In the Expansive Plain Notes Class 9 Geography Chapter 2 Kerala Syllabus Questions and Answers

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Kerala Syllabus 9th Standard Social Science Geography Notes Chapter 2 In the Expansive Plain

Class 9 Social Science Geography Chapter 2 Notes Question Answer Kerala Syllabus In the Expansive Plain

Class 9 Geography Chapter 2 Notes Kerala Syllabus English Medium

Question 1.
Observe the map given below (North Indian Plains – Regional Division) and list out the rivers that flow through the Indo-Gangetic Brahmaputra Plain.

Answer:
Ganga,Yamuna ,Betwa ,Jhelum,Tenab, Ravi, Riyaz, Sutlej, Kali, Si, Ratwa, Takan Dasan, Dagamati. Ghaghra, Gandak, Dakasi, Brahmapupta, Tista, Manas, Yirang, Dalahit, Looney, Dibang, Lohit.

Question 2.
Rivers originating from the Himalayas are known as Himalayan rivers, while those originating from the peninsular plateaus are referred to as peninsular rivers. Categorize the rivers flowing through the Indo Gangetic Brahmaputra plain based on their place of origin as Himalayan rivers or Peninsular rivers, and list them accordingly.

Himalayan rivers	Peninsular rivers
Sindu, Jhelum, Chenab, Beas, Ravi, Sutlej, Kali, Ghaghara, Gandak, Koshi,Manas, Dibang,Lohith, Ganga (or the Ganges), Yamuna, and Brahmaputra.	Looni, Sind, Ken and Son

Question 3.
List the eastern and western boundaries of the North Indian Plains with the help of a physiographic map of India.
Answer:
Eastern boundaries of North Indian Plains upto Brahmaputra River and Western boundaries from Sindhu River.

Question 4.
Observe the map given below and list the four regional divisions of the North Indian Plain.

Answer:

• Rajasthan Plain
• Punjab- Haryana Plain
• The Ganga Plain
• Brahmaputra Plain

Question 5.
Locate the Aravali Mountain range with the help of a physiographic map of India.
Answer:

Question 6.
Find out the influence of the Aravali Mountain range in the climate of the Rajasthan Plain.
Answer:
Since the Aravali mountain lies parallel to the southwest monsoon winds in the south-west to east direction, the vapour-rich southwest monsoon winds do not cross the western side of the Aravali mountain. As a result, the western part of the Aravali mountain has become a dry region and the windward part has become a rainfed area. The Aravali mountain plays an important role in the biodiversity of Rajasthan.

Question 7.
Locate the significant landform to the west of the Punjab Haryana Plain by referring to an atlas.
Answer:
Rajasthan Plain

Question 8.
Based on geographical features, the Ganga Plain has been further divided into three regions. Upper Ganga Plain, Middle Ganga Plain, Lower Ganga Plain. Identify it in a Map.
Answer:

Question 9.
With the help of an atlas, identify and locate the Brahmaputra Plain in an outline map of India and include it in My Own Atlas.
Answer:

Question 10.
Observe the map given below and locate the major tributaries of the River Brahmaputra in the outline map of India. Include it in ‘My Own Atlas’.

Answer:

Question 11.
Prepare a digital album containing the pictures of river meandering and ox-bow lakes in different places of the world.
Answer:

Question 12.
Which one of the geographical divisions of the North Indian Plain is more suitable for agriculture?
Answer:
Alluvial Plains

Question 13.
Identify and list out the landforms that are formed due to the depositional process by rivers. Prepare a digital album containing pictures of such depositional landform features.
Answer:
Alluvial sediments are landforms formed as a result of the deposition process of a river, the Mianders, the oxbow lakes and Alluvial plains.

Question 14.
The North Indian Plain’s distance from the ocean contributes to the excessive heat experienced during the summer in these regions. Why is it so?
Answer:
As the distance increases, the amount of water vapour in the air decreases. As a result of this, the plains of northern India, situated far away from the sea, experience extreme heat during the summer season.

Question 15.
By observing the map given below, identify and list the two branches of the southwest monsoon winds. Try to understand their paths over the subcontinent.

