Population growth, distribution and density

 

India is the second most populous country in the world next only to China. On March 1, 2011 the total population of India was at 1.247 billion. This accounted for 17.5% of the world’s total population. In other words, about every sixth person in the world there is an Indian. China, the most populous country of the world, is a step ahead of us as every fifth person in the world there is a Chinese. While India possesses only 2.42% of the world’s total land area, she is required to sustain almost 17.5% of the world’s population.

Two components of population growth are: Natural growth: It is analysed by assessing the crude birth and death rates. Induced growth: It is assessed by the volume of inward and outward movement of people in any given area. There are four phases of population growth in India. The period from 1901-1921 is referred to as a period of stagnant growth of India’s population. The high birth rate was counterbalanced by high death rate. The decades 1921-1951 are referred to as the period of steady population growth. The mortality rate started showing downward trend as a result of improvement in general health and sanitation conditions after 1921.

The density of population is expressed as the number of persons per square kilometre. According to 2011 census, the density of population in India is 382 persons per square kilometre. Over the last 100 years density has increased more than four times.

Density and its variation across states can be accessed by the following table:-

State Area Sq. Km Density 2011 Density 2001 Density

2011

India (Average) 3,287,240 382 324
1 Delhi 1,483 11,320 9,340
2 Chandigarh 114 9,258 7,900
3 Puducherry 490 2,547 2,034
4 Daman and Diu 111 2,191 1,413
5 Lakshadweep 30 2,149 1,895
6 Bihar 94,163 1,106 881
7 West Bengal 88,752 1,028 903
8 Kerala 38,852 860 819
9 Uttar Pradesh 240,928 829 690
10 Dadra and Nagar Haveli 491 700 449
11 Haryana 44,212 573 478
12 Tamil Nadu 130,060 555 480
13 Punjab 50,362 551 484
14 Jharkhand 79,716 414 338
15 Assam 78,438 398 340
16 Goa 3,702 394 364
17 Maharashtra 307,713 365 315
18 Tripura 10,486 350 305
19 Karnataka 191,791 319 276
20 Gujarat 196,244 308 258
21 Andhra Pradesh 275,045 308 277
22 Orissa 155,707 270 236
23 Madhya Pradesh 308,252 236 196
24 Rajasthan 342,239 200 165
25 Uttarakhand 53,483 189 159
26 Chhattisgarh 135,192 189 154
27 Meghalaya 22,429 132 103
28 Manipur 22,327 128 103
29 Himachal Pradesh 55,673 123 109
30 Nagaland 16,579 119 120
31 Sikkim 7,096 86 76
32 Jammu and Kashmir 222,236 56 46
33 Mizoram 21,081 52 42
34 Andaman and Nicobar Islands 8,249 46 43
35 Arunachal Pradesh 83,743 17 13

 

 

 

 

 

Natural Hazards : Floods, Droughts, Cyclones, Landslides

 

Natural Hazards of India

Disaster

A disaster is a sudden, calamitous event that seriously disrupts the functioning of a community or society and causes human, material and economic or environmental losses that exceed the community’s capacity to cope using its own resources.

Vulnerability + Hazard =Disaster

Vulnerability- it is defined as the diminished capacity of an individual or group to anticipate, copes with, resist and recover from the impact of a natural or manmade hazard.

Types of Disaster

Hazards are routinely divided into natural or manmade, although complex disasters, where there is no single root cause, are more common in developing countries. A specific disaster may spawn a secondary disaster. A classical example is Earthquake that cause Tsunami that results in coastal flooding.

Natural Hazards

Natural Hazards are naturally occurring physical phenomenon caused either by rapid or slow onset events which can be

  • Geophysical– Earthquakes, landslides, tsunamis and volcanic activity
  • Hydrological– Avalanches and Floods
  • Climatological- extreme temperatures, drought and wildfires
  • Meteorological– Cyclones and storms
  • Biological- epidemics and animal plagues

Natural Disasters and Aggravating Factors

Although these hazards are natural but there are certain aggravating factors which will result in increased frequency, complexity and severity of disasters. These factors are

  • Climate change
  • Unplanned urbanisation
  • Under development
  • Poverty
  • Pandemics

Earthquakes

Earthquakes are tectonic in origin; that is the moving plates are responsible for the occurrence of violent shakes. The occurrence of an earthquake in a populated area may cause numerous casualties and injuries as well as extensive damage to property.

The Earthquake Risk in India

India’s increasing population and extensive unscientific constructions mushrooming all over, including multistoried luxury apartments, huge factory buildings, gigantic malls, supermarkets as well as warehouses and masonry buildings keep – India at high risk. During the last 15 years, the country has experienced 10 major earthquakes that have resulted in over 20,000 deaths.

 

As per the current seismic zone map of the country, over 59 per cent of India’s land area is under threat of moderate to severe seismic hazard-; that means it is prone to shaking of MSK Intensity VII and above In fact, the entire Himalayan belt is considered prone to great earthquakes of magnitude exceeding 8.0-; and in a relatively short span of about 50 years, four such earthquakes have occurred: 1897 Shillong (M8.7); 1905 Kangra (M8.0); 1934 Bihar-Nepal (M8.3); and 1950 Assam-Tibet (M8.6). Scientific publications have warned of the likelihood of the occurrence of very severe earthquakes in the Himalayan region, which could adversely affect the lives of several million people in India.

 

 

In our present state of knowledge, earthquakes can neither be prevented nor predicted in terms of their magnitude, or place and time of occurrence. Therefore the most effective measures of risk reduction are pre disaster mitigation, preparedness and preventive measures.

Govt efforts

  • National Earthquake Mitigation Project – it aims at strengthening the structural and non structural earthquake mitigation efforts and reducing the vulnerability in high risk areas.
  • National Building Code- a national instrument providing guidelines for regulating the building construction activities.
  • Building Material & Technology promotion council
  • Institutional arrangements like NDMA
  • Capacity building
  • Retrofitting

Floods

Floods have been recurrent phenomenon in many parts of India, causing loss of lives and public property and bringing untold misery to the people, especially those in the rural areas. There is also a larger economic impact, as they derail economic activities, thus affecting growth. Indian continent has peculiar climatic conditions since it has floods in some parts whereas drought in other parts.

Over the years, several expert Committees have studied the problems caused by floods and suggested various measures for their management to the Government. However, despite the various steps undertaken over the last five decades, the trend of increasing damage and devastation brought by floods has posed a challenge to the Government as well as to the people. The approaches to flood management presently exercised in India also need to give a re-look to have an integrated strategy for policy and management related to floods.

Brahmaputra River Region:

This region consists of the rivers Brahmaputra & Barak and their tributaries covering seven states .The catchments of these rivers receive very heavy rainfall ranging from 110 cm. to 635 cm. a year which occurs mostly during the months of May / June to September. As a result, floods in this region are severe and quite frequent.

Ganga River Region:

The river Ganga and its numerous tributaries, of which important ones are the Yamuna, the Sone, the Ghaghra, the Gandak, the Kosi and the Mahananda, constitute this river region. The flood problem is mostly confined to the areas on the northern bank of the river Ganga. The damage is caused by the northern tributaries of the Ganga by spilling over their banks and changing their courses.
North West River Region:

The main rivers in this region are the Sutlej, the Beas, the Ravi, the Chenab and the Jhelum, the tributaries of Indus, all flowing from the Himalayas. These carry quite substantial discharge during the monsoon and also large volumes of sediment. They change their courses frequently and leave behind tracts of sandy waste. Compared to the Ganga and the Brahmaputra river region, the flood problem is relatively less in this region. The major problem is that of inadequate surface drainage which causes inundation and water logging over vast areas.
Central India and Deccan Region:

The important rivers in this region are the Narmada, the Tapi , the Mahanadi, the Godavari, the Krishna and the Cauvery. These rivers have mostly well defined stable courses. They have adequate capacity within the natural banks to carry the flood discharge except in the delta area. The lower reaches of the important rivers on the East Coast have been embanked, thus largely eliminating the flood problem.

