7.4 Trophic levels in an ecosystem (biology only)

Medium

Fish farmers can optimize the growth rate of farmed fish by managing their feed and environmental conditions.

An aquaculture facility has 2200 tilapia in a farming system.

The farmer feeds the tilapia with dry spirulina algae grown in photobioreactors.
1 hectare of photobioreactor footprint produces 11.4 tonnes of dry spirulina.
The dry spirulina has an energy content of 18 MJ per kg.
Tilapia can use 80% of the energy present in the spirulina.
Each tilapia requires 58 MJ of energy to grow to harvest size.

Calculate the photobioreactor footprint area needed to provide enough energy from spirulina for 2200 tilapia to grow to harvest size.

Give your answer in $m2\text{m}^2$ .

Give your answer to 3 significant figures.

1 hectare = 10,000 $m2\text{m}^2$

1 tonne = 1000 kg

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7.4 Trophic levels in an ecosystem (biology only) Questions