man and environment 6 natual sources

7/28/2019 Man and Environment 6 Natual Sources

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NATURAL RESOURCES


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Resources ornatural resources are any form of matter or energyobtained from the physical environment that meet human needs. This

definition of natural resources is not as simple as it appears. Most

resources are created by human ingenuity. Oil was once a uselessfluid until humans learned how to locate it, extract it from the ground,

and separate it by distillation into various components such as

gasoline, home heating oil, and road tar.

Similarly, coal and uraniumwere once useless rocks.

Something may become

useful or useless for human

needs as a result of changes

in the technology of resourceextraction and processing

Whether something is classified as a resource depends on technology,

economics, cultural beliefs, and the environmental effects of finding and

using it.


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Natural resources are often classified :

Renewable resources are generally living

resources (fish, and forests, for example), which

can restock (renew) themselves if they are notoverharvested.

Non-renewable resources is a natural resource

that cannot be re-made or re-grown. Often fossilfuels, such as coal, petroleum and natural gas are

considered non-renewable resources.


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The maximum rate at which a renewable resource

can be used without impairing or damaging its

ability to be renewed is called its maximum

sustained yield. If this yield is exceeded a

potentially renewable resource is then converted

to a nonrenewable resource.

Recycling involves collecting and remelting or

reprocessing a resource, whereas reuse involvesusing a resource over and over again in the same

form.


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On the basis of their stages of developments,

resources can be classified into both Actual and

Potential resources:

The resources pass through various stages of

development before they are actually available. The

resources held actually in stock are called Actualresources. Even the actual source of resources may

not be possible to be used to their full. The portion

that can be used profitably with the help of available

technology is termed as Potential resourcs. The size

and quantity of a potential resource may change

with changes in technology and time.


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Resources can also be classified on

biotic and abiotic:

Biotic resources are derived from animals and

plants (livingworld).

Abiotic resouces are derived from the non-

living world e.g. land, water, and air. Mineral and

power resources are also abiotic resources someare derived from nature.


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Natural capital Natural resources are natural capital converted

to commodity inputs to infrastructural capital

processes. They includesoil, timber, oil, minerals,

and other goods taken more or less as they arefrom the Earth.


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Nations status

A nation's natural resources often determine its wealth

and status in the world economic system, by

determining its political influence. Developed nationsare those which are less dependent on natural resources

for wealth, due to their greater reliance on

infrastructural capital.

For example, the United States used coal as an export in the early1900s, and also as a main resource fuel in key industries for production.

Eventually, as transportation costs went down with time, minerals used as

resources became commodities and were traded at world prices.


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Conflicts for resources

In recent nears, the depletion of natural capital and

attempts to move to sustainable development have

been a major focus of development agencies. This is ofparticular concern in rainforest regions, which hold

most of the Earth's natural biodiversity - irreplaceable

genetic natural capital. Conservation of natural

resources is the major focus of Natural Capitalism,environmentalism, the ecology movement, and Green

Parties. Some view this depletion as a major source of

social unrest and conflicts in developing nations.


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Natural resources

Ecoregion Geostrategy

Sustainable forestry

Fish

Wood Metal

Minerals

List of natural gas fields

List of minerals

Petroleum politics

Mining

Mineral exploration Refining

Prospecting

Soft energy path

Environment Landscape

Land (economics)

Soil

Causes of war

Pure water


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DESCRIPTION An ecoregion, sometimes called a bioregion, is a relatively

large area of land or water that contains a geographically distinctassemblage of natural communities.

Geostrategy is a subfield of geopolitics. As with all strategies,

geostrategy is concerned with matching means to ends - in this

case, a country's resources (whether they are limited or extensive)with its geopolitical objectives (which can be local, regional, or

global).

Sustainable forestry is a forest management concept. The basic

tenet of sustainable forestry is that the amount of goods andservices yielded from a forest should be at a level the forest is

capable of producing without degradation of the soil, watershed

features or seed source for the future.


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Minerals are natural compounds formed through geologicalprocesses. The term mineral encompasses not only the

material's chemical composition, but also theminerals structure.

Petroleum politics have been an increasingly important aspect

of international diplomacy since the discovery of oil in the

Middle East in the early 1900s.

Mining is the extraction of valuable minerals or other geologicalmaterials from the earth, usually (but not always) from an ore

body, vein, or (coal) seam. Mineral exploration is the process undertaken by companies,

partnerships or corporations in the endeavour of findingcommercially viable concentrations of ore to mine.


