||Surface waters where rapid growth and very high densities of diatoms occur. Diatoms
are large cells and tend to have high nutrient requirements. Spring diatom blooms
occur in many estuarine and coastal waters, as diatoms have low light requirements
and are well adapted to the hydrologic period when turbid riverine inputs are highest.
They have higher nutrient requirements than other groups and require silica, needed
to produce frustules. Land runoff contains silica making the spring period ideal for
formation of coastal diatom blooms. The rise of the bloom is important in initiating
food webs of zooplankton and other grazers and the decay of the bloom is important
in nutrient cycling, and potentially contributes to the later formation of hypoxic
bottom water as organic material accumulates in the lower water column.