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How can industry affect on the amount of oxygen in the river and pH value of water in it?

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We assume that the water from river right beside industry will have less oxygen and bigger pH value than the sample we took from place far from industry.

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We took three water samples from three different places: before, right beside and after industry. We tested the amount of oxygen and pH value in every sample. After we got the results we compared them between our cities: Nysa, Rotterdam and Buzet.

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• pH papers
• O2 indicators
• pH meter

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Our study area has a temperate climate. Each of the samples was taken from a place closer to the industry, our examine was made during winter. Rivers from which we took water were surrounded by vegetation, at the bottom of the rivers there were plant lives, silt and stones.

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Our study area has a warm and temporate climate.Each of the samples was taken from a place close to the industry,also our examine was taken during the winter.River from which we took our results was surrounded by plants,rocks.

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Indicator strips were inserted into the water samples and coloured. On the basis of a comparison of the colour with the scale, we obtained the result.

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We put two electrodes connected with pH meter in glass with samples and then pH meter showed us value.

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For oxygen testing we used a set of three reagents. First, we added 6 drops of the first reagent marked ''1'' to the water samples, then 6 drops of the second one. Finally, we added 6 drops of the third reagent and waited 10 minutes for the result, which we compared with the scale.

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We collected 2 samples per week. Dates we took water were 17.01. , 19.01. , 23.01. , 26.01. and about 5 PM. The difference between results of samples were little. Value of pH was going about 7 to 8 and the oxygen amount was between 8 and 10.

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Value of pH before industry was 7.47, right beside the industry 7.57 and 7.66 after the industry.We didn't measure amount of oxygen because we weren't able to do it.

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The result of sample right beside industry was 8,67 mg/l oxygen and pH value was 7.40.
Result of sample farther from industry was 9 mg/l oxygen and pH value was 7.30.
The sapmle farthest from industry was 9.33 mg/l oxygen and pH value was 7.10

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We assumed that the sample right beside industry is going to have a bigger pH value than far from industry but our assumption was not correct. Sample after the industry had a little bigger pH value and also a smaller amount of oxygen. We think that its because the water from the factory mixed with the river water.

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Interpretation of results (oxygen amount)

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Interpretation of results (oxygen amount)

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Like we assumed, the biggest amount of oxygen in water was in place farthest from industry and the smallest one was in place right beside industry.
We think that this was influenced by the large amount of plant life located next to the river farthest from industry and by the lack of pollutions casued by the "life of the city".

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We used GLOBE hydrological testing protocols.

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Similar examine to this one could be held in future. Samples can be taken every three months, each at different season. It would help to control the state of water.