Understanding the Biosphere and Ecosystems on Earth

Understanding the Biosphere

The set of all living beings that inhabit the Earth is known as the biosphere. Currently, there are approximately 2 million species. An ecosystem is defined as all living beings that inhabit a specific place, where relationships are established between them and the physical environment they live in, along with the site characteristics and relationships between the environment and organisms.

Types of Ecosystems

There are several types of ecosystems:

• Aquatic Ecosystems: Rivers, ponds
• Terrestrial Ecosystems: Deserts, forests

The Ecosphere

The ecosphere is the set of all the ecosystems of our planet. The biosphere is the living part of the food ecosystem, where living beings perform vital functions. All living things need energy, which is derived from nutrients in food.

Classification of Living Beings

Living beings are classified into:

• Producers: Organisms that make their own organic material, such as plants and algae.
• Consumers: Organisms that eat other living things:
  • Primary Consumers: Herbivores that feed on plants.
  • Secondary Consumers: Carnivores that feed on herbivores.
  • Tertiary Consumers: Animals that eat other animals and can be herbivores or carnivores.
• Decomposers: Organisms that feed on decomposing matter.

Trophic Levels

The relationships between living things are represented in trophic pyramids, which graphically illustrate the variation between trophic levels for a specific feature. Each level represents the energy stored in one trophic level. The flow of energy in the ecosystem begins with light energy, which is transformed into chemical energy by photosynthetic organisms. This energy is stored in the organic matter of producers and passes from one trophic level to another.

Energy Flow and Matter Cycle

As energy flows through different trophic levels, it is a unidirectional flow; only 10% of energy is available to the next level. The cycle of matter ensures that energy is recycled. When producers and consumers die, their remains are converted into inorganic matter by decomposers.

Biotic Relationships

Biotic relationships can be categorized as follows:

• Intraspecific Associations: Groups of living individuals that interact for a longer or shorter time to mutually benefit each other.
• Social Associations: Distribution of related individuals working together.
• Family Associations: Groups that focus on procreation and protection of offspring.
• Interspecific Relationships: Mutualism, where two or more individuals of different species benefit mutually.
• Commensalism: One individual benefits from food debris released by another, while the other remains indifferent.
• Parasitism: One individual lives off another, causing damage without killing it.
• Predation: One organism consumes all or part of another to feed.