Land is an important component of natural resources. It is not evenly distributed all around the world. Differences are fuuudiu in its use and levels of development, all around the world, depending upon the factors like-relief, climate’and population distribution, etc. Their misuse can endanger survival of humanity.
1. Physical Features : Relief features like mountains, plateaus, river, slope of the land etc., influence forest cover, human habitation and hence put a limit on land use.
2. Types of Rocks : Types of rocks like sedimentary, igneous and metamorphic rocks, affect availability
of minerals and soils, etc., in an area. Soils are also made from weathering or breakdown of rocks. Therefore, rocks influence the type and degree of land use.
3. Slope : Humans have,generally preferred gentle slopes for habitation as well as agriculture. Steep slopes are not favourable for agriculture or construction of houses as such. Further, on steep slopes soil erosion occurs rapidly.
4. Climate : Climate is an important factor determining land use. It affects crop growth, habitation by animals and humans. Cold areas of Tundra region, or extremely hot and and climates of deserts are unsuitable for human habitation.
5. Human Needs : Human needs like construction of roads, railways, ,communication lines, land cultivation,
overcoming climate barriers, economic well-being and technology also determine land use. People inhabit
in less numbers in the snow bourrcvarea! of Siberia,’or deep inside the deserts, like Sahara.
6. Private vs. Community : Land can also be divided on the basis of Private land an ommunity land. Private land is owned by individuals whereas, community land is owned by the community. Tor common uses like collection of fodder, fruits, nuts, etc. It is also called common group resource.
Land Degradation
Land degradation takes place due to the following reasons:
1. Change in Landforms: Man has the ability to ground high hills or fill up deep depressions. Dams across rivers, mining and construction of houses, bridges and roads affect landforms directly.
2. Overgrazing : Overgrazing by domestic animals on a large scale has degraded the land, by removing
the vegetation. Overgrazing is the main cause of land degradation in states of Gujarat, Rajasthan,
Madhya Pradesh and Maharashtra. Overgrazing is the major cause of land degradation.
3. Degradation by Mining and Quarrying: More than 5,500 mines and quarries are operating in India.
The dumping of mineral wastes and abandoned mines are degrading and defacing the land.
4. Degradation by industrial vaste : Indiscriminate discharge of effluents has led to land degradation
and making the land unfit for cultivation.
5. Degradation by Industrial Dust: Fly ash from thermal power plants and dust generated by cement
1and ceramic industries have also led to land degradation.
How Can We Conserve Degraded Land
The following steps can go a long way in the conservation and reclamation of land :
1. Afforestation and control on overgrazing.
2. Plantation of shelter belts of plants.
3. Growing of thorny bushes to stabilise the sand dunes.
4. Proper discharge and disposal of industrial effluents and wastes.
5. Environmental friendly mining.
Soil is the base of terrestrial Iife supporting system. It is a fragile resource which can easily be damaged or destroyed by human activity. It must be conserved and treaeed with care.
Definition of Soil
According to Geologists, soil is 'the mixture of disintegrated rock material comprising mineral product together with decayed organic material. and living organisms'.
Factors Affecting Soil Formation
1. Weathering : Weathering is the bracking up of rocks and the agents of gradation carry this load over the large areas of the land. The colour, structure, mineral content in soil is formed due to it.
2. Climate : Without climate, weathering cannot take place. Climate has different effects on different types of rocks. Through temperature and precipitation, it affects rate of weathering, decomposition of organic material as well as the type and kind of vegetation in the area. Climate can be regarded as the most dominant factor in soil formation.
3. Biota or Biomass : The decomposition of organic matter gives humus and bacteria to do the activity of mixing and shifting of soil materials. The decayed matter also increases chemical action and lends colour and texture to soil.
4. Topography : It includes relief, slope as well as the direction with respect to sunshine and winds. Gentle slopes favour soil formation, while steep slopes lead to soil erosion.
Soil Erosion
Removal of soil by running water, winds and glaciers is called soil erosion. soil erosion is of various types:
1. Sheet Erosion : When a sheet or layer of soil is removed over a large area by running water, it is called sheet erosion.
2. Rill Erosion : If rills appear, they increase in number over a period of time. It is called rill erosion.
3. Gully Erosion : If the water flows regularly along a definite path down the slope, it cuts a channel
called gully and this type of erosion is called gully erosion. The land degraded by gully erosion is called badland or ravine.
How Can We Conserve Soil?
Chief types of soil conservation methods are as follows :
1. Afforestation : The humus in soil is a substance obtained from plant and animal remains. Therefore,
planting of trees, shrubs and grasses provides base for forming humus.
