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UNIT-3: NATURAL RESOURCES: RENEWABLE AND NON-RENEWABLE RESOURCES 2 Marks Questions with answers: 1. What are natural resources? Natural resources refer to the things that exist freely in the nature for human use and don’t need action of mankind for their generation or production. 2....

UNIT-3: NATURAL RESOURCES: RENEWABLE AND NON-RENEWABLE RESOURCES 2 Marks Questions with answers: 1. What are natural resources? Natural resources refer to the things that exist freely in the nature for human use and don’t need action of mankind for their generation or production. 2. What are the types of natural resources? a) Renewable and Non-renewable resources b) Biotic and Abiotic natural resources c) Stock natural resources 3. What is renewable resources? Renewable resources are the ones that are consistently available regardless of their use. They can be fairly recovered or replaced after utilization. Eg: Water, Air. 4. What are non-renewable resources? Non-renewable resources are the ones that cannot be substituted or recovered once they have been utilized or destroyed. Eg: Fossil fuels. 5. What are biotic natural resources? Biotic natural resources are the ones that come from the ecosphere (organic and living organisms). Eg: Animals, Forests. 6. What is abiotic natural resources? The abiotic natural resources are the ones that come from non-organic and non- living materials. Eg: Water, Land, and Air. 7. What are stock natural resources? Stock natural resources are those that are present in the environment and need technology for their utilization. Eg: Hydrogen. 8. What is fallow land? The land which is not utilized for cultivation for last 3 to 5 years is considered as fallow land. 9. What is land degradation? Land degradation is the decline in land quality or reduction in its productivity. 10. What is strip farming? It is a practice in which cultivated crops are sown in alternative strips to prevent water movement. 11. What is crop rotation? It is one of the agricultural practice in which different crops are grown in same area following a rotation system. 12. What is contour farming? This type of farming is usually practiced across the hill side and is useful in collecting and diverting the run off to avoid erosion. 13. What is soil erosion? Soil erosion is the removal or displacement of part of soil or the whole soil by ocean currents, wind or water. 14. What is desertification? Desertification is defined as the process of land degradation in arid, semi-arid and sub- humid areas due to various factors including climatic variations and human activities. 15. What is deforestation? Deforestation is the process of clearing forest cover by cutting down, burning and damaging plantation. 16. State any 2 causes of deforestation. a) Urbanization b) Agricultural activities 17. What is forest? Forest is large area of land covered thick vegetation with huge trees or other woody trees consisting a variety of species of plants and animals. 18. What are the types of forests? a) Tropical rain forest b) Temperate deciduous forest c) Temperate coniferous forest d) Taiga forest 19. What is ground water? Ground water is fresh water located in the subsurface pore space of soil and rocks. 20. What is desalination? Desalination is an artificial process by which saline water (sea water) is converted into fresh water. 21. What is flood? A flood is an overflow of water on land which is usually dry. It is caused by a volume of water within a body of water, such as lakes, overflowing. 22. What is drought? A drought is a prolonged shortage in the water supply, surface water or ground water. It can last for months or years, or may be declared after as few as 15 days. 23. What are the types of energy resources? a) Non-conventional or renewable energy b) Conventional or non-renewable energy 24. What is Non-conventional or renewable energy? It is a type of non-replenish able or non-exhaustible form obtained from the natural environment. Eg: Solar energy, wing energy, Tidal energy. 25. What is solar energy? Solar power is the technology of obtaining usable energy from the light of the sun. 26. What is hydroelectric power? Hydroelectric power is the energy derived from the flowing water in rivers or from man- made installations where water flows from a high reservoir down through a tunnel. 27. What is geothermal energy? It is the heat from deep within the earth’s interior can rise up to the surface. 28. What are Conventional or non-renewable energy? Non-renewable energy resources are those that cannot be replenished in a short period of time. Eg: Coal, Oil, Natural gas, Petroleum 29. What is natural gas? Natural gas is a gaseous fossil fuel consisting of methane, the shortest and lightest hydrocarbon molecule. 5 Marks Questions with Answers: 1. Write a note on classification of natural resources. Types of natural resources are as follows: 1. Renewable and Non-renewable resources:  Renewable natural resources: Renewable resources are the ones that are consistently available regardless of their use. Eg: Sun, water and wind  Non-renewable natural resources: Non-renewable resources are the ones that cannot be recovered once they have been utilized or destroyed. Eg: Fossil fuels, minerals.  2. Biotic and Abiotic natural resources:  Biotic natural resources: The biotic natural resources are the ones that come from ecosphere. These include resources such as plants, animals, and other materials. 3. Stock natural resources: Stock natural resources are that are present in the environment and need technology for their utilization. Eg: Hydrogen 2. What are the types of land use in India? The Types of Land Use in India are: 1. Forests area 2. Land not available for cultivation 3. Cultivable wasteland 4. Fallow land 5. Net area sown 1. Forest area According to National Forest Policy 1952, the reporting area of the forest must be 33.3% of the total land. The proportion of the forest area is not evenly distributed in the country. Madhya Pradesh, Arunachal Pradesh, Odisha, Maharashtra, Andhra Pradesh, Andaman Nicobar Islands are reporting more area under forest. 