Potassium contents of typical chernozem and dark grey forest soils with regard to their agricultural use and long-term applications of fertilizers

摘要

The effects of agricultural use and long-term applications of NPK fertilizers and manures on total potassium content and contents of mobile, exchange and acid-soluble forms of potassium in Chernozems and dark grey forest soils in the forest steppe region of Ukraine were investigated. Potassium content of soils decreased when fertilizers were not applied. Long-term applications of fertilizers stabilized and increased potassium contents of Chernozems and dark grey forest soils respectively. Effects of various fertilizer treatments are described.