  Nonlinear gyrokinetics provides a suitable framework to describe
short-wavelength turbulence in magnetized laboratory and astrophysical plasmas.
In the electrostatic limit, this system is known to exhibit a free energy
cascade towards small scales in (perpendicular) real and/or velocity space. The
dissipation of free energy is always due to collisions (no matter how weak the
collisionality), but may be spread out across a wide range of scales. Here, we
focus on freely-decaying 2D electrostatic turbulence on sub-ion-gyroradius
scales. An existing scaling theory for the turbulent cascade in the weakly
collisional limit is generalized to the moderately collisional regime. In this
context, non-universal power law scalings due to multiscale dissipation are
predicted, and this prediction is confirmed by means of direct numerical
simulations.
