Question

sep use mathematics a population of top predators consumes 7 kcal/m² per year. if the ecosystem has four trophic levels, how much energy is available to the primary consumers?

Explanation:

Step1: Recall energy - transfer rule

In an ecosystem, about 10% of energy is transferred from one trophic level to the next.

Step2: Let the energy available to primary consumers be $x$.

The top - predators are at the fourth trophic level. The energy they receive is 7 kcal/m² per year.
The energy transfer from primary consumers (second trophic level) to secondary consumers (third trophic level) is 0.1$x$, and from secondary consumers to top - predators (fourth trophic level) is 0.1×(0.1$x$) = 0.01$x$.

Step3: Set up an equation.

We know that 0.01$x$ = 7.

Step4: Solve for $x$.

Dividing both sides of the equation by 0.01, we get $x=\frac{7}{0.01}=700$ kcal/m².

Answer:

700 kcal/m²