Anthropogenic and climatic impact on Holocene sediment dynamics in SE Spain: A review

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.