수도의 카드뮴 흡수이행에 대한 물관리 및 개량제 시용효과

The Effect of Irrigation Control and the Application of Soil Ameliorators on Cadmium Uptake in Paddy Rice

수도에서 카드뮴의 흡수양상과 물관리 및 토양개량제 사용에 따른 흡수경감효과를 구명하기 위하여 카드뮴이 $0.01mg\;l^{-1}$로 함유된 물을 개량제인 유기물, 석회, 규산 및 인산을 처리한 모양에 상시담수 및 간단관수로 조절하여 포트 시험한 결과는 다음과 같다. 생육시기별 토양의 pH는 유수형성기에 가장 높았고 Eh는 생육이 진행될수록 낮았으며 상시담수구에서 낮게 나타났다. 생육중기의 벼 경엽 및 뿌리의 카드뮴함량은 간단관수보다 상시담수구에서 낮았고 상시담수구중 규산 및 석회시용구에서 흡수저감 효과가 크게 나타났다. 벼 생육기의 토양 pH는 경엽 및 현미의 카드뮴함량과 부의 상관, Eh는 정의 상관을 보였고 수확후 경엽과 현미중의 카드뮴함량은 간단관수보다 상시담수에서 낮았고 상시담수구중 석회 및 유기물 병용구에서 흡수 저감효과가 크게 나타났다. 시험후 토양의 pH는 3요소 및 인산시용구를 제외하고 pH6.0 이상이였고 카드뮴함량은 석회, 유기물, 규산 단독 및 병용처리구가 낮게 나타났다.

In order to identify the effect of cadmium uptake by soil ameliorators in rice plants, compost, lime, silicate, and phosphate were treated. Plants were grown with irrigation water containing $0.01mg\;l^{-1}$ cadmium and treated with two irrigation systems, intermittent irrigation and continuous submersion. Soil pH was higher at the panicle formation stage compared to other growing stages. However, Eh value was decreased as growing stage was proceeded. Eh values measured at the continuous submersion plots were lower than those at the intermittent irrigation plots. Cadmium contents in the both leaves and roots of rice plants grown at the continuous submersion plots were lower than intermittent irrigation plots in the middle of growing season. Among the continuous submersion plots, cadmium uptake was highly reduced at the both silicate and lime treated plot compared to other treatments. In the harvest season, cadmium contents in the both leaves and brown rice were higher at the intermittent irrigation plots than the continuous submersion plots. Cadmium uptake was highly reduced at the compost and lime mixture plot compared to other treatments among the continuous submersion plots. Soil pH was negatively correlated with the cadmium contents of the both shoot and brown rice while Eh was positively correlated with those. The cadmium content of shoot was positively correlated with that of brown rice in the harvest season.