Revisiting the time of the last mass straightening bends on the upper Kama

Abstract

The scientists investigating channels and palaeographers still do not have a clear answer to the question when the last mass channel directional change processes started on the upper Kama and its tributaries. Distinct morphometrical parameters of numerous ox-bows, now located along relatively straight channel parts and at the same time absence of imperforation (ageing) signs do not allow to makes unambiguous conclusions about the duration of directional straightening of the river and major restructuring of the floodplain-channel complexes. Finding the answer to this question included: a) the analysis of historical documents and local folklore that mention change in the location (removal) of the Kama channel; b) comparison of the degree of the Kama ox-bows imperforation and peat overgrowing with the standard peat accumulation rates under the conditions of taiga landscapes. According to the results of complex analysis the following suggestion has been made – the beginning of the last mass straightening bends of the upper Kama was in the second half the Subatlantic period.