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Abstract: We present the Messinian evaporite suite (Mediterranean region) and the Solfatara hydrothermal system (Phlegraean Fields volcanic province, Italy), discuss their implications for understanding the origin of sulfates on Mars and show preliminary sets of VNIR laboratory and in situ reflectance spectra of rocks from these geologic systems. The choice was based on a number of evidence relative to Mars: (1) the chemistry of the Martian sulfates, suggesting fluid interactions with possibly alkali-basaltic rocks and/or regolith; (2) close range evidence of sulfates within sedimentary formations on Mars; (3) sulfate spectral signatures associated to large-scale layered patterns interpreted as thick depositional systems on Mars. The Messinian evaporites comprise three units: primary shallow-water sulfates (primary lower gypsum: PLG), shallow- to deep-water mixed sulfates and clastic terrigenous deposits (resedimented lower gypsum: RLG), and shallow-water associations of primary sulfates and clastic fluvio-deltaic deposits (upper evaporites: UE). The onset of the Messinian evaporites records the transition to negative hydrologic budget conditions associated with the Messinian Salinity Crisis, which affected the entire Mediterranean basin and lasted about 640kyr. The Solfatara is a still evolving hydrothermal system that provides epithermal deposits precipitated from the interaction of fluids and trachybasaltic to phonolitic rocks. Thermal waters include alkali-chloride, alkali-carbonate and alkali-sulfate endmembers. The wide spectrum of sedimentary gypsum facies within the Messinian formation includes some of the depositional environments hitherto identified on Mars and others not found on Mars. The PLG unit includes facies associations correlated over long distances, that could be a possible analog of the stratified rock units exposed from Arabia Terra at least as far as Valles Marineris. The facies cycles within the UE unit can be compared to the sequences of strata observed in craters such as Holden and Eberswalden. The UE unit records paleoenvironmental changes which are ultimately controlled by terrestrial climatic variations. They can be considered as a reliable climatic proxy and may be useful for the reconstruction of climatic events on Mars. The intermediate Messinian RLG unit has not, at present, a well-defined depositional counterpart on Mars, although there are some similarities with the northern lowlands and Vastitas Borealis Formation. The dramatic variation of hydrologic budget conditions at the onset of the Messinian evaporites may provide criteria for the interpretation of similar variations on Mars. The volcanic rocks at the Solfatara bear some similarities with the “alkaline magmatic province” observed at the Gusev crater on Mars, and the assemblages of hydrothermal phases resulting from the Solfatara''s parent rocks could be analogues for processes involving Gusev-type rocks. The Messinian sulfates have a prevalent Ca-sulfatic composition and wide textural variability. Preliminary laboratory reflectance spectra of rock samples in the VNIR region reveal the signature of sulfates and mixtures of several Fe-bearing phases. At the Solfatara, in situ reflectance measurements of epithermal minerals close to active fumaroles showed the presence of Fe-bearing sulfates, hematite, Al- and K-sulfates and abundant amorphous fraction. XRD analysis supported this interpretation. The range of depositional facies observed in the Messinian units and the variety of minerals detected in the Solfatara will be useful for the interpretation of close range data of Mars. The spectral characterization at various scales of the Messinian sedimentary facies and the Solfatara hydrothermal minerals will both help in the exploration of Mars from orbit and with close range inspection. [Copyright &y& Elsevier]

The grey partridge became extinct in the province of Siena (central Italy) in the late seventies, whereas the red-legged partridge had already disappeared by the beginning of the twentieth century. Some reintroduction attempts of both species carried out in the 1980s gave encouraging but not definitive results, and failed after an initial success. This was probably due to the low number of birds released, the small size of the re-introduction areas, their isolation, the farm-bred origin of the partridges, and hunting. In the province of Siena, for the first time in Italy, a large-scale reintroduction program of grey and red-legged partridges was experimented. The project started up in 1995 with seven reintroduction areas for grey and four for red-legged partridge, and was extended to 19 areas (22,562 ha) for grey and 7 (6858 ha) for red-legged partridge in 2002. Population viability analyses for both species showed that if reintroduced populations were isolated they would be extinct in a few years. Therefore, a metapopulation approach was adopted (contemporary releases in reintroduction areas close to each other). In each area, 100-1000 partridges per year were released for a minimum of 3 years, from different farms in order to achieve the maximum initial genetic diversity. Releases were effected in late summer (August-September) in acclimatization pens containing 10-20 aviaries. The reintroduced population showed marked variability of some demographic parameters, such as pair density and brood production rate; instead, average brood size was relatively constant across the study areas, but with annual variations. Reintroduction success was limited to a few areas only, mainly depending on the habitat characteristics of the areas, their surface area and isolation, and on the degree of care for the birds during the acclimatization period. [ABSTRACT FROM AUTHOR]