Based on gaseous and stellar kinematic data from the DiskMass Survey, I will
discuss the relationship between the large-scale dynamical properties of
late-type galaxy disks and their star-formation activity. Among other
similar studies, ours is the first to use stellar velocity dispersions
observed in the cold regime of galaxy disks to measure both mass surface
density and disk stability via dynamical equations. Using disk-averaged
quantities, we find that the star-formation-rate surface density is
correlated with the stellar mass surface density and anti-correlated with
the two-component (gas+stars) disk stability. We show that this
anti-correlation can be predicted using a closed set of empirical scaling
relations, implying that it is reflected in other statistical properties of
star-forming galaxies. Finally, our data are consistent with an equilibrium
scenario derived assuming star formation occurs in the gravitationally bound
clouds of a multiphase interstellar medium that is in thermal and dynamical
pressure balance. Given their influence on the gravitational field
perpendicular to the disk, these results demonstrate that large-scale
properties, like stellar and dark-matter mass density, affect the
star-formation process in galaxy disks.