CHAPTER-1

ON THE ROOF OF THE WORLD

1) Which mountain range is known as the Roof of the World"?

📚 Pamir Knot

2) Write short note about The Northern Mountain Region?

📚 Landforms with an average elevation above 900 metres from the sea level. 

■ Formed by the folding of rock layers. 

📚 Extends from River Indus in the west to River Brahmaputhra in the east. 

■ Presence of high peaks,glaciers and valleys.

3) Based on the topographical characteristics, the Northem mountain region can be classified into three. Which are they?

🟢 Trans Himalayas

🟢The Himalayas

🟢The Eastern Hills

4) How Fold mountains are formed? Write examples. 

■ Formed due to the compression of sedimentary rock strata of the earth's crust.

■ The Himalaya, The Alps

5) Point out the features of Trans Himalaya?

■ Known as the Tibetan Himalayas.

■ Average elevation of 3000 metres. 

■ Approximate width of 40 km and a length of 965 km.

6). Himalayas are divided into three .What are they?

📚 HIMALAYAS

a) Himadri

▫️Greater Himalayas. 

▫️Average elevation 6100 meters. 

▫️width nearly 25km. 

▫️snow clad mountain. 

b) Himachal

▫️ Lesser Himalayas

▫️Elevation 3500-4500metres. 

▫️width ranging from 60 to 80km. 

c) Shiwalik 

▫️Outer Himalayas, Inner Himalayas

▫️Southern most range borders of the Ganga plains. 

▫️width ranging from 60 to 150km. 

7). What are lithospheric plates?

■ Portions of lithospheric parts, each with thousands of kilometres of width and nearly 100 km thickness are known as a lithospheric plates.

■ It includes the crust and the upper mantle.

■ These plates may cover the continental portion, ocean bottom or both. 

8). There are three types of plate boundaries. Which are they?write its features?

■ Convergent Boundary: Boundaries where plates move towards each other.

■ Divergent Boundary: Boundaries where plates move away from each other.

■ Transform(Shear) Boundary: Boundaries where plates slide part each other. 

9). How the Himalayas were formed?

📚 The Indian Plate which moved northwards and came close to the Eurasian Plate. 

📚 The Tethys (ocean) seabed situated between the two landmasses, started uplifting and the Himalayas were formed.

10) Write the regional divisions of the Himalayas?

a) Western Himalayas 

b) Central Himalayas

c) Eastern Himalayas

11). Write short note about the Western Himalayas?

■ Stretches from the Indus river valley to the north of Jammu and Kashmir upto the Kali river valley. 

◻️Classified into three: 

👉Kashmir Himalaya,

👉 Himachal Himalaya, 

👉Uttarakhand Himalaya.

🟢 KASHMIR HIMALAYA 

12) Point out the important mountain ranges of Kashmir Himalaya?

◽ Karakoram, 

◽Zaskar, 

◻️Ladakh 

◻️Pir Panjal.

13). Name the second highest peak in the world, which is situated in the Karakoram range?

■ Mount K2 (Godwin Austin - 8611 metres)

14) Find out the important glaciers of the Kashmir Himalaya?

📚 Siachen, 

📚 Boltoro

15) What are Passes?

 Write an example?

■ Passes are the comparatively easier natural passages in the mountainous terrains.

■ Banihal Pass (across the Pir- Panjal Range that connects Jammu with the Kashmir Valley) 

16) Why are the Himalayan rivers an rivers water-rich year-round?

📚 They are perennial rivers. 

📚 They are either fed by the glaciers from the mountains or by the heavy rainfall.

17) Name the important fresh water lakes in the Kashmir Himalaya?

 👉 Dal Lake ( Srinagar) 

18) What are 'Margs"? Write examples?

■ 'Margs' are meadows formed along the mountain slopes during the summer season. 

👉 Sonmarg and Gulmarg

19). Write short note about Kashmir tourism?

■ Srinagar situated on the banks Dal Lake an important tourist and commercial centre.

◻️The Shikara boats and floating markets are the hallmarks of Kashmir tourism.

🟢 HIMACHAL HIMALAYAS 

20). Name the important rivers in Himachal Himalaya region?

Chinab, Ravi and Beas

21). Name the mountain ranges in Himachal Himalaya region?

■ Dhowladhar and Pir Panjal

22). Name the freshwater lakes found in himachal Himalaya ?

📚 Chandratal and Surajtal

23) . Which are the important passes in Himachal Himalaya?

a) The Baralacha La Pass that connects Himachal Pradesh with Ladakh. 

b) Rohtang Pass that connects Kulu Valley with Lahul and Spiti Valleys. 

24) . List out the tourist centers of Himachal Himalaya?

📚 Beautiful valleys such as Kulu, Kangra and Lahul.

📚 Tourist centres such as Shimla and Manali

25). Name the peaks which are situated in the Uttarakhand Himalaya?

■ Nandadevi, Kamet, Badrinath, Kedarnath

26). Name the glaciers and freshwater lakes situated in Uttarakhand Himalaya?

■ The Gangotri and Yamunotri glaciers

◻️Freshwater lakes - Nainital and Bhimtal. 

27) What are dunes? Write an example?

📚. The flat valleys seen in between the Lesser Himalayas and the Shiwalik hill ranges are Duns. 

■ Eg: Dehradun in Uttarakhand. 

28). Why the Central Himalayas is also known as the Nepal Himalaya?

📚 Since the majority of this region falls in Nepal.

29 ). Which is the world's highest peak?

📚 Mount Everest(Nepal)

 

30). Which Himalayan region is also known as Assam Himalayas? 

■ Eastern Himalayas

31). Which is the highest peak in Eastern Himalayas region? 

■ Namcha Barwa (7756 m)

32). Which are the important rivers in the Eastern Himalayas region?

📚 Brahmaputra, Kameng, Lohta and Subansiri

33). Name the important passes in the Eastern Himalayas region?

■ Bomdila Pass which connects Arunachal Pradesh with Lhasa( the capital city of Tibet)

◻️ Diphu pass which connects Arunachal Pradesh with Myanmar. 

34). Write short note on Purvachal Region?

📚 The Himalaya mountains hills having an average elevation from 500 to 3000 metres above mean sea level are known as Purvachal Hills.

👉 Of these the most important are the Patkaibum, the Naga Hills, the Mizo Hills and the Manipur Hills.

👉 Cherrapunjii and Mawsynram located here receive the highest rainfall in the world.

 35). What are the different factors that affect the climate of the Himalayan mountain zone? 

Write the features of Himalayan climates?

📚 The elevation and the topography of the respective parts of the region.

📚 Mild climate prevails along the lower mountain slopes and the Shiwalik foothills.

📚 At higher elevations, it will be considerably low temperature. 

📚 Winter climate conditions at extremely high altitudes and in the Ladakh region. 

📚 Pole-like extreme winter climate is experienced.

📚 South West Monsoon rains are received along the southern slopes of the Shiwalik ranges and the North Eastern India.

📚 Snowfall is common in the higher regions of the mountains.

📚 The North Eastern India, especially the Meghalaya Plateau, receives heavy rainfall.

👉 Name the Himalayan Rivers?

Indus, Ganga, and Brahmaputra rivers. 

👉 The Himalayan rivers are flood prone even during summer. Why?

■ As these rivers are rainfed and snowfed, they are perennial (water rich) throughout the year. 

35) Name the land forms created by Himalayan rivers?

V-shaped valleys, gorges and waterfalls

 36). Write brief note about soil types of Himalayas?

📚 Mountain soil and forest soil are commonly seen in the Himalayan terrain. 

📚 The soil texture and particle size vary according to mountain environment.

