Assessing the effect of soil testing on chemical fertilizer use intensity: An empirical analysis of phosphorus fertilizer demand by Irish dairy farmers

Abstract

Phosphorus (P) is considered the second most important nutrient for grass growth following nitrogen (N) and it is applied on grasslands mainly through chemical fertilizers. Irrational use of chemical fertilizers, however, lead to severe and often irreversible environmental degradation, which has, consecutively, an impact on the overall sustainability of the world. Farmers are responsible for the amount of P fertilization on their farm, and despite the efforts to design policies to assist them with precise chemical fertilizer use, chemical P use is still high, particularly on pasture fields where grass needs to be constantly maintained. . In Ireland, where agriculture is majorly pasture based, soil testing is highly recommended, as part of the Irish rural development plans, in order to encourage efficient nutrient management. This study uses an econometric model on data from the Irish national farm survey to examine the examines the relation between soil testing and chemical P fertilization in Irish pasture based farm systems. Results indicate the soil-testing leads to the use lower amounts of chemical fertilizers, which is also correlated with landscape characteristics and farm intensity, indicating the need for targeted management approaches to farm level management decision making.