6 LEVELS OF ECOLOGICAL ORGANIZATION: WHAT AND WHAT ARE THEY? - BIOLOGY - 2024

The levels of ecological organization are individual, population, community, ecosystem, biosphere, and biome. They describe the disposition of biological organisms in relation to each other, being a classification and organization of the various ecosystems.

These ecosystems can be studied at small or large levels. At the simplest level of the hierarchy are individual organisms, where interactions with other organisms are not considered.

Moving up the hierarchy, ecologists have found more complex ways of describing relationships between organisms. These culminate in the biosphere, which describes the totality of all living things on planet Earth.

Levels of ecological organization

1- Individuals or organisms

Individuals or organisms constitute the basic unit of study in ecology. At each level, the biological unit has a specific structure and function.

At this level, form, physiology, behavior, distribution, and adaptations are studied in relation to environmental conditions.

Similar organisms or individuals have the potential to interbreed and produce fertile offspring (later called species). The organism or individual carries out all its life processes independently.

An individual or organism is fully adapted to its environment. It has a defined life span that includes stages such as birth, hatching, growth, maturity, senescence, aging, and death. Competition, mutualism, and predation are various types of interaction between organisms.

Aspects of evolution are widely used in the study of this level. At this level, ecology is concerned with the biological, morphological, and physiological development of individual organisms in response to their natural environment.

2- Population

Pack of wolves.

An ecological population is made up of a group of individuals of a given species that live in a specific geographic area at a given time and that function as a unit of biotic community.

Populations include individuals of the same species, but they may have different genetic characteristics such as hair, eye, and skin color and size between themselves and other populations.

For example, individuals of elephants or tigers in an area constitute a population. Generally, interactions between populations are studied. These interactions can be those of a predator and its prey, or a parasite with its host.

Competition, mutualism, commensalism, parasitism, and predation are various types of interactions.

3- Community

Communities include all populations in a specific area at any given time. A community includes populations of organisms of different species. For example, populations of fish, salmon, crabs and herring coexist in a defined place forming an ecological community.

Biotic community organization results from the interdependence and interactions between populations of different species in a habitat. It is a set of populations of plants, animals, bacteria and fungi that live in an area and interact with each other.

A biotic community has a composition and structure of distinct species such as animals, plants, and decomposers (that is, bacteria and fungi).

4- Ecosystem

Ecosystems as part of nature are the place where living organisms interact with each other and with their physical environment.

An ecosystem is composed of a biotic community, integrated with its physical environment through the exchange of energy and recycling of nutrients.

Ecosystems can be recognized as self-regulating and self-sufficient units of the biome, such as a pond or a forest.

An ecosystem has two basic components: abiotic (non-living) and biotic (living organisms). Abiotic components comprise inorganic materials such as carbon, nitrogen, oxygen, CO2, water, etc., while biotic components include producers, consumers, and decomposers.

5- Biome

A biome, in simple terms, is a set of ecosystems that share similar characteristics with their abiotic factors adapted to their environment.

Biomes are units of land with a natural boundary that have a mosaic of terrains that generally represent different ecosystems.

It is a large regional unit characterized by an important type of vegetation and associated fauna found in a specific climatic zone.

The biome includes all associated developing and modified communities that occur within the same climatic region, for example forest biomes, grassland and savanna biomes, desert biome, etc.

On a global scale, all terrestrial biomes and aquatic systems on Earth make up the biosphere.

6- Biosphere

When we consider all the different biomes, each mixed into the other, with all human beings living in many different geographic areas, we form a huge community of humans, animals, plants, and microorganisms in their defined habitats.

A biosphere is the sum of all the ecosystems established on planet Earth. It is the living (and decaying) component of the Earth system.

The entire inhabited part of the earth and its atmosphere, including living components, are called the biosphere. The global environment consists of three main subdivisions:

• the hydrosphere that includes all the components of water
• the lithosphere that comprises the solid components of the earth's crust
• the atmosphere formed by the earth's ozone layer.

The biosphere consists of the lower atmosphere, the land, and the oceans, rivers, and lakes, where living things are found.

By default, the biosphere includes climate, geology, oceans, and human pollution. This level of analysis may seem abstract, but it often has practical applications.

Global climate change, for example, examines how the destruction of an ecosystem - for example the Amazon rainforest - can lead to a loss of global climate regulation and affect life in a part of the Earth distant from the Amazon.

References

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