Agrichemical placement impacts on alachlor and nitrate movement through soil in a ridge tillage system

Alachlor, bromide, anhd calcium nitrate (¹⁵N labelled) were applied above 15 grid lysimeters to either the ridge top or valley area of a ridge tillage system. The grid lysimeters allowed temporal and spatial fractionation of leachate. Sixteen hours after agrichemical application, 15cm of water was applied with a rainfall simulator. Surface water flow increased the amount of water collected in lysimeters placed under valley areas when compared with ridge areas, which in turn increased the movement of N fertilizer, bromide, and alachlor through the soil profile. -from Authors