2.8. Soil chemical analysis
Soil moisture content was estimated by an oven dry weight
method, and the pH was determined using a glass electrode
meter in a suspension containing a 1:5 soil/water ratio (w/v).
Electrical conductivity (EC) was measured for the water extracts
containing the 1:5 soil/water ratios (w/v). Total organic C (TOC)
and total N (TON) contents were determined by a dry combustion
method using an Element Analyzer (Vario EL, Germany). NHþ
4 N
and NO
3 N were extracted with 0.01 M CaCl2and the concentrations were determined by an Auto Analyzer (Auto Analyzer 3,
Germany).