Keywords: Phosphorus, import, export, balance, pathway, EU.
Phosphorus (P), a major and essential nutrient for crops and animals, including humans. World resources of phosphate rock are finite, and at the present rate of use known reserves have a predicted lifespan of only about 200 years. There is therefore a pressing need to maximise the efficiency of use of this unsubstitutable nutrient, and to minimise avoidable losses. Losses occur in effluents to the sea, and to landfill. Phosphorus also has a role in freshwater eutrophication in Europe. It is important therefore that flows of phosphorus into and out of the EU, and pathways within the EU, are understood and, so far as is practicable, quantified. This was the aim of a study funded by EFMA, results of which are summarised here. The base year for the study was 2006 and geographical area was EU27. Data on material imports and exports, fisheries and population change were available from Eurostat databases. Livestock numbers were taken from Eurostat and, where necessary, FAO and national databases. Published data from EEA and elsewhere were available for phosphorus losses to sea and for deposition from the atmosphere. A wide variety of published sources was used for the phosphorus concentrations in different materials. Phosphorus movements in traded materials, dominated by those in fertilisers, rock phosphates and phosphoric acid, resulted in an estimated net import of 1.8 million tonnes P. Of this, some 0.6 million tonnes P was estimated to have been locked up in durable structures. Transfers of phosphorus into and out of soil were considerable. It was estimated that 2.2 million tonnes P was removed from soil in harvested crops and livestock. Around 2.1 million and 1.3 million tonnes P were returned to soil in livestock manures and fertilisers respectively. After taking account of inputs from other wastes and from deposition, the estimated average net balance for agricultural soil in the EU27 was 8 kg P/ha.
I R Richards, Ecopt, Ufford Road, Bredfield, Suffolk IP13 6AR, UK. C J Dawson, Westover, Ox Carr Lane, Strensall, York YO32 5TD, UK.
29 pages, 1 figure, 10 tables, 39 references.
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