The adsorption and leaching characteristics of five ionic pesticides including four acidic pesticides (2,4-D, dicamba, MCPA, and MCPP) and one amphoteric pesticide (imazaquin) in agricultural soils were investigated. Soils around spring waters that were heavily affected by pesticide run-off and soils around wells considering the regional characteristics in Jeju Island were collected at 24 stations. The Freundlich constant, KF value, which is a measure of the adsorption capacity, decreased in the order of 2,4-D > MCPA > MCPP > dicamba > imazaquin. The adsorption capacity of these ionic pesticides decreased with increasing pH owing to the effects of ionization of pesticides and different ionizable functional groups of soils. The leaching of ionic pesticides in the soil column showed a reverse relationship with their adsorption in soils, namely, the ionic pesticides were leached more quickly for the pesticides with lower adsorption capacity. The groundwater contamination potential of the ionic pesticides was evaluated in the order of imazaquin > MCPA > MCPP > dicamba > 2.4-D according to the groundwater ubiquity score based on soil Koc and the half-life of the pesticide.

Abstract
1. 서 론
2. 재료 및 방법
    2.1. 토양시료 및 농약
    2.2. 실험 방법
3. 결과 및 고찰
    3.1. 토양 중 이온계 농약의 흡착 특성
    3.2. 토양 중 이온계 농약의 용탈특성
    3.3. 이온계 농약의 지하수 잠재 위험성 평가
4. 결 론
REFERENCES

• 전시범(제주대학교 생명과학기술혁신센터) | Si-Bum Chun (Jeju National University Biotechnology Regional Innovation Center)
• 현익현(제주특별자치도 보건환경연구원) | Ik-Hyun Hyun (Research Institute of Health & Environment, Jeju Special-Governing Province)
• 감상규(제주대학교 환경공학과) | Sang-Kyu Kam (Department of Environmental Engineering, Jeju National University) Corresponding author