Radioactive Cesium and Potassium Absorbability of Eight Forage Grass (Poaceae) Species

Abstract

Additional potassium fertilization is an effective measure for reducing radioactive cesium (RCs) transfer from soil to grass. However, increased potassium fertilizer use is often avoided as it may increase livestock disease risk. We conducted a two-year study of eight grass species and determined that transfer factor and pasture potassium content of festulolium (× Festulolium Braunii) and tall fescue (Festuca arundinacea Schreb.) were consistently lower than that of orchardgrass (Dactylis glomerata L.). The generalized linear model analysis indicated that the transfer factor and grass potassium content compared to orchardgrass were 52.2% and 86.3% for festulolium and 35.6% and 84.8% for tall fescue, respectively. These two grass species have high reliability as low RCs-uptake species, and therefore, changing the grass species from orchardgrass to festulolium or tall fescue can be an effective strategy for reducing RCs transfer without increasing the grass potassium content.