비교란 Lysimeter를 활용한 논 토양에서의 살균제 Pencycuron의 용탈특성

This study was conducted to investigate the leaching characteristics of fungicide pencycuron in paddy soil using undisturbed lysimeter. Soil horizons of sandy loam, loam, and silty clay loam lysimeter were composed of 6, 6, and 5, and clay contents were ranged from 53.1-63.2, 40.2-47.7, and 32.6-39.2 %, respectively. Bulk densities of each lysimeter were 1.38, 1.30, and 1.35 Mg/m3, respectively. Pencycuron was treated to each lysimeter at 15 days after rice planting, and water was supplied according to rice cultivation method. Pore volumes of sandy loam, loam, and silty clay loam lysimeter were calculated to 718.87, 764.15, and 735.85 L, and pore volume numbers of supplied water for rice cultivation were 0.98, 1.08, and 0.24, respectively. Movement of pencycuron in each lysimeter was investigated through the residue of it in 30, 55, 85, and 125 cm soil water from topsoil and leaching water. Gas chromatography (GC) was used for pencycuron analysis in water sample. Recovery and limit of quantitation (LOQ) of pencycuron in water were 72.8-84.0% and 3 μg/L. Changes of moisture tension, humidity, and temperature in sandy loam, loam, and silty clay loam lysimeter was not significantly different during experiment period. Weight of silty clay loam lysimeter was higher than other lysimeter because of less leaching. Leaching volume of sandy loam, loam, and silty clay loam lysimeter were 705.9, 828.7, and 174.5 L, respectively. Total leaching content of pencycuron (treatment content 770.57 mg) during experiment period in sandy loam, loam, and silty clay loam lysimeter were 0, 13.61, and 0.53 mg, respectively. These results showed that the movement of pencycuron in sandy loam and silty clay loam paddy soil was very low.