You can easily make a sechi disk to measure water turbity -- an indication of water quality in terms of its clarity.

On a besoin de...
  • a 20cm-diameter, 6mm-thick Plexiglas disk with a hole in the middle (this may be cut from a square sheet of Plexiglas)
  • metal disk with a hole in the middle (to weigh down Secchi disk)
  • an eyebolt with nuts and washers to fit it
  • rope or cord- try to avoid cotton, as it stretches
  • waterproof black and white paint
  • Lisez-en plus au sujet de cette activité au biograph de David Schindler...

    ce qui à faire

     Instructions and materials can be found at the following places:



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