be default, the maraki AP (MRxx) transfers its management traffic over native VLAN (or access port).
if you want your SSID(s) in a different network segment:
1) use Meraki NAT: nothing else is required on the switch (access mode/port is enough)
2) use bridge mode:
2a) configure additional VLAN(s) on your meraki AP switch port (trunk mode).
2b) make sure you have a DHCP server within the additional VLAN(s)
2c) setup the additional VLAN(s) in the 'access control' setting, section VLAN tagging / VLAN id