evs_complete_short_notes_watermark (1).pdf
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Environmental Science - Complete Notes Unit 1: Environment Basics & Sustainability (6 Hours) Basic Concepts of Environment Definition of Environment • Sum total of physical, chemical, biological factors affecting living organisms • Includes biotic (living) and abiotic (non-living) components • Dynamic system with continuous interactions Components of Environment • Lithosphere: Earth's crust and soil • Hydrosphere: Water bodies • Atmosphere: Air and gases • Biosphere: Living organisms Ecosystem Fundamentals Ecosystem Definition & Types Ecosystem: Functional unit where living organisms interact with physical environment Natural Ecosystems: - Forest ecosystems - Grassland ecosystems - Desert ecosystems - Aquatic ecosystems Artificial Ecosystems: - Agricultural fields - Gardens - Parks - Aquariums Ecosystem Services: - Provisioning - Regulating - Cultural - Supporting Society-Environment Relationships Human Impact on Environment • Population Growth: Exponential increase leading to resource depletion • Urbanization: Land use changes, habitat loss • Industrialization: Pollution, waste generation • Agriculture: Soil degradation, pesticide use Environmental Determinism • Environment shapes human activities and culture • Climate influences lifestyle and development • Natural resources determine economic activities • Geographic factors affect settlement patterns Sustainable Development Principles of Sustainability Environmental Sustainability: - Resource conservation - Pollution prevention - Biodiversity protection - Ecosystem maintenance Economic Sustainability: - Long-term economic growth - Resource efficiency - Green technology - Circular economy Social Sustainability: - Equity and justice - Community participation - Cultural preservation - Quality of life Unit 2: Ecology & Ecosystems (6 Hours) Elements of Ecology Ecological Concepts • Ecology: Study of relationships between organisms and environment • Habitat: Physical environment where organism lives • Niche: Functional role of organism in ecosystem • Population: Same species in given area • Community: Different populations living together Ecological Factors • Abiotic Factors: Temperature, light, water, soil, pH • Biotic Factors: Competition, predation, parasitism • Limiting Factors: Factors that limit population growth • Law of Minimum: Growth limited by scarcest resource Ecosystem Structure & Function System Concepts Inputs: - Solar energy - Nutrients - Water - Carbon dioxide Processes: - Photosynthesis - Respiration - Decomposition - Nutrient cycling Outputs: - Heat energy - Biomass - Waste products - Oxygen Environmental Hazards & Management Natural Hazards • Floods: Excessive water overflow • Earthquakes: Ground shaking due to tectonic movement • Droughts: Prolonged water scarcity • Cyclones: Violent wind storms • Landslides: Downward movement of rock and soil Management Strategies • Prevention: Land use planning, building codes • Preparedness: Early warning systems, evacuation plans • Response: Emergency services, rescue operations • Recovery: Rehabilitation, reconstruction • Mitigation: Risk reduction measures Unit 3: Ecosystem Components & Biodiversity (11 Hours) Ecosystem Components Producers (Autotrophs) • Green plants and algae • Convert sunlight to chemical energy • Primary productivity • Gross Primary Productivity (GPP) • Net Primary Productivity (NPP) Consumers (Heterotrophs) • Primary: Herbivores (plant eaters) • Secondary: Carnivores (meat eaters) • Tertiary: Top carnivores • Omnivores: Plant and meat eaters Decomposers • Bacteria and fungi • Break down dead organic matter • Nutrient recycling • Detritus food chain Types of Ecosystems Terrestrial Ecosystems • Forest: High biodiversity, complex structure • Grassland: Dominated by grasses • Desert: Low precipitation, adapted organisms • Tundra: Cold climate, permafrost • Mountain: Altitude gradients, varied zones Aquatic Ecosystems • Freshwater: Rivers, lakes, ponds, streams • Marine: Oceans, seas, coral reefs • Estuarine: Where rivers meet sea • Wetlands: Marshes, swamps, bogs Energy Flow & Food Relations Food Chains & Food Webs Food Chain: - Linear sequence of energy transfer - Producer → Primary Consumer → Secondary Consumer - Usually 3-4 trophic levels - 10% energy transfer efficiency Food Web: - Complex network of food chains - Multiple feeding relationships - More stable than food chains - Represents real ecosystem complexity Biogeochemical Cycles Carbon Cycle • Photosynthesis removes CO₂ from atmosphere • Respiration releases CO₂ • Ocean carbon storage • Fossil fuel burning increases atmospheric CO₂ Nitrogen Cycle • Nitrogen fixation by bacteria • Nitrification and denitrification • Plant uptake of nitrates • Decomposition returns nitrogen to soil Water Cycle • Evaporation from water bodies • Transpiration from plants • Condensation and precipitation • Infiltration and runoff Phosphorus Cycle • No atmospheric component • Weathering of rocks releases phosphorus • Plant uptake from soil • Returns through decomposition Biodiversity Levels of Biodiversity Genetic Diversity: - Variation within species - Gene pool diversity - Adaptation potential - Disease resistance Species Diversity: - Number of species - Species richness - Species evenness - Endemic species Ecosystem Diversity: - Variety of habitats - Different communities - Landscape diversity - Functional diversity Unit 4: Atmospheric Layers & Global Issues (10 Hours) Atmospheric Layers Structure of Atmosphere • Troposphere (0-12 km): Weather phenomena, decreasing temperature • Stratosphere (12-50 km): Ozone layer, increasing temperature • Mesosphere (50-80 km): Meteors burn up, decreasing temperature • Thermosphere (80-600 km): High temperature, aurora • Exosphere (>600 km): Transition to space Atmospheric Composition • Nitrogen (78%): Inert gas, protein component • Oxygen (21%): Essential for respiration • Argon (0.93%): Noble gas • Carbon dioxide (0.04%): Greenhouse gas • Trace gases: Methane, ozone, water vapor Global Environmental Issues Global Warming & Climate Change Causes: - Greenhouse gas emissions - Fossil fuel burning - Deforestation - Industrial activities - Agriculture (methane) Effects: - Rising global temperatures - Sea level rise - Extreme weather events - Ecosystem disruption - Species extinction Ozone Layer Depletion Ozone Depletion Process • CFCs (Chlorofluorocarbons): Main ozone depleting substances • UV radiation: Breaks down CFCs releasing chlorine • Catalytic destruction: One chlorine destroys many ozone molecules • Ozone hole: Severe depletion over Antarctica Consequences & Solutions • Effects: Increased UV radiation, skin cancer, cataracts • Montreal Protocol: International agreement to phase out CFCs • Alternatives: HCFCs, HFCs (less ozone depleting) • Recovery: Ozone layer slowly healing Environmental Impact Assessment (EIA) EIA Process & Case Studies EIA Steps: - Screening - Scoping - Impact assessment - Mitigation measures - Monitoring Assessment Areas: - Air quality - Water resources - Soil and geology - Flora and fauna - Socio-economic impacts Case Studies: - Large dams - Mining projects - Industrial complexes - Highway construction - Power plants Unit 5: Waste Management (3 Hours) Solid Waste Management Types of Solid Waste • Municipal Solid Waste: Household, commercial waste • Industrial Waste: Manufacturing byproducts • Hazardous Waste: Toxic, flammable, corrosive materials • Biomedical Waste: Hospital, clinical waste • E-waste: Electronic components, devices Waste Management Hierarchy • Reduce: Minimize waste generation • Reuse: Use items multiple times • Recycle: Convert waste into new products • Recovery: Energy recovery from waste • Disposal: Safe disposal as last option Waste Treatment Technologies Modern Treatment Methods Physical Treatment: - Sorting and segregation - Shredding and crushing - Magnetic separation - Screening Biological Treatment: - Composting - Anaerobic digestion - Vermicomposting - Bioremediation Thermal Treatment: - Incineration - Pyrolysis - Gasification - Plasma arc Pollution Control Technologies Air Pollution Control • Electrostatic Precipitators: Remove particulates • Scrubbers: Remove gases and particles • Catalytic Converters: Reduce vehicle emissions • Fabric Filters: Baghouse filtration Water Pollution Control • Primary Treatment: Physical removal of solids • Secondary Treatment: Biological treatment • Tertiary Treatment: Advanced purification • Membrane Technology: RO, ultrafiltration Unit 6: Environmental Policies & Legislation (3 Hours) National Environmental Policies Indian Environmental Acts • Environment Protection Act (1986): Umbrella legislation • Water (Prevention & Control of Pollution) Act (1974): Water quality • Air (Prevention & Control of Pollution) Act (1981): Air quality • Wildlife Protection Act (1972): Biodiversity conservation • Forest Conservation Act (1980): Forest protection Pollution Control Boards • Central Pollution Control Board (CPCB): National level • State Pollution Control Boards (SPCB): State level • Functions: Monitoring, enforcement, standards • Powers: Issue consent, prosecution, closure Conservation Movements Major Environmental Movements in India Forest Conservation: - Chipko Movement (Himalaya) - Appiko Movement (Western Ghats) - Silent Valley Movement (Kerala) - Forest rights movements Water & Land Conservation: - Narmada Bachao Andolan - Tehri Dam opposition - Rainwater harvesting initiatives - Watershed management International Environmental Treaties Global Environmental Agreements Climate Change: - UNFCCC (1992): Framework convention - Kyoto Protocol (1997): Emission targets - Paris Agreement (2015): Global warming limit - COP meetings: Annual climate conferences Other Major Treaties: - Montreal Protocol: Ozone protection - CITES: Endangered species trade - Basel Convention: Hazardous waste - Convention on Biological Diversity Important Formulas & Key Points Key Formulas • Primary Productivity: NPP = GPP - Respiration • Shannon Diversity Index: H = -Σ(pi × ln pi) • Simpson's Index: D = Σ(ni/N)² • Population Growth: dN/dt = rN(K-N)/K • Energy Transfer: 10% rule between trophic levels Critical Values to Remember • CO₂ in atmosphere: ~420 ppm (increasing) • Global warming limit: 1.5°C above pre-industrial • Ozone layer: 15-35 km altitude (stratosphere) • Species extinction rate: 100-1000× natural rate • Safe drinking water pH: 6.5-8.5 Environmental Science Complete Notes | B.Tech CSE Exam Preparation B.Tech CSE | Exam Preparation Guide Maulana Abul Kalam Azad University of Technology Made with Genspark
- 2. Study all units thoroughly and practice previous year questions for better understanding