2. Land not available for cultivation: The land used for human settlements, transport routes, canals, quarries, the mountains, deserts, marshes etc. are coming under this category. It accounts 12.11% of total land in India. 3. Cultivable land: This category includes permanent pasture and other grazing area, land under miscellaneous tree, crops, groves and cultivable waste. This category covers about 8.6 % of the country’s total reporting land. The permanent pasture and other grazing are being reported high in the states of Rajasthan, Himachal Pradesh and Madhya Pradesh. But it is less in Manipur, Dadar and Nagar Haveli, Goa and Andaman and Nicobar Islands. 4. Fallow lands The land which is not utilized for cultivation for last 3 to 5 years is considered as fallow land. It may be cultivated. It accounts for about 8.13 % of the India’s total land. 5. Net area sown India has a net sown area of 46.2% of the total reporting land in India. There has been a phenomenal increase in the net area sown during the last five decades. 3. Explain the causes of land degradation. Causes of Land Degradation:  Deforestation: Deforestation is taking place at a faster rate due to increasing demands of timber, fuel and forest products which results into degradation of land resources.  Overgrazing: Overgrazing refers to excessive eating of grasses and other green plants by cattle.  Agricultural practices: The modern agricultural practices, excessive use of fertilizers and pesticides has adversely degraded the natural quality and fertility of the cultivation land.  Industrialization: Development of industries for the economic growth of the country leads to excessive deforestation and utilization of land in such as way that it has lost its natural up gradation quality.  Urbanization: Increasing growth of population and demand for more residential areas and commercial sectors is also one of the reasons for land degradation.  Fertilizers and pesticides  Damage to top soil. 4. Explain the control measures for land degradation? Following are some practices for controlling land degradation: 1. Strip farming: It is & practice in which cultivated crops are sown in alternative strips to prevent water movement. 2. Crop Rotation: It is one of the agricultural practice in which different crops are grown in same area following a rotation system which helps in replenishment of the soil. 3. Ridge and Furrow Formation: Soil erosion is one of the factors responsible for lad degradation. It can be prevented by formation of ridge and furrow during irrigation which lessens run off. 4. Construction of Dams: This usually checks or reduces the velocity of run off so that soil support vegetation. 5. Contour Farming: This type of farming is usually practiced across the hill side and is useful in collecting and diverting the run off to avoid erosion. 5. What are the causes of soil erosion? Explain. Causes of Soil Erosion are 1. Wind When strong winds blow, the topsoil along with the organic matter is carried away by the wind. This happens more often when the land is not covered with grass or plants. Such conditions are very common in desert and semi-desert regions where strong winds blow very frequently.  2. Water When it rains in the hilly areas, the soil gets washed away towards the plains. The running water deposits the mineral-rich soil in the riverbed and over the years this deposition of soil can change the course of the river. 3. Overgrazing When cattle are allowed to graze on the same field repeatedly, all the available grass, including the roots are eaten by them. 4. Deforestation Humans have taken land from the forest to cultivate in order to feed the ever- increasing population and to build houses, industries, etc. Cutting down trees on a large scale for these purposes is deforestation. 6. What are the causes of desertification? The causes of desertification are:  Water shortage: The deficit of water resources for crops and other vegetation affects their normal growth and eventually destabilizes other ecological processes.  Deforestation: Desertification is one of the leading human causes of desertification.  Overgrazing: Excessive grazing by domestic animals increases the loss of vegetation and reduces the soil’s ability to hold moisture.  Over population: A rapid increase in human population demands higher amounts of natural resources and leads to desertification.  Climate change: withy significantly reduced rainfall. Drought occurs and leads to hotter and drier climate and causes desertification.  Unsustainable agriculture techniques: Improper irrigation method used will also leads to desertification. 7. Explain the preventive measures for desertification. 1. Afforestation and planting of trees 2. Crop rotation and mixed cropping 3. Improving vegetation 4. Mulching: The process of covering the open surface of the ground by a layer of some external material 5. Improved method of drainage. 8. Explain the causes of deforestation. The causes of deforestation are:  Logging Illegal logging activities are very common that destroy the livelihoods of the people depending on forests. Wood-based industries like paper, match-sticks, furniture need a substantial amount of wood supply.   Agricultural Activities The conversion of forests into agricultural land is a big reason for deforestation. Due to overgrowing demand for food products, many trees are chopped down for crops and for cattle grazing.  Mining Oil and mining of coal require a large amount of forest land. Construction of roads leads to deforestation as they provide the way to remote land.  Urbanization As the population grows, the needs of people increases which further leads to deforestation. Forests shrink to a great extent to meet the requirements like for construction of roads, development of houses, mineral exploitation and expansion of industries.  Timber Production One of the primary cause of deforestation is the production of timber. There is a lot of demand for timber and so deforestation increases.  Forest Fires We lose a large number of trees each year due to fires in the forest in various portions worldwide. This happens due to extreme summers and winters. The fire caused, by man or nature, results in huge loss of forest cover. 