What limits the net primary production in aquatic ecosystems such as lakes and streams?

Producers are the organisms which convert the sun's energy into food through the process of photosynthesis. In the lakes and streams simple microscopic floating plants called phytoplankton are the major producers. The amount of light energy converted to chemical energy by producers in a given time period is an ecosystem limits the net primary production in aquatic ecosystems such as lakes and streams.

the dark variety, as they are not visible on the dark tree barks

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