How are trophic levels related to the flow of energy through an ecosystem?
The energy in an ecosystem flows form a lower trophic level to a higher tropic level generally in a 10% ratio.
The second trophic level is that of herbivores or first level consumers. These organisms get their energy from eating plants or producers. It takes approximately 10 kg of organic mass at the producer trophic level to support 1 kg of organic mass at the first level consumer level. Another way of saying this is that roughly 10% of energy available at the previous level is available to the organism the next trophic level up.
The energy continues to flow upward from the first level consumer level to the second level consumer level. Second level consumer are carnivores that get their energy from eating first level consumers. Again there is a 10% amount of the energy that flows upwards from the first level to the second level.
There are carnivores that operates at the third, fourth and even fifth levels of energy. These are sometimes called top carnivores.