Evolution of surface [Fe/H] (top panel) and A(Li) (bottom panel) according to T_eff, for three models with a mass of 0.78 M_⊙ and [Fe/H]_ini = −3.0 on the main sequence. No accretion was taken into account in these models. The magenta dotted line, the blue dashed line and the green line correspond, respectively, to the models with no other mixing than standard convection, with T5.80 turbulence and with T6.24 turbulence. The horizontal black dashed line represents the initial abundances of the models.