Question

How do microorganisms contribute to the health and characteristics of soil?

Answer 1

Humus affects soil properties. As it slowly decomposes, it colours the soil darker; increases soil aggregation and aggregate stability; increases the CEC  and contributes N, P and other nutrients.Soil organisms, including micro-organisms, use soil organic matter as food.

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Answer 2

Whenever their biodegradable materials in the soil, the microorganisms feed of then and turn them into useful chemicals which are good for the soil