Farm-Scape is sponsored by Manitoba Pork Council and Sask Pork Play Audio Farm-Scape is a Wonderworks Canada production and is distributed courtesy of Manitoba Pork Council and Sask Pork.

Farm-Scape, Episode 1553

A University of Saskatchewan study has shown repeated use of liquid swine manure to fertilize crops has no negative impact on soil metals content or the metals content of plants growing on the soil.

A graduate student study, conducted as part of the University of Saskatchewan's long term effort to evaluate the effects of repeated application of swine manure, zeroed in on soils metals content and metals content of plants growing on the soil.

Senior Researcher Dr. Jeff Schoenau says, while the study focused on copper and zinc, it also looked at heavy metals considered a concern for human health.

"What that study found in general is that the main impact of repeated applications of manure on soil metals was that it did produce some small increases in the micronutrients copper and zinc both in available portions, total portions in the soil and also increased the content of these micronutrients in plant material.

That's not surprising as copper and zinc are added, as supplements, to swine diets and subsequently those elements are plant micronutrients that are taken up by the plant.

In terms of other metals that we looked at like cadmium and selenium, we found that applications of liquid swine manure had no impact on the total amounts of those in the soil nor really did it have any impact on the accumulation of those metals in the plants."

Dr. Schoenau points out copper and zinc are micronutrients required by plants and are not of concern. He says where increases of those elements were detected in the soil they were small and would be offset by plant removal.

He says elements that would be of concern, like cadmium, are not present in manure so it was no surprise that manure use had no impact on the level of those metals in the soil.

For Farmscape.Ca, I'm Bruce Cochrane.