Environment, Ecology & Biodiversity – Concise Revision Notes
(Tailored for JKSSB Accounts Assistant (Finance) – General Knowledge)
1. Environment – Basic Concepts
- Definition: The sum total of all external conditions (biotic & abiotic) that influence the life, development, and survival of an organism.
- Components
- Biotic – Living organisms (plants, animals, microbes). – Abiotic – Non‑living factors (temperature, light, water, soil, atmosphere, nutrients).
- Key Highlights
- Environment = Habitat + Niche (role of an organism).
- Homeostasis – Self‑regulating processes that keep internal conditions stable despite external changes.
2. Ecology – Study of Interactions – Definition: Scientific study of the relationships between living organisms and their environment.
- Hierarchy of Ecological Organization
- Organism → 2. Population → 3. Community → 4. Ecosystem → 5. Biome → 6. Biosphere.
- Core Principles
- Energy Flow – Unidirectional (sun → producers → consumers → decomposers).
- Material Cycling – Nutrients move in biogeochemical cycles (C, N, P, S, water).
- Population Dynamics – Birth, death, immigration, emigration; governed by carrying capacity (K).
- Succession – Progressive change in species composition; primary (on bare rock) vs secondary (after disturbance). – Mnemonics
- Trophic Levels: “Please Eat Meat, but Don’t Forget Veggies” → Producers, Erst (Primary) consumers, Meat (Secondary) consumers, Don’t (Tertiary) consumers, Forget (Decomposers) Veggies.
- Biogeochemical Cycles: “Cats NAP in Water” → Carbon, Nitrogen, Aphosphorus (actually P), Water.
3. Ecosystem – Structure & Function
| Aspect | Description |
|---|---|
| Structure | Abiotic (climate, soil, water) + Biotic (producers, consumers, decomposers). |
| Function | Energy flow, nutrient cycling, ecological stability, productivity. |
| Productivity | Gross Primary Productivity (GPP) – total solar energy captured. Net Primary Productivity (NPP) – GPP minus plant respiration (available to herbivores). |
| Ecological Pyramids | Pyramid of Numbers (often inverted), Biomass (usually upright), Energy (always upright, 10 % rule). |
Types of Ecosystems
| Category | Examples (India) | Salient Features |
|---|---|---|
| Terrestrial | Tropical rainforest (Western Ghats), Deciduous forest (Central India), Thorn forest (Rajasthan), Grassland (Tarai), Desert (Thar), Alpine tundra (Himalayas) | Defined by precipitation & temperature; vegetation determines fauna. |
| Freshwater (Lentic) | Lakes (Dal, Wular), Ponds, Swamps | Standing water; stratification (epilimnion, metalimnion, hypolimnion). |
| Freshwater (Lotic) | Rivers (Ganga, Brahmaputra), Streams | Flowing water; high oxygen, continuous renewal of nutrients. |
| Marine | Coral reefs (Andaman & Nicobar), Estuaries (Sundarbans), Open ocean, Deep sea | Salinity ~35 %; high biodiversity in coral reefs; estuaries act as nurseries. |
| Artificial | Reservoirs, Aquaculture ponds, Urban parks | Man‑modified; often require management for sustainability. |
4. Biodiversity – Variety of Life
- Definition: Variability among living organisms from all sources, including terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part. #### Levels of Biodiversity
| Level | What it Means | Examples |
|---|---|---|
| Genetic | Variety of genes within a species. | Different rice varieties (Basmati, IR64). |
| Species | Variety of species within a region. | Bengal tiger, Indian one‑horned rhinoceros. |
| Ecosystem | Variety of habitats, communities, ecological processes. | Mangroves, coral reefs, grasslands. |
- Mnemonic: “GSE” → Genetic, Species, Ecosystem.
Importance of Biodiversity
- Ecological – Stabilizes ecosystems, provides resilience against disturbances.
- Economic – Source of food, medicine, fibers, tourism (ecotourism).
- Cultural – Spiritual, aesthetic, traditional knowledge.
- Scientific – Basis for research, biotechnology, climate regulation.
