Evolution of the surface Li abundance and ⁴He in mass fraction (solid and dashed lines respectively) as a function of age in models with M = 0.74 M_⊙, [Fe/H] = −2.0, [α/Fe] = 0.3 with no additional viscosity and parametric turbulence(red line), with additional viscosity but without parametric turbulence (orange line), and with both taken into account (with log T₀ = 6.28, blue line). The light blue band around the solid blue line indicates the A(Li) evolution for models with ν_add = (3.5 ± 1.5)×10⁴ cm² s⁻¹ and parametric turbulence (log T₀ = 6.28). The green lines are for a model with ν_add = 3.5 × 10⁴ cm² s⁻¹ and parametric turbulence as in Pop I stars (log T₀ = 6.42). All the models include rotation at the median rate.