Soil density refers to the mass of soil per unit volume, typically expressed in grams per cubic centimeter (g/cm³). It is an important property that helps determine the soil's ability to support plant growth, retain water, and provide habitat for organisms. Soil density can vary based on factors such as soil composition, moisture content, and compaction. There are two main types of soil density: bulk density and particle density. Bulk density includes the weight of both the soil particles and the spaces between them, while particle density only considers the weight of the soil particles themselves. Understanding soil density is crucial for agriculture, construction, and environmental management.