Soil pH
Soil pH is a measure of the acidity (low pH) or basicity (high pH) of a type of soil. There are various methods to measure the pH of a soil sample, normally using a mixture of soil and water. Soil pH controls many chemical processes within the soil, specifically affecting nutrient availability by altering the form of the compound in the soil. This dictates the ability of plants and other organisms to absorb nutrients for biological processes.