| In the Missisquoi Bay of Lake Champlain situated in the South of Quebec, phosphorus originating from agricultural sources has been found to be a major contributor to the deterioration of water quality. This study sought to evaluate the nutrient loads, most particularly phosphorus, exported through surface runoff and tile drainage from two agricultural fields of the Missisquoi Bay watershed. As part of the study, a phosphorus simulation model was tested on one agricultural field. The evaluation of FHANTM 2.0 assessed the model's capacity to simulate the transport of phosphorus on agricultural fields.;FHANTM's simulation of hydrology for one field gave slightly negative coefficients of performance (CP), representing a poor capacity to simulate surface and subsurface runoff depths. The simulation of phosphorus concentrations in surface runoff showed a small range of values compared to field measurements, while simulations of phosphorus concentration in tile drainage were considered acceptable. Therefore, the overall evaluation of the FHANTM 2.0 model indicated that it had difficulty in simulating the transport of phosphorus from an agricultural field in Quebec.;From the two experimental fields studied, the results showed that the mean phosphorus load exported was larger in surface runoff than in tile drainage. The mean phosphorus load exported was 1.21 kg ha-1yr -1 in surface runoff, and 0.61 kg ha-1yr-1 in tile drainage. In contrast, nitrate loads exiting the fields were larger in tile drainage than in surface runoff. Over the two year study, the mean nitrate load was 5.64 kg ha-1yr-1 in surface runoff, and 91.43 kg ha-1yr-1 in tile drainage. |