Flood management measures in India

Different measures have been adopted to reduce the flood losses and protect the flood plains. Depending upon the nature work, Flood protection and flood management measures may be broadly classified as under:

(a) Engineering / Structural Measures

The engineering measures for flood control which bring relief to the flood prone areas by reducing flood flows and thereby the flood levels are –

(a) an artificially created reservoir behind a dam across a river

(b) a natural depression suitably improved and regulated, if necessary or

(c) by diversion of a part of the peak flow to another river or basin, where such diversion would not cause appreciable damage.

(d) by constructing a parallel channel bye passing a particular town/reach of the river prone to flooding.

The engineering methods of flood protection, which do not reduce the flood flow but reduce spilling, are:

(a) embankments which artificially raise the effective river bank and thereby prevent spilling and

(b) channel and drainage improvement works, which artificially reduce the flood water level so as to keep the same, confined within the river banks and thus prevent spilling.

Administrative methods

The administrative methods endeavour to mitigate the flood damages by;

(a) Facilitating timely evacuation of the people and shifting of their movable property to safer grounds by having advance warning of incoming flood i.e. flood forecasting, flood warning in case of threatened inundation

(b) Discouraging creation of valuable assets/settlement of the people in the areas subject to frequent flooding i.e. enforcing flood plain zoning regulation.

Landslides

the northward movement of the Indian plate towards China causes continuous stress on the rocks rendering them friable, weak and prone to landslides and earthquakes. The slow motion of the Indian crust, about 5 cm/year accumulates stress to which natural disasters are attributed. Some landslides make unique, and unparalleled catastrophes. Landslides and avalanches are among the major hydro-geological hazards that affect large parts of India besides the Himalayas, the Northeastern hill ranges, the Western Ghats, the Nilgiris, the Eastern Ghats and the Vindhyans, in that order, covering about 15 % of the landmass. The Himalayas alone count for landslides of every fame, name and description- big and small, quick and creeping, ancient and new.

 

The Northeastern region is badly affected by landslide problems of a bewildering variety. Landslides in the Darjeeling district of West Bengal as also those in Sikkim, Mizoram, Tripura, Meghalaya, Assam, Nagaland and Arunachal Pradesh pose chronic problems, causing recurring economic losses worth billions of rupees. A different variety of landslides, characterized by a lateritic cap, pose constant threat to the Western Ghats in the South, along the steep slopes overlooking the Konkan coast besides Nilgiris, which is highly landslide prone.

 

Some spectacular events of tragedies are reported as Varnavat landslide, Uttarkashi District, Malpha landslide Pithoragarh district, Okhimath landslide in Chamoli district, UK and Paglajhora in Darjeeling district as well as Sikkim, Aizawl sports complex, Mizoram.These are some of the more recent examples of landslides. The problem therefore needs to be tackled for mitigation and management for which hazard zones have to be identified and specific slides to be stabilized and managed in addition to monitoring and early warning systems to

 

Remedial Measures

  • Afforestation
  • Use of geo textiles which reduces slope instability
  • Making community aware about impact of landslides and build their capacity to reduce vulnerability
  • Proper mapping of Landslide zone and shifting people from such zones
  • No mining activities should be allowed in Eco sensitive zones

Cyclones

Cyclones are caused by atmospheric disturbances around a low-pressure area distinguished by swift and often destructive air circulation. Cyclones are usually accompanied by violent storms and bad weather. The air circulates inward in an anticlockwise direction in the Northern hemisphere and clockwise in the Southern hemisphere. Cyclones are classified as: (i) extra tropical cyclones (also called temperate cyclones); and (ii) tropical cyclones.

The Indian subcontinent is one of the worst affected regions in the world. The subcontinent with a long coastline of 8041 kilometres is exposed to nearly 10 per cent of the world’s tropical cyclones. Of these, the majority of them have their initial genesis over the Bay of Bengal and strike the East coast of India. On an average, five to six tropical cyclones form every year, of which two or three could be severe. More cyclones occur in the Bay of Bengal than the Arabian Sea and the ratio is approximately 4:1.

Tropical cyclones occur in the months of May-June and October-November. Cyclones of severe intensity and frequency in the North Indian Ocean are bi-modal in character, with their primary peak in November and secondary peak in May. The disaster potential is particularly high during landfall in the North Indian Ocean (Bay of Bengal and the Arabian Sea) due to the accompanying destructive wind, storm surges and torrential rainfall. Of these, storm surges cause the most damage as sea water inundates low lying areas of coastal regions and causes heavy floods, erodes beaches and embankments, destroys vegetation and reduces soil fertility.

Remedial measures

  • Early warning and Communication- inform those who are likely to be affected and disseminate the information by AIR, Door Darshan, local community radio etc.
  • Capacity Building among people and educate people on various aspects of disaster management.
  • Storm Shelters- with full amenities for both Humans and Animals
  • Bio shields- vegetation, trees, shrubs which develops near the coast, they protect from strong storms and winds.
  • Integrated development of coastal areas with strong infrastructure.

DROUGHT

It is difficult to provide a precise and universally accepted definition of drought due to its varying characteristics and impacts across different regions such as rainfall patterns, human response and resilience etc. Drought is a normal, recurrent feature of climate and occurs in all climatic regimes and is usually characterized in terms of its spatial extension, intensity and duration. Drought causes economic, environmental and social impacts.

Ministry of Agriculture is the nodal Ministry in respect of monitoring and managing drought conditions and droughts are classified into meteorological droughts, hydrological droughts and agricultural droughts.

Meteorological drought is classified based on rainfall deficiency w.r.t. long term average – 25% or less is normal, 26-50% is moderate and more than 50% is severe.

Hydrological drought is best defined as deficiencies in surface and sub-surface water supplies leading to a lack of water for normal and specific needs. Such conditions arise even in times of average (or above average) precipitation when increased usage of water diminishes the reserves.

Agricultural drought is identified by 4 consecutive weeks of meteorological drought, weekly rainfall is 50 mm from 15/5/ to 15/10, 6 such consecutive weeks rest of the year and crop planted is 80% in kharif season.

In India, around 68% of the country is prone to drought in varying degrees. 35% which receives rainfall between 750 mm and 1125 mm is considered drought prone while 33% receiving less than 750 mm is chronically drought prone.

National Disaster Management Guidelines on Management of Drought

  • The NDMA guidelines on management of drought are issued in 2010. The recommendations are as follows:
  • Creation of Drought Monitoring Cells (DMCs) cells at state level with requisite staff.
  • Preparation of vulnerability maps for each state by the State DMCs. Development of real-time drought related information by using information and communication technology.
  • The watershed development approach would be taken up for drought management.
  • Assessment of damage would include agricultural production, depletion of water resources, livestock population, land degradation and deforestation as well as human health.
  • Revamping of Drought Management Information System of Department of Agriculture.
  • To enable micro level analysis and forecasting, automatic weather station and rain-gauges to be put in place.
  • Development of drought resistant crop varieties through large scale research.
  • Formulation of a cloud seeding policy.
  • Promoting crop diversification through sprinklers/Drip irrigation systems (micro irrigation techniques) etc.

Cloud Bursts

Highly concentrated rainfall over a small area lasting for a few minutes to few hours is called a cloud burst. It leads to sudden flash floods and landslides in which houses collapse and ultimately results in human casualties on a large scale.

Cloud bursts are manifestations of an intense whirling mass of fluid, on small scale, that generate strong currents, which lift the moisture laden air with sufficient rapidity to form dense towering vertical clouds which are capable of shedding water load with great strength and ferocity.

Steep hills favour the formation of these clouds. Also, water flowing down steep slopes brings debris, boulders and uprooted trees with great velocity, damaging any structure that comes in the way.

There is no satisfactory technique for anticipating a cloud burst because they occur in relatively small scale. A very fine network of radars is required to detect the likelihood of a cloud burst which could be very expensive.Cloud bursts causes landslides and flooding.