📚 Fine grained soil with high humus content are seen in the valleys

In the high slopes, coarse grained soil with low humus content can be seen.

📚 Alluvial deposition is mainly seen in the valleys.

37). Name the glacial sediment deposited in the Kashmir Valley?

📚 Karewas

(soil is ideal for saffron cultivation) 

38). What are the different factors which lead to regional variations in natural vegetation in the Himalayan terrain?

1)Elevation, 

2)Topography , 

3)Soil type and climate

39). Write short note on natural vegetation in the Himalayan terrain?

👉 Tropical evergreen vegetation is found in the Eastern Himalayas and the North Eastern Hills.

👉 Vegetation type of the cold climates such as Tundra.

👉 Semi-evergreen and deciduous forests are seen in the valleys and the lower mountain slopes.

👉 Coniferous tree varieties such as pine and deodar grow more along the mountain slopes.

👉 Shrubs such as junipers and rhododendrons grow at higher altitudes. 

👉 In the highest altitude, alpine meadows are seen. 

41). Name the common wild animals in the Himalayan region?

📚 yak, musk deer, single- horned rhinoceros and snow leopard.

42) . How wildlife are protected in the Himalayan terrain?

📚 Established Biosphere Reserves, National Parks and Wildlife sanctuaries. 

43). Which are the adverse factors that help in the growth of agricultur in the Himalayan region?

📚 Elevation, 

📚Steepness of slope,

 📚immature soil, 

📚low temperature

44). What are the different crops cultivating in the Himalayan region?

👉 Crops like paddy, legumes and potatoes during the rainy season. 

👉 Wheat, and temperate fruit crops during the spring.

👉 Tea is a major crop along mountain slopes and valleys of Eastern Himalayas. 

45). Name the shepherd tribes who live in the mountain meadows of Western Himalayas?

■ Gujjars

46). Write short note on Tourism in the Himalayan region?

◻️The entire Himalayan region has high economic potential for tourism.

◻️Travels associated with pilgrimage were what 

initiated the development of tourism in these regions. 

◻️There are several pilgrim centres in this region such as Kailas, Manasarovar, Amarnath and Hema Kund Sahib.

◻️The resort towns such as Shimla, Darjeeling, Shillong, Almora, Ranikhet, Mussoorie and Nainital

are important tourist centres because of favourable climate. 

◻️Today the adventure tourism sector promoting Mountaineering, Paragliding, skiing etc. has developed significantly in this region.

 Chapter - 4

BY THE HANDS OF THE NATURE

1. What are the various landf

orms on earth.

◻️The mountains, valleys, plains, plateaus, waterfalls, etc.

2. What are geomorphic processes?

◻️The processes that help in the formation of landforms are called geomorphic processes. 

3. What are geomorphic agents? Write examples.

◻️Varied landforms are created by the continuous processes carried out by external agencies these agencies are often called geomorphic agents.

👉 Running water, wind, glaciers, sea waves, etc.

4. What is the difference between erosion and deposition?

👍🏻 The transfer of rock particles from one place to another by external agencies such as running water, wind, glaciers, sea waves, etc. is called erosion. 

👍🏻 The materials carried by external agencies will be deposited in low lying regions and this process is called deposition. 

5. Name the factors that determine the flow of a river.

◻️Volume of water,

◻️ Rock structure,

◻️ Slope of the terrain, 

◻️Amount of sediments

[10/12, 11:02 pm] Athul Kamukumchery: 6. How V-shaped valleys are formed?

The valleys take a distinct shape as a result of the intensity of erosion along the river bed. Such valleys are called V-shaped valleys.

7. How Waterfalls are formed?

◻️Waterfalls are generally formed at the upper course of rivers as a result of erosion.

◻️Soft rocks are easily eroded in the valleys where soft and hard rocks are found intermingled. This results in the formation of waterfalls.

8. What are meanders?

📚 The sinuous curves formed along the river course are called meanders.

9. How oxbow lakes are formed?

📚 Meanders may further curve through continuous erosion and deposition. Finally the river takes a straight course. 

Due to deposition the curves may get detached from the main river form isolated water bodies. Such water bodies are called oxbow lakes. 

10. What are flood plains?

 Write the importance of flood plains. 

The deposition of alluvium along both the flooded banks may cause the formation of plains.

 Such plains are called flood plains.

[10/12, 11:03 pm] Athul Kamukumchery: 11. Write the features of Karst topography?

Rocks like limestone easily dissolve in rainwater which percolates to form underground water.

The erosional and depositional landforms of underground water are mainly confined to limestone regions. Such landform features are generally called Karst topography.

12. Write short note about landforms created by underground water.

◻️ Limestone caves- Caves formed by the solution of limestone in underground water.

◻️Stalactites-The deposit of lime grows upside down due to long continued depositional process in limestone caves. These are called Stalactites

◻️ Stalagmites :The deposit of lime on the floor of the cave also grows upward as a result of the deposition from above. These are called stalagmites.

◻️ Limestone pillars : Stalactites and stalagmites do merge together with to form pillars.

13. Coastal landforms are created by the erosional and depositional processes carried out by waves. Which are they? How they are formed?

 1)Sea cliffs-The steep hillocks facing the sea are called sea cliffs.

They are formed by the crumbling of the sea-facing slopes due to wave erosion Eg:Varkala beach in Thiruvananthapuram district.

 2)Stacks- Pillar like rocks standing upright along the coastline are called stacks.

The strong blast of sea waves on the rocky coasts causes the wearing down of rocks. As a result of such abrasion by waves, isolated rock pillars are formed from coastal rocks.

 Eg: Stacks found along the coast of Thalassery in Kannur district.

3) Beaches -They are depositional landforms along the coastlines formed with sand, gravel etc.

 Eg: Kovalam, Cherai

[10/12, 11:12 pm] Athul Kamukumchery: 14. What is a glacier?

◻️Slow moving mass of ice is called a glacier.

15. What are cirques?

Arm chair like valleys formed by glacial erosion are called cirques.

16. How U-shaped valleys are formed?

The erosion caused by the continuous movement of glaciers along the valleys carves out steep sided and flat bottomed U-shaped valleys.

17. Name the depositional landform created by glaciers? 

How it will be formed?

📚 Moraines

The sediments carried down by the glaciers will be deposited in various parts of the valley.

 These depositional features by glaciers are called moraines

18. What is the difference between degradation and aggradation?

◻️The elevated regions are levelled down by erosion and low lying regions are filled by deposition. These processes are called degradation and aggradation respectively.

• The processes together are generally called gradation

19. List out the human activities that bring changes to the earth's surface.

◻️Reclamation of agricultural fields.

◻️Deforestation

◻️Mining

ഭൂമിയുടെ പുതപ്പ്

UNIT: 10

      *ഭൂമിയുടെ പുതപ്പ്*

1. എന്താണ് അന്തരീക്ഷം? 

◻️ഭൂമിയെ ആവരണം ചെയ്തിരിക്കുന്ന വായുവിന്റെ പുതപ്പാണ് അന്തരീക്ഷം. 

2.ഓക്സിജൻ,കാർബൺഡയോക്സൈഡ് എന്നീ വാതകങ്ങളുടെ അളവിനെ നിയന്ത്രിക്കുന്നതിൽ സസ്യങ്ങൾക്കുള്ള പങ്കെന്ത്?

◻️സസ്യങ്ങൾ അവയുടെ വളർച്ചയ്ക്കാവശ്യമായ ഊർജം സംഭരിക്കുന്നത് പ്രകാശസംശ്ലേഷണത്തിലൂടെയാണ്.

