What are ecological pyramids? Name and explain their limitations.
The different trophic levels of an ecosystem are related to one another and hence can be represented in the form of pyramid in which the base is broad and it narrows to a point at the top. The dare of each pyramid represents the producers or the first trophic level, while the apex represents tertiary or high level consumers.
Various ecological pyramids are:
- Pyramid of Numbers: It is the graphic representation of total number of individuals of different species belonging to each trophic level in an ecosystem is known as pyramid of numbers.
- Pyramid of Biomass: Diagrammatic representation of biomass of individuals belonging to the different trophic levels invariably assumes the shape of an upright pyramid.
- Pyramid of Energy: It represents the rate of passage of energy through the food chain.
Limitations of ecological pyramids:
- Individuals which feed at more than one trophic level are extremely difficult to depict in ecological pyramid
- Saprophytes are not represented in ecological pyramid, although play important role.
- Seasonal and diusinal variations are not depicted by these pyramids.
- Human waste, litter etc. although play important role but not included in the pyramid.