2. Farming Techniques : Soil conservation friendly farming techniques include – contour ploughing, strip cropping, terracing and other techniques. Strip cropping means, planting of alternate rows of different kinds of crops instead of leaving the land fallow. In Contour ploughing farmers plough across a slope along the line of the field in circular manner. In terracing, wide flat rows are made in step-like manner. The terraces hold rain water and prevent soil from getting washed down the slope. The other techniques include mulching, contour barriers, rock dam, intercropping and shelter belts.
Mulching : It is the covering of bare ground between plants, with a layer of organic matter like straw, to retain soil moisture.
Contour Barriers: It is the using of stone, grass, soil to build barriers along contours.
- In Rock Dam : Rocks are piled up to slow down flow of water. It prevents gullies and further soil erosion.
- In Intercropping : Different crops are grown in alternate rows and are sown at different times to protect the soil from rain wash.
- In Shelter Belts : Rows of trees are planted in coastal and dry regions, to check the wind movement and to protect soil cover.
Hydrological Cycle
The three atmospheric processes evaporation, condensation and precipitation, involved in the hydrological cycle cause water to be made available globally. For this reason, water is even called a renewable resource,
The distribution of water on Earth is as follows :
- Freshwater : The water made available on Earth by the operation of hydrological cycle is termed as fresh water. It accounts for just 1 percent of the total water available on Earth.
- Ice Caps : Total water made available on Earth, in the process of hydrological cycle is 2% of this.
- Water in Atmosphere : Only tiny fraction (0.001 per cent) of water is found in gaseous form (vapour) in atmosphere.
- Water in Oceans : 97 per cent of water is found in oceans, seas and salt water lakes. It covers about 71 per cent of Earth’s surface.
On planet Earth, water is found in all three gaseous, liquid and solid forms.
Do You Know?
97 Percent of all water is found in oceans, 2 percent is in the form of ice caps, glaciers and 1 percent
(fresh water) in lakes, river, etc.
Fresh Water
Since water came to be found on Earth, its total volume has remained the same. The quantity of water on1y change in its three states. For example, during the Ice Ages more water was found in solid state in the form of glaciers and ice caps. Fresh water, as we have seen above.
Distribution of Fresh Water
Like all other natural resources, water is also unevenly distributed over Earth. This distribution is generally governed by climate. Hence, the areas of more precipitation have surplus water, whereas the areas of deficit rainfall have water shortages.
As a result, world’s hottest deserts exist in this region. These hot deserts include Sahara and Arabian desert along with Sind, of which Thar in India is its eastern extension.
Recycling
Water is a renewable resource. Recycling of water, if done at the source of contamination, is the best way of removing impurities, according to needs
How Can We Conserve Water?
ª Efficient Use of Water : Efficient and economical use of water, specially to prevent wastage is the best way of conserving water.
ª Sprinkler Irrigation : In place of canals or irrigation through open channels sprinkler irrigation should be adopted in developing countries.
ª Recycling and Treatment of Effluents at its sources is also an ‘important method of conservation.
ª Water Harvesting : It involves artificial recharge of underground water by allowing rainwater to seep into the soil.
ª Vegetation Cover : Is essential forwater harvesting described above. It can also control the surface flow of rain water and soil erosion.
The only planet in our solar system where life exists is Earth. Life on Earth, is categorised into animal and plant kingdoms. The third type of living organisms is called bacteria. The organisms have overtime diversified into several different species. This diversity of species is called biodiversity.
Why do We Need to Protect Biodiversity?
The great distribution of animal and plant species known as biodiversity is quite essential for survival of life on Earth. Plants produce their own food and get energy from the Sun. When animals eat plants, energy is transferred from plants to plant-eating animals. The plant-eating animals may then be eaten by the flesh-eating animals including man: This way, energy travels from one organism to anothev, organism. This feeding transfer is known as food chain. It is imperative to protect this biodiversity in the ecosystem.
Ecosystems
Life is found in two types of ecosystems — marine and terrestrial.
Marine Ecosystem
Oceans occupy 71% of Earth’s surface. The marine ecosystems are larger than terrestrial ecosystems. Life emerged first in the oceans. It then got diversified into several species. Life in marine is also very complicated and is found even in the deepest parts of the oceans.
Terrestrial Ecosystem
On land, life is not easier as compared to oceans. There are three types of terrestrial ecosystem—Forests; Grasslands; and Semi-deserts and Deserts.
1. Forests
The vegetation of the world is divided on the basis of types of forests.
Chief Characteristics of Forest Ecosystem are:
1. The most productive parts of tress in forests are leaves. Leaves of green plants produce food through photosynthesis. The plant food contains sun’s energy, which travels to other species of life on land.
