evolutionary processes. However, our understanding of network structure may depend upon the temporal scale at which we sample and analyze network data. To date, we lack a comprehensive assessment of the temporal scale-dependence of network structure across a wide range of temporal scales and geographic locations. If network structure is temporally scale-dependent, networks constructed over different temporal scales may provide very different perspectives on the structure and composition of species interactions. Furthermore, it remains unclear how various factors – including species richness, species turnover, link rewiring and sampling effort – act in concert to shape network structure across different temporal scales. To address these issues, we used a large database of temporally-resolved plant–pollinator networks to investigate how temporal aggregation from the scale of one day to multiple years influences network structure. In addition, we used structural equation modeling to explore the direct and indirect effects of temporal scale, species richness, species turnover, link rewiring and sampling effort on network structural properties. We find that plant–pollinator network structure is strongly temporally-scale dependent. This general pattern arises because the temporal scale determines the degree to which temporal dynamics (i.e. phenological turnover of species and links) are included in the network, in addition to how much sampling effort is put into constructing the network. Ultimately, the temporal scale-dependence of our plant–pollinator networks appears to be mostly driven by species richness, which increases with sampling effort, and species turnover, which increases with temporal extent. In other words, after accounting for variation in species richness, network structure is increasingly shaped by its underlying temporal dynamics. Our results suggest that considering multiple temporal scales may be necessary to fully appreciate the causes and consequences of interaction network structure.Fil: Schwarz, Benjamin. Albert Ludwigs University of Freiburg; AlemaniaFil: Vazquez, Diego P.. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Cara Donna, Paul J.. Chicago Botanic Garden; Estados UnidosFil: Knight, Tiffany M.. German Centre for Integrative Biodiversity Research; AlemaniaFil: Benadi, Gita. Albert Ludwigs University of Freiburg; AlemaniaFil: Dormann, Carsten F.. Albert Ludwigs University of Freiburg; AlemaniaFil: Gauzens, Benoit. German Centre for Integrative Biodiversity Research; AlemaniaFil: Motivans, Elena. German Centre for Integrative Biodiversity Research; AlemaniaFil: Resasco, Julian. University of Colorado; Estados UnidosFil: BlĂŒthgen, Nico. Universitat Technische Darmstadt; AlemaniaFil: Burkle, Laura A.. Montana State University; AlemaniaFil: Fang, Qiang. Henan University of Science and Technology; ChinaFil: Kaiser Bunbury, Christopher N.. University of Exeter; Reino UnidoFil: AlarcĂłn, Ruben. California State University; Estados UnidosFil: Bain, Justin A.. Chicago Botanic Garden; Estados UnidosFil: Chacoff, Natacha Paola. Universidad Nacional de TucumĂĄn. Instituto de EcologĂ­a Regional. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - TucumĂĄn. Instituto de EcologĂ­a Regional; ArgentinaFil: Huang, Shuang Quan. Central China Normal University; ChinaFil: LeBuhn, Gretchen. San Francisco State University; Estados UnidosFil: MacLeod, Molly. Rutgers University; Estados UnidosFil: Petanidou, Theodora. Univversity of the Aegean; Estados UnidosFil: Rasmussen, Claus. University Aarhus; DinamarcaFil: Simanonok, Michael P.. Montana State University; Estados UnidosFil: Thompson, Amibeth H.. German Centre for Integrative Biodiversity Research; AlemaniaFil: FrĂŒnd, Jochen. Albert Ludwigs University of Freiburg; Alemani

    Identifying bottlenecks in the life cycle of plants living on cliffs and rocky slopes: Lack of knowledge hinders conservation actions

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    Long term survival of plant populations relies on successful reproductive cycle to obtain generation turnover. Focusing on plant species of conservation concern, we brought together a group of plant conservationists from different countries to assess whether the already available information on plant reproductive biology and autecology is adequate for identifying which phases of single species life cycle might act as bottleneck. We compiled a list of 80 plant species of conservation concern living on European cliffs and rocky slopes, for which biological and autecological information was collected from scientific literature, technical reports, and expert knowledge. Results have shown that the available information on species reproductive biology and autecology is inadequate to identify bottlenecks in the life cycle of many species and to provide insights for the practical conservation of many more. Available knowledge is mainly referred to the flowering phase, less on seed production and much less on seedling establishment and on cloning. Meanwhile and noteworthy, flowering resulted to be the less critical phase for the fulfilment of the species life cycle. Overall, with this perspective article we aim to encourage a constructive debate among the scientific community members and policymakers to set up novel concerted strategies for the conservation of plant species of conservation concern. The challenge of the discussion is the implementation of the current approach with new biological and ecological information to be exclusively targeted at identifying the constraints that limit the generation turnover and furnishing specific indications for active management
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