20. Complete the energy pyramid by writing the source of the energy for the food web and
how much energy is available to first-, second-, and third-level consumers.
Heat
Third-level consumers
Second-level consumers
_First-level consumers
100% Producers

A graphical representation of energy in a pyramid structure of ecology or trophic levels of an ecosystem is called an energy pyramid. It represents the producers and consumers of an ecosystem.

In a food chain and web, the energy and biomass shift from one level to another and the source of energy is heat or sun.

This change in energy transfer is due to the 10% rule according to which the 10% energy decrease with each level when one moves from the level of primary producers to third-level consumers.

Therefore, energy decrease when a level increase in pyramids.

Learn more about energy pyramids here:

link

The source of energy for the food web is heat, i.e. the Sun. Since 100% energy is available to the producers, the first-level consumers have 10%, the second-level 1%, and third-level 0.1%. This is due to what is known as trophic efficiency, or the 10% rule: basically, 10% of the energy at a lower level is present at the level right above it (level as in trophic level).

1. a tropical dry forest carries out more rapid nutrient cycling