Phosphorus balance for soil and groundwater in the Netherlands, 1986-2002*
The supply of phosphorus to agricultural land fell by more than one third between 1986 and 2002. Approximately 85% of the total supply of phosphorus to the soil is to agricultural land, mainly in the form of manure and fertiliser.
| Supply | 1986 | 1990 | 2000 | 2001 | 2002* | |
| million kg P | ||||||
| Total agricultural land | 157 | 137 | 108 | 103 | 99 | |
| Manure | 113 | 95 | 74 | 74 | 70 | |
| Fertiliser | 36 | 33 | 27 | 23 | 23 | |
| Run-off and leaching | 5 | 6 | 4 | 3 | 3 | |
| Atmospheric deposition | 2 | 2 | 2 | 2 | 2 | |
| Other | 1 | 1 | 1 | 1 | 1 | |
| Total other land | 18 | 17 | 18 | 17 | 17 | |
| Local deposits | ||||||
| of which | sewage sludge | 2 | 3 | 1 | 1 | 1 |
| dredging sludge | 6 | 5 | 3 | 2 | 2 | |
| other waste | 7 | 6 | 5 | 5 | 5 | |
| Diffused supply | ||||||
| of which | atmospheric deposition | 1 | 1 | 1 | 1 | 1 |
| other | 3 | 2 | 8 | 8 | 8 | |
| Source: CBS. | CBS/EDC/Sep03/0196 | |||||
| Withdrawal | 1986 | 1990 | 2000 | 2001 | 2002* |
| million kg P | |||||
| Total agricultural land | 157 | 137 | 108 | 103 | 99 |
| Withdrawal in crops (incl. grass) | 65 | 62 | 58 | 55 | 61 |
| Leaching and run-off1) | 5 | 5 | 4 | 4 | 4 |
| Accumulation | 87 | 70 | 46 | 44 | 34 |
| Total other land | 18 | 17 | 18 | 17 | 17 |
| Run-off and leaching | 1 | 1 | 1 | 1 | 1 |
| Accumulation | 18 | 16 | 17 | 16 | 16 |
| Source: CBS. | CBS/EDC/Sep03/0196 | ||||
| 1) Using new calculation method from 2000 onwards. In time, the years in the history will be recalculated using a comparable method. As a result, the trend shift shown at present will be eliminated. | |||||
Developments in supply of phosphorus
The total supply of phosphorus to agricultural land decreased by over 35% between 1986 and 2002. This drop can be wholly attributed to the reduced supply of phosphorus in manure and fertiliser on agricultural land. Approximately 85% of the total supply of phosphorus to the soil is to agricultural land, mainly in the form of manure and fertilizer.
Developments in withdrawal of phosphorus
Of the total amount of phosphorus applied to agricultural land, approximately 35% accumulated in 2002 (this figure was approximately 50% in 1990 and approximately 55% in 1986).
Phosphorus not taken up by crops initially accumulates in the soil. However, soil has only a limited ability to accumulate (or stockpile) phosphorus. Eventually the soil becomes saturated with phosphorus and it runs off to ground and surface water. The total area of phosphate-saturated land is steadily increasing.
