Provincial monitoring of nitrates in 10 P.E.I. rivers shows levels are rising, according to a recently released report.
In three of the streams — the Wilmot, Dunk and Clyde — nitrate levels were over the Canadian Water Quality Guideline for Aquatic Life. The source of the nitrates is mostly agricultural fertilizer, the provincial report says.
Environment Minister Steven Myers said recent droughts are the expected culprit. Without timely rain plants can’t absorb the fertilizer, and then it washes into streams.
“While that’s an easy excuse I think we know that we need to tackle nitrates at a higher level and we need to find a way to reduce nitrates,” said Myers.
“That’s exactly what we’re going to try to do.”
Trees, biochar, precision agriculture may help
Myers said a current research project is showing promise — a partnership among farmers, environmental groups and Dalhousie University that plants willow trees around farms to absorb excess nutrients.
The province is also looking at using biochar, an engineered charcoal made from non-wood organic substances such as compost. Biochar spread on fields can reduce nitrate leaching by improving moisture retention.
Improvements in precision agriculture, which applies fertilizer more exactly when and where it is needed, could also help, said Myers.
Irrigation is an integral part of precision agriculture, he said, and that’s one reason why the province is lifting the moratorium on high-capacity wells for agriculture.