Question

If the secondary consumer in an ecosystem has 560 kcal/m2yr of energy, how much energy do the producers have?(1 point)
Responses

56,000 kcalm2yr
56,000 kcalm2yr

5.6 kcalm2yr
5.6 kcalm2yr

56 kcalm2yr
56 kcalm2yr

5,600 kcalm2yr

Answer 1

In ecological energy transfer, we often use the concept of trophic levels and the 10% rule, which states that approximately 10% of the energy from one trophic level is transferred to the next level.

If the secondary consumer has 560 kcal/m²/year, to find the energy available to the producers (which is two trophic levels below the secondary consumer), we can apply the 10% rule twice:

1. From producers to primary consumers: 10% of producers' energy goes to primary consumers.
2. From primary consumers to secondary consumers: 10% of primary consumers' energy goes to secondary consumers.

Let’s denote the energy available to producers as \( P \):

1. Energy available to primary consumers = 0.1 * \( P \)
2. Energy available to secondary consumers = 0.1 * (0.1 * \( P \)) = 0.01 * \( P \)

Now we know the energy available to secondary consumers is 560 kcal/m²/year, so we can set up the equation:

0.01 * \( P \) = 560 kcal/m²/year

To find \( P \):

\( P = \frac{560 kcal/m²/year}{0.01} \)
\( P = 56000 kcal/m²/year \)

So, the energy available to the producers is **56,000 kcal/m²/year**.