Lab Assignment #5 Questions

Please post questions about Lab Assignment 5 here.

What determines the capability of a parent material to supply plant nutrients? Is it true that soil dominated by finer particles such as clay can supply more nutrients than soil dominated by coarse particles?

Two things: 1) Mineralogy (ie the composition of rocks that make the parent material); if primary minerals dominate then such parent material will have limited charge, and

2) Size of particles in the parent material (small-size particles such as clay, have a large specific surface area)

And yes, clay size particles will hold (and eventually supply) more nutrients (ions) to plants than inert, sand-size particles

Hi, Maja, for question 2, is it because those four factors need time to have an affect on the formation of soil, so parent material has the most effect on the soil profile formation during the early stage?

yes, that is correct