5. Biodiversity Hotspots
- Criteria (Myers et al., 2000):
- ≥ 1,500 endemic vascular plant species (>0.5 % of world’s total). 2. ≥ 70 % loss of original habitat.
- World Hotspots (36) – Notable ones:
- Mediterranean Basin, California Floristic Province, Madagascar & Indian Ocean Islands, Sundaland, Western Ghats & Sri Lanka, Himalaya, Indo‑Burma. – India’s Hotspots (4 recognised):
- Western Ghats & Sri Lanka – Endemic amphibians, Shola grasslands.
- Eastern Himalayas – High species richness of orchids, rhododendrons.
- Indo‑Burma (North‑East) – Mammals like Hoolock gibbon, rare birds.
- Sundaland (Nicobar Islands) – Coral reefs, mangroves.
- Key Highlight: Protecting hotspots yields disproportionate conservation benefits because they harbour a large fraction of endemic species under severe threat.
6. Threats to Biodiversity
| Threat | Mechanism | Examples in India |
|---|---|---|
| Habitat Loss & Fragmentation | Conversion to agriculture, urbanization, mining. | Deforestation in Northeast, conversion of wetlands to paddy fields. |
| Overexploitation | Unsustainable hunting, fishing, logging. | Poaching of tigers, overfishing of marine stocks. |
| Invasive Alien Species | Outcompete natives, alter habitats. | Lantana camara (plant), African catfish Clarias gariepinus. |
| Pollution | Chemical load degrades water/soil/air. | Industrial effluents in Yamuna, plastic debris in Ganges. |
| Climate Change | Shifts in temperature/precipitation, phenology mismatch. | Glacier retreat affecting Himalayan flora, coral bleaching in Andaman. |
| Disease | Pathogens spill over from livestock/humans. | Chytrid fungus affecting amphibians in Western Ghats. |
7. Conservation Strategies
7.1 In‑Situ Conservation (Protected Areas)
| Category | Legal Status (India) | Examples |
|---|---|---|
| National Park | Strict protection; no human habitation. | Jim Corbett (Uttarakhand), Kaziranga (Assam). |
| Wildlife Sanctuary | Limited human activities allowed. | Periyar (Kerala), Ranthambhore (Rajasthan). |
| Biosphere Reserve | Core zone (strict), buffer (limited use), transition (sustainable). | Nilgiri, Sundarbans, Nanda Devi. |
| Community Reserve | Managed by local communities for wildlife. | Khonoma (Nagaland), Tawang (Arunachal Pradesh). |
| Conservation Reserve | Buffer zones around PAs, managed for wildlife. | Kodaikanal (Tamil Nadu). |
- Mnemonic: “PANCS” → Parks, Allied Sanctuaries, National Parks, Community Reserves, Sanctuaries (or Biosphere).
7.2 Ex‑Situ Conservation
| Method | Purpose | Examples |
|---|---|---|
| Zoos & Aquariums | Captive breeding, education. | Delhi Zoo, Chennai Snake Park. |
| Botanical Gardens | Germplasm preservation, research. | Indian Botanic Garden (Kolkata), NBRI (Lucknow). |
| Seed Banks | Long‑term storage of plant genetic resources. | National Bureau of Plant Genetic Resources (NBPGR), New Delhi. |
| Cryopreservation | Storage of gametes/embryos at ultra‑low temps. | Buffalo semen bank, fish sperm banks. |
| Gene Banks | DNA libraries for future breeding. | International Rice Research Institute (IRRI) germplasm. |
7.3 Policy & Legislative Framework (India)
| Act / Policy | Year | Core Provision |
|---|---|---|
| Wildlife Protection Act | 1972 | Protects wild animals, birds, plants; establishes PAs. |
| Forest (Conservation) Act | 1980 | Requires central approval for non‑forest use of forest land. |
| Environment Protection Act | 1986 | Umbrella act; empowers central govt to take measures to protect environment. |
| Biological Diversity Act | 2002 | Implements CBD; sets up National Biodiversity Authority (NBA), State Biodiversity Boards (SBBs), Biodiversity Management Committees (BMCs). |
| National Wildlife Action Plan (NWAP) | 2017‑2031 | Landscape‑based conservation, climate‑change integration, community participation. |
