University of Toulouse; INP, UPS; Laboratoire d'Ecologie Fonctionnelle et Environnement (EcoLab); ENSAT, Avenue de l'Agrobiopole, 31326 Castanet Tolosan Cedex, France.
J Hazard Mater. 2011 Nov 30;196:210-9. doi: 10.1016/j.jhazmat.2011.09.012. Epub 2011 Sep 10.
Rising pesticide levels in streams draining intensively managed agricultural land have a detrimental effect on aquatic ecosystems and render water unfit for human consumption. The Soil and Water Assessment Tool (SWAT) was applied to simulate daily pesticide transfer at the outlet from an agriculturally intensive catchment of 1110 km(2) (Save river, south-western France). SWAT reliably simulated both dissolved and sorbed metolachlor and trifluralin loads and concentrations at the catchment outlet from 1998 to 2009. On average, 17 kg of metolachlor and 1 kg of trifluralin were exported at outlet each year, with annual rainfall variations considered. Surface runoff was identified as the preferred pathway for pesticide transfer, related to the good correlation between suspended sediment exportation and pesticide, in both soluble and sorbed phases. Pesticide exportation rates at catchment outlet were less than 0.1% of the applied amount. At outlet, SWAT hindcasted that (i) 61% of metolachlor and 52% of trifluralin were exported during high flows and (ii) metolachlor and trifluralin concentrations exceeded European drinking water standards of 0.1 μg L(-1) for individual pesticides during 149 (3.6%) and 17 (0.4%) days of the 1998-2009 period respectively. SWAT was shown to be a promising tool for assessing large catchment river network pesticide contamination in the event of floods but further useful developments of pesticide transfers and partition coefficient processes would need to be investigated.
从密集管理的农业土地中流出的溪流中，上升的农药水平对水生生态系统产生了有害影响，使水不适合人类饮用。土壤和水评估工具（SWAT）被应用于模拟 1110 平方公里（2）（法国西南部的 Save 河）农业密集流域出口处的农药日转移。SWAT 可靠地模拟了 1998 年至 2009 年期间溶解和吸附的甲草胺和氟乐灵的负荷和浓度。每年，考虑到年降雨量的变化，在出口处平均有 17 公斤甲草胺和 1 公斤氟乐灵被输出。地表径流被确定为农药转移的首选途径，这与悬浮泥沙输出与可溶性和吸附相农药之间的良好相关性有关。在出口处，SWAT 预测到出口处出口的农药（i）61%的甲草胺和 52%的氟乐灵是在高流量期间输出的，（ii）在 1998 年至 2009 年期间，有 149 天（3.6%）和 17 天（0.4%）的时间，甲草胺和氟乐灵的浓度超过了欧洲饮用水标准 0.1 μg L（-1）。SWAT 被证明是评估洪水期间大流域河网农药污染的一种很有前途的工具，但需要进一步研究农药转移和分配系数过程的有益发展。