◻️ഇതിലൂടെ സസ്യങ്ങൾ കാർബൺഡയോക്സൈഡ് ആഗിരണം ചെയ്യുകയും അന്തരീക്ഷത്തിലേക്ക് ഓക്സിജൻ പുറന്തള്ളുകയും ചെയ്യുന്നു.

◻️മനുഷ്യനും മറ്റു ജീവജാലങ്ങൾക്കും ആവശ്യമായ പ്രാണവായുവാണ് ഈ ഓക്സിജൻ. 

3. ജീവജാലങ്ങളുടെ നിലനിൽപ്പിന് നൈട്രജൻ, കാർബൺ ഡയോക്സൈഡ് ഓക്സിജൻ, എന്നീ വാതകങ്ങൾക്ക് എത്രമാത്രം പ്രാധാന്യമുണ്ടെന്ന് കണ്ടെത്തുക.

◻️പ്രകാശസംശ്ലേഷണത്തിന് സസ്യങ്ങൾ കാർബൺ ഡയോക്സൈഡ് ഉപയോഗപ്പെടുത്തുന്നു. 

◻️ ശ്വസനപ്രക്രിയയ്ക്കായി മനുഷ്യനും മറ്റു ജന്തുജാലങ്ങളും ഓക്സിജൻ ഉപയോഗപ്പെടുത്തുന്നു. 

◻️ നൈട്രജൻ സ്ഥിതീകരണത്തിലൂടെ സസ്യവളർച്ചയ്ക്കായി നൈട്രജൻ ഉപയോഗപ്പെടുത്തുന്നു.

4. ഏതൊക്കെ മാർഗങ്ങളിലൂടെയാണ് മുഖ്യമായും പൊടിപടലങ്ങൾ അന്തരീക്ഷത്തിലെത്തിച്ചേരുന്നത്? 

• കാറ്റിലൂടെ ഭൂമിയിൽനിന്ന് ഉയർത്തപ്പെടുന്നവ.

• അഗ്നിപർവതങ്ങളിലൂടെ പുറത്തുവരുന്നവ.

◻️ ഉൽക്കകൾ കത്തുന്നതിലൂടെ ഉണ്ടാകുന്ന ചാരം. 

5. അന്തരീക്ഷത്തിലെ നേർത്ത പൊടിപടലങ്ങളെ ഘനീകരണമർമം എന്ന് വിശേഷിപ്പിക്കാൻ കാരണമെന്ത്?

👉 മേഘരൂപീകരണത്തെ സഹായിക്കുന്നതിനാൽ. 

6. അന്തരീക്ഷത്തിലെ പൊടിപടലങ്ങൾക്കുള്ള പ്രാധാന്യമെന്ത്?

* അന്തരീക്ഷത്തിലെ നേർത്ത പൊടിപടലങ്ങളെ കേന്ദ്രീകരിച്ച് ഘനീകരണ പ്രക്രിയ നടക്കുന്നതു കൊണ്ടാണ് മേഘങ്ങൾ രൂപപ്പെടുന്നത്.

7.  എവറസ്റ്റ് കൊടുമുടി കയറുന്ന പർവ്വതാരോഹകർ ഓക്സിജൻ സിലിണ്ടർ ഒപ്പം

കരുതുന്നതെന്തിനാണ്?

◻️ഉയരം കൂടുന്തോറും വാതകങ്ങളുടെ (ഓക്സിജൻ) അളവ് കുറഞ്ഞു വരുന്നു.

.7. ശൈത്യമേഖലാ രാജ്യങ്ങളിൽ കെട്ടിടങ്ങൾ നിർമിക്കുമ്പോൾ സ്ഫടികം കൂടുതലായി ഉപയോഗിക്കാറുണ്ട്. എന്തുകൊണ്ട്?

◻️സ്ഫടികതലങ്ങൾക്ക് സൗരോർജത്തെ (സൗരതാപനത്തെ) ഉള്ളിലേക്കു കടത്തി വിടാനും ഭൗമവികിരണത്തെ തടഞ്ഞു നിർത്താനും കഴിവുണ്ട്.

◻️ഇത്തരത്തിൽ കെട്ടിടങ്ങൾക്കുള്ളിൽ താപം കുറയാതെ നിലനിർത്താനാകുന്നു. 

8. താഴെ പറയുന്ന പദങ്ങൾ എന്തെന്ന് വിശദമാക്കുക.

a) *ഹരിതഗൃഹങ്ങൾ*

ഭൗമവികിരണത്തെ തടഞ്ഞു നിർത്തി സസ്യവളർച്ചയ്ക്കാവശ്യമായ താപം ഉള്ളിൽ നിലനിർത്താൻ സ്ഫടിക നിർമ്മിതികൾകൊണ്ട് കഴിയുന്നു. അതിനാൽ ഇവയെ ഹരിതഗൃഹങ്ങൾ (Green Houses) എന്നാണു വിളിക്കുന്നത്.

b) ഹരിതഗൃഹ പ്രഭാവം,

ഹരിതഗൃഹവാതകങ്ങൾ

• കാർബൺ ഡയോക്സൈഡ്, മീഥേൻ, ഓസോൺ തുടങ്ങിയ വാതകങ്ങളും നീരാവിയും ഭൂമിയിൽ നിന്നുയരുന്ന ഭൗമവികിരണത്തെ ആഗിരണം ചെയ്ത് ഭൂമിയോടടുത്തുള്ള അന്തരീക്ഷത്തിലെ താപനില കുറയാതെ നിലനിർത്തുന്നു. 

ഈ പ്രതിഭാസത്തെ *ഹരിതഗൃഹപ്രഭാവമെന്നും* (Green House Effect) ഇതിന് കാരണമാകുന്ന വാതകങ്ങളെ *ഹരിതഗൃഹവാതകങ്ങൾ* (Green House gases) എന്നും പറയുന്നത്.

9. ഏതൊക്കെയാണ് ഹരിതഗൃഹവാതകങ്ങളുടെ സ്രോതസ്സുകൾ?

◻️അഗ്നിപർവത സ്ഫോടനം,

◻️ ജൈവവസ്തുക്കളുടെ ജീർണനം തുടങ്ങിയ സ്വാഭാവിക മാർഗങ്ങളിലൂടെയും

◻️ ധാതു ഇന്ധനങ്ങൾ കത്തിക്കൽ,

◻️ മരം മുറിക്കൽ തുടങ്ങിയ പ്രവർത്തനങ്ങളിലൂടെയും ഹരിത ഗൃഹവാതകങ്ങൾ അന്തരീക്ഷത്തിലെത്തുന്നു.

10. വർധിച്ചതോതിൽ ഹരിതഗൃഹവാതകങ്ങൾ അന്തരീക്ഷത്തിലെത്തിച്ചേരുന്നതിനു കാരണമായ പ്രവർത്തനങ്ങൾക്ക് ഉദാഹരണങ്ങൾ കണ്ടെത്തുക.

◻️വനനശീകരണം, വാഹനങ്ങളിൽ നിന്നും ഫാക്ടറികളിൽ നിന്നും പുറന്തള്ളുന്ന പുക 

11. അന്തരീക്ഷത്തിൽ കാർബൺഡയോക്സൈഡിന്റെ അളവ് കൂടുന്നതിന് വന നശീകരണം

കാരണമാകുന്നു. എങ്ങനെ?

◻️അന്തരീക്ഷത്തിലെ കാർബൺഡയോക്സൈഡ് സസ്യങ്ങൾ പ്രകാശ സംശ്ലേഷണത്തിന് ഉപയോഗപ്പെടുത്തുന്നതുകൊണ്ടാണ് അളവ് ക്രമാതീതമായി വർദ്ധിക്കാത്തത്.