Tsunami

A tsunami (pronounced su-nah-me) is a wave train, or series of waves, generated in a body of water by an impulsive disturbance that vertically displaces the water column. Earthquakes, landslides, volcanic eruptions, explosions, and even the impact of cosmic bodies, such as meteorites, can generate tsunamis. Tsunamis can savagely attack coastlines, causing devastating property damage and loss of life.

The tsunami that occurred during 2004 Sumatra-Andaman earthquake of Mw 9.3 was primarily caused by vertical displacement of the seafloor, in response to slip on the inter-plate thrust fault.  The earthquake and resulting tsunami in the Indian Ocean affected many countries in Southeast Asia and beyond, including Indonesia, Sri Lanka, India, Thailand, the Maldives, Somalia, Myanmar, Malaysia, Seychelles and others.

The Government of India has put in place an Early Warning System for mitigation of such oceanogenic disasters under the control of Indian National Center for Ocean Information Services (INCOIS), Hyderabad. A state-of-the-art early warning centre was established with the necessary computational and communication infrastructure that enables reception of real-time data from  sensors, analysis of the data, generation and dissemination of tsunami advisories following a standard operating procedure.

The 2004 tsunami also prompted NDMA to formulate Tsunami Risk Management Guidelines to outline inter-agency roles and responsibilities, tsunami risk preparedness, mitigation and response.

The Guidelines recommends practical and effective ways for awareness generation, capacity building, education, training and research & development for better tsunami risk management.  The Guidelines explore options for effective dissemination of tsunami alert and warning messages generated by INCOIS to the concerned agencies and coastal vulnerable communities exposed to tsunamis in a coordinated manner.

 

Heat Wave

A Heat Wave is a period of abnormally high temperatures, more than the normal maximum temperature that occurs during the summer season in the North-Western parts of India. Heat Waves typically occur between March and June, and in some rare cases even extend till July. The extreme temperatures and resultant atmospheric conditions adversely affect people living in these regions as they cause physiological stress, sometimes resulting in death.

 

Higher daily peak temperatures and longer, more intense heat waves are becomingly increasingly frequent globally due to climate change. India too is feeling the impact of climate change in terms of increased instances of heat waves which are more intense in nature with each passing year, and have a devastating impact on human health thereby increasing the number of heat wave casualties.

Health Impacts of Heat Waves

The health impacts of Heat Waves typically involve dehydration, heat cramps, heat exhaustion and/or heat stroke. The signs and symptoms are as follows:

  • Heat Cramps: Ederna (swelling) and Syncope (Fainting) generally accompanied by fever below 39*C i.e.102*F.
  • Heat Exhaustion: Fatigue, weakness, dizziness, headache, nausea, vomiting, muscle cramps and sweating.
  • Heat Stoke: Body temperatures of 40*C i.e. 104*F or more along with delirium, seizures or coma. This is a potential fatal condition

Major types of Soils.(ICAR classification) and their distribution. Soil degradation and conservation

 

Soil is defined as upper layer of the earth composed of loose surface material. It is a mixture of many substances including endless variety of minerals, remnants of plants and animals, water and air. It is the end product of continuing interaction between the parent material, local climate, plant and animal organisms and elevation of land. Since each of the elements varies over space, soils also differ from place to place. Soil is an important segment of our ecosystem, as it serves an anchorage for plants and source of nutrients. Thus, soil is the seat, the medium and fundamental raw material for plant growth.
Soils are formed from materials that have resulted from the disintegration of rocks by various processes of physical and chemical weathering. The nature and structure of a given soil depends on the processes and conditions that formed it:

  • Breakdown of parent rock: weathering, decomposition, erosion.
  • Transportation to site of final deposition: gravity, flowing water, ice, wind.
  • Environment of final deposition: flood plain, river terrace, glacial moraine, lacustrine or marine.
  • Subsequent conditions of loading and drainage: little or no surcharge, heavy surcharge due to ice or overlying deposits, change from saline to freshwater, leaching, contamination.

According to ICAR Indian soils are classified as:-

  • Alluvial soils:-Alluvial soils are formed mainly due to silt deposited by Indo Gangetic Brahmaputra rivers. In coastal regions some alluvial deposits are formed due to wave action.
  • Black soils:-The black soils are found mainly on the Deccan lava region covering large parts of Maharashtra, some parts of Gujarat and Madhya Pradesh and small parts of Karnataka, Andhra Pradesh and Tamil Nadu. The soils are formed by disintegration of volcanic basaltic lava. The colour of the soil is generally black due to presence of compounds of aluminium and iron.
  • Red soils:- these soils are light textured with porous and friable structure and there is absence of lime Kankar and free carbonates. They have neutral to acidic reaction and are deficient in nitrogen humus, phosphoric acid and lime.
  • Laterite and Lateritic soils:-These soils are red to reddish yellow in colour and low in N, P, K, lime and magnesia. These soils are formed in-situ under conditions of high rainfall with alternation dry and wet periods. On account of heavy rainfall there is an excessive leaching of soil colloids and silica hence the soils are porous.
  • Forest and Mountain soils:-These soils occur at high elevations as well as at low elevations, where the rainfall is sufficient to support trees. These soils are very shallow, steep, stony, and infertile for the production of field crops. However, they serve a very useful purpose by supplying forest product such as timber and fuel.
  • Arid and Desert soils:-These  soils occur in western Rajasthan, Saurashtra, Kutchchh, western Haryana and southern Punjab . The soil is sandy to gravelly with poor organic matter, low humus contents, infrequent rainfall, low moisture and long drought season. The soils exhibit poorly developed horizons.
  • Saline and Alkaline soils :-These soils occur in areas having a little more rainfall than the areas of desert soils. They show white incrustation of salts of calcium & Magne sium and sodium on the surface. These are poor in drainage and are infertile.
  • Peaty and Marshy soils:-These are soils with large amount of organic matter and considerable amount of soluble salts. The most humid regions have this type of soil. They are black, heavy and highly acidic. They are deficient in potash and phosphate.

Soil erosion is described as the carrying away of soil. It is the removal of the soil by natural elements like water, wind, glacier and wave. Gravity tends to move soil down slope either very slowly as in soil creep or very rapidly as in landslides. The present shape of land has been carved through thousands of years.

Soil conservation is the preventing of soil loss from erosion or reduced fertility caused by over usage,Soil  acidification, salinization or other chemical soil contamination. Slash-and-burn and other unsustainable methods of subsistence farming are practiced in some lesser developed areas.

Natural Vegetation-Forest types and distribution, wild life, conservation, biosphere reserves

 

In India, at present forest areas cover about 76.5 million hectares of land, which is about 23 per cent of the total geographical area. It ranges from about 87 per cent in Andaman & Nicobar Islands to only about 4 percent in Haryana making to range difference of 83 percent. According to our National Forest Policy, 33% of the total geographical area of the country should be under the forest cover to maintain ecological balance. Unfortunately, it is below the norm outlined in our forest policy. The vegetation found in India can be divided into six main types. They are tropical evergreen forests, tropical deciduous forests, thorn forests, tidal forests and mountain forests.

Tropical Evergreen forests grow in the high rainfall areas of the Western Ghats, North –eastern India and the Andaman and Nicobar Islands. These forests grow in areas where the monsoon period lasts for several months.

Deciduous forests are found in regions with a moderate amount of seasonal rainfall that lasts for only a few months. Most of the forests in which Teak trees grow are of this type. The deciduous trees shed their leaves during the winter and hot summer months.

Dry tropical thorn forest occurs in areas of low rainfall. Forest types are saprophytic in nature. Trees are shorter than deciduous type. These forests mostly occur in the scanty rainfall region of Rajasthan, Punjab and Haryana. Most of the species are ‘acacia’ type.

Tidal Forests grow along the coast especially in the river deltas. These plants are uniquely adapted to be able to grow in a mix of saline and freshwater. They grow luxuriantly in muddy areas covered with silt that the rivers have brought down. The mangrove trees have breathing roots that emerge from the mud banks.

