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.
Category: Biology Published: January 5, 2013. All of earth's oxygen does not come from trees. Rather, the atmospheric oxygen that we depend on as humans comes predominantly from the ocean. According to National Geographic, about 70% of the oxygen in the atmosphere comes from marine plants and plant-like organisms. These ocean-living plants release molecular oxygen as a waste product of photosynthesis (as do most plants).