◻️വനനശീകരണം മൂലം മരങ്ങൾ ഇല്ലാതാവുമ്പോൾ അന്തരീക്ഷത്തിലെ

കാർബൺഡയോക്സൈഡ് ആഗിരണം ചെയ്യാത്ത അവസ്ഥയ്ക്ക് കാരണമാകുന്നു.

12. എന്താണ് ആഗോളതാപനം?

◻️ഹരിതഗൃഹ വാതകങ്ങളിലൂടെ അന്തരീക്ഷ താപനിലയിലുണ്ടാകുന്ന വർധനവിനെ

ആഗോളതാപനം (Global Warming) എന്നു വിശേഷിപ്പിക്കുന്നു.

13. ആഗോളതാപനം ഭൂമിയിലെ ജീവജാലങ്ങളുടെ നിലനിൽപ്പിന് ഭീഷണിയാവുന്നു. എങ്ങനെ ?

 ◻️ധ്രുവപ്രദേശങ്ങളിലെ മഞ്ഞുരുകുന്നതിലൂടെ സമുദ്രജലനിരപ്പുയരും

◻️ സമുദ്രതീര ആവാസവ്യവസ്ഥയിലുണ്ടാകുന്ന നാശം ഭക്ഷ്യ ദൗർലഭ്യം, വൻതോതിലുള്ള കുടിയേറ്റം തുടങ്ങിയ പ്രശ്നങ്ങൾക്കു കാരണമാകും. 

◻️ആവാസവ്യവസ്ഥയിലെ പല സസ്യജന്തുജാലങ്ങളുടെയും നാശത്തിന് വഴിതെളിക്കും.

14. ആഗോളതാപനം നിയന്ത്രിക്കാനുതകുന്ന രണ്ട് പ്രവർത്തനങ്ങൾ എഴുതുക. 

* മരങ്ങൾ വെച്ചു പിടിപ്പിക്കുക. 

*പൊതു ഗതാഗതം കൂടുതൽ ഉപയോഗപ്പെടുത്തുക. 

15. ഓസോൺ പാളി എന്നതു കൊണ്ട് എന്താണ് അർത്ഥമാക്കുന്നത്? ഇതിന്റെ പ്രാധാന്യമെന്ത്? 

◻️അന്തരീക്ഷത്തിന്റെ ഉയർന്ന ഭാഗങ്ങളിൽ ഒരു പാളിയായി ഓസോൺ വാതകം കേന്ദ്രീകരിച്ചിരിക്കുന്നതിനാൽ ഇതിനെ ഓസോൺ പാളി എന്നു പറയുന്നു.

◻️സൂര്യനിൽ നിന്നുള്ള ഹാനികരമായ അൾട്രാവയലറ്റ് രശ്മികളെ ആഗിരണം ചെയ്യുകയും ഭൂമിയിലെ ജീവജാലങ്ങളെ സംരക്ഷിക്കുകയും ചെയ്യുന്നു.

16. ക്ലോറോഫ്ളൂറോ കാർബണുകൾ, ഹാലാൻ തുടങ്ങിയ വാതകങ്ങളുടെ സ്രോതസ്സു കൾ ഏതെല്ലാം?

റഫിജറേറ്ററുകൾ, എയർകണ്ടീഷനറുകൾ, വിവിധതരം സ്പ്രേ , അഗ്നി ശമന വാതകങ്ങൾ, പെയിന്റ് തുടങ്ങിയവ. 

17. അൾട്രാവയലറ്റ് കിരണങ്ങൾ സ്യഷ്ടിക്കുന്ന ദോഷഫലങ്ങൾ എന്തെല്ലാം?

◻️കാലാവസ്ഥാ മാറ്റം

◻️തൊലിപ്പുറത്തുണ്ടാകുന്ന കാൻസർ

◻️അന്ധത, നിശാതിമിരം

അകാല വാർധക്യം. 

◻️ആഹാരശൃംഖലയുടെ തകർച്ച

◻️ കൃഷി നാശം

◻️ സസ്യവളർച്ച മുരടിക്കൽ

18. എന്താണ് ഓസോൺ സുഷിരം? ഇത് ഉണ്ടാകുന്നതെങ്ങനെ?

◻️അന്തരീക്ഷത്തിലെ ഓസോൺ പാളിയിലുണ്ടാകുന്ന ശോഷണത്തെ ഓസോൺ സുഷിരം (ozone hole) എന്നുവിളിക്കുന്നു.

. ക്ലോറോഫ്ളൂറോ കാർബണുകൾ, ഹാലാൻ തുടങ്ങിയ വാതകങ്ങൾക്ക് ദീർഘകാലം അന്തരീക്ഷത്തിൽ മാറ്റമില്ലാതെ നിലനിൽക്കാൻ ശേഷിയുണ്ട്.

ഉയർന്ന വിതാനങ്ങളിലേക്ക് എത്തുന്ന ഈ വാതകങ്ങൾ സൂര്യനിൽനിന്നുള്ള അൾട്രാവയലറ്റ് കിരണങ്ങളാൽ വിഘടിച്ച് ക്ലോറിൻ, ബാമിൻ തുടങ്ങിയ വാതക ങ്ങളായി മാറ്റപ്പെടുന്നു.

* ഈ വാതകങ്ങൾക്ക് ഓസോൺ തന്മാത്രകളെ വിഘടിപ്പിക്കാൻ കഴിയും.

19. ലോക ഓസോൺ ദിനമായി ആചരിക്കുന്നതെന്ന്? 

- സെപ്റ്റംബർ 16

20. എന്താണ് ക്രമമായ താപനഷ്ടനിരക്ക്?

ടോപോസ്ഫിയറിൽ ഓരോ 165 മീറ്റർ ഉയരത്തിനും ഒരു ഡിഗ്രി സെൽഷ്യസ് എന്ന തോതിൽ താപം കുറഞ്ഞു വരുന്നു. ഇതിനെ ക്രമമായ താപനഷ്ട നിരക്ക് എന്നു വിളിക്കുന്നു.

21. ഓരോ അന്തരീക്ഷമണ്ഡലത്തിൻ്റെയും സവിശേഷതകൾ പട്ടികപ്പെടുത്തുക.

The Blanket of the earth.

 

*THE BLANKET OF THE EARTH*

1. What is atmosphere?

■ Atmosphere is the blanket of air surrounding the earth.

2. Plants are significant in regulating the amount of oxygen and carbon dioxide in the atmosphere.

Justify

◻️Through the process of photosynthesis that the plants gather energy for their growth.

■ In this process plants intake carbon dioxide and give out oxygen.

3. What are the major constituents of atmosphere?

■ Gases, moisture and dust particles

4. What is the importance of oxygen, carbon dioxide and nitrogen in the existence of life forms.

■ Plants make use of Carbon dioxide for photosynthesis.

■ Man and other organisms make use of oxygen for respiration.

◻️Plants make use of nitrogen for their growth through nitrogen fixation.

5. What are the main sources of dust particles in the atmosphere?

◻️Dust particles brought to the atmosphere by wind.

■ Dust particles erupted through volcanoes.

◻️Ash formed by burning of meteors.

6. Why dust particles are called Condensation nuclei?

As the fine dust particles in the atmosphere help in cloud formation they are called as Condensation nuclei.

6. What is the significance of dust particles in the atmosphere.

◻️Frequent condensation concentrating around the fine dust particles in the atmosphere help in cloud formation

7. Why the mountaineers climbing Mount Everest take oxygen cylinders with them?

📚 The gases (oxygen) get rarefied with increasing altitude.

