DDTs contents in the surface sediment samples taken from 12 reservoirs and 2 lakes were measured by GC-ECD.

• 2004年秋季采集了河北12个水库和2个湖泊的表层沉积物样品；利用GC-ECD测定DDTs农药的含量；在此基础上分析了其残留与组成特征以及生态风险.