Question

If 1,000J of energy is available to maize plants from the sun, how much energy will be available to eagle in the food chain comprising eagle, snake, mice, and maize plants?

Answer 1

The food chain:

• This represents the flow of energy or the sequence in which organisms consume one another in an ecosystem.
• For the given sequence of consumption, the following food chain will be present in an ecosystem:

Maize→Mice→Snake→Eagle

T1→T2→T3→T4

Ten percent law:

• According to this law, each trophic level utilizes 90% of the energy and only 10% of the energy is available for the next trophic level.
• Therefore, the producers like maize (plant) will provide only 10% of the energy (1,000J) to the mice (trophic level2).
• As the trophic level increases, the energy keeps reducing since each trophic level or organism loses energy in the form of heat and in the process of performing several life processes.

The energy available to mice (T2):

$\begin{array}{rcl}T2& =& \frac{T1}{10}\\ & =& \frac{1000}{10}\\ & =& 100J\end{array}$

Similarly, for, snake (T3), energy will be

$\begin{array}{rcl}T3& =& \frac{T2}{10}\\ & =& \frac{100}{10}\\ & =& 10J\end{array}$

Hence, The energy available to eagle (T2):

$\begin{array}{rcl}T4& =& \frac{T3}{10}\\ & =& \frac{1}{10}\\ & =& 0.1J\end{array}$

The energy available to the eagle is 0.1J.