biology folio form 4 chapter 9 endangered ecosystem (autosaved)
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BIOLOGY FOLIO
CHAPTER 8:ENDANGERED ECOSYSTEM
NAME : MEGAT AHMAD KAMARUL BIN MEGAT
ZULKIFLI
CLASS : 402
TEACHER : MISS ZALILI
SCHOOL : MRSM PENGKALAN HULU
NO CONTENT PAG
E
I. Introduction
II. Objective
III. Human Activities That Endanger An
Ecosystem
i. Cause
ii. Source
IV. Greenhouse Effects And The Thinning Of
Ozone layer
V. Steps To Maintain stable Environment
VI. Conclusion
VII. Reference
CONTENT
INTRODUCTION
A healthy yet picturesque environment is always a significant dream to others . However numerous negative impact from un responsible human activities has
greatly affect our dream environment . It has not only cause in balance in environment but also causes various environmental problem besides endangering the ecosystem. The only way for us and the future generation to have a sense of peace mind living in the dream picturesque environment is mainly by planning development activities with great care which will possibly not affecting the environment at all. After all environment is our main home. So the environment should be preserved starting from now onwards so that the future generation will be able to feel the environment which we are experiencing now .
THE REASON FOR THE PAPERWORK IS BEING DONE IS DUE TO SEVERAL OBJECTIVES AS STATED BELOW :
To in still awareness among human about the importance of the preservation and the conservation of the ecosystem .
To sensitize humans on various type of negative effects of their activities towards the environment .
To raise the efforts of creating a convenient , safer yet conducive environment for ourselves and the future generations .
To deduce the time for the depletion and the destruction of the environment due to the environmental problems caused by human beings .
APPRECIATION
I , Megat Ahmad Kamarul Bin Megat Zulkifli from 402 would like those who have been indirectly or directly involved in the making of this folio titled “ENDANGERED ECOSYSTEM” . Ministry Of Education’s effort in organizing the making of this folio is highly appreciated in a way of increasing students understanding in biology .Hence, not only increasing student’s level of understanding , but also increasing the value of studying biology as it is related to our living .
By doing this folio, it does not only increase my understanding towards biology ,also it makes me grow enthusiastic towards the
intriguing subject, biology .I have now completed a paperwork on the topic “ENDANGERED ECOSYSTEM” based on the last chapter in the form 4 syllabus.
Nevertheless ,I felt relief and grateful upon having such fabulous companion and references who were my biology teacher Miss Zalili ,my parents ,helpful friends also siblings .I was really thankful to those who have helped me out ,being supportive yet helpful especially in providing extra information on the topic which is given to in the making of this folio .Without their help surely I will not be able to make this folio as a satisfying piece.
Human activities that threaten the ecosystem
The worlds population might reach to 10 billions in the next fifty years .Hence, when there are increments in the number of the worlds population , it generally means that there is an increasing demand for shelter, food, medicine, transport and raw materials .
Today, due to expectation of modern living and industrial revolution, the world has to confront the destruction of forests to build more houses, to being use as plantation areas and build roads, just to fulfil humans needs .
1.0 - HUMAN ACTIVITIES THAT ENDANGER THE ECOSYSTEM
Unplanned developments and mismanagement of ecosystem give rise to vast amounts of environmental crisis. Among those environmental problems are greenhouse effect, global warming, pollution, soil erosion, landslide, flash flood and ozone depletion .
The human activities that we are talking about are like agriculture, burning or combustion, industrialization, urbanization and last but not least, deforestation.
Large agriculture of forests are cleared for extracting timber of fuel wood , agriculture needs, and for the sake of urbanization. The impacts are enormous and outrageous. Let see what are the drawbacks of deforestation .
1. LANDSLIDES Soil erosion is blocked. Thus, water flows inland and causes flash
flood and landslides. When it rains for a long time especially during rainy season, the
top layer of soil loosens and slides down , thus causing landslides.
DEFORESTATION
2. SOIL EROSION leaning of trees causes the loss of tree leaves that protect the soil
from a massive impulsive force of heavy raindrops and also causes the loss of tree roots that hold the soil in place
The wide exposure to the raindrops forces, give arise to soil erosion. Here ,the top layer of soil is easily being washed away by heavy rainfall. The eroded soil, is then, deposited in rivers or streams.
