Browsing by Author "Suono, Anu"

The aim of this study was to discover whether amending the soils with gypsum is a viable measure to decrease phosphorus runoff from the Archipelago Sea catchment and how the measure would contribute to the phosphorus reduction targets set by the Baltic Sea Action Plan and the Finnish marine strategy. This was done by calculating the runoff reduction potential and costs for gypsum and comparing these to an existing measure in the agri-environmental scheme, establishment of buffer zones. The results in this study indicate that gypsum would be a reasonable way to decrease phosphorus loading to the Archipelago Sea. An annual reduction of 68 tons would be possible with gypsum, with a total cost of 6.4 million euros – or 94 euros per reduced kilogramme. To achieve the same reduction amount with buffer zones, it would require nearly 11% share of buffer zones in the cultivated area, which would cost 7.5 million or 111 euros per kilogramme of reduced phosphorus. The reduction target set for the Archipelago Sea in the Finnish marine strategy is 100 tons of phosphorus, and 68% of this target may reached with gypsum. However, gypsum does not reduce soil phosphorus and thus is not a long-term solution for reducing phosphorus runoff. It would be a good measure to use in interim, while soil phosphorus levels are lowered through reduced fertilizer application rates, especially since it does not reduce cultivated field area nor affect yields negatively.