The Varying Impact of Land Use and Climate in Holocene Landscape Dynamics in the Mezzogiorno

The relative relationship of Holocene climate change, human cultures, and landscape evolution is unclear. However, palaeoecological and archaeological records, suggest that both have played an important role, acting in combination to varying degrees through time, to affect landscape dynamics. The country straddling the Puglia and Basilicata border region in southern Italy (the Mezzogiorno) is a landscape particularly sensitive to erosional processes, and provides an ideal area where these relationships can be studied. In addition, the affects of climate change in this area are magnified by poor land use practices that are being applied to an unstable, and easily erodible, surface geology. Moreover recent palaeoecological and archaeological research in this hilly country is also providing vital information regarding the role of climate and people in landscape dynamics. Four summers of preliminary research with a team consisting of a paleoecologist/geomorphologist, archaeologist, and a dendroclimatologist, has begun reconstruction of a full Holocene climate history from the records of alluvial erosion/deposition, spring discharge, and soil formation. These will aid in determing how climate, and human demography in the Puglia/Basilicata region relate to landscape dynamics. Archaeological surveys have already mapped the varying spatial distribution of cultural materials, providing an assessment of where people lived, population sizes, and their activities during the Holocene. Numerous dated erosion/deposition sequences in alluvium and valley terrace exposures along the Basentello/Bradano River valley detail the regional record of erosional cycles. Dated spring discharge events are beginning to record groundwater recharge linked either to climate, or to deforestation. In addition, dated soil formation episodes are evidence episodes of ground surface stability. A macrophysical climate model of local past effective precipitation is being used to reconstruct cycles of past erosion. These understandings are being used to predict future outcomes of global climate change.