SGD studies in Bohai Bay
(Liu et al. , 2017a; Yi et al. , 2019) both used radium
isotope tracer in Bohai Sea area to study SGD. Lixin Yi studied the
effects of geological lithology, human activity, terrestrial groundwater
activity, SGD flux rate, mixing process and geochemical environment
(salinity) on 223Ra, 224Ra and228Ra in different water bodies, demonstrating that
the relative level of isotopic activity in coastal groundwater and
coastal seawater is determined by the interaction between groundwater
and seawater. Jianan Liu used the mass balance model of226Ra and 228Ra to calculate that
SRGD had a much greater impact on Bohai Sea than SFGD. The value of SGD
he calculated was (2.0 ± 1.3) × 1011m3 /yr.