When we talk about feeding relationships between organisms and energy transfer, we immediately remember the food chain. This chain, however, does not faithfully represent the flow of energy and nutrients in the ecosystem, which is better represented by the food webs.
→ What are food webs?
Food webs are nothing but several food chains connected. The webs are complex and show more faithfully how the flow of nutrients and energy takes place in an ecosystem, since there are no isolated chains in nature. In the case of food webs, the flow of energy and nutrients occurs in a multidirectional way.
→ What are trophic levels?
In a food web, the same organism can occupy different trophic levels
we call trophic level the group of individuals who have a diet based on practically the same nutrients. This means, for example, that herbivorous organisms are classified at the same trophic level.
Living beings are classified into three fundamental trophic levels: producers, consumers and decomposers.
Producers:
organisms autotrophic, that is, those who are able to produce their own food. Plants and algae are examples of producing organisms, as they produce their food through the process of photosynthesis.Consumers: those who need to eat to get the nutrients needed to carry out their activities, that is, they are heterotrophic. A consumer who feeds on a producer is called a primary consumer; on the other hand, the one who feeds on the primary consumer is called secondary consumer; what feeds from the secondary consumer is called tertiary and so on. It is worth noting that, as part of the energy is lost at each level, there is not a large amount of trophic levels.
Decomposers: In the group of decomposers, fungi and bacteria are included, which are related to the decomposition process. They are important because they promote the degradation of producers and consumers, releasing nutrients into the environment so they can return to biogeochemical cycles.
It is important to point out that an organism in a food chain can occupy only one trophic level, but, in the web, it can occupy different positions. Man, when eating a vegetable, for example, behaves like a primary consumer and, when eating a herbivore, behaves like a secondary consumer.
By Ma. Vanessa dos Santos
Source: Brazil School - https://brasilescola.uol.com.br/o-que-e/biologia/o-que-e-teia-alimentar.htm