Drainage-chapter -3-Geography 9class
Define the following terms: Drainage, Drainage basin, Water divide, River system.
Ans1.Drainage is the river system of an area.
Drainage Basin:-drainage basin is the area which the river is draining. It is basically the path of a river.
Water Divide:-The point where a river divides and form its distributaries is known as the water divide. Eg: western Ghats in Peninsular India & Ambala.
River System:-A river along with its tributaries is called the river system.
Q2. Name two groups into which Indian rivers are divided?
Ans2.The Himalayan rivers and the peninsular rivers.
Q3. What are perennial and seasonal rivers? give examples.
Ans3.Perennial rivers are the rivers which receive water throughout the year eg. the Himalayan rivers like river Ganga, Indus & Brahmaputra.
seasonal rivers are the rivers which receive water in the monsoon season eg. all peninsular rivers like river Godavari, Krishna, Kaveri, Mahanadi etc.
Q4. Write about different Drainage patterns formed by rivers.
.
Ans4.Different drainage patterns formed by rivers are:-
Dendritic Pattern- It is the branch like pattern formed by the rivers. It is generally formed where the river channels follows the slope of the terrain.
Trellis pattern-When a river is joined by its tributaries on approximately right angles forms trellis pattern. It forms where hard & soft rocks exists parallel to each other.
Rectangular Pattern-When a river by joining with its tributaries forms the shape of a rectangle it forms the rectangular pattern.It develops on strongly joined rocky areas.
Radial pattern-when some rivers flows in different directions from a central peak it forms radial pattern.
Ans- The river Indus is one of the longest river of the world.
-- The Indus plain has a very gentle slope with a total length of 2900km.
--The river rises in Tibet near mansarovar lake.
--It enters India in the Ladakh district of Jammu and Kashmir. It forms a picturesque gorge in this part.
--The Satluj, The Beas, The Ravi, The Chenab and The Jhelam join together to enter Indus near Mithankot in Pakisatan. The Indus flows through Baltistan and Gilgit and emerges from the mountains at Attock.
Indus - water Teaty
--According to the Indus water treaty in 1960, India can use only 20% of the total water carried by Indus river system. This water is used for irrigation in Punjab, Harayana and southern and western parts of Rajasthan.
Q6. Write about Ganga river system.
ANS.River Ganga:
The length of river Ganga is over 2500 km.
1.The headwaters of river Ganga are called “Bhagirathi” and is joined by the river Alaknanada at Devprayag in Uttaranchal
2.. Ganga is fed by Gangotri glacier
3. At Haridwar Ganga emerges on the plains from the mountains.
4.The Ganga is joined by many tributaries from Himalayas, some of them being Yamuna, Ghaghara, Gandak and Kosi.
The tributaries coming from Peninsular uplands are the Chambal, the Betwa and the Son.
5. The Ganga flows eastwards till Farakka in West Bengal. this is northern most point of ganga delta. the river bifurcates here: Bhagirathi- Hoogly.
6.Ganga flows southwards through the deltaic plains to the Bay of Bengal.
--the mainstream, flows southwards into Bangladesh and is joined by the Brahmaputra. further down stream, it is known as the Meghna. this mighty river,with waters from the Ganga,and the Brahmaputra,flows into Bay of Bengal. the delta formed is called Sunderban delta.
The Brahmputra river.
SOURCE OF RIVER:the brahmputra rises in Tibet east of Mansarowar lake very close to the sources of the Indus and Satluj.
MOUTH OF RIVER: it joins Ganga river in Bangladesh and form a delta called sunderban'........it flows down in Bay of Bengal
DRAINAGE AREA: it flows eastwards to parallel to the Himalayas. on reaching the Namcha Barwa[7757m],it takes a u' turn and enters india in Arunachal Pradesh through a gorge .here it is called the Dihang and it is joined by the Dibang, the Lohit and many other tributaries to form the Brahmputra in Assam.
SPECIAL FEATURE:in Tibet the river carries a smaller volume of water and less silt as it is a cold and a dry area. in India it passes through a region of high rainfall.the Brahmaputra has a braided channel .in it entire length in Assam and forms many riverrine islands.
Q7. Write about river systems of Narmada and Tapi
Ans1: THE NARMADA
a) Narmada river rises in the Amarkantak hills in Madhya Pradesh.
b) It flows into the Arabian sea in the west.
c) It's basin covers parts of Madhya Pradesh and Gujarat.
d) The Narmada creates many beautiful& picturesque locations.
e) All tributaries of the Narmada are very short and most of these join the main stream at right angles.
