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Types of Ecosystems

• Natural ecosystems operate under natural conditions.
• Based on habitat, natural ecosystems are classified into two types:
  • Terrestrial ecosystems are related to land (e.g., grasslands, forests, deserts).
  • Aquatic ecosystems are related to water.
• Aquatic ecosystems are further classified based on salt content:
  • Fresh water ecosystems:
    • Running water ecosystems (e.g., rivers, streams).
    • Standing water ecosystems (e.g., ponds, lakes).
  • Marine ecosystems (e.g., seas).
• Man-made or artificial ecosystems are operated or maintained by humans (e.g., croplands, gardens).

Function of Ecosystems

• Ecosystems have three main functions:
  • Primary function: The creation of carbohydrates through photosynthesis.
  • Secondary function: The distribution of energy in the form of food to consumers.
  • Tertiary function: The decomposition of dead organisms, initiating the recycling process within the ecosystem.

Understanding Ecosystem Functioning

• Energy and material flow.
• Food chains.
• Food webs.
• Ecological pyramids.

Energy Flow in Ecosystems

• Energy is essential for all living organisms.
• Solar energy is the primary energy source for Earth.
• Plants (producers) transform solar energy into chemical energy through photosynthesis.
• Some chemical energy is used by plants for growth, while the rest is transferred to consumers through consumption.

Components of Ecosystem Energy Flow (Diagram)

• Sun provides energy to producers.
• Producers convert energy into food.
• Consumers gain energy by consuming producers or other consumers.
• Decomposers break down dead organisms, returning nutrients to the ecosystem.

Food Chains

• A food chain is a sequence of organisms where each eats the one before it.
• Food chains start with a producer (plant).
• They end with a consumer (animal).
• When organisms die, decomposers break them down.
• Nutrients are then recycled, providing nutrients for the plants.
• About 80-90% of energy is lost as heat at each level.

Example of a Food Chain

• Grass → Grasshopper → Mouse → Owl

Food Webs

• A food web is a complex network of interconnected food chains.
• Multiple organisms at various trophic levels are involved.
• There are numerous opportunities for eating and being eaten.
• Herbivores eat plants and carnivores eat herbivores or other carnivores.

Example of Food Web

• Example: interconnections between various organisms (various animals and plants).