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Renewable and nonrenewable resources Category: Environment, conservation, and resource management Nature provides numerous energy resources.. Renewable Energy Sources The most abundant r

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ing seismic studies to decode the

in-terior of the Earth; sonar for probing

the ocean floor; and medicine using

X rays and CAT scans

Remote sensing developed from

several origins, both scientific and

technological Technologically, the

telescope, invented in the 1600’s, and

photography, invented in the 1840’s,

were significant advances in our

abil-ity to remotely sense our

environ-ment Then, the discovery of energy

(frequencies) beyond the familiar

vis-ible light, in the 1860’s, by James

Clerk Maxwell (1831-1879)

demon-strated that our eyes were fairly

lim-ited in gathering information that

was available in the universe Couple

this with the aerial perspectives

af-forded by ballooning (developed in the 1780’s), flight

(1900’s), and space travel (1950’s), and humanity’s

concept of its environment and universe changed

dra-matically

Early Earth Resources Satellites

Remote sensing as a stand-alone discipline had a

par-allel development with the space race of the 1950’s

and 1960’s The advantages of a perspective from

space became apparent with the National

Aeronau-tics and Space Administration’s (NASA’s) April 1,

1960, launch of TIROS 1 (the Television Infrared

Ob-servations Satellite), whose mission was to observe

weather patterns The advantages to meteorologists

and weather forecasting were obvious, but there was

other information to be garnered from these types of

images

On July 23, 1972, the first of a series of satellites,

Earth Resources Technology Satellite 1 (ERTS-1), was

launched with the specific mission of remotely

sens-ing the Earth’s surface The success of this mission

en-couraged the launch of a succession of similar

satel-lites with a different name: the Landsat series This

ongoing effort has given the scientific community

de-cades of continuous coverage of the Earth’s surface

Passive vs Active Sensors

These satellites, and others from private companies

and governments other than that of the United States,

carry a variety of imaging scanners that look down

on the Earth and transmit digital images to various

ground stations There are two types of sensors: active and passive Active sensors that transmit to the target and collect bounces back via “radio detection and ranging” (radar) are examples Passive sensors collect energy that is reflected from the target; for example, a camera collects light The majority of remote-sensing satellites utilize multiple passive sensors These are designed to record reflected energy at different elec-tromagnetic frequencies, usually in both the visible and infrared portion of the spectrum The advantage

to combining different frequencies is that more con-trast can be discerned between targets that are similar For example, the green leaf of a corn plant can be dis-tinguished from the green leaf of a watermelon— from space This discrimination is based on the re-flected energy, or the object’s spectral signature

Spectral Signatures The key to interpreting a satellite image is in under-standing the spectral signatures of the various objects

in the image Passive scanners receive the energy from the Sun that is reflected from the target (for example, green plants) After it has passed through the atmo-sphere and interacted with the object, it passes through the atmosphere again and is collected by the satellite’s sensors The atmosphere acts as a filter of some frequencies, and the object itself both absorbs and reflects frequencies The signal (energy) that is reflected into space is different from the energy that left the Sun This altered signal is specific to the object and is its “spectral signature.” Nonliving objects—

The U.S Air Force Lockheed U-2 is a surveillance aircraft capable of accurate remote sensing (United States Air Force)

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rocks, soil, water—tend to have more stable

signa-tures, but plants can vary depending on species, age,

and health

Thematic Mapping

By identifying the spectral signature of a target, all

ob-jects of the same signature can be mapped as the

same, or the same theme This is known as thematic

mapping For example, a cornfield will have a

charac-teristic spectral signature that is different from an

ad-jacent field of potatoes Therefore, by identifying the

spectral signature of the corn, all similar signatures

within the image can be mapped as “corn.” These

im-ages are often color-coded to enhance discrimination

between targets This is known as “false color”