3. FLASH FLOOD During heavy rains, rainwater flows harshly into rivers because
there is a non-existence of retention of water by plant roots as well as proper water catchments areas
Due to silting in the rivers, the water flow is blocked. Thus, water flows inland and causes flash floods in low areas.
In addition, soil erosion contributes in the depletion of minerals in the soil, causing the land trouble to be used as a place of cultivation.
4. FARMING
In order to full fill the demands of todays food supplement, large areas of lands have been used and will be used for farming purposes.
Excessive use of land for farming and stock rearing lead to infertile land and may expose the soil to erosion by wind or heavy rainfalls.
Inorganic fertilizers usage in farming also results to eutrophication.
5. URBANISATION
Industrialisation give off industrial waste and heated waste water causing water pollution and thermal pollution.
Toxic gases released by industries contribute to a major concerning problem ; air pollution.
What Is A Greenhouse Effects?
The greenhouse effect is a process by which radioactive energy leaving a planetary surface is absorbed by some atmospheric gases, called greenhouse gases. They transfer this energy to other components of the atmosphere, and it is re-radiated in all directions, including back down towards the surface. This transfers energy to the surface and lower atmosphere, so the temperature there is higher than it would be if direct heating by solar radiation were the only
3.0 THE GREENHOUSE EFFECTS
warming mechanism. This mechanism is fundamentally different from that of an actual greenhouse, which works by isolating warm air inside the structure so that heat is not lost by convection.
Who Discovered the Greenhouse Effects?
The greenhouse effect was discovered by Joseph Fourier in 1824, first reliably experimented on by John Tyndall in 1858, and first reported quantitatively by S vante Arrhenius in 1896.If an ideal thermally conductive blackbody was the same distance from the Sun as the Earth, it would have an expected blackbody temperature of 5.3 °C. However, since the Earth reflects about 30% (or 28%) of the incoming sunlight, the planet's actual blackbody temperature is about -18 or -19 °C, about 33°C below the actual surface temperature of about14 °C or 15 °C.
The mechanism that produces this difference between the actual temperature and the blackbody temperature is due to the atmosphere and is known as the greenhouse effect
Global warming, a recent warming of the Earth's surface and lower atmosphere, is believed to be the result of a strengthening of the greenhouse effect mostly due to human-produced increases in atmospheric greenhouse gases.
The ozone layer protects the Earth from the ultraviolet rays sent down by the sun. If the ozone layer is depleted by human action, the effects on the planet could be catastrophic. Ozone is present in the stratosphere. The stratosphere reaches 30 miles above the Earth, and at the very top it contains ozone. The sun’s rays are absorbed by the ozone in the stratosphere and thus do not reach the Earth. Ozone is a bluish gas that is formed by three atoms of oxygen. The form of oxygen that humans breathe in consists of two oxygen atoms, 2.When
4.0 THE THINNING OF THE OZONE LAYER
found on the surface of the planet, ozone is considered a dangerous pollutant and is one substance responsible for producing the greenhouse effect.
The highest regions of the stratosphere contain about 90% of all
In recent years, the ozone layer has been the subject of much discussion. And rightly so, because the ozone layer protects both plant and animal life on the planet .The fact that the ozone layer was being depleted was discovered in themid-1980s. The main cause of this is the release of CFCs (chlorofluorocarbons) .Antarctica was an early victim of ozone destruction. A massive hole in the ozone layer right above Antarctica now threatens not only that continent, but many others that could be the victims of Antarctica's melting icecaps. In the future, the ozone problem will have to be solved so that the protective layer can be conserved.
5.1 Managing development activities to ensure a balanced ecosystem.
1. Enforcement of the environmental laws Environment quality act, 1974 Controls and prevents the pollution of the environment Controls the type of licensing, contentand quality of environment Tests and examines the samples of substances and gas from industries Natural forestry act, 1984
-Aims at protecting and preserving our forests and wildlife Pesticides act, 1974
5.0 THE IMPORTANCE OF PROPER MANAGEMENT OF DEVELOPEMENTACTIVITIES AND ECOSYSTEM
-Aims at controlling the use of pesticides Protection of wildlife act, 1972
-Aims at protecting wildlife animals, birds and plants Fisheries act, 1985
-Aims at controlling marine pollution
2. Use Of Technology
Use modern equipment and chemicals to control oil spills. Recycle rubbish. To look for methods to do research. Change organic rubbish to biogas. Use less polluting and clean fuels in motor vehicles. Control and treat the toxic and dangerous waste before disposing.
