Tile Drainage Flow Partitioning and Phosphorus Export in Vermont USA

Tile drainage (TD) has been identified as a potential non-point source of phosphorus (P) pollution and subsequent water quality issues. Three fields with TD in Vermont USA were monitored to characterize hydrology P export. Fields corn silage used minimal tillage cover cropping practices. Preferential flow path (PFP) activity was explored by separating into pathway connectivity components using two hydrograph separation techniques, electrical conductivity end member unmixing, recession analysis. the dominant export because higher total discharge. Drought conditions during this study limited surface runoff, possibly resulted maximum PFP active clay soils. The non-growing season dominated annual loading for three years. Peak concentrations occurred events following manure injection fall, well spring post crop termination post-planting. Intra-event analysis rainfall pulses showed that intensity pulses. This highlights impacts current management, climate change increase transport TD.