Control of invasive aquatic plants is crucial for the maintenance of chemical, biological and ecological balances in many fresh water systems. Exposure of invasive plants to herbicides used for their control may be reduced by sorption to organic matter in sediments. Since granular herbicide formulations have closer contact with sediments (compared to liquid formulations), concentrations in the water column may be much lower. To test this hypothesis, microcosms containing sediments with < 1%, 6.4%, 19.7%, and 44% organic matter were treated with liquid and granular formulations of fluridone and penoxsulam. Herbicide concentrations in the water column and sediment pore water were monitored over 40 days. The presence of sediments (regardless of organic carbon content) significantly reduced concentrations of fluridone in the water column from the granular formulations relative to the liquid formulation. A similar, though less extreme, pattern was observed for penoxsulam in most of the organic carbon treatments.

控制入侵水生植物对于维持许多淡水系统的化学、生物和生态平衡至关重要。通过吸附到沉积物中的有机物质，可以减少入侵植物对用于控制它们的除草剂的暴露。由于颗粒状除草剂配方与沉积物的接触更紧密（与液体配方相比），水柱中的浓度可能要低得多。为了验证这一假设，用氟啶酮和五氟磺草胺的液体和颗粒制剂处理含有 < 1%、6.4%、19.7% 和 44% 有机物质的沉积物的缩影。对水柱和沉积物孔隙水中的除草剂浓度进行了 40 天的监测。相对于液体制剂，沉积物的存在（无论有机碳含量如何）显着降低了来自颗粒制剂的水柱中氟啶酮的浓度。在大多数有机碳处理中观察到五氟磺草胺的类似但不太极端的模式。