Ecosystems

An ecosystem is a community of living organisms (biotic components) interacting with their non-living (abiotic) environment. These interactions form a system where energy and nutrients are transferred. The term "ecosystem" was first used by English botanist A.G. Tansley in 1935.

Understanding Ecosystems

Definition: A biological community of interacting organisms and their physical environment.
Interaction between Biotic and Abiotic Factors: The living and non-living components of an ecosystem interact with each other to create a stable system. Energy flows from one trophic level to the next, starting with the sun's energy captured by producers. Ecosystems also cycle essential nutrients between biotic and abiotic components.

Did You Know? The Earth is a closed system for matter (meaning all the atoms we have now are the same ones we've had for billions of years) but an open system for energy, as we constantly receive new energy from the Sun.

Biotic Components

Biotic components are the living parts of an ecosystem, such as plants, animals, and microorganisms. They are categorized by how they get nutrition:

Producers (or autotrophs): Organisms that produce their own food, usually through photosynthesis. Plants are a prime example.
Consumers (or heterotrophs): Organisms that obtain their food by eating other organisms. They can be primary consumers (herbivores), secondary consumers (carnivores or omnivores), or tertiary consumers.
Decomposers (or saprotrophs): Organisms that break down dead organic matter, such as bacteria and fungi.

Nature's Recyclers Decomposers are essential for the health of an ecosystem because they return nutrients from dead organisms back to the soil, where they can be used again by producers.

Food Chain, Food Web, and Pyramid of Numbers

Food Chain: A series of organisms in which each organism is the food of the next. Energy flows from one trophic level to the next.

Key Concept: The 10% Rule Only about 10% of the energy from one trophic level is passed on to the next. The remaining 90% is lost as heat during metabolic processes (like respiration) or used for the organism's growth.

Food Web: A system of interconnected food chains, showing the complex feeding relationships in an ecosystem.
Pyramid of Numbers: A graphical representation of the number of organisms at each trophic level in a food chain. It shows that the number of organisms decreases as you go up the food chain.

Interdependence between Organisms

Symbiosis: A close and long-term interaction between two different biological species.
Parasitism: A relationship between two organisms in which one organism, the parasite, benefits at the expense of the other, the host.
Predation: A biological interaction where one organism, the predator, kills and eats another organism, its prey.

Abiotic Components

Abiotic components are the non-living chemical and physical parts of an ecosystem.

Air: The mixture of gases that surrounds the Earth.
Soil: The upper layer of earth in which plants grow, providing nutrients and support.
Water: A colorless, transparent, odorless, tasteless liquid that forms the seas, lakes, rivers, and rain and is the basis of the fluids of living organisms.
Climatic Factors:
- Sunlight: The primary source of energy for most ecosystems.
- Temperature: The degree or intensity of heat present in a substance or object, which affects the rate of metabolism reactions.
- Humidity: The amount of water vapor in the air.
- Wind: The perceptible natural movement of the air, which can affect temperature and humidity.

Types of Ecosystems

Ecosystems are broadly categorized into two types:

Terrestrial Ecosystems: These are land-based ecosystems.
- Forest Ecosystems: Dominated by trees, these are vital for biodiversity.
- Grassland Ecosystems: Characterized by vast open spaces of grass.
- Desert Ecosystems: Very dry and often hot environments.
- Tundra Ecosystems: Cold, windy, and with little rainfall.
Aquatic Ecosystems: These are water-based ecosystems.
- Freshwater Ecosystems: Include rivers, lakes, and wetlands.
- Marine Ecosystems: Include oceans and coral reefs.

Forest Ecosystem

Flora: The plants of a particular region, habitat, or geological period.
Fauna: The animals of a particular region, habitat, or geological period.

Check Your Knowledge

Which organisms are known as 'nature's recyclers' for breaking down dead organic matter?

What is a system of interconnected food chains called?