7. Why glass is largely used in the construction of buildings in cold countries?

❄️ Glass panes have the capacity to allow insolation to pass through them and check the terrestrial radiation.

❄️ Thus temperature is maintained within the buildings without fall. So feel hot.

8. How the property of glass is made use of in agricultural sector in cold countries?

📚  By preventing the terrestrial radiations the temperature required for the growth of plants is retained inside such constructions.

9. What are Green houses?

🌳 Greenhouses are glass buildings designed for the protection of plants against excessive cold or heat.

10. Write a short note on Greenhouse effect.

👉 Carbon dioxide, methane, ozone etc present in the atmosphere can permit insolation and prevents terrestrial radiation.

👉 These gases and water vapour present in the atmosphere absorb the terrestrial radiation and retain the temperature of the atmosphere. This phenomenon is called *Greenhouse effect*.

11. Give three examples of greenhouse gases.

☃️ Carbon dioxide, methane, ozone

12 . Write different sources of greenhouse gases.

🖊️ Volcanic eruptions,

🖊️ decay of biological matter (natural means)

🖊️Deforestation,

🖊️burning of fossil fuels  (human activities)

13. How deforestation leads to increase in the amount of carbon dioxide in the atmosphere?

■ Trees remove some of the carbon dioxide from the atmosphere through photosynthesis and store that carbon in their tissues and in the soil.

◻️ Deforestation reduces the removal component of this cycle, further increasing the carbon dioxide in the air.

14. What is Global warming?

The increase in temperature in the atmosphere due to greenhouse gases referred as Global warming.

15. How Global warming becomes a threat to the life forms of the earth?

◻️Sea level may rise as a result of melting of polar ice.

◻️ Destruction in the coastal ecosystem may lead to the problems such as food crisis, large scale migration etc.

◻️Leads to the depletion of many species of plants and animals in the ecosystem.

16. Suggest a few alternatives to resist global warming.

◻️ Drive fuel-efficient vehicles

■ Protect trees and forests

17. What is Ozone layer? Write its significance.

◻️As the ozone gas is concentrated in the upper atmosphere as a layer, it is called Ozone layer.

 ■ It protects the life forms of the earth by absorbing the harmful ultraviolet rays from the sun.

18. List out the negative impacts of ultraviolet rays.

■ Climate change

■ Blindness

■ Skin cancer

◻️ Premature ageing

■ Destruction in food chain



19. What are the sources of gases such as chlorofluorocarbons(CFC) , halon etc.?

■ Refrigerators, air conditioners, different types of sprays, fire extinguishers, paints, etc.

 20. How Ozone hole is formed?

📚 Gases like chlorofluorocarbons, halon etc rising to the upper atmosphere react with ultraviolet rays from the sun to form chlorine and bromine. 

◻️Chlorine and bromine are capable to decay ozone molecules.

◻️This depletion in the atmospheric ozone layer is called as Ozone hole.

21. Which day is celebrated as World Ozone Day? 

■ 16th September

22. What is Normal Lapse Rate?

◻️In the troposphere the temperature decreases at a uniform rate of 1°Celcius for every 165

metres of altitude. 

This is called *Normal Lapse Rate*.

23. Each layer in the atmosphere has its own indigenous characteristics. State the characteristics of each layer in a tabular format.

Election and democracy

              Chapter - 8

*ELECTION AND DEMOCRACY*

1. Write the importance of election?

📚 Election is the method by which the representatives of the people are elected in a democratic system.

📚 Without election, democratic system will not exist.

2. Write the importance of election in a democratic system?

◻️ Elections reflect the aspirations of the people.

■ People can select the rulers of their choice though elections.

◻️People can participate and respond in democratic process.

◻️ Election is a good reason for the rulers to act according to the aspirations of people.

3. Make a flow chart to show the method of election adopted to various Representative institutions of India.

*Direct Election*

◻️Lok Sabha
◻️State Legislative Assembly
◻️Local Self Governments

*Indirect Election*

◻️President
◻️Vice President
◻️Rajya Sabha

4. What is the difference between direct election and indirect election?

■ People directly electing their representatives is called direct election

• Eg: Lok Sabha election, Panchayat member.

◻️Method of election in which representatives are chosen by the elected representatives of people is indirect election.

Eg: Election of the President, Panchayat President.

5. Narrate the procedure of simple majority system.

◻️ The country is divided into various electoral districts known as constituencies.

◻️ One representative is elected from one constituency.

■ Any number of candidates can contest.

◻️ The candidate who gets the highest number of votes is elected.

6. Write short note about proportional Representation in India.

◻️Proportional representation is adopted to elect the President, Vice-President and members of the Rajya Sabha where we follow indirect election.

◻️MLAs of State Legislative Assemblies from each state elect members of the Rajyasabha.

◻️ In proportion to their strength in the state legislative assemblies, each political party can elect representatives to Rajya Sabha.

7. What are constituencies? Write any three features of it?

◻️ To elect people's representatives, the states and union territories are divided into small geographical areas.
These geographical areas are called constituencies.

◻️Each constituency has almost equal number of population.

◻️ 543 Lok Sabha constituencies in India.

◻️At present Kerala has 20 Lok Sabha Constituencies.

◻️ One representative is elected from each constituency.

8.  Write short note on Kerala's assembly constituencies.

◻️Each state has assembly constituencies in proportion to its population.

◻️At present Kerala has 140 Assembly Constituencies.

9. Write notes on reserved constituency.

◻️Ensure the representation of the weak and the oppressed section of the society.

◻️Accordingly seats have been reserved in Lok Sabha and State Assemblies for Scheduled Castes and Scheduled Tribes in proportion to their population.

◻️Only those who belong to the reserved category can contest in elections from the reserved constituencies.

◻️People belonging to various categories can cast their votes.

◻️At present, 84 seats are reserved for the Scheduled Castes and 47 seats for the Scheduled Tribes in the Lok Sabha.

10. What are the provisions included in the Constitution for a free and fair system of election in India.

◻️Universal adult franchise, right to contest in elections, independent election commission.

11. Explain universal adult franchise.

◻️ The right of all adult citizens to vote irrespective of caste, religion, race, language, sex,
place of birth, etc. is universal adult franchise.

■ In India, everyone who has attained 18 years of age has the right to vote.

12. How an Indian citizen can be enrolled in voters list ?

◻️Complete 18 years of age on January 1st.

◻️ Settle in a constituency for at least 6 months.

◻️Give application in form no. 6A.

13. Write the importance of Election Commission of India.

◻️A multi member body with one Chief Election Commissioner and two Commissioners.

◻️ They are appointed by the President.

◻️To help the election commission Chief Electoral Officers are appointed in all states.

◻️The Election Commission does not maintain many officials to conduct the elections.

◻️The central and state government employees are deputed for election duty whenever needed.

14. Point out the functions of Election Commission.

◻️Supervise the election.

◻️Prepare voters list.

◻️Declare the dates of different stages of election.

◻️ Allot election symbols.

◻️Frame code of conduct.

◻️The appointment and training of election officials.

◻️Voting, counting of votes and declaration of results.

◻️ Examine election expenses of candidates.

15. The electoral system of India has certain drawbacks. Mention

1). Influence of money.

■ Voters are influenced by offer of money.

◻️ Political parties spend large amount of money for election campaigns.

2) Election-related violence

■ Violence on the polling day.

◻️ Bogus voting and booth capturing.

3) Influence of caste and religion

• Caste and religious considerations influence selection of candidates.

4) Women do not get due consideration during the selection of candidates.

• Poor representation of women in the parliament and legislative assemblies.

