This paper summarizes the results of recent studies concerning the agricultural nutrient load to surface waters in Finland and possible management practices for reducing nutrient losses from agricultural land. Both the nitrogen and the phosphorus load exceed the loads from municipal and industrial sources together, thus being mainly responsible for the eutrophication of surface and coastal waters. 25% of the total agricultural phosphorus load is bioavailable dissolved reactive phosphorus, and 5% of the paniculate phosphorus load is available for algae. Reduced tillage, filter strips and permanent grassland on the set-aside land are means investigated for reducing erosion and nutrient losses. Based on experiments and model simulations, it is estimated that a wide adoption of all these practices would reduce total phosphorus load by about 40%. Soluble phosphorus and nitrogen losses can be reduced by adjusting the amount and timing of fertilization and manure application to the actual needs of plants. If the whole set-aside area was under permanent grassland, the nitrogen loss would decrease by about 17%, but the effect of cover or undersown crops in Finnish conditions is still unknown. More investigations are also needed of the effects of all these management practices on the soluble phosphorus load.

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