Practice exam #3 - QUESTION 6

Fragment of a discussion from Course talk:APBI200

a. Goose soil is a gleysol, as diagnosed by the Bg horizon, and the fact that gleying is a dominant process in the soil from 15-55+ cm. b. . i. Advantages: good supply of organic matter, close to neutral pH, high concentrations of base-forming cations, structure above 25cm conducive to plant growth. ii. Disadvantages: poor drainage (as indicated by the fact that it is a gleysol, and the fact that it has massive structure), unfavourable ratios of Ca:Mg:K:Na, poor texture for plant growth, poor structure for plant growth below 25cm.

SpencerShields (talk)01:08, 28 April 2020

Yes, this is a Glesyol... and yes its diagnostic horizon is Bg (and gleying is also evident in ABg, BCg, Cgk)

Advantages:
Everything Spencer that you listed is correct, but for the full mark the explanation would need to be included too. For example, consider elaboration of the following :

  • -what are implications of good organic matter content? In other words, what other soil properties are impacted by high organic matter?
  • -what are implications of neutral pH?
  • -why is structure above 25cm in this soil conductive to plant growth? In what way?


Disadvantages:
Once again, what is listed is all correct, but elaboration/explanation is needed.
What is missing is mention of the fine texture, including a very low sand content. Then elaboration would be needed to explain what are consequences for other soil properties of such type of texture

MajaKrzic (talk)01:20, 28 April 2020