Fertilizer Applications and Soil P Status in Western Europe

In order to assess the trends of phosphate fertilizers use in West European countries, a survey was launched in 1989 through a questionnaire sent to research and extension organizations in several countries including Belgium, Denmark, Finland, Germany, Ireland, Switzerland, the Netherlands and the United Kingdom.

The results from the survey showed large differences in phosphate fertilizer recommendations, which could not be fully explained by soil scientists, and a decline in phosphorus use on some crops. New agro-environmental regulations and cash-flow problems facing farmers were largely responsible for the decline.

Fertilizer recommendations varied according to the general P application status of the region (deficient or high P input), and crop requirements. In the loamy cereal zones of Belgium, withholding P fertilization was rarely recommended despite the high P status of soils. In the West and North parts of Denmark, in Finland, the North of Germany and Belgium, and The Netherlands, the policy is to limit the application of P fertilizers due to the positive P balances observed. In the United Kingdom and Ireland, traditional fertilization was pursued and the possible detrimental effect on soil and water quality was not raised as a very important issue.

The soil P status in the countries under review varied firstly with the soil types and agro-ecological conditions, secondly with the management of phosphate fertilization at the farm level and finally with the macro-economic contingencies.

It was found that at least ten different extraction methods are used in the countries covered in the survey. Historical circumstances and geographical conditions are responsible for this rather large variety of methods used in routine analysis to assess plant available soil phosphorus. Consequently, the norms of phosphate fertility levels used for soil classification (deficient, adequate, or excessive) cannot be compared among countries, sometimes not even within the same country. This creates a difficulty in generalizing results or observations obtained from one country to the rest of Europe.