With reference to the planet Earth, consider the following statements:
I. Rain forests produce more oxygen than that produced by oceans.
II. Marine phytoplankton and photo synthetic bacteria produce about 50% of the world’s oxygen.
III. Well-oxygenated surface water contains several folds higher oxygen than that in atmospheric air.
Which of the statements given above is/are correct?
- (a) I and II
- (b) II only
- (c) I and III
- (d) None of the above statements is correct
Answer: (b) II only
- Rainforests do not produce more oxygen than oceans. The ocean, particularly through phytoplankton, is estimated to produce a significantly larger portion of Earth’s oxygen than land-based ecosystems like rainforests.
- While estimates vary, the ocean is thought to produce a substantial portion of the world’s oxygen, ranging from 50% to 80%, while land-based ecosystems like rainforests contribute around 28%
- Marine phytoplankton are primarily responsible for a significant portion of Earth’s oxygen production, with estimates suggesting they produce between 50% and 80% of the oxygen in the atmosphere.
- Synthetic bacteria, while involved in oxygen production in some cases, are not the primary source of oxygen for the planet
- The concentration of dissolved oxygen in surface water is much lower than the concentration of oxygen in air. Air contains about 21% oxygen by volume, which is significantly higher than dissolved oxygen levels in water (typically around 8–10 mg/L).