 

Conservation of Biodiversity and Wildlife

Biodiversity, or biological diversity, is the variety of all life forms.Sum total of all the variety of living organisms on earth constitute biodiversity. There are three levels of biodiversity:

  • genetic diversity—the variety of genetic information contained in individual plants, animals and micro-organisms
  • species diversity—the variety of species
  • ecosystem diversity—the variety of habitats, ecological communities and ecological processes.

Biodiversity is not static; it is constantly changing. It can be increased by genetic change and evolutionary processes, and it can be reduced by threats which lead to population decline and extinction.

Biodiversity is not uniformly distributed across the geographical regions of the earth. Certain regions of the world are very rich in biodiversity. We call such areas as “mega diversity zones”. We also refer to them as “hot-spots”. For example, India accounts for only 2.4 % of the land area of the world; but it contributes approximately 8% species to the global diversity due to existence of such pockets.

Humans depend for their sustenance, health, well being and cultural growth on nature. Biotic resources provide food, fruit, seed, fodder, medicines and a host of other goods and services. Importance of Biodiversity is due to:-

  • Food, fibre, medicines, fuel wood and ornamental plants
  • Protection of water resources
  • Soil protection
  • Breeding material for crop improvement
  • Nutrient storage and cycling
  • Pollution reduction
  • Climate stability
  • Maintenance of ecological processes

Causes of Loss of Biodiversity:-

  • Direct ways: Deforestation, hunting, poaching, commercial exploitation
  •  Indirect ways: Loss or modification of the natural habitats, introduction of exotic species, pollution, etc.
  •  Natural causes – Climate change.

International efforts for biodiversity conservation:-

  • Convention on Biological Diversity :-The objectives of the CBD are the conservation of biological diversity, the sustainable use of its components, and the fair and equitable sharing of the benefits arising from commercial and other utilization of genetic resources. The agreement covers all ecosystems, species, and genetic resources.
    CITES Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)
    The CITES aims to ensure that international trade in specimens of wild animals and plants does not threaten their survival. Through its three appendices, the Convention accords varying degrees of protection to more than 30,000 plant and animal species.
  • CMS Convention on the Conservation of Migratory Species of Wild Animals :-The CMS, or the Bonn Convention aims to conserve terrestrial, marine and avian migratory species throughout their range. Parties to the CMS work together to conserve migratory species and their habitats by providing strict protection for the most endangered migratory species, by concluding regional multilateral agreements for the conservation and management of specific species or categories of species, and by undertaking co-operative research and conservation activities.
  • International Treaty on Plant Genetic Resources for Food and Agriculture :-The objectives of the Treaty are the conservation and sustainable use of plant genetic resources for food and agriculture and the fair and equitable sharing of the benefits arising out of their use, in harmony with the Convention on Biological Diversity, for sustainable agriculture and food security. The Treaty covers all plant genetic resources for food and agriculture, while its Multilateral System of Access and Benefit-sharing covers a specific list of 64 crops and forages. The Treaty also includes provisions on Farmers’ Rights.
  • Ramsar Convention on Wetlands (popularly known as the Ramsar Convention) :-The Ramsar Convention provides the framework for national action and international cooperation for the conservation and wise use of wetlands and their resources. The convention covers all aspects of wetland conservation and wise use, recognizing wetlands as ecosystems that are extremely important for biodiversity conservation in general and for the well-being of human communities.
  • WHC World Heritage Convention (WHC) :-The primary mission of the WHC is to identify and conserve the world’s cultural and natural heritage, by drawing up a list of sites whose outstanding values should be preserved for all humanity and to ensure their protection through a closer co-operation among nations.
  • IPPC International Plant Protection Convention (IPPC) :-The IPPC aims to protect world plant resources, including cultivated and wild plants by preventing the introduction and spread of plant pests and promoting the appropriate measures for their control. The convention provides the mechanisms to develop the International Standards for Phytosanitary Measures (ISPMs), and to help countries to implement the ISPMs and the other obligations under the IPPC, by facilitating the national capacity development, national reporting and dispute settlement.
    The Secretariat of the IPPC is hosted by the Food and Agriculture Organization of the United Nations (FAO).

There are several strategies which are adapted for conservation of Biodiversity. Some of these are:

Legislation Formal policies and programmes for conservation and sustainable utilisation of biodiversity resources dates back to several decades. The concept of environmental protection is enshrined in the Indian constitution in articles 48a and 51a(g). Major central acts relevant to biodiversity include:
• Environment Protection Act, 1986
• Fisheries Act, 1897
• Forest Act, 1927
• Forest (Conservation) Act, 1980
• Wildlife (Protection) Act 1972 and Wildlife (Protection) Amendment Act 1991

In-situ Conservation Conserving the animals and plants in their natural habitats is known as in situ conservation. The established natural habitats are:
• National parks and sanctuaries
• Biosphere reserves
• Nature reserves
• Reserved and protected forests
• Preservation plots
• Reserved forests

Ex-situ Conservation like Boatanical and Zoological parks
Recording Indigenous Knowledge
Community Participation in Biodiversity Conservation

Food scarcity

 

According to FAO Food Security  is “a situation in which all people at all times have access to adequate quantities of safe and nutritious food to lead a healthy and active life”.

This definition requires three basic conditions to be met:

1) adequacy, i.e. supplies from domestic production, stocks and imports are sufficient to meet the nation’s needs,

2) availability i.e. stability of supply both spatially and temporally throughout the year and

3) access, i.e. the population has sufficient purchasing power to gain access to its food needs.

India is one of the few countries which have experimented with a broad spectrum of programmes for improving food security. It has already made substantial progress in terms of overcoming transient food insecurity by giving priority to self-sufficiency in foodgrains and through procurement and public distribution of foodgrains, employment programmes, etc. However, despite a significant reduction in the incidence of poverty chronic food insecurity persists in a large proportion of India’s population.

The range of adverse events, including reduced freshwater availability and more frequent extreme weather events, will considerably increase the risks for more efficient crop production and livestock management. Climate change is also likely to affect soil quality by depleting organic matter – a major contributor to soil fertility. In extreme cases, the degradation of the agricultural ecosystems could mean desertification, resulting in a total loss of the productive capacity of the land in question.

Food security is a multidimensional concept covering even the  micro level household food security,energy intakes and indicators of malnutrition.

Major components of food security are:-

  1. Production and Procurement
  2. Storage
  3. Distribution

Indian Agriculture is rightly called as a gamble with Monsoon, variability in food production and rising population creates food insecurity in the nation and worst effected are the downtrodden section of the society.

While India has seen impressive economic growth in recent years, the country still struggles with widespread poverty and hunger. India’s poor population amounts to more than 300 million people, with almost 30 percent of India’s rural population living in poverty. The good news is, poverty has been on the decline in recent years. According to official government of India estimates, poverty declined from 37.2% in 2004-05 to 29.8% in 2009-10.

Need for Self-Sufficiency:

India suffered two very severe droughts in 1965 and 1966. Food Aid to India was restricted to a monthly basis by USA under the P.L. 480 programme.  The Green Revolution made a significant change in the scene. India achieved self-sufficiency in food grains by the year 1976 through the implementation of the seed- water-fertilizer policy adopted by the Government of India.

Food grain production increased four-fold during 1950-51 and 2001-2002 from 51 million tons to 212 million tones. The country is no longer exposed to real famines. But the regional variation in the success of Green Revolution which was chiefly limited to northern- Western states has lead to the divide in the nation. Evergreen revoloution and Bringing green revolution to eastern India is the need of the hour.

Green revolution was focused on wheat and rice and thus the production of pulses was stagnant.