3. Preservation And Conservation Of The Ecosystem
Force the development companies to replant the forest trees after deforestation.
Remaining the mangrove swamps area so that the ecosystem is protected. Restore the mining and used land for agriculture. Put effort in rivers cleaning to ensure there is sufficient supply of water in
future) Practice of biological control. A method of controlling the animal pests by using natural predators
instead of using chemical substances. Factors to choose the animals predators.
4. Biological Control
Pesticides are expensive and toxic to non-pest,while pests may build up stronger resistance to the pesticides used.Pesticide also contributes water and air pollution
Biological control is an alternative method to control pest.It involves the use of the pest’s natural predator to keep the population of the pest at a minimum level.
Female overfly is used to control the population of aphids which suck the nutrient of wheat plants
5. Use of renewable energy
Renewable enery is an energy that occurs naturally and is inexhaustible. It does not contribute to any type of pollution.
Examples are solar energy,wind energy and hydroelectric.
The effects of unplanned development and mismanagement of the ecosystem can lead to damaging consequences such as soil erosion, flash floods, landslides, eutrophication ,pollution global warming, ozone depletion, climatic changes and loss of biodiversity. There are four types of pollution which are air ,water, thermal, and noise pollution. Greenhouse gases released by various human activities can trap heat in the atmosphere and raise the Earth’s average temperature. Such an overall rise in the Earth’s temperature can leads to global warming. The thinning of ozone
Conclusion
layer is mainly due to the accumulation of chloroflurocarbon (CFCs) in the atmosphere. Sustainable development must take into consideration of proper management of the ecosystem to ensure a balance of nature is maintained.
Biology Form 4 Text Book. Success (Oxford Fajar) Biology < 2012 edition > reference books.
REFERENCES
2.1 Air pollution
Air pollution is the introduction of chemicals, particulate matter,
or biological materials
that cause harm or discomfort to humans or other living organisms, or
damages the natural
environment into the atmosphere.
The atmosphere is a complex dynamic natural gaseous system that
is essential to support life on planet Earth. Stratospheric ozone depletion
due to air pollution has long been recognized as a threat to human health
as well as to the Earth's ecosystems.
Air pollution from World War II production
Pollutants
An air pollutant is known as a substance in the air that can cause harm to
humans and the
environment. Pollutants can be in the form of solid particles, liquid
droplets, or gases. In addition,they may be natural or man-made.
Pollutants can be classified as either primary or secondary. Usually,
primary pollutants aresubstances directly emitted from a process, such as
ash from a volcanic eruption, the carbon
monoxide gas from a motor vehicle exhaust or sulfur dioxide released
from factories.Secondary pollutants are not emitted directly. Rather, they
form in the air when primary pollutantsreact or interact. An important
example of a secondary pollutant is ground level ozone— one of the
many secondary pollutants that make up photochemical smog. Note that
some pollutants may be both primary and secondary: that is, they are
both emitted directly and formed from other primary pollutants.About 4
percent of deaths can be attributed to air pollution, according to the
Environmental Science Engineering Program at the Harvard School of
Public Health.
causes and effects of air pollution: (1) greenhouse effect, (2) particulate contamination,
(3) increased UV
radiation, (4) acid rain, (5) increased ozone concentration, (6) increased levels of
nitrogen oxides
Major primary pollutants produced by human activity include:
Sulphur oxides (SOx) - especially sulfur dioxide, a chemical
compound with the formula SO2. SO2 is produced by volcanoes and
in various industrial processes. Since coal and petroleum often
contain sulfur compounds, their combustion generates sulfur
dioxide. Further oxidation of SO2, usually in the presence of a
catalyst such as NO2, forms H2SO4, and thus acid rain. This is one
of the causes for concern over the environmental impact of the use
of these fuels as power sources.
Nitrogen oxides (NOx) - especially nitrogen dioxide are emitted from
high temperature combustion. Can be seen as the brown haze
dome above orpl ume downwind of cities.
Nitrogen dioxide is the chemical compound with the formula NO2.
It is one of the several nitrogen oxides. This reddish-brown toxic gas has
a characteristic sharp, biting odor.NO2 is one of the most prominent air
pollutants.
