MODELS FOR PREDICTING SOIL ZINC AVAILABILITY FOR BARLEY

Regression models are proposed for the prediction of soil zinc availab ility within different pH ranges. The relationship between zinc concen tration in barley plants, zinc content in soils and soil pH was descri bed using a two-dimensional diagram. Results show that the soil zinc a vailability is significantly affected by pH changes at pH above 6.5. B elow this point, the pH effect becomes gradually less important. In th e low pH range, the soil zinc availability is mainly dependent on soil zinc quantity.