Filtering the water with microorganisms - Marin vuković 8b (2009)

Slide 1: 

FILTERING THE WATER WITH MICROORGANISMS MADE BY: MARIN VUKOVIĆ 8b

Slide 2: 

Water is a privilege because more than 1 billion people in the world have no access to it.

Slide 3: 

At this lake on the outskirts of Berlin an important research project is coming to an end, it's about purifying Berlin drinking water by so called bank filtration.

Slide 4: 

Extraction wells have been dug on the banks of lakes and rivers since 1875.

Slide 5: 

This extraction well is 40 metres deep because very high quality water has been found at these depths for over a century.

Slide 6: 

First the water passes through the fine grain sand on the banks where impurities are filtered.

Slide 7: 

The scientists are trying to find out how the purification happens .

Slide 8: 

With the microscope the experts have discovered entire specialized communities of algae, fungi and bacteria.

Slide 9: 

There are billions of the organisms in a single cubic millimetre and all of them remove contaminants from the water .

Slide 10: 

The monitoring lab at the Berlin waterworks investigates around 200 water drinking samples every day.

Slide 11: 

Again and again the results show how thoroughly the microorganisms among the grains of sand do their work.

Slide 12: 

The microorganisms absorb this cocktail of pollutants while letting the pure water run through the grains of sand.

Slide 13: 

Günther Gunkel discovered that the microorganisms form delicate mesh like structures. These function both as living spaces and as nets that capture some of the contaminants .

Slide 14: 

Only upper layers of sediments contribute to bank filtration.

Slide 15: 

Researchers are hoping that this old purification method can be adapted to meet future challenges.

dictionary : 

dictionary Take for granted – uzeti zdravo za gotovo Faucet – slavina Extraction – crpljenje Impurities – nečistoće Purification – pročišćavanje Sample – uzorak Toxins – otrovi, toksini Mesh – mreža Contaminant – zagađalo, kontaminant Proliferate – razmnožiti se Adapt prilagoditi

Slide 17: 

Extraction wells have been dug on the banks of lakes and rivers since 1875. (Present Perfect Passive) First the water passes through the fine grain sand. (Simple Present) The scientists are trying to find out how the purification happens (Present Continuous) With the microscope the experts have discovered entire specialized communities of algae, fungi and bacteria. (Present Perfect) Günther Gunkel discovered that the microorganisms form delicate mesh like structures. (Simple Past)

questions : 

questions What purifies water in Berlin? Why are extraction wells 40 m deep? How many organisms are there in one cubic millimetre? What did Günther Gunkel discover? Why does the sand purify the water?