Oronzo Simone

The palaeoenvironmental study of the Alimini Piccolo lake enables a reconstruction of Holocene sea-level changes in southeast Italy

Based on multiproxy investigations of a 250 cm long sediment core (ALI1), a reconstruction of palaeoenvironmental dynamics for the Alimini Piccolo lake (south Adriatic coast of Apulia, Italy), is proposed. Our results indicate that shortly before 5500 cal. yr BP a marsh environment established. From 5400 cal. BP the marsh progressively became a lagoon and did not change until 3320 cal. BP, when Alimini Piccolo evolved into a shallow, sheltered, freshwater basin. Around 1400 cal. yr BP the basin became again a lagoon. Changes of the deposition environments and the chronological framework defined in the ALI1 sequence allowed speculation about local relative sea-level motions through the mid—late Holocene. Using proxy-data (molluscs, foraminifers, ostracods and plant macro-remains) as environment and bathymetry indicators, we reconstruct the elevation of the basin bottom (above or below sea level) through time. Plant macro-fossils have proved to be an especially reliable source of data for sea-level reconstruction. The resulting relative sea-level curve is characterised by a slow rise between 5500 and 3900 cal. yr BP, a drop culminating around 2500 cal. yr BP and a new, steeper rise continued to the present position. Our model differs from other curves (tectonically and isostatically corrected) proposed for a number of Mediterranean coastal sites where Holocene sea-level changes have been described with a continuously rising curve, steep before 7000—6000 yr BP, more gradual between 6000 yr BP and the present. On the other hand, our reconstruction seems to agree with evidence on sea-level position during the Roman age, found in several Apulian sites (Salento coastland) by means of geomorphological and archaeological investigations.

Climate changes and human–environment interactions in the Apulia region of southeastern Italy during the Neolithic period

The objective of our research was to define the main human–environment interactions during the Neolithic period (6500–3700 bc) in the Apulia region of southeastern Italy based on available published and unpublished data. Knowledge of these interactions is crucial to understanding the cultural and social dynamics of the period, particularly concerning the earliest farmers. Using a multidisciplinary approach, paleoenvironmental and paleoclimatological data at the regional and Mediterranean scales were compared with the results of analyses performed on natural deposits and deposits in Neolithic settlements. The following data sets were used: (1) 121 14C dates for settlements, from which probability curves (%) of the Apulian Archaeological Occupation (AAO) were developed; (2) offshore data obtained from analyses performed on two offshore sediment cores drilled in the Adriatic Sea; (3) offsite data from studies conducted in two natural coastal contexts; and (4) onsite archaeobotanical data from 35 settlements. This study allowed us to tentatively define the main climatic features between 6200 and 3700 bc. We identified two dry phases (one between 5000 and 4600 bc and a second that peaked c. 4000 bc) and two wet intervals (one between 6200 and 5500 bc and a second that peaked around 4400 bc). Climate changes appear to have been relatively gradual. The use of archaeobotanical data allowed us to determine a direct link between paleoclimatic and archaeological sequences. These data highlight the variations in agricultural strategies (species used and harvest times) as humans responded to changes in the rainfall regime.

Holocene Evolution of the Salpi Lagoon (Puglia, Italy)

ABSTRACT This paper attempts to reconstruct the evolution of the Salpi lagoon during the Holocene. The authors examined archaeological evidence and historical documents supplemented by field data. The research highlights the role of climatic variations and human interference in evolution of the lagoon. The data collected show that: At the beginning of the Holocene the sea level rise caused the development of a sandy barrier between Gargano Headland and Murge. This barrier enclosed a wide coastal lagoon, called “Laguna di Salpi”. Favourable environmental conditions permitted human occupation on the inner side of the lagoon during the early Neolithic by populations coming from the eastern coasts of the Adriatic Sea. At the end of the Neolithic the lagoon evolved into a sabkha and the whole area was abandoned until end of the 3rd millennium B.C. Between the III and I millennium B.C. the lagoon, communicating by several entrances with the sea, was deep enough for navigation. Between the II and I century B.C. the Tavoliere coastal area was affected by malaria and the lagoon settlements were abandoned. During the Middle Ages the Tavoliere coastal plain was almost depopulated, whereas the area around the lagoon was densely inhabited. Despite many attempts at reclamation during the Modern Age the whole Tavoliere was a malarial area. The lagoon then turned into a large coastal swamp which survived up to the 1930s when, after the “Serpieri - Iandolo” law, radical reclamation activities began. Two areas of the ancient Holocene lagoon still survive: the first is a swamp called Palude Frattarolo, the second is an area dedicated to salt production, called Saline di Margherita di Savoia.

New data on the Pleistocene of Trani (Adriatic Coast, Southern Italy)

Along the Apulian Adriatic coast, in a cliff south of Trani, a succession of three units (superimposed on one another) of marine and/or paralic environments has been recognised. The lowest unit I is characterised by calcareous/siliciclastic sands ( css ), micritic limestones ( ml ), stromatolitic and characean boundstones ( scb ), characean calcarenites ( cc ). The sedimentary environment merges from shallow marine, with low energy and temporary episodes of subaerial exposure, to lagoonal with a few exchanges with the sea. The lagoonal stromatolites ( scb subunit) grew during a long period of relative stability of a high sea level in tropical climate. The unit I is truncated at the top by an erosion surface on which the unit II overlies; this consists of a basal pebble lag ( bpl ), siliciclastic sands ( ss ), calcareous sands ( cs ), characean boundstones ( cb ), brown paleosol ( bp ). The sedimentary environment varies from beach to lagoon with salinity variations. Although there are indications of seismic events within the subunits cs , unit II deposition took place in a context of relative stability. The unit II is referable to a sea level highstand. Unit III, trangressive on the preceding, consists of white calcareous sands ( wcs ), calcareous sands and calcarenites ( csc ), phytoclastic calcirudite and phytohermal travertine ( pcpt ), mixed deposits ( csl, m, k, c ), sands ( s ) and red/brown paleosols ( rbp ). The sedimentation of this unit was affected by synsedimentary tectonic, attested by seismites found at several heights. Also the unit III is referable to a sea level highstand. The scientific literature has so far generally attributed to the Tyrrhenian (auct.) the deposits of Trani cliff. As part of this work some datings were performed on 10 samples, using the amino acid racemization method (AAR) applied to ostracod carapaces. Four of these samples have been rejected because they have shown in laboratory recent contamination. The numerical ages indicate that the deposits of the Trani cliff are older than MIS 5. The upper part of the unit I has been dated to 355±85 ka BP, thus allowing to assign the lowest stromatolitic subunit ( scb ) at the MIS 11 peak and the top of the unit I at the MIS 11-MIS 10 interval. The base of the unit II has been dated to 333±118 ka BP, thus attributing the erosion surface that bounds the units I and II to the MIS 10 lowstand and the lower part of the unit II to MIS 9.3. The upper part of the unit II has been dated to 234±35 ka BP, while three other numerical ages come from unit III: 303±35, 267±51, 247±61 ka BP. At present, the numerical ages cannot distinguish the sedimentation ages of units II and III, which are both related to the MIS 9.3-MIS 7.1 time range. However, the position of the units, superimposed one another, and their respective age, allows us to recognise a subsidence phase between MIS 11 and MIS 7, followed by an uplift phase between the MIS 7 and the present day, which led the deposits in their current position. This tectonic pattern is not in full agreement with what is described in the literature for the Apulian foreland.