Zinc cycle

Natural Cycle

Lithosphere

Zinc-containing minerals in the Earth's crust exist primarily as sulfides, such as sphalerite and wurtzite, and carbonates such as smithsonite. Zinc minerals enter the terrestrial environment through weathering and human activities. Zinc is used by plants and other organisms, and then enters aquatic systems where it either settles into sediments or eventually enter the oceans.

Oceans

Zinc is a marine micronutrient that tends to be in higher concentration in the deep ocean and is transformed into organic zinc which enters the food chain by diatom blooms during upwelling events in the Southern Ocean. Zinc settles to the ocean floor and is returned to the mantle from the subduction of marine sediments.

The zinc cycle has historically been characterized by episodic changes in zinc deposits. Major global events such as the formation or breakup of supercontinents and periods of significant volcanic activity tend to create new deposits of zinc in the lithosphere. In between these events, zinc tends to cycle through the biosphere at a lower rate of change.