imag-ery because the colors are assigned to enhance

con-trast and are not descriptive of the object as seen in

sunlight As the data are recorded in a digital format,

all of the pixels (picture elements) that compose the

image can be counted and the extent or area of any

signature can be measured For example, an image or

images of the Midwest can be collected, the spectral

signature of a crop (such as corn or wheat), can be

identified, and computer software can calculate the

area of crop on the ground, its health, and its stage of

development

This underscores the advantage of this technology

These types of thematic maps can be made over

re-gional areas with computer speed Geologists using

the perspective of space can map large geologic

struc-tures, identify mineral deposits and potential

fossil-fuel deposits, and inventory surface water resources

Further, in conjunction with land-use planners,

geolo-gists can identify geologic hazards such as floodplains,

sinkholes (karst topography), unstable slopes, and

fault zones Biologists and botanists use

remote-sensing data to map the diversity of plant

communi-ties and even to determine the health of ecosystems

Foresters can inventory timber resources and the

health of forests Farmers can map soil moisture or

identify a frost-damaged orange tree, for example,

be-fore stress becomes obvious to a trained observer on

the ground Land-use planners can map the various

types of land use (urban, suburban, and rural) and

de-termine growth patterns of cities and communities

over time

The Terra System

The mission of NASA’s Terra system (formerly EOS

AM-1), launched in December 18, 1999, is to research

multidisciplinary problems directed primarily by re-searchers from the United States, Japan, and Canada Terra’s broad goals are to investigate Earth systems; interactions among the atmosphere, hydrosphere, biosphere, and lithosphere; and changes in the global climate system Terra has a design life of approxi-mately fifteen years (2000-2015) The five main sen-sors it carries are:

• the Advanced Spaceborne Thermal Emissions and Reflection Radiometer (ASTER), which provides high-resolution imagery over fifteen spectral win-dows; it can develop thematic maps of surface tem-perature (reflectance) and elevation;

• the Clouds and the Earth’s Radiant Energy System (CERES), which measures solar-reflected and Earth-emitted radiation from the Earth’s surface to the top of the atmosphere;

• the Multi-Angle Imaging Spectroradiometer (MISR), which is composed of nine cameras using four different spectral windows; it primarily mea-sures changes of atmospheric energy over time;

• the Moderate-Resolution Imaging Spectroradi-ometer (MODIS), which captures imagery over thirty-six spectral windows and maps the entire Earth in a one- or two-day period; and

• the Measurements of Pollution in the Troposphere (MOPITT), which (as its name implies) monitors pollution changes in the lower level of the atmo-sphere, which has the greatest impact on life

Perspective The science and technology of remote sensing are de-veloping at a critical time for the citizens of the twenty-first century Global population, approaching seven billion in 2009, was expected to be nine or ten billion

by the middle of the twenty-first century At the same time, a long-term trend toward increased socioeco-nomic status for nations such as China and India, com-bined with population, require ever-more resources

to support an interlocking global economy The abil-ity to explore, inventory, and manage natural re-sources to maintain this growth is greatly enhanced However, remote sensing goes beyond the search for raw materials to sustain humanity; it can help manage human resources as well The data assists the under-standing of the Earth’s changing climate, specifically rainfall patterns This has a direct impact on where people can live and future migration patterns By ob-serving the growth of cities and communities over time, these data can assist in the most efficient

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use planning The “big picture” perspective from

space coupled with the speed of computers to

inter-pret this imagery is a timely and welcome tool for the

twenty-first century

Richard C Jones

Further Reading

Campbell, James B Introduction to Remote Sensing 4th

ed New York: Guilford Press, 2007

Jensen, John R Remote Sensing of the Environment: An

Earth Resource Perspective 2d ed Upper Saddle

River, N.J.: Prentice-Hall, 2007

Ustin, Susan L., ed Manual of Remote Sensing: Remote

Sensing for Natural Resource Management and

Environ-mental Monitoring 3d ed New York: Wiley, 2004.

Web Sites

Geoscience and Remote Sensing Society

http://www.grss-ieee.org/

National Aeronautics and Space

Administration

Tutorial on Remote Sensing

http://rst.gsfc.nasa.gov/

National Aeronautics and Space

Administration Earth Observatory

Remote Sensing: Introduction and History

http://earthobservatory.nasa.gov/Features/

RemoteSensing/remote.php

See also: Agriculture industry; Biosphere;

Geo-graphic information systems; Geology; Hydrology

and the hydrologic cycle; use planning;

Land-use regulation and control; Landsat satellites and

sat-ellite technologies; Lithosphere; Population growth;

Resources for the Future; U.S Geological Survey;

Weather and resources

Renewable and nonrenewable

resources

Category: Environment, conservation, and

resource management

Nature provides numerous energy resources

Nonre-newable resources were the primary source of energy for

the twentieth century However, with the depletion of

nonrenewables, interest in renewable forms of energy has generated increasing research and development of renewables.

