El Imache Ahde, Dahchour Abdelmalek, Elamrani Btissam, Dousset Sylvie, Pozzonni Fironzo, Guzzella Lucia
Faculté des Sciences-Ain Chock, Université Hassan II, Maarif Casablanca, Morocco.
J Environ Sci Health B. 2009 Jan;44(1):31-7. doi: 10.1080/03601230802519579.
The increasing use of pesticides in Morocco raises the potential risk of groundwater contamination, notably in the Gharb area, which has a shallow groundwater table. Thus, the leaching of two phenyl-ureas, diuron and linuron and their metabolites through undisturbed soil columns was studied under outdoor conditions. The soil chosen is a loamy clay soil, representative of the Gharb agricultural area. After four irrigation events were applied from 31/03/2005 to 15/05/2005, leachates contained higher amounts of linuron (from 0.08% to 6.96% of applied linuron) than diuron (from 0% to 0.27%). The greater mobility of linuron might be related to its higher water solubility (64 mg x L(- 1) compared with 42 mg x L(- 1) for diuron) and smaller adsorption coefficient (K(oc) of 400 L x kg(- 1), compared with 480 L x kg(- 1) for diuron). Concerning their metabolites, greater amounts of, N'-(3,4-dichlorophenyl)-N, (DCPMU) than N'-3,4-dichlorophenylurea (DCPU) were detected N-dimethylurea in the percolates, from 0% to 0.046% and from 0% to 0.008%, respectively. At the end of the monitoring period, more linuron residues than diuron residues were recovered in the soil profiles, 25.02% and 16.41%, respectively. The diuron residues were found mainly in the 0-20 cm soil layer, whereas linuron residues reached the 20-40 cm soil layer. Under such experimental conditions, linuron leaching, and thus its potential to contaminate groundwater, is greater than that of diuron.
摩洛哥农药使用量的增加提高了地下水污染的潜在风险，尤其是在地下水位较浅的加尔卜地区。因此，研究了在室外条件下，两种苯基脲类除草剂（敌草隆和利谷隆）及其代谢物通过原状土柱的淋溶情况。所选土壤为壤质粘土，代表加尔卜农业区。在2005年3月31日至2005年5月15日进行了四次灌溉后，渗滤液中利谷隆的含量（占施用利谷隆的0.08%至6.96%）高于敌草隆（占0%至0.27%）。利谷隆更强的迁移性可能与其更高的水溶性（64mg/L，而敌草隆为42mg/L）和更小的吸附系数（有机碳吸附系数K(oc)为400L/kg，而敌草隆为480L/kg）有关。关于它们的代谢物，渗滤液中检测到的N'-(3,4-二氯苯基)-N,N-二甲基脲（DCPMU）比N'-3,4-二氯苯基脲（DCPU）更多，分别为0%至0.046%和0%至0.008%。在监测期结束时，土壤剖面中回收的利谷隆残留量比敌草隆残留量更多，分别为25.02%和16.41%。敌草隆残留主要存在于0-20cm土层，而利谷隆残留则到达了20-40cm土层。在这种实验条件下，利谷隆的淋溶及其污染地下水的可能性大于敌草隆。
