Effects of Soil Amendments Application on Growth of Rice Cultivated in Soils Polluted with Heavy Metal(loid) and on the As and Cd Content in Brown Rice

Abstract

Heavy metal(loid) contamination of rice is the main issue in abandoned metal mine area with regard to food safety. A field study was conducted in mine area to see if soil amendments treatment including calcium superphosphate, sulfur, steel slag and S-containing fertilizer could reduce As and/or Cd content in rice grain and increase the growth of rice. The As content in brown rice reduced to 60% compared to the control only in <TEX>$7.0Mg\;ha^{-1}$</TEX> of steel slag treatment. Cd reduction in rice was thought to be not the effect of amendments but the result from the difference in growth and development of rice plant and this could be ascribed to low soil Cd availability to rice plant. Compared with control, increased rice yield of cultivar Hwanggeumnuri was 1.3~2.2 and <TEX>$1.5Mg\;ha^{-1}$</TEX> in calcium super phosphate and S-containing fertilizer treatment, respectively and the trend was also observed in cultivar Ungwang. However, steel slag treatment reduced the Ungwang yield by <TEX>$0.4{\sim}0.9Mg\;ha^{-1}$</TEX>. Future work will be needed to establish the agricultural measure with which secure the safety and yield of rice simultaneously.