Answer:

• The Arabian branch of the southwest monsoon winds.
• The Bay of Bengal branch of the southwest monsoon winds.

Question 16.
The rainfall received in Rajasthan from the southwest monsoon is very scanty. Why?
Answer:
The western parts of Rajasthan do not receive rain as the south-west monsoon winds, which cause rain in the plains of north India, pass parallel to the monsoon trough due to the location of the Aravali mountain ranges.

Question 17.
Identify the movement of winds that blow in the months of October and November. Locate them. in an outline map of India and include it in ‘My Own Atlas’.
Answer:

Question 18.
Locate the Sundarbans delta by referring to an atlas. With the help of information technology, prepare a note with pictures of the characteristic features of mangrove forests.
Answer:

The swamp forests are the natural vegetation found in the vast saline expanses of Rajasthan, freshwater lakes, the freshwater marshes of the Ganga Plain, the flood plains of the Brahmaputra, and the deltaic region of Sundarbans. The marshy and expansive deltaic region of Ganga Plain in West Bengal is Sundarbans.

The natural vegetation found luxuriously in this region is mangroves. This region serves as a natural habitat for the Royal Bengal Tiger. The roots of mangrove forests create a natural habitat for numerous aquatic species, including fishes. They are the abode of varied species of birds. Sundri, a type of mangrove, stands out as one of the distinctive features of the Sundarbans delta.

Question 19.
Identify and list the major natural vegetations in the North Indian Plain by analyzing the map.

Answer:

• The tropical Deciduous Forests
• The tropical Thron Forest
• Swamp Forests

Question 20.
Identify the distribution of different types of soils in the North Indian Plain by analysing the map given below and list them.

Answer:
Alluvial soil

• Red soil
• Forest Soil
• Laterite Soil
• Black Soil

Question 21.
Observe the table given below. In the table, the major crops cultivated in three different cropping seasons in the North Indian Plain are listed. Try to understand the duration of each cropping season and the crops cultivated in each season. Prepare a note on it by adding additional information with the help of information technology.

Cropping Seasons	Major Crops
Kharif (From June to September)	Tropical Crops- Rice, Cotton, Jute, Bajra, Tur, etc.
Rabi (From October to March)	Temperate-Subtropical Crops- Wheat, Gram, Mustard, Barely, etc.
Zaid (From April to June)	Vegetables, Fruits,Fodder etc.

Answer:
1. Rabi Season (Winter Season)

• Time Period: October to March
• Major Crops:
• Wheat: The primary staple crop, it is sown in November and harvested in March. The cool weather is ideal for its growth.
• Barley: Another important cereal crop, often grown in rotation with wheat.
• Gram (Chickpea): A significant legume that enriches the soil with nitrogen.
• Mustard: An essential oilseed crop that thrives in cooler temperatures.
• Peas: A valuable vegetable crop, often grown for both domestic consumption and market sales.

2. Kharif Season (Monsoon Season)

• Time Period: June to September
• Major Crops:
• Rice (Paddy): The dominant crop, requiring abundant water, is planted at the onset of monsoon and harvested in October.
• Maize: Grown for both grain and fodder, it benefits from the rainy season.
• Bajra (Pearl Millet): A drought-resistant crop well-suited to the semi-arid conditions of certain areas.
• Cotton: Cultivated in the well-drained soils of the region, crucial for the textile industry.
• Sugarcane: An important commercial crop, though it has a longer growing season, often overlapping with both Kharif and Rabi.

3. Zaid Season (Summer Season)

• Time Period: April to June
• Major Crops:
• Watermelon: Grown extensively due to its high water content, which makes it a popular summer fruit.
• Cucumber: Another summer favorite, cultivated for its refreshing properties.
• Moong (Green Gram): A short-duration pulse crop that enriches the soil and fits well between the Rabi and Kharif seasons.
• Pumpkin: Grown for both vegetable and ornamental purposes during the warm months. These cropping patterns reflect the adaptation to seasonal variations in temperature and rainfall in the North Indian Plain, optimizing agricultural productivity and sustainability.

