Environmental Science Quiz

Environmental Science & Education

• Unit 1 covers the concept, importance, and components of the environment, ecosystems, ecosystem services, biodiversity, and environmental education/ethics.

• Unit 2 focuses on natural resources (renewable and non-renewable), natural resource management, and environmental pollution (air, water, soil pollution, solid waste management, and climate change).

• Suggested readings include various textbooks on environmental studies like Asthana, Basu, and Bharucha, as well as other relevant resources.

Environment: Concept, Importance, and Components

• The word "Environment" originates from the French word "environner," meaning to encircle or surround.

• Biologist Jacob Van Uerkal (1864-1944) introduced the term "environment" in Ecology.

• Environment is defined as the sum total of living and non-living components, influences, and events surrounding an organism.

• The Environment Protection Act of 1986 defines environment as the sum total of land, water, air, interrelationships among themselves and with human beings and other living organisms.

Ecology and Ecosystem

• Ecology is the study of the interactions of organisms with each other and their environment.

• Environmental Science is an interdisciplinary study of the interactions among physical, chemical, and biological components of the environment, with a focus on environmental pollution and degradation.

• It encompasses various subjects like biology, chemistry, physics, statistics, microbiology, biochemistry, geology, economics, law, and sociology.

• The narrow definition of environmental science is the study of human impact on the physical and biological environment of an organism.

Types of Environment Based on Human Interference

• Natural environment: Inherent, unaltered, and not manipulated by humans. Life processes and evolution are unhindered.

• Human-modified environment: A naturally occurring environment that has been modified to some extent by human intervention.

• Human-made environment: An environment deliberately controlled and converted by humans, such as cities, towns, crop fields, and artificial lakes/dams/industries.

Components of Environment

• Abiotic: light, humidity, water, temperature, atmospheric gases, altitude, latitude, and seasonal changes.

• Biotic: plants (flora), animals (fauna), human beings, parasites, and microorganisms.

• Energy: solar, geothermal, water, and nuclear energy.

Segments of the Environment

• Atmosphere, hydrosphere, lithosphere, and biosphere.

Structure of the Atmosphere

• The atmosphere is the layer of air surrounding the Earth.

• It's primarily composed of 79% nitrogen and 20% oxygen, with smaller amounts of other gases like carbon dioxide, water vapor, neon, helium, methane, krypton, hydrogen, and xenon.

• The atmosphere is layered: troposphere, stratosphere, mesosphere, thermosphere, and exosphere.

• Different layers have distinct characteristics related to weather, temperature, and atmospheric phenomena.

Hydrosphere

• A hydrosphere is the total amount of water on a planet, including surface water, groundwater, and water in the air.

• Water is crucial for life on Earth.

• A significant portion of Earth's water is saline (97%), while the rest is fresh water.

Lithosphere

• The rigid, rocky outer layer of the Earth.

• Consists of the crust and the solid outermost layer of the upper mantle.

• Different thicknesses in oceanic and continental crust.

Ecosystem Structure and Function

• Ecosystems are regions where living organisms interact with their environment.

• Abiotic components: Non-living factors (e.g., climate, soil, water, minerals).

• Biotic components: Living factors (e.g., plants, animals, microorganisms).

• Interconnected through interactions like feeding relationships (food chains/webs).

• Size and complexity vary dramatically, from a single tree to an entire rainforest.

• Ecosystem structure is created due to the interaction between abiotic and biotic components, and varies over space and time.

Ecosystem Services

• Benefits obtained from the regulation of ecosystem processes (air quality, climate, water, and erosion control, various other services discussed in the notes).

• These services are crucial to human well-being, impacting provisioning (food, water, etc.), regulating (climate, disease control), cultural (aesthetic and spiritual value), and supporting (nutrient cycling, water cycle) services.

Energy Flow in the Ecosystem

• Energy flows from the sun, through producers (plants), to consumers (herbivores, carnivores, omnivores) and decomposers.

• The process of photosynthesis converts solar energy into chemical energy (food for producers).

• Only about 10% of energy is transferred to the next trophic level in a food chain.

Food Chains, Food Webs, and Ecological Pyramids

• Food chains trace the flow of energy through the ecosystem.

• Food webs are complex networks of interconnected food chains.

• Ecological pyramids illustrate the relative amounts of organisms, energy, and biomass at different trophic levels.

Ecological Pyramids

• Three types of ecological pyramids are discussed - number, biomass, and energy. They show the relationship between biomass and trophic levels. Note: There are discussion points for inverted pyramid types.