Pesticides used for intensive agricultural production threaten the water resources of the French West Indies. For example, the pesticide chlordecone was used until the nineties in banana fields. Operational and simple tools are needed to assess the potential risk of pollution by pesticides. Here, we propose a method to assess the spatial variability of pollution risk on a watershed scale. This method proceeds in four steps: (1) surveying practices; (2) determining the pesticide load for each field in the watershed; (3) establishing an indicator of pollution contribution for each field based on the load of pesticide per year weighted by the toxicity and solubility of each molecule; and (4) spatializing the indicator. We applied this method to an agricultural watershed in the north of Martinique, French West Indies. The results showed detailed information of pesticide dose spread and the distribution of the pollution risk, highlighting risk areas. Specifically designed for the volcanic and tropical areas of the French West Indies, our method could be adapted by integrating other data on soil-climate conditions and the topography.

中文翻译：

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评估农药污染风险：从田间到流域

用于集约化农业生产的农药威胁着法属西印度群岛的水资源。例如，农药十氯酮在香蕉田中一直使用到九十年代。需要操作和简单的工具来评估农药污染的潜在风险。在这里，我们提出了一种在分水岭规模上评估污染风险的空间变异性的方法。该方法分四个步骤进行：（1）测量实践；（2）确定流域每个田地的农药负荷量；（3）根据每年的农药负荷量，各分子的毒性和溶解度加权确定各领域的污染贡献指标；（4）空间化指标。我们将此方法应用于法属西印度群岛马提尼克岛北部的农业流域。结果显示了农药剂量分布的详细信息和污染风险的分布，突出了风险领域。我们的方法专为法属西印度群岛的火山和热带地区而设计，可以通过整合有关土壤气候条件和地形的其他数据进行调整。