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Refining is the process of purification of a substance. The termis usually used of a natural resource that is almost in a usableform, but which is more useful in its pure form.

Prospecting is the act of physically searching for minerals,fossils, precious metals or mineral specimens, and is essentially

analagous to fossicking. The soft energy path is an energy use and development strategy

delineated and promoted by some energy experts and activists,such as Amory Lovins and Tom Bender; in Canada, DavidSuzuki has been a very prominent (if less specialized) proponent.

The natural environment comprises all living and non-living

things that occur naturally on Earth. In its purest sense, it is thusan environment that is not the result of human activity or

intervention.


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A landscape comprises the visible features of an area of land,

including physical elements such as landforms, living elements of

flora and fauna, abstract elements such as lighting and weather

conditions, and human elements, for instance human activity orthe biult environment.

In economics, land comprises all naturally occurring resources

whose supply is inherently fixed, such as geographical locations

(excluding infrastructural improvements and perhaps naturalcapital, which can be degraded by human actions), mineral

deposits, and even geostationary orbit locations and portions of

the electromagnetic spectrum.

Soil is the collection of natural bodies that form in earthymaterial on the land surface. The term is popularly applied to the

material on the surface of the earth's moon and Mars, a usage

acceptable within a portion of the scientific community.


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RESOURCESSometimes people have resources and they

dont use it or they think that they dont

have!


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Suns type Energy and Impact on

Earth


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SOLAR POWEREnergy from the Sun in the form of insolation from sunlightsupports almost all life on Earth via photosynthesis, and drives theEarth's climate and weather.

Solar poweris the technology of obtaining usable energy from the light ofthe Sun. Solar energy has been used in many traditional technologies forcenturies and has come into widespread use where other power suppliesare absent, such as in remote locations and in space.

Highest insolation areas


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REMOTE PLACES DEVICES


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APLICATIONSSolar energy is currently used in a number of applications:

Heating (hot water, building heat, cooking)

Electricity generation (photovoltaics, heat)

Desalination of seawater

Its application is spreading as the environmental costs and limited supply of

other power sources such as fossil fuels are realized.


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Basic Resource (Sun)

Clean Energy

Necessary to know quantity and quality of solar energy available to install devices

Solar Radiation ( Insolation ) is variable from place to place

Leads to different orientations of devices to intercept solar energy

Check Serpa Portugy

www

SUN ENERGY CAPTING DEVICES

Photovoltaic cells


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tovoltaic modules that began generating electricity at one of the world's largest solar powe

Credit: Business Wire


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TYPES OF TECHNOLOGIESSolar Hot Water Use sunlight to heat water

Used to heat domestic water or for space heating

Compose by solar solar thermal collectors and a storage tank

The three basic classifications of solar water heaters are:

Active systems which use pumps to circulate water or

a heat transfer fluid

Passive systems which circulate water or a heat

transfer fluid by natural circulation. These are also

called thermosiphon systems

Batch systems using a tank directly heated by sunlight


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HEAT WATER FUNCTIONING


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SOLAR COOKING

Solar cooking is helping many developing countries, both reducing the

demands for local firewood and maintaining a cleaner environment for the

cooks.

Solar Box CookingTraps the suns energy in a insulated box

used for cooking

used for Pasteurization

used for fruit canning


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SOLAR LIGHTING

Solar Daylighting Use natural daylight to provide illumination

offsets energy use in electric lighting systems

use of natural light also offers physiological and psychological

benifits. Builiding orientation, exterior shading, sawtooth roofs,

clerestory windows, light shelves, skylights and light tubes are

among the many daylighting features. These features may be

incorporated in existing structures but are most effective when

integrated in a solar design package which accounts for factorssuch as glare, heat gain, heat loss and time-of-use


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SOLAR LIGHTING FUNCTIONING

Insulation ( light )


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PHOTOVOLTAICS

NOTE: Until recently, their use has been limited because of high manufacturing costs.

Photovoltaics devices or banks of devices that use the photovoltaic effect of

semiconductors to generate electricity directly from sunlight

used in very low-power devices such as calculators with

LCDs.

used in remote applications such as roadside emergency

telephones, remote sensing, cathodic protection of pipe lines,

and limited "off grid" home power applications. A third use has

been in powering orbiting satellites and other spacecraft.


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PHOTOVOLTAICS FUNCTIONING

Photovoltaics bank cellsPhotovoltaics panels cells in a yatch


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POWER TOWERSPower Towers Know as 'central tower' power plants or 'heliostat' power

plants (power towers) use an array of flat, moveable mirrors (called

heliostats) to focus the sun's rays upon a collector tower (the target). The

high energy at this point of concentrated sunlight is transferred to a

substance that can store the heat for later use.