Ecosystems

Understanding Ecosystems

Definition: A biological community of interacting organisms and their physical environment.
Interaction between Biotic and Abiotic Factors: The living and non-living components of an ecosystem interact with each other to create a stable system. Energy flows from one trophic level to the next, starting with the sun's energy captured by producers. Ecosystems also cycle essential nutrients between biotic and abiotic components.

Biotic Components

Biotic components are the living parts of an ecosystem, such as plants, animals, and microorganisms. They are categorized by how they get nutrition:

Producers (or autotrophs): Organisms that produce their own food, usually through photosynthesis. Plants are a prime example.
Consumers (or heterotrophs): Organisms that obtain their food by eating other organisms. They can be primary consumers (herbivores), secondary consumers (carnivores or omnivores), or tertiary consumers.
Decomposers (or saprotrophs): Organisms that break down dead organic matter, such as bacteria and fungi.

Nature's Recyclers Decomposers are essential for the health of an ecosystem because they return nutrients from dead organisms back to the soil, where they can be used again by producers.

Food Chain, Food Web, and Pyramid of Numbers

Food Chain: A series of organisms in which each organism is the food of the next. Energy flows from one trophic level to the next.

Food Web: A system of interconnected food chains, showing the complex feeding relationships in an ecosystem.
Pyramid of Numbers: A graphical representation of the number of organisms at each trophic level in a food chain. It shows that the number of organisms decreases as you go up the food chain.

Interdependence between Organisms

Symbiosis: A close and long-term interaction between two different biological species.
Parasitism: A relationship between two organisms in which one organism, the parasite, benefits at the expense of the other, the host.
Predation: A biological interaction where one organism, the predator, kills and eats another organism, its prey.

Abiotic Components

Abiotic components are the non-living chemical and physical parts of an ecosystem.

Air: The mixture of gases that surrounds the Earth.
Soil: The upper layer of earth in which plants grow, providing nutrients and support.
Water: A colorless, transparent, odorless, tasteless liquid that forms the seas, lakes, rivers, and rain and is the basis of the fluids of living organisms.
Climatic Factors:
- Sunlight: The primary source of energy for most ecosystems.
- Temperature: The degree or intensity of heat present in a substance or object, which affects the rate of metabolism reactions.
- Humidity: The amount of water vapor in the air.
- Wind: The perceptible natural movement of the air, which can affect temperature and humidity.

Types of Ecosystems

Ecosystems are broadly categorized into two types:

Terrestrial Ecosystems: These are land-based ecosystems.
- Forest Ecosystems: Dominated by trees, these are vital for biodiversity.
- Grassland Ecosystems: Characterized by vast open spaces of grass.
- Desert Ecosystems: Very dry and often hot environments.
- Tundra Ecosystems: Cold, windy, and with little rainfall.
Aquatic Ecosystems: These are water-based ecosystems.
- Freshwater Ecosystems: Include rivers, lakes, and wetlands.
- Marine Ecosystems: Include oceans and coral reefs.

Forest Ecosystem

Flora: The plants of a particular region, habitat, or geological period.
Fauna: The animals of a particular region, habitat, or geological period.

Ecosystems

Ecosystems

Understanding Ecosystems

Biotic Components

Food Chain, Food Web, and Pyramid of Numbers

Interdependence between Organisms

Abiotic Components

Types of Ecosystems

Forest Ecosystem

Check Your Knowledge

Which organisms are known as 'nature's recyclers' for breaking down dead organic matter?

What is a system of interconnected food chains called?

On this page

Ecosystems

Ecosystems

Understanding Ecosystems

Biotic Components

Food Chain, Food Web, and Pyramid of Numbers

Interdependence between Organisms

Abiotic Components

Types of Ecosystems

Forest Ecosystem

Check Your Knowledge

Which organisms are known as 'nature's recyclers' for breaking down dead organic matter?

What is a system of interconnected food chains called?

On this page