maaperän

Maaperään is the illative singular form of the Finnish word maaperä, meaning into the soil or into the ground. In Finnish, illative forms are used to express movement toward or into a place or substance, so maaperään specifies direction toward soil or soil-like material.

Maaperä refers to soil, earth, or a substrate—the layer supporting plant life and various biological and chemical processes. In agricultural, ecological, and geotechnical contexts the term is common, and maaperään is used when discussing actions that involve placing something into the soil or moving into soil from above.

Usage examples are common in technical and everyday language. For instance, siemen istutetaan maaperään means “the seed is planted into the soil,” and lannoite levitetään maaperään means “the fertilizer is spread into the soil.” The illative form can also appear with verbs of deposition or incorporation, such as aineet, humus, or other substances being introduced into soil.

Etymologically, maaperä is a compound built from maa (“earth, ground”) and perä, a suffix forming nouns that denote material or substance. The illative suffix -ään attaches to the stem to indicate movement into the substance, yielding maaperään.

See also: Finnish grammar, illatiivi (illative case), maaperä (soil).