2. The forest is influenced by and adopted to particular physical conditions and climate.
3. Forests are home to animals and plants. This great variety of animals and trees in forests is called Biodiversity.
4. Forests are generally located where water supply is adequate with optimum temperature for tree growth.
Types of Forests
Forests can be divided into two main types : evergreen and deciduous.
(a) Evergreen Forests
These forests are called evergreen as their trees. do not shed their leaves. These are of two types — tropical rainforests and Coniferous forest. The tropical rainforests are located low altitude Souch East Asia in the subtropical region. Trees have broad leaves they grow tall to reach the sunlight. The coniferous forests on the other hand, are found in higher latitudes and higher altitude area of mountairls, like Himalayas and Andes. Both these ecosystems and are repositories of largest variety of plant and animal species.
(b) Deciduous Forests
The deciduous trees shed their leaves in a particular season. There is also a great variety of animals in. these forests. These forests provide habitat to a variety of plant and animals species. Human settlements are also found more around deciduous forests than the evergreen forests.
2. Grasslands
Grasslands are significant habitats of a great variety and a grate diversity of animal life. The grassland are located in main latitudinal zones-tropical and temperate.
3. Semi-Deserts and Deserts
There are two types of deserts : Semi-deserts and deserts. Both categories include hot and cold deserts.
(a) Semi-Deserts : These have thorny bushes and shrubs and are found in hot semi-deserts or semi-arid areas.
(b) Deserts : As mentioned earlier there are no absolute deserts.. Hot deserts like that of Sahara and Arabia and cold deserts like that of Gobi and Ladakh are characterised by plants of low growth and organisms living below the ground.
How Can We Conserve the Ecosystm?
Conservation
The government and the United Nations have passed laws against deforestation and killing of animals.
Laws have also been passed to control pollution. Biosphere reserves, national parks and wildlife sanctuaries have also been set up. All these efforts are still very inadequate. Human impact on natural environment is felt through a number of ways.
To prevent alternations and modifications of ecosystem, many-more, measures are needed. Otherwise, disturbances in balances would have serious consequences.
Do You Know?
Forests account for only 22% land, while the required land is 33% for survival of flora and founa and
mankind.
Earth's natural environment is different from the natural environment of other planets due to the presence, of forests and wildlife on it. One unique feature of the Earth is the structure and functioning of forest ecosystems, which is broadly uniform throughout the world.
Do You Know?
Biodiversity is the variety of flora and fanna found in an area. India has nearly 8 per cent of the total number of species, in the world. India is one of the 17 mega diverse countries which possess about 70 percent of the world's diversity.
Declining Wildlife
There was an abundance of wildlife in India before British established their rule here. With coming of the British rule and increase in the number of firearms, indiscriminate hunting. Due to the rise of population, there has been a demand for land, leading to a clash between wildlife and humans. The wildlife was the obvious loser and some wild animals even became extinct. Today 77 mammals, 21 reptiles, 40 species of birds and 3 amphibians are threatened with extinction. Tiger, lion, thamin of Manipur and hangul of Jammu and Kashmir, wildass of Kachchh, snow leopard, etc., are in the endangered list of wild animals.
Not only wild animals, but wild plants are also facing the threat of extinction. About 450 plant species are known to be endangered, threatened or rate.
Project Tiger
A country which boasted of more than 40,000 tigers, just a century ago, is today searching for tigers in its 29 tiger reserves. The first ever effort to save tigers was made by Mrs. Indira Gandhi by imposing a ban on tiger hunting in 1970.
Another step was the implementation of the Wildlife Protection Act in 1972. Afterwards the project Tiger was launched in 1973-74, with a Tiger Reserve covering 16,339 sq. km. of area, that has now been increased to 37,761 sq. km in 28 Tiger Reserves.
Initially the project Tiger yielded encouraging results. Till 1989, the Project Tiger was lauded as the most successful conservation effort in the world.
Why are Flora and Fauna Depleting?
In the past couple of centuries, flora and fauna are depleting due to following reasons :
1. Destruction of Habitats : Forests and grasslands are being destroyed by man’s activities and his expanding needs.
2. Rapidly rising Population : Expansion of agriculture, industrialisation as well as human habitation, has led to the depletion of vegetative cover.
3. Diseases and Pest : Cause like pollution, contact with exotic flora and, fauna, use of fertilizers and chemicals in agriculture, acid rain, damage to soil resources and changes in climate, have led to the decline of flora and fauna.
4. Depleting Food Resource : Most animals and even plants are facing extinction on account of depleting food resources.
Conservation of Flora and Fauna
The steps taken for the protection and preservation of our wildlife are the following :
1. Campaigns : The National Environment Awareness campaign is being organised every year under different categories to create awareness to save our forests and wildlife.
