The maize seedlings retained much higher concentration of Cd in
there was no significant difference of the total soil Cd among the
three series of experiments. An increase of total Cd in soils resulted
in an increase of water and CaCl2 extractable Cd. The 0.01 M CaCl2
could generally extract more Cd thanwater from the same soil, and
with respect to each of the two extractants the extractable Cd for
soils treated with only earthworms and soils treated with only
maize plants at the same Cd level was similar. The co-presence of
both earthworms and maize plants in soils could significantly
enhance the extraction of soluble Cd compared to that in corresponding
soils with only earthworms or with only maize plants.
This indicated that the co-presence of earthworms and maize
plants had great impacts on the mobility and availability of Cd in
soil.