This chapter tells us how people live with nature in hot tropical and subtropical regions. It starts with Renuka, who loves wildlife because of her uncle, a photographer. We learn about the Amazon Basin, full of rainforests and rivers, and the Ganga-Brahmaputra Basin with its plains and hills. It shows how people grow food, build homes, and use land differently in these areas. We also see how nature and humans depend on each other to survive.
1. Introduction
Renuka’s Story:
- Renuka gets excited when Shrikant Uncle comes home after four months.
- He’s a wildlife photographer who travels a lot.
- Renuka loves wildlife and forests because her uncle showed her nature books when she was small.
- People Around the World:
- People live in different places like dry deserts, cold frozen lands, and hot wet rainforests.
- They look different but need the same things—food, clothes, and a house.
- Kids everywhere play games, fight sometimes, make up, sing, dance, and help their families.
- They stay close to nature, learning to catch fish and collect things from forests early in life.
2. Life in the Amazon Basin
Location:
- The Amazon Basin is in the tropical region near the equator, between 10°N and 10°S.
- The Amazon River flows from mountains in the west to the Atlantic Ocean in the east.
- The river’s mouth is where it joins another water body.
- Amazon Basin:
- Many small rivers (tributaries) join the Amazon River to make the basin.
- It covers parts of Brazil, Peru, Bolivia, Ecuador, Colombia, and a bit of Venezuela.
- The equator passes through some of these countries.
2.1 Climate
Weather:
- Hot and wet all year because it’s on the equator.
- Days and nights are both hot and sticky with high humidity.
- Rain falls almost daily without warning.
- Daytime is very hot; night cools a little but stays humid.
2.2 Rainforests
Forests:
- Heavy rain makes thick forests grow.
- Ground stays dark and wet because tree leaves block sunlight.
- Only plants that like shade grow here, like orchids and bromeliads.
- Wildlife:
- Birds: Toucans, hummingbirds, and macaws have bright feathers and big beaks, making loud noises.
- Animals: Monkeys, sloths, and tapirs that eat ants live here.
- Reptiles: Crocodiles, snakes like pythons, anacondas, and boa constrictors are found.
- Insects: Thousands of types live in the basin.
- Fish: Many kinds, including piranha that eat flesh, swim in the river.
2.3 People of the Rainforests
Farming:
- People clear small forest patches to grow food.
- Men hunt and fish in rivers; women grow crops.
- Main crops: Tapioca, pineapple, sweet potato.
- Staple food: Manioc (cassava), which grows underground like potato.
- They also eat queen ants and egg sacs.
- Cash crops: Coffee, maize, and cocoa.
- Slash and Burn:
- Farmers cut and burn trees to make fields.
- Burning puts nutrients in soil for growing crops for a few years.
- When soil gets weak, they leave it and clear new land.
- Old land grows young trees, making soil good again later.
- Houses:
- Some live in thatched houses shaped like beehives.
- Others stay in big houses called Maloca with slanting roofs.
- Changes:
- Life is changing in the Amazon Basin.
- Before, only rivers took people into the forest’s heart.
- In 1970, a big highway opened up all areas.
- Planes and helicopters now reach different places.
- Old tribes were pushed out and settled in new areas, still farming their way.
- Forest Loss:
- Development is slowly destroying the rainforests.
- Every year, a big chunk of forest disappears.
- Rain washes away topsoil, turning green land into barren waste.
3. Life in the Ganga-Brahmaputra Basin
- Location:
- The Ganga and Brahmaputra rivers make this basin in India.
- It’s in the subtropical region, between 10°N and 30°N.
- Tributaries like Ghaghra, Son, Chambal, Gandak, Kosi (for Ganga), and others (for Brahmaputra) drain it.
- Features:
- Includes plains, Himalayan mountains, foothills, and Sundarbans delta.
- Ox-bow lakes are common in the plains.
- Climate:
- Monsoon brings rain from mid-June to mid-September.
- Summers are hot; winters are cool.
3.1 Population and Land
- Population Density:
- Number of people per square kilometre.
- Example: Uttarakhand has 189, West Bengal has 1029, Bihar has 1102.
