Buried soils of floodplains and paleoenvironmental changes in the Holocene

Abstract

Sequences of buried soils were studied in the floodplains of the Oka and Moscow rivers. These soils were formed in the periods of low floods, when alluvial sedimentation was inactive. Numerous ¹⁴C and archaeological dates indicate the following intervals of intensive soil formation on the floodplains of the Oka River: 6,500–4,500; 4,000–3,000; and 2,200–800 yr BP. In many cases, buried Gleysols and Phaeozems of the middle Holocene are replaced by Luvisols of the late Holocene. Deforestation and extensive tillage in the river basins during the last 700–900 years has caused an increase in the rates of spring runoff, slope erosion, and alluviation on the floodplains under conditions of active and high-level floods. As a result, Luvisols have been buried under recent alluvium, on top of which weakly developed Fluvisols are forming.