⭐ Sabse Important Points · एक नज़र में
- Himalayas: Young fold mountains, source of perennial rivers, act as climatic barrier.
- Northern Plains: Formed by alluvium, includes Bhangar (old alluvium) and Khadar (new alluvium); prone to floods.
- Northern Plains: Formed by alluvial deposits of Indus, Ganga, and Brahmaputra; highly fertile and densely populated.
- Southern Plains: Includes Magadh plain and plateau fringe; relatively drier and affected by drought.
- Peninsular Plateau: Oldest landmass, rich in minerals, includes Deccan Trap and Chota Nagpur Plateau.
- Plateau Region: Extends over parts of Kaimur, Rohtas, and Gaya; rich in minerals like limestone and mica.
Introduction · परिचय
The geography of India and Bihar is a core component of the BPSC General Studies syllabus. It covers physical features, climate, drainage, soils, vegetation, and human geography. For Bihar, focus on its physiographic divisions, rivers, and agro-climatic zones. These notes provide a concise revision of key concepts, comparisons, and exam-oriented tips.
Physiographic Divisions of India
India is divided into six major physiographic regions: the Himalayas, the Northern Plains, the Peninsular Plateau, the Indian Desert, the Coastal Plains, and the Islands. Each region has distinct geological history, relief, and economic significance.
| Himalayas | Peninsular Plateau |
|---|---|
| Young fold mountains | Old stable landmass |
| Perennial rivers | Seasonal rivers |
| High seismic activity | Low seismic activity |
| Forests and tourism | Minerals and mining |
⭐ Key Points · याद रखने वाली बातें
- Himalayas: Young fold mountains, source of perennial rivers, act as climatic barrier.
- Northern Plains: Formed by alluvial deposits of Indus, Ganga, and Brahmaputra; highly fertile and densely populated.
- Peninsular Plateau: Oldest landmass, rich in minerals, includes Deccan Trap and Chota Nagpur Plateau.
- Indian Desert: Thar Desert in Rajasthan, arid climate, sand dunes, and inland drainage.
- Coastal Plains: Eastern (Coromandel) and Western (Konkan, Kanara, Malabar) plains; Western is narrow and dissected.
- Islands: Andaman & Nicobar (Bay of Bengal) and Lakshadweep (Arabian Sea); coral and volcanic origins.
✍️ Solved Example 1 · हल किया हुआ उदाहरण
❓ Question: Which physiographic division of India is the oldest landmass and rich in minerals?
✅ Solution: Peninsular Plateau
💡 Explanation: The Peninsular Plateau is composed of ancient crystalline rocks and is a storehouse of minerals like iron, manganese, and coal.
Geography of Bihar: Physiography and Drainage
Bihar is divided into three physiographic units: the Northern Plains (Gangetic plain north of the Ganga), the Southern Plains (south of the Ganga), and the Plateau region (Chota Nagpur Plateau fringe in the south). The state is drained by the Ganga and its tributaries, with distinct flood and drought zones.
- Ganga enters Bihar from west
- Flows eastward
- Joins tributaries from north and south
- Forms fertile plains
- Exits into West Bengal
⭐ Key Points · याद रखने वाली बातें
- Northern Plains: Formed by alluvium, includes Bhangar (old alluvium) and Khadar (new alluvium); prone to floods.
- Southern Plains: Includes Magadh plain and plateau fringe; relatively drier and affected by drought.
- Plateau Region: Extends over parts of Kaimur, Rohtas, and Gaya; rich in minerals like limestone and mica.
- Ganga River: Main axis, flows from west to east; major tributaries: Ghaghara, Gandak, Kosi (north) and Son, Punpun (south).
- Kosi River: Known as 'Sorrow of Bihar' due to frequent course changes and floods.
- Agro-climatic Zones: Bihar has three zones: Zone I (North-West), Zone II (North-East), Zone III (South).
✍️ Solved Example 1 · हल किया हुआ उदाहरण
❓ Question: Which river is known as the 'Sorrow of Bihar' and why?
✅ Solution: Kosi River
💡 Explanation: The Kosi River shifts its course frequently and causes severe floods in northern Bihar, hence called the Sorrow of Bihar.
Practice Questions · खुद हल करके देखो
पहले खुद try karo, phir “Answer dekho” dabakar check karo. 👇
Q1Which of the following is the youngest physiographic division of India?
👀 Answer dekho
✅ Answer: Himalayas
💡 Explanation: The Himalayas are young fold mountains formed by the collision of Indian and Eurasian plates.
Q2The Chota Nagpur Plateau mainly lies in which state?
👀 Answer dekho
✅ Answer: Jharkhand
💡 Explanation: The Chota Nagpur Plateau covers most of Jharkhand and parts of Bihar, West Bengal, and Odisha.
Q3Which agro-climatic zone of Bihar is most prone to drought?
👀 Answer dekho
✅ Answer: Zone III (South Bihar)
💡 Explanation: Zone III, covering southern Bihar, receives less rainfall and is drought-prone compared to the northern zones.
⚠️ Common Mistakes · ये गलतियाँ बिल्कुल मत करना
- Confusing Bhangar (old alluvium) with Khadar (new alluvium): Remember Khadar is renewed by floods and more fertile.
- Mixing up the Kosi and Gandak rivers: Kosi is the 'Sorrow of Bihar', while Gandak is a major tributary from Nepal.
- Assuming all of Bihar is flood-prone: The southern plateau region is drought-prone, not flood-prone.
⚡ Quick Revision · Exam से पहले 2 मिनट में दोहराओ
- Physiographic divisions of India: Himalayas, Northern Plains, Peninsular Plateau, Desert, Coastal Plains, Islands.
- Bihar's three physiographic units: Northern Plains, Southern Plains, Plateau region.
- Kosi River: 'Sorrow of Bihar' due to frequent floods and course changes.
- Bihar agro-climatic zones: Zone I (North-West), Zone II (North-East), Zone III (South).
- Peninsular Plateau: Oldest landmass, mineral-rich, includes Deccan Trap and Chota Nagpur Plateau.