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Abstract: The climatic and anthropogenic control on Holocene sediment dynamics was not well constrained for the Western Mediterranean basin. The paucity of high resolution palaeoenvironmental records long hampered a detailed understanding of the human impact on erosion rates. This paper analyses Holocene sediment dynamics in the context of regional climatic conditions, land cover and human occupation based on an extended compilation of recently published high-resolution paleoenvironmental proxy data from both terrestrial and marine environments. The palaeoenvironmental reconstruction identified four main aridification episodes (A) at 5600–4700 (A4), 4100–3400 (A3), 2800–2500 (A2), and 1900–1300/1200 (A1) cal. BP. Most of the severe aridification phases were climatically induced, not human-driven and well correlated with a large dataset of paleoenvironmental records from the Western Mediterranean Basin and North Atlantic Ocean. The phases of enhanced aridity are generally associated with enhanced sediment dynamics, independent of the intensity and type of human occupation. In contrast, wet climatic conditions are found to be associated with both high and low sediment dynamics dependent on the human impact on the environment. The mid-late Phoenician, Phoenician II/Republican Rome civilizations and the Christian Reconquest are all associated with high human impact on the environment, and high erosion rates are reported for the Vera basin and NE Spain despite the improved hydrological conditions. Human occupation is not necessarily associated with geomorphic instability, as shown by the Post Argaric, Omeya and Nazarene periods that are characterized by low erosion rates and geomorphic stability. [Copyright &y& Elsevier]

Abstract: This paper highlights results of a multidisciplinary and multi-analytical study of Holocene archaeological soils around Cecita Lake (Sila massif, Calabria, southern Italy), which represents a typical upland Mediterranean environment. It is focused on assessment of climatic and environmental changes that took place since late Neolithic to Roman times, trying to discriminate natural from anthropogenic signals. Based on an integration of archaeological, geomorphological, stratigraphic, pedological, volcanological and soil charcoal (pedoanthracological) data, the following paleoclimatic/environmental reconstruction is proposed: a warm and humid, seasonally contrasted climate, with an overall geomorphological stability suited for soil development, characterized the late prehistoric environment (Holocene climatic optimum), dominated by a widespread oak forest. The main pedogenetic processes consisted in organic matter accumulation, clay illuviation, phyllosilicate and short-range order mineral neogenesis from weathering of granite and volcanic ash, sourced from late Pleistocene–Holocene eruptions of the Aeolian Islands. One or more mid-Holocene episodes of climate deterioration towards drier conditions (indicated by a decrease of clay translocation processes and possible irreversible dehydration of poorly-crystalline aluminosilicates into phyllosilicate clay minerals) promoted intense land degradation. This was in turn enhanced by increasing human activities for settlement and resource exploitation (among which deforestation and ploughing for agriculture), which led to a shift of the vegetation cover towards a dominant pine forest between 3 ka BP and the Roman epoch. Humid and possibly cooler climatic conditions during the late Holocene are indicated by the decrease of clay illuviation, coupled with short-range order components prevailing over phyllosilicate clays during Roman soil formation. [Copyright &y& Elsevier]