02 Natural Resources

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K L UNIVERSITYFRESHMAN ENGINEERING DEPARTMENT

Second Semester, 2010-11Environmental Studies

Natural Resources

1. Classification of Natural ResourcesOn the basis of origin, resources may be divided into:Biotic - Biotic resources are obtained from the biosphere, such as forests and their

products, animals, birds and their products, fish and other marine organisms. Mineral fuelssuch as coal and petroleum are also included in this category because they are formedfrom decayed organic matter.

Abiotic - Abiotic resources include non-living things. Examples include land, water, air andores such as gold, iron, copper, silver etc.

With respect to renewability, natural resources can be categorized as follows:Renewable resources are ones that can be replenished or reproduced easily. Some of

them, like sunlight, air, wind, etc., are continuously available and their quantity is notaffected by human consumption. Many renewable resources can be depleted by humanuse, but may also be replenished, thus maintaining a flow. Some of these, like agriculturalcrops, take a short time for renewal; others, like water, take a comparatively longer time,while still others, like forests, take even longer.

Non-renewable resources are formed over very long geological periods. Minerals andfossil fuels are included in this category. Since their rate of formation is extremely slow,they cannot be replenished once they get depleted. Of these, the metallic minerals can bere-used by recycling them. But coal and petroleum cannot be recycled.

On the basis of availability, natural resources can be categorised as follows:Inexhaustible natural resources - Those resources which are present in unlimited quantity

in nature and are not likely to be exhausted easily by human activity are inexhaustiblenatural resources (sunlight, air etc.)

Exhaustible natural resources - The amount of these resources are limited. They can beexhausted by human activity in the long run (coal, petroleum, natural gas, etc.)


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Forest Resources

2. Explain the Forest Uses / functions?Functions of the forests : Forests are of immense value to us. They are not only useful for

industry but also for rural economic growth. They offer huge potential for reducing povertywhile also conserving their valuable key resources.

Commercial Uses : Forests provide us a large number of commercial goods which includetimber, firewood, pulpwood, food items, gum, resins, non-edible oils, rubber, fibers,bamboo canes, fodder medicine, drugs and many more items.

Ecological Uses: Production Of Oxygen : The trees produce oxygen by photosynthesis which is so vital for

life on this earth .They are rightly called as EARTHS LUNGS. Reducing Global Warming : The main green house gas carbon dioxide is absorbed by the

forests as a raw material for photosynthesis. Thus forest canopy acts as a sink for carbondioxide there by reducing the problem of global warming caused by green house gascarbon dioxide.

Wildlife habitat : Forests are the homes of wild animals and plants. About 7 million species

are found in the tropical forests alone.Regulation of hydrological cycl e : Forested watersheds act like giant sponges, absorbingthe rain fall, slowing down the runoff and slowly releasing the water for recharge of springs.

About 50-80% of the moisture in the air above tropical forests comes from their transpiration which helps in bringing rains.

Soil c onservat ion : Forests bind the soil particles tightly in their roots and prevent soilerosion . They also act as wind-breaks .

Pollut ion Moderators : Forests can absorb many toxic gases and can help in keeping theair pure. They have also been reported to absorb noise and thus help in preventing air andnoise pollution.

3. Explain the Causes, effects and Control of Deforestation?

Forests have been known to possess huge potential for human use and they have beenexploited since early times for their vast potential .

Causes : Exploitation of forests has taken place to meet human demands in thefollowing ways:Shifting cultivation : There are an estimated 300 million people living as shifting cultivatorswho practice slash and burn agriculture and are supposed to clear more than 5 lakh ha of forests for shifting cultivation annually. In India, we have this practice in north east and tosome extent in Andhra pradesh ,Bihar and M.P which contribute to nearly half of the forestclearing annually.Fuel requirements : Increasing demands for fuel wood by the growing population in Indiaalone has shot up to 300-500 million tons in 2001 as compared to just 65 million tonsduring independence , thereby increasing the pressure on forests.Raw materials for industrial use : Wood for making boxes, furniture, railway-sleepers,

plywood, match-boxes , pulp for paper industry etc. have exerted tremendous pressure onforests. Plywood is in great demand for packing tea for Tea industry of Assam while fir treewood is exploited greatly for packing apples in J&K .Developmental projects : Massive destruction of forests occur for various developmentprojects like hydroelectric projects, big dams, road construction, mining etc .Growing food needs : In developing countries this is the main reason for deforestation. Tomeet the demands of rapidly growing population, agricultural lands and settlements arecreated permanently by clearing forests .Overgrazing : The poor in the tropics mainly rely on wood as a source of fuel leading toloss of tree cover and cleared lands are turned into grazing lands .

