Soil pH was measured in a
1:2.5 (w/v) ratio of soil to deionized water using a pH meter. Available Cd was
determined using a diethylenetetraminepentaacetic acid (DTPA) extraction
(0.005 M DTPAþ0.01 M CaCl2þ0.1 M triethanolamine (TEA), pH¼7.3, solution:
soil¼2:1, extraction for 2 h