Class 9 Geography Chapter 1 HOTS Questions - Contemporary India - I

Q171. From where does the river Krishna originate and name its tributaries?
Ans: The Krishna river originates from a spring near Mahabaleshwar. It flows approximately 1,400 km before reaching the Bay of Bengal. Some of its main tributaries include:

• Tungabhadra
• Koyna
• Ghatprabha
• Musi
• Bhima

Q172. State some economic benefits of rivers and lakes.
Ans: Economic benefits of rivers and lakes include:

• Water from rivers is essential for various human activities.
• Riverbanks have historically attracted settlers, leading to the growth of large cities.
• Rivers are vital for irrigation, navigation, and hydro-power generation, especially in agricultural countries like India.
• Lakes promote tourism and provide recreational opportunities.
• Throughout history, rivers have played a fundamental role in human development.

Q173. Discuss the significant differences between the Himalayan and the Peninsular rivers.
Ans: Himalayan rivers:

• These rivers are perennial, meaning they flow all year round.
• They receive water from glacial melt and rainfall.
• They have long and deep courses.
• In their upper courses, they engage in erosional activity and carry large amounts of silt and sand.
• They feature large drainage basins.
• At their mouths, they create well-developed deltas. Examples include the Ganga and Brahmaputra.

Peninsular rivers:

• These rivers are seasonal, flowing only during certain times of the year.
• They primarily depend on rainfall and often dry up in the dry season.
• They have shorter and shallower courses.
• They carry less or no silt and sand.
• They have comparatively smaller drainage basins.
• They form smaller deltas, and some create estuaries. Examples include the Godavari and Narmada.

Q174. Compare the East flowing and West flowing rivers of the Peninsular plateau.
Ans: East Flowing Rivers:

• Originate from the Western Ghats and flow eastwards.
• Form deltas at their mouths.
• Drain into the Bay of Bengal.
• Have a large volume of water. Examples include Mahanadi, Godavari, Krishna, and Kaveri.

West Flowing Rivers:

• Originate in Central India and flow westwards.
• Form estuaries as they flow from rift valleys.
• Drain into the Arabian Sea.
• Have a lesser volume of water. Notable examples are Narmada and Tapi.

Q175. What are the main causes of the pollution in the rivers of India? How can we prevent this kind of pollution? 
Ans: Main Causes of Pollution in Indian Rivers:

• The increasing demand for water from domestic, municipal, industrial, and agricultural sources negatively impacts water quality.
• Excessive water extraction from rivers leads to a decrease in their volume.
• Untreated sewage and industrial waste are often discharged directly into rivers, harming both water quality and the rivers' ability to cleanse themselves.
• Urbanisation and industrialisation hinder the natural purification processes, causing pollution levels to rise.

How to Prevent Pollution:

• Industries must treat their effluents before releasing them into rivers.
• Residents living near rivers should be educated about the impacts of pollution and the challenges of cleaning contaminated water.
• Religious practices that involve immersing idols and other items in rivers should be regulated to reduce pollution.

Q176. What are the main causes of pollution of Indian rivers?
Ans: The main causes of pollution in Indian rivers include:

• Increased demand for water from domestic, municipal, industrial, and agricultural sources, which impacts water quality.
• Excessive water extraction reduces the volume of rivers.
• A significant amount of untreated sewage and industrial waste is discharged into rivers.
• This pollution harms water quality and diminishes the river's self-cleansing ability.
• Rapid urbanisation and industrialisation have further escalated pollution levels.

Q177. What types of lakes are found in India? Give suitable examples.
Ans: India is home to various types of lakes, each differing in size and characteristics. Lakes can be classified into three main categories:

• Saltwater Lakes:These lakes are typically found in coastal areas and can be formed by natural processes like spits and bars. Examples include:
  • Chilika Lake
  • Pulicat Lake
  • Kolleru Lake
  • Sambhar Lake
  • - located in Rajasthan, it is used for salt production.
• Freshwater Lakes:Most of these lakes are located in the Himalayan region and are of glacial origin. They are formed when glaciers carve out basins that later fill with meltwater. Notable examples include:
  • Wular Lake - the largest freshwater lake in India, situated in Jammu and Kashmir.
  • Dal Lake
  • Bhimtal
  • Nainital
  • Loktak Lake
  • Barapani
• Man-made Lakes:These lakes are created through the damming of rivers, primarily for hydropower generation and flood control. Examples include:
  • Guru Gobind Sagar (Bhakra Nangal Project)
  • Nizam Sagar
  • Nagarjuna Sagar
  • Rana Pratap Sagar

Lakes play a crucial role in regulating river flow, preventing flooding during heavy rains, and providing water during dry seasons.

Q178. What are the benefits of lakes to human beings?
Ans: Lakes provide numerous benefits to human beings:

• Flood Control: Lakes help regulate river flow, preventing flooding during heavy rains.
• Water Supply: They maintain a steady flow of water during dry seasons.
• Hydropower Generation: Lakes can be used to develop hydropower, providing renewable energy.
• Climate Regulation: Lakes moderate the local climate, contributing to a more stable environment.
• Aquatic Ecosystem: They support diverse aquatic life, maintaining ecological balance.
• Tourism and Recreation: Lakes enhance natural beauty, attracting tourists and offering recreational activities like boating and swimming.

