mud mechanics and aquatic flora/ fauna

For aquatic areas like spined lizard lagoon (swamp effect) would it be possible to integrate a mud mechanic which could have an effect?
bogged down on the dinosaurs according to their weight (the carnivore would be less impacted by the shape of their legs etc ...) obviously not on the whole area.
Also, could there be more diverse, taller and denser vegetation on spined. on some pond you put reeds (it would take spined) and why not
- Iris pseudacorus
-Victoria amazonica
- Salix babylonica
put a carpet of algae (like grass) at the bottom of the ponds,a lot of spined place is poor in vegetation and rock to interact .
New fish:
- sturgeon
- onchopristis
- Dipneusts (appears in dirty water)