3.2.1 Chemical Analysis

Total metals, P and S in crushed rock, bottom ash and plant material were extracted by 7 M KHNO3 and determined by inductively coupled plasma optical emission spectrometry according to ISO 11885 (ISO 2007). The pH of the soil was deter­mined in a solid-water suspension (1:2.5, v/v). Readily available P, K, Mg, and Ca in soil were determined by extraction with 0.1 M ammonium lactate and 0.4 M acetic acid (pH 3.75) in a solid-to-solution ratio of 1:20 (w/v) (Egner et al. 1960). Nonexchangeable K was extracted by 1 M HNO3 according to Pratt (1965). The particle size distribution of the soils was determined according to Elonen (1971). Total N was determined as Kjeldahl N as described by Bremner (1960).