In summary, lakes are vital for environmental stability, energy production, and enhancing human quality of life.

Q179. Give characteristics of the Ganga-Brahmaputra River System.
Ans: The Ganga-Brahmaputra River System has several key characteristics:

• The basin is separated from the Indus River basin by the Ambala watershed.
• It spans the central and eastern parts of the northern alluvial plains in Haryana, Uttar Pradesh, West Bengal, and Assam.
• The main river, the Ganga, and its tributaries drain the central part of the basin.
• The Ganga plain generally slopes from the north-west to the south-east, flowing into the Bay of Bengal.
• The eastern region is drained by the Brahmaputra, which flows from the north-east to the south-west and then south into Bangladesh.

Q180. Write main features of Indus Basin.
Ans: Main Features of the Indus Basin:

• The Indus River originates in Tibet, near Lake Mansarovar.
• It flows westward, entering India in the Ladakh district of Jammu & Kashmir, where it forms a scenic gorge.
• The river passes through Baltistan and Gilgit, emerging from the mountains at Attock.
• Its major tributaries—the Satluj, Beas, Ravi, Chenab, and Jhelum—join the Indus near Mithankot in Pakistan.
• Continuing south, the Indus eventually reaches the Arabian Sea, east of Karachi.
• With a total length of 2,900 km, the Indus is one of the longest rivers in the world.

Q181. Give main characteristics of the Ganga River System.
Ans: Main Characteristics of the Ganga River System

• The Ganga's headwaters, known as Bhagirathi, originate from the Gangotri Glacier and merge with the Alaknanda at Devaprayag in Uttarakhand.
• At Haridwar, the Ganga flows from the mountains into the plains.
• Its tributaries often flood parts of the northern plains, causing damage but also enriching the soil for agriculture.
• The river flows eastward until Farakka in West Bengal, which is the northernmost point of the Ganga delta.
• From here, the river splits; the Bhagirathi-Hooghly distributary flows south to the Bay of Bengal, while the main river continues into Bangladesh, joining the Brahmaputra and then known as the Meghna.
• This mighty river system flows into the Bay of Bengal, forming the Sundarban Delta.

Did You Know?

• The Sundarban Delta is named after the Sundari tree, which thrives in marshy areas.
• It is the world's largest and fastest-growing delta and is home to the Royal Bengal tiger.

Q182. What are the main characteristics of the mighty river Brahmaputra?
Ans: Main Characteristics of the Brahmaputra River

• The Brahmaputra originates in Tibet, east of Mansarovar Lake, near the sources of the Indus and Satluj rivers.
• It is slightly longer than the Indus, with most of its course flowing outside India.
• In Tibet, the river carries less water and silt due to the cold, dry climate.
• As it enters India, it flows through a region with high rainfall, increasing its water and silt volume.
• The river has a braided channel throughout Assam, creating many riverine islands.
• During the rainy season, the Brahmaputra often overflows, causing severe flooding in Assam and Bangladesh.
• Unlike other northern Indian rivers, the Brahmaputra has significant silt deposits on its bed, which raises the riverbed and leads to frequent channel shifts.

Q183. Write down the differences between a delta and an estuary.
Ans: 
Delta:

• A delta is a triangular-shaped landform at the mouth of a river where it meets the sea.
• It forms as the river deposits silt and splits into smaller channels called distributaries.
• Deltas extend into the sea and continuously grow seawards.
• The sea in a delta region is typically shallow, and tidal currents are weak, allowing sediment to accumulate.
• The world's largest and fastest-growing delta is the Ganga-Brahmaputra delta, also known as the Sunderban delta. Other significant deltas are formed by rivers like the Mahanadi, Godavari, Krishna, and Kaveri.

Estuary:

• An estuary is an inlet created by the submergence of a river's mouth.
• It has a single channel with steep banks, and the sea is generally deeper in estuarine areas.
• Strong tidal waves can wash away sediments deposited by the river.
• Estuaries often feature an indented coastline and serve as natural harbours, improving navigation.
• Examples of estuaries include the mouths of the Narmada and Tapi rivers.

Q184. Give main characteristics of the largest peninsular river.
Ans: The Godavari is the largest peninsular river in India.

• It has a length of approximately 1500 km.
• The river's drainage basin is the largest among peninsular rivers, covering parts of:
  • Maharashtra (about 50% of the basin area)
  • Madhya Pradesh
  • Odisha
  • Andhra Pradesh
• The Godavari is fed by several tributaries, including:
  • Purna
  • Wardha
  • Pranhita
  • Manjra
  • Wainganga
  • Penganga
• The last three tributaries are particularly large.
• Due to its significant length and extensive area, it is often referred to as the 'Dakshin Ganga'.

