Organic matter in the soil provides all but which property?

Organic matter in the soil provides all but which property?

• A. Increases pH
• B. Improves water retention
• C. Improves soil structure
• D. Increases microbial activity

Answer: (A)

Organic matter strengthens soil health by multiple interrelated effects. It builds soil structure by promoting aggregate formation, which improves tilth, aeration, and drainage. It increases water retention because humus holds moisture like a sponge, helping plants survive dry spells. It also fuels microbial life, supplying carbon and energy that boost microbial activity and nutrient cycling. What it does not do in a guaranteed way is increase soil pH; organic matter tends to buffer acidity and help stabilize pH rather than simply raising it, and the actual pH effect depends on the soil’s starting conditions and the type of organic matter. So the property that is not provided is a guaranteed increase in pH.

Organic matter strengthens soil health by multiple interrelated effects. It builds soil structure by promoting aggregate formation, which improves tilth, aeration, and drainage. It increases water retention because humus holds moisture like a sponge, helping plants survive dry spells. It also fuels microbial life, supplying carbon and energy that boost microbial activity and nutrient cycling. What it does not do in a guaranteed way is increase soil pH; organic matter tends to buffer acidity and help stabilize pH rather than simply raising it, and the actual pH effect depends on the soil’s starting conditions and the type of organic matter. So the property that is not provided is a guaranteed increase in pH.