| Time (year) | Sample Location | Degradation Dynamics Equation | Correlation Coefficient | Half-Life (d) |
| 2011 | Yangzhou | Ct = 1.8131e−0.1352t | 0.9770 | 5.13 |
| Jingzhou | Ct = 1.9875e−0.1389t | 0.9804 | 4.99 | |
| 2012 | Yangzhou | Ct = 2.0251e−0.1569t | 0.9797 | 4.42 |
| Jingzhou | Ct = 1.8051e−0.1586t | 0.9863 | 4.37 |