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This paper presents a new correlation of Late and Middle Pleistocene fluvial sedimentary sequences in Greek, Libyan and Spanish river basins and evaluates river response to climate change over the Last Interglacial-Glacial Cycle. Over the past 200,000 years there have been at least 13 major alluviation episodes in the Mediterranean, although the amplitude, frequency and possibly, duration of these events varied significantly across the region. Parts of Oxygen Isotope Stage (OIS) 5 appears to have been periods of pronounced landscape change in many Mediterranean catchments with major river aggradation occurring at B109-111 ka (during OIS 5d) and most notably at B88 ka (OIS 5b/5a boundary). Other parts of OIS 5 appear to have been periods of relative fluvial inactivity. OIS 2 and 3 were both characterised by an apparent increase in the number of alluviation events, and this record of river behaviour parallels many other palaeoenvironmental records in the region which also show more frequent climate fluctuations between B12 and 65 ka. There is evidence for a high degree of synchrony in major river aggradation events across the Mediterranean in catchments with very different sizes, tectonic regimes and histories. Climate-related changes in catchment hydrology and vegetation cover over the last 200 ka would appear to be the primary control of large-scale (catchment wide) sedimentation over time periods of between 10 3 and 10 4 years. r

Glacial and periglacial landforms are widespread in the mountains of the Mediterranean region. The evidence for glacial and periglacial activity has been studied for over 120 years and it is possible to identify three phases of development in this area of research. First, a pioneer phase characterized by initial descriptive observations of glacial landforms; second, a mapping phase whereby the detailed distribution of glacial landforms and sediments have been depicted on geomorphological maps; and, third, an advanced phase characterized by detailed understanding of the geochronology of glacial sequences using radiometric dating alongside detailed sedimentological and stratigraphical analyses. It is only relatively recently that studies of glaciated mountain terrains in the Mediterranean region have reached an advanced phase and it is now clear from radiometric dating programmes that the Mediterranean mountains have been glaciated during multiple glacial cycles. The most extensive phases of glaciation appear to have occurred during the Middle Pleistocene. This represents a major shift from earlier work whereby many glacial sequences were assumed to have formed during the last cold stage. Glacial and periglacial deposits from multiple Quaternary cold stages constitute a valuable palaeoclimatic record. This is especially so in the Mediterranean mountains, since mountain glaciers in this latitudinal zone would have been particularly sensitive to changes in the global climate system.

The provenance pattern of Nile River sediments can be used as a proxy for paleoclimatic changes in East Africa. The 87 Sr/ 86 Sr ratios are particularly appropriate for such provenance investigations, because the White Nile drains predominantly crystalline basement rocks, whereas the Blue Nile and Atbara flow off the Ethiopian Highlands, which consist of Tertiary volcanic rocks. A high-resolution profile of 87 Sr/ 86 Sr and Ti/Al ratios from a well-dated core in the Nile Delta shows a close correspondence with known changes in Nile flow over the past 7000 yr. At times of higher river flow there was markedly decreased input of Blue Nile-derived and total sediment. This change was caused by northward movement of the Inter Tropical Convergence Zone, resulting in increased vegetative cover in the Ethiopian Highlands due to higher rainfall and a longer wet season. This inverse relationship between Nile River flow and sediment flux may have had important implications in the development of agricultural technology in ancient Egypt. The marked minimum in 87 Sr/ 86 Sr at 4200-4500 yr B.P. is coincident with the end of the Old Kingdom in Egypt and provides independent evidence that demise of the Old Kingdom might have been associated with an extended period of catastrophic low floods. During the Quaternary and late Neogene, there was periodic deposition of organic-rich sediments (sapropels) in the eastern Mediterranean that represent important indicators of major environmental change. Evidence from the Ti/Al ratio suggests that the pattern of erosion and sediment supply from the Nile catchment observed in this study also occurred throughout much of the Neogene and Quaternary. The reduced inputs of Blue Nile sediment during times of sapropel formation contributed to the increased primary productivity by reducing the amount of phosphate removed on particles and to the observed change to N limitation in the eastern Mediterranean, which are important characteristics of sapropel deposition.