ENVB 210 Lecture Notes - Lecture 16: Hematite, Ion, Acid Rain
7 Feb 2018
School
Department
Course
Professor
Document Summary
Acid rain makes soils acid because hydrogen displaces cations. With great acid precipitations, the amount of hydrogen released in the soil is big a lot of cations are displaced and lost with anion leaching. Note: acid rain is not a problem in all situations. With a calcareous till as a parent material, there is enough. Ca, mg, k are critical for plant growth. (especially with deciduous trees) The base saturation for the cations should be: ca 80%, mg 10%, k 5% If ca decreases (around 45%) and we have 4% k, 8% mg, hydrogen occupies the rest. More generally, if base saturation decreases for the cations, hydrogen occupies the rest, which is not good for plant growth. Buffering capacity is the resistance of soil to ph change. Calculated by adding all the reactions that consume h+ or oh- added to the soil. Soils with high surface area (clay) ted to have a high buffering capacity.