Carbon monoxide - is a colourless, odourless, non-irritating but very
poisonous gas. It is a product by incomplete combustion of fuel such
as natural gas, coal or wood. Vehicular
exhaust is a major source of carbon monoxide.
Carbon dioxide (CO2) - a greenhouse gas emitted from combustion
but is also a gas vital to living organisms. It is a natural gas in the
atmosphere.
Volatile organic compounds - VOCs are an important outdoor air
pollutant. In this field they are often divided into the separate
categories of methane (CH4) and non-methane (NMVOCs). Methane
is an extremely efficient greenhouse gas which contributes to
enhanced global warming. Other hydrocarbon VOCs are also significant
greenhouse gases via their role in creating ozone and in prolonging the
life of methane in the atmosphere, although the effect varies depending
on local air quality. Within the NMVOCs, the aromatic compounds
benzene, toluene and xylene are suspect carcinogens and may lead to
leukemia through prolonged exposure. 1,3-butadiene is another
dangerous compound which is often associated with industrial uses.
Particulate matter - Particulates, alternatively referred to as
particulate matter (PM) or fine particles, are tiny particles of solid or
liquid suspended in a gas. In contrast, aerosol refers to particles and
the gas together. Sources of particulate matter can be man made or
natural. Some particulates occur naturally, originating from
volcanoes, dust storms, forest and grassland fires, living vegetation,
and sea spray. Human activities, such as the burning of fossil fuels
in vehicles, power plants and various industrial processes also
generate significant amounts of aerosols. Averaged over the globe,
anthropogenic aerosols—those made by human activities—currently
account for about 10 percent of the total amount of aerosols in our
atmosphere. Increased levels of fine particles in the air are linked to
health hazards such as heart disease, altered lung function and lung
cancer
Minor air pollutants include:
A large number of minor hazardous air pollutants.
A variety of persistent organic pollutants, which can attach to
particulate matter.
Persistent organic pollutants (POPs) are organic compounds that are
resistant to environmental
degradation through chemical, biological, and photolytic processes.
Because of this, they have been observed to persist in the environment,
to be capable of long-range transport, bioaccumulate in human and
animal tissue, biomagnify in food chains, and to have potential significant
impacts on human health and the environment.
Natural sources
Effects
Air pollution is responsible for major health effects.Every year, the health of
countless people is ruined or endangered by air pollution.
Many different chemicals in the air affect the human body in negative
ways.Just how sick people will get depends on what chemicals they are exposed
to, in what concentrations, and for how long.
Studies have estimated that the number of people killed annually in the US
alone could be over 50,000.
Older people are highly vulnerable to diseases induced by air
pollution.Those with heart or lung disorders are under additional risk.Children
and infants are also at serious risk. Because people are exposed to so many
potentially dangerous pollutants, it is often hard to know exactly which
pollutants are responsible for causing sickness.Also, because a mixture of
different pollutants can intensify sickness, it is often difficult to isolate those
pollutants that are at fault.
Many diseases could be caused by air pollution without their becoming
apparent for a long time.Diseases such as bronchitis, lung cancer, and heart
disease may all eventually appear in people exposed to air pollution.
Air pollutants such as ozone, nitrogen oxides, and sulfur dioxide also have
harmful effects on Natural eco systems.They can kill plants and trees by
destroying their leaves, and can kill animals, especially fish in highly polluted
rivers.
ACID RAIN
Acid rain is a result of air pollution. When any type of fuel is burnt, lots of different chemicals are produced. The smoke that comes from a fire or the fumes that come out of a car exhaust don't just contain the sooty grey particles
that you can see - they also contains lots of invisible gases that can be even more harmful to our environment. Power stations, factories and cars all burn fuels and therefore they all produce polluting gases. Some of these gases (especially nitrogen oxides and sulphur dioxide) react with the tiny droplets of water in clouds to form sulphuric and nitric acids. The rain from these clouds then falls as very weak acid - which is why it is known as "acid rain".How acidic is acid rain? Acidity is measured using a scale called the pH scale. This scale goes from 0 to 14. 0 is the most acidic and 14 is the most alkaline (opposite of acidic). Something with a pH value of 7, we call neutral, this means that it is neither acidic nor alkaline.Very strong acids will burn if they touch your skin and can even destroy metals. Acid rain is much, much weaker than this, never acidic enough to burn your skin.
