What is primary productivity? Why does it vary in different types of ecosystems?

CBSE Class 12 CBSE Class 12 Biology
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1
  1. What is primary productivity? Why does it vary in different types of ecosystems?
  2. State the relation between gross and net primary productivity.
2
  1. Primary productivity : Production of biomass/produced energy per unit area in a certain time period by plants during photosynthesis.It depends upon - plant species inhabitating a particular area, environmental factors availability of nutients, photosynthetic capacity of plant.
  2. GPP - R = NPP
    where,
    NPP = Net Primary Productivity
    GPP = Gross Primary Productivity
    R = Respiration Losses