Background Nonrenewable resources cannot be readily replaced after consumption A renewable resource is one that

is continuously available, such as solar energy, or one that can be replaced within several decades, such as wood

Nonrenewable Energy Sources Nonrenewable resources may be subdivided into four categories: metals (such as copper and aluminum), industrial minerals (such as lime and soda ash), con-struction materials (sand and gravel), and energy resources (coal, oil, and uranium) Of the nonfuel substances, metals are most prone to depletion by overproduction, but recycling can prolong their use-ful lifetime almost indefinitely

Construction materials, although not readily recy-clable, are abundant and ubiquitous in the Earth’s crust, rendering them a virtually unlimited resource Although less plentiful, the most widely used indus-trial minerals are unlikely to be depleted in the near future; on the scale of centuries, however, they are an endangered resource if current levels of production are maintained It is probable that environmental concerns will reduce future production

The major forms of nonrenewable energy produc-tion are fossil fuel combusproduc-tion (using oil and coal) and nuclear fission (using uranium) Of the total en-ergy consumed by Americans, only 7 percent is from renewable resources, while 85 percent is from fossil fuels, predominantly oil

Coal was the first fossil fuel to be used extensively, and it remains the most abundant Coal can be burned directly or converted into petroleum or petroleum products, through the expenditure of additional en-ergy When used as fuel, coal creates many problems Mines are environmentally destructive, and coal is the most difficult fossil fuel to transport When coal

is burned, vast quantities of sulfur compounds (which form sulfuric acid in the atmosphere) are released, while the carbon in the coal becomes carbon dioxide,

a greenhouse gas believed to contribute to global warming The carbon in coal also has many other valuable (nonpolluting) uses in the chemical in-dustry

Oil is the world’s major source of energy because it

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is abundant and relatively inexpensive Its high rate of

use will result in its depletion during the twenty-first

century When burned as gasoline in cars, it releases

carbon dioxide; various dangerous air pollutants,

such as carbon monoxide and nitrogen oxides; and

uncombusted hydrocarbons (a major cause of

photo-chemical smog) Natural gas, formed when organic

materials decompose, is usually found with petroleum

reservoirs Its supply, rate of consumption, and

proba-ble future are comparaproba-ble to those of petroleum It is

widely used because it is relatively inexpensive, clean,

and nonpolluting (although it does add carbon to the

atmosphere)

Tar sands, principally found in Canada, are a

low-grade source of petroleum that is feasible to mine and

process only when oil prices are relatively high Two

additional problems limit this source: About as much

energy is required to extract usable oil as is

cre-ated when it is combusted, and the process has

raised environmental concerns Oil shales,

abun-dant in the western United States, appear

theoret-ically to be a major source of future petroleum

products The amount of oil tied up in shale

ex-ceeds the remaining total world reserve of oil To

extract oil, however, the shale must be mined and

heated by processes requiring large quantities of

water in regions where water is scarce

Addi-tionally, the total energy required for extraction

exceeds the energy created when the oil is

burned

Nuclear reactors produce energy through

con-trolled fission of uranium 235 No air pollution is

produced, the mining operations are relatively

small and safe, and the resource being consumed

has no other known use On the other hand,

reac-tor technology is sophisticated and elaborate,

and complicated devices are prone to

break-downs A reactor breakdown can have disastrous

consequences if radioactive materials are released

into the environment Of equal or greater

con-cern is how the by-products of nuclear power

pro-duction—nuclear waste—should be disposed of

over the long term

Renewable Energy Sources

The most abundant renewable energy resource is

solar energy, the source of most other renewables

as well as the original source of fossil fuels The

supply is enormous and inexhaustible, but most is

wasted because it occurs in a dilute form that

re-quires expensive hardware to concentrate Also, it reaches Earth in its most dilute form during the win-ter, when it is most needed for heating In cloudy re-gions it is not even available when demand for it is greatest

Like solar energy, wind represents a large and po-tentially inexhaustible source of energy However, when wind energy is used to generate electricity, ex-pensive collectors are required Wind energy is not feasible everywhere, and even when feasible it is not always available Power derived from moving water, such as that provided by hydroelectric dams, makes an important contribution to the world’s energy supply Many of the best sites have already been dammed, however, and development of a number of other sites

is unwise because of ecological reasons or the sites’ scenic beauty

A man hauls aluminum stoves through a street in Kabul, Afghanistan Aluminum is a nonrenewable resource (Zabi Tamanna/Xinhua/

Landov)