| National Biodiversity Action Plan (NBAP) | 2008 (updated 2014) | 12 national targets aligned with Aichi Biodiversity Targets. |
| Green India Mission | 2010 (under NAPCC) | Increase forest/tree cover, improve ecosystem services, livelihoods. |
| National Clean Air Programme (NCAP) | 2019 | Reduce particulate matter (PM2.5/PM10) in 102 cities by 20‑30 % by 2024. |
| Swachh Bharat Mission (Gramin & Urban) | 2014 | Solid waste management, open‑defecation free India. |
7.4 International Agreements (Relevant for GK)
| Agreement | Year | Main Objective |
|---|---|---|
| Convention on Biological Diversity (CBD) | 1992 | Conservation, sustainable use, fair benefit‑sharing of genetic resources. |
| Cartagena Protocol on Biosafety | 2000 | Safe handling, transport, use of living modified organisms (LMOs). |
| Nagoya Protocol | 2010 | Access to genetic resources & benefit‑sharing. |
| Ramsar Convention on Wetlands | 1971 | Conservation & wise use of wetlands. |
| CITES (Convention on International Trade in Endangered Species) | 1973 | Regulate international trade of specimens of wild animals & plants. |
| UN Convention to Combat Desertification (UNCCD) | 1994 | Combat desertification & mitigate drought effects. |
| UN Framework Convention on Climate Change (UNFCCC) | 1992 | Stabilize greenhouse gas concentrations. |
| Kyoto Protocol | 1997 | Binding emission reduction targets for developed countries. |
| Paris Agreement | 2015 | Limit global warming to well below 2 °C, pursue 1.5 °C. |
| World Heritage Convention | 1972 | Protect cultural & natural heritage of outstanding universal value. |
| Bonn Convention (Migratory Species) | 1979 | Conservation of migratory species across their range. |
8. Environmental Pollution – Types & Control
| Pollution Type | Primary Sources | Major Effects | Key Control Measures (India) |
|---|---|---|---|
| Air Pollution | Vehicular exhaust, industrial emissions, biomass burning, construction dust. | Respiratory diseases, acid rain, smog, climate forcing. | National Air Quality Index (NAQI), BS‑VI vehicular norms, Odd‑Even scheme, promotion of electric vehicles, National Clean Air Programme. |
| Water Pollution | Domestic sewage, industrial effluents, agricultural runoff (fertilizers, pesticides), oil spills. | Eutrophication, loss of aquatic life, spread of water‑borne diseases. | Water (Prevention & Control of Pollution) Act, 1974; Namami Gange programme; effluent treatment plants (ETPs); zero liquid discharge (ZLD) mandates. |
| Soil Pollution | Heavy metals (lead, cadmium), pesticides, plastic waste, mining tailings. | Reduced fertility, bioaccumulation in food chain, groundwater contamination. | Soil Health Card scheme; promotion of organic farming; regulation of pesticide use (Insecticides Act, 1968). |
| Noise Pollution | Traffic, industries, loudspeakers, construction. | Hearing loss, stress, cardiovascular effects. | Noise Pollution (Regulation & Control) Rules, 2000; silent zones near hospitals/schools. |
| Plastic Pollution | Single‑use plastics, packaging, fishing gear. | Marine ingestion, microplastics in food, soil degradation. | Plastic Waste Management Rules, 2016 (amended 2021); ban on identified single‑use items; Extended Producer Responsibility (EPR). |
| E‑Waste | Discarded computers, mobile phones, batteries. | Toxic leachate (lead, mercury), health hazards for informal recyclers. | E‑Waste (Management) Rules, 2016; authorized collection centres; producer responsibility. |
- Mnemonics for Pollution Control: “3R + E” → Reduce, Reuse, Recycle + Extended Producer Responsibility.
9. Climate Change – Basics for GK
- Greenhouse Gases (GHGs): CO₂, CH₄, N₂O, fluorinated gases (HFCs, PFCs, SF₆, NF₃).
