Herbicde application may affect dissolved oxygen DO, dissolved carbon dioxde and in ponded water, and of the water which is the water aerated with the atmoosphere.ln the presentstudy,DO concentration did not reach supersaturated state after herbicide application,and variation in DO decreased. The herbicide application reduced the diurnal variation in dissolved and increased the overall concentration,During the day, before the herbicide application, variaons in and were large,with highre than allowing absorption of from the air,whereas at night,the relationship between in