비교란 Lysimeter를 활용한 논 토양에서의 살충제 Tricyclazole의 용탈특성

This study was conducted to investigate the leaching characteristics of insecticide tricyclazole 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. Tricyclazole 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 tricyclazole 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 tricyclazole analysis in water sample. Recovery and limit of quantitation (LOQ) of tricyclazole in water were 107.9-114.9% 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 tricyclazole (treatment content 770.57 mg) during experiment period in sandy loam, loam, and silty clay loam lysimeter were 0, 12.37, and 13.72 mg, respectively. Most of leached tricyclazole were detected at early stage of experiment in loam and silty clay loam lysimeters. These results showed that the movement of tricyclazole in sandy loam, loam, and silty clay loam paddy soil was very high.