• What is an ecosystem?
• Components of an ecosystem
• Ecosystem types
• Characteristics of an ecosystem
• Ecosystem examples

We explain what ecosystems are and what types exist. In addition, how they are composed, their characteristics and various examples.

There is a great diversity of ecosystems on the planet.

What is an ecosystem?

In biology, an ecosystem is a system which is made up of a set of organisms, the environment physical in which they live (habitat) and the biotic and abiotic relationships that are established between them. The species from living beings that inhabit a certain ecosystem interact with each other and with the environment, determining the flow of Energy and of matter what happens in that environment.

There is a great diversity of ecosystems on the planet. They are all made up of biotic factors (living beings) and abiotic factors (non-living elements, such as I usually or the air). There are also different types of ecosystems: there are marine, terrestrial, microbial and artificial, among other examples.

An example of the relationships that take place between living things in an ecosystem are food relationships. The Trophic chains or food They are simple representations of the food relationships that exist between the species that are part of a given ecosystem. In general, in ecosystems, food chains interrelate, forming trophic webs.

It is said that there is a trophic relationship between two organisms when one of them is consumed by the other. In turn, the consuming organism may be the food from another that is part of the same ecosystem. Thus, a connection is formed between several links and a food chain is formed. Each link in a chain represents an organism that "eats another" or "is eaten by another."

Within food chains there are different trophic levels, which are based on the position that an organism occupies in the flow of matter and energy. In other words, the trophic level groups together all the species that share the origin of their food within the ecosystem. There are three trophic levels:

• Producers. Are autotrophic organisms, that is, they are capable of producing organic material (their own food) from inorganic material, through photosynthesis or chemosynthesis. Producers are the first trophic level, that is, they constitute the first link in food chains. This group is represented by the plants, algae and phytoplankton and some bacteria.
• Consumers. Are heterotrophic organisms, that is, they feed on other living beings to obtain the matter and energy they need. In turn, consumers are classified into different groups, according to the organism that constitutes their food. The primary consumers are the organisms herbivores, that is, those that feed on producers. Secondary consumers, for their part, are carnivores and they feed on primary consumers. There are also tertiary and quaternary consumers, which feed on secondary and tertiary consumers respectively.
• Decomposers. They are organisms that feed on decomposing organic matter, that is, they obtain the matter and energy they need from the remains of other living beings. Although they are not usually represented in food chains, they are fundamental in the nature since they allow the recycling of nutrients. Decomposing organisms include mushrooms, the worms and some bacteria that recycle organic matter.

The concept of ecosystem should not be confused with that of biome. A biome is an area o geographic region of planet Earth characterized by its weather, topography Y biodiversity. Unlike ecosystems, biomes are considered homogeneous geographic units. The same biome can contain several ecosystems.

Currently, many ecosystems are in risk due to human industrial activity. The pollution, the overexploitation, the deforestation and the effects of climate change often involve extinctions, overpopulations, mutations Y displacements that threaten biodiversity and natural balance.

Components of an ecosystem

An ecosystem is made up of two types of elements or factors:

• Biotic elements. They are those elements of an ecosystem that have life, that is, all the living beings that inhabit it.For example: Flora and fauna.
• Abiotic elements. They are those lifeless factors that are part of an ecosystem. For example: weather conditions, relief, variation of pH, presence of sunlight.

It is very important to bear in mind that the relationships established between the biotic and abiotic elements are also considered one more element that forms a specific ecosystem.

Ecosystem types

Mixed ecosystems combine aquatic and terrestrial environments.

There are different types of ecosystems that are classified according to the habitat in which they are located:

• Aquatic ecosystems. They are characterized by the presence of Water as the main component and they are the most abundant type of ecosystem: they constitute almost 75% of all known ecosystems. This group includes the ecosystems of the oceans and those of fresh or salty continental waters, such as rivers, lakes and lagoons.
• Terrestrial ecosystems. They take place on the Earth crust and out of the water in various types of relief: moutains, plains, valleys, deserts. There are important differences between them temperature, oxygen concentration and weather, so the biodiversity of these ecosystems is great and varied. Some examples of this type of ecosystems are the woods, the bushes, the steppe and the deserts.
• Mixed ecosystems. They are ecosystems that are located in areas of "intersection" of different types of land, for example, in which the aquatic and terrestrial environments are combined. Mixed ecosystems, also called hybrids, share characteristics of both terrestrial and aquatic ecosystems, and are considered transition zones between both types of ecosystems mentioned. The living beings that inhabit this type of ecosystem (such as the amphibians) spend most of their time in one of the two ecosystems but require the other to rest, feed or procreate. Some examples of this type of ecosystem are mangroves, estuaries and coasts.
• Microbial ecosystems. They are ecosystems formed by microscopic organisms that inhabit practically all environments, both aquatic and terrestrial, and even within larger organisms, such as the intestinal microbial flora.
• Artificial ecosystems. They are those ecosystems created and / or intervened by the human being, for which they are also known as anthropic ecosystems. Some examples of these ecosystems, which are increasingly common on our planet, are urban ecosystems, reservoirs and agricultural ecosystems.

Characteristics of an ecosystem

Multiple interactions such as food chains occur in each ecosystem.

• They are formed by biotic and abiotic factors that are dynamically interrelated through trophic chains, that is, the flow of matter and energy.
• They vary in size and structure depending on their type.
• They can be terrestrial (in reliefs As the desert, the Mountain, the Meadow), aquatic (fresh or salt water) or mixed (such as those found in wetlands).
• They can be natural or artificial (created and / or intervened by humans)
• There is a great biodiversity in many of them.
• They are dynamic and variable environments that experience natural or artificial changes and a constant flow of energy and nutrients between the factors (both biotic and abiotic) that constitute them. The “ecotone” is the transition zone between one ecosystem and another.
• The main source of energy in ecosystems is that which comes from solar radiation. This energy is used by the producers (who are the first trophic level of the food chains) to fix the inorganic matter in organic.
• They are complex systems due to the interactions between their members. The greater the biodiversity, the greater the complexity of the ecosystem.
• They can be altered naturally (such as natural disasters) or by the action of man (such as deforestation, the pollution and indiscriminate fishing). Alterations by human action can cause irreversible damage to ecosystems, since many times the species that inhabit there cannot adapt to the changes produced in the environment.
• They are studied by the ecology, branch of biology that studies living beings and their relationship with the environment they inhabit.

Ecosystem examples

Coral reefs present a great concentration of life and biodiversity.

• Coral reefs. They are one of the largest concentrations of life in the underwater world and occur in and around the coral structures that form a natural barrier. Due to the abundance of organic matter that lives in them, numerous species of fish, crustaceans and small mollusks serve, in turn, as food for predators.
• Underwater abyssal zones. They are extreme ecosystems, with little animal presence and no plant presence, since the absence of sunlight prevents photosynthesis. The living organisms that inhabit there adapt to the enormous pressure of the water and the low amount of nutrients.
• Polar ecosystems. They are ecosystems that are characterized by temperatures very low and little humidity atmospheric. Despite this, they have a sea rich in plankton and an animal life adapted to icy waters: the animals have hairy bodies and dense layers of fat.
• Lotus ecosystems. They take place in and on the banks of rivers, streams, or springs on the earth's surface. Life in them adapts to the flow of water, which carries nutrients, chemicals, living species or highly oxygenated water with it. movement.