- Global Warming Potential (GWP) – Relative warming effect over 100 years (CO₂ = 1).
| Gas | Approx. GWP (100‑yr) | Major Sources |
|---|---|---|
| CO₂ | 1 | Fossil fuel combustion, deforestation, cement production. |
| CH₄ | 28‑34 | Enteric fermentation (livestock), rice paddies, landfills, natural gas leakage. |
| N₂O | 265‑298 | Fertilizer use, industrial processes, burning biomass. |
| HFC‑134a | 1,300 | Refrigeration, air‑conditioning. |
| SF₆ | 23,500 | Electrical insulation, magnesium industry. |
- Impacts (India‑specific):
- Temperature rise → increased heat stress, altered cropping patterns.
- Monsoon variability → floods/droughts.
- Glacial retreat → reduced river flow in Indus, Ganga, Brahmaputra basins.
- Sea‑level rise → coastal inundation, salinity intrusion (Sundarbans).
- Ocean acidification → coral bleaching (Andaman & Nicobar).
- Mitigation Strategies (National Action Plan on Climate Change – NAPCC):
- National Solar Mission – 100 GW solar by 2022 (now revised upward). 2. National Mission for Enhanced Energy Efficiency – Perform, Achieve, Trade (PAT) scheme.
- National Mission on Sustainable Habitat – Green buildings, public transport.
- National Water Mission – 20 % water use efficiency.
- National Mission for Sustaining the Himalayan Ecosystem.
- National Mission for a Green India – Afforestation, eco‑restoration.
- National Mission for Sustainable Agriculture.
- National Mission on Strategic Knowledge for Climate Change.
- Adaptation: Climate‑resilient crops, flood‑plain zoning, early warning systems, mangrove restoration.
- Key Highlight: India’s Intended Nationally Determined Contribution (INDC) pledges to reduce emissions intensity of GDP by 33‑35 % by 2030 (from 2005 levels) and achieve 40 % cumulative electric power capacity from non‑fossil sources.
10. Sustainable Development & Environment
- Sustainable Development Goals (SDGs) linked to environment:
- SDG 6 – Clean Water & Sanitation.
- SDG 7 – Affordable & Clean Energy.
- SDG 11 – Sustainable Cities & Communities.
- SDG 12 – Responsible Consumption & Production.
- SDG 13 – Climate Action.
- SDG 14 – Life Below Water.
- SDG 15 – Life on Land.
- Concept of Ecological Footprint – Measure of human demand on Earth’s ecosystems; India’s per‑capita footprint is lower than global average but rising due to urbanization.
- Green GDP – Adjusted GDP that subtracts environmental degradation costs; used for measuring true welfare.
- Circular Economy – Keep resources in use for as long as possible, extract maximum value, then recover/regenerate products. Promoted via initiatives like Swachh Bharat, Plastic Waste Management, E‑Waste Rules.
11. Quick‑Reference Tables
11.1 Major Environmental Acts in India (Year & Core Focus)
| Act | Year | Core Focus |
|---|---|---|
| Wildlife Protection Act | 1972 | Protection of wild animals, birds, plants; establishment of PAs. |
| Water (Prevention & Control of Pollution) Act | 1974 | Prevention & control of water pollution; central & state boards. |
| Air (Prevention & Control of Pollution) Act | 1981 | Prevention & control of air pollution; CPCB & SPCBs. |
| Forest (Conservation) Act | 1980 | Regulation of diversion of forest land for non‑forest purposes. |
| Environment Protection Act | 1986 | Umbrella act; powers to take measures to protect & improve environment. |
| Biological Diversity Act | 2002 | Conservation of biodiversity, sustainable use, fair benefit‑sharing. |
| National Green Tribunal Act | 2010 | Speedy disposal of environmental cases. |
| Hazardous and Other Wastes (Management & Transboundary Movement) Rules | 2016 | Management of hazardous waste, e‑waste, biomedical waste. |
