  Numerical calculations based on the recursive Green's functions method in the
tight-binding approximation are performed to calculate the dimensionless
conductance $g$ in disordered graphene nanoribbons with Gaussian scatterers.
The influence of the transition from short- to long-ranged disorder on $g$ is
studied as well as its effects on the formation of a perfectly conducting
channel. We also investigate the dependence of electronic energy on the
perfectly conducting channel. We propose and calculate a backscattering
estimative in order to establish the connection between the perfectly
conducting channel (with $g=1$) and the amount of intervalley scattering.
