34 research outputs found

    Detecting Intraspecific Character Displacement by Morphological Markers in Riverine-Dwelling Invertebrate Larvae: The Case Study of Head Shape Variability in Leuctra fusca (Plecoptera: Leuctridae)

    No full text
    Since morphological markers are recognized as useful tools to evaluate events of anthropic disturbances, we performed a preliminary study on head shape variability in the riverine-dwelling Leuctra fusca larvae as early alarm systems in running waters. Particularly, heads of 32 larvae were collected from two localities of River Aniene (central Italy) and photographed for digitizing landmarks and semilandmarks. The Cartesian x-y coordinates of all points were firstly converted to shape coordinates by Procrustes superimposition, and then analyzed for exploring the full potential of the application of geometric morphometric techniques. Where the principal component analysis revealed a clear pattern of variation between the 2 sampling sites, the Procrustes ANOVA highlighted this variation as highly associated with fluctuating asymmetry, the latter being traditionally connected with developmental accidents due to environmental conditions. No directional asymmetry was observed. Finally we didn’t find any pattern of allometric variation in the studied structure. Our study indicates that further studies ought to be employed to use geometric morphometrics as a valid tool for detecting and describing morphological variation as biomarkers in invertebrate organism such as stoneflies

    Remapping Hydroecoregion Boundaries: A Proposal for Improving the Base of the Running Water Monitoring Procedures

    No full text
    Inland waters are constituted by a lot of seriously threatened habitats. The increasing need to safeguard these ecosystems led European Union Member States to propose the Water Framework Directive which decided the creation of homogeneous areas characterized by very similar geology, topography and climate, known as hydroecoregions (HER) and firstly proposed by the French National Research Institute of Science and Technology for Environment and Agriculture (Cemagref). Watercourses reference conditions had to be defined within any HER in order to confront any sampling site. HERs are consistent with European scale maps but important local reinterpretations in order to define more precise boundaries and extensions for each hydroecoregion are required and this point constitutes the main goal of this manuscript.Latium is a climatically very homogeneous region and it’s roughly divided into three major portions confirming Cemagref’s proposal. Geological and topolographical maps were then used in order to achieve a more detailed characterization of this region in order to obtain a more defined map. All our results allow to better define similarities and differences both between streams and within the same stream allowing to entirely locate each water course within the same HER. It would be important to follow up this study by proposing a similar approach for the entire national territory based on an appropriate region knowledge

    Remapping Hydroecoregion Boundaries: A Proposal for Improving the Base of the Running Water Monitoring Procedures

    No full text
    Inland waters are constituted by a lot of seriously threatened habitats. The increasing need to safeguard these ecosystems led European Union Member States to propose the Water Framework Directive which decided the creation of homogeneous areas characterized by very similar geology, topography and climate, known as hydroecoregions (HER) and firstly proposed by the French National Research Institute of Science and Technology for Environment and Agriculture (Cemagref). Watercourses reference conditions had to be defined within any HER in order to confront any sampling site. HERs are consistent with European scale maps but important local reinterpretations in order to define more precise boundaries and extensions for each hydroecoregion are required and this point constitutes the main goal of this manuscript.Latium is a climatically very homogeneous region and it’s roughly divided into three major portions confirming Cemagref’s proposal. Geological and topolographical maps were then used in order to achieve a more detailed characterization of this region in order to obtain a more defined map. All our results allow to better define similarities and differences both between streams and within the same stream allowing to entirely locate each water course within the same HER. It would be important to follow up this study by proposing a similar approach for the entire national territory based on an appropriate region knowledge

    Detecting Intraspecific Character Displacement by Morphological Markers in Riverine-Dwelling Invertebrate Larvae: The Case Study of Head Shape Variability in Leuctra fusca (Plecoptera: Leuctridae)

    No full text
    Since morphological markers are recognized as useful tools to evaluate events of anthropic disturbances, we performed a preliminary study on head shape variability in the riverine-dwelling Leuctra fusca larvae as early alarm systems in running waters. Particularly, heads of 32 larvae were collected from two localities of River Aniene (central Italy) and photographed for digitizing landmarks and semilandmarks. The Cartesian x-y coordinates of all points were firstly converted to shape coordinates by Procrustes superimposition, and then analyzed for exploring the full potential of the application of geometric morphometric techniques. Where the principal component analysis revealed a clear pattern of variation between the 2 sampling sites, the Procrustes ANOVA highlighted this variation as highly associated with fluctuating asymmetry, the latter being traditionally connected with developmental accidents due to environmental conditions. No directional asymmetry was observed. Finally we didn’t find any pattern of allometric variation in the studied structure. Our study indicates that further studies ought to be employed to use geometric morphometrics as a valid tool for detecting and describing morphological variation as biomarkers in invertebrate organism such as stoneflies

    Sharing Ethnobotanical Knowledge in Traditional Villages: Evidence of Food and Nutraceutical â\u80\u9cCore Groupsâ\u80\u9d in Bali, Indonesia

    No full text
    The island of Bali has several aga (indigenous) villages that have survived despite the pressures of an intense tourist industry and agricultural changes. A rich ethnobotanical culture persists, but the meaning of differences in traditional ethnobotanical knowledge (TEK) remains under-explored. We analyzed information obtained from interviews of inhabitants from diverse villages on food and nutraceutical plants to identify plant patterns, i.e., relevant plant groups with species sharing a similar occurrence. Through cluster analysis, we identified 12 main groups of species and found that species were grouped based on traditional knowledge and the use each community made of plants on the whole, and not on growth forms nor on specific uses. The frequency distribution of species clusters showed a bimodal trend, with several groups present only in few villages, and a few groups present in almost all villages. The latter are defined as â\u80\u9ccore groups,â\u80\u9d and represent the shared TEK of each aga community. Other â\u80\u9csatellite species groupsâ\u80\u9d embodied in the local TEK were related to small isolated communities. Cultural erosion caused by modernization, with the consequent fragmentation of information, was judged to be one of the main causes of increasing TEK heterogeneity

    The freshwater grass shrimp Palaemonetes antennarius in the diet of fish in Lake Bracciano (Central Italy)

    No full text
    We evaluated the importance of the freshwater grass shrimp Palaemonetes antennarius as trophic source for the lacustrine fish of the Lake Bracciano (Central Italy) analyzing 6120 stomach contents of 10 species. Shrimp was recorded for all size classes of the investigated species with a variation in frequency and abundance depending on seasons. P. antennarius was occasionally preyed by cyprinids, and systematically small individuals of carnivorous fish. Our findings acquire more importance if we take the shrimps ecological niche into account, as it is potentially acting as detritivorous/generalist and predator of benthic invertebrates as well. This feeding behavior makes P. antennarius an important network ring, being a taxon that ought to receive the same attention recommended for other freshwater decapods as proposed for Austropotamobius pallipes and Potamon fluviatile
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