Thevenot Mathieu, Dousset Sylvie, Hertkorn Norbert, Schmitt-Kopplin Philippe, Andreux Francis
UMR 7618 INRA-CNRS-Université, Laboratoire de Biogéochimie et Ecologie des Milieux Continentaux, Centre INRA Versailles Grignon, Thiverval-Grignon, France.
Sci Total Environ. 2009 Jul 1;407(14):4297-302. doi: 10.1016/j.scitotenv.2009.04.021. Epub 2009 May 2.
Diuron is frequently detected in some drinking water reservoirs under the Burgundy vineyards, where organic amendments are applied. The environmental effect of these amendments on pesticide transport is ambiguous: on the one hand it could enhance their retention by increasing soil organic carbon content; on the other hand, dissolved organic matter (DOM) could facilitate their transport. Elutions were performed using columns packed with glass beads in order to investigate DOM-diuron interactions, and the possible co-transport of diuron and DOM. Four organic amendments (A, B, C and D) were tested; C and D were sampled at fresh (F) and mature (M) stages. An increase in diuron leaching was observed only for A and D(F) amendments (up to 16% compared to the DOM-free blank samples), suggesting a DOM effect on diuron transport. These results could be explained by the higher DOM leaching for A and D(F) compared to B, C(F), C(M) and D(M) increasing diuron-DOM interactions. These interactions seem to be related to the aromatic and aliphatic content of the DOM, determining formation of hydrogen and non-covalent bonds. The degree of organic matter maturity does not seem to have any effect with amendment C, while a reduction in diuron leaching is observed between D(F) and D(M). After equilibrium dialysis measurement of diuron-DOM complexes, it appeared that less than 3% of the diuron applied corresponded to complexes with a molecular weight >1000 Da. Complexes <1000 Da could also take part in this facilitated transport.
在勃艮第葡萄园下的一些饮用水水库中经常检测到敌草隆，这些地方会施用有机改良剂。这些改良剂对农药迁移的环境影响尚不明确：一方面，它可能通过增加土壤有机碳含量来增强农药的保留；另一方面，溶解有机物（DOM）可能促进农药的迁移。为了研究DOM与敌草隆的相互作用以及敌草隆和DOM可能的共同迁移，使用填充玻璃珠的柱子进行了淋溶实验。测试了四种有机改良剂（A、B、C和D）；C和D在新鲜（F）和成熟（M）阶段进行了采样。仅在A和D（F）改良剂中观察到敌草隆淋溶增加（与无DOM的空白样品相比，增加了16%），这表明DOM对敌草隆迁移有影响。这些结果可以解释为，与B、C（F）、C（M）和D（M）相比，A和D（F）的DOM淋溶更高，增加了敌草隆与DOM的相互作用。这些相互作用似乎与DOM的芳香族和脂肪族含量有关，决定了氢键和非共价键的形成。有机质成熟度似乎对改良剂C没有任何影响，而在D（F）和D（M）之间观察到敌草隆淋溶减少。在对敌草隆 - DOM复合物进行平衡透析测量后，发现施用的敌草隆中不到3%对应于分子量>1000 Da的复合物。分子量<1000 Da的复合物也可能参与这种促进迁移。