16. Write the reforms implemented by the Election Commission to correct the election process.

◻️ Identity card with the voter's photo has been introduced.

◻️Limit has been set on the election expenses of candidates.

◻️Implemented code of conduct for political parties and candidates.

◻️ Electronic voting machine (E V M) has been introduced in elections.

◻️Published voters' list with photo of the electors.

◻️Negative voting system has been introduced.

17. Write down the main functions of political party?

◻️ Connect the government and the people.

◻️Form public opinion.

◻️ Create political awareness.

◻️Contest elections and the party attaining majority of seats form the government.

◻️ The parties which do not get majority of seats, functions as responsible opposition.

◻️ Correct the wrong policies of the government.

◻️ Put forward various policies and programmes.

18. Explain the words coalition politics and coalition government.

◻️ On occasion where no political party can get majority in elections, parties who can co- operate, form coalition fronts based on a common minimum programme and contest elections. This is coalition politics.

◻️ When such coalition fronts win the election and form government it is a coalition government.

19.  What is Psephology?

👉 Psephology is the science of predicting election results before the declaration of results, after analysing the possibilities of political parties and coalition fronts.
The results are predicted based on opinion polls, media analysis, interviews, exit polls and the previous election results.

 

വൈവിധ്യങ്ങളുടെ ഇന്ത്യ

#വൈവിധ്യങ്ങളുടെ ഇന്ത്യ 

📚 ഇന്ത്യയുടെ കാലാവസ്ഥയെ സ്വാധീനിക്കുന്ന ഘടകങ്ങൾ. 

◻️അക്ഷാംശ സ്ഥാനം

◻️ഭൂപ്രകൃതി

◻️സമുദ്രസാമീപ്യം

◻️സമുദ്രനിരപ്പിൽ നിന്നുള്ള ഉയരം

◻️കാറ്റുകൾ

◻️പർവ്വതങ്ങൾ

🔸ഇന്ത്യയിലെ ഋതുക്കൾ ഏവ?

1️⃣ശൈത്യകാലം

2️⃣ഉഷ്ണകാലം

3️⃣തെക്കുപടിഞ്ഞാറൻ മൺസൂൺ കാലം

4️⃣ വടക്കു കിഴക്കൻ മൺസൂൺ കാലം(മൺസൂണിന്റെ പിൻവാങ്ങൽ കാലം)

🔸 ഇന്ത്യയിലെ *ശൈത്യകാലത്തിന്റെ* സവിശേഷതകൾ.

◻️സൂര്യന്റെ ദക്ഷിണായന കാലത്താണ് ഇന്ത്യയിൽ ശൈത്യകാലം അനുഭവപ്പെടുന്നത്. 

◻️ഡിസംബർ, ജനുവരി, ഫെബ്രുവരി മാസങ്ങളിലാണ് ഇന്ത്യയിൽ ശൈത്യകാലം.

◻️പലഭാഗങ്ങളിലും കനത്ത മൂടൽമഞ്ഞും ഹിമാലയത്തിന്റെ താഴ്‌വരയില്‍  മഞ്ഞുവീഴ്ചയും ഉണ്ടാവുന്നു.

◻️ശൈത്യകാലത്ത് ഇന്ത്യയുടെ തെക്കുനിന്നും വടക്കോട്ട് പോകുന്തോറും താപനില കുറഞ്ഞു കുറഞ്ഞു വരുന്നു.

◻️ശൈത്യകാലത്ത് ഉത്തരേന്ത്യയിൽ പകൽസമയത്ത് മിതമായ ചൂടും രാത്രികാലങ്ങളിൽ തണുപ്പും

അനുഭവപ്പെടുന്നു.

ഈ കാലഘട്ടത്തിൽ അനുഭവപ്പെടുന്ന ഒരു പ്രതിഭാസമാണ് പശ്ചിമ അസ്വസ്ഥത.

🔸എന്താണ് പശ്ചിമ അസ്വസ്ഥത 

◻️ശൈത്യകാലത്ത് മെഡിറ്ററേനിയൻ കടലിൽ രൂപം കൊള്ളുന്ന ശക്തമായ ന്യൂനമർദ്ദം ക്രമേണ കിഴക്കോട്ട് നീങ്ങി ഇന്ത്യയിലെത്തുന്നു.

◻️ഇത് ഉത്തര മഹാസമതലപ്രദേശങ്ങളിൽ, പ്രത്യേകിച്ച് പഞ്ചാബിൽ ശൈത്യകാല മഴക്ക് കാരണമാകുന്നു.

 ◻️ഇതിനെയാണ് പശ്ചിമ അസ്വസ്ഥത എന്ന് അറിയപ്പെടുന്നത്.

◻️ടോപ്പോപ്പാസിലൂടെയുള്ള അതിശക്തമായ വായുപ്രവാഹമായ ജെറ്റ് പ്രവാഹമാണ് പശ്ചിമ അസ്വസ്ഥതയെ ഇന്ത്യയിലെത്തുന്നത്.

🔸 എന്താണ് *ഒക്ടോബർ* ചൂട് ?

ഒക്ടോബർ നവംബർ മാസങ്ങളിലായി ഇന്ത്യയൊട്ടാകെ അനുഭവപ്പെടുന്ന ഉയർന്ന ഊഷ്മാവും ആർദ്രതയും പകൽ സമയങ്ങളെ ദുസഹമാക്കുന്ന പ്രതിഭാസമാണ് *ഒക്ടോബർ ചൂട്*.

🔸 ഇന്ത്യയിലെ  *ഉഷ്ണകാലം*

മാർച്ച്, ഏപ്രിൽ, മെയ് മാസങ്ങളിലാണ് ഇന്ത്യയിൽ ഉഷ്ണകാലം അനുഭവപ്പെടുന്നത്.

സൂര്യന്റെ ഉത്തരായന കാലത്താണ് ഇന്ത്യയിൽ വേനൽക്കാലം അനുഭവപ്പെടുന്നത്.

🔸 *തെക്കുപടിഞ്ഞാറൻ മൺസൂൺ കാലം*

ഉത്തരാർദ്ധഗോളത്തിൽ വേനൽക്കാലത്ത് ഏതാണ്ട് മെയ് അവസാനം ഇന്ത്യയിൽ ഉത്തരമഹാസമതലത്തിൽ ശക്തമായ നൂനമർദ്ദം രൂപംകൊള്ളുന്നു.

◻️ഈ ന്യൂനമർദ്ദമേഖലയിലേക്ക് ദക്ഷിണാർദ്ധഗോളത്തിൽ വീശുന്നു തെക്കുകിഴക്കൻ വാണിജ്യവാതം ഭൂമധ്യരേഖ മുറിച്ച് കടക്കുന്ന തെക്കുകിഴക്കൻ വാണിജ്യ വാതങ്ങൾ ദിശാവ്യതിയാനം സംഭവിച്ച തെക്കുപടിഞ്ഞാറൻ മൺസൂൺ കാറ്റായി വീശുന്നു.

◻️തെക്കുപടിഞ്ഞാറൻ മൺസൂൺ കാറ്റുകളെ ഇന്ത്യൻ ഉപഭൂഖണ്ഡം

◻️ അറബിക്കടൽ ശാഖ എന്നും,

◻️ ബംഗാൾ ഉൾക്കടൽ ശാഖ എന്നും

രണ്ടായി വിഭജിക്കുന്നു.

