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Alluvial deposits of the Loire/Arroux trunk/tributary system record distinct, synchronous episodes of regional fluvial adjustment. Changes in fades and depositional style through time can be interpreted with a modern analogue model that relates vegetative cover/human influence with sediment supply, and modes of atmospheric circulation with the paths and styles of storms that drive variable discharge regimes across western Europe. Zonal atmospheric circulation results in a Mediterranean style climate over southern Burgundy, producing dry conditions punctuated by infrequent, large floods. Episodic overbank sedimentation and the burial of thin paleosols in sandy overbank facies is indicative of this style of fluvial activity, ca 1300 years BP. Humans may have increased the available volume of fine grained sediment at this times through increased agricultural activity along valley axes, however facies match that expected from a 'flashy' discharge regime. In contrast, meridional circulation patterns result in a maritime style climate over southern Burgundy, with the intrusion of storms, moist conditions and frequent, moderate magnitude discharges. Wide, deep channels, thick channel facies and thin overbank facies are indicative of this style of fluvial activity, recorded in deposits dating to ca 4050 to 3200 years BP. Strong meridional conditions and extreme climatic variability during the Little Ice Age resulted in very large discharges that straightened and widened channels, while scouring and obscuring older terraces (ca 500 years BP). Deposition over the last two centuries is related to increasingly zonal circulation and infrequent, large (over-bank) floods. Changes in fluvial dynamics over the last 300 years can be attributed primarily to climatic control, as there has been very little change in land-use over that period.

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Interpretation of satellite imagery, field mapping, stratigraphie and sedimentologic investigations, and a series of radiocarbon and optically- stimulated luminescence dates (OSL) define a record of Late Pleistocene and Holocene landscape change along 100 km of the Loire and Arroux Rivers in southern Burgundy, France. Seven informally designated allostratigraphic units have been differentiated, each representing time periods when rivers were adjusted to prevailing hydrological regimes. Surface morphology of Late- and Post-glacial deposits are well-preserved, showing a distinct trend from braided to meandering channel plan-forms, coupled with overall decreases in channel amplitude and sinuosity through time. Two distinct Late-Pleistocene braided stream channel deposits were emplaced ca. 86-40 ka and 23-1 1 ka, followed by a post-glacial transition to a meandering regime between 11 ka and 7,3 ka. Mid-Late Holocene units show evidence of increasing amounts of overbank deposition, with a peak in fluvial activity ca 3 ka. The youngest meanderbelt terminated around 1.53 ka, coincident with channel straightening, in-filling of abandoned channels, and development of the present gravelly meandering pattern.