Economic Impact of Nutrient Losses from Wind Erosion of Cereal Soils in Southeast Spain.

Abstract

The influence of wind erosion on soil productivity was studied applying fan-forced wind in a wind tunnel located in the Campo de Nijar area in SE Spain where the main crops are cereals. Wind erosion is highly variable depending on the type of soil (aric-haplic Calcisols, aric-calcaric Cambisols or aric-calcic Luvisols, according to IUSS Working Group WRB, 2014) and the time elapsed since the last tillage. This is because of the formation of a physical crust after tillage, which protects the soil from wind. Crusting in our area is favored by the strong effect of dew, which makes crust form in from eight to ten days. Nutrient losses from wind involve an additional cost in fertilization for a crop to be economically viable. The repeated measures ANOVA shows that very fine sand and coarse silt are the fractions most susceptible to loss due to the effect of wind. The same statistical analysis shows that the smallest differences in fertility appear in OC and K2O, increasing in N and P2O5. Based on experimental data, we calculated the approximate cost of restoring organic matter, N, P2O5 and K2O losses to the soil proportional to wind erosion, on the base of mineral fertilizers usually employed and average prices. This does not include the contribution to maintaining short and long-term productivity and soil fertility required for growing, or natural contributions from wind deposits and runoff.