In the Expansive Plain Class 9 Extended Activities

Question 1.
Project – ‘The significant role played by The North Indian Plain in shaping human life in India’.
Answer:
Introduction
The North Indian Plain, also known as the Indo Gangetic Plain, is one of the most fertile and densely populated regions in the world. Stretching across several Indian states, this vast plain has significantly influenced the development of human life in India, contributing to its cultural, economic, and social progress.

Geographical Overview

• Location: The North Indian Plain extends from the foothills of the Himalayas in the north to the Deccan Plateau in the south.
• States Covered: Punjab, Haryana, Uttar Pradesh, Bihar, West Bengal, and parts of Rajasthan and Assam.
• Major Rivers: The plain is primarily formed by the deposition of silt by rivers such as the Indus, Ganges, and Brahmaputra and their tributaries.

Economic Importance
Agriculture:

• Fertility: The alluvial soil is extremely fertile, supporting the cultivation of rice, wheat, sugarcane, and various other crops.
• Green Revolution: This region was the primary beneficiary of the Green Revolution in the 1960s, leading to increased agricultural productivity.

Industry:

• Textiles and Handicrafts: Traditional industries, including weaving and pottery, have flourished here due to the availability of raw materials.
• Modern Industries: Cities like Delhi, Kanpur, and Lucknow are industrial hubs, contributing significantly to India’s GDP.

Trade and Commerce:

• Trade Routes: Historically, the plain has been a major trade route, connecting various parts of India and facilitating commerce.
• Transport Infrastructure: Modern infrastructure, including roads, railways, and airports, is well-developed, enhancing trade and mobility.

Environmental Aspects

• Natural Resources:
• Water Resources: Abundant river systems provide water for irrigation, drinking, and other uses.
• Minerals: The region has some mineral resources, including natural gas and petroleum.

Challenges:

• Flooding: Annual monsoon rains often lead to floods, causing significant damage to life and property.
• Pollution: Industrial activities and agricultural runoff have led to pollution of rivers and soil degradation.
• Conservation Efforts:
• Sustainable Agriculture: Efforts are being made to promote sustainable farming practices to maintain soil health.
• River Cleaning Projects: Initiatives like the Namami Gange project aim to clean and rejuvenate the Ganges River.

Conclusion
The North Indian Plain has played a pivotal role in shaping human life in India. Its fertile land, historical significance, economic potential, and rich cultural heritage make it a cornerstone of Indian civilization. Understanding its contributions helps appreciate the complexity and diversity of human development in this region.

Question 2.
Conduct a seminar on the topic ‘Climate and Crops’.
Answer:
A. Introduction to Climate and Agriculture Understanding Climate

• Climate vs. Weather: Climate refers to longterm patterns and averages of meteorological conditions over extended periods (typically 30 years or more), while weather refers to shortterm conditions.
• Climate Zones: Different regions have varying climates (e.g., tropical, temperate, arid), affecting the types of crops that can be grown.

Role of Agriculture

• Agriculture is deeply intertwined with climate, relying on specific weather patterns for crop growth.
• Key climatic factors influencing agriculture include temperature, precipitation, and sunlight.

B. Impact of Climate Change on Crop Production Temperature Changes

• Increased Temperatures: Can lead to heat stress on plants, reduced yields, and altered growing seasons.
• Frost-Free Periods: Longer periods without frost can extend growing seasons but also affect the lifecycle of pests. Precipitation Patterns
• Changes in Rainfall: Altered rainfall patterns can lead to droughts or excessive flooding, both detrimental to crops.
• Water Availability: Changes in snowmelt and river flows impact irrigation systems.
  Extreme Weather Events
• Increased frequency and severity of storms, hurricanes, and other extreme weather events can devastate crops.
  CO₂ Levels
• Elevated CO₂ can enhance photosynthesis and growth in some crops but may also reduce the nutritional quality of others.

