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Comparison of results

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Comparison of results
Cheap analyses
Kraichbach (D)
Brentella (I)
Sete Cidades (Pt)
Szilas (Hu)
Rio Pontones (E)                      

Compare the the most important results (spring time) of chemical analyses of our 5 water eco systems. All the measurements were done by TAPAS students and their teachers. If you put your computer mouse on the charts you can read background information about the meaning of the values.

The chemical results of all 5 eco systems in detail:

Italy Spain Germany Hungary Azores
The pH-Value shows us how acid or basic the water is. Drinking water or water of clean eco systems has a pH-Value between 6,5 and 7,5 (almost neutral). All animals and plants living in a water eco system are well adapted for the pH-conditions in their surrounding. If the pH-Value changes, the water animals will become ill, can‘t breed or will die. Acid or basic substances come into water eco systems through household and industrial pollution or through acid rain.

Phosphates (PO43-) are an important part of fertilisers, washing powder, food, excrements …). They are responsible for the eutrophication of water eco systems. The plant overgrowth there (caused by too much phosphates brought by rain and sewages) results in putrefaction and later in too less solved Oxygen. Life in the water system is going to be killed. The EU standard value for water is 0,56 mg/l. Temporary a maximum of 6,95 mg/l is allowed.
The Solved-Oxygen-Value (O2) depends on the water temperature. If you have a higher temperature you will measure a lower Oxygen-Value. The value is also low if the water contents lots of dead organic material (e.g. dead animals, dead plants an algae, excrements…). The water quality falls. Healthy water eco systems have an Oxygen-value of 8-10 mg/l.

Nitrate (NO3) isn’t directly poisonous. You can find it all over the nature and in lots of bio-chemical cycles. Plants need it for growing. The problem is that Nitrate can be changed into the dangerous Nitrite. Nitrate reaches water eco systems through rain water, that flushes it from fertilised fields away. It also reaches the water eco systems through purification plants and exhaust emissions (cars and lorries). In water eco systems with too much Nitrate there will be often a proliferation of algae.

Nitrite (NO2-) is very poisonous. Only 2 g can be very dangerous for a man. It cuts off the supply with Oxygen in the blood of animals or humans. Fish will die if the water contents too much of it. Enzymes in bacteria and fungi are responsible for the change from Nitrate to Nitrite (Nitrate reduction). Also Nitrite is the starting substance for carcinogenic substances (Nitrosamine). More than 0,2 mg/l Nitrite in Water means: The water is very contaminated. Water eco systems of a very good quality have a value of less than 0,01 mg/l. Nitrite is part of lots of salted food. That’s why you shouldn’t eat too much salted sausage.
The Ammonium-Value (NH4+) is like the Phosphate and Nitrate-Value a very important indicator for the water quality. Plants need Ammonium for growing, but too much of it results in putrefaction. Ammonium can also be changed into the dangerous Nitrite. The EU standard value for drinking water is 0,05 mg/l. Temporary a maximum of 0,5 mg/l is allowed.

 

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