The amount of biomass produced by the plants through photosynthesis minus…

2024

The amount of biomass produced by the plants through photosynthesis minus respiration losses in a given time period is known as:

  1. A.

    Gross Primary Productivity

  2. B.

    Net Primary Productivity

  3. C.

    Gross Ecological Productivity

  4. D.

    Net Secondary Productivity

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Correct answer: B

Answer: Net Primary Productivity

Definition: Net Primary Productivity (NPP) is the rate at which plants accumulate biomass in a given time period after subtracting the energy they use in respiration.

  • Key formula: NPP = GPP − R (where GPP is Gross Primary Productivity and R is plant respiration).

  • Units: commonly expressed as mass of carbon or biomass per unit area per time (for example, g C m−2 yr−1).

Why the other choices are incorrect:

  • Gross Primary Productivity: This is the total carbon fixed by photosynthesis before subtracting plant respiration, so it does not represent the net biomass remaining.

  • Gross Ecological Productivity: This is not a standard term for plant production after respiration and is ambiguous; it is not the accepted term for the quantity asked.

  • Net Secondary Productivity: Refers to biomass produced by consumers (animals) after their respiration, not to plant biomass, so it is not the correct answer.

Summary: The correct term for plant biomass produced through photosynthesis minus plant respiration losses is Net Primary Productivity (NPP).

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