402 research outputs found

    Vertebrate-mediated seed rain and artificial perches contribute to overcome seed dispersal limitation in a Mediterranean old field

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    Natural regeneration of vegetation is a frequent outcome of land abandonment, although the rate and diversity of such regeneration may be severely restricted by seed dispersal limitation, among other factors. In spite of this, studies aiming to quantify seed rain and test methods to enhance it, such as artificial perches, are still underrepresented in the Mediterranean. In our study, we quantified seed rain density and richness and tested the effects of artificial perches on such rain over a distance gradient on seven Mediterranean island old fields. In each of the seven sites, we positioned three sampling stations, each consisting of 1 seed trap under an artificial perch and 1 as a control on the ground, distributed at 30, 60, and 90 m from natural vegetation remnant. All traps received seeds, suggesting no overall dispersal limitation. Of the 11 seed species found, 10 were fleshy-fruited and dispersed by vertebrates. Seed traps under perches received significantly higher seed rain of fleshy-fruited species dispersed by birds, while ground traps received significantly more seeds of the species also dispersed by mammals, especially Rubus ulmifolius. The distance from the seed source was nonsignificant in all cases. Our study demonstrates the key role of vertebrate-mediated seed dispersal services to overcome dispersal limitation in old fields, as well as the effective contribution of even small artificial perches in contrasting such limitation. The lack of differences over the distance gradient reveal that the upper spatial limit of dispersal limitation was not achieved

    Sambucus nigra L. (fam. Viburnaceae) in Sicily: Distribution, Ecology, Traditional Use and Therapeutic Properties

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    Sambucus nigra, the elderberry, has long been used for its medicinal properties in treating numerous diseases. Based on this traditional knowledge, its different pharmacological activities have been the focus of active research. All parts of the tree have long been used in traditional medicine, that is, the bark, the leaves, the flowers and the fruit. This study, carried out in Sicily (Italy), concerns the traditional uses of elder against human diseases. In order to trace the history of man's interaction with elder on the island, multidisciplinary research was carried out, aiming at (1) presenting a comprehensive overview of elderberry's applications and activities and (2) bridging traditional knowledge (uses and beliefs) with modern science, i.e., the most recent scientific findings in the biomedical and pharmacological fields. A rigorous literature review of scientific (and other local) reports on the elderberry tree and its application in food, health and household applications was undertaken. This article also provides a synthetic and updated picture of the ecology and distribution of S. nigra in Sicily. The elderberry is quite widespread in Sicily, yet its distribution is discontinuous. It prefers hedges, riparian woodlands, forest margins and clearings and is rather common along the watercourses flowing in the canyons of the Hyblaean Plateau, in the Madonie Mts. and in Enna province. Indeed, many old plants are often found near sacred places and rural houses, suggesting that in the past, it was extensively planted on purpose for its multiple uses. The complementary data obtained from multidisciplinary research confirm the usefulness of this approach in building a comprehensive and correct picture of the distribution of the most common woody species, for which the available knowledge is often fragmentary and imprecise

    Flogosi post-trapianto di cornea

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    Il Trapianto di Cornea, o Cheratoplastica, che prevede la sostituzione sub-totale della cornea mediante un innesto circolare di tessuto omologo (lembo), rappresenta la procedura d’elezione per il trattamento di diverse patologie corneali congenite o acquisite. Se ne discutono tutti i determinanti e le prospettive

    Ecologia e distribuzione di Chamaerops humilis L. (Arecaceae) nella Sicilia nord-orientale

