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Spinescence refers to the presence of sharp appendages of various origins with ecological, evolutionary or biogeographic significance. This research was conducted to explore patterns and adaptive processes of thorns, spines and prickles in the Italian flora. We compiled an inventory of 401 spiny plants taking into account the following attributes: type of spinescence, family, biological form, chorotype, bioclimate and habitat. Then, we evaluated the incidence of plants with each attribute, the co-occurrence of various types of spinescence, the associations among spinescence types and biological forms and families, the structure of data across spinescence types, thermotypes and habitats. The spatial distributions and the adaptive processes of plants with various types of spinescence revealed that these patterns are driven by evolutionary, biogeographic and ecological factors, thus supporting the hypothesis that interactive processes of selective pressures and phylogenetic constraints have influenced the evolution of spinescences. [ABSTRACT FROM AUTHOR]

The article aims to examine the main water chemistry parameters (i.e. conductivity, pH, dissolved O2) and the ecological responses of 20 guide species in Mediterranean Temporary Ponds (MTPs). A complete data-set of 37 MTPs located in two different regions of Italy, Sardinia and Apulia, was compiled and the data were examined by means of Principal Component Analysis (PCA). The pattern of MTPs into the water chemistry space showed a clear separation between the two geographical regions. A "daisy diagram" obtained by overlapping five typologies of MTPs, obtained by the fuzzy cluster analysis and the PCA, revealed a good agreement between the sequence of groups and the water chemistry gradient. Groups of species sharing similar responses to the same chemical features were finally identified. These groups could be effective to acquire detailed information on the characteristics of MTPs and to improve their classification into different typologies. The guide species respond selectively to the wide variability range of conductivity, pH and dissolved oxygen. Despite the small size and the short hydroperiod water parameters in MTPs presented specific patterns to which the guide species are able to give specific responses. [ABSTRACT FROM AUTHOR]

Mediterranean agro-silvo-pastoral systems play a key role in view of the positive contribution that they could offer to a sustainable development of European agriculture. The knowledge of the vegetation dynamics and of the processes and land uses favoring different vegetation types related to the same actual potential natural vegetation (PNV) could represent a sound reference framework for monitoring and managing plant biodiversity in these systems. The aim of the research was to evaluate plant diversity along a gradient of use intensity comparing the actual vegetation versus the PNV. The results of our research showed that in the studied Mediterranean agro-silvo-pastoral system, included in the same environmental unit, human activities enhanced plant biodiversity. Moreover, the case study presented here confirmed the effectiveness of those landscape approaches comparing actual vegetation versus the PNV for plant biodiversity monitoring and reinforced previous studies showing the effect of human activities on plant community diversity at the environmental unit scale in different biogeographical contexts. [ABSTRACT FROM AUTHOR]

Temporary ponds (TPs) are shallow water bodies characterized by alternating phases of drought and flooding. They exhibit a small-scale zonation with a central belt (CB), an intermediate belt, and an outer belt (OB). Starting from the hypothesis that plant assemblage composition is affected by the position within TPs, our aims were to define the small-scale patterns of plant functional types, soil evolution, and soil physicochemical properties and to analyze their relationships and how they were affected by pond characteristics (i.e., elevation, substratum, total size, belt size, maximum water depth, and hydroperiod). Our results pointed out that patterns of plant functional types and soil evolution followed the position within the pond, soil physicochemical properties were weakly affected, and there was a relationship between plant functional types, soil small-scale patterns, and pond characteristics. Principal component analysis showed a positive correlation of Alfisols with CB, aquatic and amphibious species, maximum water depth, and hydroperiod, and of Entisols with OB and terrestrial species. A combined microtopography–hydrology effect was the primary factor controlling soil evolution and plant functional type patterns. As a consequence, modification in topographic shape and/or hydrologic parameters could alter TP environments. The results provide information for management strategies as an answer to the concerns surrounding continued worldwide TP decline. [ABSTRACT FROM AUTHOR]

A new microspecies of the Portulaca olearacea aggregate was identified in the course of a seed coat morphology analysis of 385 specimens from 55 sites located in Sardinia. This new taxon is here described under the name Portulaca sardoa. Apart from seed coat ornamentation, the new species differs from the others in chromosome number (2n = 48). Furthermore, a simplified key for the identification of the microspecies is provided. [ABSTRACT FROM AUTHOR]

This research was undertaken with the aim of improving our knowledge of the floristic composition and spatial-temporal dynamics of plant communities in Mediterranean temporary wet habitats, and to evaluate the diversity and conservation relevance of their plant assemblages. Three different types of temporary wet habitats were monitored throughout the growing season: large temporary ponds (lTPs), small temporary ponds (sTPs), and rock pools (RPs). lTPs presented a small-scale zonation arranged in an inner, an intermediate, and a peripheral belt. A total of 98 species were recorded, of which 40 were classified as temporary wet habitat (TWH) specialists and 24 as rare. Eight different groups of plant assemblages were identified presenting space-time dynamics related to water-depth variations and flooding period. In terms of diversity, the most relevant assemblages were located in the outer belt of the lTPs and in the sTPs. The mosaic of different assemblages and their time-variability determined the presence of several types of habitats of community interest according to the Habitat Directive. This wide heterogeneity should be taken into account to ensure that all types of TWHs are considered in conservation programmes. [ABSTRACT FROM AUTHOR]