National Food Security Mission comprising rice, wheat and pulses to increase the production of rice by 10 million tons, wheat by 8 million tons and pulses by 2 million tons by the end of the Eleventh Plan (2011-12). The Mission is being continued during 12th Five Year Plan with new targets of additional production of food grains of 25 million tons of food grains comprising of 10 million tons rice, 8 million tons of wheat, 4 million tons of pulses and 3 million tons of coarse cereals by the end of 12th Five Year Plan.
The National Food Security Mission (NFSM) during the 12th Five Year Plan will have five components

(i) NFSM- Rice;

(ii) NFSM-Wheat;

(iii) NFSM-Pulses,

(iv) NFSM-Coarse cereals and

(v) NFSM-Commercial Crops.

Government through Public Distribution System has tried to counter the problem of food insecurity by providing the food grains through fair price shops.

The central Government through Food Corporation of India has assumed the responsibilities of  procurement,storage,transfer and bulk allocation of food grains to state governments.

The public distribution system (PDS) has played an important role in attaining higher levels of the household food security and completely eliminating the threats of famines from the face of the country, it will be in the fitness of things that its evolution, working and efficacy are examined in some details.

PDS was initiated as a deliberate social policy of the government with the objectives of:

  1. i) Providing foodgrains and other essential items to vulnerable sections of the society at resonable (subsidised) prices;
  2. ii) to have a moderating influence on the open market prices of cereals, the distribution of which constitutes a fairly big share of the total marketable surplus; and

iii) to attempt socialisation in the matter of distribution of essential commodities.

The focus of the Targeted Public Distribution System (TPDS) is on “poor in all areas” and TPDS involves issue of     35 Kg of food grains per family per month for the population Below Poverty Line (BPL) at specially subsidized prices. The TPDS requires the states to Formulate and implement :-

  1. foolproof arrangements for identification of poor,
  2. Effective delivery of food grains to Fair Price Shops (FPSs)

Its distribution in a transparent and accountable manner at the FPS level

Green Revolution and its impact on major crops of India

 

The Green Revolution was initiated in the 1960’s to address the issue of malnutrition in the developing world. The technology of the Green Revolution involved bio-engineered seeds that worked in conjunction with chemical fertilizers and heavy irrigation to increase crop yields.

Green Revolution was largely confined in wheat crop and in northern India such as Punjab, resulting in a limited contribution to overall economic development of the country. On the contrary, the agricultural growth in the 1980s (the second wave of the Green Revolution) involved almost all the crops including rice and covered the whole country, it enabled to raise rural income and alleviate rural poverty substantially. Such a rise of rural India as a “market‟ for non-agricultural products and services was an important pre-requisite for the rapid economic growth based on non-agricultural sectors‟ development in India after the 1990s.

Green Revolution is based on:-

(i) improved seeds of high yielding varieties,
(ii) adequate and assured supply of water for irrigation, and
(iii) increased and appropriate application of chemical fertilizers for increasing agricultural production.

India has failed to extend the concept of high-yield value seeds to all crops or all regions. In terms of crops, it remain largely confined to foodgrains only, not to all kinds of agricultural produce. In regional terms, only Punjab and Haryana states showed the best results of the Green Revolution. The eastern plains of the River Ganges in West Bengal state also showed reasonably good results. But results were less impressive in other parts of India. Those states which were originally rich derived the benefits of Green Revolution, e.g., Punjab, Haryana and Western U.P. As the benefits of new technology concentrated mainly in these areas, other Indian states could not match them.

Indian monsoon, mechanism, onset and retreat

 

The word “monsoon” comes from the Arabic word mausim, meaning season.Monsoons refer to a system of winds in the tropical regions under which the direction of winds is reversed completely between the summer and the winter seasons. Under this system, the winds blow from land to sea in winter and from sea to land in summer. Therefore, most of the rainfall in the regions influenced by the monsoons is received in the summer season while winter season is generally dry.

Due to a higher temperature over the land in summer, a low pressure area develops over the continents and the winds blow from neighbouring oceans towards the land. These winds are of maritime origin and hence cause ample rainfall in summer. On the other hand, the continents become colder than the neighboring oceans in winter. As a result a high pressure area is developed
over the continents. Therefore, winds blow from land to sea in winter. These winds, being of continental origin, are dry and do not cause rain.

Role of Jet streams, Tibet Plateau and atmosphere-ocean circulation is of prime importance for the origin of Indian Monsoon.During this summer season the vertical sun rays at tropic of cancer ,the circum polar whirl along with westerly jet stream weakened and shifted northward of the Himalayas and southern branch of this jet stream disappeared by 6-10 June. This removal of westerly jet stream to the north of Tibet plateau leads to reversal of curvature of flow of free air to the north and northwest of the subcontinent. It further leads to development of dynamic depression overlying the thermal depression already established at the surface of northwest Indian subcontinent which ultimately help to trigger the burst of Indian monsoon along with it vigorous advance over the Indian subcontinent.

As long as the position of upper air jet stream is maintained above the surface low pressure to the south of the Himalayas the dynamic anticyclonic conditions persist in the northwestern part of Indian subcontinent which obstruct the ascent of air from the surface low as the air is continuously descending from the above. This is the reason why the months of April, May and June are dry inspite of high temperature and evaporation while upper air low pressure in the east of the Himalayas over Myanmar, Assam and Bangladesh helps in ascend of air and produce rainfall.

During October and November, the high pressure over northern lndia, the winds start blowing from northeast as retreating monsoons. Clear skies and the increase in mercury northern plains is observed which is termed as ‘October heat’. At this time, the low pressure conditions shift to the Bay of Bengal giving rise to cyclonic depressions. These cyclonic depressions often results in the destruction of life and property generally on the eastern coast and the southern coast. Most of the rainfall of the Coromandel Coast is derived from depressions and cyclones.

Drainage Systems Himalayan and the Peninsular

 

Drainage: Flow of water through well-defined channels. Network of such channels is called a drainage system .

Drainage basin: An area drained by a river and its tributaries.

Watershed: Boundary line separating one drainage basin from other.

River basins are larger watersheds.

Drainage pattern of an area depends on the geological time period, nature and structure of rocks, topography, rocks, slope, amount of water and periodicity of flow.

Important drainage patterns:

  1. Dendritic: Resembling the branches of a tree. Eg. Northern Plain rivers
  2. Radial: Originate from a hill and flow in all directions. Eg. Rivers in Amarkantak
  3. Trellis: Primary tributaries parallel to each other and secondary tributaries join them at right angles.
  4. Centripetal: Rivers discharge waters from all directions in a lake or depression

A river drains the water collected from a specific area, which is called its catchment area.

Nearly 77 pc of drainage is towards the Bay of Bengal while about 23 pc is towards the Arabian Sea.

The Himalayan Drainage System

Mainly includes the Ganga, Indus and Brahmaputra river basins.

Over the plains, rivers of this system change the course often. River Kosi is also known as the ‘sorrow of Bihar’ due to flooding by its frequent change of course by deposition of sediments.

Evolution

Geologists believe that a mighty river called Shivalik or Indo-Brahma traversed the entire length of the Himalayas some 5-24 million years ago. Over time this got dismembered into the present three major river systems.

The Indus System

Indus river originates from a glacier near Bokhar Chu in Tibet in the Kailash Mountain range. Known as Singi Khamban (Lion’s mouth) in Tibet. It forms a spectacular gorge near Gilgit in J&K. Enters Pakistan near Chillar in the Dardistan region. Flows only through the Leh distt of J&K.

Smaller tributaries: Shyok, Gilgit, Zaskar, Nubra, Hunza, Shigar, Gasting, Dras. On right bank: Kabul river, Khurram, Tochi, Gomal, Viboa and hte Sangar.

Major tributaries: Satluj, Beas, Ravi, Chenab, Jhelum

Jhelum Origin: Verinag at foot of Pir Pinjal.

Flows through Srinagar and the Wular lake. Joins Chenab near Jhang in Pakistan

Chenab Origin: Two streams (Chandra and Bhaga) which join at Tandi near Keylong in HP.