Rain is always slightly acidic because it mixes with naturally occurring oxides in the air. Unpolluted rain would have a pH value of between 5 and 6. When the air becomes more polluted with nitrogen oxides and sulphur dioxide the acidity can increase to a pH value of 4. Some rain has even been recorded as being pH2. Vinegar has a pH value of 2.2 and lemon juice has a value of pH2.3. Even the strongest recorded acid rain is only about as acidic as lemon juice or vinegar and we know that these don't harm us - so why do we worry about acid rain?
The Effects of Acid Rain
Acid rain can be carried great distances in the atmosphere, not just between countries but also from continent to continent. The acid can also take the form of snow, mists and dry dusts. The rain sometimes falls many miles from the source of pollution but wherever it falls it can have a serious effect on soil, trees, buildings and water.Forests all over the world are dying, fish are dying. In Scandinavia there are dead lakes, which are crystal clear and contain no living creatures or plant life. Many of Britain's freshwater fish are threatened, there have been reports of
deformed fish being hatched. This leads to fish-eating birds and animals being affected also. Is acid rain responsible for all this? Scientists have been doing a lot of research into how acid rain affects the environment.
ForestsIt is thought that acid rain can cause trees to grow more slowly or even to die but scientists have found that it is not the only cause. The same amount of acid rain seems to have more effect in some areas than it does in others.As acid rain falls on a forest it trickles through the leaves of the trees and runs down into the soil below. Some of it finds its way into streams and then on into rivers and lakes. Some types of soil can help to neutralise the acid - they have what is called a "buffering capacity".Other soils are already slightly acidic and these are particularly susceptible to the effects of acid rain.Acid rain can effect trees in several different ways, it may:• dissolve and wash away the nutrients and minerals in the soil which help the trees to grow.• cause the release of harmful substances such as aluminium into the soil.• wear away the waxy protective coating of leaves, damaging them and preventing them from being able to photosynthesise properly.
2.2 Water Pollution
Water pollution is the contamination ofwater bodies (e.g.lakes,ri ve
rs,oceans andgro undwater). Water pollution affects plants and organisms living
in these bodies of water; and, in almost all cases the effect is damaging not only
to individualspecie s and populations, but also to the natural biological
communities.
Water pollution occurs whenpollutants are discharged directly or indirectly
into water bodies
without adequatet r e atm ent to remove harmful compounds.
Pollutants
Water pollution is usually caused by human activities. Different human sources
add to the
pollution of water. There are two sorts of sources, point and nonpoint
sources.Point sources discharge pollutants at specific locations through
pipelines or sewers into the surface water. Nonpoint sources are sources that
cannot be traced to a single site of discharge.
Pb poisoning is another serious source of environmental pollution which
causes water pollution. Pb poisoning is characterized by CNS damage, anaemia
and deposition of Pb in bones and teeth. The major sources of this pollutant are
paint manufacturing industries/factories, lead smelting works; petrol engines
discharged inorganic Pb salts, metallic Pb and organic Pb respectively. Pb
(C2H4)4 – is used as an anti knock in petrol engines and is a pollutant. The
anaemia caused by Pb is due to inhibition of haem biosynthesis. Inorganic Pb
inhibits aminolaevulinic acid dehydratase and ferrochetalase (haem synthetase)
which catalyses the formation of the pyrrole porphobilinogen and incorporation
of Fe 2+ into protoporphyrin IX respectively.
There are a lot of types of water pollution. One of them is caused by toxic
substances. This is when someone dumps out a chemical pollutant into water.
One of the greatest contributors to toxic pollution is a factory compound.
Once water is contaminated, it is difficult, expensive, and sometimes
impossible to remove pollutants. Technologies to remove contaminants from
groundwater are air stripping, granular activated carbon, and advanced
oxidation. Air stripping involves pumping out the contaminated
water, then heating it to evaporate the contaminant. The cleaned water is
reinjected into the ground. Pumping out contaminated water and absorbing the
pollutant on activated charcoal can remove less volatile compounds.
Pollutants in water include a wide spectrum of chemicals, pathogens,
and physical chemistry or sensory changes.Many of the chemical substances
are toxic. Pathogens can produce waterborne diseases in either human or
animal hosts. Alteration of water's physical chemistry include acidity,
electrical conductivity, temperature, and eutrophication. Eutrophication is
the fertilisation of surface water by nutrients that were previously scarce. Even
many of the municipal water supplies in developed countries can present health
risks.
