1. Department of Soil Science and Microbiology, Poznan University of Life Sciences, Szydłowska 50, 60-656 Poznan, Poland
2. Regional Chemical and Agricultural Station in Poznan, Sieradzka 29, 60-163 Poznan, Poland
3. Department of Geriatrics, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, Jagiellonska 13/15, 85-067 Bydgoszcz, Poland