Some main causes of deforestation are:1. population explosion


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2. forest fires3. grazing animals4. pest attack5. natural calamities floods, storms, lightning damage forests6. mining and mineral processing7. dams and reservoirs8. irrigation canals9. military activities10. roads and railways

Effects of deforestation: It threatens the existence of many wildlife species due to destruction of their natural habitat

. Forest fires : These may be natural or man made , and cause huge forest loss Biodiversity is lost and along with that genetic diversity is eroded. Hydrological cycle gets affected , thereby influencing rainfall. Problems of soil erosion and loss of soil fertility increase.

In hilly areas it often leads to land slides. reduction in oxygen liberated by plants decrease in availability forest products loss of cultural diversity scarcity of fuel wood for people living near by forests lowering of water table due to more run off raise in CO 2 level resulting global warming, melting of ice and flooding of coastal areas

Control of Forest Degradation:More efficient agriculture on suitable farmland.Efficient forestry practice includes plantations.Reserves to protect species and ecosystems.

Using alternate source of energy instead of fuelwood , growing more trees (afforestation).Diverse species of natural forests must be protected as national parks and wildlifesanctuaries .Social Forestry : It is the planting of trees , mostly with the involvement of localcommunities , in unused and fallow lands , along roadside and railway tracks , aroundagricultural field and in degraded forest area .Agroforestry : It is a farming system that integrates crops and or livestock with trees andshrubs. This results in the multiple benefits along with diversified income sources .

Agroforestry is based on the principles of natural ecosystems.Local people play a big role in conservation of forests. Most forest managementprogrammes now involve local communities in planning, decision making andimplementation. They can become excellent guides in eco tourism ventures . Ex:- chipkomovement , JFM, NAP .

4. Explain the JFM activities?

Joint forest management (JFM) Under the JFM programme, the local communities and the government manage theresource and share the cost equally.An informal arrangement between local communities and the Forest Department began in1972, in Midnapore District of West Bengal.JFM has now evolved into a formal agreement which identifies and respects the localcommunitys rights and benefits that they need from forest resources.Local people will get economic benefit apart from conservation of forest habitats.


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Water Resources5. Explain the types and importance of water resources?

Water resources:It can be divided into two parts.a. Surface water b. Underground water.Surface water can be divided into rain water, river water , lake water and sea water.Under ground water can divided into spring and well water.

All aquatic eco-system are used by a large number of people for their daily needs.Water covers 70% of earths surface but only 3% of this is fresh water of this 2% is present

as polar ice caps only 1% is usable water in rivers lakes and subsoil aquifers. Ice caps andglaciers are about 77.2 % of fresh water and remaining 22.4 % is ground water and just0.4 % is distributed in lakes, swamps, rivers and streams.

From 1% of the available water, 70% of water is used up for agriculture, 25% industry and5% domestic use.

India uses 90% of its water for agriculture, 7% in industries and 3% domestic use.

In future, there is a great challenge facing the world in this century is the need to rethink theoverall management of resources.The world population has passed more than 7 billions in future there is a great problem for

water in 2000 years the world commission on dams studied indicate that a person needsminimum 20-40 litres of water per day.

6. What are the effects of ground water depletion?

1. Water logging & Salination2. Lowering of Water table3. Soil Erosion

7. Explain the effects of over- utilization and pollution of surface and ground water? With the growth of human population there is a increasing need for large amount of water

to fulfill a variety of basic needs . most of the people are using more water than they reallyneed .

Many agriculturist use more water than necessary to grow crops . There are many ways in which farmers can use less water without reducing yields such as

the use of drip irrigation systems. Agriculture also pollutes surface water and ground water stores by the excessive use of

chemical fertilizers and pesticidesConflicts over water Future global conflicts could arise over control of the shared river basins on which millions of

people depend for drinking water, irrigation and energy. There were many conflicts over the world on river water.

As much as 90 % of the waste water in the world is discharged with out treatment in thedeveloping countries.

Conflic ts over water around the world m ay be classified into the followin g categories.Military tool where water resources or water systems themselves are used by a nation or

state as a weapon during military action.

