  We study turbulent dissipation in the ISM and explore some implications for
galaxy formation and evolution using 2D MHD numerical simulations of
compressible fluids. The turbulent kinetic energy E_k is injected by stellar
sources formed self-consistently in the simulation. In the ISM-like fluid,
regimes of both forced and decaying turbulence coexist. In the active turbulent
regions (forced regime), E_k is dissipated locally and efficiently. In the
decaying regime (far from input sources), E_k(t) decays ~(1+t)^-0.8. The
residual turbulent motions may propagate distances of the order of the observed
disk height, suggesting that turbulence may be the responsible of vertical
support and star formation self-regulation at the disk level, but not at the
level of the whole cosmological halo, as would be required in some models of
galaxy formation.
