Surface density (left) and midplane solid-to-gas ratio (right) for the case of F_p/g = 0.3, Ṁ_gas = 10⁻⁸M_sun yr⁻¹ and K = 0. Top panels: cases of the turbulent viscosity of α_tur = 1 × 10⁻³. Bottom panels: case of α_tur = 3 × 10⁻³. In each panel, solid and dashed lines represent the cases of the effective viscosity of α_acc = 3 × 10⁻³ and α_acc = 1 × 10⁻², respectively. In the left panel, blue, brown and green lines represent those of ice in pebbles, silicate in pebbles and silicate grains, respectively. In the right panel, blue and green lines represent those of pebbles and silicate grains, respectively.