 👉 *അറബിക്കടൽ ശാഖ*

◻️അറബിക്കടലിൽ നിന്നും നീരാവി വഹിച്ചുകൊണ്ട് വരുന്ന അറബിക്കടൽ ശാഖ പശ്ചിമഘട്ടത്തിന്റെ

പടിഞ്ഞാറുഭാഗത്ത് തട്ടി ഉയർന്നുപൊങ്ങി മഴയായ് പശ്ചിമഘട്ടത്തിന്റെ പടിഞ്ഞാറുഭാഗത്ത് പെയ്തിറങ്ങുന്നു.

◻️കേരളം, ഗോവ, മഹാരാഷ്ട്ര, ഗുജറാത്ത് എന്നീ സംസ്ഥാനങ്ങളിൽ മഴപെയ്യിക്കുന്നു.

👉 *ബംഗാൾ ഉൾക്കടൽ ശാഖ*

◻️ബംഗാൾ ഉൾക്കടലിൽ നിന്നും നീരാവി വഹിച്ചെത്തുന്ന ഈ ശാഖ പൂർവ്വ ഘട്ടത്തിനു സമാന്തരമായി വടക്കോട്ട് സഞ്ചരിച്ച് ഹിമാലയ 

പർവ്വതത്തിൽ തട്ടി രണ്ടായി പിരിയുന്നു.

🔸 *മൺസൂണിന്റെ പിൻവാങ്ങൽ കാലം* (വടക്കുകിഴക്കൻ മൺസൂൺ കാറ്റുകൾ)

◻️സെപ്റ്റംബർ, ഒക്ടോബർ മാസങ്ങളിലാണ് വടക്കു കിഴക്കൻ മൺസൂൺ കാലം അനുഭവപ്പെടുന്നത്.

◻️വടക്കു കിഴക്കൻ മൺസൂൺ കാറ്റുകൾ വരണ്ട കാറ്റുകൾ ആയതിനാൽ ഇത് ഇന്ത്യയിൽ പൊതുവെ മഴ ഉണ്ടാക്കാറില്ല.

 മൺസൂണിന്റെ പിൻവാങ്ങൽ കാലമെന്നും വിശേഷിപ്പിക്കാറുണ്ട്.

മഴക്കാലത്തിനും ശൈത്യകാലത്തിനും ഇടയിലുള്ള ഇടവേളയാണിത്.

 ◻️  തമിഴ്നാട് തീരത്ത് കനത്ത മഴക്ക് കാരണമാകുന്നു.

❓ കേരളത്തിൽ വടക്കുകിഴക്കൻ മൺസൂൺ കാലം അറിയപ്പെടുന്നത് *തുലാവർഷം* എന്നാണ്.

India : The land of diversities

 *India: The Land of Diversities*

India Physiographic divisions

 1️⃣ Northern Mountain Ranges 

2️⃣ Northern Great Plains        

  3️⃣ Peninsular plateau

4️⃣ Coastal plain -Islands

📚 Northern Mountain Ranges

👉 In Northern mountain region there are three mountain ranges

They are:-

A) Trans Himalayas

B) Himalayas

C) Eastern Highlands

A) Trans Himalayas

✍🏻 Trans Himalayas include *Karakoram, Ladakh, and Zaskar* mountain ranges.

 ✍🏻 Mount K2 (8661m) also known as Godwin Austin, the highest peak in India, is in the Karakoram range. -The average height of the Trans Himalayas is 6000 meters.

B) Himalayas

✍🏻 The Himalayan mountain range forms an are shaped physical division extending between the north-west trans himalayas and the south-east eastern highlands.

✍🏻 These mountain ranges have a length of about 2400 kilometers.

✍🏻 Many of the world's highest peaks are situated here.

✍🏻 The height of these mountains tend to decrease towards the east.

👉 Himalayan ranges are divided in to three. They are:-

◻️Himadri,

◻️Himachal,

◻️Siwaliks.

👉 *Himadri*

◻️ The highest mountain range.

◻️ Average altitude is 6000 meters.

◻️ Origin of the rivers Ganga and Brahmaputra.

.

◻️Has a number of peaks above 8000 meters (Eg: Kanchenjunga, Nandadevi)

👉 *Himachal*

◻️Situated to the south of the Himadri.

◻️Average altitude is 3000 meters.

◻️The hill stations like Shimla, Darjeeling, etc. are situated in the southern slopes of this range.

👉 *Siwaliks*

◻️ Situated to the south of the Himachal.

◻️Average altitude is 1220 meters.

◻️ As the Himalayan rivers cut across this range, its continuity breaks at many places.

◻️Broad flat valleys seen along these ranges are called Duns. (Eg: Dehradun).

👉 *Human life in the lap of the Himalayas*

✍🏻 The major means of livelihood is animal rearing that depends purely on the grasslands here.

 ✍🏻 Sheep are commercially reared in Kashmir and Himachal.

✍🏻 Potato, barley, and saffron, fruits like apple and orange are cultivated in Siwalik valleys.

✍🏻 The largest production of tea in India comes from Assam mountain ranges.

✍🏻 Hill stations like Shimla, Darjeeling, Kulu, Manali, etc. are situated here.

*Eastern Highlands*

◻️This region which is at an altitude of 500 to 3000 meters is also known as Purvachal.

 ◻️Cherrapunji, the place receiving the highest rainfall in the world is situated here.

◻️This region is covered by dense tropical rain forests.

Major mountains in Eastern Highlands.

(1) Patkai Bum-Nagaland

 (2) Naga hills-Nagaland

(3) Garo, Khasi, and Jaintia hills-Meghalaya

(4) Mizo hills-Mizoram

*Significance of the Northern Mountains*

◻️Have been protecting us from foreign invasions from the north since ancient times.

◻️ Block the monsoon winds and cause rainfall throughout North India.

◻️ Caused the emergence of diverse flora and fauna.

◻️Source region of rivers.

Indian rivers.

 *Northern Great Plains*

◽During the formation of the Himalayas, a huge depression of more than 2000 metre depth took shape along the south parallel to the Himalayas.

◽This extensive plain took shape as a result of the continuous deposition by the rivers flowing down from the Himalayas for thousands of years. 

◽This plain, extending over seven lakh square kilometres and with kilometres of thick sediments, is one among the few extensive alluvial plains of the world.

◽This plain is generally known as the Indus-Ganga-Brahmaputra plain.

◽The highly fertile alluvial soil is a characteristic feature of this plain.

◽The granary of India. 

◽A variety of crops such as wheat, maize, rice, sugar cane, cotton, pulses, etc. Cultivated in Northern Great Plains. 

◽This region is known as the granary of India.

◽The Northern Great Plain is one of the most densely populated regions in the world.

📚 *Thar Desert*

✍🏻 Rainfall is scarce along the western parts of the northern plains.

✍🏻 That is why most regions in Rajasthan are deserts.

✍🏻 This desert is known as Thar Desert.

✍🏻 River Luni and the long vanished river Saraswathy have had significant role in the formation this portion of the plain.

✍🏻 Dry and salty desert soil is found in this Region.

✍🏻 Thorns and bushes form the natural vegetation here.

What are the main crops cultivated in Rajasthan.

 -Bajra,

-Jowar,

✍🏻 These crops require very little amount of water to grow. 

✍🏻 Here cultivation is done mainly with the help of irrigation.

👉 *The Peninsular Plateau*

📚 Entire portions of Madhya Pradesh, Jharkhand and Chhattisgarh as well as parts of Maharashtra, Karnataka, Tamil Nadu, Telengana, Odisha and West Bengal together form a plateau known as the *peninsular plateau*.

📚 The peninsular plateau made of hard crystalline rocks forms the oldest and the most extensive physical division of India.

📚 It extends about 15 lakh square kilometres.

📚 The highest peak in this region is the Anamudi (2695 m) situated in the Idukki district of Kerala.

