What does pH measure in soil?

pH in soil is a critical measurement that indicates the acidity or alkalinity of the soil. It is measured on a scale from 0 to 14, where values below 7 indicate acidic conditions, values of 7 are neutral, and values above 7 signify alkaline conditions. This measurement is important for several reasons.

First, soil pH affects the availability of nutrients to plants. Different plants thrive at different pH levels, so understanding the soil's pH can aid in selecting appropriate plants for a specific area. Additionally, pH influences microbial activity and the overall health of the soil ecosystem.

Acidic soils might limit the availability of essential nutrients such as calcium and magnesium, while alkaline soils may restrict iron and copper availability, both of which are vital for plant health. Therefore, recognizing the pH level helps in making informed decisions about soil amendments and modifications to optimize plant growth and health. The other options listed do not directly relate to what pH measures; moisture level, nutrient level, and organic matter content would require different tests and indicators to assess properly.