A "Caliche Layer" in Soil Is

question 8

Multiple Choice

A "caliche layer" in soil is

• A) a hard layer formed by precipitation of calcium carbonate (CaCO₃).
• B) a hard layer formed by precipitation of nitrates (KNO₃, MgNO₃) from over-fertilization.
• C) a water-absorptive layer of peat.
• D) a layer of younger soil overlaying an old, depleted soil.
• E) a layer polluted with heavy metals.

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Definitions:

Trophic Category

A classification describing the feeding position and role of an organism in an ecosystem's food chain or web.

Primary Consumer

Organisms that feed on primary producers or autotrophic plants, forming the second trophic level in the food chain.

Herbivore

An animal that primarily eats plants or plant-based materials.

Producer

Organisms, often photosynthetic plants or algae, that create organic matter from inorganic substances, serving as a foundational energy source in an ecosystem.