Political tool - where water resources or water systems themselves are used by a nation or state or a group for a political goal.

Terrorism where water resources or water systems themselves are either targets or toolsof violence by terrorists.


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Development disputes where water resources or water systems are a major source of contention and disputes in the context of economic and social development.

Some of the disputes are

Ganges Bhrahmaputra basin

India and Nepal wants to exploit the basins huge hydro electric power generating potential,where as Bangladesh wants water to be managed in such a way as to minimize floodingduring monsoon and water shortages during dry months.

Cauvery water dispute between Karnataka and Tamilnadu

Sutlej Yamuna canal between Haryana and Punjab.

8 Explain the Sustainable water Management methodsSave water campaign

Construction of several small reservoirs instead of larger onceDevelop small catchment dams and project wetlandsSoil Moisture conservation worksTreating and recycling municipal water for agricultural usePreventing leakages from Dams and canalsPreventing loss in Muncipal pipesEffective Rain water harvesting in Urban areasEffective water conservation measures in agriculture by using drip irrigationPricing water at its real value

9. Explain the Benefits of Construction of Dams

Water is precious resource that is becoming an increasingly scarce commodity world wide.To reduce scarcity, there is growing pressure to harness and utilize surface water sourceslike rivers by building dams over them for irrigation, hydro electricity, water transport etc.Multi-purpose dams account for a large proportion. Irrigation comes first in this categoryalso, followed by flood control, hydro power, domestic and industrial water supply andrecreation, with fish farming and navigation.

Various benefits of the dams are- hydro electric power generation- transfer of water using canals from excess to areas of deficit- irrigation- flood control and soil protection- ensuring year round water supply

- multipurpose river valley projects also provide for inland navigationMost of the single purpose dams around the world (48% approx.) are for irrigationand therefore it contributes greatly to food production and a considerable proportion (15%)of those dams serve for domestic and industrial water supply.

For the World as a whole, nearly 20% of dams generate electricity. However, inEurope alone, about 40% are hydro power dams.Other purposes include flood control (8%), recreation (4%) and to a lesser degree,inland navigation and fish farming.40% of world food production comes from irrigated farming, with a direct 16%contribution from land irrigated from dam reservoirs. 30-40% of the 268 millionhectares of irrigated land is watered from dams.Hydro-electric power produces 19% of world energy and is used in more than 150countries. It accounts for more than 90% of all energy in 24 countries and more than50% in 63 countries.


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12% of large dams supply towns and cities with water (60% in North America).13% of the world's dams help control river floods and flooding in nearly 75 countries.Some dams have helped improve ecosystems by creating new wetlands and newopportunities for fishing and recreation in the reservoirs.

10. Explain the effects of Construction of Dams (Both Upstream and Down stream)

Fragmentation and physiological transformation of riversImpact on Riverine ecosystemWater logging and salination of surrounding soilsLoss of Migratory routes for birds and animalsFishing and travel by boat distrupted.Emission of green house gases due to rotting vegetation and carbon inflowsSociological: Poorly managed involuntary displacement and loss of livelihoodMany of the displaced people were not recognized and therefore were not resettledor compensated

11. Explain the Socio economic effects of Construction of DamsPoorly managed involuntary displacement and loss of livelihoodMany of the displaced people were not recognized and therefore were not resettledor compensatedDepriving the indigenous people of the means to support traditional ways of life,particularly in case of culturally vulnerable indigenous/ethnic minority groups whichare largely dependent on locally available natural resources.Higher incidences of water borne diseases particularly among vulnerablecommunitiesLow Regional economic development reforms and inadequate distribution of projectbenefits to affected communities.It is not possible to mitigate many of the impacts of reservoir creation on terrestrial

ecosystems and biodiversity, and efforts to 'rescue' wildlife have met with little long-term successThe use of fish passes to mitigate the blockage of migratory fish has had littlesuccess, as the technology has often not been tailored to specific sites and speciesSome 40-80 million people have been physically displaced by dams worldwideMillions of people living downstream from dams (particularly those depending onnatural floodplain function and fisheries) have also suffered serious harm to their livelihoods and the future productivity of their resources has been put at riskWhere compensation was provided it was often inadequate, and where the physicallydisplaced were enumerated, many were not included in resettlement programmes.Those who were resettled rarely had their livelihoods restored, as resettlementprogrammes have focused on physical relocation rather than the economic andsocial development of the displacedThe larger the magnitude of displacement, the less likely it is that the livelihoods of affected communities can be restored


