CBSE Class 8 Geography Chapter 2 Land, Soil, Water, Natural Vegetation and Wildlife Resources – Detailed explanation of the chapter ‘Land, Soil, Water, Natural Vegetation and Wildlife Resources’ along with question answers. Given here is the complete explanation of the lesson, along with all the exercises, Question and Answers given at the back of the lesson.
Class 8 Geography Chapter 2 – Land, Soil, Water, Natural Vegetation and Wildlife Resources
Introduction
The people who stay in different parts of the world lead different lives according to the place’s climate and land variety. Varied regions have differences in the quality of water, soil, land, animals, technology usage and natural vegetation. A place may differ from another one on the basis of availability of such resources.
Land, Soil, Water, Natural Vegetation and Wildlife Resources Class 8 Video Explanation
Land
It is one of the most important natural resources that we need for our survival. About 30 percent of the total area of the surface of our planet is occupied by the land. Still, not all part of the land is worth building habitats.
Due to different characteristics of climate and land, there is uneven population distribution in different regions of the world. The regions which usually consist of steep slopes of mountains, thick forest regions, low lying areas that are prone to water-logging, rugged topographies and desert areas usually consist of less population or are unoccupied.
River valley and plains are some of the most densely populated regions across the globe where agriculture is the most suitable occupation.
Land Use
People depend on the land for different usages such as mining, building roads and houses, forestry, setting up factories, agriculture among others. This process is known as ‘Land Use.’
The usage of land is determined by different factors such as water availability, topography, climate, minerals, soil. Different human factors like pollution and technology are also few of the important determinants of patterns of land usage. The arrangement of artificial and natural physical features of a particular region can be defined as Topography.
On the basis of land ownership, further the land is classified into two types:
- Community Land: The whole community owns and maintains this type of land for common usages such as collection of medical herbs or nuts, fodder or fruits and vegetables. Another name for this type of land is Common Property Resources.
- Private Land: Individuals own these types of land.
As the population has increased, people and their various demands from the land have gone up, but the land is available in a limited amount. The land quality is also different at various places. Many times common lands have been encroached in order to build housing complexes and shopping centers. Similarly, in rural areas forests are being cleared to make space for practicing agriculture.
In the last few years, there has been a change in the ways people utilize land for different purposes. It represents the cultural change that has occurred in various areas over time. Soil erosion, desertification, degradation of land, landslides are some of the major reasons which have resulted as environmental threats. Construction and agricultural activities are responsible for these issues.
Conservation of Land Resource
As the population growth has sky-rocketed, the different demands of people have also increased. Due to this, the destruction of arable land and forest cover has started occurring on a large scale. This has also led to the fear of losing these natural resources. Therefore, the government needs to introduce laws in order to keep a check on the process of land degradation. Regulated use of fertilizers and chemical pesticides, land reclamation, introducing measures to control overgrazing and afforestation are some of the measures to conserve land resources.
Soil
Soil is a thin layer of a powdered substance that covers earth’s surface. It is linked closely with the land. The type of soil is determined by different land forms. Weathered rocks, minerals and organic matter that is found on the earth are responsible for formation of soil. This process takes place due to weathering. The soil becomes fertile if it is made up of the right mix of organic matter as well as minerals. You will be surprised to know that just to form one centimeter of soil, it takes hundreds of years.
The lowermost layer of the soil is called Parent rock. Above this layer lies weathered rock material. The second layer is known as Subsoil which consists of silt, clay and sand. The top layer of the soil is the one which is visible to our eyes and it consists of vegetation and humus.
Factors of Soil Formation
The climate factors and nature of parent rock is mainly responsible for the formation of soil. Few of the other factors are organic material’s role, topography of the place and time required for the composition of soil formation. All these factors may occur in different ways at different places.
Those factors which affect the formation of soil are:
- Parent Rock: It is responsible for determining chemical properties, permeability, colour, mineral content and texture.
- Flora, Fauna and Microorganism: It is responsible for affecting humus formation rate.
- Time: It determines how thick the soil profile would be.
- Relief: Slope and altitude are responsible for determining how the soil would get accumulated.
- Climate: The climatic factors such as rainfall and temperature are responsible for influencing formation of humus and weathering rate.
Degradation of Soil and Measures of Conservation
Soil erosion and its depletion are few of the major reasons that pose a threat to soil in the form of a natural resource. Few of the factors which are responsible for soil erosion are rain wash, overgrazing, pesticides or chemical fertilizers overuse, floods and deforestation.
Few of the methods that can be used to conserve the soil are as follows:
1. Mulching: A type of organic matter layer such as straw is used to cover bare grounds present between plants. It is a useful way to retain the moisture of the soil.
2. Rock Dam: In order to slow down the flow of water, we can pile up rocks at a place. It is helpful in preventing gullies which further strengthens the soil of that place.
3. Contour Barriers: Soil, stones and grass can be utilized to build up barriers on the side of counters.In the front of barriers, trenches are constructed so that water could be collected.
4. Shelter Belts: People residing in dry and coastal regions plant trees in rows so that wind movement could be checked and controlled in order to protect the soil cover.
