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A catchment area

  • The sizes of catchment areas vary greatly. Most of South Africa's large storage dams get their water from such mountain catchment areas.

There is a close relationship between soil conservation and the use of water from catchment areas. Dense vegetation prevents soil erosion to a large extent. Where the vegetation is removed, especially on steep slopes, rainwater flows fast and the danger that a flash flood can occur is increased. This happened in 1981, when a flood caused serious damage to Laingsburg. When fertile topsoil is removed, storage dams and river mouths become silted up as the soil is deposited in these places.

The fynbos kingdom, which is unique to the Western Cape, is threatened by urbanisation, planting of forests and deforestation in the catchment areas. It is important to protect catchment areas. Most of the plants in the fynbos kingdom are small, hardy and spiky to reduce loss of water during the dry summer months. Some well-known plants from this kingdom are the Ericas, Proteas and the Restios, which are grass-like members of the reed family.

  • Invader plants like pine trees have been planted in many places in the catchment areas. Amongst other things, pine trees, together with hakea and Australian acacia species, disturb the natural balance of the river ecosystems of the Western Cape.

FACTORS THAT AFFECT THE QUALITY OF THE WATER IN THE RIVERS.

  • All of us must share the responsibility of using water resources responsibly. Every person can make a contribution by becoming involved in our own communities. In this way we can also assist governing bodies and make it easier for them to function.
  • All of us need inland water for personal use and we must remember that overpopulation and mismanagement of our limited resources is not a new problem. The Greek philosopher Plato was already complaining about environmental degradation two thousand years ago.
  • POLLUTION refers to any substance that has a harmful effect on the natural environment. The pollutants might be in the atmosphere, or may occur in water that flows through any part of the catchment area. Pollutants may be very difficult to identify and control.
  • ARTIFICIAL FERTILISERS are used by farmers to ensure bigger harvests. These nutrients are washed away in rivers. This encourages the growth of algae, which reduces the amount of oxygen in the water.
  • RUBBISH like tins and plastic bags block up small streams.
  • SEWERAGE water is rich in organic substances and nutrients that also reduce oxygen levels in the water during decomposition. This destroys many species of life that occur in rivers.
  • HEAT POLLUTION is caused by pumping warm water into rivers and lakes.
  • TOXIC CHEMICALS and heavy metals build up in living tissue and increase over time. This inevitably leads to the death of numbers of plants and animals.
  • SOLID WASTE MATERIALS like soil particles from eroded land, mining activities, coal, dust and builder's rubble also flow along down streams. This suffocates water creatures and their eggs, block up the gills of fish and buries food sources.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
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
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
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
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
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
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Source:  OpenStax, Natural sciences grade 6. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11079/1.1
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