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RESOURCES MODULE 3

Natural resources

Meaning

•Natural resources are naturally occurring substances that are considered valuable in their relatively unmodified (natural) form. A natural resource's value rests in the amount of the material available and the demand for it. The latter is determined by its usefulness to production.
A commodity is generally considered a natural resource when the primary activities associated with it are extraction and purification, as opposed to creation. Thus, mining, petroleum extraction, fishing, hunting, and forestry are generally considered natural-resource industries (natural resources include its minerals, energy, land, water, and biota )

Characteristics of resources
Resources have three main characteristics:
•utility,
•quantity (often in terms of availability), and
•use in producing other resources.

Types of resources

On the basis of origin, resources may be divided into:

•Biotic - Biotic resources are the ones which are obtained from the biosphere. Forests and their products, animals, birds and their products, fish and other marine organisms are important examples. Minerals such as coal and petroleum are also included in this category because they were formed from decayed organic matter.

•Abiotic - Abiotic resources comprise of non-living things. Examples include land, water, air and minerals such as gold, iron, copper, silver etc.

On the basis of the stage of development, natural resources may be called

Potential Resources - Potential resources are those which exist in a region and may be used in the future. For example, mineral oil may exist in many parts of India having sedimentary rocks but till the time it is actually drilled out and put into use, it remains a potential resource.

Actual Resources -are those which have been surveyed, their quantity and quality determined and are being used in present times. For example, the petroleum and the natural gas which is obtained from the Bombay High Fields. The development of an actual resource, such as wood processing depends upon the technology available and the cost involved. That part of the actual resource which can be developed profitably with available technology is called a reserve.

On the basis of renew ability, natural resources can be categorized into:
•Renewable Resources - Renewable resources are the ones which can be replenished or reproduced easily. Some of them, like sunlight, air, wind, etc., are continuously available and their quantity is not affected by human consumption. Many renewable resources can be depleted by human use, but may also be replenished, thus maintaining a flow. Some of these, like agricultural crops, 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 - Non-renewable resources are formed over very long geological periods. Minerals and fossils are included in this category. Since their rate of formation is extremely slow, they cannot be replenished once they get depleted. Out of these, the metallic minerals can be re-used by recycling them. But coal and petroleum cannot be recycled

Natural Resources Accounting

Natural Resources Accounting - accounting for the state and quality of the environment and the natural resource base by bringing the environment into national accounting through deductions from the gross domestic product for various aspects of environmental degradation such as the value of pollution abatement and control expenditure, the value of environmental damage during the accounting period and the depletion of natural resources

Exploitation of natural resources
•Exploitation of natural resources is an essential condition of the human existence.
•This refers primarily to food production, but minerals, timber, and a whole raft of other entities from the natural environment also have been extracted.
•Often the exploitation of nature has been done in a non-sustainable way, which is causing increasing concern, as a non-sustainable exploitation of natural resources ultimately threatens human existence Over-exploitation in some cases lead to exhaustion, particularly by excessive forestry, fishing and hunting. This over-exploitation may be explained in part by human overpopulation in some areas of the planet, ever-increasing world demand for these resources and the development of international trade.

Examples of over exploitation
•Industrial-scale logging, for wood products and timber, destroys or fragments millions of acres of forests each year, along with the habitat they provide to many uniquely adapted species.
•Over-harvesting of fisheries has driven several fish species to the brink of extinction and reduced the overall diversity of marine life.
•Over-hunting and illegal trade in endangered species are a prime threat to their survival. This occurs even in the well-developed countries such as the US. For example, box turtles in the US are illegally collected and exported as pets, and, they die in the tens of thousands each year. These species are very slow to reproduce, and, in some populations, poaching has resulted in too few hatchlings surviving to offset adult mortality
• Over Extraction of minerals from mining.

Soil Degradation

•Soil degradation occurs where our activities (either directly or indirectly) cause it to become less vigorous or less healthy. The ultimate degradation is the removal or loss of its physical components.Acidification, salinity, organic depletion, compaction, nutrient depletion, chemical contamination, landslides, and erosion are all forms of soil degradation that can be brought about by inappropriate land use practices.

