School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China.
J Contam Hydrol. 2011 Apr 1;123(1-2):75-81. doi: 10.1016/j.jconhyd.2010.12.008. Epub 2010 Dec 25.
The effects of charcoal amendment on adsorption, leaching and degradation of the herbicide isoproturon in soils were studied under laboratory conditions. The adsorption data all fitted well with the Freundlich empirical equation. It was found that the adsorption of isoproturon in soils increased with the rate of charcoal amended (correlation coefficient r=0.957**, P<0.01). The amount of isoproturon in leachate decreased with the increase of the amount of charcoal addition to soil column, while the retention of isoproturon in soils increased with an increase in the charcoal content of soil samples. Biodegradation was still the most significant mechanism for isoproturon dissipation from soil. Charcoal amendment greatly reduced the biodegradation of isoproturon in soils. The half-lives of isoproturon degradation (DT(50)) in soils greatly extended when the rate of added charcoal increased from 0 to 50 g kg(-1) (for Paddy soil, DT(50) values increased from 54.6 to 71.4 days; for Alfisol, DT(50) from 16.0 to 136 days; and for Vertisol, DT(50) from 15.2 to 107 days). The degradation rate of isoproturon in soils was significantly negatively correlated with the amount of added charcoal. This research suggests that charcoal amendment may be an effective management practice for reducing pesticide leaching and enhancing its persistence in soils.
在实验室条件下研究了木炭改良剂对土壤中除草剂异丙隆的吸附、淋溶和降解的影响。吸附数据均符合 Freundlich 经验方程。结果表明，土壤中异丙隆的吸附随木炭添加率的增加而增加（相关系数 r=0.957**，P<0.01）。随着土壤柱中添加的木炭量的增加，淋出液中异丙隆的量减少，而土壤中异丙隆的保留量随着土壤样品中木炭含量的增加而增加。生物降解仍然是土壤中异丙隆降解的最主要机制。木炭改良剂大大降低了土壤中异丙隆的生物降解。当添加的木炭率从 0 增加到 50 g kg(-1)时，土壤中异丙隆降解的半衰期（DT(50)）大大延长（对于水稻土，DT(50)值从 54.6 天增加到 71.4 天；对于 Alfisol，DT(50)从 16.0 天增加到 136 天；对于 Vertisol，DT(50)从 15.2 天增加到 107 天）。土壤中异丙隆的降解速率与添加的木炭量呈显著负相关。本研究表明，木炭改良剂可能是一种减少农药淋溶和增强其在土壤中持久性的有效管理措施。
