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Contemporaneamente all'emersione di progetti di recupero del suo patrimonio storicoculturale, il paesaggio terrazzato della Media Valtellina di Tirano (Alpi centrali, Lombardia) ha negli ultimi anni guadagnato una posizione centrale nel discorso pubblico, sia a livello regionale che a quello, transfrontaliero e internazionale, della macroregione alpina. Tali progetti si focalizzano soprattutto sul restauro del patrimonio rurale, permettendone un nuovo impiego come substrato per la conduzione di attività agricole e turistiche, spesso integrate. Avvalendosi di interviste narrative con una serie di informatori chiave, sviluppate nell'ambito del progetto "Emblematici", l'articolo esplora, tramite un approccio qualitativo, la cultura contemporanea del terrazzamento in una regione fortemente contrassegnata dalla sua presenza. Questioni legate alla dimensione simbolica e culturale del terrazzamento si accompagnano a interrogativi riguardo al lavoro quotidiano, alle prospettive future di sviluppo dell'agricoltura locale e al ruolo dell'abbandono nella formazione del paesaggio culturale.

Aim Species-area relationships (SARs) are fundamental scaling laws in ecology although their shape is still disputed. At larger areas, power laws best represent SARs. Yet, it remains unclear whether SARs follow other shapes at finer spatial grains in continuous vegetation. We asked which function describes SARs best at small grains and explored how sampling methodology or the environment influence SAR shape. Location Palaearctic grasslands and other non-forested habitats. Taxa Vascular plants, bryophytes and lichens. Methods We used the GrassPlot database, containing standardized vegetation-plot data from vascular plants, bryophytes and lichens spanning a wide range of grassland types throughout the Palaearctic and including 2,057 nested-plot series with at least seven grain sizes ranging from 1 cm(2) to 1,024 m(2). Using nonlinear regression, we assessed the appropriateness of different SAR functions (power, power quadratic, power breakpoint, logarithmic, Michaelis-Menten). Based on AICc, we tested whether the ranking of functions differed among taxonomic groups, methodological settings, biomes or vegetation types. Results The power function was the most suitable function across the studied taxonomic groups. The superiority of this function increased from lichens to bryophytes to vascular plants to all three taxonomic groups together. The sampling method was highly influential as rooted presence sampling decreased the performance of the power function. By contrast, biome and vegetation type had practically no influence on the superiority of the power law. Main conclusions We conclude that SARs of sessile organisms at smaller spatial grains are best approximated by a power function. This coincides with several other comprehensive studies of SARs at different grain sizes and for different taxa, thus supporting the general appropriateness of the power function for modelling species diversity over a wide range of grain sizes. The poor performance of the Michaelis-Menten function demonstrates that richness within plant communities generally does not approach any saturation, thus calling into question the concept of minimal area. We thank all vegetation scientists who carefully collected multi‐ scale plant diversity data from Palaearctic Grasslands available in GrassPlot. The Eurasian Dry Grassland Group (EDGG) and the International Association for Vegetation Science (IAVS) sup‐ ported the EDGG Field Workshops, which generated a core part of the GrassPlot data. The Bavarian Research Alliance (grant BayIntAn_UBT_2017_58) and the Bayreuth Center of Ecology and Environmental Research (BayCEER) funded the initial GrassPlot workshop during which the database was established and the cur‐ rent paper was initiated. A.N. acknowledges support by the Center for International Scientific Studies and Collaboration (CISSC), Iran. C.M., I.B., I.G.‐M and J.A.C. were funded by the Basque Government (IT936‐16). D.V. carried out the research supported by a grant of the State Fund For Fundamental Research Ф83/53427. G.F. carried out the research in the frame of the MIUR initiative ‘Department of excellence' (Law 232/2016). I.D. was supported by the Polish National Science Centre (grant DEC‐2013/09/N/NZ8/03234). J.Do. was supported by the Czech Science Foundation (GA 17‐19376S). M.J. was supported by grant by Slovak Academy of Sciences (VEGA 02/0095/19). W.U. ac‐ knowledges support from the Polish National Science Centre (grant 2017/27/B/NZ8/00316).

During the last interglacial (LIG) period, global mean sea level (GMSL) was higher than at present, likely driven by greater high-latitude insolation. Past sea-level estimates require elevation measurements and age determination of marine sediments that formed at or near sea level, and those elevations must be corrected for glacial isostatic adjustment (GIA). However, this GIA correction is subject to uncertainties in the GIA model inputs, namely, Earth’s rheology and past ice history, which reduces precision and accuracy in estimates of past GMSL. To better constrain the GIA process, we compare our data and existing LIG sea-level data across the Bahamian archipelago with a suite of 576 GIA model predictions. We calculated weights for each GIA model based on how well the model fits spatial trends in the regional sea-level data and then used the weighted GIA corrections to revise estimates of GMSL during the LIG. During the LIG, we find a 95% probability that global sea level peaked at least 1.2 m higher than today, and it is very unlikely (5% probability) to have exceeded 5.3 m. Estimates increase by up to 30% (decrease by up to 20%) for portions of melt that originate from the Greenland ice sheet (West Antarctic ice sheet). Altogether, this work suggests that LIG GMSL may be lower than previously assumed.