Largest tributary of Indus. Aka Chandrabhaga. Flows for 1180 KM before entering Pakistan

Ravi Origin: Kullu hills of HP near Rohtang Pass. Enters Pakistan and joins Chenab near Sarai Sidhu
Beas Origin: Beas Kund near Rohtang pass.

Forms gorges at Kati and Largi in the Dhaoladhar range. Meets Satluj near Harike.

Satluj Origin: Rakas lake near Mansarowar in Tibet. Known as Langchen Khambab in Tibet.

Enters India at Ropar. Antecedent river. Bhakra Nangal Project is on this river.

 

The Ganga System

It is the largest river system in India.

Ganga rises in the Gangotri glacier near Gaumukh in the Uttarkashi district. Here it is known as the Bhagirathi. At Devprayag, Bhagirathi meets Alaknanda and is known as Ganga hereafter.

Panchprayag

Vishnu Ganga Joshimath

Dhauli and Vishnu Ganga meet to form Alaknanda

   
   
   
   

 

Alaknanda Origin: Satopanth glacier above Badrinath. Consists of Dhauli and Vishnu Ganga.
Yamuna Origin: Yamnotri glacier on Banderpunch range. Joins Ganga at Prayag (Allahabad).

RBT: Chambal, Sind, Betwa, Ken

LBT: Hindan, Rind, Sengar, Varuna.

Agra canal

Chambal Origin: Mhow in Malwa plateau.

Gandhi Sagar dam, Rana Pratap Sagar dam and Jawahar Sagar dam.

Famour for Chambal ravines.

Gandak Origin: In Nepal between Dhaulgiri and Mt. Everest. Enters Ganga plain in Champaran and joins Ganga at Sonpur near Patna.

Two streams: Kaliganfak and Trishulganga.

 

Ghaghra Origin: Glaciers of Mapchachungo

Tributaries: Tila, Seti and Beri

Deep gorge at Shishpani

Sarda (Kali) joint it and meet Ganga at Chhapra.

Kosi Origin: North of Mt. Everest in Tibet.

Tributaties: Son Kosi, Tamur Kosi, Arun

Changes course often. Sorrow of Bihar.

   

 

Ganga enters the plains at Haridwar.

Left Bank tributaries (LBT): Ramganga, Gomati, Ghaghara, Gandak, Kosi and Mahananda.

Right Bank tributaries (RBT): Son

Discharges into Bay of Bengal near Sagar island.

Structure, relief and physiographic divisions

 

Three Geological divisions:

  1. The peninsular block
  2. The Himalayas and other Peninsular Mountains
  3. Indo-Ganga-Brahmaputra Plain

 

  • Peninsualar block is made of gneisses (metamorphic) and granites (igneous).

Six physiographic divisions:

  1. The Northern and North-eastern Mountains
  2. The Northern Plain
  3. The Peninsular Plateau
  4. The Indian Desert
  5. The Coastal Plains
  6. The Islands

Northern and North-Eastern Mountains

Approximate length of the Great Himalayan range: 2500 KM. Width: 160-400 KM

Impact of Himalayas on the climate of India?

It can be divided into five sub-divisions:

  1. Kashmir (or Northwestern) Himalayas
  2. Himachal and Uttaranchal Himalayas
  3. Darjeeling and Sikkim Himalayas
  4. Arunachal Himalayas
  5. Eastern Hills and Mountains

Kashmir Himalayas

  • Ranges: Karakoram, Ladhakh, Zaskar, Pir Pinjal
  • Glaciers: Baltoro, Siachen
  • Passes: Zoji La (Great Himalayas), Banihal (Pir Pinjal), Photu La (Zaskar) and Khardung La (Ladakh)
  • Lakes: (freshwater) Dal and Wular; (saltwater) Pangong Tso and Tso Moriri
  • Pilgrimage: Vaishno Devi, Amarnath Cave, Charar-e-Sharif
  • They are also famous for Karewa formations which are useful for the cultivation of Zafran (a local variety of Saffron). Karewas are the thick deposits of glacial clay and other materials embedded with moraines.
  • Kashmir is located on the banks of Jhelum river.
  • Meanders is a typical feature associated with the rivers in this region.
  • In South, there are longitudinal valleys called duns; Jammu dun and Pathankot dun

 

Himachal and Uttarakhand Himalayas

  • Lies between rivers Ravi and Kali
  • Drained by two major river systems: Indus and Ganga
  • Northernmost part is an extension of the Ladakh desert, lies in Spiti.
  • Ranges: Great Himalayan Range, Lesser Himalayas (Dhaoladhar in HP and Nagtibha in Uttarakhand), Shivalik range
  • Pilgrimage: Gangotri, Yamunotri, Kedarnath, Badrinath, Hemkund Sahib and the five famous prayags (Refer to Panch Prayag)
  • Famous for hill stations: Dharamshala, Mussoorie, Shimla, Kaosani; Cantt.: Kasauli, Almora, Lansdowne, Ranikhet
  • The important distinguishing features of this area are the ‘Shivalik’ and ‘Dun formations’.
  • Important duns: Chandigarh-Kalka, Nalagarh, Dehra, Harike, Kota
  • Dehradun is the largest of all duns: Length – 35-45 KM, Width: 22-25 KM
  • Inhabited with the Bhotia They migrate to higher reaches (Bugyals) in summer and return to the valleys during winters.

 

Darjeeling and Sikkim Himalayas

  • Between Nepal Himalayas and Bhutan Himalayas.
  • Fast flowing rivers such as Tista
  • Peaks: Kanchenjunga
  • Tribe: Lepcha
  • Has a mixed population of Nepalis, Bengalis and tribals from Central India.
  • Importance: Due to the moderate slope, it is best suited for tea plantations. <India produces about 26 pc of tea in the world; second after China. Also, accounts for 12 pc of tea exports; fourth in the world.>
  • Duar formations are peculiar to this region.

 

Arunachal Himalayas

  • From Bhutan Himalayas to Diphu pass in the east.
  • Direction: Southwest to Northeast
  • Peaks: Kangtu and Namya Barwa
  • Rivers: Brahmaputra, Kameng, Subansiri, Dihang, Dibang and Lohit.
  • These rivers are perennial and have the highest hydro-electric power potential in the country.
  • Tribes: Monpa, Daffla, Abor, Mishmi, Nishi and Nagas
  • These communities practice shifting cultivation known as Jhumming.

 

Eastern Hills and Mountains

  • Direction: North to South
  • Ranges: Patkai Bum, Naga hills, Manipur hills, Mizo or Lushai hills
  • These are low hills
  • Tribes practice Jhum cultivation
  • Rivers: Barak. Most of the Nagaland rivers form a tributary of Brahmaputra. Rivers in eastern Manipur are the tributaries of Chindwin, which in turn is a tributary of the Irrawady of Myanmar.
  • Lake: Loktak
  • Loktak Lake: is an important lake in Manipur which is surrounded by mountains on all sides. It is the largest freshwater lake in northeastern India. Also called the only Floating Lake in the world due to floating masses of organic matter on it. It serves as a source for hydropower generation, irrigation and drinking water supply.
  • Keibul Kamjao National Park located in the Bishnupur district of Manipur is the only floating park in the world and is an integral part of the Loktak Lake. Home to the endangered Manipur Eld’s Deer or Brow-antlered Deer or Sangai or Dancing Deer.
  • Mizoram is also known as the ‘Molassis basin’ which is made up of soft unconsolidated deposits.

The Northern Plains

  • Formed by the alluvial deposits of rivers – Indus, Ganga and Brahmaputra.
  • Length: 3200 KM; Width: 150-300 KM

Three main zones:

  1. Bhabar
  2. Tarai
  3. Alluvial Plains (Khadar and Bangar)

Bhabar

  • Narrow belt. 8-10 KM wide.
  • Paralllel to Shivalik at the break-up of the slope. Hence, streams and rivers deposit heavy rocks (and at times disappear) in this zone.

Tarai

  • South of Bhabar. 10-20 KM wide.
  • Rivers re-emerge and create marshy and swampy conditions known as Tarai.