C. Case Studies of Climate Effects on Specific Crops
Wheat

• Heat Sensitivity: Wheat is particularly sensitive to high temperatures during flowering and grain-filling stages, which can reduce yields.
  Rice
• Flooding: Rice is highly susceptible to changes in water availability, with both drought and flooding posing significant threats.
• Temperature: Optimal growth occurs at specific temperature ranges, and deviations can affect productivity.
  Maize (Corn)
• Drought: Maize is vulnerable to drought, particularly during the flowering stage, impacting pollination and kernel development.
  Coffee
• Temperature and Pests: Coffee plants require stable temperatures, and climate change has increased the prevalence of pests like the coffee borer beetle.

D.Future Outlook and Technological

Innovations
Genetic Engincering

• CRISPR and other gene-editing technologies to develop crops with desired traits (e.g., drought tolerance, pest resistance).

Agroforestry

• Integrating trees and shrubs into crop systems to enhance biodiversity, improve soil health, and provide shade and wind protection.

Data Analytics

• Big data and machine learning to predict weather patterns, optimize planting schedules, and manage resources efficiently.

Global Collaboration

• International efforts and collaborations to share knowledge, resources, and innovations in agriculture and climate adaptation.

Question 3.
How is the formation of the North Indian Plains associated with the formation of the Himalayas? Elucidate.
Answer:
The formation of the North Indian Plains, also known as the Indo-Gangetic Plains, is closely associated with the formation of the Himalayas. This relationship is primarily driven by the tectonic activities involving the Indian Plate and the Eurasian Plate. Here’s how the two processes are connected:

A. Tectonic Plate Collision:

• Around 50 million years ago, the Indian Plate began its collision with the Eurasian Plate. This collision is a major tectonic event that led to the uplifting of the Himalayas.
• As the Indian Plate moved northwards and collided with the Eurasian Plate, the intense pressure and force caused the crust to buckle and fold, leading to the formation of the Himalayan mountain range.

B. Erosion and Sediment Deposition:

• The newly formed Himalayas were subjected to significant weathering and erosion due to climatic factors such as rainfall and glaciers.
• Erosion processes carried vast amounts of sediment from the mountains down to the plains. Rivers such as the Indus, Ganges, and Brahmaputra played a crucial role in transporting this eroded material.
• Over millions of years, these rivers deposited sediments over a vast area, creating the extensive alluvial plains known as the North Indian Plains.

C. Formation of the Plains:

• The sediments transported by the rivers settled in layers, gradually building up the plains. These alluvial deposits created the fertile soil characteristic of the IndoGangetic Plains.
• The continual deposition of sediments has led to the formation of one of the most extensive and fertile plains in the world.

D. River Systems and Drainage Patterns:

• The major river systems, originating in the Himalayas, carved out and shaped the plains. Their drainage patterns contributed to the distribution and depth of sediment deposits.
• Flooding and seasonal variations in river flow further influenced the sediment distribution, continuously shaping the landscape of the plains.

Question 4.
Draw the outline map of India and locate the divisions of the North Indian Plain. Exhibit it in your classroom.
Answer:

Question 5.
Draw the outline map of India and locate the major physiographic divisions using different colours to distinguish them. Also, draw the rivers flowing through the North Indian Plain and display the map in your classroom.
Answer:

Std 9 Geography Chapter 2 Notes Kerala Syllabus Extra Question Answer

Question 1.
What are the four main divisions of the Northern Indian Plains?
Answer:
The four main divisions of the Northern Indian Plains are the Punjab – Haryana Plains, Rajasthan Plains, the Ganga Plains, and the Brahmaputra Plains. These divisions are based on the river systems and the regions they cover.

Question 2.
What is called Doab? Give any two examples.
Answer:
A doab is a land lying between two rivers that join together later. For Example: Bari Doab Between the rivers Beas and Ravi.Rachna Doab – Between the rivers Ravi and Chenab.

Question 3.
Explain the reasons for the occurrence of various landforms on the earth’s surface.
Answer:
A variety of landforms on the Earth’s surface are caused by the constant action of external forces acting on the Earth’s surface, such as flowing water, wind, glaciers, and waves.