THE TAPI
a) Tapi rises in the Satpura ranges, in the Betul district of Madhya Pradesh.
b) It flows into the Arabian sea.
c) Its basin covers parts of MP, Gujarat, Maharashtra.
d) The coastal plains between western ghats & Arabian sea are very narrow, hence, this river is very short.
Q8.Distinguish between the Himalayan and Peninsular river systems
Ans2: THE HIMALAYAN RIVERS
a) Major Himalayan rivers are- the Indus, the Ganga, the Brahmaputra.
b) Himalayan rivers gives water throughout the year./ these are perenninal rivers.
c) Ganga is the longest river in Himalayan rivers.
d) These rivers are long and are joined by many large tributaries.
e) E xcept river Indus, other two fall in the Bay of Bengal.
THE PENINSULAR RIVERS
a) Major peninsular rivers are- the Mahanadi, the Krishna, the Kaveri, the Godavari in the east & the Narmada and the Tapi on west.
b) Peninsular rivers give water only in rainy season./ these rivers are seasonal.
c) Godavari is the largest river in peninsular rivers.
d) These rivers are comparatively smaller in size.
e) Except Narmada and Tapi all other rivers drain into Bay of Bengal.
Q9.River Godaveri: a note]
Ans1.The Godavari is the largest peninsular river.
--It rises from the slopes of the western ghats in Nasik, Maharashtra.
--It is about 1500km long and drains into the Bay of Bengal.
--Its basin covers parts of Maharashtra, Madhya Pradesh, Orissa and Andhra Pradesh.
--Godavari is joined by tributaries such as the Purna, the Wardha, the Pranhita,the Manjra, the Wainganga and the Penganga.
--It is also known as the 'Dakshin Ganga', because it is the largest river in the peninsular region.
Mahanadi:
--The Mahanadi rises in the highlands of Chattisgarh.
--It flows through Orissa and reaches Bay of Bengal.
--It is about 860 km in length.
--Its drainage basin is shared by Maharashtra, Chhattisgarh, Jharkhand and Orissa.
Q.write about river systems of krishna and kaveri.
Ans.THE KRISHNA BASIN
1.Krishna river rises from a spring near Mahabaleshwar.
2.It flows for about 1400km and reaches the Bay of3.Bengal.
3.The Tungabhadra,the Koyana,the Ghatprabha,the
Musi and the Bhima are some of its tributaries.
4.Its drainage basin is shared by Maharasthra Karnataka and Andhra Pradesh.
THE KAVERI BASIN
1.The Kaveri river rises in the Brahmagri range of the Western
ghats and reaches the Bay of Bengal in south of Tamil Nadu.
2.The total length of river is 760km.
3.Its main tributaries are Amravati,Bhavani,Hemavati and Kabini.
4.Itsdrainage basin includes the parts of Karnataka,Kerala and
Tamil Nadu.
5.It has several water falls in its course of theseSivasamundram deserves mention.
6.The Damoder,the Brahmani, the Baitarni and the Subarnrekha are some small rivers flowingtowards the East
Q10. India has many lakes, mention their names and also wirte about fresh water and salt water lakes.
LAKES-Lakes differ from each other in the size, and other characterstics.
Most lakes are permanent; but some contain water only during the rainy season,
like the lakes in the basins of inland drainage of semi-arid regions. there are some of the 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.
Examples of some lakes- Dal lake,Chilika lake,Sambhar lake,Wular lake,Nainital etc.
Q11. Write about the importance of lakes to human beings.
Importance-.Lakes are of great value to human beings.
1. A lake helps to regulate the flow of a river.
2.During heavy rainfall, it prervents flooding and during the dry season,I t helps to maintain an even flow of water.
3.Lakes can also be used for developing hydel power.
4.They moderate the climate of the surroundings and maintain the aquatic eco system.
5. Enhance natural beauty, help develop tourism and provide recreation.
Q12- Write a short note on River Pollution.
Ans- The growing domestic, municipal, industrial and agricultural demand for water from rivers naturally affects the Quality of water. As a result, more and more water is being drained out of the rivers reducing their volume.
--This affects not only the quality of water but also self-cleansing capacity of the river.
--The increasing urbanisation and industrialisation do not allow it to happen and the pollution level of many rivers has been rising.
-- Concern over rising pollution in our rivers lead to the launching of various action plans to clean the rivers as Ganga Action Plan, Cleaning of river Yamuna etc.
OR
Q13. What are the causes of river water pollution?
Ans.Causes of water pollution:
1.A heavy load of untreated sewage and industrial effluents are emptied into the rivers.
2.The increasing urbanisation and industrialisation do not allow self-cleansing of rivers to happen and the pollution level of many rivers has been rising.
No comments:
Post a Comment