First off, predictive soil mapping takes the information from the soil surveys in the 80s and 90s that were limited by technology, and improves the resolution of the generated maps and overlays polygons digitally, that contain more soil information.
“Instead of knowing each polygon has three or four different soil types, you actually have an idea of where on the landscape those soil types will be found, and then by association what the strengths and weaknesses are of those different soils are within the field,” says Dr. Angela Bedard-Haughn, professor of soil science at the University of Saskatchewan. “This is really important when you think about all the management tools, you know precision agriculture tools, that we have at our disposal now.”
Understanding what soil variables are affecting yield — beyond soil fertility — is important so you can manage appropriately and effectively, adds Bedard-Haughn. (Story continues below video).
So much of soil mapping so far has been a bit more academic in nature, which means a high number of soil samples and a lot of lab analyses. The number of samples is just too great to be economically viable for the producer or the agronomist, says Bedard-Haughn, and by partnering with CropPro Consulting, her lab can determine the appropriate number of samples to take that still provides reasonable results in predictive soil mapping.
“It’s taking into account, in the first place, what the variability of that field is and then sampling strategically so that you’re capturing that variability up front,” says Bedard-Haughn.
The primary assessments the project will collect, deal with top-soil colour and depth as a proxy for organic matter, indications of soil saturation, salinity constraints, carbonates and the influence on soil pH, as well as texture information. All of these measurements will be compiled with CropPro’s standard chemical analyses of samples, then the whole parcel of information will be run through predictive mapping algorithms.
The approach will work for more than just Saskatchewan soils, too — the way the algorithm works will operate the same on information from other provinces.
You can view the Saskatchewan Soil Information System app here.