5. Terrace farming: Terraces or Broad Flats are constructed on slopes that are steep in nature. In this way, people are able to grow different kinds of crops on flat surfaces. This prevents soil erosion as well as running off of surfaces.
6. Intercropping: Alternate rows are constructed in order to grow different types of crops. To protect the soil from washing away, crops are sown in different seasons.
7. Contour Ploughing: Ploughing of different crops are carried out in parallel to the slopes of the hill. It becomes a natural barrier for water so that water does not flow down.
Water
It is a necessary renewable resource. Water covers almost three-fourth of the earth’s surface. Hence, our planet is also addressed as a ‘water planet.’ Around 3.5 billion years back, life began for the first time in the waters of the primitive oceans. Oceans occupy more than two thirds of the earth’s surface. It supports various forms of plant and animal lives which are rich in variety. However, the waters of oceans can’t be utilized for regular consumption since they are saline in nature. Fresh water occupies more than 2.7 percent of the total available amount of water which is really low. Out of this, approximately 70 percent of water is available in the form of ice sheets and glaciers in Greenland, Antarctica and other mountainous regions. These sources are inaccessible due to their location. Due to this, humans can use only 1 percent of available fresh water. They are found as surface water in the form of lakes and rivers, as ground waters and water vapour present in the earth’s atmosphere.
Currently, the most precious substance on the surface of the earth is freshwater. You cannot add or subtract water from the earth’s surface. Its total volume will always be constant. As the water is in constant motion, it keeps cycling from one ocean to another, air, river, lakes and land via different processes such as run-off, precipitation and evaporation. The whole process is referred to as ‘Water Cycle.’
Water in huge amounts is utilized by human beings for processes such as washing, drinking and production. Other similar usage include water being utilized for generation of electricity in dams and reservoirs, industries, agriculture among others. Increase in population, increase in urbanisation and prices of food, people’s rising living standards are some of the other reasons which has caused shortages of water supply. It has also led to water sources drying up and getting severely polluted.
Problems of Water Availability
Many places in the world are facing water shortages today. Majority of Asia, Australia, Africa, Mexico, western USA and various South American countries are facing this issue. Those countries which are situated in climatic zones that face scarcity of water are majorly affected. Due to variations in annual or seasonal precipitation, water shortages are occurring at a rapid rate.Countries located in climatic zones most susceptible to droughts face great problems of water scarcity. Apart from that water sources are being over-exploited and contaminated on a large scale as well.
Conservation of Water Resources
The world is facing a major problem as access to adequate and clean water has almost become impossible. The government is taking various steps to conserve sources of water. Although water is a renewable resource, still pollution and overuse is making it unfit for use. Discharge of untreated sewage, chemical wastes and wastes from factories are few of the major sources of water pollution. Due to these, water becomes contaminated with hazardous chemicals such as pesticides, metals and nitrates.
These chemicals are non-biodegradable in nature and can enter the body of humans via water. In order to control water pollution, the effluents present in it need to be treated before they are released into water bodies.
Vegetation cover and forests are capable of slowing the runoff of surface and replenishing the water present underground. To prevent surface run-off, another good method is water harvesting. Those canals which are used to irrigate fields need to be linked in a proper manner in order to minimise losses caused due to seepage of water. In order to check water losses caused due to seepage, one could opt for water sprinkling in the fields. It also reduces water loss caused by irrigation.
Those regions which are dry or have high rates of evaporation, one can use triple or drip irrigation. One can save an enormous amount of water by using these methods.
Natural Vegetation and Wildlife
Biosphere is a region that lies in a narrow zone of contact between the atmosphere, lithosphere and hydrosphere. You can find natural vegetation and wildlife only in the biosphere.In this zone, all living beings are interdependent and interrelated on each other in order to survive.
This system of life supporting each other is known as the ecosystem. Wildlife along with vegetation are valuable and useful resources. From plants, you get oxygen for breathing, timber, shelter for those animals living in the wild, the plants strengthens the soil so that different crops could be produced, underground water can be stored, functions in form of shelter belts, provides us with fruits, vegetables, latex, medicinal herbs, turpentine oil, etc. There exists several other important usages of plants as well.
Insects, animals, birds along with aquatic living beings fall under Wildlife. From them we get hides, milk, wool and meat. Insects such as bees help in flowers’ pollination, produce honey and act as decomposers in the ecosystem. Vultures are capable of feeding on dead organisms.They are an example of scavengers. They are one of the important cleansers of the environment. All animals irrespective of their size are important in maintaining balance in this ecosystem.
Distribution of Natural Vegetation
The growth of vegetation in a region is interdependent on moisture and temperature. The vegetation types found across the globe are grouped into scrubs, forests, tundra and grasslands. Those areas which face heavy rainfall, there huge trees get a chance to thrive. The forests are associated with areas that have water supply in abundance. In an area, if the amount of moisture decreases, density and size of trees found there also decrease.
Grasses and short stunted trees can be found in those regions which have moderate rainfall – they are the grassland regions. Scrubs and thorny shrubs can be found growing in dry areas that have low rainfall. Plants of these regions have deep roots and their leaves have thorny and waxy surfaces which in turn prevents moisture during the process of transpiration. Cold polar regions have tundra vegetation that have lichens and mosses.