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    I settori costieri e collinari della Sicilia nord-orientale e delle Eolie sono stati esplorati ai fini della raccolta di informazioni aggiornate sulla distribuzione dei popolamenti di palma nana e sulle caratteristiche ecologiche delle stazioni che li ospitano. I risultati delle indagini di campo sono stati integrati dalla verifica dei toponimi locali legati ai nomi dialettali della specie. Si con- ferma la totale assenza della palma nana lungo l’intero settore costiero dei Nebrodi. Dei nove popolamenti accertati, quattro si trovano alle Eolie, due sul versante ionico e tre sul versante tir- renico dei Peloritani; uno di questi ultimi, localizzato su Capo Calavà, risulta inedito. La conco- mitanza di diversi fattori di stress e l’impatto plurisecolare dell’uomo è probabilmente responsa- bile del carattere relittuale di gran parte dei popolamenti considerati, che danno vita a consorzi molto discontinui, e sono rappresentati da piccoli nuclei che formano aggruppamenti semplifi- cati sotto un profilo fisionomico e poveri in termini floristici, perlopiù confinati in contesti roc- ciosi costieri. Di contro, la recente espansione della palma nana registrata a Lipari sembra dipen- dere dalla cessazione delle attività agricole. Infine, i casi di naturalizzazione registrati a Milazzo, Tindari, Panarea, Scaletta Zanclea e Taormina derivano dal suo uso come pianta ornamentale e pongono in risalto l’urgente necessità di regolamentare la sua introduzione per evitare l’inquina- mento genetico dei nuclei autoctoni.The coastal and hilly sectors of NE Sicily and the Aeolian Archipelago have been explored, in order to obtain up-to-date information on the distribution of the populations of Chamaerops humilis and on their site conditions. In addition to the field surveys, any local toponym possibly related to the Sicilian vernacular names of the dwarf palm was checked and verified throughout the investigat- ed area. The total absence of the species along the coasts of Nebrodi Massif is confirmed. Of the 9 extant populations, 4 are located on the Aeolian Islands, 2 along the Ionian coast and 3 along the Tyrrhenian coast of Peloritani Mountains: among them, the one of Capo Calavà represents a new record. The co-occurrence of centuries-long human disturbance and several forms of envi- ronmental stresses could be the reason for the relict connotation of most of the considered popu- lations, which also are very discontinuous and consisting of small patches formed by a few indi- viduals, in simplified and species-poor assemblages, mostly found on sea-facing rocky cliffs. On the other hand, the recent spread of Chamaerops humilis in Lipari could be related to the aban- donment of agricultural practices. Finally, the naturalisation cases recorded in Milazzo, Tindari, Panarea, Scaletta Zanclea and Taormina, where the dwarf palm escaped from public and private gardens, point out the urgent need of regulating its introduction, in order to avoid the genetic pol- lution of the autochthonous populations

    The effects of post-pasture woody plant colonization on soil and aboveground litter carbon and nitrogen along a bioclimatic transect.

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    We investigated the effects of woody plant colonization of abandoned pastures on soil and litter organic carbon (C) stocks and nitrogen (N) content along a bioclimatic transect in a semi-arid environment (Sicily, Italy). Soil samples were taken in three successional stages (grazed pasture, shrubland, forest) within each of three bioclimates (supramediterranean - \u201csupra\u201d, mesomediterranean - \u201cmeso\u201d, thermomediterranean - \u201cthermo\u201d). Organic C and N in litter and soil (0-10 cm and 10-30 cm depth) were determined, as well as soil bulk density. Especially at 0-10 cm depth, changes in C and N contents along successional stages differed among bioclimates. Soil organic carbon (SOC) stock decreased from pasture to shrubland and increased from shrubland to forest in \u201csupra\u201d, increased from pasture to shrubland and then remained stable in \u201cthermo\u201d, and was stable in \u201cmeso\u201d. Soil C/N ratio decreased with succession in \u201csupra\u201d, showed no significant trend in \u201cmeso\u201d, and increased with succession in \u201cthermo\u201d. Litter C stock increased with succession in \u201cmeso\u201d, increased from pasture to shrubland and decreased from shrubland to forest in \u201cthermo\u201d, and increased from pasture to shrubland and then remained stable in \u201csupra\u201d. Litter C/N ratio increased in \u201cthermo\u201d and \u201csupra\u201d from pasture to shrubland and from shrubland to forest, but did not change significantly with succession in \u201cmeso\u201d. The different trends in SOC among bioclimates may be caused by changes in the importance of litter input, litter decay rate and mineralization. Successional changes in \u201cmeso\u201d and \u201csupra\u201d appeared to be most affected by litter quality, while those in \u201cthermo\u201d appeared to be strongly influenced by limited litter decay due to low soil moisture and high temperature

    A case study of the application of hand-held mobile laser scanning in the planning of an Italian forest (Alpe Di Catenaia, Tuscany)

