Problem Set #2 Questions

Q.For question 3c, do I need to calculate the bulk density or just estimate to 2.65? Since in 3b, the soil is unsaturated, so the density maybe different.

A. You should assume particle density of 2.65 g/cm3 (and this is particle density, not bulk density). Particle density is NOT affected by the water content.

Q. re. question 4b, I don't really know the soil condition of BC forest, is that just because there is too much rain, so the Al ions are washed away, so it's less acidic? Or anything else?

A. Pls refer back to the lecture slide (shown on Friday Feb 7)showing the most common ranges of pH values in soils in humid & arid regions. I went over this explanation in the class and there is similar explanation in the textbook from where that slide was taken. Hint - coastal BC has a humid climate and Al is not as easily washed out of the soil as some other ions (e.g. Ca, and Mg).