Relationships of 137Cs inventory with magnetic measures of calcareous soils of hilly region in Iran

Erosion is a natural process, but it has been dramatically increased by human activities; and this adversely influences soil productivity and environmental quality. For quantification of soil erosion, several techniques including the use of Cs-137 have been employed. This study was conducted to explore the relationships of Cs-137 inventory with magnetic properties in calcareous soils in western Iran. Ten transects were selected in the hilly region in Chelgerd district of Iran. Soil samples from 0 to 30 and 30 -50 cm depths were collected from fifty points to determine Cs-137 inventory, magnetic measures and selected physico-chemical properties (in total there were 100 soil samples). The results showed that simple mass balance model (SMBM) estimated a gross erosion rate of 29.6 t ha(-1) yr(-1) and a net soil deposition of 21.8 t ha(-1) yr(-1); hence, a net soil loss of 9.6 t ha(-1) yr(-1) and a sediment delivery ratio of 31.4%. Simple linear regression and non-linear regression analysis showed that mass magnetic susceptibility (chi(lf)) explained only 33.64% and 45% of variability in Cs-137 in the transects studied. The results of multiple linear regression analysis of Cs-137 with magnetic parameters and physico-chemical properties indicated that extractable potassium and chi(lf) explained approximately 61% of the total variability in Cs-137 in the area studied. Overall, the results suggest that further research is needed for the use of magnetic characteristics as an alternative technique in place Cs-137 methodology for calcareous soils. (c) 2012 Elsevier Ltd. All rights reserved.