Question 4.
Explain the Four divisions of Northern Indian Plains?
Answer:
This extensive alluvial plain is also known as the Indo-Gangetic-Brahmaputra Plain and the North Indian Plains. The plain can be divided into four regional divisions: the Rajasthan Plain, the Punjab-Haryana Plain, The Ganga Plain and the Brahmaputra Plain.

Rajasthan Plain

• The Rajasthan Plain, which includes the Thar Desert, marks the westernmost end of the North Indian Plain.
• Two-thirds of the Thar Desert is situated in Rajasthan, while the remaining portion extends into the neighbouring states of Haryana, Punjab, and Gujarat.
• The Thar Desert is further divided into two significant regions: the actual desert area called Marusthali (the desert proper) and the semi-arid plain (semi-desert region) known as Rajasthan Bagar.
• The Rajasthan Plain is situated to the west of the Aravali Mountain range.

Punjab-Haryana Plain

• The Punjab-Haryana Plain is situated to the east and northeast of the Rajasthan Plain.
• This plain is the western part of the North Indian Plain and extends upto the Yamuna River.
• The Punjab Plain, a significant part of this region, is primarily formed by the deposition of sediments carried by rivers such as Satluj, Jhelum, Chenab, Ravi and Beas.

The Ganga Plain

• The division of the plain situated to the east of the Punjab-Haryana Plain is known as the Ganga Plain.
• The Ganga Plain stretches from Bangladesh in the east to the Yamuna River in the west.

Brahmaputra Plain

• The Brahmaputra Plain, known by various names such as Brahmaputra Valley, Assam Valley, and Assam Plain, constitutes the easternmost part of the North Indian Plain.
• Stretching from the easternmost edge of Assam to the west of Dubri, near the border of Bangladesh, it spans approximately 720 km in length, with the width ranging from 60 to 70 km .
• The major portion of the Brahmaputra Plain is located in the state of Assam.

Question 5.
What is Deposition?
Answer:
Deposition is the process by which rock material, which is crushed by physical, chemical and biological processes, is transported from one place to another by these external forces and deposited in low-lying areas.

Question 6.
Which rivers primarily define the Punjab Plains?
Answer:
The Punjab Plains are primarily defined by the five rivers of the Indus system: Jhelum, Chenab, Ravi, Beas, and Sutlej.

Question 7.
Describe the process of Formation of Indo -Gangetic- Brahmaputra.
Answer:

• Various types of landforms, such as lofty mountains, expansive plains, plateaus, scorching deserts and valleys, are found on the surface of the Earth. They were formed over millions of years.
• The physical division that lies between the south of the Northern Mountains and to the north of the Peninsular Plateau is known as the Northern Indian Plains.
• This extensive alluvial plain is also known as the Indo-Gangetic-Brahmaputra Plain and the North Indian Plains.
• Diverse landforms are formed on the surface of the Earth through the continuous processes driven by external forces, such as running water, wind, glaciers, and waves that operate on the Earth’s surface. Therefore, these external forces are called geomorphic agents, and the processes that lead to the formation of landforms are called geomorphic processes.

• The sediments or rock materials formed through the disintegration of rocks by various physical, chemical, and biological processes are transported by these external forces or geomorphic agents from one place to another.
• These materials are then deposited conveniently in low-lying regions. This process is called deposition.

• Rivulets originating from high altitudes form rills, and they join together to form streams.
• Rivers originating from high altitudes transport sediments down the stream and deposit them in low-lying areas. Over time, the deposition of sediments by rivers creates numerous depositional landforms, including expansive alluvial plains.
• The average depth of alluvial deposits in this plain ranges from 1000 metres to 2000 metres.
• The Indo-Gangetic-Brahmaputra Plain, extending approximately 3200 km from the mouth of River Indus to the mouth of River Ganga, is one of the largest alluvial plains in the world.
• It spreads over around 2400 km in India.
• The plain widens from east to west, with the width varying between 150 km and 300 km.
• This plain is bordered by the Shiwalik ranges in the north and the irregular edges of the Peninsular Plateau in the south.

• The plain can be considered a single physiographic unit, and it is based on the river system, the direction of the flow of rivers and topographical features.