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Tidal energy utilizes the ebb and flow of tides to

create electricity by trapping seawater at the extremes

of high and low tide and releasing it through turbines

Although a potentially large energy source, it is

eco-nomically feasible only where there are naturally high

tides (4.5 meters or more) and where a narrow inlet

encloses a large bay

Geothermal energy uses the heat from natural hot

springs to create steam to power turbines, which are

used to create electricity Because the heat must be

close to the surface, there are few known sites from

which geothermal electrical energy can be extracted

economically Also, because pipelines must be run

over many hectares to collect steam, the

power-gener-ating stations tend to be ugly and noisy

Vegetation (biomass) energy uses plants or animal

products derived from plants as a source of fuel This

source includes wood, organic wastes, ethanol, and

methane gas from biodigestion This type of

renew-able resource is renewrenew-able only if harvesting is

con-trolled and if resources exist to cultivate the source

Thus, trees must be given sufficient time to mature,

and corn must be cultivated before ethanol can be

produced Although vegetation has a long history as a

source of fuel, efficient and sustainable techniques

have yet to be introduced

George R Plitnik

Further Reading

Boyle, Godfrey, ed Renewable Energy 2d ed New York:

Oxford University Press in association with the

Open University, 2004

Cassedy, Edward S., and Peter Z Grossman

Introduc-tion to Energy: Resources, Technology, and Society 2d ed.

New York: Cambridge University Press, 1998

Evans, Robert L Fueling Our Future: An Introduction to

Sustainable Energy Cambridge, England: Cambridge

University Press, 2007

González, Pablo Rafael Running Out: How Global

Shortages Change the Economic Paradigm New York:

Algora, 2006

Greiner, Alfred, and Willi Semmler The Global

Envi-ronment, Natural Resources, and Economic Growth New

York: Oxford University Press, 2008

Hinrichs, Roger A., and Merlin Kleinbach Energy: Its

Use and the Environment 4th ed Belmont, Calif.:

Thomson, Brooks/Cole, 2006

Kozlowski, Ryszard, Gennady Zaikov, and Frank Pudel,

eds Renewable Resources: Obtaining, Processing, and

Applying Hauppauge, N.Y.: Nova Science, 2009.

Kruger, Paul Alternative Energy Resources: The Quest for

Sustainable Energy Hoboken, N.J.: John Wiley &

Sons, 2006

Pimentel, David, ed Biofuels, Solar, and Wind as

Renew-able Energy Systems: Benefits and Risks New York:

Springer, 2008

Twidell, John, and Tony Weir Renewable Energy

Re-sources 2d ed New York: Taylor & Francis, 2006.

See also: Coal; Ethanol; Geothermal and hydrother-mal energy; Hazardous waste disposal; Hydroenergy; Nuclear energy; Nuclear waste and its disposal; Oil and natural gas distribution; Oil shale and tar sands; Solar energy; Tidal energy; Wind energy; Wood and charcoal as fuel resources

Reserve Mining controversy

Category: Historical events and movements Date: 1968-1980

The Reserve Mining Company was successfully prose-cuted for disposing of hazardous waste from its taco-nite mining into Lake Superior.

Definition The Reserve Mining controversy involved the dis-charge of taconite tailings into Lake Superior by the Reserve Mining Company The discharge created con-cern about health and environmental impacts and led to litigation The courts ruled against Reserve Mining

Overview The Reserve Mining Company was established in

1939 to mine taconite ores at Babbitt, Minnesota, on the Mesabi Iron Range Taconite is a low-grade iron ore that requires a processing facility to concentrate and pelletize the ore before it can be used The com-pany decided that the best way of disposing of the re-sulting tailings (waste) was by discharging them into Lake Superior The selected site was located at Silver Bay on the Lake Superior shore near Duluth The nec-essary permits were granted in December, 1947, and operations began in 1955 Within ten years, annual pellet output capacity at the processing plant had reached 9.7 million metric tons, with a water volume

of 1.9 million liters per minute

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There had been little concern about the tailings

discharge into Lake Superior at the permit hearings

or during the initial years of operation except by sport

fishermen This situation changed when the

Stod-dard report by the Department of the Interior and

state agencies in 1968 concluded that Reserve Mining

was polluting Lake Superior in violation of its permits

The report noted concerns about “green” water, trace

metals, fish mortality, asbestos-like fibers, and lake

eutrophication being associated with the discharge

This report was strongly rejected by Reserve Mining

There was growing concern about the tailings

dis-charge by the public as well, which led to citizen

groups fighting against it An unsuccessful series of

conferences was held to try to resolve the issues The

Environmental Protection Agency took over for the

Department of the Interior in 1970, and a lawsuit was

filed in federal court in 1972 to stop the discharge

As the trial began in 1973, a new finding changed

the entire focus of the environmental concern It was

determined that the asbestos-like fibers in the ore

were present in the drinking water of nearby

commu-nities such as Duluth, creating a concern about the

ef-fects on human health Duluth was forced to build a

filtration system that cost $6.9 million The initial

court judgment in 1974 ruled that the discharge must

stop A stay was given by the appeals court while an

ac-ceptable on-land site was to be located and developed

After the first judge was removed by the appeals court

for bias against Reserve Mining, the second judge also

found against Reserve Mining Reserve Mining and its

owners, Armco and Republic, were required to pay

more than $1 million in fines and to pay for the cost of

filtering Duluth’s drinking water before the filtration

plant was ready With the approval of an on-land

dis-posal site, discharge into Lake Superior ended in

1980

Gary A Campbell

See also: Environmental law in the United States;