Used to generate electricity


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POWER TOWERS FUNCTIONING


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CONCENTRATING COLLECTOR WITH STIRLING ENGINE

CONCENTRATING COLLECTOR WITH STIRLING ENGINE Solar energy

converted to heat in a concentrating (dish or trough parabolic) collector can

be used to drive a Stirling engine*. The Stirling engine is a type of heat

engine which uses a sealed working gas (i.e. a closed cycle) and does notrequire a water supply

Holds the record for converting solar energy into electricity (30 percent

at 1,000 watts per square meter).

Produce little or no power in overcast conditions and incorporate asolar tracker to point the device directly at the sun.

*The Stirling engine is a type of heat engine which uses a sealed working gas (i.e. a closed cycle) and does notrequire a water supply.


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COLLECTOR WITH STIRLING ENGINE FUNCTIONING


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Solar and

diesel

combinated

powered

yacht
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IMPACT ON EARTHSolar activity has several effects on the Earth :

Because the Earth has a magnetic field, charged particles

from the solar wind cannot impact the atmosphere directly, but

are instead deflected by the magnetic field and aggregate toform the *Van Allen belts

The most energetic particles can 'leak out' of the belts and

strike the Earth's upper atmosphere, causing auroras, known as

aurorae borealis in the northern hemisphere and aurorae

australis in the southern hemisphere

*The Van Allen belts consist of an inner belt composed primarily of protons and an outer beltcomposed mostly of electrons. Radiation within the Van Allen belts can occasionally damage

satellites passing through them.


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IMPACT ON EARTH

Vegetation uses photosynthesis to convert solar energy to chemical energyincorporated in biomass. Biomass may be burned directly to produce heat andelectricity or processed into methane (natural gas), hydrogen and other biofuels

Hydroelectric dams and wind turbines are powered by solar energy through itsinteraction with the Earth's atmosphere and the resulting weather phenomena

Ocean thermal energy production uses the thermal gradients present acrossocean depths to generate power. These temperature differences are because ofthe energy of the sun

Fossil fuels are ultimately derived from solar energy captured by vegetation inthe geological past

Sunlight is collected using focusing mirrors and transmitted via optical fibers intoa building's interior to supplement lighting

Indirect solar power involves multiple transformations of sunlight

which result in a useable form of energy:


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Advantages and Disadvantages

The 122 PW* of sunlight reaching the earth's surface is plentifulcompared to the 13 TW** average power consumed by humans.

Solar power is pollution free during use. Production end wastes andemissions are manageable using existing pollution controls.

Facilities can operate with little maintenance or intervention after initialsetup.

Solar electric generation is economically competitive where gridconnection or fuel transport is difficult, costly or impossible. Examplesinclude satellites, island communities, remote locations and oceanvessels.

Advantages :

* Petawatt(1015) ** Terawatt(1012)


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When grid connected, solar electric generation can displace the highestcost electricity during times of peak demand (in most climatic regions),

can reduce grid loading, and can eliminate the need for local batterypower for use in times of darkness and high local demand.

Grid connected solar electricity can be used locally thus minimizingtransmission/distribution losses (approximately 7.2%).

Once the initial capital cost of building a solar power plant has beenspent, operating costs are low when compared to existing powertechnologies.

Advantages :


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Limited power density: Average daily insolation in the E.U. is 3-7 kWh/m2 usable by 7-17.7% efficient solar panels.

Intermittency: It is not available at night and is reduced when there is cloud cover,

decreasing the reliability of peak output performance or requiring a means of energystorage. For power grids to stay functional at all times, the addition of substantial amountsof solar generated electricity would require the expansion of energy storage facilities, otherrenewable energy sources, or the use of backup conventional powerplants

Locations at high latitudes or with substantial cloud cover offer reduced potential for solarpower use

Like electricity from nuclear or fossil fuel plants, it can only realistically be used to powertransport vehicles by converting light energy into another form of energy (e.g. battery storedelectricity or by electrolysing water to produce hydrogen) suitable for transport.

Solar cells produce DC which must be converted to AC when used in currently existingdistribution grids. This incurs an energy penalty of 4-12%

Disadvantages :
http://en.wikipedia.org/wiki/Direct_Currenthttp://en.wikipedia.org/wiki/Direct_Current

man and environment 6 natual sources

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