The 137Cs-method was used to obtain long-term
estimates of soil erosion in the Jaslovske Bohunice
site, a representative hilly loess cultivated area of Slovakia.
The estimated reference 137Cs inventory was
2910 Bqm−2, with a coefficient of variation of 4.3%.
Examination of the 137Cs redistribution in relation
to the topography of the study area revealed that,
within individual transects the 137Cs inventories are
closely related to major landforms. The 137Cs inventories
are considerably lower on the slopes than on the
plateau and they are highest in the valley. However,
when plotted against a selection of individual quantitative
slope parameters, i.e. the S and the LS factors
of the USLE or slope inclination, the correlations obtained
were weak.
The mean erosion rates estimated utilizing three
conversion models were 22.4 t ha−1 per year for the
PM, 35.6 t ha−1 per year for MBM1 and 17.3 t ha−1
per year for the MBM2. There is reasonable agreement
between the average of the mean erosion rates
obtained by the 137Cs-method (25.1 t ha−1 per year)
and the mean soil erosion rate obtained for small plots.
Nevertheless, further research on the application of
the 137Cs-method, in particular the validation of the
results obtained, is needed. Several issues requiring
further study have been highlighted.
With the available 137Cs data and the resulting estimates
of soil erosion/deposition rates it was possible
to produce maps illustrating the spatial distribution of
137Cs inventories and a three-dimensional representation
of soil erosion/deposition within the study area.