1,721,050 research outputs found
Terricolous lichen communities in Thero-Airion dry grasslands of the Po Plain (Northern Italy): syntaxonomy, ecology and conservation value
No full textTerricolous lichen vegetation has been partially studied in Italy so far, particularly in the Po Plain. Here, pioneer acidic Thero-Airion dry grasslands host rich terricolous lichen communities which often include lichen species of conservation concern. Overall, 288 phytosociological releves were carried out with the Braun-Blanquet method using standard plots of 30 cm x 30 cm in lichen-rich stands within Thero-Airion dry grasslands located in 16 localities of the western Po Plain, an area with continental climate. Releves were manually sorted and species composition was analyzed through Principal Component Analysis (PCA) and non-parametric MANOVA. Biological, ecological, chorological and rarity spectra were computed and analyzed with Kruskal-Wallis tests to assess differences among the communities. Nine lichen communities were recognized. One community dominated by Cladonia pulvinata referred to the Pycnothelio-Cladonietum cervicornis. Three communities referred to the Cladonietum foliaceae are dominated respectively by C. foliacea, C. furcata and C. rangiformis. Three communities referred to the Cladonietum rei are dominated respectively by C. rei, C. polycarpoides and C. coccifera. Two communities dominated respectively by C. peziziformis and C. cariosa are referred to an undescribed association, temporarily attributed to the Cladonion rei. All communities significantly differ in the mean ecological indicator values - soil pH, light, aridity, eutrophication, poleotolerance. The communities Pycnothelio-Cladonietum cervicornis, Cladonietum foliaceae (C. foliacea facies) and the C. peziziformis-C. cariosa community are pioneer communities. The Cladonietum rei (C. rei facies) and the Cladonietum foliaceae (C. rangiformis facies) are the more mature communities, respectively in disturbed and undisturbed sites. This study shows that terricolous lichen communities represent an important component of biodiversity in Thero-Airion dry grasslands, due to their diversification in different syntaxa and, in some cases, to their role as microhabitats for lichen species of conservation concern. Thus, our study contributes to the knowledge on Thero-Airion dry grasslands, which is a key component in the choice of management and conservation strategies
Terricolous lichen communities of Corynephorus canescens grasslands of Northern Italy
No full textIn Italy most of the habitats hosting terricolous lichens are found in the Alps and along the coasts, but some lichen-rich plant communities are also present in the Po Plain. We report a study of terrico-lous lichen communities found in dry grasslands attributed to Spergulo vernalis-Corynephoretum canescentis in the western Po Plain (Northern Italy), in accordance with the Braun-Blanquet approach. Relevés (138) were carried out in several developmental stages of the Corynephorus grassland. They were sorted manually and analyzed using ANOSIM, non-parametric MANOVA and PCA. Indicator species of the groups were found by means of INDVAL and SIMPER analyses and literature. Seven lichen vegetation types were distinguished. These were attributable to 4 described associations: Stere-ocauletum condensati, Cladonietum foliaceae (in which we found 3 subassociations: typicum, cladonietosum furcatae and cladonietosum subrangiformis), Cladonietum mitis and Cladonietum rei, and to one impoverished community (Cetraria aculeata community). Ordination of floristic variables showed several overlaps between communities, underlining the depleted floristic conditions found in the study area, where several species occur in many communities and other species are very rare, and thus play a minor role in the differentiation of the lichen vegetation types. Overlaps are also referable to intermediate conditions between one community and another, reflecting dynamic relationships, with Stereocauletum condensati, Cetraria aculeata community and Cladonietum foliaceae typicum having the most distinct pioneer character and Cladonietum mitis being the most evolved. Ordination of eco-logical variables based on the indices of substrate pH, light and humidity requirements and tolerance to eutrophication showed several overlaps between the communities, found to be from acidophytic to subneutrophytic, from rather to very photophytic, from mesophytic to rather xerophytic and from ani-trophytic to slightly nitrophytic. Rarity in Italy and conservation needs are discussed in detail, also in comparison with the situation of the same communities in central European Corynephorus grasslands. These grasslands and their typical lichen communities are rare in Italy and, though somewhat depleted, they are the habitat of several threatened lichen species at the southern margin of their distribution range. Therefore management plans should always consider both the cryptogamic and the vascular plant communities
Assessing the conservation value of forests: The redefinition of the Forest Status Quality indicator in a multiscale approach and its application in northern Italy (Lombardy)
Full text linkELEMENTI DI CRITICITA’ NELLA CONSERVAZIONE DEI SALICETI A SALIX ALBA L. IN PIANURA PADANA
No full textContribution to the knowledge of lichen flora of inland sand dunes in the western Po Plain (N Italy)
