96) What do Himalayan rivers do in their upper course?
Answer: The Himalayan rivers perform intensive erosional activity in their upper courses and carry huge loads of silt and sand.
97) What do Himalayan rivers do in the middle and lower course?
Answer:In the middle & lower courses these rivers form meanders, ox-bow lakes and many other depositional features in their flood plains. They also have well developed deltas.
98) Which river has the largest basin in India?
99) How dendritic pattern is formed by the river?
Answer:The dendritic pattern develops where the river channel follows the slope of the terrain. The stream with its tributaries resembles the branches of a tree, thus, the name dendritic is given.
100) How is Trellis Pattern developed by a river?
Answer:A river joined by its tributaries, at approximately right angles, develops a trellis pattern. A trellis drainage pattern develops where hard and soft rocks exist parallel to each other.
101) How is rectangular drainage pattern formed?
Answer: A rectangular drainage pattern develops on a strongly jointed rocky terrain.
102) When does a Radial pattern of drainage develop?
Answer: The radial pattern develops when streams flow in different directions from a central peak or dome like structure.
103) Why are Peninsular rivers called seasonal?
Answer: A large number of peninsular rivers are seasonal as their flow is dependent on rainfall and even the large rivers have reduced flow of water in the dry season.
104) Name the rivers which originate in Central Highlands & flow towards the west.
Answer:Rivers Narmada and Tapi.
105) What is a river system?
Answer:A river alongwith its tributaries may be called a river system.
106) From where does river Indus originate?
Answer:River Indus originate in Tibet, near Lake Mansarowar.
107) Name the tributaries which join Indus in Kashmir.
Answer:The Zaskar, the Nubra, the Shyok and the Hunza are the tributaries which join river Indus in the Kashmir region.
108) Which are the main tributaries of river Indus?
Answer:The Satluj, the Beas, the Ravi, the Chenab and the Jhelum are the main tributaries of river Indus.
109) What is the total length of river Indus?
Answer:It is about 2,900 kms.
110) In which states of India, Indus Basin is located?
Answer:In India in the states of Jammu & Kashmir, Himachal Pradesh and Punjab, the Indus basin is located.
111) What are the regulations of Indus Water Treaty of I960?
Answer:According to the regulations of the Indus Water Treaty(1960), India can use only 20 percent of the total water carried by Indus river system.
112) From which place does river Ganga originate?
Answer:The head waters of the Ganga, called the 'Bhagirathi' is fed by the Gangotri Glacier & joined by the Alaknanda at Devaparyag in Uttarakhand.
113) Name the main tributaries of the river Ganga.
Answer: The Yamuna, the Ghaghara, the Gandak and the Kosi are the main tributaries of river Ganga.
114) Which rivers rise from Nepal Himalaya?
Answer:The Ghaghara, the Gandak and the Kosi rise in the Nepal Himalaya.
115) Which tributaries join Ganga from peninsulas uplands?
Answer: The Chambal, the betwa and the son are the tributaries.
116) How is Sunderban Delta formed?
Answer: The waters of two mighty rivers ? the Ganga and the Brahmaputra flows into the Bay of Bengal and the delta formed by these rivers is known as Sunderban Delta. It is world's largest delta.
117) How is Sunderban Delta named?
Answer: The Sunderban delta has derived its name from Sundari trees which grow well in marshland.
118) What is the total length of the river Ganga?
Answer:The total length of the river Ganga is 2,500 km.
119) Which place is located on water divide of river Ganga and the Indus?
Answer: Plains of Ambala.
120) From where does river Brahmaputra originate?
Answer: The Brahmaputra rises in Tibet, east of Mansarovar lake very close to the sources of the Indus and the Satluj.
121) From where does river Brahmaputra enter India?
Answer:On reaching the Namcha Barwa, Brahmaputra takes a 'U' turn and enters India in Arunachal Pradesh through a deep gorge.
122) Which tributaries join Brahmaputra in Assam?
Answer: It is joined by the Dibang, Lohit, Kenula to become Brahmaputra.
123) By what name is Brahmaputra known in Tibet and Bangladesh?
Answer: In Tibet it is known as Tsang-Po and in Bangladesh it is called Jamuna.
124) Why does river Brahmaputra carry less water in Tibet?
Answer: In Tibet, the river carries a smaller volume of water & less silt as it is a cold and a dry area.
125) How does Brahmaputra river cause damage in Assam during rainy season?
Answer: Every year during the rainy season, the river overflows its banks, causing widespread devastation due to floods in Assam.
126) Name the major Peninsular rivers.
