Where would you find humus in this photograph

I would probably say that the answer is D. On top of the dark band as humus is usually occurring in the topsoil. Humus refers to the natural decay of material such as leaves in the top layer of the soil.

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An ecosystem is in a certain area and includes living and non living plus there is weather conditions and a biome is a large amount of area with similar climate.so ecosystem is based on weather and biome is based on the average climate