Class 12th Biology 2018 Set1 Delhi Board Paper Solution
Explain the role of the ‘first trophic level’ in an ecosystem.
Ecological pyramid is given by Charles Elton in 1927 which is the graphical representation of the numbers or biomass and accumulated energy at each trophic level in the food chain. The base of the each pyramid represents the producers or first trophic level while the apex represents the next trophic levels like tertiary or high level consumers and other consumer trophic levels in between them.
first trophic level is the producer level like green plants (grasses) in the ecosystem which makes food on their own by the help of photosynthesis process. Producer level is important to because it is the key to the further trophic levels. The upper trophic levels are dependent on the first trophic level for the food and energy. Like Herbivores are the second trophic level which feeds on grasses (first trophic level) and then herbivores are eaten by the further trophic level organisms like carnivores and so on. So, they are interconnected.
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