Hourly Forecast Detailed. 1  0am:The Santee, SC forecast for Apr 11 is 63 degrees and Clear. There is 74 percentage chance of rain and 4 mph winds from the South-Southeast. 2  3am:The Santee, SC forecast for Apr 11 is 55 degrees and Clear. There is 79 percentage chance of rain and 4 mph winds from the South.
Most Important Organism? Marine plants produce between 70 and 80 percent of the oxygen in the atmosphere.
Photosynthesis from plants use carbon dioxide, sunlight, and water and a byproduct is oxygen. Before humans existed, the earth existed for millions of years creating an enormous supply of oxygen. Organisms and plants created a balance of oxygen and CO2. The Earth's net supply of oxygen comes from phytoplankton. Plants produce oxygen but use up what they make by producing carbon dioxide at night and when they are burned or decompose, so you see, the only thing that keeps us breathing is the tiny phytoplankton in the sea.