Considering lacustrine erosion records and the De Ploey erosion model in an examination of mountain catchment erosion susceptibility and precipitation reconstruction

Abstract

Reconstruction of paleo-precipitation can provide an insight into past climate and precipitation. De Ploey et al. (1995) presents a highly simplified erosion equation to consider precipitation and erosion susceptibility. This empirical model allows estimation of total precipitation and erosion susceptibility across a range of catchment characteristics (including catchment area, slope, elevation, vegetation cover) and when limited catchment or meteorological data is available. The presented study tests the De Ploey equation using dated lacustrine records of catchment soil deposition both spatially and temporally. The objective is to examine the De Ploey equation’s ability and efficiency in reconstructing past long-term precipitation using sedimentological parameters. The erosion susceptibility factor is described as a ‘black box’ value by De Ploey et al. (1995). This research unravels the erosion susceptibility variable, identifying it to change spatially and temporally according to precipitation, vegetation cover and composition (the extent of tree establishment across the catchment), total lacustrine deposition and geochemical signatures in the archive. Calculation of the erosion sustainability variable and it’s use within the De Ploey erosion equation illustrate a reconstruction of an indicative mean annual precipitation and erosion susceptibility change over the recent period (∼100 years).