2. Blosphere Reserves : National parks and wildlife sanctuaries have been started to preserve the genetic diversity in representative ecosystems. The major aim of biosphere reserves are : (i) to conserve diversity of flora and fauna, (ii) to promote research on ecology and (iii) to provide facilities for education awareness and training.
3. Legislation : The Wildlife (protection) Act, 1972 and the Forest Conservation Act, 1980, have been enacted to protect forests.
4. Other Measures : Individual schemes like Project Tiger, Project Rhino, National Natural Resource Management System are also in operation or being undertaken from time to time.
Community and Conservation
Forests are considered only a collection oftrees-by people. But in reality, forest is a community of plants and trees, medicinal herbs and other life sustaining vegetation. Life of human race, animals and even insects is possible due to the vegetation. Planting of trees and their protection is encouraged by saying that, it is the greatest virtuous dew’ Some examples of observation by communities are :
1. Bishnois saved the trees some 275 years ago. Amrita Devi sacrificed her life to save the trees.
2. Van Panchayat and Pani Panchyats, of many villages of different states are regularly held for environmental protection.
1. Mention any two factors which influence land use.
2. What is land degradation?
3. What is deforestation?
4. Mention any two causes of land degradation.
5. How is soil formed?
6. How is soil erosion caused?
7. What is soil?
8. What is hydrological cycle?
9. How can we conserve water resources?
10. What is natural vegetation?
11. What was Rio de Janeiro Summit?
12. What are evergreen forests?
13. What are deciduous forests?
14. What are the three types of forest resources?
15. What are the endangered species of animals?
16. Wyatt is extinct species of animals?
17. What is land resource?
18. Name the factors that affect soil formation.
19. What is conservation? Describe its various methods? Describe any four causes of land degradation in India.
20. Name the two major ecosystems of the Earth.
21. Into which two kingdoms are all organisms divided?
22. Why are tall trees in forests regarded as representative of form of vegetation of a region?
23. How do humans affect other lifeforms?
24. Which are the two types of evergreen forests?
25. Name the different grassland ecosystems of the world.
26. What do you understand by Biodiversity?
27. Define food chain.
28. Describe the distribution of water resources.
29. How can we conserve forests?
30. What is Project Tiger?
31. Describe the causes of land degradation. How can we prevent it?
32. What are the various methods of conservation of soils.
33. Describe the chief characteristics of forest ecosystem.
34. Describe the process of water conservation.
35. Write an essay on conservation of forest.
36. Describe the steps taken for preservation of wildlife in India.
37. Afforestation and Deforestation.
38. Land Degradation and Land Conservation.
39. Tropical Evergreen forests and Deciduous forests
40. Flora, Forest and Vegetation.
41. Endangered and Extinct Species.
Important Questions with Answers
1. Which are the two main climatic factors responsible for soil formation?
2. Write any two reasons for land degradation today.
3. Why is land considered an important resource?
4. Name any two steps that government has taken to conserve plants and animals.
5. Suggest three ways to conserve water
Tick the correct answer
1. Which one of the following is NOT a factor of soil formation?
(a) Time
(b) Soil texture
(c) Organic matter
2. Which one of the following methods is most appropriate to check soil erosion on steep slopes?
(a) Shelter belts
(b) Mulching
(c) Terrace cultivation
3. Which one of the following is NOT in favour of the conservation of nature?
(a) switch off the bulb when not in use
(b) close the tap immediately after using
(c) dispose polypacks after shopping
1. Match the following
(A) Land use (p) prevent soil erosion
(B) Humus (q) land suitable for agriculture
(C) Rock dams (r) productive use of land
(D) Arable land (s) organic matter deposited on top soil
State whether the given statement is true
or false
1. Ganga-Brahmaputra plain of India is an overpopulated region.
2. Water availability per person in India is declining.
3. Rows of trees planted in the coastal areas to check the wind movement is called intercropping.
4. Human interference and changes of climate can maintain tfr6 ecosystem.
Important Questions with Answers
1. Two main climatic factors responsible for soil formation are temperature and rainfall.
2. Two reasons for land degradation are deforestation and overgrazing.
3. Land is considered as an important resource as it is used for different purpose like agriculture, forestry, mining, building homes, setting up industries, etc.
4. Two steps which government has taken to conserve plants and animals are:
(a) Project Tiger
(b) international convention sites lists several special species of animals and birds whose trade is prohibited.
5. Three ways to conserve water are:
(a) To link rivers through canals. (b)Not to use too much water while washing clothes, bathing, etc.
(c) Repair of dripping faucets by replacing washers.
Tick the correct answer
1. C 2. A 3. C
Match the following
(A) (r) (B) (s) (C) (p) (D) (q)
State whether the given statement is true or false
1. True 2. True 3. False 4. False