Alluvial Belt

  • South of Tarai.
  • Features of mature stage of fluvial erosional and depositional landforms such as sand bars, meanders, ox-bow lakes and braided channels. Riverine islands in Brahmaputra.
  • Brahmaputra takes a turn an almost 90 degree turn at Dhubri (Assam) before entering Bangladesh.

 

Peninsular Plateau

  • Bounded by the Delhi ridge, Rajmahal Hills, Gir range and Cardamom hills.
  • Made up of a series of patland plateaus: Hazaribagh, Palamu, Ranchi, Malwa, Coimbatore, Karnataka etc.
  • One of the oldest and most stable landmass of India.
  • Physiographic Features: Tors, block mountains, rift valleys, spurs, bare rocky structures, hummocky hills and quartzite dykes offering natural sites for water storage.
  • Black soil in western and northwestern parts.
  • Bhima fault in this region has frequent seismic activity (Lathur earthquake)
  • NW part also has ravines and gorges: Chambal, Bhind and Morena.

Three broad regions:

  1. Deccan Plateau
  2. Central Highlands
  3. Northwestern Plateau

Deccan Plateau

  • Bordered by Eastern Ghats, Satpura, Maikal range and Mahadeo hills
  • Important ranges: WG: Sahyadri, Nilgiri, Anaimalai and Caradamom hills; EG: Javadi hills, Palconda range, Nallamala Hills, Mahendragiri hills
  • EG and WG meet at Nilgiri hills.
  • Highest peak: Anaimudi (2695 m) on Anaimalai hills; Dodabetta (2637 m) on Nilgiri hills.
  • Rivers: Mahanadi, Godavari, Krishna, Kaveri etc.

Central Highlands

  • Bounded by the Aravali and Satpura range.
  • Relic mountains, highly denuded and form discontinuous ranges.
  • Near Jaisalmer it is covered by the longitudinal sand ridges and crescent-shaped sand dunes called barchans.
  • Elevation: 700-1000 m
  • Banas, a tributary of Chambal, originates in the Aravalli. Other tributaries of Yamuna originate from the Vindhyan and Kaimur ranges.
  • Minerals in Chotanagpur plateau.

 

Northeastern Plateau

  • Extension of the main Peninsular plateau.
  • Meghalaya and Karbi Anglong plateau.
  • Megahalaya plateau: Garo hills, Khasi hills and Jaintia hills (named after the tribals inhabiting the region)
  • Rich in minerals like coal, iron, sillimanite, limestone and uranium.
  • Receives maximum rainfall from SW monsoon. Hence, Meghalaya plateau has a highly eroded surface. Cherrapuni and Myswarnam.

 

Indian Desert

  • Aka Marusthali
  • Northwest of the Aravali hills
  • Dotted with longitudinal dunes and barchans.
  • Low rainfall: >150 mm per year Low vegetation cover
  • Evidence that this area was under the sea during the Mesozoic era.
  • Features: mushroom rocks, shifting dunes and oasis.
  • Rivers are ephemeral: Luni. Brackish lakes. Inland drainage.

 

Coastal Plains

Two divisions:

  1. Western coastal plains
  2. Eastern Coastal Plains

Western Coastal Plains

  • Submerged coastal plain. Hence, a narrow belt. Narrow in middle and broader towards north and south.
  • Ports: Provides natural conditions for the development of ports and harbours due to submergence. Kandla, Mazagaon (Mumbai), JLN port Navha Sheva, Maramagao, Mangalore, Cochin etc.
  • Mumbai has the world’s largest natural harbour.
  • May be divided into: Kachchh and Kathiawar coast in Gujarat, Konkan coast, Goan coast and Malabar coast.
  • Rivers don’t form delta.
  • Kayals (Backwaters): Found in the Malabar coast. Used for fishing and inland navigation. Every year Nehru Trophy Vallamkali (boat race) is held in Punnamada Kayal in Kerala.

 

Eastern Coastal Plains

  • Broader
  • Emergent coast. Hence, less number of ports and harbours. Chennai, Vizag, Paradwip, Haldia.
  • Delta formation

The Islands

Two major Divisions:

  1. Andaman and Nicobar
  2. Lakshwadeep & Minicoy

 

Andaman and Nicobar

  • Two major island groups: Ritchie’s archipelago and the Labrynth island.
  • The group is divided into: Andaman in the North and Nicobar in the South.
  • Andaman and Nicobar separated by the Ten Degree channel.
  • Barren Island
  • Peaks: Saddle Peak (N.Andaman – 738 m), Mt. Diavolo (Middle Andaman – 515 m), Mt. Koyob (S Andaman – 460 m) and Mt. Thuiller (Great Nicobar – 642 m)
  • Coral deposits found
  • Convectional rainfalls and equatorial type of vegetation.

Lakshadweep and Minicoy

  • Entire group built of coral deposits.
  • Total of 36 islands of which 11 are inhabited.
  • Smallest UT
  • Minicoy is the largest island
  • Separated by the 9 Degree Channel, north of which is the Amini Island and to the south Canannore island.
  • These islands have storm beaches consisting of unconsolidated pebbles, shingles, cobbles and boulders.

Structure, relief and physiographic divisions

 

Three Geological divisions:

  1. The peninsular block
  2. The Himalayas and other Peninsular Mountains
  3. Indo-Ganga-Brahmaputra Plain

 

  • Peninsualar block is made of gneisses (metamorphic) and granites (igneous).

Six physiographic divisions:

  1. The Northern and North-eastern Mountains
  2. The Northern Plain
  3. The Peninsular Plateau
  4. The Indian Desert
  5. The Coastal Plains
  6. The Islands

Northern and North-Eastern Mountains

Approximate length of the Great Himalayan range: 2500 KM. Width: 160-400 KM

Impact of Himalayas on the climate of India?

It can be divided into five sub-divisions:

  1. Kashmir (or Northwestern) Himalayas
  2. Himachal and Uttaranchal Himalayas
  3. Darjeeling and Sikkim Himalayas
  4. Arunachal Himalayas
  5. Eastern Hills and Mountains

Kashmir Himalayas

  • Ranges: Karakoram, Ladhakh, Zaskar, Pir Pinjal
  • Glaciers: Baltoro, Siachen
  • Passes: Zoji La (Great Himalayas), Banihal (Pir Pinjal), Photu La (Zaskar) and Khardung La (Ladakh)
  • Lakes: (freshwater) Dal and Wular; (saltwater) Pangong Tso and Tso Moriri
  • Pilgrimage: Vaishno Devi, Amarnath Cave, Charar-e-Sharif
  • They are also famous for Karewa formations which are useful for the cultivation of Zafran (a local variety of Saffron). Karewas are the thick deposits of glacial clay and other materials embedded with moraines.
  • Kashmir is located on the banks of Jhelum river.
  • Meanders is a typical feature associated with the rivers in this region.
  • In South, there are longitudinal valleys called duns; Jammu dun and Pathankot dun

 

Himachal and Uttarakhand Himalayas

  • Lies between rivers Ravi and Kali
  • Drained by two major river systems: Indus and Ganga
  • Northernmost part is an extension of the Ladakh desert, lies in Spiti.
  • Ranges: Great Himalayan Range, Lesser Himalayas (Dhaoladhar in HP and Nagtibha in Uttarakhand), Shivalik range
  • Pilgrimage: Gangotri, Yamunotri, Kedarnath, Badrinath, Hemkund Sahib and the five famous prayags (Refer to Panch Prayag)
  • Famous for hill stations: Dharamshala, Mussoorie, Shimla, Kaosani; Cantt.: Kasauli, Almora, Lansdowne, Ranikhet
  • The important distinguishing features of this area are the ‘Shivalik’ and ‘Dun formations’.
  • Important duns: Chandigarh-Kalka, Nalagarh, Dehra, Harike, Kota
  • Dehradun is the largest of all duns: Length – 35-45 KM, Width: 22-25 KM
  • Inhabited with the Bhotia They migrate to higher reaches (Bugyals) in summer and return to the valleys during winters.

