Mobilization of pesticides on an agricultural landscape flooded by a torrential storm
Mobilization of pesticides on an agricultural landscape flooded by a torrential storm
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DOI：
10.1897/03-668.1
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发表时间：
2005-01-01
影响因子：
4.1
通讯作者：
Syrgiannis, J
中科院分区：
文献类型：
--
作者：
Donald, DB;Hunter, FG;Syrgiannis, J
在极端降水事件之后，农药被调动到被淹没的农业景观的地表沃茨中，这在以前还没有被调查过。2000年7月3日，加拿大萨斯喀彻温省东南部的Vanguard地区在经历了45 d的96 mm降雨后，又遭遇了一场8 h内降雨量高达375 mm的特大暴雨。大多数除草剂，但没有杀虫剂，将在风暴前四周内应用于先锋地区的作物。风暴过后，在被淹没的湿地中检测到19种除草剂和杀虫剂，其中14种在50%或更多的湿地中检测到。平均浓度范围从0.43纳克/升（硫丹）到362纳克/升（2，4-二氯苯氧乙酸）不等。这些杀虫剂可能来自远距离迁移，然后在雨水中沉积，以及来自对遭受风暴的地区（1，700 km（2））内的作物施用的除草剂。在接下来的一年里，当同样的45天里只有62毫米的降雨量时，只有五种农药在50%或更多的湿地中被检测到。我们估计，在1，700 km（2）的风暴带中，278 kg除草剂进入雨水并通过径流进入地表沃茨，105 kg除草剂通过排入Notukeu Creek从Vanguard地区排出。当大草原农业景观遭受暴雨时，大量的除草剂被动员到水生环境中。在这种情况下。被水淹没的威尔斯井和用作饮用水源的小型城市水库可能受到10种或更多种杀虫剂的危害，其中一些杀虫剂的浓度相对较高。
Mobilization of pesticides into surface waters of flooded agricultural landscapes following extreme precipitation events has not been previously investigated. After receiving 96 mm of rain in the previous 45 d, the Vanguard area of southeastern Saskatchewan, Canada, was subjected to a torrential storm on July 3, 2000, that produced as much as 375 mm of rain in 8 h. The majority of herbicides, but no insecticides, would have been applied to crops in the Vanguard area during the four weeks preceding the storm. After the storm, 19 herbicides and insecticides were detected in flooded wetlands, with 14 of them detected in 50% or more of wetlands. Average concentrations ranged from 0.43 ng/L (endosulfan) to 362 ng/L (2,4-dichlorophenoxyacedic acid). The pesticides probably were from long-range transport, followed by deposition in rain, and from herbicides applied to crops within the area subjected to the storm (1,700 km(2)). In the following year, when only 62 mm of rain fell in the same 45 d, only five pesticides were detected in 50% or more of wetlands. We estimated that for the 1,700-km(2) storm zone, 278 kg of herbicide were mobilized into rain and by runoff into surface waters, and 105 kg were removed from the Vanguard area by discharge into Notukeu Creek. Significant quantities of herbicides are mobilized to aquatic environments when prairie agricultural landscapes are subjected to torrential storms. In these circumstances. flooded wells and small municipal reservoirs used as sources of drinking water may be compromised by 10 or more pesticides, some at relatively high concentrations.