Environmental Protection Agency; Eutrophication;

Lakes; Mining wastes and mine reclamation; Water

pollution and water pollution control

Residual mineral deposits

Categories: Geological processes and formations;

mineral and other nonliving resources

Residual mineral deposits are formed by chemical weathering processes that dissolve and remove unsired constituents of rocks, leaving behind valuable de-posits of insoluble minerals Examples include bauxite and residual iron, manganese, nickel, phosphate, and clays.

Background Residual mineral deposits are the result of residual concentration, a process whereby weathering removes undesired constituents from rock to leave behind a concentration of valuable minerals This residue, which is able to withstand further chemical weather-ing, can accumulate to form commercially significant deposits Important deposits of iron, aluminum, man-ganese, nickel, phosphate, clays, and other economic minerals have been formed by residual concentra-tion

Formation Residual mineral deposits form from rocks that con-tain valuable minerals that are either insoluble or al-ter to form insoluble compounds upon weathering; the undesired components of the rock are relatively soluble As the rocks undergo chemical weathering, the unwanted materials are gradually dissolved and carried away If the outcrop surface has low relief (so that physical weathering processes cannot remove sig-nificant amounts of the insoluble residues) and if the terrain remains stable over a period of time long enough to allow the residues to accumulate, a residual deposit can form Because chemical weathering is a slow process and the materials being removed (such

as calcite, feldspar, clay, and quartz) are often only slightly soluble, it may take millions of years for a re-sidual accumulation to develop that is of sufficient pu-rity and volume to be of commercial importance Warm, humid conditions are most conducive to the formation of residual deposits While ores can de-velop through residual concentration in a temperate climate, tropical and subtropical environments host a greater variety of residual deposits

Characteristics Residual mineral deposits frequently occur in regions where the climate is or was humid, subtropical, or tropical They form in relatively level depositional en-vironments, where physical weathering processes ex-ert a minimal influence The presence of iron oxides concentrated in the weathering zone typically imparts

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a deep red or brown color to deposits formed by

resid-ual concentration The removal of soluble material

generally leaves the deposits with a porous texture or

with a consistency resembling that of loose soil

Resid-ual deposits are usResid-ually underlain by the rock from

which they were derived

A particular form of residual deposit, laterite, is

characteristic of the hot, humid tropics Laterite is a

highly weathered red soil or surface material that is

rich in iron and aluminum oxides and hydroxides A

lateritic deposit forms after intense chemical

weather-ing has leached the parent rock of most of its silica

Al-ternating wet and dry seasons, high drainage rates,

and minimal physical erosion all contribute to laterite

formation

Residual Iron

Iron is present in most rocks, and residual iron

depos-its, including laterites, are widely distributed within

nonglaciated regions Residual concentration of iron

is particularly likely where limestone or extremely

iron-rich silicate rocks are exposed to warm, humid

conditions Significant residual-iron deposits include

those found in the southeastern United States, Brazil,

Venezuela, the West Indies, southern Europe, Africa,

and India

Residual Aluminum (Bauxite)

Bauxite, the chief ore of aluminum, is a lateritic

de-posit formed by residual concentration in tropical or

subtropical regions A mixture of several hydrated

aluminum oxides, bauxite deposits result from the

de-composition of aluminum silicate rocks that are high

in aluminum silicates and low in iron and free quartz

Warm rain water, groundwater, oxygen, carbon

diox-ide, and humic acid interact to break down the parent

rock The French deposits at Baux, from which

baux-ite derives its name, formed from limestones or clays

in limestones In Arkansas, Brazil, and French

Gui-ana, the source rock is nepheline syenite, an intrusive

igneous rock composed largely of alkali feldspars and

feldspathoids (minerals similar to feldspars but

con-taining less silica) Deposits in India formed from

ba-salt; those in Georgia, Alabama, Jamaica, and Guyana

derived from clays; those in Ghana originated from

clay shales and other aluminum-rich rocks; and those

in Thailand derived from clay alluvium Most bauxites

were formed between the middle Cretaceous and

middle Eocene times

Residual Manganese, Nickel, Phosphate, and Clays

Residual deposits of manganese form under condi-tions similar to those that produce residual iron Re-sidual manganese deposits are commonly derived from crystalline schists, limestones previously enriched with manganese minerals, or primary deposits of man-ganese minerals Important residual manman-ganese de-posits include those found in Brazil, Romania, Mo-rocco, Egypt, Ghana, India, Japan, Malaysia, and the Philippines

