Introduction to Environment and Ecosystems

Introduction to Environment

• Environment encompasses the surroundings of an organism, including both living (biotic) and non-living (abiotic) factors.
• This chapter explores the components of the environment, their interactions, and how human activities influence it.

Ecosystems

• An ecosystem comprises all biotic (living) and abiotic (non-living) factors interacting within a specific area.
• Biotic factors include plants, animals, microorganisms, and humans. Abiotic factors include sunlight, temperature, air, wind, rainfall, soil, and minerals.
• Examples of ecosystems include pond ecosystems and grassland ecosystems.

Biotic and Abiotic Factors

• Biotic factors : Living organisms within the ecosystem.
• Abiotic factors : Non-living chemical and physical components, such as soil, air, water, temperature, sunlight.

Trophic Levels

• Trophic levels represent the different feeding positions (or levels) in an ecosystem’s food web.
• Producers (T1): Organisms that make their own food (plants).
• Primary Consumers (Herbivores - T2): Organisms that eat producers.
• Secondary Consumers (Primary Carnivores - T2): Organisms that eat primary consumers.
• Tertiary Consumers (Secondary Carnivores - T3): Organisms that eat secondary consumers.
• Quaternary Consumers (Tertiary Carnivores - T4): Organisms that eat tertiary consumers.
• Decomposers: Break down organic matter and release nutrients.

Mode of Nutrition

• Two types of nutrition exist in living organisms:
• Autotrophic: Organisms that make their own food (plants, some bacteria).
• Heterotrophic: Organisms that obtain food from other organisms (animals, fungi, some bacteria)

Saprophytes and Decomposers

• Saprophytes: Organisms that feed on dead and decaying matter (fungi, some microorganisms). They absorb nutrients from the decaying matter.
• Decomposers: Organisms that break down complex organic matter into simpler substances, releasing nutrients back into the soil (bacteria, worms, slugs).

Food Chains and Food Webs

• Food Chain: A linear sequence of organisms in which each organism feeds on the one below it.
  • Example: Producer -> Primary Consumer -> Secondary Consumer.
• Food Web: Interconnected food chains showing multiple feeding relationships in an ecosystem.
  • More complex than food chains, showing who eats whom.

Pollution

• Pollution involves the introduction of harmful substances (pollutants) into the environment.
• Types include air, water, soil, and noise pollution, often stemming from natural causes or human activities.
• Ozone layer depletion is a concern due to human-made chemicals (CFCs) reacting with ozone molecules in the atmosphere.

Waste Disposal

• Methods of waste disposal include landfills, incineration, waste compaction, biogas generation, composting, and vermicomposting.

Biodegradable Waste

• Biodegradable waste originates from plant or animal sources. It's decomposed by natural processes.

Biodegradation

• Biodegradation is the decomposition of waste or garbage by living organisms.

Pyramid of Trophic Levels

• Pyramid of numbers: Represents the number of organisms at each tropic level.
• Pyramid of biomass: Shows the total biomass of organisms at each tropic level.
• Pyramid of energy: Always upright, showing the flow of energy from one level to the next. Only about 10% of energy is transferred from one trophic level to the next.
• The pyramids depict the flow of energy and biomass through trophic levels.

Law of Conservation of Energy

• Energy cannot be created or destroyed; it can only change form.
• In biological systems, energy gets transferred from one organism to another.

This quiz covers the essential concepts of environment, ecosystems, and the interactions between biotic and abiotic factors. Explore the roles of various organisms and understand the significance of trophic levels in ecological systems. Test your knowledge on how human activities impact these components.