A soil can degrade in 3 ways:
•Physical, chemical or biological run-down causing a reduction in vigor. This can result from excessive product removal (depleting soil nutrients), reduction in plant growth, lowered organic cycling, increasing soil temperatures, leaching, compaction and surface crusting.
•Reduction in mass and volume through erosion. This reduces the physical size of the soil ecosystem.
•Accumulation of specific soil chemicals to levels that detrimentally effect plant growth. Such materials include: soluble salts (causing salinity); hydrogen ions (causing acidification); and, some chemicals from industrial, mining and agricultural activities (chemical contamination

Forms of Soil Degradation
•Sheet and Rill Erosion -Rain drops and surface flows causing shallow stripping of soil.
•Gully Erosion- Concentrated flows of water scouring along flow routes causing sharp sided entrenched channels deeper than 0.5 m.
•Wind Erosion- Where wind has direct access to bare dry soil and causes soil detachment and removal. Fine material can be transported long distances. Coarser material moves only locally by bouncing and rolling.
• Land Slips -Where sloping soils become unstable and slip downhill. Usually brought about by increase in soil mass because of excess moisture in the soil. Can also result from construction activities.
• Acidification- Where the acid level of soil progressively increases and interferes with plant growth. Associated with nitrate leaching, product removal and fertilizer practice .
• Soil Compaction- Where productivity of soil is reduced because of physical changes to the nature of soil. Frequently associated with surface crusting, plough pans, dispersive clays, excessive cultivation and stock trampling.

Land Degradation
•Land pollution is the degradation of earth's land surfaces often caused by human activities and its misuse. Haphazard disposal of urban and industrial wastes, exploitation of minerals, and improper use of soil by inadequate agricultural practices are a few of the contributing factors. Also, increasing urbanization, industrialization and other demands on the environment and its resources is of great consequence to many countries land surfaces often caused by human activities and its misuse. Haphazard disposal of urban and industrial wastes, exploitation of minerals, and improper use of soil by inadequate agricultural practices are a few of the contributing factors. Also, increasing urbanization, industrialization and other demands on the environment and its resources is of great consequence to many countries We often assume that land degradation only affects soil fertility. However, the effects of land degradation often have more significant impacts on receiving water courses (rivers, wetlands and lakes) since soil, along with nutrients and contaminants associated with soil, are delivered in large quantities to environments that respond detrimentally to their input.
•Land degradation therefore has potentially disastrous impacts on lakes and reservoirs that are designed to alleviate flooding, provide irrigation, and generate hydroelectricity.

Causes of Land and Soil Degradation

The causes of land and soil degradation are mainly anthropogenic and related to agriculture :
1.Land clearance, such as clear cutting and deforestation
2.Agricultural depletion of soil nutrients through poor farming practices
3.Livestock
4.Urban conversion
5.Irrigation
6.Pollution
7.Vehicle Off-roading

Effects of Land & Soil Degradation
The major stresses on land and soil include:
1.Accelerated soil erosion by wind and water
2.Soil acidification or alkalinisation
3.Salination
4.Destruction of soil structure including loss of organic matter
5.Derelict soil
•Severe land degradation affects a significant portion of the earth's arable lands, decreasing the wealth and economic development of nations. As the land resource base becomes less productive, food security is compromised and competition for dwindling resources increases, the seeds of famine and potential conflict are sown.

ENERGY RESOURCES
Energy is defined by physicists as the capacity to do work. Energy is found on our planet in variety of forms, some of which are immediately used, while others require a process of transformation. The sun is the primary energy source. Most of the world’s energy comes from fossil fuels eg. oil, coal , natural gas etc. Energy is used for household use, agriculture, production of industrial goods and for transport.

ENERGY NEEDS
Energy has always been closely linked to man’s economic growth and development. The world’s demand for electricity has doubled over the last 22 years. Electricity is at present the fastest growing form of energy used worldwide. For almost 200 years coal was the primary energy source. At the end of the 20th century, oil accounted for 39 %, coal 24%,natural gas 24%, nuclear 7%,hydropower 6%.
In India as estimated in 2000 coal is predominant source accounting for 55% , oil 31%, natural gas 8%, hydro 5%, nuclear power 1%, biomass 40%,the use of natural gas has increased rapidly in the 80s and 90s.

TYPES OF ENERGY
Energy can be classified into:
-Renewable energy.
-Non- renewable energy.

Renewable energy : These are constantly replaced and are usually less polluting eg. Hydropower, solar, wind & geothermal.
Non- renewable energy: These consist of the mineral based hydrocarbon fuels also known as fossil fuels eg. Coal, oil & natural gas. When these are burnt, they produce harmful gases like C02,nitrogen ,C0 etc. causing air pollution.

