Abstract

Fertilization of soils contaminated by radionuclides with potassium (K) and its effect on Cs-137 transfer from soil to crops is well studied in field conditions; however experiments over many years are few.The effects of potassium fertilization on cesium-137 (Cs-137) transfer to hay, pasture grass, and barley growing on organic rich soils and mineral sand and loam soils in a number of field experimental sites situated in different environments in Sweden are summarized and discussed. The basic experimental treatments were control (no K fertilizers were applied), 50, 100, and 200 kg K ha(-1). In the experiment, which lasted over 3-6 years, Cs-137 transfer factors in control treatments ranged between 0.0004 m(2) kg(-1) (barley grain on sand soil) and 0.07 m(2) kg(-1) (pasture grass on organic rich soil). Potassium application on soils with low clay content i.e. mineral sand and organic rich soils was effective at the 50-100 kg ha(-1) level. Application of 200 kg K ha(-1) resulted in a five-fold reduction in Cs-137 transfer for hay and up to four-fold for barley grain. The effects of potassium application were generally greater on sand than organic rich soil and were observed already in the first cut. After K application, the reduction in Cs-137 transfer to crops was correlated with Cs-137:K ratios in plant material. Additional application of zeolite caused a 1.4 reduction of Cs-137 transfer to hay on sand and 1.8-fold reduction on organic rich soil; whereas, application of potash-magnesia and CaO had no effect. (C) 2013 Elsevier Ltd. All rights reserved.

Keywords

Countermeasures; Radiocesium; Potassium; Pasture grass; Soil

Published in

Journal of Environmental Radioactivity
2014, volume: 130, pages: 22-32
Publisher: ELSEVIER SCI LTD

Authors' information