UPSC Prelims Environment and Ecology Syllabus 2025

Q: What is the syllabus of Ecology and Environment in UPSC?

The UPSC syllabus includes general issues on environmental ecology, biodiversity, and climate change without requiring subject-specific specialization.

Q: How to study Environment and Ecology for UPSC Prelims?

Focus on NCERTs, standard reference books, current affairs, and previous year questions to build conceptual clarity and stay updated.

Q: What is the weightage of Environment and Ecology in UPSC Prelims?

Environment-related questions usually account for 15–20% of the General Studies Paper I.

Q: Which is the hardest subject in UPSC Prelims?

Many aspirants find Indian Polity and Economy challenging due to conceptual depth and dynamic current affairs overlap.

Q: Which subject has the shortest syllabus in UPSC?

Science and Technology is often considered to have the shortest static syllabus, though current affairs make it unpredictable.

Table of Contents☰

UPSC Prelims Environment and Ecology syllabus includes important concepts like environment, biodiversity and ecological systems. Topics like ecosystems, climate change and its conservation and national and international environmental laws. To qualify UPSC Civil Services Examination, one should be well aware about these concepts.

UPSC Prelims Environment and Ecology Syllabus 2025

While the UPSC Prelims syllabus does not provide detailed subtopics under Environment and Ecology, a general outline can be derived based on previous years’ questions and themes. The following areas are considered important:

Ecology:Basic concepts related to ecosystems, their structure and function, biotic and abiotic components, food chains, food webs, and ecological interactions.
Biodiversity: Types and levels of biodiversity, biodiversity hotspots, endangered and endemic species, conservation efforts, and key international conventions (e.g., CBD, CITES).
Climate Change:Causes and consequences of climate change, mitigation and adaptation strategies, and global initiatives like the Paris Agreement and IPCC reports.
Environmental Pollution: Types of pollution—air, water, soil, and noise—their sources, impacts, and control measures including national programmes and pollution control boards.
Environmental Degradation:Issues such as deforestation, land degradation, desertification, and soil erosion, along with their ecological and socio-economic impacts.
Conservation Efforts:Protected areas including biosphere reserves, national parks, wildlife sanctuaries, and community reserves; in-situ and ex-situ conservation methods.
Environmental Laws and Policies:Overview of major environmental legislations (e.g., Environment Protection Act, Forest Conservation Act), national policies, and regulatory institutions.
Sustainable Development:Principles of sustainable development, Sustainable Development Goals (SDGs), and the role of stakeholders in promoting environmental sustainability.
Environmental Movements:Important environmental movements and campaigns in India and globally, including their objectives, leadership, and outcomes.
Current Affairs:Recent developments, national and international reports, government initiatives, and emerging issues related to environment and ecology.

UPSC Prelims Environment and Ecology Topic Wise Syllabus 2025

The table below contains the detailed UPSC Environment and Ecology Syllabus to prepare for 2025:

