Biosphere

Definition of Biosphere

The biosphere is the part of the Earth where life exists, including land (lithosphere), water (hydrosphere), and air (atmosphere). It extends from the deepest ocean trenches to the upper atmosphere where life can survive.

Components of the Biosphere

• Biotic components: All living organisms like plants, animals, fungi, and microorganisms.
• Abiotic components: Non-living elements such as soil, water, temperature, light, and minerals.

Major Life Zones in the Biosphere

• Lithosphere: The solid outer part of the Earth where organisms live (forests, deserts, grasslands).
• Hydrosphere: All the water bodies on Earth – oceans, rivers, lakes, groundwater.
• Atmosphere: The layer of gases surrounding the Earth that provides oxygen and carbon dioxide for life.

Ecological Concepts

• Ecology: The study of interactions between organisms and their environment.
• Ecosystem: A biological community of organisms along with their physical environment.
• Biome: A large community of plants and animals that occupies a distinct region.
• Biodiversity: The variety of life forms within a habitat or ecosystem.

Threats to the Biosphere

• Deforestation
• Pollution (air, water, soil)
• Climate change
• Loss of biodiversity
• Overexploitation of natural resources

Conservation Measures

• Afforestation and reforestation
• Protected areas like national parks and wildlife sanctuaries
• Reducing pollution and greenhouse gas emissions
• Promoting sustainable development

Previous Year Questions

• SSC CGL 2018: Which sphere of Earth supports life?
• Biosphere
• RRB NTPC 2019: What does the biosphere include?
• Land, water, and air supporting life
• SSC CHSL 2021: The study of the relationship between organisms and environment is called?
• Ecology
• HSSC CET 2022: What is an ecosystem?
• A community of organisms and their environment
• SSC JE 2017: Which of the following is a biotic component?
• Plants
• RRB ALP 2018: The area where living organisms are found is called?
• Biosphere
• SSC CGL 2020: Which one is not an abiotic factor?
• Bacteria
• SSC MTS 2022: What causes loss of biodiversity?
• Deforestation and pollution
• RRB Group D 2016: Which of the following supports aquatic life?
• Hydrosphere
• HSSC 2019: What is biodiversity?
• Variety of living organisms in an ecosystem
• SSC GD 2023: Which human activity causes maximum threat to biosphere?
• Deforestation
• SSC CPO 2019: Which zone includes all ecosystems of Earth?
• Biosphere
• SSC CHSL 2020: Which component is common to lithosphere, hydrosphere and atmosphere?
• Living organisms
• RRB JE 2019: What is a biome?
• A large natural area with distinct climate and organisms
• SSC MTS 2020: Biosphere reserve is meant to protect?
• Biological diversity
• SSC CGL 2022: Which gas is essential for respiration of living beings?
• Oxygen