Answer:The Mahanadi, the Godavari, the Krishna and the Kaveri.
127) Which two peninsular rivers form-estuaries?
Answer: Narmada and Tapi.
128) Which Peninsular rivers form delta?
Answer:The Mahanadi, the Godavari, the Krishna & the kaveri.
129) At what place Narmada river rises?
Answer:The Narmada rises in Amarkantak hills in Madhya Pradesh.
130) How does river Narmada create picturesque locations?
Answer:The 'Marble Rocks' near Jabalpur where Narmada flows through a deep gorge and the 'Dhuadhar falls' where the river plunges over steep rocks are some of the example.
131) From which states Narmada river Hows?
Answer:River Narmada flows in Madhya Pradesh and Gujarat.
132) From where does River Tapi originate?
Answer:The Tapi rises in the Satpura range in Betui district of Madhya Pradesh.
133) Which are the main west flowing rivers of Western Ghats?
Answer:Sabarmati, Mahi, Bharathpuzha and Periyar.
134) Which river is the largest Peninsular river?
Answer: The Godavari, it's length is about 1500 km.
135) The Godavari rises from which place?
Answer:The Godavari rises from the slopes of Western Ghats in the Nasik district of Maharashtra.
136) In which states Godavari's basin lies?
Answer:Maharashtra, Madhya Pradesh, Odisha and Andhra Pradesh.
137) Name the tributaries of river Godavari.
Answer:The Purna, the Wardha, the Pranhita, the Manjra, the Wainganga and the Penganga.
138) Which river is called 'Dakshin Ganga'?
Answer:Godavari is called 'Dakshin Ganga' because of its length and the area it covers.
139) From where the Mahanadi river rises?
Answer: The Mahanadi rises in the highlands ofChhattisgarh.
140) What is length of river Mahanadi?
Answer: It is about 860 km.
141) From which states river Mahanadi passes?
Answer: River Mahanadi passes from Maharashtra, Chhattisgarh, Jharkhand and Odisha.
142) From which region River Krishna rises?
Answer:River Krishna rises from a spring near Mahabaleshwar.
143) What is the length of river Krishna?
Answer: The Total length of river Krishna is about 1400 km.
144) Name the major tributaries of River Krishna.
Answer:The Tungabhadra, the Koyana, the Ghatprabha, the Must and the Bhima.
145) In which states the basin of river Krishna lies?
Answer: The basin of river Krishna is shared by Maharashtra, Karnataka and Andhra Pradesh.
146) From which place river Kaveri originates and at which place it merges?
Answer:The Kaveri rises in Brahmagri range of the Western Ghats and it reaches the Bay of Bengal in South of Cuddalore in Tamil Nadu.
147) What is the total length of river Kaveri?
Answer:The Total length of river Kaveri is about 760 km.
148) Name the tributaries of river Kaveri?
Answer:Its main tributaries are Amravati, Bhavani, Hemavati and Kabini.
149) Which regions of India are drained by river Kaveri?
Answer:Its basin drains parts of Karnataka, Kerala and Tamil Nadu.
150) What is 'Shivasamudram'? What is its use?
Answer:The river Kaveri makes the second biggest waterfall in India. It is known as Shivasamudram. The hydroelectric power generated from the falls is supplied to Mysore, Bangalore and the Kolar Gold Field.
151) How are lakes formed?
Answer:There are some lakes which are the result of the action of glaciers and ice sheets, while the others have been formed by wind, river action and human activities.
152) How ox-bow lakes are formed?
Answer:A meandering river across a flood plain forms cut-offs that later develop into ox-bow lakes.
153) How lagoons are formed?
Answer: Lagoons are salt water lakes which are formed with spits and bars in the coastal areas, for example, the Chilka Lake.
154) How lakes become seasonal?
Answer:Lakes in the region of inland drainage are sometimes seasonal. For example, Sambhar lake of Rajasthan.
155) What are fresh water lakes?
Answer: Fresh water lakes are mostly found in the Himalayan region. They are formed when glacier dug out a basin, which was later filled with snowmelt water.
156) Name some of the fresh water lakes of India.
Answer: The Wular lake. The Dal lake, Bhimtal, Nainital, Loktak and Barapani.
157) How man-made lakes are formed?
Answer: The drainage of rivers for the generation of hydroelectric power also led to the formation of lakes called man-made lakes. For example. Guru Gobind Sagar Lake (Bhakra Nangal Project).
158) What is the importance of lakes?
