Table 1.

Predicted activities of Ca²⁺ and Al³⁺ in basal solution from the measured Al concentrations used in Experiment 1 (measured values are the average after 0 and 120 h)

Nominal Al (µm)	Measured Al (µm)	Ca2+ activity (µm)	Al3+ activity (µm)
0	1.02	782	0.57
25	25.6	778	13.1
50	49.4	775	24.9
100	93.1	768	46.1
150	142	760	69.0
200	184	754	87.8
250	229	748	107
300	280	741	129
600	545	710	229
1000	929	675	351

The Al³⁺ activity was calculated from measured Al concentrations, and the Ca²⁺ activity was calculated from nominal Ca concentrations.

Total concentration of Ca: 1000 µm.