Historical reconstruction (1860-2018) of soil erosion rates

The reconstruction of past erosion rates takes into account changes in Land Cover (C-factor) and precipitation intensity (R-factor). The topography, soil conditions and management factors (K, LS, and P) were assumed constant for the whole period 1860–2018.

For the erosion rates, figures (below) present the historical spatio-temporal variability reconstructed. On the top subfigures(below) , the absolute erosion rates in 1860 are shown on the left, while the maps for 1910, 1960, and 2010 represent the variation with respect to 1860. It can be seen that the annual variations do not follow a linear pattern through time, thus affecting erosion calculations unequally. A decrease in erosion rates from 1860 to 2010 can be noted in Central Europe, and a strong pattern on countries' borders follows from the assumptions of the reconstructed land cover database used  (ORCHIDEE land cover reconstruction).

The R factor shows a cyclic pattern from 1860 to 1901 due to the recycling of (i.e., repetition of climate) forcings adopted by ORCHIDEE for this period. The calculations also indicate an overall increase in erosion rates from 1860 to 1960 due mainly to land cover changes and a peak in rainfall erosivity. The increase trend follow the land cover changes in Europe as the agricultural intensification has contributed to convert forestlands and grasslands to croplands after 1950's-1960's.

The main source for calculations of R-factor was the monthly erosivity datasets in EU. To extrapolate for the past, we assumed a constant erosivity density for the whole simulation period, 1860–2018. The land cover map is based on ORCHIDEE land cover reconstruction. The reconstruction of C-factor needed with an additional procedure to minimize the differences arising from the mismatch in the land cover class definitions (C-factor) and spatial resolution. Such a procedure consisted of fitting a linear regression model to the upscaled version of the original C factor using the target land cover classes as explanatory variables.

More information:
ORCHIDEE Land Cover Reconstuction:  https://orchidas.lsce.ipsl.fr/dev/lccci/

Data:
Download the data aggregated as average loss per dcade. In addition, we provide both the annual and monthly soil erosion reconstruction data (1860-2018)

References:
Fendrich, A.N., Ciais, P., Lugato, E., Carozzi, M., Guenet, B., Borrelli, P., Naipal, V., McGrath, M., Martin, P. and Panagos, P., 2022. Matrix representation of lateral soil movements: scaling and calibrating CE-DYNAM (v2) at a continental level. Geoscientific Model Development, 15: 7835–7857.

Reconstruction maps of soil erosion rates (1860-2018)

Trends of soil loss by water erosion, C-factor and R-factor (1860-2018)