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Mineral Resources

12. Environmental effects of extracting mineral resourcesMining

Mining is extraction of economic minerals and building materials from the earth. Thesematerials may be extracted by adopting opencast mining or underground mining. Generallymost of the mines are located in forest areas. In opencast mining it requires removal of huge quantity of unwanted material along with useful minerals. Mining activity requiresdiversion of forest land for various activities. Forest land is diverted for

- opening of mine and extraction of material- dumping of unwanted waste material- road to be formed for transportation of men and materials.- Big mines require residential accommodation for employees and providing basic amenities

Effects of Mining

DeforestationAir, water, Soil, Noise pollutionsLoss of forest cover Loss of biodiversitySoil erosionWater loggingGround water depletionAppropriation of the land belonging to the local communities,Impacts on health,Alteration of social relationships,Destruction of forms of community subsistence and life,Social disintegration,

Radical and abrupt changes in regional culturesDisplacement of other present and/or future local economic activities


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Food Resources

13. Changes caused by agriculture and overgrazingEffects of Overgrazing: Soil Erosion, Land degradation, Loss of Useful species

Effects of Agriculture:a. Traditional Agriculture: Forest clearing, Soil erosion and depletion of nutrientsb. Modern Agriculture: Impacts related to high yielding varieties, Fertilizer related impacts,

pesticide related impacts, water logging, Salinity

i. Fertilizer related impacts: Micro nutrient imbalance, Nitrate Pollution, Eutrophicationii. Pesticide related impacts: Pest resistant problems, Biomagnification, Non target species

death

14. Effects of modern agriculture1. High yielding variety (HYV) seeds Loss of genetic diversity2. Effect of Chemical Fertilizers By nitrate pollution Blue baby syndrome, by enrichment of

nitrates and phosphates into the lakes and ponds - Eutrophication3. Effect of Chemical pesticides Bioaccumulation of toxic elements into the plants andBiomagnification in various species and effects to the human health

4. Killing of Non target Organisms: The pesticide impact will be more on birds which willdepend on insects and pests present in agriculture.

5. The over irrigation leads to loss of ground water, energy, soil erosion.

16. Effects of Fertilizers and pesticidesi. Fertilizer related impacts: Micro nutrient imbalance, Nitrate Pollution, Eutrophicationii. Pesticide related impacts: Pest resistant problems, Biomagnification, Non target species

death

17. Brief notes on Waterlogging and salinity Waterlogging: Presence of water in an area over a period of time is called water logging.

The main cause is due to the over usage of ground water leads to decrease of soil porosityand results lack of water penetration into the subsurface. The rain water will not rechargeand stagnant at the top soil. The excessive usage of (agricultural) irrigation will also leadsto Waterlogging condition. Due to this, excess water in the plant root zone restricts theaeration required for optimum plant growth. It may affect the availability of several nutrientsby changing the environment around the roots.

Salinity: Accumulation of salts in the topsoil due to Waterlogging condition and effects theplant growth is called Salinity. The salts in the subsoil will mix with water and reached tothe top layers. When water completely evaporates, the salts will remain in the top soil andcauses salinity.

Excess salts in the root zone inhibit water uptake by plants, affect nutrient uptake and mayresult in toxicities due to individual salts in the soil solution. Excess exchangeable sodiumin the soil may destroy the soil structure to a point where water penetration and aeration of the roots become impossible. Sodium is also toxic to many plants.

Waterlogging and salinity in the soil profile are most often the result of high water tablesresulting from inadequate drainage or poor quality irrigation water. Adequate surfacedrainage allows excess irrigation and rain water to be evacuated before excess soilsaturation occurs or before the water is added to the water table. Adequate subsurfacedrainage insures that water tables are maintained at a sufficient depth below the soilsurface to prevent waterlogging and salt accumulation in the root zone.


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Salinization of the soil profile is prevented because upward capillary movement of water andsalts from the water table does not reach the root zone. Adequate subsurface drainagealso allows salts to be removed from the soil profile through the application of excessirrigation water (leaching).

Energy Resources

18. Classification of Energy resources with examplesSources of energy can be described as renewable and non-renewable.Renewable sources are those which are being continually replenished. Eg: Solar, wind,

hydroelectric, geothermal, Biogas, biomass, nuclear, tidal etcNon-renewable energy source s: The resources which are available in limited amount and

develop over longer period of time. (being used faster than it can be replaced) Eg. Coal,Natural oils and Natural gas.

