Holocene environmental change through natural processes and human influence in Salento, South-East Italy : an integrated geomorphological and palynological investigation
South-east Italy is a region of distinct archaeological importance in which environmental factors have clearly played a major role in settlement site selection and economic development throughout the Holocene. Little is known, however, of how the environment has changed during this period. This research focuses on the Adriatic coastal margin of Salento between San Cataldo and Otranto, an important area of prehistoric and historic settlement. The research principally determines how and at what rate the environment of the study-area has changed during the Holocene as a result of the interaction between natural processes and human influence. For the first time, detailed scientific analysis is provided on Holocene environmental change in south-east Italy. Specifically, the impact of natural processes and human influence on vegetation patterns are investigated, together with the impact of Holocene relative sea-level rise on this low-lying, semi-arid coastal zone. The research aims are tackled by geomorphological and palynological investigations of the sedimentary record within the study-area in order to derive evidence for past environmental conditions. Analyses of the sediments, macrofossils, incorporated pollen and non-pollen microfossils including dinoflagellate cysts, diatoms and algal cysts within lacustrine, freshwater marsh and marine lagoon environments are integrated to maximise the palaeoenvironmental information obtained. These analyses are interpreted together with archaeological data to reconstruct spatial differences in Holocene environmental change in the study-area. Holocene sedimentary sequences are determined and a record of vegetation change since the mid-Holocene in the study-area is interpreted from palynological analyses. In contrast to most studies of Holocene vegetation history in Italy, the sharp decline in woodland vegetation in the middle to late Holocene, is primarily attributed to human activities rather than climatic change. Palynological and archaeological evidence point to continuing relative sea-level rise in the past two millennia, an important factor in the development of coastal marsh in the study-area.