Question 8.
Explain the four regional divisions of the North Indian Plain.
Answer:
The plain can be divided into four regional divisions:

• Rajasthan Plain
• Punjab-Haryana Plain
• The Ganga Plain
• Brahmaputra Plain

Rajasthan Plain

• The Rajasthan Plain, which includes the Thar Desert, marks the westernmost end of the North Indian Plain.
• Two-thirds of the Thar Desert is situated in Rajasthan, while the remaining portion extends into the neighbouring states of Haryana, Punjab, and Gujarat.
• The Thar Desert is further divided into two significant regions: the actual desert area called Marusthali (the desert proper) and the semi-arid plain
  (semi-desert region) known as Rajasthan Bagar.
• The Rajasthan Plain is situated to the west of the Aravali Mountain range.
• A significant river in this plain is the Luni, which is non-perennial in nature.
• There are numerous salt lakes in Rajasthan Plain, and some of the major salt lakes are Sambhar, Didwana, and Sargol.

Punjab-Haryana Plain

• The Punjab-Haryana Plain is situated to the east and northeast of the Rajasthan Plain.
• This plain is the western part of the North Indian Plain and extends upto the Yamuna River.
• The eastern border of this plain is defined by the River Yamuna.
• In India, this plain extends over the states of Punjab, Haryana, and Himachal Pradesh, covering an area of approximately 1.75 lakh sq. km. It gently slopes towards the west.
• The Punjab Plain, a significant part of this region, is primarily formed by the deposition of sediments carried by rivers such as Satluj, Jhelum, Chenab, Ravi and Beas.
• Punjab is etymologically known as the Land of Five Rivers.
• A doab is a land lying between two rivers that join together later.
• Punjab-Haryana Plain is divided into five major doabs.

The Ganga Plain

• The division of the plain situated to the east of the Punjab-Haryana Plain is known as the Ganga Plain.
• The Ganga Plain stretches from Bangladesh in the east to the Yamuna River in the west.
• This expansive plain covers the states of Uttarakhand, Uttar Pradesh, Haryana, Delhi, and parts of Jharkhand and West Bengal, spanning an area of approximately 3.75 lakh sq.km.
• This expansive plain was formed through the depositional processes by the River Ganga and its tributaries.
• The average elevation of the Ganga Plain is around 200 metres above mean sea level, and it exhibits a general slope towards the east and the southeast.

Brahmaputra Plain

• The Brahmaputra Plain, known by various names such as Brahmaputra Valley, Assam Valley, and Assam Plain, constitutes the easternmost part of the North Indian Plain.
• Stretching from the easternmost edge of Assam to the west of Dubri, near the border of Bangladesh, it spans approximately 720 km in length, with the width ranging from 60 to 70 km.
• The major portion of the Brahmaputra Plain is located in the state of Assam.
• The Eastern Himalaya in the north, the PatkaiNaga Hills in the east, and the Garo-Khasi Jaintia Hills and Mikir Hills in the south serve as their natural boundaries, separating the plain from the surrounding areas.
• The Lower Ganga Plain lies to the west of the Brahmaputra plain.
• The Brahmaputra Plain, spanning an area of approximately 56,275 sq.km, is formed through the depositional processes carried out by the Brahmaputra River and its tributaries. Teesta, Manas, Lohit and Dibang are some of the major tributaries of the Brahmaputra River.
• When rivers enter a plain from mountainous regions, their velocity decreases abruptly, and the sediments (alluvium) carried by the rivers get deposited in the form of fans. These depositional landform features are referred to as alluvial fans.

• Rivers that continue flowing through plains split into many channels. As the river’s velocity

• A river thus flowing in a sinuous manner is called river meandering.