In the current era, we have more population residing on the earth than it was three centuries back. In order to feed these large sections of people, authorities have been forced to clear vast amounts of forest lands so that crops can be grown. Due to this, forest cover has started disappearing. Forests are a valuable resource that needs to be conserved.
Conservation of Natural Vegetation and Wildlife
Forests are an example of wealth provided to us by nature. Plants are responsible for providing shelter to animals found in the wild. Together, they are responsible for maintaining the ecosystem. Interferences by humans in various forms and climatic change have resulted in animals and plants losing their natural habitats – i.e. forests. Several species have become endangered or vulnerable. Many of them are on the verge of becoming extinct as well.
Some of the major reasons due to which the forest resources are being depleted are:
- Forest fire
- Deforestation
- Landslides
- soil erosion
- tsunami
- constructional works
Another big concern is poaching. When the wild animals are hunted in an illegal manner, it is known as Poaching. Due to this, many wildlife species are going extinct. The animals found in the wild are poached on a major scale in order to collect feathers, nails, horns, skins, hides and fur. Examples of such poached animals are elephant, tiger, black buck, snow leopard, black bucks, rhinos, peacocks, vultures, ostriches and lions. We can protect these species by taking appropriate measures.
Biosphere reserves, National parks and wildlife centuries have been introduced in order to protect wildlife and natural vegetation. It is important to conserve wetlands, creeks and lakes in order to save such resources from depletion.
If we do not disturb the species of wildlife, there will always remain a balance in wildlife. Habitats belonging to wildlife have been disturbed on a large scale due to activities of humans. Several animals and birds and animals have gone extinct or are on this verge due to indiscriminate killings being carried out.
At community and regional level, the authorities should encourage programs like Vanmahotsav and Social Forestry. School children must be introduced to the concept of bird watching. They should visit forest camps to know about habitats of wildlife beings.
Many countries have made laws against killing of animals and birds as well as their trading. Killing of animals such as peacocks, lions, deers, great Indian bustards and tigers is illegal in our country.
The Convention on International Trade in Endangered Species (CITES) of Wild Fauna and Flora has been established. It contains a list of several species of birds and animals whose trade is banned. It is the ethical duty of every person on this planet to conserve our natural resources.
Questions and Answers
- Answer the following questions.
i) Which are the two main climatic factors responsible for soil formation?
Answer: The two main climatic factors responsible for soil formation are:
- Rainfall
- Temperature
ii) Write any two reasons for land degradation today.
Answer: These reasons are:
- Overuse of chemical fertilizers
- deforestation
iii) Why is land considered an important resource?
Answer: We humans use land for different usages such as building roads and houses, cultivating agriculture, mining, setting up of industries, forestry among others. That’s why land is considered an important natural resource.
iv) Name any two steps that the government has taken to conserve plants and animals.
Answer: Steps taken by the government to conserve plants and animals:
- The government organizes awareness programs such as Vanmahotsav and social forestry.
- In order to preserve the habitat of wildlife beings, the government has established biosphere reserves, wildlife sanctuaries and national parks
v) Suggest three ways to conserve water.
Answer: Three ways to conserve water are as follows:
- Canals should be lined properly to avoid wastage of water
- For irrigation, farmers should be taught to use the water sprinkler system.
- Rainwater harvesting methods should be introduced.
Tick the correct answer.
(i) Which one of the following is NOT a factor of soil formation?
(a) time (b) soil texture (c) organic matter
Answer: (b) soil texture
(ii) Which one of the following methods is most appropriate to check soil erosion on steep slopes?
(a) shelterbelts (b) mulching (c) terrace cultivation
Answer: (c) terrace cultivation
(iii) 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
Answer: (c) dispose polypacks after shopping
- Match the following:
i. Land use |
(a) prevent soil erosion |
ii. humus |
(b) narrow zone of contact between the lithosphere, hydrosphere and atmosphere |
iii. Rock dams |
(c) productive use of land |
iv. biosphere |
(d) organic matter deposited on top soil |
Answer.
i. Land use |
(c) productive use of land |
ii. humus |
(d) organic matter deposited on top soil |
iii. Rock dams |
(a) prevent soil erosion |
iv. biosphere |
(b) narrow zone of contact between the lithosphere, hydrosphere and atmosphere |
4. State whether the given statement is true or false. If true, write the reasons.
(i) Ganga–Brahmaputra plain of India is an overpopulated region.
(ii) Water availability per person in India is declining.
(iii) Rows of trees planted in the coastal areas to check the wind movement is called intercropping.
(iv) Human interference and changes of climate can maintain the ecosystem.
Answers:
(i) True. This region consists of fertile land where agriculture is easy. Hence, it is overpopulated.
(ii) True. As the population has increased at a rapid rate, different factors such as needs of people, urbanisation, rise in demand of food and changing lifestyle has caused shortage of water.
(iii) False. This process is known as Shelter Belt.
(iv) False. This process has resulted in loss of habitat of wildlife and their extinction on a massive scale.