|Ocean Biochemical Cycling and Trace Elements|In: (2017). Encyclopedia of Geochemistry. Encyclopedia of Earth Sciences Series. Springer: Cham. ISBN 9783319391939. , meer
In: Encyclopedia of Earth Sciences Series. Springer: Dordrecht. ISSN 1388-4360; e-ISSN 1871-756X, meer
Dissolved inorganic carbon (C as DIC) varies around ~2 millimoles [mM = 10−3 M] in seawater and is pivotal for life in the sea. Much less abundant are the nutrients nitrate and phosphate that occur in the micromole [μM = 10−6 M] range and are essential for each living organism. Also essential for life are several trace nutrient elements , notably Fe and Zn, that occur in the nanomolar [nM = 10−9 M] range or even lower such as Co in the picomolar [pM = 10−12 M] range. Several other trace elements also occur in the nanomolar [nM] to picomolar [pM] range. Finally a few ultratrace elements occur in the femtomolar [fM = 10−15 M] range in seawater.