I was recently sent on a soil survey for work!
In Alberta, soil surveys for natural resource companies are usually done before excavation to keep track of which soil is high quality enough to be saved as reclamation material after work is finished in the area. For more information on how this reclamation material is used, check out this post.
Many people think soil is simple and worthless, but good quality soil is a finite resource, due to the difficult factors that go into it’s formation. In Canadian soil science, there are 5 factors of soil formation: Relief (Topography), parent material (In Canada almost always glacial sediment), climate (wind and rain weathering), Organisms, and time. These five factors cause physical processes to happen to the soil.
In Canada, mineral soil science focuses on classifying soils by subgroups, based on what physical processes they had undergone (gleying, elluviation, etc) and then compared that with what parent material they had originated from (glacial till, glaciofluvial, etc) to get a soil series.
When we find organic soils (>40cm of organic material), we focus on the degree of decomposition (fibrisol, mesisol, humisol) and depth of each layer and the depth to mineral contact to determine the subgroup and series.
Soil series are different in different regions, and they help define which soils are worth keeping and which aren’t. We would also classify different areas’ ecology in order to help the client restore that area to it’s former state after reclamation.
Most soils we found were classified exactly as expected, due to our soil series map already being quite robust, and nearby soils will not change dramatically if there isn’t a large change in topography or ecology. The few times we would find unexpected soils were when there was nearby disturbances in soil, for example beaver activities raising and lowering water levels or small rivers whose water level would change periodically in the year. Root bulbs (uprooted trees) would also cause soil series to fluctuate due to the tree physically loosening the soil horizons.
Overall, this was an amazing experience and I can’t wait to do another project like this.
Jaron Wiigs 