Total Phosphorus

The model for total phosphorus was based on sediment reduction. Although total phosphorus is composed of both soluble and particulate forms, particulate forms represent the bulk of phosphorus lost from conventionally cultivated fields. The total phosphorus model was developed from 63 observations; more data than any other nutrient model. The intercept was not significant. Sediment reduction was able to explain 43% of the variability. The model was applied to all particulate forms of phosphorus in the SWAT+ VFS submodel. The model is given below:

$TP_R=0.90 S_R$ 6:5.1.5

where $TP_R$ is the total phosphorus reduction (%); and $S_R$ is the sediment reduction (%).