| Plastic Waste Management Rules | 2016 (amended 2021) | Regulation of plastic waste, EPR, phase‑out of identified items. |
| Solid Waste Management Rules | 2016 | Segregation, processing, disposal of municipal solid waste. |
11.2 India’s Protected Area Network (Approx. Figures, 2023)
| Category | Number | Total Area (km²) |
|---|---|---|
| National Parks | 106 | 44,378 |
| Wildlife Sanctuaries | 564 | 122,560 |
| Biosphere Reserves | 18 | 68,330 |
| Conservation Reserves | 89 | 4,300 |
| Community Reserves | 215 | 2,100 |
| Total | ≈ 988 | ≈ 241,668 km² (~7.35 % of geographical area) |
11.3 India’s Biodiversity Hotspots – Key Species (Examples)
| Hotspot | Endemic Flora | Endemic Fauna |
|---|---|---|
| Western Ghats & Sri Lanka | Nilgiri orchids, Shola grasslands, Cinnamomum spp. | Lion‑tailed macaque, Nilgiri tahr, Purple frog. |
| Eastern Himalayas | Rhododendron spp., Orchids (e.g., Paphiopedilum) | Red panda, Snow leopard, Himalayan black bear. |
| Indo‑Burma (NE) | Dipterocarp spp., Bamboo diversity | Hoolock gibbon, Clouded leopard, White‑winged duck. |
| Sundaland (Nicobar) | Mangrove species (Rhizophora, Avicennia) | Nicobar megapode, Saltwater crocodile, Leopard cat. |
12. Study Tips & Revision Hacks 1. Flashcards – One side: term (e.g., “GWP”), other side: definition & example.
- Mind Maps – Connect “Biodiversity” → levels → threats → conservation → laws. 3. Mnemonics Recap – Trophic levels: Please Eat Meat, but Don’t Forget Veggies
- Biodiversity levels: GSE (Genetic, Species, Ecosystem)
- Protected Areas: PANCS (Parks, Sanctuaries, National Parks, Community, Sanctuaries/Biosphere)
- Pollution control: 3R + E (Reduce, Reuse, Recycle + Extended Producer Responsibility)
- Practice with Previous Year Questions – Focus on:
- Matching acts with years.
- Identifying hotspots and their flagship species.
- Numerical: e.g., “If GPP = 1000 units, plant respiration = 300 units, what is NPP?” (Answer: 700).
- Diagrams – Draw a simple energy flow diagram (Sun → Producer → Primary Consumer → Secondary Consumer → Tertiary Consumer → Decomposer) and label the 10 % rule.
- Timed Quizzes – 5‑minute recall of:
- List of 5 greenhouse gases with GWP.
- Names of India’s 4 biodiversity hotspots.
- Three major international conventions (CBD, Ramsar, CITES).
13. Final Quick‑Recap (Bullet Form)
- Environment = biotic + abiotic; habitat vs niche.
- Ecology = study of interactions; hierarchy organism → biosphere.
- Energy flow = unidirectional, 10 % rule; nutrient cycles = C, N, P, water.
- Ecosystems = terrestrial, freshwater (lentic/lotic), marine, artificial.
- Biodiversity = genetic, species, ecosystem; vital for ecology, economy, culture.
- Hotspots = high endemism + high loss; India has 4 (Western Ghats, Eastern Himalayas, Indo‑Burma, Sundaland).
- Threats = habitat loss, overexploitation, invasives, pollution, climate change, disease.
- Conservation = in‑situ (PAs: NP, WS, BR, CR, Cons.Res) + ex‑situ (zoos, gardens, seed banks, cryopreservation).
- Key Laws – Wildlife Protection Act (1972), Forest Conservation Act (1980), EPA (1986), Biodiversity Act (2002).
- International Agreements – CBD, Ramsar, CITES, UNFCCC/Kyoto/Paris, Bonn, UNCCD.
- Pollution = air, water, soil, noise, plastic, e‑waste; controlled via specific rules & missions. – Climate Change = GHGs (CO₂, CH₄, N₂O, fluorinated); impacts on monsoon, glaciers, sea‑level; mitigation via NAPCC (solar, EE, habitat, water, Himalaya, Green India, agriculture, knowledge).
- SDGs linked to environment (6,7,11,12,13,14,15).
- Remember: 3R + E for waste; GSE for biodiversity; PANCS for protected areas; Please Eat Meat… for trophic levels.
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End of Notes – Good luck with your revision!