 📚 As the peninsular plateau holds numerous deposits of diverse minerals, this region can be termed as the *Store house of minerals*.

📚 The trees found in this region are teak, sal, sandalwood, bamboo, etc.

 📚 Black soil is extensively found in this region made of igneous rocks, named basalt.

 📚 As this soil is best suited for cotton cultivation, it is also called *black cotton soil*.

📚 *Red soil also formed by the weathering of igneous and metamorphic rocks is comparatively less fertile*.

📚 The presence of iron gives red colour to this soil.

👉 *Peninsular Rivers*

◽The rivers originating from the elevated regions of the peninsular plateau are known as peninsular rivers.

◽Peninsular Rivers are divided in to two:-

◽West flowing rivers- Narmada & Tapti.

◽East flowing rivers-Mahanadi, Godavari, Krishna & Cauvery.

◽Godavari is the longest among the peninsular rivers.

◽Waterfalls are common in most of the peninsularrivers.

◽The highest among these is the Jog Falls (225 metres).

◽Cotton, pulses, groundnut, sugarcane, maize, ragi, chilli, etc., are the major agricultural crops of this region.

◽Iron ore, coal, manganese, bauxite, limestone, etc. are the major minerals found here.

◽Hence agriculture, mining, and mineral based industries are the major economic activities.

👉 *Coastal plain of India*

✍🏻 The approximate length of this coast line is 6100 kilometres extending from the Rann of Kutchh in Gujarat to the Ganga-Brahmaputra delta.

✍🏻 The coastal plain of India can be divided into two. 

They are:

✅ *Western coastal plain*

◽Western coastal plain

Between the Arabian Sea and the

Western Ghats. 

◽From the Rann of Kutchh to Kanyakumari. 

◽Comparatively narrow

Can be divided into Gujarat coast, Konkan coast, and Malabar coast. 

◽Backwaters and esturies are seen. 

✅ *Eastern coastal plain*

◽Between the Bay of Bengal and theEastern Ghats. 

◽From the Sundarban delta region to Kanyakumari. 

◽Comparatively wide. 

◽Can be divided into north Zircar plain and Coromandal coast. 

◽Delta formation takes place. 

❓Main occupation of the 

people in the coastal plains.

◽Fishing

◽Tourism

◽Rice and coconut are the major agricultural crops along the west coast.

👉 *Major islands in India*

1️⃣ *The Lakshadweep islands*

2️⃣ *The Andaman and Nicobar islands* . 

*The Lakshadweep islands*

⚽ The Lakshadweep islands are situated in the Arabian Sea at a distance of about 300 kilometers off shore from Kochi.

⚽ There are 36 islands in this island group, of which only 11 are inhabited.

⚽ Kavarathi is the capital of Lakshadweep.

⚽ Lagoons, sandy beaches and coral reefs are the specialities of the Lakshadweep island group.

 

⚽ Fishing and tourism are the major sources of income.

*The Andaman and Nicobar islands*

⚽ The Andaman and Nicobar islands include about 200 islands of Andaman group and 19 islands of Nicobar group.

⚽ Most of these islands are not inhabited.

⚽ Many of them have dense forests.

⚽ The only volcano in India is situated in the Barren Island here.

⚽ Port Blair is the capital of Andaman and Nicobar islands.

*Himalayan rivers*

◻️Himalayan rivers

Originate from the Himalayan mountain

ranges. 

◻️Extensive catchment area. 

◻️Intensive erosion

◻️High irrigation potential. 

◻️Navigable along the plains. 

*Peninsular rivers*

🔸Originate from the mountain ranges in the peninsular plateau.

🔸Comparatively smaller catchment area. 

 

🔸Intensity of erosion is less. 

🔸Less irrigation potential. 

🔸 Potential for inland navigation is low

✒️ The factors influencing the climate of India. 

◻️Latitude

◻️Physiography

◻️Nearness to sea

◻️Altitude

◻️Mountains

◻️Winds

🔸The seasons in India can be generally classified into four.

1️⃣ *Cold weather season In India* (Winter)

◻️India experiences winter when the position of the sun is over the southern hemisphere.

◻️Most places in India experience intense fog and snowfall occurs in the valleys of the Himalayas during this season.

◻️The months of December, January, and February experienced cold weather in India.

◻️During the cold weather season days are generally warm and nights are severely cold in North India.

 ◻️Snowfall is a common phenomenon in the hill stations like Manali and Shimla.

❓What is Western Disturbance. 

◻️The cyclones originating in the Mediterranean Sea during winter, gradually shifts towards the east and reaches India.

This causes winter rainfall in the northern plains, especially in the Punjab region.

The phenomenon is called  *western disturbance* .

2️⃣ *Hot weather season* (Summer)

◻️India experiences hot weather when the sun is over the northern hemisphere. 

◻️In the months of March, April and May experienced Summer season in India. 

◻️It is in Barmer in western Rajasthan that the highest temperature of summer is felt.

 ◻️Loo, mango showers, etc. are some local winds experienced in India during this season.

3️⃣ *South west monsoon season*

◻️When the sun is over the northern hemisphere, North Indian regions experience intense low pressure. 

◻️In the months of June, July, August and September India experience south west monsoon season.

 ◻️Owing to the high pressure over the oceans, wind blows from high pressure to low pressure regions, that is, from the Indian Ocean to the Indian sub-continent.

◻️As the winds deflect towards right due to coriolis effect, they reach India as southwest monsoon winds.

 ◻️Because of the peculiar shape of the Indian peninsula, the southwest monsoon winds bifurcate into two branches on entering the land.

👉 *Arabian Sea branch*

👉 *Bay of Bengal branch*

◻️The Arabian Sea branch that reaches the coast of Kerala by early June causes heavy rainfall here. 

◻️The Arabian Sea branch of south west monsoon that reaches the coast of Kerala by early June causes heavy rainfall here.

◻️Then it advances to the states of Karnataka, Goa, Maharashtra, and Gujarat and causes rainfall in the western parts.

❓By what name is the southwest monsoon rain known in Kerala?

- *Edavappaathi*

👉 *Bay of Bengal branch*

◻️The Bay of Bengal branch of the monsoon advances northward by absorbing more moisture from the Bay of Bengal.

◻️On reaching West Bengal, crossing the Sundarban delta, it bifurcates into two branches.

◻️One branch reaches the northeastern states through the Brahmaputhra plains and causes heavy rainfall there.

◻️The other branch enters the Ganga plains and causes rainfall in West Bengal, Bihar, Uttar Pradesh, etc.

 ◻️This branch merging with the Arabian Sea branch in the Punjab plains advances north further and causes heavy rainfall along the foothills of the Himalayas.

 4️⃣ *Retreating monsoon season* (North East Monsoon)

◻️By the end of September, as the sun apparently shifts towards the southern hemisphere, intense high pressure develops over the northern plains.

◻️Comparatively low pressure over the Indian Ocean causes wind to blow from the northern part of India towards the Indian Ocean.

◻️These winds known as north-east monsoon winds are dry winds that do not generally cause any rain in India.

◻️This season termed as north east monsoon. 

◻️This season is actually a transition period between the rainy season and the forth coming winter

 ◻️This season experienced during the months of October and November.

◻️This season termed as north east monsoon. 

◻️This season is actually a transition period between the rainy season and the forth coming winter. 

◻️This season experienced during the months of October and November.

◻️This is the main rainy season of Tamil Nadu. 

👉 *October heat*

◻️The days in October and November unbearable due to high temperature and humidity. 

◻️This phenomenon is known as October heat.

❓By what name is the northeast monsoon rain known in Kerala?

*Thulaavarsham*