No full textThis paper describes the lichen flora surveyed in inland sand dunes, called dossi, in the western Po Plain (Lombardy region, Italy). Here, lichens were marginally known in comparison with the epigaeous component, but they were never studied before in relation to the epiphytic, epixylic and epilithic components. The floristic list includes 50 species; ecological and chorological analyses were carried out. Thirteen lichen species observed on various substrata were not reported in the lichen list of the Ticino Natural Park, which distances only few kilometres from our study area. Nine species are new for the Po phytoclimatic region and one species, Cladonia portentosa, is new for Lombardy. Particularly interesting are some species related to the Corynephorus grasslands, such as Cladonia sp. pl. and Stereocauloncondensatum, and three species usually absent, at our latitudes, beneath the montane belt: Cladonia digitata, Hypocenomyce scalaris and Parmeliopsis ambigua. These data confirm the importance of inland sand dunes for lichen diversity of the Po Plain. Some preliminary remarks concerning the management of the habitats hosting lichens are given, with particular emphasis to their conservation. Suggested actions include the possibility to keep woody coarse debris, to favour epixylic species, and mechanical disturbance, dispersal of lichen fragments and sheep grazing, to favour epigaeous species
Terricolous lichen communities in Thero-Airion dry grasslands of the Po Plain (Northern Italy): syntaxonomy, ecology and conservation value|Erdflechtengesellschaften in Thero-Airion Trockenrasen der Po-Ebene (Norditalien): Syntaxonomie, Ökologie und Erhaltungswert
No full textUsing a Large Database to Test the Reliability of Indicator Values for the Italian Vascular Flora. An Application Regarding the Cilento National Park Phytosociological Dataset.
No full textAbstract book, ASSINI S., BRACCO F., NOLA P. (Eds), 46° Congresso SISV “Countdown 2010 Save Biodiversity. Il contributo della scienza della vegetazione”. Pavia 17-19 Febbraio 2010
Habitat loss, extinction debt and climate change threaten terricolous lichens in lowland open dry habitats
Full text linkHabitat loss is the main driver of biodiversity decline worldwide. An immediate consequence can be extinction debt, i.e. time-delayed extinction of species following habitat loss. We tested extinction debt in terricolous lichen communities in 45 patches of lowland open dry habitats in the western Po Plain (northern Italy) considering richness of four species groups: total, red-listed, rare, and common species. The distance from the currently nearest patch and the annual precipitation correlated – negatively and positively, respectively – with all the groups. Total, red-listed, and rare species were positively related to the oldest available patch extent (1954). Common species were positively related to the current (2020) patch extent. Total and red-listed species were negatively related to the extent difference (1954–2020). Results reveal an extinction debt which has not yet been completely paid and that could be exacerbated by climate change. To counteract this trend, management should conserve habitat patches with the highest species richness, improve connectivity between habitat patches, and provide suitable microrefugia for species with different ecological requirements
Banche dati e reti di monitoraggio della flora e della vegetazione: esperienze italiane e transfrontaliere
No full textEsprienze degli ultimi anni nella costruzione di banche dati e reti di monitoraggio transfrontaliere come frutto di numerosi progetti europei transfrontalieri nell'Italia settentrional
Network analysis of phenological units to detect important species in plant-pollinator communities: can it inform conservation strategies?
Full text linkConservation of species is often focused either only on those that are endangered, or on maximising the number recorded on species lists. However, species share space and time with others, thus interacting and building frameworks of relationships that can be unravelled by community-level network analysis. It is these relationships that ultimately drive ecosystem function via the transfer of energy and nutrients. However interactions are rarely considered in conservation planning. Network analysis can be used to detect key species ("hubs") that play an important role
in cohesiveness of networks. We applied this approach to plant-pollinator communities on two montane Northern Apennine grasslands, paying special attention to the modules and the identity of hubs. We performed season-wide sampling and then focused the network analyses on time units consistent with plant phenology. After testing for significance of modules, only some modules were found to be significantly segregated from others. Thus, networks were organized around a structured core of modules with a set of companion species that were not organized into compartments. Using a network approach we obtained a list of important plant and pollinator species, including three Network Hubs of utmost importance, and other hubs of particular biogeographical interest. By having a lot of links and high partner diversity, hubs should convey stability to networks. Due to their role in the networks, taking into account such key species when considering the management of sites could help to preserve the greatest number of interactions and thus support many other species
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