Answer :
The amount of nutrients added to the tree subsystem in one year after leaf fall is 36 kg of nutrients.
What are plant nutrients?
Plants nutrients are the mineral elements required by plants for their growth and development.
Plant nutrients are mostly obtained from the soil as well as from the atmosphere.
Based on the data provided, each tree will absorb 23 - 21 Kg nutrients = 2 kg of nutrients
18 trees will absorb 18 × 2 = 36 Kg of nutrients.
Therefore, the amount of nutrients added to the tree subsystem in one year after leaf fall is 36 kg of nutrients.
Learn more about plant nutrients at: https://brainly.com/question/14366476
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