PEOPLE, DEVELOPMENT
& ENVIRONMENT (PDE)

MODULE 01: DEVELOPMENT & ENVIRONMENT — MDGs & SDGs

Figure 1.1: The 2030 Agenda is a universal call to end poverty, protect the planet and ensure peace & prosperity for all people.

1.1 Millennium Development Goals (MDGs) — 2000 to 2015

The MDGs were adopted at the UN Millennium Summit in September 2000, with all 189 UN member states agreeing to achieve 8 goals by 2015. They arose from the Millennium Declaration.

1.2 Sustainable Development Goals (SDGs) — The 2030 Agenda

The SDGs were adopted on 25 September 2015 at the UN Sustainable Development Summit in New York. They emerged from the Rio+20 Conference (2012) and replaced the MDGs. India's NITI Aayog coordinates SDG implementation.

MODULE 02: ECOLOGY, ECOSYSTEM & BIODIVERSITY

Fig 2.1: Forest ecosystems host 80% of world's terrestrial biodiversity.

Fig 2.2: Coral reefs — called "Rainforests of the Sea" — support 25% of all marine species.

2.1 Ecology — Basic Concepts

Ecology (coined by Ernst Haeckel, 1866) is the scientific study of interactions between organisms and their environment. The term "Environment" comes from the French word Environner (to surround).

2.2 Components of an Ecosystem

2.3 Food Chain, Food Web & Ecological Pyramids

2.4 Biodiversity — Levels & Threats

Biodiversity (term coined by Walter G. Rosen, 1985) refers to the variety of life on Earth at all its levels — from genes to ecosystems. The Convention on Biological Diversity (CBD) was adopted at the Rio Earth Summit, 1992.

2.5 Conservation Methods

Fig 2.3: Project Tiger (1973) — India's flagship in-situ conservation. Tiger population rose from 1,827 (2014) to 3,167 (2022).

Fig 2.4: Deforestation threat — these ancient forests are being cleared at an alarming rate. India loses ~1.5 million hectares of forest annually. Deforestation is the #1 threat to biodiversity — when habitats are lost, species are lost forever.

MODULE 03: ENVIRONMENTAL POLLUTION & WASTE MANAGEMENT

Fig 3.1: Air pollution — particulate matter (PM2.5 & PM10) causes 7 million deaths annually (WHO).

Fig 3.2: Water pollution — 2 billion people lack access to safe drinking water globally.

3.1 Air Pollution

Air pollution is the presence of harmful substances (pollutants) in the atmosphere beyond permissible limits. India follows National Ambient Air Quality Standards (NAAQS).

3.2 Water Pollution

Figure 3.3: Untreated industrial effluents and sewage entering rivers — India generates over 3.5 million tonnes of plastic waste annually. The Namami Gange Mission (2014) aims to clean the river Ganga. Industrial effluents discharged untreated into rivers are a major source of water pollution.

3.3 Noise Pollution — Permissible Levels (India)

3.4 Waste Management

Fig 3.4: Solid Waste Management — India generates ~62 million tonnes of solid waste annually.

Fig 3.5: E-waste — India is the 3rd largest e-waste generator in the world (after China & USA).

MODULE 04: CLIMATE CHANGE, GLOBAL WARMING & OZONE DEPLETION

Fig 4.1: Industrial emissions — power plants and factories release CO₂, SO₂ and NOₓ, the primary drivers of the enhanced greenhouse effect and global warming.

Fig 4.2: Earth's night lights from space — cities burning fossil fuels 24/7 release GHGs. The IPCC reports global temperatures have risen by ~1.1°C since pre-industrial times (1850–1900).

4.1 The Greenhouse Effect

The Greenhouse Effect is a natural process by which certain gases in Earth's atmosphere trap heat from the sun, keeping the planet warm. Without it, Earth's average temperature would be –18°C instead of the current +15°C.

4.2 Ozone Layer Depletion

The ozone layer (stratosphere, 15–35 km altitude) absorbs 97–99% of the sun's harmful ultraviolet (UV-B & UV-C) radiation. Chlorofluorocarbons (CFCs) and other ozone-depleting substances (ODS) destroy ozone molecules.

Figure 4.3: The "Ozone Hole" over Antarctica was discovered in 1985 by British scientists Farman, Gardiner & Shanklin. The Montreal Protocol (1987) successfully phased out CFCs.

4.3 Acid Rain

Acid rain has a pH below 5.6 (normal rainwater = 5.6). It is caused by SO₂ and NOₓ emissions from industries and vehicles reacting with atmospheric moisture.

4.4 Impacts of Climate Change — Socio-Economic & Political Dimensions

Fig 4.4: Industrial emissions — India is the 3rd largest CO₂ emitter globally. India's NDC pledges a 45% reduction in emissions intensity of GDP by 2030 (vs 2005 levels) and net-zero by 2070.

MODULE 05: NATURAL & ENERGY RESOURCES

Fig 5.1: Solar energy — India's installed solar capacity crossed 81 GW (2024). National Solar Mission targets 500 GW of renewable energy by 2030.

Fig 5.2: Wind energy — India is the 4th largest wind energy producer in the world. Gujarat, Tamil Nadu & Rajasthan are top states.

5.1 Renewable vs. Non-Renewable Energy

Figure 5.3: India's International Solar Alliance (ISA) — founded by India & France at COP21 (Paris, 2015). Headquartered at Gurugram. Aims to mobilise $1 trillion for solar energy in 121 sunshine countries by 2030.

MODULE 06: NATURAL HAZARDS, DISASTERS & MITIGATION

Fig 6.1: Floods — Most frequent natural disaster in India. States like Bihar, Assam & Uttar Pradesh are most flood-prone.

Fig 6.2: Earthquakes — India lies on the Eurasian and Indo-Australian plate boundary. ~59% of India's area is earthquake-prone (Zones II–V). Zone V (highest risk) covers NE India, J&K, Himachal, Uttarakhand, Gujarat & Andaman.

6.1 Key Definitions

6.2 Classification of Disasters

Figure 6.3: Disaster Risk Reduction — The Sendai Framework (2015–2030) is the global blueprint for DRR, adopted at the World Conference on Disaster Risk Reduction in Sendai, Japan.

6.3 Disaster Management in India — Institutional Framework

6.4 Sendai Framework for Disaster Risk Reduction (2015–2030)

MODULE 07: ENVIRONMENTAL PROTECTION — LAWS & INTERNATIONAL AGREEMENTS

Figure 7.1: International climate negotiations — the Conference of Parties (COP) meets annually under the UNFCCC. COP28 was held in Dubai (2023); COP29 in Baku, Azerbaijan (2024).

7.1 Indian Environmental Legislation — Chronological

7.2 International Environmental Agreements — Chronological

7.3 India's National Action Plan on Climate Change (NAPCC) — 2008

NAPCC was launched on 30 June 2008 by the Prime Minister's Council on Climate Change. It outlines India's strategy for climate change adaptation and mitigation with 8 National Missions.

MODULE 08: QUICK REVISION — ONE-LINERS & FLASH CARDS

Fig 8.1: "Earth provides enough to satisfy everyone's needs, but not everyone's greed." — Mahatma Gandhi

Fig 8.2: Only 2.5% of Earth's water is freshwater; only 0.3% of that is accessible surface water. Water conservation is critical.

8.1 High-Yield One-Liners (Exams Love These!)

8.2 Important Environment Days

8.3 PYQ — Expected Pattern Questions