Sulawesi plots soil metals

Total C measurement used the Walkley and Black method, total N the Kjeldahl method and total soil Al, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, P and Zn was quantified via digestion of 0.5 g soil in 5 ml HNO 3 and 1 ml HClO 4 at 100 to 200 ° C by ramping over a 7 hour period then diluted to 25 ml with deionised water and analysis on an Agilent Technologies 4100 microwave plasma atomic emission spectrometer (Co, Cr and Ni) or an Agilent Technologies 200 Series atomic absorption spectrometer (all other elements).