Final Exam Questions
Hi Maja, could you please tell me what is the distinction between soil association and soil complex? Thank you very much.
Yes Maja, I read through the lecture notes and I also asked several friends. However, none of them can clearly demonstrate what should we write when we are required to write the distinction between two terminologies. For example, if I write the distinction between soil association and soil complex, I would write "Soil association only represents one group of taxonomic soil, which is simple for people to predict the utility of that soil. Soil complex consists of several groups of taxonomic soil which intermix together, so soil complex is complicated for people to manage." Does it sound right? I always feel that I am repeating the definitions of those two terminologies. Thus, with all respects, could you please provide a sample distinction about soil association and soil complex for us? (By the way, all of my friends in APBI200 got -3 for all the sub-questions of the first question of the midterm. That's the reason why we really want to read a standard distinction.)
Thank you very much!
Here are the definitions (copied from the lecture notes) Soil association. A mapping unit in which a group of taxonomic soil units occur together in a regular pattern in about the same relative proportions throughout a geographic region (comparable to plant associations in many ways).
Soil complex. A mapping unit used in detailed soil surveys where two or more defined taxonomic units are so intimately intermixed geographically that it is undesirable or impractical (because of the map scale being used) to separate them.
Distinction: Soil complex represents a more intimate mixing of smaller areas of individual taxonomic units than that described under association. Also, these small areas of individual taxonomic units are not present in the same relative proportions within the soil complex.
Hi Maja, I'm slightly confused about question 5 on the 2005 final exam: List and briefly explain inputs and losses of soil phosphorus and sulfur.
I got that soil phosphorus will be lost through plant removal, erosion of phosphorus-carrying soil particles, and phosphorus dissolved in surface runoff water. However, I'm not too entirely sure what the inputs are.
Also, I looked all around online and in the textbook and was only able to find the following for inputs and outputs of soil sulfur, are these correct? Inputs: Use of highly concentrated fertilizers, mineralization of organic matter in release of plant-available sulfur Losses: Intensive cropping systems that increase crop yields causing more removal of sulfur from the field
Thanks for your help, Sophia
The most efficient way to answer this question would be to go to the lecture notes from March 14 and to check P & S cycles that are included there. All the losses are indicated by the orange lines, while all the inputs are indicated by blue lines.
If those slides are too small, you can also access them at our SoilWeb200 online tool (http://soilweb200.landfood.ubc.ca/). P cycle is available at http://soilweb200.landfood.ubc.ca/soil-biology/nutrient-cycles/2-phosphorus-p/, while S cycle is available at http://soilweb200.landfood.ubc.ca/soil-biology/nutrient-cycles/3-sulphur-s/