Ecological pyramid

This allows organisms on the lower levels to not only maintain a stable population, but also to transfer energy up the pyramid.

The exception to this generalization is when portions of a food web are supported by inputs of resources from outside the local community.

In small, forested streams, for example, the volume of higher levels is greater than could be supported by the local primary production.

However most wavelengths in solar radiation cannot be used for photosynthesis, so they are reflected back into space or absorbed elsewhere and converted to heat.

It is a graphical representation of biomass (total amount of living or organic matter in an ecosystem) present in unit area in different trophic levels.

For example, in a pond ecosystem, the standing crop of phytoplankton, the major producers, at any given point will be lower than the mass of the heterotrophs, such as fish and insects.

[4] The idea of the pyramid of productivity or energy relies on the works of G. Evelyn Hutchinson and Raymond Lindeman (1942).

The pyramid of energy represents how much energy, initially from the sun, is retained or stored in the form of new biomass at each trophic level in an ecosystem. Typically, about 10% of the energy is transferred from one trophic level to the next, thus preventing a large number of trophic levels. Energy pyramids are necessarily upright in healthy ecosystems, that is, there must always be more energy available at a given level of the pyramid to support the energy and biomass requirement of the next trophic level.
A pyramid of biomass shows the total biomass of the organisms involved at each trophic level of an ecosystem. These pyramids are not necessarily upright. There can be lower amounts of biomass at the bottom of the pyramid if the rate of primary production per unit biomass is high.
A pyramid of numbers shows the number of individual organisms involved at each trophic level in an ecosystem. The pyramids are not necessarily upright. In some ecosystems, there can be more primary consumers than producers.