Finnish Society of Soil Sciences (Suomen Maaperätieteiden Seura ry) arranged a soil excursion in southwestern Finland to learn more about the clay soil profile in the area and the gypsum pilot. In total 15 soil experts took part in the excursion. The bus took us to Lieto and the Parmaharju water quality measurement site in the pilot area.
Project coordinator Eliisa Punttila (left) provided a presentation about the Pilot Gypsum on the bridge crossing the river Savijoki. The presentation followed by discussion on how the phosphorus load reduction is measured and how gypsum affects soil structure and microbiology. (Photo: Samuli Puroila)
After the gypsum presentation the group walked to a nearby field, where a large, more than 1 m deep holewas dug to demonstrate the layers of soil. Professor Markku Yli-Halla explained how the layers might have been born and what differences can be observed between the layers. (Photo: Eliisa Punttila)
Small plastic spoons show the boundaries of several different soil layers. Soil experts explained how the nutrients and solid matter move in the soil and how they end up in water courses. Runoff usually originates from the topsoil (approximately 20-40 cm from the surface) and leak to the drainage water through the channels and pores in the soil. As gypsum is spread on the soil, it reduces nutrient and solid matter leakage from top to bottom. (Photo: Eliisa Punttila)
In the gypsum area the harvest season is soon about to begin. This will be the first harvest after the gypsum treatment! (Photo: Eliisa Punttila)