The equation (P = ρ g h) and relationship between pressure and liquid depth is well understood for open water bodies.
Question one, would this equation and relationship still be applicable to the water pressure measured in sediment for a static (no flow) water body?
Question two, would this differ for a flowing body of water like a river or stream?
These question originate from the measurement accuracy of pressure loggers in dynamic sediment environments where loggers from time gets buried in sediment. Any reference to supporting literature would be appreciated.
Your equation represents the weight of a column of liquid over an area A. It assumes that there are no lateral forces and that the weight force is transmitted from the top of the column to its bottom in such a way that each layer presses onto the layer below it.
If you have a suspension of freely floating particles, the equation is valid as long as the density is constant; otherwise you have to use
P = integral0h rho(h) d h
The equation ought to be applied with caution if the sediment particles are touching each other. A device measuring the weight force at the bottom
of a column of wet, packed sand would register the weight of the water and the sand, whereas a device measuring the refractive index of water would merely record the hydrostatic pressure of the water.
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