Dissipation of Insecticide Carbaryl in Tea Garden Soils

• Main Authors: Liang, Ya Fang, 梁雅芳
• Other Authors: Ph. D Yei-Shung Wang
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/82216413750536715694

碩士 === 國立臺灣大學 === 農業化學研究所 === 90 === Abstract The fates of insecticide carbaryl in six soils of Taiwan tea garden were studied. The tea garden soils were collected from Tachichiao(Ctg), Ku-ting Pen1(Kip1), Ku-ting Pen2(Kip2), Kuei Kou(Kuk), Chentoushan(Ct), and Shin Keng Shan(Ske). In these soils, the organic matter contents were quite different. The dissipation of carbaryl in six tea garden soils was effected by soil organic matter, cation exchange capacity soil pH, and the soil particle content of clay. In Ctg, Kip1, Kuk, Ct, and Ske soils, the half-lives of carbaryl increased with the incubation temperature and the soil water content. But in the Kip2 soil, there was no effected on the half-life of carbaryl by increasing the incubation temperature and the soil water content. In the Kip2 soil the highest amounts of organic matter content, showed 50% carbaryl residue in the soil until the end of experiments. The sorption isotherm of the carbaryl were fitted with linear and Freundlich equation in six tea garden soils and the square of correlation coefficient R2 is above 0.95. In the constant (linear) equation, the adsorption constant (Kd) values were presented as follows, Kuk 14.09 L/Kg、Ct 7.45 L/Kg、 Kip2 5.74 L/Kg、 Ske 3.87 L/Kg、 Kip1 1.93 L/Kg and Ctg 1.63 L/Kg. Using the screen model of BAM to simulate the carbaryl behavior in six tea garden soils, and using the screen model of GWP to simulate the time of carbaryl reach to ground water were performed in the study. In the result of BAM model, carbaryl was remained in the upper top layer of six tea garden soils (35 cm). In the GWP model, using the middle values of six tea garden soil characterizes had a good simulated to present the probability of carbaryl reach to the ground water.