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The procedure for applying phosphorus (P) fertilizer to soil can be divided into three consecutive steps: (i) Measurement of soil‐P availability, (ii) calibration of the soil‐P fertility level and (iii) estimation of the recommended P dose. Information on each of these steps was obtained for 18 European countries and regions with the aim of comparing P fertilizer recommendation systems at the European scale. We collected information on P fertilizer recommendations through conventional or grey literature, and personal contacts with researchers, laboratories and advisory services. We found much variation between countries for each of the three steps: There are more than 10 soil‐P tests currently in use, apparent contradictions in the interpretation of soil‐P test values and more than 3‐fold differences in the P fertilizer recommendations for similar soil‐crop situations. This last result was confirmed by conducting a simple experimental inter‐laboratory comparison. Moreover, soil properties (pH, clay content) and crop species characteristics (P responsiveness) are used in some countries in the calibration and recommendation steps, but in different ways. However, there are also common characteristics: soil‐P availability is determined in all countries by extraction with chemical reagents and the calibration of the soil‐P test values, and the fertilizer recommendations are based on the results from empirical field trials. Moreover, the fertilizer recommendations are nearly all based on the amount of P exported in the crops. As long as rational scientific and theoretical backgrounds are lacking, there is no point in trying to synchronize the different chemical methods used. We therefore call for a mechanistic approach in which the processes involved in plant P nutrition are truly reproduced by a single standard method or simulated by sorption‐desorption models.

Erosion and loss of organic carbon (OC) result in degradation of the soil surface. Rill and interrill erosion processes on a silt loam soil were examined in laboratory rainfall and flume experiments. These experiments showed that rill and interrill erosion processes have contrasting impacts on enrichment of OC in transported sediment. Rill erosion was found to be nonselective, while for interrill erosion the enrichment ratio of OC, EROC, varied between 0.9 and 2.6 and was inversely related to the unit sediment discharge. At unit sediment discharge values >0.0017 kg s−1 m−1, the EROC remained equal to 1. The enrichment process was not influenced by raindrop impact. Enrichment of OC by “aggregate stripping” was found to be unimportant in our study. This was attributed to the low aggregate stability of the soil and the equal distribution of OC within the different soil aggregate classes.

Data from the Farm Accountancy Data Network revealed that from 1989 to 2001 the average farm-gate N surplus of Flemish specialized dairy farms decreased from 378 to 238 kg N ha À1, the corresponding whole-farm N efficiency increased from 15% to 22%. Study of European literature on dairy farming, of experimental farms or farm groups and of progressive Flemish farms showed that there is scope for further improvement of the N use efficiency in Flemish dairy farming. The improvement can mainly be realized by changes in the operational management, resulting in an ever decreasing use of fertilizer N and concentrate N. Reasonable targets for sustainable dairy farming in Flanders are 150 kg N ha À1 year À1 for the farm-gate N surplus and about 85 kg milk kg À1 N surplus for eco-efficiency. These targets can be reached at production levels of up to 10,000 à 12,000 l ha À1 and at a satisfying income per unit of labour.

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