External input to Lake Wadag - effective and estimate loadings

Comparison was made of effective and estimated loads of phosphorus and nitrogen coming from the catchment area to Lake Wadąg. It was concluded that the effective loads of phosphorus based on direct measurements were much similar to values obtained from the estimation method covering only diffused pollution sources. This seems to point out that external loads to lakes calculated as unit run-off of nutrients from dispersed, non-point (diffused) and point sources are too high (at least in the conditions of Pojezierze Olsztyńskie). Big discrepancies in run-off regarding effective nitrogen loads imply that the estimated values should be treated rather critically.