Given below are two statements: Statement I: The primary source of energy in an ecosystem is solar energy. Statement II: The rate of production of organic matter during photosynthesis in an ecosystem is called net primary productivity (NPP). In the light of the above statements, choose the most appropriate answer from the options given below:

Solution & Explanation

Answer: (A) Statement I is correct: solar energy is the basic input that drives every ecosystem. Statement II is incorrect because the rate of production of organic matter during photosynthesis defines GROSS primary productivity (GPP), not NPP; NPP is GPP minus respiration losses. Hence only Statement I is correct, option (a). NCERT Reference: Ch 12, p.207 — “productivity of an ecosystem is the rate of production of organic matter”