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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

Activities

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

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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.
Bharti
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
Daniel
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Good
why and for what was five kingdom of classification of organisms introduced
SUBHIKSHA Reply
give the ans as fast as possible
SUBHIKSHA
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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