TY - JOUR T1 - The effect of vegetation on pesticide dissipation from ponded treatment wetlands: Quantification using a simple model JF - Chemosphere Y1 - 2008 A1 - Michael T. Rose A1 - Angus N. Crossan A1 - Ivan R. Kennedy KW - Cotton KW - Herbicide KW - Insecticide KW - Macrophyte KW - Phytoremediation KW - Runoff water AB -

Field data shows that plants accelerate pesticide dissipation from aquatic systems by increasing sedimentation, biofilm contact and photolysis. In this study, a graphical model was constructed and calibrated with site-specific and supplementary data to describe the loss of two pesticides, endosulfan and fluometuron, from a vegetated and a non-vegetated pond. In the model, the major processes responsible for endosulfan dissipation were alkaline hydrolysis and sedimentation, with the former process being reduced by vegetation and the latter enhanced. Fluometuron dissipation resulted primarily from biofilm reaction and photolysis, both of which were increased by vegetation. Here, greater photolysis under vegetation arose from faster sedimentation and increased light penetration, despite shading. Management options for employing constructed wetlands to polish pesticide-contaminated agricultural runoff are discussed. The lack of easily fulfilled sub-models and data describing the effect of aquatic vegetation on water chemistry and sedimentation is also highlighted.

VL - 72 UR - http://dx.doi.org/10.1016/j.chemosphere.2008.04.059 IS - 7 ER -