Gypsum amendment of arable fields as a water protection measure – farmers’ experience, phosphorus reduction potential and associated costs drawn from a large scale pilot

Authors

• Markku Ollikainen University of Helsinki
• Anna-Kaisa Kosenius University of Helsinki
• Eliisa Punttila University of Helsinki
• Venla Ala-Harja University of Helsinki
• Samuli Puroila University of Helsinki
• Antti Iho Natural Resources Institute Finland (Luke)
• Petri Ekholm Finnish Environment Institute

DOI: https://doi.org/10.23986/afsci.88902

Abstract

We organized a large-scale pilot on gypsum amendment of arable fields in southwest Finland, along the River Savijoki to examine its effects on phosphorus loads and aquatic environment, and to assess its feasibility as a water protection measure. This paper reports findings on the feasibility aspects of gypsum amendment covering logistics and costs of spreading, abatement potential and farmers’ experience. We found that farmers perceived gypsum amendment positively and the costs of reducing phosphorus are low relative to other measures available in agriculture. Gypsum amendment suits well to 0.5 million hectares of arable land in southern Finland. Gypsum could potentially contribute considerably to the achievement of phosphorus reduction targets of the Baltic Sea Action Plan if applied in all countries having clay soils.