Edafología. Volumen 7-2. Mayo 2000. pag 113-124.
In a conventional olive plantation (100 trees/ha), located in a semiarid area (Almatret-Lleida) a fertiliser trial was done using three dose pig slurry in front of a mineral nitrogen fertiliser along 3 years (1997-99). Deviations in the nutrient contents of the pig slurry used in the trial in relation with average in the nutrient contents published from other studies made in the area are responsible for large increases in the amount of nutrients (N,P,K) applied over fertilisation of the olive crop does not increase yields and in 1999 a decrease was found for the higher pig slurry application dose. The positive balance between applied and exported nutrient has produced a large increase in the nitrate content in the soil at depths larger than 90 cm and also an increase in the electrical conductivity, organic mater, total nitrogen, phosphorus and potassium. The foliar analysis shows are increase in the contents of N for the higher dose.
From the results obtained it comes out that the dose applied should be lower than the trialed, using a larger number of fields if needed. An option which seems possible in to apply such fertiliser in alternate years taking in account the pedoclimatic characteristics of the area.