Is this mould or fungus in my sub floor?

Hello all

I was crawling around my sub floor space to check for water issues. Our subfloor flooded a couple weeks back during a heavy storm and we're currently trying to sort it out. Already installed extractor fans and a couple vent holes to help with the ventilation.
Imgur

What surprised me was finding these white/yellow fluffy things scattered on top of the soil, I am not sure whether it is mould or fungus.

We're not sure what to do with this, we are the new owner but the house is really old, so appreciate any advice that can be given!

 

It’s a type of mould. This liknk explains all about it and how to treat it.
Mould and your health