What is the name for the measure of the interconnectedness of spaces in a material and how it controls how readily a rock or sediment will transmit fluids?

Permeability

permeability of any  medium or substance is directly proportional to its  fluid transmission ability  

Explanation:

Permeability measures the ability of any medium or substance to allow transmission of any substance through it  

The higher is the amount of free space with in any substance and medium, the higher is its ability to transmit other substances through it and hence higher is the permeability.  

Thus, permeability of any  medium or substance is directly proportional to its  fluid transmission ability  

1. loamy sand is about 80% sand with 10% clay and defined mostly by sand particles with some clay to provide structure and fertility. the sand particles are easily visible and the soil holds structure but breaks apart easily.

2. scott sand can improve his soil quality by incorporating more silt and organic matter into the soil. peat moss and organic matter can also be incorporated.

you didn't give any options but heres what i can tell you: an inference is likely to change based on additional observations. the latter is something that you have seen or sensed using your sensory organs while the former is like a conclusion out from what you have observed.