NON RENEWABLE ENERGY RESOURCES

Coal & Oil As Energy
•Coal is a combustible black or brownish-black sedimentary rock composed mostly of carbon and hydrocarbons. It is the most abundant fossil fuel produced in the United States.
Coal is a nonrenewable energy source because it takes millions of years to create. The energy in coal comes from the energy stored by plants that lived hundreds of millions of years ago, when the earth was partly covered with swampy forests. For millions of years, a layer of dead plants at the bottom of the swamps was covered by layers of water and dirt, trapping the energy of the dead plants. The heat and pressure from the top layers helped the plant remains turn into what we today call coal.

USES OF COAL
•Coal as fuel
• Coking and use of coke
• Gasification
• Liquefaction - Coal-To-Liquids (CTL)
• Coal as a traded commodity

Environmental effects of coal:

• release of carbon dioxide and methane, both of which are greenhouse gas
  
• waste products including Uranium, Thorium, and other heavy metals
  
• acid rain
  
• interference with groundwater and water table levels
  
• impact of water use on flows of rivers and consequential impact on other land-uses
  
• dust nuisance
  
• subsidence above tunnels, sometimes damaging infrastructure
  
• rendering land unfit for the other uses.
  
  

OIL-PETROLEUM

• OIL together with natural gas, it makes up petroleum, which is Latin for "rock oil". Petroleum is basically a mix of naturally occurring organic compounds from within the earth that contain primarily hydrogen, carbon and oxygen. When petroleum comes straight out of the ground as a liquid it is called crude oil if dark and viscous, and condensate if clear and volatile. When solid it is asphalt, and when semi-solid it is tar. There is also natural gas, which can be associated with oil or found alone.
  

•ENVIRONMENTAL IMPACT
An oil spill is the release of a liquid petroleum hydrocarbon into the environment due to human activity, and is a form of pollution. The term often refers to marine oil spills, where oil is released into the ocean or coastal waters. The oil may be a variety of materials, including crude oil, refined petroleum products (such as gasoline or diesel fuel) or by-products, ships' bunkers, oily refuse or oil mixed in waste. Spills take months or even years to clean up.
Oil is also released into the environment from natural geologic seeps on the sea floor. Most man-made oil pollution comes from land-based activity, but public attention and regulation has tended to focus most sharply on seagoing oil tankers.

USES of OIL
•Food oils
Many edible vegetable and animal oils, and also fats, are used for various in cooking and food preparation..
• Fuel
Almost all oils burn in air generating heat, which can be used directly, or converted into other forms of energy by various means. Egs petroleum, fuel oil, diesel oil, petrol (gasoline), etc), though biological oils such as biodiesel are gaining market share.
•Heat transport
Many oils have higher boiling points than water and are electrical insulators, making them useful for liquid cooling systems, especially where electricity is used.
• Lubrication
Due to their non-polarity, oils do not easily adhere to other substances. This makes oil useful as lubricant for various engineering purposes.
•Petrochemicals
Crude oil can be processed into plastics and other substances.

Natural gas

•A gas used as a fuel, which is formed naturally in the earth when organic material decomposes under pressure.

Uses
•Power generation
Natural gas is a major source of electricity generation through the use of gas turbines and steam turbines
•Hydrogen
Natural gas can be used to produce hydrogen, with one common method being the hydrogen reformer. Hydrogen has various applications: it is a primary feedstock for the chemical industry, a hydrogenating agent
•Natural gas vehicles
Compressed natural gas (methane) is used as a cleaner alternative to automobile fuels
•Fertilizer
Natural gas is a major feedstock for the production of ammonia, for use in fertilizer production
•Residential domestic use
Natural gas is supplied to homes, where it is used for such purposes as cooking in natural gas-powered ranges and/or ovens, natural gas-heated clothes dryers
•Other
Natural gas is also used in the manufacture of fabrics, glass, steel, plastics, paint, and other products

RENEWABLE SOURCE OF ENERGY

WIND POWER
Wind was the earliest energy source used for transportation by sailing ships. Wind power is the fastest growing of the renewable energy technologies, though it currently provides less than 0.5 percent of global energy. Denmark and Californai have large wind turbine cooperatives, which sell electriciry to the government. In Tamil Nadu there are large wind farms producing 850 mw of electricity. At present India is the third largest producer of wind energy in the world.
Over the past two decades, a great deal of technical progress has been made in design, siting, installation, operation and maintenance of wind- mills.These improvements have led to heigher wind conversion and lower electricity production cost.

