What are the factors affecting osmosis (bio)?
Osmotic flow is the movement of a substance (typically water), across a semi-permeable membrane, from the side on which the chemical potential of the substance (water) is higher to the side on which it is lower.  I.e., just as temperature provides a gradient for the flow of thermal energy, chemical potential provides a gradient for the flow of matter.

Thus anything that affects the chemical potential of water will affect osmotic flow.  This includes dissolved solutes, pH (which of course comes from a particular dissolved solute—H$^+$), temperature, and pressure. For instance, increasing the solute concentration decreases water's chemical potential, while increasing the pressure increases it.  

Indeed, that's the basis of osmotic pressure—water will flow toward the side with the greater solute concentration (activity) until the pressure on that side increases enough such that the reduction in water's chemical potential due to the presence of the dissolved solutes is exactly negated by the increase in water's chemical potential due to the increased pressure.