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    Precision forestry is becoming a key sector for forest planning because it allows complex analyses of forest data to be carried out simply and economically. It contributes to the integration between technicians and operators in the sector by guaranteeing the transparency of the forest management operations (Corona et al., 2017). In the context of the progressive development of technology, we investigated the feasibility of using the hand-held mobile laser scanner (HMLS) system in different types of forest sites and comparison of the characteristics of individual trees (tree height, diameters at breast height) with traditional surveys, applied with the aim to validate the performance of the system for a future alternative methodology for forest planning thanks to the collaboration with the forestry company “Dimensione Ricerca Ecologia Ambiente Italia” (D.R.E.Am. Italia). GEOSLAM ZEB HORIZON ™ laser scanner is a hand-held mobile laser scanner containing SLAM technology that can be solved the problem of no GNSS signal or poor signal under the forest canopy making it more practical for forest investigations (Gollob et al., 2020). 15 forest sample plots are selected to reflect different stand conditions in Mediterranean forests taking into count the development stage and density of the sub-canopy vegetation, as well as the species composition in the forest stands. The aim of this study is to show the possible extrinsic circumstances that make the method fail by varying the ecological status of forest plots

    Emergenze vegetali dell'Isola di Lampedusa

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    Per la peculiarit\ue0 storica, geografica ed ambientale l\u2019Isola di Lampedusa, e vista l\u2019estrema frammentariet\ue0 delle formazioni preforestali, l\u2019esiguit\ue0 dei popolamenti (e degli individui) delle specie legnose assumono un valore scientifico e conservazionistico particolarmente elevato. Per queste ragioni \ue8 stato fatto un censimento eseguito con strumentazione GPS. Sull\u2019isola crescono diverse specie di rilevante interesse conservazionistico, numerose sono infatti le specie endemiche, esclusive, rare e/o a rischio di estinzione perch\ue9 legate a habitat molto vulnerabili e localizzati. A questa ragione d\u2019interesse generale per questi taxa si somma il fatto che buona parte delle specie arboree tipiche della vegetazione primaria dell\u2019isola, il pi\uf9 delle volte sopravvivono localmente con popolamenti costituiti da pochissimi (e talora singoli!) individui. Juniperus turbinata e Olea europaea var. sylvestris sono le due specie forestali di gran lunga pi\uf9 comuni tra quelle indagate . Meno positivo \ue8 il risultato dell\u2019analisi della rinnovazione, che ha permesso di individuare appena una trentina di giovani individui di ginepro e nessuno di olivastro. La presenza delle due specie sull\u2019isola risulta circoscritta esclusivamente ai valloni stretti ed incisi che sboccano sulla costa meridionale dell\u2019isola, disegnando un complesso sistema in cui si alternano profonde insenature e pendii rocciosi subpianeggianti. Per ambedue le specie si \ue8 registrata una netta prevalenza (ca. 80% dei ginepri e ca. 95% degli olivastri!) in corrispondenza delle esposizioni meridionali dell\u2019isola che, sebbene pi\uf9 soleggiate godono dell\u2019effetto benefico dei venti umidi provenienti da meridione

    Are we ready for genetic testing in metabolic dysfunction-associated steatotic liver disease?

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    Metabolic dysfunction-associated steatotic liver disease (MASLD), with its steadily increasing prevalence, represents now a major problem in public health. A proper referral could benefit from tools allowing more precise risk stratification. To this end, in recent decades, several genetic variants that may help predict and refine the risk of development and progression of MASLD have been investigated. In this review, we aim to discuss the role genetics in MASLD plays in everyday clinical practice. We performed a comprehensive literature search of PubMed for relevant publications. Available evidence highlights the emergence of genetic-based noninvasive algorithms for diagnosing fatty liver, metabolic dysfunction-associated steatohepatitis, fibrosis progression and occurrence of liver-related outcomes including hepatocellular carcinoma. Nevertheless, their accuracy is not optimal and application in everyday clinical practice remains challenging. Furthermore, susceptible genetic markers have recently become subjects of great scientific interest as therapeutic targets in precision medicine. In conclusion, decisional algorithms based on genetic testing in MASLD to facilitate the clinician decisions on management and treatment are under growing investigation and could benefit from artificial intelligence methodology
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