- Where People Live:
- Mountains with steep slopes have fewer people because it’s tough to live there.
- Plains have lots of people due to flat, fertile land good for farming.
- Farming:
- Main job is farming because of flat land.
- Paddy (rice) is the top crop since it needs lots of water and rain is heavy.
- Other crops: Wheat, maize, sorghum, gram, millets.
- Cash crops: Sugarcane, jute.
- Banana plantations in some spots.
- Tea plantations in West Bengal and Assam.
- Silk comes from silkworms in Bihar and Assam.
- Terrace farming on gentle hill slopes.
3.2 Vegetation
- Types of Plants:
- Plains: Tropical deciduous trees like teak, sal, peepal, and thick bamboo in Brahmaputra area.
- Delta: Mangrove forests.
- Mountains: Coniferous trees like pine, deodar, fir in Uttarakhand, Sikkim, Arunachal Pradesh due to cool weather and steep slopes.
3.3 Wildlife
- Animals:
- Elephants, tigers, deer, monkeys are common.
- One-horned rhinoceros in Brahmaputra plain.
- Bengal tiger and crocodiles in the delta.
- Water Life:
- Fresh river waters, lakes, and Bay of Bengal have lots of fish like rohu, catla, hilsa.
- Rice and fish are the main food for people here.
- Special Animal:
- Susu (blind dolphin) lives in Ganga and Brahmaputra rivers.
- Shows if the river is healthy; pollution is killing it.
3.4 Case Study: Fisherman Binod
- Story:
- Binod lives in Malwali Maun village, Bihar.
- He and friends cleaned an ox-bow lake to grow fish.
- Lake weeds feed the fish.
- Around the lake, fertile land grows paddy, maize, pulses with buffalo ploughing.
- They catch enough fish to eat and sell to nearby towns.
- Community lives happily with nature unless town pollution spoils the lake.
3.5 Cities and Pollution
- Big Cities:
- Allahabad, Kanpur, Varanasi, Lucknow, Patna, Kolkata—all with over 10 lakh people—are on the Ganga.
- Pollution:
- Wastewater from cities and factories goes into rivers, making them dirty.
3.6 Transport
- Types:
- Roads and railways move people in plains.
- Rivers are good for water transport.
- Kolkata is a key port on the Hooghly River.
- Many airports in the plains.
3.7 Tourism
- Places to Visit:
- Taj Mahal on Yamuna in Agra.
- Allahabad where Ganga and Yamuna meet.
- Buddhist stupas in Uttar Pradesh and Bihar.
- Lucknow with Imambara.
- Assam’s Kaziranga and Manas for wildlife.
- Arunachal Pradesh for tribal culture.
4. Questions and Answers
4.1 Short Answer Questions
- Name the continent where the Amazon Basin is located?
- South America.
- What crops do Amazon Basin people grow?
- Tapioca, pineapple, sweet potato, manioc, coffee, maize, cocoa.
- Name birds in Amazon rainforests?
- Toucans, hummingbirds, macaws.
- What are major cities on the River Ganga?
- Allahabad, Kanpur, Varanasi, Lucknow, Patna, Kolkata.
- Where is the one-horned rhinoceros found?
- Brahmaputra plain.
4.2 Multiple Choice Questions
- Toucans are a type of:
- (a) Birds.
- Manioc is the staple food of:
- (c) Amazon.
- Kolkata is located on the river:
- (b) Hooghly.
- Deodars and firs are a type of:
- (a) Coniferous trees.
- Bengal tiger is found in:
- (b) Delta area.
4.3 Matching
- (i) Cotton textile → (e) Ganga plain
- (ii) Maloca → (d) Slanting roof
- (iii) Piranha → (g) Fish
- (iv) Silkworm → (c) Sericulture
- (v) Kaziranga → (a) Assam
4.4 Give Reasons
- Why are rainforests depleting?
- Development like roads and cutting trees is destroying them fast, and rain washes soil away.
- Why is paddy grown in Ganga-Brahmaputra plains ?
- Flat land and heavy rain make it perfect for paddy, which needs lots of water.
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