Canadian Forest Service Publications
Urea fertilization of natural forest : effects on water quality. 1978. Gonzalez, A.; Plamondon, A.P. For. Ecol. Manage. 1(3): 213-221.
Issued by: Laurentian Forestry Centre
Catalog ID: 16348
Availability: PDF (request by e-mail)
Urea at the rate of 150 kg N/ha was applied by helicopter to a 120 ha watershed covered with a natural stand of balsam fir (Abies balsamea Mill.), white spruce (Picea glauca Moench.) and paper birch (Betula papyrifera Marsh.), 80 km from Quebec City. Two-thirds of the area was treated in June, and the remainder in September, the control area was an adjacent comparable watershed. Abundant rainfall coincided with the application. In stream water, urea was identified only at trace levels during the 48 hours following fertilization. Ammonium concentrations and conductivity increased significantly during the 10-15 days following application. Small changes were observed concerning other parameters studied. Urea fertilization did not considerably alter water quality.