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ABSTRACT Small-scale landscape elements such as freshwater ponds and pools remain poorly characterized and vulnerable to destruction, despite their significant contribution to regional aquatic biodiversity., Ephemeral wetland swards supporting Isoetes histrix, which are considered priority interest habitats by the European Habitats Directive on the conservation of wild fauna and flora (codex 3170* - Mediterranean temporary ponds), typify concave pond shorelines (Habitat A) and very shallow flat temporary ponds (Habitat B)., It is hypothesized that although this sward type is highly specialized for growth in waterlogged soils, it is highly sensitive to changes in composition and seasonal dynamics related to varied environmental conditions. The present study was aimed at comparing plant assemblages, and successional processes and dynamics during the growing season between different habitat types; and identifying the key factors influencing spatial variability., Vegetation was sampled three times during the growing season in the two habitat types (i.e A and B). At each site a range of environmental variables was also recorded., PERMANOVA analysis indicated that plant assemblages differed between the two habitat types throughout the growing season. The different hydroperiod length was the main factor responsible for the specificity of the two habitats, revealed by CCA. However, the pattern of successional processes and seasonal dynamics was similar between the two habitats., The results confirmed the hypothesis, and strengthened the understanding of the relevance of hydroperiod length to plant assemblages in ephemeral ponds., The two habitats exhibit unique characteristics, and represent different aspects of priority habitat 3170*; therefore, to ensure that the highest level of biodiversity is maintained, measures must be taken to protect both sward habitats., Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aims of this paper were (i) to define how contrasting land uses affected plant biodiversity in Mediterranean agro-silvo-pastoral-systems across a gradient of disturbance regimes: cork oak forests, secondary grasslands, hay crops, grass covered vineyards, tilled vineyards; (ii) to determine whether these patterns mirrored those of below-ground microorganisms and whether the components of γ-diversity followed a similar model. The disturbance regimes affected plant assemblage composition. Species richness decreased with increasing land use intensity, the Shannon index showed the highest values in grasslands and hay crops. Plant assemblage composition patterns mirrored those of Basidiomycota and Ascomycota. Richness in Basidiomycota, denitrifying bacteria and microbial biomass showed the same trend as that observed for vascular plant richness. The Shannon index pattern of below-ground microorganisms was different from that of plants. The plant γ-diversity component model weakly mirrored those of Ascomycota. Patchy diversity patterns suggest that the maintenance of contrasting land uses associated with different productions typical of agro-silvo-pastoral-systems can guarantee the conservation of biodiversity., (Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.)