Answer:Lakes moderate the climate of surroundings, maintain the aquatic ecosystem, enhance natural beauty, help develop tourism and provide recreation.
159) How rivers help in an agricultural country like India?
Answer:Rivers help in irrigation, navigation, hydro-power generation to help the farmers in their production and marketing.
160) How growing demand of water from rivers, affects the quality of water?
Answer:More and more water is drained out of the rivers for growing domestic, municipal, industrial and agricultural demands of water, which reduces their volume. On the other hand, a heavy load of untreated sewage & industrial effluents are emptied into the rivers, affecting the quality of water.
161) What does 'drainage' mean? What is a 'drainage basin'?
Answer: (i) The term 'drainage' means the river system of an area.
(ii) Some small streams flowing from different directions come together to form the main river, which ultimately drains into a large water body. The area drained by a single river system is called a 'drainage basin'.
162) What is meant by 'water divide'? Give an example.
Answer:(i) Any elevated area such as a mountain or a plateau that separates two drainage basins is known as a 'water divide'. (ii) For example, Ambala is located at the water divide between the Indus and Ganga rivers. It does not receive water from either of the two rivers.
163) From where does the river Indus originate and which tributaries join the main river?
Answer: (i) Several tributaries such as the Zaskar, Nubra, Shyok and the Hunzajoin the river Indus in Kashmir.
(ii) The Satluj, Beas, Ravi, Chenab andJhelum rivers join together to enter the Indus near Mithankot in Pakistan.
164) From where does the river Ganga originate and which tributaries join it?
Answer:The river Ganga originates from the Gangotri glacier as 'Bhagirathi'. Then it is joined by Alaknanda at Devaprayag in Uttarakhand. The Ganga is joined by many rivers from the Himalayas such as Yamuna, Ghaghara, Gandak and the Kosi rivers. The river Yamuna originates from the Yamunotri glacier, but joins the river Ganga at Allahabad. The main tributaries which come from the peninsular uplands are the Chambal, the Betwa and the Son.
165) Prepare a short note on the 'Sunderban Delta'.
Answer:The Sunderban Delta is the world's largest and the fastest growing delta. Filled by various tributaries, the river Ganga reaches West Bengal. This is the northernmost part of the Ganga Delta. From here, the Bhagirathi-Hooghly (a distributary) flows southwards towards the deltaic plains and the Bay of Bengal. The main stream flows southwards into Bangladesh and is joined by Brahmaputra, known as Meghna. This mighty river (with waters from Ganga and Brahmaputra) forms the deltaic plains and then flows into the Bay of Bengal. It derives its name from the Sundari tree which grows in marshland.
166) How does the Brahmaputra river enter India? Which are its tributaries?
Answer: (i) The Brahmaputra rises in Tibet, near the Mansarovar lake. Then it flows eastwards, parallel to the Himalayas. On reaching the Namcha Barwa, it takes a U-turn and enters India into Arunachal Pradesh through a deep gorge. (ii) Its tributaries are - the Dibang, Lohit and Kenula.
167) From where does the river Narmada originate? How is the Narmada basin formed?
Answer:The Narmada river rises in the Amarkantak hills in Madhya Pradesh. From here, it flows towards the west in a rift valley. In Jabalpur, it passes through a deep gorge of'marble rocks'. It also forms the 'Dhuadhar falls'. It passes through the states of Madhya Pradesh and Gujarat.
168) Prepare a short note on the river Tapti.
Answer:(i) The Tapti rises in the Satpura ranges in Betui district of Madhya Pradesh.
(ii) It also flows in a rift valley parallel to the Narmada river.
(iii) Its basin covers parts of Madhya Pradesh, Gujarat and Maharashtra.
169) Give a brief description of 'Dakshin Ganga'.
Answer: (i) The Godavari river is the largest Peninsular river.
(ii) It rises from the slopes of the Western Ghats in the Nasik district of Maharashtra.
(iii) Its length is 1,500 km and it drains into the Bay of Bengal.
(iv) Its drainage basin is also the largest among the peninsular rivers.
(v) Its tributaries are?the Puma, Wardha, Pranhita, Manjra, Wainganga and the Penganga. (vi) This basin covers parts of Maharashtra, MP, Odisha and Andhra Pradesh.
170) What do you know about the Mahanadi river?
Answer: (i) The Mahanadi rises in the highlands of Chhattisgarh.
(ii) It flows through Odisha to reach the Bay of Bengal.
(iii) The length of the river is about 860 km.
(iv) Its drainage basin is shared by the states of Maharashtra, Chhattisgarh, Jharkhand and Odisha.