Q185. How Indian lakes differ from each other?
Ans: India is home to a variety of lakes, each differing in size and characteristics. Key differences include:

• Permanent vs Seasonal: Most lakes are permanent, while some, like those in semi-arid regions, only hold water during the rainy season.
• Formation:Lakes can form through various processes:
  • Glacial Action: Some lakes result from glaciers and ice sheets.
  • Wind and River Action: Others are shaped by wind or river activities.
  • Human Activities: Lakes can also be created by damming rivers, such as Guru Gobind Sagar.
• Types of Lakes:
  • Ox-bow Lakes: Formed by meandering rivers creating cut-offs.
  • Lagoons: Coastal lakes formed by spits and bars, like Chilika and Pulicat.
  • Saltwater Lakes: For example, Sambhar Lake in Rajasthan is known for salt production.
• Freshwater Lakes: Most are found in the Himalayan region, originating from glacial activity, such as Wular Lake, the largest freshwater lake in India.

Overall, the diversity of lakes in India reflects a range of natural processes and human influences.

Q186. Define the role of rivers in Indian economy.
Ans: Rivers play a vital role in the Indian economy through various means:

• Water Resource: Rivers provide essential water for drinking, agriculture, and industry.
• Agricultural Support: They are crucial for irrigation, supporting the majority of India's farming activities.
• Transportation: Rivers facilitate navigation, allowing for the movement of goods and people, which boosts trade.
• Hydropower Generation: Many rivers are harnessed for hydroelectric power, contributing to energy needs.
• Urban Development: Settlements along riverbanks have evolved into major cities, enhancing economic growth.
• Tourism: Rivers attract tourists, promoting local economies through recreational activities.

However, the increasing demand for water has led to pollution issues, affecting river health and quality. Initiatives like the National River Conservation Plan aim to improve water quality and restore these vital resources.

Q187. Which one of the following lakes is a salt water lake?
a) Sambhar
b) Wular
c) Dal
d) Pushkar
Ans: A

The Sambhar Lake in Rajasthan is known for its saline water, making it a salt water lake. The other options are freshwater lakes.

Q188. In which of the following places do the Bhagirathi and Alaknanda rivers join?
a) Devaprayag
b) Sanguan
c) Brahmagiri
d) Hrishikesh
Ans: A

The Bhagirathi and Alaknanda rivers meet at Devaprayag, which is known for this confluence. The other locations do not represent this joining.

Q189. At what place do the Ganga and Yamuna rivers have their confluence?
a) Allahabad
b) Haridwar
c) Kolkata
d) Dehradun
Ans: A

The Ganga and Yamuna rivers converge at Allahabad, also known as Prayagraj, making it a significant religious site. The other options do not represent this confluence.

Q190. Brahmaputra enters India in the state of:
a) Assam
b) Arunachal Pradesh
c) Sikkim
d) Manipur
Ans: B

The Brahmaputra river enters India through Arunachal Pradesh, flowing through the northeastern states. Assam is downstream of its entry point.

Q191. Which river is known as 'Dakshin Ganga'?
a) Godavari
b) Krishna
c) Kaveri
d) Gandak
Ans: A

The Godavari is referred to as 'Dakshin Ganga' due to its significance and size in southern India, while the other rivers do not hold this title.

Q192. Describe the journey of river Ganga in India and which rivers join it en route.
Ans: The journey of the Ganga River in India is remarkable and involves several key stages:

• The Ganga originates from the Gangotri Glacier and is initially known as Bhagirathi.
• At Devaprayag in Uttarakhand, it is joined by the Alaknanda.
• Upon reaching Haridwar, the Ganga enters the plains, where it begins to transport and deposit sediments.
• Major tributaries from the Himalayas include:
  • Yamuna - Joins the Ganga at Allahabad as a right bank tributary.
  • Ghaghra, Gandak, and Kosi - All originate from the Nepal Himalayas and contribute to the Ganga.
• These rivers often flood the northern plains, causing damage but also enriching the soil for agriculture.
• From the peninsular uplands, the Ganga receives tributaries such as:
  • Chambal
  • Betwa
  • Son
• Enlarged by these tributaries, the Ganga flows eastwards until it reaches Farakka in West Bengal, the northernmost point of the Ganga Delta.
• At Farakka, the river bifurcates:
  • The Bhagirathi-Hooghly flows southwards through the deltaic plains to the Bay of Bengal.
  • The mainstream continues south into Bangladesh, where it merges with the Brahmaputra and is known as the Meghna.
• This confluence forms the Sundarbans Delta, the largest delta in the world, marking the end of the Ganga's journey.

Q193. Have you heard about'Dakshin Ganga'? Give an account of its course.
Ans: Dakshin Ganga refers to the River Godavari, which is the largest peninsular river in India.

• It originates from the slopes of the Western Ghats in the Nasik district of Maharashtra.
• The river stretches approximately 1,500 km and flows into the Bay of Bengal.
• It has the largest drainage basin among peninsular rivers, covering parts of:
  • Maharashtra
  • Madhya Pradesh
  • Odisha
  • Andhra Pradesh
• The Godavari is fed by several tributaries, including:
  • Purna
  • Wardha
  • Pranhita
  • Manjra
  • Wainganga
  • Penganga
• Due to its significant length and extensive coverage, it is often referred to as the Dakshin Ganga.