Assessing nutrient availability variations in landscapes
Qian, P., J.J. Schoenau, L.E. Cowell and L. Dennis. 1994. In Soils and Crops Workshop Proc., pp. 274-279. Univ. Saskatchewan
Abstract
A simple method was developed to assess the variability in nutrient availability in undulating landscapes using anion exchange resin strip burial. Resin strips were buried in ten farm fields along transects at points in the landscape representing different landform elements present within the field. In all ten fields, strips were buried for one hour. In two of the fields, in addition to a one hour burial, another set of resin strips was buried and allowed to remain in the soil for two weeks. After burial, resin strips were removed and the nitrate accumulated on the strips was measured. Large variations in nutrient availability as predicted by resin strip burial were observed in the landscapes. The differences were closely related to the landscape position and landform element with the highest levels of available nitrate observed at lower slope positions where deposition of eroded soil has occurred. Two week burials revealed that mineralization contributes significantly to available nitrate in the soil. Resin strip burial appears to be a suitable tool for evaluating variations in nutrient availability in different landscape positions of a field.
Key Words
landscape variability, nutrient availability, ion exchange resin, residual NO3-N, N mineralization
