논토양에서 질산 이온이 철의 환원과 인의 용출에 미치는 영향 (Effect of Nitrate on Iron Reduction and Phosphorus Release in Flooded Paddy Soil)

서지정보

· 발행기관 : 한국환경농학회
· 수록지 정보 : 한국환경농학회지 / 28권 / 2호 / 165 ~ 170페이지
· 저자명 : 정종배

초록

The increase in P availability to rice under flooded soil conditions involves the reductive dissolution of iron phosphate and iron (hydr)oxide phosphate. However, since NO3- is a more favourable electron acceptor in anaerobic soils than Fe, high NO3- loads function as a redox buffer limiting the reduction of Fe. The effect of adding NO3- on Fe reduction and P release in paddy soil was investigated. Pot experiment was conducted where NO3- was added to flooded soil and changes of redox potential and Fe2+, NO3-, and PO43- concentrations in soil solution at 10 cm depth were monitored as a function of time. Redox potential decreased with time to –96 mV, but it was temporarily poised at about 330~360 mV when NO3- was present. Nitrate addition to soil led to reduced release of Fe2+ and prevented the solubilization of P. Phosphate in pore water began to rise soon after incubation and reached final concentrations about 0.82 mg P/L in the soil without NO3- addition. But, in the soil with NO3- addition, PO43- in pore water was maintained in the range of 0.2~0.3 mg P/L. The duration of inhibition in Fe2+ release was closely related to the presence of NO3-, and the timing of PO43- release was inversely related to the NO3- concentration in soil solution. The results suggest that preferential use of NO3- as an electron acceptor in anaerobic soil condition can strongly limit Fe reduction and P solubilization.

영어초록

The increase in P availability to rice under flooded soil conditions involves the reductive dissolution of iron phosphate and iron (hydr)oxide phosphate. However, since NO3- is a more favourable electron acceptor in anaerobic soils than Fe, high NO3- loads function as a redox buffer limiting the reduction of Fe. The effect of adding NO3- on Fe reduction and P release in paddy soil was investigated. Pot experiment was conducted where NO3- was added to flooded soil and changes of redox potential and Fe2+, NO3-, and PO43- concentrations in soil solution at 10 cm depth were monitored as a function of time. Redox potential decreased with time to –96 mV, but it was temporarily poised at about 330~360 mV when NO3- was present. Nitrate addition to soil led to reduced release of Fe2+ and prevented the solubilization of P. Phosphate in pore water began to rise soon after incubation and reached final concentrations about 0.82 mg P/L in the soil without NO3- addition. But, in the soil with NO3- addition, PO43- in pore water was maintained in the range of 0.2~0.3 mg P/L. The duration of inhibition in Fe2+ release was closely related to the presence of NO3-, and the timing of PO43- release was inversely related to the NO3- concentration in soil solution. The results suggest that preferential use of NO3- as an electron acceptor in anaerobic soil condition can strongly limit Fe reduction and P solubilization.

참고자료

· 없음