  In turbulent flows subject to strong background rotation, the advective
mechanisms of turbulence are superseded by the propagation of inertial waves,
as the effects of rotation become dominant. While this mechanism has been
identified experimentally, the conditions of the transition between the two
mechanisms are less clear. We tackle this question experimentally by tracking
the turbulent front away from a solid wall where jets enter an otherwise
quiescent fluid. Without background rotation, this apparatus generates a
turbulent front whose displacement recovers the $z(t)\sim t^{1/2}$ law
classically obtained with an oscillating grid and we further establish the
scale-independence of the associated transport mechanism. When the apparatus is
rotating at a constant velocity perpendicular to the wall where fluid is
injected, not only does the turbulent front become mainly transported by
inertial waves, but advection itself is suppressed because of the local deficit
of momentum incurred by the propagation of these waves. Scale-by-scale analysis
of the displacement of the turbulent front reveals that the transition between
advection and propagation is local both in space and spectrally, and takes
place when the Rossby number based on the considered scale is of unity, or
equivalently, when the scale-dependent group velocity of inertial waves matched
the local advection velocity.
