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This work discusses the stratigraphy and facies analysis of the Ranzano Sandstone, in the northern Apennines (Italy), a confined low-efficiency turbidite system deposited in a series of small piggy-back basins, which show strong analogies with intraslope minibasins commonly observed in divergent margins. The detailed physical stratigraphy of these deposits, which are the counterpart of the Annot Sandstone of the classic "Trilogie Priabonienne" cropping out in the western Alps, shows a cross-current asymmetrical distribution of the facies related to basin morphology. In an E-W oriented transect, roughly perpendicular to the general paleocurrents directed towards SSW, coarse-grained amalgamated massive sandstones that onlap against the eastern basin margin, grade towards the west, over very short distances, into a stratigraphic succession dominated by coarse-grained sandstones reworked in megaripples. This westward lateral facies change is also associated with: a) progressive deviation of the megaripple paleocurrents towards the west, b) progressive eastward increase in the sandstone/mudstone ratio, impact flow structures and beds with mudstone clasts, and c) progressive westward decrease in bed thickness characterizing massive facies. This cross-current transition is interpreted as related to bipartite turbidity currents experiencing deceleration against a relatively steeper eastern margin, producing flow decoupling and consequent bypass of upper turbulent flows that can spread out towards the less steep western bounding slope. The lateral spreading of turbulent flows causes reworking of the coarse-grained massive facies, producing tractive structures that indicate westward flow divergence. The lack of medium, fine-grained sands and mud testifies that these grain sizes must have been transported by turbulent flows into another adjacent basin, allowing the described deposits to be interpreted as recording a "flow stripping" phase as found in the ponded intraslope basins of the Gulf of Mexico and other confined settings, such as wedge-top basins and inner foredeeps. [ABSTRACT FROM AUTHOR]

This study explores the factors affecting the biodiversity of diatoms, vegetation with focus on bryophytes, and invertebrates with focus on water mites, in a series of 16 spring-habitats. The springs are located primarily from the mountainous part of the Emilia-Romagna Region (Northern Apennines, Italy), and two pool-springs from agricultural and industrial lowland locations. Overall, data indicate that biological diversity (Shannon-Wiener, α-diversity) within individual springs was relatively low, e.g.: S diatoms  = 0-46, S water-mites  = 0-11. However, when examined at the regional scale, they hosted a very high total number of taxa (γ-diversity; S diatoms  = 285, S water-mites  = 40), including several new or putatively-new species, and many Red-List taxa. This pattern suggested there is high species turnover among springs, as well as high distinctiveness of individual spring systems. A key goal was to assess the hydrogeological and hydrochemical conditions associated with this high regional-pool species richness, and to provide a guide to future conservation strategies. There was a striking variety of geological conditions (geodiversity, captured mainly with lithotype and aquifer structure) across the study region, which led to wide variation in the hydrosphere, especially in conductivity and pH. Agriculture and industrial activities (anthroposphere) in the lowlands resulted in nutrient enrichment and other forms of pollution. Across all 16 spring-systems, several hydrogeological conditions most strongly influenced the presence or absence of particular biota and were determinants of species importance: spring-head morphology, hydroperiod, discharge, current velocity, and elemental concentration. These findings have important practical consequences for conservation strategies. Our data show that it is imperative to protect entire regional groups of springs, including representatives of the different ecomorphological spring types, lithologies, and degrees of human influence. These findings suggest that springs, when studied from an ecohydrogeological perspective, are excellent systems in which to further investigate and understand geo-biodiversity relationships., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)