Below is a table that would show us how to grade each river

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Introduction

Stage 3: Collection of data When we went out of school to the sites, and we did seven different tasks at each site. Then, when we came back to our school, we did five more analysis. The table below shows which tests we conducted in the field, at each site, and then it shows the tests that we conducted back in the lab at school. In The Field In The Lab 1 noted signs of visible pollution tested for nitrate levels 2 take photographs tested for ammonium levels 3 measure dissolved oxygen tested for any conductivity 4 measure river speed tested for phosphate levels 5 estimate width of river Tested to see whether there was any detergent in the water. ...read more.

Middle

Lots in shallows Several Items Foam Small Odour 3 Brown Abundant Many items Abundant foam Pungent 4 Very Brown Choked Abundant Foam covers river Very smelly Dissolved Oxygen Oxygen inside a river, or any water could be a big problem. It is one of the most important factors in measuring how clean a river is. It can be expressed in percentages, when there is the most amount of water present then there would be 100% oxygen levels. A high oxygen level can be caused from fertilisers running off fields and into the rivers, and it causes an over growth of water plants such as algae, this algae uses up all the oxygen available, and so the other organisms, like fish are not able to get any oxygen. ...read more.

Conclusion

River Speed and Width of River Rivers that have a higher discharge levels would be able to dilute much of the pollution and therefore, they would be able to have a lower visible pollution score, and also better water quality. To measure this discharge, we took measurements of the speed and the river width. We measured the speed of each river by dropping a dog biscuit at a certain point in the river, and we timed how long it took to travel 5m. We did not do a precise measurement for the actual width of the river. Instead we made an educated guess. To obtain both accurate and results, we used three dog biscuits, timing them each, then we took an average of the three. For as accurate as possible results for the width of the river, the same person should make the estimation. ...read more.

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