Set of all living beings that interact in a certain region and can be called biocenosis, community or of biota.
As we have seen, according to the way food is obtained, the community of an ecosystem is generally made up of three types of beings:
- Producers: the chemosynthesizing autotrophic beings (bacteria) and photosynthesizing beings (bacteria, algae and vegetables). The latter transform solar energy into chemical energy in the food produced.
- Primary Consumers: herbivorous beings, that is, that feed on producers (algae, plants, etc.), carnivores that feed on primary consumers (herbivores).
- There may still be tertiary consumers or quaternaries, which feed on secondary and tertiary consumers respectively.
- Decompositors: the bacteria and fungi that feed on the food remains of other living things. These organisms (many microscopic) have the important role of returning to the environment mineral nutrients that existed in these food debris and could thus be reused by producers.
In ecosystems, there is a flow of energy and nutrients as interconnected links in a chain, a food chain. In it, the “links” are called trophic levels and include producers, consumers (primary, secondary, tertiary, etc.) and decomposers.
In an aquatic ecosystem, such as a pond for example, we could establish the following sequence.
Composed of the margin and bottom plants of the lagoon and microscopic algae, which are mainly responsible for the oxygenation of the aquatic and terrestrial environment; This category of microscopic algae is called phytoplankton.
Composed of small floating animals (called Zooplankton), snails and herbivorous fish, all fed directly from the vegetables.
They are those that feed on the previous level, that is, carnivorous fish, insects, tortoises, etc.,
Waterfowl are the main component of this category, feeding on secondary consumers.
This category belongs neither to fauna nor flora, but feeds on their remains and is composed of fungi and bacteria.
View an example of aquatic ecosystem:
Already in a terrestrial ecosystem, we would have.
Formed by all photosynthetic components, which produce their own food (autotrophs) such as grass, weeds, lichens, shrubs, vines and trees;
These are all herbivores, which in the case of terrestrial ecosystems are insects, rodents, birds and ruminants;
They feed directly on primary consumers (herbivores). They are mainly formed by small carnivores;
These are larger consumers who feed on secondary consumers;
Here also as in the case of aquatic ecosystems, this category belongs neither to fauna nor flora and is composed of fungi and bacteria.