One class of water pollutants are nutrients; they are water-soluble nitrates
and phosphates that cause excessive growth of algae and other water plants,
which deplete the water's oxygen supply. This kills fish and, when found in
drinking water, can kill young children.
Heat is a water pollutant—increased water temperatures result in the
deaths of many aquatic organisms. These increases in temperature are most
often caused by discharges of cooling water by factories and power plants.
At industrial sites, chemical spills that contain toxic substances, smoke
stacks that spew emissions and uncovered or unprotected outdoor storage or
waste areas can contribute pollutants to storm water runoff.
Sources
The specific contaminants leading to pollution in water include a wide spectrum
of chemicals, pathogens, and physical or sensory changes such as elevated
temperature and discoloration. While many of the chemicals and substances that
are regulated may be naturally occurring (calcium,so di um,iron,m angane se,
etc.) theconcentration is often the key in determining what is a natural
component of water, and what is a contaminant.
Oxygen-depleting substances may be natural materials, such
as plant matter (e.g. leaves and grass) as well as man-made chemicals. Other
natural and anthropogenic substances may cause turbidity (cloudiness) which
blocks light and disrupts plant growth, and clogs the gills of some fish species.
Many of the chemical substances are toxic. Pathogens can
produce waterborne diseases in either human or animal hosts. Alteration of
water's physical chemistry includes acidity (change in pH), electrical
conductivity, temperature, and eutrophication. Eutrophication is an increase in
the concentration of chemical nutrients in an ecosystem to an extent that
increases in the primary productivity of the ecosystem. Depending on the degree
of eutrophication, subsequent negative environmental effects such
asanoxia (oxygen depletion) and severe reductions in water quality may occur,
affecting fish and other animal populations.
2.3 Thermal Pollution
Thermal pollution is the degradation of water quality by any process that
changes ambient water temperature.
A common cause of thermal pollution is the use of water as aco o l
ant by power plants and
industrial manufacturers. When water used as a coolant is returned to the natural
environment at a higher temperature, the change in temperature (a)
decreasesoxy gen supply, and (b) affects ecosystemco m po sitio n. Urban
runoff--stormwater discharged to surface waters from roadsand parking lots--
can also be a source of elevated water temperatures.
When a power plant first opens or shuts down for repair or other causes, fish
and other organisms adapted to particular temperature range can be killed by the
abrupt rise in water temperature known as 'thermal shock'.
Pollutant
Sources
The major sources of thermal pollution are electric power plants and industrial
factories. In most electric power plants, heat is produced when coal, oil, or
natural gas is burned or nuclear fuels undergo fission to release huge amounts of
energy. This heat turns water to steam, which in turn spins turbines to produce
electricity. After doing its work, the spent steam must be cooled and condensed
back into water. To condense the steam, cool water is brought into the plant and
circulated next to the hot steam. In this process, the water used for cooling
warms 5 to 10 Celsius degrees (9 to 18 Fahrenheit degrees), after which it may
be dumped back into the lake, river, or ocean from which it came. Similarly,
factories contribute to thermal pollution when they dump water used to cool
their machinery.
The second type of thermal pollution is much more widespread. Streams and
small lakes are naturally kept cool by trees and other tall plants that block
sunlight. People often remove this shading vegetation in order to harvest the
wood in the trees, to make room for crops, or to construct buildings, roads, and
other structures. Left unshaded, the water warms by as much as 10 Celsius
degrees (18 Fahrenheit degrees). In a similar manner, grazing sheep and cattle
can strip streamsides of low vegetation, including young trees. Even the
removal of vegetation far away from a stream or lake can contribute to thermal
pollution by speeding up the erosion of soil into the water, making it muddy.
Muddy water absorbs more energy from the sun than clear water does, resulting
in further heating. Finally, water running off of artificial surfaces, such as
streets, parking lots, and roofs, is warmer than water running off vegetated land
and, thus, contributes to thermal pollution.
Effects
Elevated temperature typically decreases the level of dissolved oxygen (DO) in
water. The
decrease in levels of DO can harm aquatic animals such as fish,am phi bi a
ns andco pepo ds. Thermal pollution may also increase them etabo lic rate of
aquatic animals, asenzym e activity, resulting in these organisms consuming
more food in a shorter time than if their environment were not changed. An
increased metabolic rate may result in fewer resources; the more adapted
organisms moving in may have an advantage over organisms that are not used
to the warmer temperature. As a result one has the problem of
compromising food chains of the old and new environments. Biodiversity can
be decreased as a result.