Under tropical and subtropical conditions, some low-silica igneous rocks decompose to produce hy-drous silicates of nickel and magnesium Nickel lat-erite derived from serpentinized peridotite is found

in New Caledonia, Cuba, Brazil, and Venezuela In Florida, the leading phosphate-producing state, resid-ual concentrations of “land-pebble phosphate” occur Weathering and solution of phosphate-containing Mio-cene limestones left behind this loose, easily mined residue of calcium phosphate pebbles and boulders

In a humid, temperate climate, the chemical weathering of aluminum-bearing rocks produces clay Weathering does not proceed far enough to remove silica and produce a laterite, as in tropical regions; in-stead, the aluminum and silica combine to form hy-drous aluminum silicates—clay minerals Crystalline rocks that contain abundant feldspars and little iron, such as granite and gneiss, are the primary source rocks for clay formation High-grade residual clays oc-cur in the southern and western United States, En-gland, France, Germany, eastern Europe, and China

Other Residual Deposits Other products of residual concentration include trip-oli, an earthy material composed almost entirely of sil-ica and derived from weathered chert or silsil-ica-rich limestone; the residual kyanite deposits of India and the eastern United States; the residual barite deposits

of Missouri; the nodular zinc ores of Virginia and Ten-nessee; and the residual gold accumulations in the United States, Brazil, Madagascar, and Australia

Karen N Kähler

Further Reading

Chamley, Her vé Clay Sedimentology New York:

Springer, 1989

Evans, Anthony M Ore Geology and Industrial Minerals:

An Introduction 3d ed Boston: Blackwell Scientific,

1993

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Guilbert, John M., and Charles F Park, Jr The Geology of

Ore Deposits Long Grove, Ill.: Waveland Press, 2007.

Jensen, Mead L., and Alan M Bateman Economic

Min-eral Deposits 3d ed New York: Wiley, 1979.

McFarlane, M J Laterite and Landscape New York:

Aca-demic Press, 1976

Misra, Kula C Understanding Mineral Deposits Boston:

Kluwer Academic, 2000

Robb, Laurence Introduction to Ore-Forming Processes.

Malden, Mass.: Blackwell, 2005

Valeton, Ida Bauxites New York: Elsevier, 1972.

See also: Aluminum; Clays; Iron; Manganese; Nickel;

Phosphate; Secondary enrichment of mineral

depos-its; Silicates; Weathering

Resource accounting

Category: Social, economic, and political issues

Resource accounting (RA), which is also called

envi-ronmental resource accounting or green accounting,

refers to accounting systems designed to revise or

sup-plement the conventional system of national accounts

(SNA), which is used by national governments and by

the United Nations The conventional system does not

consider resource depletion or environmental

degrada-tion.

Background

In traditional economics, the system of national

ac-counts (SNA) measures both a country’s output of

goods and services and the country’s income It is

used as an indicator of national economic activity and

economic performance However, the SNA does not

fully incorporate natural resources in measuring the

national product and does not take account of the

de-pletion of natural resources or the degradation of the

environment in measuring economic performance

Resource accounting (RA) revises or supplements

SNA calculations to correct these omissions

There is no standardized system of resource

ac-counting A wide variety of accounting systems have

been proposed by economists, depending in part on

the purposes to be served by the accounts and the

methods used for measuring the relevant variables

Some systems are designed to revise the conventional

SNA, but in most cases the authors propose

supple-ments to the SNA Resource accounting has been used for analyzing the conditions for sustainable de-velopment, for shaping national economic policies, and for measuring environmental and economic per-formance The United Nations and the World Bank have published analytical studies on RA, and national accounts using RA models have been prepared for a number of countries, including Indonesia, Papua New Guinea, and Mexico In his April, 1993, Earth Day speech, President Bill Clinton called on the Bureau of Economic Analysis to produce “Green GDP [gross do-mestic product] measures that would incorporate changes in the natural environment into the calcula-tion of nacalcula-tional income and wealth.” The U.S Depart-ment of Commerce has published articles on RA and has prepared RA satellite accounts for use as supple-ments to the department’s SNA

