1. Different soil types develop in different climates.
Image: T. Loynachan
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2. Prairie soils have a dark surface layer (horizon), are rich in minerals, and form in grasslands widespread across Earth’s middle latitudes.
Images: NRCS
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3. Forest soils have a light gray upper horizon, a horizon rich in aluminum and/or iron, and form in warm to cool humid regions where coniferous forests grow.
Image: Soil Classifiers of Michigan
Image: Bruce Molnia
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4. Tropical soils are reddish and iron-oxide rich, depleted in nutrients, and form in humid and warm regions.
Images: National Cooperative Soil Survey, University of Nebraska
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5. Organic soils are dark colored, rich in decomposed organic matter, and form in poorly drained lowlands such as swamps and wetlands.
Images: Bruce Molnia, Soil Classifiers of Michigan
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6. Desert soils form in arid settings and are commonly rich in calcium carbonate.
Images: Martin Miller, NRCS
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7. Tundra soils form in Arctic environments, have a dark organic-rich upper layer, and a mineral rich layer over frozen ground.
Images: Travis Hudson, Alaska/Yukon Society of Professional Soil Scientists
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8. Different soil types develop in different climates.
Image: Image: T. Loynachan
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