9. Explain the benefits of dams. Advantages of Dams  Electricity is produced at a constant rate with the help of hydroelectricity or hydroelectric power.  Dams are constructed to control floods.  Dams improves human life quality by improving drinking water and to support economic growth.  The lake or reservoir which forms behind the dam can also be used for irrigation purposes, water sports or even as other forms of pleasurable activities.  When used, the electricity produced by the dams does not even generate greenhouse gases and therefore they do not pollute the atmosphere. 10. Explain the problems of Dams. Disadvantages of dams are:  Building a dam is very expensive, and the government needs to ensure that strict guidelines are followed and a very high standard is maintained.  They must operate for many years in order to become profitable enough to compensate for the high building cost.  People residing in villages and towns in the nearby area, where there are chances of flooding, have to be relocated.  Sometimes people are removed forcibly to set up hydro-power plants and it poses a serious ethical concern.  The building of large dams can cause serious changes to the earth’s surface and  lead to geological damage. It can trigger frequent earthquakes, however, modern planning and design of dams have reduced the possibility of occurrence of certain disasters.  Dams break occurs from heavy rainfall  Dams changes the pattern of the flow of river.  Dams have effect on downstream fisheries as they obstruct the movement of migratory fishes. 11. Explain the types of floods. Various types of flood are as follows:  Coastal Flooding Extreme weather and high tides can cause a rise in sea levels, sometimes resulting in coastal flooding.  River Flooding River flooding is one of the most common types of inland flood; occurring when a body of water exceeds its capacity. Flooding can cause considerable damage to surrounding properties, as well as posing a significant safety threat.  Flash Flooding Caused by heavy and sudden rainfall, flash flooding happens when the ground cannot absorb the water as quickly as it falls. This type of flood usually subsides quickly, but while it lasts can be fast-moving and dangerous.  Groundwater Flood As opposed to flash floods, groundwater flooding takes time to occur. As rain falls over an extended period, the ground becomes saturated with water until it cannot absorb any more. When this happens, water rises above the ground’s surface and causes flooding. This type of flooding can last for weeks or sometimes even months.  Drain and Sewer Flooding Sewer floods are not always attributed to the weather. As well as rainfall, they could occur as a result of a blockage or similar failure within the drainage system. Drain and sewer flooding may be internal (within a building) or external. 12. What are the causes of Drought? Explain. i. Rainfall deficiency When a region goes for long periods without any rain, more than a season then the situation leads to drought. ii. Human causes Human acts such as deforestation, construction, and agriculture negatively impact water cycle. iii. Drying out of surface water In extremely hot seasons or because of certain human activities surface water may dry out resulting drought. iv. Global warming Global warming situation leads to drought conditions as the average temperature of earth’s surface keeps on increasing.  v. Deforestation Deforestation and other poor land-use practices, like intensive farming, continue to diminish soil quality and reduce the land’s ability to absorb and retain water. 13. Explain the effects of drought. A. Environmental impacts on drought. i. Drying out of water bodies ii. Reduction of soil quality iii. Unsuitable conditions for plant and vegetation survival iv. Migration and even death of animals and wildlife B. Economic impacts of drought i. Increased budgetary spending by farmers for irrigation purpose ii. Reduced crop yields iii. Industrial and government losses iv. Higher energy cost for economies dependent on hydro-power C. Social impacts on droughts i. Outbreak of water borne diseases ii. Hunger, anemia, malnutrition and death iii. Migration of people and anxiety. 14. Briefly explain the types of energy resources. Energy resources are of two types. 1. Non-conventional or renewable energy 2. Conventional or non-renewable energy 1. Non-conventional or renewable energy. It is a type of non-replenish able or non-exhaustible form of energy in environment. i. Solar energy Solar power is the technology of obtaining usable energy from the light of the sun. ii. Wind energy The kinetic energy of wind can satisfy several times the energy demand of the country. iii. Hydroelectric power Hydroelectric power is the energy derived from the flowing water or from man-made installations where water flows from a high reservoir down through a tunnel. iv. Biomass energy Biomass is organic matter produced by plants and animals both terrestrial and aquatic and their derivatives.is v. Geothermal energy In geological suitable areas, heat from deep within the earth’s interior can rise up to the surface. Such heat is referred as geothermal energy.  vi. Tidal power Tide means periodical natural rise and fall of water of the ocean and is produced by the interaction of the gravitational fields of the Earth-Moon- Sun system vii. Hydrogen Hydrogen gas is an important alternative energy source to conventional fuels. 2. Conventional or Non-Renewable energy: i. Coal Coal is a fossil fuel formed from plant remains that have been compacted, hardened, chemically, altered by heat and pressure over time. ii. Petroleum/crude oil Petroleum or crude oil is a naturally occurring liquid form in formations in the earth consisting of a complex mixture of hydrocarbons of various lengths. iii. Nuclear energy Through the process of nuclear fission or nuclear fusion, matter is converted into energy. iv. Natural gas Natural gas is a gaseous fossil fuel consisting of methane, the shortest and highest hydrocarbon molecule.