Distribution in ocean
Ge has a nutrient-like vertical profile
with concentrations that increase with depth (data).
The concentration is very highly correlated
with that of Si, which lies above Ge in the periodic table. Diatoms are
unable to discriminate between Ge and Si when they form their tests, and Ge
cycles as a Si analogue.
Speciation
Germanium is present in seawater as H2GeO3.
Residence time
The residence time was estimated based on analogy with Si.
Analysis
Germanium is determined by hydride generation followed by graphite furnace
atomic absorption spectrometry.