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Pollen analysis from Lago Alimini Piccolo provides the first record of mid- and late-Holocene vegetation history of a coastal area in the easternmost region of southern Italy (Salento-Peninsula). Terrestrial pollen taxa document expansions and declines of the Mediterranean forest, in relation to human activity and climate changes. Between 5200 and 4350 cal. BP a dense evergreen oak forest dominated the landscape; then a distinct opening of the forest is recorded (4350-3900 cal. BP). A new forest expansion (3900-2100 cal. BP) is characterized by an increase of Olea and evergreen shrubs, indicating a development of mediterranean climate conditions and increasing human disturbance. The Roman occupation period (2100-1500 cal. BP) shows a significant opening of the forest, expansion of halophytes and modest values of Olea. After 1500 cal. BP human impact causes a further decrease of the natural woodland in favour of an extraordinary expansion of Olea. The vegetation development at Lago Alimini Piccolo, interpreted in the light of other pollen records, provides new insights into climate evolution and evergreen vegetation development in the central Mediterranean region: (1) a temporary mid-Holocene deforestation at 4000 cal. BP involving many Italian sites south of 43 degrees N was possibly caused by drought associated with an expansion or northward displacement of the North African high pressure zone; (2) the Bronze Age increase of Olea, coupled with a widespread increase of Mediterranean shrubs, suggests management of wild trees, while the beginning of intensive cultivation of olive trees is only found after the Roman time

Palynological, sedimentological and geochemical analyses performed on the Villarquemado paleolake sequence (987 m a.s.1, 40 degrees 30'N; 1 degrees 18'W) reveal the vegetation dynamics and climate variability in continental Iberia over the last 13,500 cal yr BP. The Lateglacial and early Holocene periods are characterized by arid conditions with a stable landscape dominated by pinewoods and steppe until ca. 7780 cal yr BP, despite sedimentological evidence for large paleohydrological fluctuations in the paleolake. The most humid phase occurred between ca. 7780 and 5000 cal yr BP and was characterized by the maximum spread of mesophytes (e.g., Betula, Coorlus, Quercus faginea type), the expansion of a mixed Mediterranean oak woodland with evergreen Quercus as dominant forest communities and more frequent higher lake level periods. The return of a dense pinewood synchronous with the depletion of mesophytes characterizes the mid-late Holocene transition (ca. 5000 cal yr BP) most likely as a consequence of an increasing aridity that coincides with the reappearance of a shallow, carbonate wetland environment. The paleohydrological and vegetation evolution shows similarities with other continental Mediterranean areas of Iberia and demonstrates a marked resilience of terrestrial vegetation and gradual responses to millennialscale climate fluctuations. Human impact is negligible until the lbero-Roman period (ca. 2500 cal yr BP) when a major deforestation occurred in the nearby pine forest. The last 1500 years are characterized by increasing landscape management, mainly associated with grazing practices shaping the current landscap

Geomorphologic, stratigraphic, faunistic, palynological and carbon isotope analyses were carried out in the area of the Tiber river mouth. The results depict a complex palaeoenvironmental evolution in the area of the Roman town of Ostia, ascertain the changes of the Tiber river delta over the last 6000 years and support a re-interpretation of some archaeologic issues. The wave-dominated Tiber delta evolved through three distinct phases. In the first step (5000-2700 yr BP) a delta cusp was built at the river mouth, which was located north of the present outlet. Subsequently (2700-1900 BP), an abrupt southward migration of the river mouth determined the abandonment of the previous cusp and the progradation of a new one. The third step, which is still in progress, is marked by the appearance of a complex cusp made up of two distributary channels. The transition from the first to the second evolution phase occurred in the seventh century BC and was contemporary to the foundation of Ostia, as suggested by historical accounts. However, the oldest archaeological evidence of the town of Ostia dates to the fourth century bc, when human activity is clearly recorded also by pollen data. We suggest that the first human settlement (seventh century bc) consisted of ephemeral military posts, with the aim of controlling the strategic river mouth and establishing the Ostia saltworks. Only after the fourth century bc the coastal environment was stable enough for the foundation and development of the town of Ostia

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The Mediterranean region and the Levant have returned some of the clearest evidence of a climatically dry period occurring around 4200 years ago. However, some regional evidence is controversial and contradictory, and issues remain regarding timing, progression, and regional articulation of this event. In this paper, we review the evidence from selected proxies (sea-surface temperature, precipitation, and temperature reconstructed from pollen, δ 18 O on speleothems, and δ 18 O on lacustrine carbonate) over the Mediterranean Basin to infer possible regional climate patterns during the interval between 4.3 and 3.8 ka. The values and limitations of these proxies are discussed, and their potential for furnishing information on seasonality is also ex-plored. Despite the chronological uncertainties, which are the main limitations for disentangling details of the climatic conditions, the data suggest that winter over the Mediterranean involved drier conditions, in addition to already dry summers. However, some exceptions to this prevail -where wetter conditions seem to have persisted -suggesting regional heterogeneity in climate patterns. Temperature data, even if sparse, also suggest a cooling anomaly, even if this is not uniform. The most common paradigm to interpret the precipitation regime in the Mediterranean -a North Atlantic Oscillation-like pattern -is not completely satisfactory to interpret the selected data.

A hundred pollen and plant macrofossil records from the Iberian Peninsula, Southern France, the Italian\ud Peninsula, Greece and the Aegean, and the southwestern Black Sea area formed the basis for a review of\ud the Quaternary distribution and extirpation of tree populations from Southern Europe. Following a\ud discussion of the caveats/challenges about using pollen data, the Quaternary history of tree taxa has been\ud reconstructed with attention to Taxodium/Glyptostrobus, Sciadopitys, Cathaya, Cedrus, Tsuga, Eucommia,\ud Engelhardia, Carya, Pterocarya, Parrotia, Liquidambar, and Zelkova. The timing of extinction, distributed\ud over the whole Quaternary, appears very diverse from one region to the other, in agreement with current\ud biodiversity in Southern Europe. The geographical patterns of persistence/disappearance of taxa show\ud unexpected trends and rule out a simple North to South and/or West to East trend in extirpations. In\ud particular, it is possible to detect disjunct populations (Engelhardia), long-term persistence of taxa in\ud restricted regions (Sciadopitys), distinct populations/species/genera in different geographical areas\ud (Taxodium type). Some taxa that are still widespread in Europe have undergone extirpation in Mediterranean\ud areas in the lateglacial period and Holocene (Buxus, Carpinus betulus, Picea); they provide an\ud indication of the modes of disappearance of tree populations that may be useful to evaluate correctly the\ud vulnerability of modern fragmented plant populations. The demographic histories of tree taxa obtained\ud by combined palaeobotanical and genetic studies is a most challenging field of research needed not only\ud to assess species/population differentiation, but also to reach a better understanding of extinction processes,\ud an essential task in the current global change scenario