Environmental Impacts: Has very few environmental impacts. Wind power is renewable and produces no greenhouse gases during operation, such as carbon dioxide and methane. The principal problems are bird kills, noise. Wind is an intermittent source depending on the geographic distribution of wind, therefore it cannot be used as the sole source of elctricity and requires some other electricity source.

HYDROPOWER
Hydropower or hydraulic power is the force or energy of moving water. It may be captured for some useful purpose Prior to the widespread availability of commercial electric power, hydropower was used for irrigation, and operation of various machines, such as watermills, textile machines, and sawmills. Today the largest use of hydropower is for the creation of hydroelectricity, which allows low cost energy to be used at long distances from the water source.Since water is about 800 times denser than air even a slow flowing stream of water, or moderate sea swell, can yield considerable amounts of energy. The water flowing down a natural gradient can be used to turn the turbines to generate electricity known as ‘hydroelectric power’ by constructing dams across the rivers.
Drawbacks:
To produce hydroeletric power, large areas of forest and agricultural lands are submerged. These lands provide a livelihood for local tribalpeople and farmers. The silting of the reservoirs reduse the life of the hydroelectric poer installations.

SOLAR ENERGY
The sun has the largest quantum of energy. It is estimated that solar energy falling each day on earth is more than the total amount of energy the inhabitants of the world would consume in 27 years. The amount of sunlight varies greatly depending on geographical location, time of day, season and clouds.
In the last few decades, increasing environmental problems and declining fossil fuel resources have forced us to look at this tremendous source.

USE OF SOLAR ENERGY
Solar energy technologies offer a clean, renewable and domestic energy source. Solar energy technologies have made huge technological and cost improvements. Researchers continue to develop technologies that will make solar energy technologies( power generating technologies) cost competitive with fossil fuels.
Few applications of solar energy:

• Solar heating for homes.
  
• Solar water heating.
  
• Solar cookers.
  
• Solar thermal electric power.
  
• Photovoltaic energy .
  
• Solar desalination systems.
  
  

BIOFUEL

Biofuel Definition
•Gas or liquid fuel made from plant material (biomass). Includes wood, wood waste, wood liquors, peat, railroad ties, wood sludge
Biofuel are derived from biomass. They differ from fossil fuels in that they are derived from renewable sources, including crops, animal waste and some forms of ‘rubbish’.

TYPES OF BIOFUEL

• First generation biofuel
  'First-generation fuels' refer to biofuel made from sugar, starch, vegetable oil, or animal fats using conventional technology
  
• Second generation biofuel
  Supporters of biofuel claim that a more viable solution is to increase political and industrial support for, and rapidity of, second-generation biofuel implementation from non food crops, including cellulosic biofuel. Second-generation biofuel production processes can use a variety of non food crops
  
• Third generation biofuel
  Algae fuel, also called oilgae or third generation biofuel, is a biofuel from algae. Algae are low-input/high-yield (30 times more energy per acre than land) feedstock to produce biofuel[ and algae fuel are biodegradable
  
  EXAMPLES OF BIOFUEL
  

Vegetable oil
•Vegetable oil can be used for either food or fuel; the quality of the oil may be lower for fuel use. Vegetable oil can be used in many older diesel engines

Biodiesel.
•Oils are mixed with sodium hydroxide and methanol (or ethanol) and the chemical reaction produces biodiesel (FAME) and glycerol. 1 part glycerol is produced for every 10 parts biodiesel.

Solid Biofuel
•Examples include wood, charcoal, and dried manure

Biogas

Biogas is the biofuel substitute for natural gas. It derives from organic waste materials including animal waste and waste generated from municipal, commercial and industrial sources through the process of anaerobic digestion.


Benefits of use of biofuel

The main practical benefit of using biofuel alternatives is that they are easily integrated with fossil fuels and can be used within existing energy systems. .There are main environmental benefits of using biofuel in place of fossil fuels.

• nontoxic ,biodegradable & renewable,
• help reduce dependence on foreign oil
  
• oxygenated fuel, so it burns more completely than other fossil-based products
  
• biofuel offer the potential for long-term, secure energy supplies
  
• relatively cheap,.
  
• biofuels contribute significantly less to greenhouse gas emissions in their production and use than oil or natural gas.
  
• Helps in waste management
  
• Restores ecosystem