Skerratt Jennifer, Baird Mark E, Mongin Mathieu, Ellis Robin, Smith Rachael A, Shaw Melanie, Steven Andy D L
CSIRO Environment, Hobart 7001, Australia.
CSIRO Environment, Hobart 7001, Australia.
Sci Total Environ. 2023 Jun 25;879:163041. doi: 10.1016/j.scitotenv.2023.163041. Epub 2023 Mar 24.
Pesticides from urban and agricultural runoff have been detected at concentrations above current water quality guidelines in the Great Barrier Reef (GBR) marine environment. We quantify the load of the pesticide diuron entering GBR waters using the GBR-Dynamic SedNet catchment model. After comparison of simulated distributions with observations at 11 monitoring sites we determined a half-life of diuron in GBR marine waters of 40 days. We followed diuron dispersal in the GBR (2016-2018) using the 1 km resolution eReefs marine model. The highest diuron concentrations in GBR waters occurred in the Mackay-Whitsunday region with a spike in January and March 2017, associated with 126 and 118 kg d diuron loads from Plane Creek and the O'Connell River respectively. We quantify areas of GBR waters exposed to potentially ecotoxic concentrations of diuron. Between 2016 and 2018, 400 km and 1400 km of the GBR were exposed to concentrations exceeding ecosystem threshold values of 0.43 and 0.075 μg L respectively. Using observed mapped coral and seagrass habitat, 175 km of seagrass beds and 50 km of coral habitats had peak diuron concentrations above 0.075 μg L during this period. While the highest concentrations are localised to river plumes and inshore environments, non-zero diuron concentrations extend along the Queensland coast. These simulations provide new knowledge for the understanding of pesticide dispersal and management-use in GBR catchments and the design of in-water monitoring systems.
在大堡礁（GBR）海洋环境中，已检测到来自城市和农业径流的农药浓度超过了当前的水质标准。我们使用GBR - Dynamic SedNet流域模型来量化除草剂敌草隆进入大堡礁水域的负荷。在将模拟分布与11个监测点的观测结果进行比较后，我们确定了敌草隆在大堡礁海水中的半衰期为40天。我们使用1公里分辨率的eReefs海洋模型跟踪了2016 - 2018年期间大堡礁中敌草隆的扩散情况。大堡礁水域中敌草隆的最高浓度出现在麦凯 - 圣灵群岛地区，在2017年1月和3月出现峰值，分别与来自普莱恩河和奥康奈尔河的126千克/天和118千克/天的敌草隆负荷有关。我们量化了大堡礁水域中暴露于可能具有生态毒性浓度敌草隆的区域。在2016年至2018年期间，大堡礁分别有400公里和1400公里的区域暴露于超过生态系统阈值0.43微克/升和0.075微克/升的浓度之下。利用观测绘制的珊瑚和海草栖息地地图，在此期间，175公里的海草床和50公里的珊瑚栖息地的敌草隆峰值浓度超过了0.075微克/升。虽然最高浓度集中在河口羽状流和近岸环境中，但非零浓度的敌草隆沿着昆士兰海岸延伸。这些模拟为理解大堡礁集水区农药扩散和管理应用以及水中监测系统的设计提供了新知识。
