Centennial-scale late-Pleistocene to mid-Holocene synthetic profile of the Medjerda Valley, northern Tunisia

Abstract

During the late Pleistocene to mid-Holocene, the Medjerda river system in Mediterranean Tunisia shows events of increased flooding and aggradation of relatively coarse overbank deposits. Geomorphic activity in river systems within this region correlate with aridification of the climate, but not with temperature. The late-Pleistocene to mid-Holocene synthetic profile of the Ghardimaou floodplain (mid-Medjerda river) indicates fluvial activity from 12.4 to 11.8, 6.6 to 6.0 and after 4.8 ka cal. BP. External correlations imply global and regional causes of the late-Pleistocene to mid-Holocene climatic development such as North Atlantic deep-water formation, fluctuations in Saharan humidity and impacts of local Mediterranean weather phenomena. Palaeomagnetic records offer additional opportunities to interpret fluvial activity in river systems, especially for detecting chronological hiatuses in apparently homogeneous sediment sequences.

Regional fire history shows abrupt responses of Mediterranean ecosystems to centennial-scale climate change (Olea–Pistacia woodlands, NE Morocco)

“…As there is no evidence for human impact on Mid-Holocene fire regimes at the Lower Moulouya Basin, our findings suggest an abrupt climatic shift during the 5th to 4th millennium before present in this region (cf. Carrió n et al, 2003, in press;Roberts et al, 2004;Sadori et al, 2008;Wengler and Vernet, 1992;Zielhofer et al, 2004). …”

Holocene climate change, vegetation history and human impact in the Central Mediterranean: evidence from the Maltese Islands

“…BP, evidence for the major environmental shocks caused by the aridification events seen in North Africa (e.g. Faust et al, 2004;Zielhofer et al, 2004) and in Southern Europe (e.g. Magny et al, 2011;Sadori et al, 2011) is not forthcoming in the palaeoecological record from Malta ( Fig.…”

“…BP (e.g. Ouda et al, 1998;Hunt et al, 2001Hunt et al, , 2011aHunt et al, , 2011bZielhofer et al, 2002Zielhofer et al, , 2004Zielhofer et al, , 2008Marquer et al, 2008). Forest remained until the Greek period in the Gebel Akhdar in NE Libya (Hunt et al, 2002), but was eliminated by grazers and a climate change to more arid conditions in the Neolithic in NW Libya (Gilbertson and Hunt, 1996).…”

Combining allostratigraphic and lithostratigraphic perspectives to compile subregional records of fluvial responsiveness: The case of the sustainably entrenching Palancia River watershed (Mediterranean coast, NE Spain)

“…While attempting to provide regional to subcontinental syntheses at scales larger than 10 3 km 2 , many studies still refer to stratigraphic sequences from one or a few, selected floodplain stretches, i.e., information from a small proportion of depositional settings is applied to interpret macroscale watershed condition (e.g., Pope et al, 2003;Faust et al, 2004;Zielhofer et al, 2004;El Amrani et al, 2008). Another approach is through assimilating stratigraphic information from a variety of geographic locations (e.g., Vita-Finzi, 1969, 1976Macklin et al, 2002;Santisteban and Schulte, 2007), which involves the risk of correlating physiographically diverse settings that may respond differently to similar trends in regional to subcontinental climatic or tectonic forcing.…”