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Chemical control: use of insecticides to kill insects that damage food crops. This also harms the environment and gets washed into rivers, dams and seas, negatively impacting onfood chains.

Biological control: use natural predators to eradicate (get rid of) of pests that feed and damage on food crops. This ensures that the useful plants and animals as well as the soilas a natural resource is not damaged.

Deforestation: removal of natural forests. This destroys biodiversity, and also removes plants which help to decrease the carbon dioxide burden.

Acid Rain : Burning fossil fuels may also produce sulphur dioxide and nitrogen oxide gases. These gases rise up in the atmosphere from factories, power stations andvehicles and dissolve in the water in clouds forming acid rain. Acid rain can damage trees directly.If the water in rivers and lakes becomes too acidic,plants and animals cannot survive. Acid rain also damages buildings

Eutrophication: Pollution of water by fertilisers may cause eutrophication. The fertiliser causes rapid growth of aquatic plants such as algae. The increased amount ofalgae on the surface of the water blocks out sunlight, preventing plants at the bottom of river from photosynthesising. These plants die and begin todecompose. Micro-organisms feed and decompose dead plants using up oxygen in the water. Fish and other aquatic organisms die due to oxygen shortage.

Sewage pollutes the sea and fresh water, unless it is treated properly.This is a health hazard, but it also upsets the balance of organisms living in the water.Untreated sewage provides food for micro-organisms and causes eutrophication.

Toxic chemicals are released from industrial plants and by farmers. These can pollute the land and water.Some toxins e.g. DDT can accumulate along food chains until the toppredator has very high, often lethal, amounts in its body.DDT is carcinogenic (cancer causing)

Definitions and terms

Pollution: an undesirable change in the natural resources due to negative influences of human activities.

Thermal pollution: hot waste water released by industries and mining into rivers and lakes increases temperature of water ‘driving’ out oxygen killing fishand other aquatic life.

Contamination: not fit for human consumption as it contains bacteria

Sewage: waste water containing faeces

Flora: refers to all plant life

Fauna: refers to all animal life


The greenhouse effect

To see how greenhouse gases affect the climate try this simulation from PhET. Explore the atmosphere during the ice age and today. What happens when you addclouds? Change the greenhouse gas concentration and see how the temperature changes. Then compare to the effect of glass panes. Zoom in and see how lightinteracts with molecules. Do all atmospheric gases contribute to the greenhouse effect?

Phet: The Greenhouse Effect: http://phet.colorado.edu/en/simulation/greenhouse

Human’s influence on greenhouse gas concentrations

Take a look at http://www.breathingearth.net/ to see how much CO2 is currently been released into the atmosphere.

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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why and for what was five kingdom of classification of organisms introduced
give the ans as fast as possible
Comment on the ozone depletion over the period of 1982 to 1996
Mpho Reply

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Source:  OpenStax, Siyavula: life sciences grade 10. OpenStax CNX. Apr 11, 2012 Download for free at http://cnx.org/content/col11410/1.3
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