Question 9.
Explain the major three zones of North Indian Plain?
Answer:

• The North Indian Plain can be divided into three zones from north to south based on its geomorphic features. They are:
  1. Bhabar
  2.Tarai
  3. Alluvial plains
• Bhabar: It is a narrow belt, approximately 8 to 10 km wide, running parallel to the Shiwalik mountain range at the break-up of the slope.
• It is situated to the south of the Shiwalik mountain range along its foothills.
• This zone of the plain is formed by the deposition of rocks and boulders brought by rivers flowing from the mountains.
• The rivers flowing through this region are not visible as they flow beneath the rocks and boulders.
• Tarai: The Tarai is a marshy and swampy tract, approximately 10 to 20 km wide, running parallel to the Bhabar belt.
• The rivers that disappear in the Bhabar region re-emerge in this area.
• The Tarai has a luxurious growth of natural vegetation and serves as a habitat for varied wildlife.
• Alluvial plains: To the south of the Tarai, the belt consisting of older and newer alluvial deposits forms the Alluvial plain.
• The older alluvium deposits are called the Bhangar, and the newer ones are referred to as the Khadar.
• The major characteristic features of this region include depositional landforms such as riverine islands, sandbars, and deltas.
• Braided streams, meanders and ox-bow lakes are also prominent features of this area.

Question 10.
What are geomorphic agents and geomorphic processes?
Answer:
Diverse landforms are formed on the surface of the Earth through the continuous processes driven by external forces, such as running water, wind, glaciers, and waves that operate on the Earth’s surface. Therefore, these external forces are called geomorphic agents, and the processes that lead to the formation of landforms are called geomorphic processes.

Question 11.
Describe the Monsoon Season in North Indian Plain.
Answer:
Northeast Monsoon:

• The low-pressure area that prevails over the North Indian Plain starts moving southward in response to the apparent movement of the sun towards the southern hemisphere.
• This season is named the retreating monsoon season.
• During this period, a high-pressure area develops over the North Indian Plain, and consequently, the wind starts blowing from here to the Indian Ocean.
• As these moisture-less winds blow from the northeast, this season is called the northeast monsoon season.
• The North Indian Plain generally experiences a dry climate during this season. Owing to the conditions of high temperature and atmospheric humidity, the weather becomes rather oppressive. This phenomenon is commonly known as the ‘October heat’.

Question 12.
Explain the Cold Weather season.
Answer:

• The cold weather season sets in by mid November in North India.
• December and January are the coldest months in the North Indian Plain, and excessive cold is experienced during this period.
• The major reasons for excessive cold weather in the North Indian Plain are: The major portion of the North Indian Plain is located far away from the moderating influence of the oceans, resulting in a continental climate,snowfall in the nearby
• Himalayan ranges contributes to strong cold waves,Cold winds from West Asia cause frost, fog and coldwaves in the western part of the North Indian Plain. The apparent movement of the sun from the northern hemisphere towards the southern hemisphere adds to the cold conditions.
• During the cold weather season, the North Indian Plain receives slight rainfall.

Question 13.
What is called ‘Loo’
Answer:
Hot, dry and oppressive wind blows from the desert region of Rajasthan to the Ganga Plain in the months of May and June this wind is called ‘Loo’.

Question 14.
Explain the direction of the Southwest Monsoon in North Indian Plains?
Answer:
Southwest Monsoon Season:

• The southwest monsoon season, experienced from June to September, is the main rainy season in the North Indian Plain.
• The southwest monsoon winds enter the Indian subcontinent as two branches.
• The Bay of Bengal branch, entering the land through the Sundarbans delta region, gets bifurcated into two sub-branches.
• One branch moves eastward and enters the Brahmaputra Plain, causing widespread rains, the other branch, moving westward along the Ganga Plain, causes rainfall in West Bengal, Bihar, Uttar Pradesh, and Delhi and proceeds further westward.
• The Punjab Plain this branch joins the Arabian branch which is moving parallel to the Aravali.
• Mountains and then brings rain to the foothills of the Western Himalayas.

Question 15.
What are the two divisions of Tropical deciduous forest?
Answer:
The Tropical deciduous forests are divided into two. They are the dry deciduous forests and the moist deciduous forests.

Question 16.
Describe a Tropical deciduous forest.
Answer:

• The Tropical deciduous forests are further divided into two. They are the dry deciduous forests and the moist deciduous forests.
• Dry deciduous forests are found in those regions where the annual rainfall ranges between 70 cm and 100 cm.
  
