Soils {soil, land} have types and properties {pedology}|. Soil comes from eroded rocks and decayed organic matter. Soil {mountain soil} derived from lava is rich in minerals. Iron oxides cause red, yellow, or brown soil color. Humus causes black or dark-brown soil color. Soil can be acid or alkaline. Soil has layers.
Physical Sciences>Earth Science>Land>Soil
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Date Modified: 2022.0224