It is known that temperature changes of even one to two
degreesCelsius can cause significant changes in organism metabolism and other
adverse cellular biology effects. Principal adverse changes can include
rendering cell walls less permeable to necessaryo smo sis, coagulation of
cellprote ins, and alteration of enzyme metabolism. These cellular level effects
can adversely affectmortality andrepro duction.
Primary producers are affected by warm water because higher water
temperature increases plant growth rates, resulting in a shorter lifespan and
species overpopulation. This can cause an algae bloom which reduces oxygen
levels.
A large increase in temperature can lead to the denaturing of life-supporting
enzymes by breaking downhy dro gen- and disulphide bonds within the
quaternary structure of the enzymes. Decreased enzyme activity in aquatic
organisms can cause problems such as the inability to break downlipids, which
leads tom alnutrition.
In limited cases, warm water has little deleterious effect and may even lead
to improved function of the receiving aquatic ecosystem. This phenomenon is
seen especially in seasonal waters and is known as thermal enrichment. An
extreme case is derived from the aggregational habits of them anatee, which
often uses power plant discharge sites during winter. Projections suggest that
manatee populations would decline upon the removal of these discharges.
2.4 Noise Pollution
Noise pollution(orenvironmental noise) is displeasing human, animal or
machine-created sound that disrupts the activity or balance of human or animal
life. The wordnoise comes from the Latin wordnause as, meaning seasickness.
The source of most outdoor noise worldwide is
mainlyconstruction andtransportatio n
systems, including motor vehicleno ise, aircraft noiseand rail noise. Poor urban
planning may give rise to noise pollution, since side-by-side industrial and
residential buildings can result in noise pollution in the residential area.
Indoor and outdoor noise pollution sources include car alarms, emergency
servicesirens,
mechanical equipment,fi rew or ks, compressed air horns, groundskeeping
equipment, barking dogs, appliances,lighting hum, audio entertainment systems,
electricm egapho nes, and loud people.
Sources
Noise becomes irritating if you're in the comfort of your home and an endless
drone of low
flying airplanes will pass overhead. It causes your blood pressure to rise since
the occurrence can shake your walls and rattle you window panes. On top of
that, you have read so many incidents about how accidents can happen; that by
some stroke of misfortune any one of these planes may accidentally use your
roof as landing pads.
Noise becomes a form of pollution if you're living in the city and the traffic
could bring a lot of cars honking simultaneously as their way of trying to protest
the long
hours they have been waiting in queue. Add the multitudes of pedestrians who'd
rather walk than wait it out in the city traffic, most of them talking
simultaneously,
enough to create a din. Noise in the city can disrupt your sleep, invade your
privacy when you find it hard to carry on with a simple conversation or create
an unpleasant atmosphere for work done at home.
Efects
Human health
Noise health effects are both healthand behavioral in nature. The unwanted
sound is called noise. This unwanted sound can damage physiological and
psychological health. Noise pollution can cause annoyance and aggression,hy
pertension, high stress levels,tinnitus, hearing loss, sleep disturbances, and other
harmful effects.Furthermore, stress and hypertension are the leading causes to
health problems, whereas tinnitus can lead to forgetfulness, severe depression
and at times panic attacks.
Chronic exposure to noise may cause noise-induced hearing loss. Older
males exposed to significant occupational
noise demonstratesignificantly reduced hearing sensitivity than their non-
exposed peers, though differences in hearing sensitivity decrease with time and
the two groups are indistinguishable by age 79.
High noise levels can contribute tocardio v ascular effects and exposure to
moderately high levels during a single eight hour period causes a statistical rise
in blood pressure of five to ten points and an increase instress[3] andv aso
constrictio n leading to the increased blood pressure noted above as well as to
increased incidence of coronary artery disease.
Noise pollution is also a cause of annoyance.
Environment
Noise can have a detrimental effect on animals by causing stress, increasing risk
of death by changing the delicate balance in predator/prey detection and
avoidance, and by interfering with their use of sounds in communication
especially in relation to reproduction and in navigation. Acoustic overexposure
can lead to temporary or permanent loss of hearing.