• In these forests, trees shed their leaves for approximately 6 to 8 weeks in the dry season when sufficient moisture is not available.
• The dry deciduous forests are found in the plains of Uttar Pradesh and Bihar.
• Moist deciduous forests are found in areas with moderate rainfall, ranging from 100 cm to 200 cm per annum.
  
• They are mainly seen along the strip of the Shiwalik range, including Tarai and Bhabar, and in certain parts of Odisha and West Bengal.
• Teak, sal, shisham, mahua, amla and sandalwood are the main species of the tropical deciduous forests.

Question 17.
Explain Tropical Thron Forest.
Answer:

• Tropical thorn forests are prevalent- in the semi-arid areas of southwest Punjab, Haryana, Rajasthan, and Uttar Pradesh.
• These forests consist of various grasses and shrubs, with important species such as babool, ber, wild date palm, khair, neem, khejri and palas.
• In certain regions Tussocky grass grows as undergrowth, reaching up to a height of 2 metres.

Question 18.
Explain Swamp Forests.
Answer:

• The swamp forests are the natural vegetation found in the vast saline expanses of Rajasthan, freshwater lakes, the freshwater marshes of the Ganga Plain, the flood plains of the Brahmaputra, and in the deltaic region of Sundarbans.
• The marshy and expansive deltaic region of Ganga Plain in West Bengal is Sundarbans.
• The natural vegetation found luxuriously in this region is mangroves.
• This region serves as a natural habitat for the Royal Bengal Tiger
• The roots of mangrove forests create a natural habitat for numerous aquatic species, including fishes.
• Sundri, a type of mangrove, stands out as one of the distinctive features of the Sundarbans delta.

Question 19.
Name the different types of soil in the North Indian Plain?
Answer:

• Alluvial Soil
• Red Soil
• Arid Soil

Question 20.
Explain Alluvial Soil?
Answer:
Alluvial soil

• The soil which is widespread in the North Indian Plain is alluvial soil.
• The alluvial soils vary in nature from sandy loam to clay.
• Alluvial soil is found in limited areas of Rajasthan and extensively in the plains of Gujarat. There are two different types of alluvial soils developed in the Ganga Plain: Khadar and Bhangar.
• The alluvial soil in the lower and middle Ganga plains and the Brahmaputra Valley are more loamy and clayey.
• Alluvial soil is well-suited for agriculture.

Question 21.
Name the soil found in the Sundarbans delta?
Answer:
Saline Soil

Question 22.
Write a short note on Saline Soil?
Answer:
The soil found in the Sundarbans delta region is saline soil which is characterised by a higher presence of salt. Saline soil consists of sand and loam. Seawater intrusions into the deltas cause the formation of saline soils. In certain areas of the North Indian Plain, where there is intensive cultivation with excessive irrigation, the fertile alluvial soil has turned saline.

Question 23.
Explain Arid Soil.
Answer:
Arid soil

• Arid soil is the soil extensively found in the western parts of the North Indian Plain, including Rajasthan.
• It is generally sandy and saline in structure.
• As this soil lacks humus and moisture, irrigation support is required for the plants to grow.

Question 24.
What significant contribution did the North Indian Plain make to the development of India’s agriculture-based economic system?
Answer:
The North Indian Plain plays a very significant role in building India’s economic system based on the agricultural sector. Wheat, rice, jute, and sugarcane are widely cultivated here. Extensive cultivation, supported by irrigation, has made this plain the granary of India. The entire plain, except the Thar Desert, has a well-developed network of roads and railways. This infrastructural development has facilitated largescale industrialisation and urbanisation of the region.

Question 25.
Which crop cultivated in between June to September?
Answer:
Rice (Paddy), Maize, Bajra (Pearl Millet), Cotton and Sugarcane.

Question 26.
Which crops cultivated in Rabi season?
Answer:
Wheat, Barley, Gram (Chickpea), Mustard and Peas

Question 27.
Which of the following is Zaid crop of North Indian Plain?

• Rice
• Maize
• Bajra
• Pumpkin

Answer:
Pumpkin