19. Advantages and disadvantages of Renewable and non renewable energy sources

20. Brief notes on A. Solar, B. Wind, C. Hydro electrical and D. Biomass energySolar EnergySolar energy is the most readily available and free source of energy since prehistoric times.

It is estimated that solar energy equivalent to over 15,000 times the world's annualcommercial energy consumption reaches the earth every year. Worlds largest Solar Plantis located at California. India receives solar energy in the region of 5 to 7 kWh/m2 for 300to 330 days in a year. This energy is sufficient to set up 20 MW solar power plant per square kilometer land area. Solar energy is renewable because the sun is always present.Japanese farmers are substituting P.V.Operated insect killers for toxic pesticides which willharmful to environment and also human being.

Applications of solar energy:1. Solar water heaters, 2. Solar lights, 3. Solar Cookers 4. Solar vehicles 5. Solar home

appliances 6. Solar power plant 7. Solar furnace


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Advantages Solar energy is free - no fuel, no waste or pollution . In sunny countries, easy to use in remote places Good for low-power uses such as solar powered garden lights and battery chargers

Disadvantages Doesn't work at night. Very expensive to build solar power stations. Can be unreliable unless you're in a very sunny place

21. Role of an individual to conserve energy sources Domestic Sector:Turn off lights, fans and other appliances when not in useUse the sunlight for drying the cloths instead of using power driersConstruction of buildings with large ventilators and windowsTake shorter showers. Heating water uses energy.Keep rooms cool by closing the blinds, shades, or curtains.

Use compact fluorescent bulbs.

Industrial Sector:Change of Raw material, process and technologyRecycling, Reduction, Reuse and Regeneration methodsEffective usage of power by using renewable energy resourcesConditioning all types of working process

Agricultural Sector:Usage of Drip irrigationUsage of Solar lights in the fieldsUsage of PV insect killers in place of pesticides

Effective usage of agricultural waste material

Transportation Sector:Less usage of petrol and diesel vehiclesUsage of Bicycle in place of bikesUsage of electronic bikes and other vehiclesUsage of mass transportationStopping vehicles near signalsServicing the vehicles regularly

Land ResourcesLand is a major constituent of the lithosphere and is the source of materials essential to manand other organismsIndias geographical area is 328 million hectares.

Increase in population has put great pressure on land resources and this has led to- destruction of forest land for agricultural and other purposes- urbanization- industrialization- infrastructure (roads, railways and transmission lines)


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22. Causes, effects and control of a. Land degradation b. Soil erosion c.Desertification.

Land degradation:Causes: 1.Natural factors: Heavy rains, High speed winds, Natural Disasters, Expansion of

Desert2.Anthropogenic factors: Mining, Urbanisation, Deforestation, Overgazing, Construction of

Dams and Canals, Excessive use of fertilizers, Dumping of industrial and municipal wasteSoil Erosion:Causes: Large-scale deforestation, Floods in rivers, Overgrazing by cattle, Dry violent

winds, Improper agriculture techniques.Effects: Decrease in the productivity of land, Desertification of land, Deposition of soil in

water bodies, Reduction of agricultural land at the banks of riversControl: Afforestation on barren land, Control of overgrazing, Construction of small check

dams, Promoting equitable use of water resources, preventing excavation of rocksDesertification: Desert is an area of land that receives very less or no rainfall. It is very

thinly populated with little or no vegetation. The fertility in deserts is minimum and they aredevoid of wildlife. Conservation of fertile non desertic land into infertile desertic land is

called desertification.Causes: Natural factors: Very low rainfall, Excessive evaporation, vast difference in diurnaltemperature extremes, High salinity of soils

Anthropogenic factors: Continuous cutting of trees, overgrazing, over-irrigation, Excessiveploughing, conservation of pastures to arable lands, excessive use of fertilizers

Effects: Rapid soil erosion, Poor soil quality, Unfavourable climate, Low water table, saltyand hard water, increase of economic and human costs.

Control: Promoting large scale plantation of trees, changing agricultural practices andpromoting dryland farming (Economically viable, ecologically sustainable and sociallyacceptable) Development of water catchment areas


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23. Role of an individual in conservation of natural resources.

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02 Natural Resources