Atmospheric CO2 Level and Temperature Affect Degradation of Pretilachlor and Butachlor in Indian Soil

This study was conducted at ambient (398 ± 10 µmol mol −1 ), elevated (450 ± 10 µmol mol −1 ) and elevated (550 ± 10 µmol mol −1 ) atmospheric CO 2 under three moisture regime and also three level of temperature (4, 25, and 40°C) to assess the degradation of pretilachlor and butachlor. Under dry condition at 398 ± 10 µmol mol −1 , T 1/2 was 28.5 and 59.4 days for pretilachlor and butachlor, respectively; slowly decreased to 18.2 and 44.5 days at 550 ± 10 µmol mol −1 indicated that elevated condition enhanced degradation than ambient condition. Under field capacity with increasing CO 2 levels from ambient to elevated, T 1/2 decreased from 18.9 to 11.6 days and 39.4 to 16.2 days for of pretilachlor and butachlor, respectively. Similarly, under submerged conditions with increasing CO 2 levels T 1/2 decreased 14.7–7.1 and 26.3–11.8 days for pretilachlor and butachlor, respectively. Study also revealed that both pretilachlor and butachlor dissipated faster at 40°C (T 1/2 , 9.7 and 19.4 days) than 25°C (T 1/2 , 16.2 and 36.7 days). Slower dissipation was recorded at 4°C (T 1/2 , 87.6 and 182.4 days).