What does pH measure in relation to soil?

pH is a measure of the acidity or alkalinity of the soil. It indicates the concentration of hydrogen ions in the soil solution and is expressed on a scale typically ranging from 0 to 14, with numbers below 7 indicating acidic conditions, 7 being neutral, and above 7 indicating alkaline conditions. Understanding soil pH is crucial because it significantly affects various soil properties, including nutrient availability, microbial activity, and overall soil health. Different plants have varying pH preferences, which can influence their growth and health.

In relation to the other choices, moisture content refers to the amount of water present in the soil, nutrient availability relates to the presence of essential soil nutrients, and temperature fluctuations deal with variations in soil temperature. While these factors are important for plant growth, they are not measured by pH. This highlights the specific role of pH in determining the soil's acidity or alkalinity, which is essential for proper soil management and crop production.