reserves) and reserve base (including the marginally and sub-economic reserves) is estimated. Although particularly the role of biofuel production is difficult to assess here, it seems likely that the current reserves will be exhausted somewhere between 2040 and 2070, and the reserve base somewhere between 2100 and 2150. These estimates are in line with previous projections, but the size of the reserve and reserve base are based on rock phosphate prices of 20 – 40 US$/t. At prices of 50 - 100 US$/t the future reserve base would roughly double and phosphate sufficiency will last well into the next few centuries. Chapter 5: Phosphate in the Netherlands Net phosphate consumption in the Netherlands currently amounts to some 183 000 t P2O5 (~ 11 kg P2O5/capita), most of which is in organic matter (animal feed - 59%). The role of inorganic phosphate such as fertilisers and feed additives is less important (35%). This shows that the consumption of inorganic phosphate through mineral fertilisers does not necessarily represent total phosphate consumption, particularly for countries that are dependent to a substantial degree on the import of animal feed for their livestock such as the Netherlands, Belgium and Denmark. Since the early nineteen-eighties, the total consumption of phosphate in the Netherlands has decreased by around 47%. This decrease was caused by lower consumption levels of animal feed (addition of phytase) and decreasing consumption of inorganic phosphate fertilisers as well as other forms of phosphate (e.g. detergents). Recent new Dutch legislation regarding nutrient application on agricultural land, in which maximum allowed levels of nutrients are gradually decreased towards 2015, expects a further decrease in agricultural phosphate consumption. Due to historical over-application of mineral fertilisers and manure, a substantial amount of phosphate has accumulated in agricultural soils in the Netherlands; on average the concentrations of P2O5 have tripled and a substantial fraction of the soils is phosphate saturated. It is estimated that the current accumulated phosphate fraction in the agricultural topsoils amounts to some 1.9 Mt of P2O5, which is ~40 years of current fertiliser application. Part of this fraction will gradually become available for plants, and offers opportunities for reducing phosphate application without significant loss of crop yield. Chapter 6: Phosphate recycling and recommendations for sustainable use The increasing consumption and subsequent future scarcity of phosphate resources, are ample reasons for the transition to a more sustainable use of phosphate: Geological/Geo-political: the Netherlands is fully dependent on the import of phosphate from abroad, and worldwide resources of phosphate are limited.\ Economic: future phosphate prices are likely to remain high at 50 – 100 US$/ton, increasing fertiliser costs and subsequently animal feed prices. 3 Pagina 12

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