We determine the local metallicity of the ionized gas for more than 9.2 \times 10 ^ { 5 } star forming regions ( spaxels ) located in 1023 nearby galaxies included in the SDSS-IV MaNGA IFU survey .
We use the dust extinction derived from the Balmer decrement and stellar template fitting in each spaxel to estimate the local gas and stellar mass densities , respectively .
We also use the measured rotation curves to determine the local escape velocity ( V _ { \mathrm { esc } } ) .
We have then analyze the relationships between the local metallicity and both the local gas fraction ( \mu ) and V _ { \mathrm { esc } } .
We find that metallicity decreases with both increasing \mu and decreasing V _ { \mathrm { esc } } .
By examining the residuals in these relations we show that the gas fraction plays a more primary role in the local chemical enrichment than V _ { \mathrm { esc } } .
We show that the gas-regulator model of chemical evolution provides a reasonable explanation of the metallicity on local scales .
The best-fit parameters for this model are consistent with metal loss caused by momentum-driven galactic outflows .
We also argue that both the gas fraction and local escape velocity are connected to the local stellar surface density , which in turn is a tracer of the epoch at which the dominant local stellar population formed