RA Adjustments to SNA Resource accounting provides for the following types

of revisions of, or supplements to, the existing system

of national accounts estimates First, account can be taken of the changes in physical amounts of natural resources that result from human activities Natural resources are regarded as capital assets subject to de-pletion and degradation in a manner analogous to the depreciation of assets such as buildings and ma-chinery In the SNA, depreciation of manmade capi-tal is deducted from the GDP in calculating the net national product (NNP), but there is no deduction for depletion or degradation of natural resource capi-tal Supporters of RA argue that the failure to deduct natural resource depletion and degradation in calcu-lating net national product or national income is im-proper because output from natural resource deple-tion is no longer available for consumpdeple-tion after the resources are exhausted This concept is in accor-dance with the economic principle that true income cannot include capital consumption In RA case stud-ies, soil erosion, deforestation, and the depletion of mineral reserves are considered as major reductions

in the GDP Some models also include the deteriora-tion of water supplies and air polludeteriora-tion

Second, account can be taken of the final services provided by natural resources and the environment, such as aesthetic benefits from wilderness areas and biological diversity, both of which contribute to the quality of human life If these services are impaired by human production and consumption, national in-come and product accounts are adjusted for the

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duction of these services For example, when a dam

destroys the scenic value of a canyon, the reduction in

the amenities provided by the canyon is regarded as a

cost to be deducted from the output attributed to the

construction of the dam

Third, SNA expenditures for environmental

pro-tection, such as pollution abatement, can be regarded

as costs of production rather than being included in

national income The recycling of waste material and

the cleaning of waste dumps are also regarded as costs

of production

Analytical Problems

Full accounting by RA systems for the adjustments

listed above involves a number of analytical problems

For example, all RA systems adjust for mineral reserve

depletion, but economists do not agree on the proper

method of calculating depletion One simple method

is to multiply annual mineral output by the average

price of the mineral products and then deduct the

cost of labor and capital required for extraction and

exploration However, this method does not take into

consideration the net income produced by the

min-eral, since the entire output is attributed to depletion

A more accurate variation of this approach is to

esti-mate the reduction in the capital value of a mineral

between two periods during which extraction has

taken place The problem here is that capital values

can change because of a change in the price of the

mineral or the cost of producing it, or because of a

change in the volume of mineral reserves not related

to extraction

An alternative method, called the user-cost method,

divides annual revenue from the sale of the minerals

(after deducting extraction costs) into income and

depletion, with depletion determined as the amount

necessary to create a fund sufficient to yield an annual

amount equal to the income portion, beginning after

the mineral reserve is exhausted Both methods have

advantages and disadvantages, and both have been

used for calculating the net national products of

indi-vidual countries

Measuring Sustainable Growth

An important use of RA is to determine whether a

veloping country is following a path of sustainable

de-velopment or is depleting its natural resource

capi-tal—including its minerals, forests, and soil—under

conditions that threaten the economy’s ability to

main-tain its current level of consumption If a country

saves and invests in other industries an amount equal

to the value of the depletion of its natural resource capital, mineral exhaustion may not be accompanied

by a decline in economic growth RA also provides a more accurate measure of a country’s growth rate, be-cause without taking account of natural resource de-pletion and degradation, the growth rate measured

by SNA may overstate the rate that the country can sustain

Raymond F Mikesell

Further Reading Ahmad, Yusuf J., Salah El Serafy, and Ernst Lutz, eds

Environmental Accounting for Sustainable Develop-ment Washington, D.C.: World Bank, 1989.

Bartelmus, Peter, and Eberhard K Seifert, eds Green

Accounting Burlington, Vt.: Ashgate, 2003.

Hecht, Joy E National Environmental Accounting:

Bridging the Gap Between Ecology and Economy

Wash-ington, D.C.: Resources for the Future, 2005 Lange, Glenn-Marie “Environmental and Resource

Accounting.” In Handbook of Sustainable

Develop-ment, edited by Giles Atkinson, Simon Dietz, and

Eric Neumayer Northampton, Mass.: Edward Elgar, 2007

Lutz, Ernst, ed Toward Improved Accounting for the

Envi-ronment Washington, D.C.: World Bank, 1993.