 

Darjeeling and Sikkim Himalayas

  • Between Nepal Himalayas and Bhutan Himalayas.
  • Fast flowing rivers such as Tista
  • Peaks: Kanchenjunga
  • Tribe: Lepcha
  • Has a mixed population of Nepalis, Bengalis and tribals from Central India.
  • Importance: Due to the moderate slope, it is best suited for tea plantations. <India produces about 26 pc of tea in the world; second after China. Also, accounts for 12 pc of tea exports; fourth in the world.>
  • Duar formations are peculiar to this region.

 

Arunachal Himalayas

  • From Bhutan Himalayas to Diphu pass in the east.
  • Direction: Southwest to Northeast
  • Peaks: Kangtu and Namya Barwa
  • Rivers: Brahmaputra, Kameng, Subansiri, Dihang, Dibang and Lohit.
  • These rivers are perennial and have the highest hydro-electric power potential in the country.
  • Tribes: Monpa, Daffla, Abor, Mishmi, Nishi and Nagas
  • These communities practice shifting cultivation known as Jhumming.

 

Eastern Hills and Mountains

  • Direction: North to South
  • Ranges: Patkai Bum, Naga hills, Manipur hills, Mizo or Lushai hills
  • These are low hills
  • Tribes practice Jhum cultivation
  • Rivers: Barak. Most of the Nagaland rivers form a tributary of Brahmaputra. Rivers in eastern Manipur are the tributaries of Chindwin, which in turn is a tributary of the Irrawady of Myanmar.
  • Lake: Loktak
  • Loktak Lake: is an important lake in Manipur which is surrounded by mountains on all sides. It is the largest freshwater lake in northeastern India. Also called the only Floating Lake in the world due to floating masses of organic matter on it. It serves as a source for hydropower generation, irrigation and drinking water supply.
  • Keibul Kamjao National Park located in the Bishnupur district of Manipur is the only floating park in the world and is an integral part of the Loktak Lake. Home to the endangered Manipur Eld’s Deer or Brow-antlered Deer or Sangai or Dancing Deer.
  • Mizoram is also known as the ‘Molassis basin’ which is made up of soft unconsolidated deposits.

The Northern Plains

  • Formed by the alluvial deposits of rivers – Indus, Ganga and Brahmaputra.
  • Length: 3200 KM; Width: 150-300 KM

Three main zones:

  1. Bhabar
  2. Tarai
  3. Alluvial Plains (Khadar and Bangar)

Bhabar

  • Narrow belt. 8-10 KM wide.
  • Paralllel to Shivalik at the break-up of the slope. Hence, streams and rivers deposit heavy rocks (and at times disappear) in this zone.

Tarai

  • South of Bhabar. 10-20 KM wide.
  • Rivers re-emerge and create marshy and swampy conditions known as Tarai.

Alluvial Belt

  • South of Tarai.
  • Features of mature stage of fluvial erosional and depositional landforms such as sand bars, meanders, ox-bow lakes and braided channels. Riverine islands in Brahmaputra.
  • Brahmaputra takes a turn an almost 90 degree turn at Dhubri (Assam) before entering Bangladesh.

 

Peninsular Plateau

  • Bounded by the Delhi ridge, Rajmahal Hills, Gir range and Cardamom hills.
  • Made up of a series of patland plateaus: Hazaribagh, Palamu, Ranchi, Malwa, Coimbatore, Karnataka etc.
  • One of the oldest and most stable landmass of India.
  • Physiographic Features: Tors, block mountains, rift valleys, spurs, bare rocky structures, hummocky hills and quartzite dykes offering natural sites for water storage.
  • Black soil in western and northwestern parts.
  • Bhima fault in this region has frequent seismic activity (Lathur earthquake)
  • NW part also has ravines and gorges: Chambal, Bhind and Morena.

Three broad regions:

  1. Deccan Plateau
  2. Central Highlands
  3. Northwestern Plateau

Deccan Plateau

  • Bordered by Eastern Ghats, Satpura, Maikal range and Mahadeo hills
  • Important ranges: WG: Sahyadri, Nilgiri, Anaimalai and Caradamom hills; EG: Javadi hills, Palconda range, Nallamala Hills, Mahendragiri hills
  • EG and WG meet at Nilgiri hills.
  • Highest peak: Anaimudi (2695 m) on Anaimalai hills; Dodabetta (2637 m) on Nilgiri hills.
  • Rivers: Mahanadi, Godavari, Krishna, Kaveri etc.

Central Highlands

  • Bounded by the Aravali and Satpura range.
  • Relic mountains, highly denuded and form discontinuous ranges.
  • Near Jaisalmer it is covered by the longitudinal sand ridges and crescent-shaped sand dunes called barchans.
  • Elevation: 700-1000 m
  • Banas, a tributary of Chambal, originates in the Aravalli. Other tributaries of Yamuna originate from the Vindhyan and Kaimur ranges.
  • Minerals in Chotanagpur plateau.

 

Northeastern Plateau

  • Extension of the main Peninsular plateau.
  • Meghalaya and Karbi Anglong plateau.
  • Megahalaya plateau: Garo hills, Khasi hills and Jaintia hills (named after the tribals inhabiting the region)
  • Rich in minerals like coal, iron, sillimanite, limestone and uranium.
  • Receives maximum rainfall from SW monsoon. Hence, Meghalaya plateau has a highly eroded surface. Cherrapuni and Myswarnam.

 

Indian Desert

  • Aka Marusthali
  • Northwest of the Aravali hills
  • Dotted with longitudinal dunes and barchans.
  • Low rainfall: >150 mm per year Low vegetation cover
  • Evidence that this area was under the sea during the Mesozoic era.
  • Features: mushroom rocks, shifting dunes and oasis.
  • Rivers are ephemeral: Luni. Brackish lakes. Inland drainage.

 

Coastal Plains

Two divisions:

  1. Western coastal plains
  2. Eastern Coastal Plains

Western Coastal Plains

  • Submerged coastal plain. Hence, a narrow belt. Narrow in middle and broader towards north and south.
  • Ports: Provides natural conditions for the development of ports and harbours due to submergence. Kandla, Mazagaon (Mumbai), JLN port Navha Sheva, Maramagao, Mangalore, Cochin etc.
  • Mumbai has the world’s largest natural harbour.
  • May be divided into: Kachchh and Kathiawar coast in Gujarat, Konkan coast, Goan coast and Malabar coast.
  • Rivers don’t form delta.
  • Kayals (Backwaters): Found in the Malabar coast. Used for fishing and inland navigation. Every year Nehru Trophy Vallamkali (boat race) is held in Punnamada Kayal in Kerala.

 

Eastern Coastal Plains

  • Broader
  • Emergent coast. Hence, less number of ports and harbours. Chennai, Vizag, Paradwip, Haldia.
  • Delta formation

The Islands

Two major Divisions:

  1. Andaman and Nicobar
  2. Lakshwadeep & Minicoy

 

Andaman and Nicobar

  • Two major island groups: Ritchie’s archipelago and the Labrynth island.
  • The group is divided into: Andaman in the North and Nicobar in the South.
  • Andaman and Nicobar separated by the Ten Degree channel.
  • Barren Island
  • Peaks: Saddle Peak (N.Andaman – 738 m), Mt. Diavolo (Middle Andaman – 515 m), Mt. Koyob (S Andaman – 460 m) and Mt. Thuiller (Great Nicobar – 642 m)
  • Coral deposits found
  • Convectional rainfalls and equatorial type of vegetation.

Lakshadweep and Minicoy

  • Entire group built of coral deposits.
  • Total of 36 islands of which 11 are inhabited.
  • Smallest UT
  • Minicoy is the largest island
  • Separated by the 9 Degree Channel, north of which is the Amini Island and to the south Canannore island.
  • These islands have storm beaches consisting of unconsolidated pebbles, shingles, cobbles and boulders.