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We studied the relation between three different biotic groups (animal active dispersers, animal passive dispersers and plants) and spatial patterns and environmental conditions in two networks of Mediterranean temporary ponds. Plant and macrofaunal assemblages in Mediterranean temporary ponds seem to have different spatio-temporal patterns, being plants more dependent on spatial factors and macrofauna on temporal changes.

The temporal patterns of six biotic groups (amphibians, macroinvertebrates with active and passive dispersal mode, microcrustaceans, vascular plants and phytoplankton) and the responses of each biotic group to environmental variation (water, pond and landscape variables) were studied in a set of Sardinian temporary ponds.

It is about time the assessment of trophic state in wetlands is no longer estimated through the regressions and thresholds modelled for deep-stratified lakes where sediment nutrient recycling was purposely neglected. We are in badly need of a system trophic indicator to be used as a reference for biological indicators. The recent use of biological communities (macro-invertebrates, diatoms, etc) for the evaluation of the “ecological state” of a water body implicitly requires the assessment of its “trophic state”.

“Paulis” project, funded in 2012 by the Region of Sardinia - Regional Law 7 August 2007, n. 7: ‘Promotion of scientific research and technological innovation in Sardinia’, was aimed to capturing the interest on these neglected habitats through the implementation of scientific and educational products.

The aims of our research were: i) to implement a checklist of vascular plants, and ii) to create an interactive guide for the identification of plants growing in the Mediterranean temporary ponds of Sardinia.

The high interest in Mediterranean temporary wetlands, which are habitats of Community Interest (3120, 3130 and 3170) in the Habitat Directive 92/43/EEC, is mainly for their characteristic flora or fauna which includes several rare or endangered species. Although the attention on the ecology and biodiversity of these habitats is continuously increasing, the majority of the available studies are based on a qualitative approach or separate statistical analyses of physical, chemical and biodiversity data while little information is available on the relation between plants and environmental features.

Invertebrate and amphibian biodiversity of Mediterranean temporary ponds has been studied in the island of Sardinia (Italy). Thirty-six temporary ponds have been sampled between 2007 and 2014. All the ponds were small (less than 8 ha), shallow (less than 2 m depth) and presented low human impacts (the main disturbance was the presence of livestock).

Water stock in Mediterranean Temporary ponds results from the hydorological balance between direct or indirect rainwater supply (inflow) and losses in the atmosphere, overflow, infiltration (outflow). Losses into the atmosphere are due either to evapotranspiration, which includes evaporation from open water, soil and canopy dampened by the rain and plant transpiration. Our research was aimed to relate the hydrological balance evaluated at landscape scale with the presence and size of over 100 ponds using historical series of meteorological data and satellite images freely available online. The study area is located in Sardinia, on a 44 km2 basaltic plateau, 550 m a.s.l, named Giara di Gesturi.

Mediterranean temporary wetlands are considered among the most biologically and biogeographically interesting ecosystems in the Mediterranean region so much to be defined “a floristic jewel”. Although a check list of vascular flora associated to these habitats is available for Sardinia, the information on species distribution is fragmented. Moreover many species are under-recorded because they are inconspicuous, exhibit a very short life cycle and are absent during unfavorable years, giving the impression that they have disappeared, whereas in fact they are still present in the soil seed-bank.

A research was carried out in six Temporary Wetlands (TWs), located in north-western Sardinia (Italy), with the aim to categorize the basic factors driving and linking soil genesis and plant assemblages in Mediterranean basin.

The aims of this research were to: i) assess plant biodiversity in Sardinian Mediterranean temporary wetlands (TWs); ii) identify key environmental factors affecting it and possible interactions with other taxonomic groups, and iii) define conservation issues. Plant biodiversity was evaluated at different spatial scale. The application of a fine-scale zonation sampling approach allowed identifying different assemblages “within TW”, with different floristic, structural, and sintaxonomical features at each site in the same relative position. Three belts were recognized: central, intermediate and outer characterised by different water depth and flooding period. Comparisons at scale of the entire temporary TW pointed out differences due to substratum, elevation and size. At temporal scale differences between assemblages were significant only in the same environmental conditions (e.g. TWs located at the same site). While vegetation pattern was mainly driven by “within TW” effect, investigation on soil pattern pointed out that it is mainly due to “a site effect”. Significant positive relationships were found between plant and crustacean assemblages, not only in terms of community structure but also at composition level. Conservation relevance was related to the presence of habitats of Community interest and listed species. Intraspecific variability and conservation status were assessed to some species strongly dependent to this habitat type (e.g. Isoetes histrix).

The aims of this research were to contribute to the knowledge of the Mediterranean temporary wet habitats vegetation and to investigate the spatial distribution and the temporal successions of plant communities under different hydrological regimes in North Western Sardinia. The vegetation was sampled in temporary wet habitats located in large depressions (temporary ponds), in small depressions in patchwork with the vegetation dominated by Myrtus communis (waterlogged soils) and in rocky outcrops (rock pools). Three belts were recognized in temporary ponds: a central belt, an intermediate belt, and an outer belt. Overall 11 associations and subassociations were identified, within 4 syntaxonomic classes: Potametea, Isoeto-Nanojuncetea, Isoeto-Littorelletea and Phragmito-Magnocaricetea. Four new associations have been described: Isoeto tigulianae-Callitrichetum brutiae, Romuleo requienii-Isoetetum histricis, Apio crassipedis-Elatinetum macropodae, and Lythro hyssopifoliae-Crassuletum vaillantii. Moreover, within the Preslion cervinae alliance of the Isoeto-Nanojuncetea class, a new Tyrrhenian suballiance Apienion crassipedis, has been established, for which the typical association is the Apio crassipedis-Isoetetum tigulianae Biondi & Bagella 2005 corr. hoc loco. Aquatic vegetation was found in the central and intermediate belt of the temporary ponds and within the rock pools. Late winter–spring amphibious communities were present in almost all temporary wet habitats. Summer plant communities were found exclusively in the central belt of temporary ponds.

The research was undertaken with the aims to improve the knowledge of small scale distribution of plant communities in Mediterranean temporary habitats and to evaluate their diversity and conservation relevance in order to provide a sound basis for the prioritization of conservation efforts according to the Habitats Directive.

From a biological and biogeographic point of view, Mediterranean temporary wet habitats are recognised to be amongst the most interesting habitats in the Mediterranean bioclimatic region. They are considered to be habitats of Community Interest and are included in the “standing water group”. Due to an overlap in the plant species and syntaxa indicated as characteristic, the assignment of the plant communities to the habitats 3120, 3130 and 3170* is far from straightforward. We propose that the Isoetion communities be assigned to habitat 3170*, the Preslion cervinae, Cicendio-Solenopsion and Agrostion pourretii communities to habitat 3120, and the Cyperetalia fusci and Littorelletea uniflorae communities to habitat 3130.