38 status. Three classes are distinguished: low, neutral and high. The application use standard at a high rating of the soil P status is lower than the offtake by the crop. A neutral rating receives crops offtake and at a low rating the phosphate application standard is higher than crop offtake. Furthermore, a distinction is made between for grassland and arable land including field production of vegetables (see Table 5.3). For grassland and arable land the application of phosphate fertilisers has to be substantially decreased in the coming years to 2015. The objective of the quota is to reach a steady state fertilisation by 2015, which means that the amount of N and P fertilisers applied to the land match the amount of N and P extracted with the crops, plus an unavoidable loss of 5 kg P2O5 /ha (see VROM, 2004). It is assumed here that the steady-state fertilisation approach will not affect crop yield until at least 2030 (MNP, 2007). Gradually reducing the amount of phosphate that can be applied to the land does not necessarily imply that all farmers have to cut back on their current fertiliser application: some 35% of the agricultural soils in the Netherlands do not need phosphate fertilisation as a result of a high degree of phosphate saturation (see e.g. MNP, 2007). As such, the actual reduction of fertiliser consumption as a result of these legislative measures cannot be directly translated to effective reduction of agricultural phosphate consumption in general. The reduction measures also have a downside, as they lead to an excess of animal manure in some areas in the Netherlands. In 2006, the excess manure produced amounted to some 4 000 t P2O5, whereas in 2015 excess manure is estimated to amount to some 9 000 t P2O5 (Luesink et al., 2008). As such, a gradual reduction of livestock number – especially pigs – and poultry, should be considered in order to prevent an accumulation of excess manure, or manure should be digested more often and the phosphate recovered in mineral form. Table 5.3: Phosphate application standards for arable land and grassland during the period 2010-2015. The standards for 2014 and 2015 are indicative. The figures in brackets show the maximum quantity of phosphate from livestock than can be applied (Ministry of Agriculture, Nature and Food Safety, Fourth Action Programme Nitrate Directive (20102013). Third AP 2006 Grassland Soils with high phosphate levels 110 Phosphate-neutral soils 110 Soils with low levels of phosphate 110 2009 100 100 100 2010 90 95 100 Fourth AP 2011 90 95 100 2012 85 95 100 2013 85 95 100 Fifth AP 2014 85 95 100 2015 80 90 100 Arable land Soils with high phosphate levels 95 (85) 85 Phosphate-neutral soils 95 (85) 85 Soils with low levels of phosphate 95 (85) 85 75 80 85 70 75 85 65 70 85 55 65 85 55 65 80 50 60 75 Pagina 47

Pagina 49

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