# Debden Brook Rivers Cousework Analysis and Conclusion

Analysis and Conclusions

In this section I intend to analysis my results and state whether my hypothesis were verified (proved correct) or nullified (proved incorrect) I will provide reasons as to why by showing a detailed analysis of actual figures from my graphs.

In the second part of this section I will evaluate the results by looking at factors that could have affected the accuracy of my results and conclusions i.e. limitations. I shall look at ways in which my methods might have been improved.

I must also look at the Bradshaw model and see if the characteristics of this specific river follow the general trend of his model.

Hypothesis 1 – The Width of the River Increases with Distance Downstream

This hypothesis was proved correct because figure one shows that the width of the river steadily increases with distance downstream. The water width of the river increased from 0.83m at site 1 (Debden Brook) to 1.95m at site 2 (Debden Brook) and 8.53m at site 3 (The River Roding). This is because streams generally carry more water in their channel as distance from the source increases because water is added to them from tributaries, however there are some exceptions (e.g. The River Mersey due to human activity).  This will also increase lateral erosion as the water will be moving faster and carrying more load.  As a result, the width increases. This hypothesis corresponds with the Bradshaw Model because fig.1 shows the width of the river increasing with distance downstream.

Hypothesis 2 – The Depth of the River Increases with Distance Downstream

This hypothesis was proved correct because figure two shows that the average depth of the river significantly increases with distance downstream. The average water depth of the river increased from 0.08m at site 1 (Debden Brook) to 0.21m at site 2 (Debden Brook) and 0.55m at site 3 (The River Roding). This increase is because of greater downwards (vertical) erosion due to increased water velocity, discharge and load resulting in more abrasion due to traction and saltation. This hypothesis corresponds with the Bradshaw model because fig.2 shows the depth of the river increasing with distance downstream.

Hypothesis 3 – The Gradient of the River Decreases with Distance Downstream

This hypothesis was proved correct because figure six shows that the depth of the river steadily decreases with distance downstream. The gradient of the river increased from -5º at site 1 (Debden Brook) to -4º at site 2 (Debden Brook) and -2º at site 3 (The River Roding). This is because rivers have their source in the watershed before descending to sea-level at the mouth.  The long profile of a drainage basin clearly shows a decrease in gradient. This hypothesis corresponds with the Bradshaw model because fig.6 ...

#### Here's what a teacher thought of this essay

Excellent integration of data, theory and terminology throughout the analysis. More explicit and detailed linkages BETWEEN the different factors and measurements are needed for a higher rating- eg. how does velocity link to discharge and rate of erosion? Which then links to x-sectional area. Very good variety of limitations, with some extended explanation of how these issues may affect the results. To gain extra marks here - go a stage further to consider that these possible errors and therefore inaccurate results may therefore lead to incorrect conclusions for each hypothesis.