Part I: Environment and Ecology
1. Basics of Environment and Ecology	Categories of Environment Features of Environment Components of Environment Ecology Basics Types of Environment
2. Ecosystem	Definition of an Ecosystem, Dynamics Within Ecosystems, Elements Comprising Ecosystems, Interconnections Within Food Chains and Webs, Population Pyramids, and Influences of Living and Non-Living Factors. Variations in Ecosystem Types, Strategies for Preserving Ecosystems, Alterations Observed in Ecosystems, Examples Like Eutrophication, Coral Reefs, Initiatives Such as The Namami Ganga Program, and Recent Actions Taken.
3. Biogeochemical Cycles	Gaseous Cycle, Sedimentary Cycle, Human Impact on the Carbon Cycle, and Nutrient Cycle
4. Pollution and Degradation	Degradation of Land, Methods For Preserving Soil Integrity, Erosion of Soil, Practices For Managing Land Sustainably, Expansion of Deserts, Contamination of The Air, Disturbances Caused by Noise, Presence of Plastic Waste, Radiation Contamination, Increase in Temperature of Water Bodies Due to Human Activities, Deterioration of Water Quality And Pollution of Oceans, Negative Impacts of Mining on The Environment, Strategies Like Bioremediation for Restoring Ecological Balance, Connections Between Environmental Pollution and Human Health, Phenomenon of Acid Precipitation.
5. Environmental Issues	Indian Himalayan Sand Mining Palm Oil Wildlife Deaths Human Animal Conflict Genetically Engineered Trees Cost of Environmental Degradation
6. Environment Impact Assessment	Environmental Impact Assessment: Need for EIA, EIA Cycle and procedure
7. Population Ecology	Characteristics of Populations, Models Explaining Population Growth, Various Species and The Dangers They Face, and The Maximum Population Earth can Support.
8. Waste Management	Biomedical Waste E-Waste Management Hazardous Waste Solid Waste Management
Part II: Biodiversity
1. Basics of Biodiversity	Types of Biodiversity, Scales At Which Biodiversity Is Assessed, Methods For Quantifying Biodiversity, Different Types of Services Provided by Biodiversity Approaches to Safeguarding Biodiversity, Red Data Book, Factors Posing Risks to Biodiversity Disappearance of Species, Categories and Reasons Behind Species Disappearance, Repercussions Of Species Loss, Endangered Species Native to India Efforts To Conserve Biodiversity Within India, International Agreements And Guidelines Aimed At Safeguarding Biodiversity.
2. Indian Biodiversity	Indian Bio-Geographical Classification, Fauna and Flora Diversity Animal Diversity of India: Mammals Critically Endangered Animals, Mammals, Birds, Fishes, Corals, Man- Animal Conflict. Plant Diversity of India: Plant Classification Insectivorous Plants Invasive Alien Flora Medicinal Plants Tree Characteristics Schedule Animals of WPA, 1972 Marine Organism: Plankton and Its Types, Seagrass and Seaweed
3. Biodiversity Conservation Initiatives	National Initiatives: Wildlife Sanctuary and National Parks Conservation Reserves and Community Reserves, Coastal Protected Areas, Sacred Groves of India, Export Prohibited Items. Global Initiatives: Man And Biosphere, Biosphere Reserves, National Biosphere Reserve Programme, World Network of Biosphere Reserves, Biodiversity Hotspots, World Heritage Sites
4. Conservation Efforts	Project Tiger, Lion, Leopards, Elephant, Secure Himalaya, Hangul Crocodile Conservation Project Captive Breeding, and Other Government Measures
Part III: Climate Change
1. Basic Understandings	Greenhouse Gases and Greenhouse Effects; Global warming and its potential Ozone depletion; Ocean Acidification and Rising Sea Level India and Climate Change: Agriculture and Food Security, Water Stress, Sea Level, Rise, Ecosystem and Biodiversity, Health
2. India and Climate Change	Carbon Mitigation Strategies: Carbon Sequestration Carbon Credit and Offsetting, Carbon Tax, and Geo-Engineering. Climate Change in India Indian Network on Climate Change Assessment, NATCOM, India’s Policy Structure Relevant to GHG Mitigation, Green Building, Griha, NAFCC
3. Climate Change Organizations	IPCC and IPCC Reports; UNFCCC and Important Conference of Parties. Kyoto Protocol and Other Developments REDD and REDD+ , Global Environment Facilities, Climate Smart Agriculture, and the National Green House Gas Inventories Programme. Green Economy, Climate Finance, and Other Global Initiatives
Part IV: Agriculture
Agriculture	Crop and its Classification, Various Tillage Operations, Cropping Systems and Patterns, Types of Farming System, Sustainable Agriculture, and its Components Organic Farming and Natural Farming, Integrated Farming System, Soil and its characteristics.
Part V: Miscellaneous
1. Acts and Policies	Wildlife Protection Act (WPA) 1972 Environment Protection Act (EPA) 1986 National Forest Policy, 1988 Biological Diversity Act, 2002 FRA 2006 CRZ Wetland Rules 2010 National Green Tribunal, The Ozone Depleting Substances Rules. Bio-Medical Waste Management Rules, 2016, E-Waste Management Rules, 2016, Plastic Waste Management (PWM) Rules, 2016, Wetland Rules 2010 National Green Tribunal,
2. Environmental Organisations	Organisations, their Origin, and various initiatives taken Animal Welfare Board, Central Zoo Authority, National Biodiversity Authority, Wildlife Crime Control Bureau
3. Environmental Conventions:	UNCED, UNCCD, UNCBD, Ramsar Convention, CITES, TRAFFIC, CMS, IUCN, Stockholm, Basel, and Rotterdam Convention, Vienna Convention and Montreal Protocol, Kigali Agreement, Globally Important Agricultural Heritage Systems, and Minamata Convention
4. Other Facts	State Animals and State Birds, Animal and Plant species in News, National Parks, Wildlife Sanctuary, Tiger Reserves, Elephant reserves, Lakes, Dams, India’s Biosphere Reserves, List of Sacred Groves, Mangrove sites, etc.

Environment Questions in UPSC Prelims

The environment and ecology questions constitute a major portion in UPSC Prelims . Here is an analysis of Environment and Ecology Questions over the years:

Environment and Ecology questions in the UPSC Prelims have been a significant part of the exam in recent years. Here are the number of Environment and Ecology questions in the past few years:

UPSC Prelims Year	Number of Questions
2024	15
2023	10
2022	12
2021	20
2020	22
2019	21
2018	17
2017	15

UPSC Prelims Environment and Ecology Syllabus 2025 Important Books

To effectively prepare for the Environment and Ecology section of the UPSC Prelims 2025, it is crucial to refer to reliable and comprehensible resources. The right study material will help you build a strong conceptual understanding of key topics such as ecosystems, biodiversity, climate change, environmental laws, and sustainable development.

Below is a list of recommended books that comprehensively cover the syllabus and are well-suited for aspirants aiming for conceptual clarity and exam-oriented preparation.

Science NCERT: Class 6 to 10 (Environment Related Topics)
Biology NCERT: Class 12 (Environment Related Topics)
Geography NCERT: Class 6 to 11 (Environment Related Topics)
Environment and Ecology – By Vaishali Anand

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