figure 2 illustrates the absorptions of Ni and Cd by corn and wheat during seeding stage in 6 programs. according to figure 3, the absorptions of Ni and Cd by wheat were obviously lower than those by corn. the concentrations of Ni and Cd in experimental groups of II-VI were gradually increased with the increase of composted sludge in comparison with the control group. but the corn had basically the same absorption capacity for Ni and Cd , with the absorption coefficient kept in low level ranging from 0.02 to 0.05 In contrast, the difference between the absorption coefficients of Ni and Cd corn was great. however, both the absorption concentrations of Ni and Cd by corn and wheat were low, with a maximum absorption coefficient only 0.17. according to the calculation, the absorption coefficients of Ni and Cd by crops were approximately in the range of 0.02-0.17 and 0.02-0.12 respectively.