Particulate inorganic carbon

Particulate inorganic carbon (PIC) refers to the fraction of inorganic carbon that is present in solid particulate form in aquatic environments. This component mainly consists of carbonates, such as calcium carbonate (CaCO3), which are commonly produced by biological processes (e.g., from marine organisms like mollusks and corals) and geological processes (e.g., sedimentation and weathering of rocks).