The study points that, of all injuries sustained during girls soccer, 27% are concussion related. Of all injuries sustained during boys football, 24% are concussion related. I wouldn't expect girls soccer to have more total injuries than football.

The abstract didn't provide any comparison between the two sports for concussion rate (defined as the number of concussions per 10,000 athlete-exposures). The data might be out there, but this study doesn't tell me anything.