An impact of noise on animal life is the reduction of usable habitat that
noisy areas may cause, which in the case of endangered species may be part of
the path toe xt inction. Noise pollution has caused the death of certain species of
whales thatbe ache d themselves after being exposed to the loud sound of
military sonar.
Noise also makes species communicate louder, which is called Lombard
vocal response. Scientists and researchers have conducted experiments that
show whales' song length is longer when submarine-detectors are on.If creatures
do not "speak" loud enough, their voice will be masked
by anthropogenic sounds. These unheard voices might be warnings, finding of
prey, or preparations of net-bubbling. When one species begins speaking louder,
it willmask other species' voice, causing the whole ecosystem to eventually
speak louder.
People living in urban environments are more likely to sing at night in
places with high levels of noise pollution during the day, suggesting that they
sing at night because it is quieter, and their message can propagate through the
environment more clearly.The same study showed that daytime noise was a
stronger predictor of nocturnal singing than night-time Light pollution, to which
the phenomenon is often attributed.
Zebra finches become less faithful to their partners when exposed to traffic
noise. This could alter a population's evolutionary trajectory by selecting traits,
sapping resources normally devoted to other activities and thus lead to profound
genetic and evolutionary consequences.
The greenhouse effect is the heating of the surface of a planet or moon due to the presence of an atmosphere containing gases that absorb and emit infrared radiation. Thus, greenhouse gases trap heat within the surface-troposphere system. This mechanism is fundamentally different from that of an actual greenhouse, which works by isolating warm air inside the structure so that heat is not lost by convection. The greenhouse effect was discovered by Joseph Fourier in 1824, first reliably experimented on by John Tyndall in 1858, and first reported quantitatively by Svante Arrhenius in 1896.
The black body temperature of the Earth is 5.5 °C. Since the Earth's surface reflects about 28% of incoming sunlight, the planet's mean temperature would be far lower, about -18 or -19 °C. Along with the added contribution of the
greenhouse effect, it is instead much higher, roughly 14 °C. Global warming, a recent warming of the Earth's surface and lower atmosphere, is believed to be the result of an ‘enhanced greenhouse effect’ mostly due to human-produced increases in atmospheric greenhouse gases. This human induced part is referred to as anthropogenic global warming (AGW).
The Earth receives energy from the Sun mostly in the form of visible light and nearby wavelengths. About 50% of the sun's energy is absorbed at the Earth's surface. Like all bodies with a temperature above absolute zero the Earth's surface radiates energy in the infrared range. Greenhouse gases in the atmosphere absorb most of the infrared radiation emitted by the surface and pass the absorbed heat to other atmospheric gases through molecular collisions. The greenhouse gases also radiate in the infrared range. Radiation is emitted both upward, with part escaping to space, and downward toward Earth's surface. The surface and lower atmosphere are warmed by the part of the energy that is radiated downward, making our life on earth possible.
The distribution of ozone in ionosphere, mesosphere and stratosphere is being depleted. The concentration of ozone is gradually reducing. As the content of ozone is highest in ionosphere and the air itself being very thin, the depletion is negligible in ionosphere. But in mesosphere and stratosphere the air is thicker and ozone content is less. The depletion of ozone is of higher order in these layers. The so called hole in ozone layers simply means that above some continents (specifically Antarctica, Asia and parts of South America) the mesosphere and stratosphere have lost their original level of ozone content.
The depletion of ozone layer is a global phenomena both in terms of cause and effect. The geographical limits of countries are not barriers to either dispersal of
gases in layers of atmosphere or depletion of gases. The causes for depletion may arise in any country. The effects (in terms of depletion) may arise in any other country. The effects (in terms of ozone depletion) need not be exactly above the country causing the depletion.
It is now established that chloroflouro carbon (CFC) chemicals evolved from various refrigerants, coolants and propellants are the primary reasons for depletion of ozone. CFC are a group of chlorine bearing gases of low specific gravity. They rise to stratosphere and mesosphere. Due to ionising solar radiation in these layers, (which is the primary reason for production of ozone) fresh chlorine gas is produced from CFCs. This nascent chlorine gas has the capacity to react with ozone and bring down the level of ozone substantially.
The concept of ozone depletion is new. But study of international ozone trendis being made since 1988, when international ozone commission was established. Extensive ozone assessment facilities were established under International Middle Atmospheric Programme (IMAP) in India to study ozone along with number of other green house gases.