The Dry Mixedgrass Soils
The characteristics soils of the Dry Mixedgrass Subregion are Dark Brown
Chernozems, which typically develop under grasslands. Brown Solonetz soils are common in the extreme southeast of the subregion
and in a large area north of Dinosaur Provincial
Chernozems are a typical prairie
soil. They were formed only 100,000 years ago under aerobic conditions where water flowed freely through the upper layers. They were created by the sudden and rapid addition of organic matter, along with lots of humidification.
If you were to look at a cross-section of a chernozem, you might see things like earthworm tracks and animal burrows filled in with different types of soils. Animals like these aerated the soils and were crucial in the formation of Chernozems.
Although there are many different kinds of Chernozems, there is very little difference between them. One interesting fact is that Black Chernozems are formed because of lots of precipitation in that particular area.
Chernozems are generally dry, and as such, can only support vegetation like tall grasses. Sometimes, though, patches of
deciduous woodlands can grow as well.
Solonetz is a typical prairie soil, like the Chernozems, and they're usually found together. Solonetz soils are most common in areas where the amount of rain is less than the amount of transevaporation from the soil. Because of that, there is usually not enough moisture in the soil to support a complete plant cover. The pH of the soil is also too high to grow much vegetation.
Solonetz soils were formed during the Holocene
period, and are made up of unconsolidated materials, including glacial deposits. They are confined to flat or gently rolling areas, but are absent from depressions where the water table comes near the surface.
Information provided by and printed with the permission of Alberta
Community Development, Parks
and Protected Areas.