Browsing by Author "Yrjölä, Karoliina"

Most of the ammonia emissions caused by agriculture is a result of manure management. Acidification has been indicated to be an effective method to reduce ammonia emissions from slurry. The main target of this study was to compare the effect of acidified slurry on spring wheat yield. The objective was also to investigate how much the slurry acidification improves the crop nitrogen intake. The field experiment of this study was done in the summer 2017 in Helsinki. There were four members in the experiment; unfertilized zero plot, NPK -control plot, a plot with unacidified slurry and a plot with acidifield slurry. The slurry that was used in this study was from a sow piggery. The amount of the sulphuric acid needed to acidify the slurry was calculated on the strength of the titration tests that were done in laboratory. The slurry was spread on the field surface in early June when the crop was in 2-3 leaf stage. The slurry was acidified just before the spreading. According to the results, in the circumtances where this study was taken the slurry acidification did not improve the growing conditions of spring wheat. The acidification of slurry may improve the crop nitrogen intake, but the benefit varies in different years and it depends on the conditions of the growing season. For example if there is a lot of soluble nitrogen in the arable land, the effect of acidificated slurry on crop yield can not be seen. Also the quality of the slurry and the circumstances of the spreading time affect to the benefits of the slurry acidification. Before the acidification can be carried out widely in farms there must be done more research. One option could be that a contractor who is familiar with the acidification technique and knows how to handle sulphuric acid would do the acidification in farms and could do also the spreading more cost-effective.