Cocci of phosphate-sequestering bacteria were found in the water colum
n off Namibia where Recent phosphorites are forming. Furthermore, rece
nt work on bacterial populations in the Benguela upwelling system show
s that the population that occurs during non-upwelling periods is domi
nated by phosphate-sequestering bacteria (Pseudomonas, Acinetobacter).
These are the bacteria that effect phosphorus removal from biological
activated sludge systems in wastewater treatment plants. Our conclusi
on is that these bacteria act in a similar manner in natural systems a
s they are known to do in wastewater treatment plants and that they pl
ay an active role in phosphate concentration and phosphorite genesis.