desiccation

Desiccation is the process of extreme drying or the removal of moisture from a substance or organism. The term derives from the Latin desiccare, meaning to dry up. Desiccation can refer to drying of biological tissue, foods, soils, or materials, and to natural environmental conditions that reduce humidity. In many contexts it is a deliberate preservation method, while in others it is a consequence of climatic or microbial activity.

In biology, desiccation describes extreme dehydration of organisms or cells. Some species tolerate desiccation through desiccation tolerance or anhydrobiosis, entering reversible states of suspended metabolism. Protective mechanisms include the accumulation of sugars such as trehalose, stabilization of proteins and membranes, and the formation of vitrified intracellular glass. Seeds and spores often exhibit innate desiccation tolerance, enabling long-term storage.

Practically, desiccation is achieved by drying, evaporation, or removal of water using heat, air flow, or desiccants. Techniques include sun and oven drying, spray drying, and freeze-drying (lyophilization). Desiccants like silica gel absorb moisture to protect goods. In ecology and geology, desiccation refers to soil and habitat drying and to features like desiccation cracks following evaporation. Desiccation can preserve specimens but may also damage sensitive materials if excessive and irreversible upon rehydration.