Mikesell, Raymond F Economic Development and the

En-vironment: A Comparison of Sustainable Development with Conventional Development Economics New York:

Mansell, 1992

Perrings, Charles, and Jeffrey R Vincent, eds Natural

Resource Accounting and Economic Development: The-ory and Practice Northhampton, Mass.: Edward

Elgar, 2003

Repetto, Robert, et al Wasting Assets: Natural Resources

in the National Income Accounts Washington, D.C.:

World Resources Institute, 1989

Rogers, Peter P “Natural Resource Accounting.” In

An Introduction to Sustainable Development, edited by

Stephen J Banta, David Sheniak, and Anita Feleo Cambridge, Mass.: Continuing Education Division, Harvard University, 2006

See also: Capitalism and resource exploitation; De-forestation; Developing countries; Ecosystem ser-vices; Energy economics; Environmental degradation, resource exploitation and; Health, resource exploita-tion and; Renewable and nonrenewable resources; United Nations Environment Programme

Trang 10

Resource Conservation and

Recovery Act

Categories: Laws and conventions; government

and resources

Date: Passed October 21, 1976

The Resource Conservation and Recovery Act of 1976

(RCRA) is a comprehensive U.S environmental law

that regulates nonhazardous solid waste and

hazard-ous waste It encourages recycling and reuse and

man-dates that hazardous waste be managed in an

envir-onmentally responsible manner from the time it is

generated until it is disposed of.

Background

After World War II, the United States experienced

rapid economic and industrial expansion With this

growth came a significant increase in the generation

and accumulation of wastes, both hazardous and

non-hazardous As waste management practices failed to

keep pace with waste production, much of the waste

entered the environment, where it posed a threat to

ecosystems and human health

In 1965, Congress passed the Solid Waste Disposal

Act (SWDA), which set safety standards for landfills

and established a framework for managing trash

posal Over the following decade, however, waste

dis-posal problems continued to mount The amount of

trash generated by individuals rose, as did the

quan-tity of toxic by-products produced by the manufacture

of synthetic chemicals A 1970 amendment, the

Re-source Recovery Act, sought to bring the problem

un-der control by setting national disposal criteria for

hazardous waste, establishing guidelines for sanitary

landfill and incineration facility operation, and

en-couraging programs for reclamation of materials and

energy from solid waste

By the mid-1970’s, it was clear that the waste

man-agement provisions of the amended SWDA remained

insufficient to meet the challenges posed by the

stag-gering quantities of solid and hazardous waste that

municipalities and industries across the nation were

generating Congress addressed SWDA’s deficiencies

with the October 21, 1976, passage of a more

compre-hensive amendment, known as RCRA

RCRA was so thorough an overhaul of SWDA that

amendments to SWDA passed after 1976 are generally

regarded as part of RCRA Among the more

signifi-cant of these amendments are the Medical Waste Tracking Act of 1988 (MWTA), the Hazardous and Solid Waste Amendments of 1984 (HSWA), the Fed-eral Facilities Compliance Act of 1992 (FFCA), and the Land Disposal Program Flexibility Act of 1996 (LDPFA) MWTA followed highly publicized incidents

in 1987, in which syringes and other medical waste washed up on public beaches in the Northeast HSWA passed in response to public concern regarding haz-ardous waste disposal in substandard incinerators and landfills FFCA was enacted in the early post-Cold War years to require RCRA compliance from Department

of Defense and Department of Energy sites and other federal facilities that had previously claimed sovereign immunity from environmental regulations LDPFA, designed to eliminate regulatory redundancy and re-duce compliance costs associated with the disposal of certain low-risk wastes, was part of the Reinventing Environmental Regulation initiative, a commonsense legal-reform effort during Bill Clinton’s presidency

Provisions RCRA is a groundbreaking environmental law in that

it takes a “cradle-to-grave” approach to pollution con-trol It seeks not only to mitigate pollutant emissions but also to minimize how much pollution is gener-ated in the first place RCRA requires that, once gen-erated, hazardous wastes be managed, tracked, and ultimately disposed of, all in an environmentally re-sponsible manner RCRA encourages measures such as source reduction, recycling, and conservation of en-ergy and natural resources The act sets forth statutory and regulatory requirements and liability for owners and operators of facilities that fail to meet its require-ments The U.S Environmental Protection Agency (EPA) Office of Resource Conservation and Recovery (known prior to 2009 as the Office of Solid Waste) has primary responsibility for implementing RCRA RCRA provisions address three interrelated waste-management concerns: nonhazardous solid waste (Subtitle D), hazardous solid waste (Subtitle C), and underground storage tanks (Subtitle I) A fourth pro-gram focusing on medical-waste management, de-scribed in Subtitle J, is no longer in effect

Subtitle D of RCRA provides a regulatory frame-work for the nation’s solid-waste management It pro-hibits open dumping of solid wastes and establishes minimum standards for landfill location, operation (including daily cover requirements), design (includ-ing liners and leachate collection systems),

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