Stream and Cross Sectional Area Essay

Submitted By imogenwebb
Words: 851
Pages: 4

Site number
Description of site
1
The first site we visited was a subterranean spring as well as being the source of the river called lady’s fountain. Additionally it had a ephermal stream and steep valley sides. The bed load was Devonian sandstone and consisted of falling trees. The principal land use of the site was an oak population, which had bilberry plants, and the roots of these stabilize the valley sides. The gradient in the first site was very step due to it being the source where it was on the upper course of the river.
2
The second site contained tributary rivers which met a confluence; additionally it was a –symmetrical valley. The bed load was large and had angular rocks as well as branches in the river. However there was some solution present. The land use and vegetation was extremely similar to site 1 yet was open to more tourists’ with a large range of footpaths. The gradient in this site was not as steep but was still steep as was still in upper course.
3
The third site was a steep v shape valley that was a –symmetrical and had a flat floodplain a wide shallow channel that meandered. The bed load was a small, angular boulders as well as rocks and silt. The land use and vegetation were the same as site 2.the gradient in this site was the steepest of all the samples of sites, this may have been a mistake as it was not accurate.
4
Site number 4 had a flat floodplain and a –symmetrical valley , where the river meandered. The bed load varied in size and was angular in shape. The land use of the sites was the same as site 3, with footpaths and an oak population. The vegetation was primarily the same yet had moss in addition to the oak trees and bilberry plants.the gradient in this site is rather steep however is gradually getting lower as we enter the middle course.
5
moving down to site 5, it was evident that the channel had widened and the velocity had increased , the bed load size varied depending on the section of the channel, at the banks the bed load was small, yet in the middle the bed load was large. Furthermore the land use continued to stay the same the previous sites as well as vegetation. The gradient is even more getting lower as we are making are way to the lower course.
6
The last site had extremely wide channels and low banks. Furthermore site 6 had a leat which is an artificial channel, with more water channelling into the stream the more efficient it becomes. The gradient in this final site was very flat as it was close to the mouth meaning that it is near the lower course.

The variables we were measuring were the flow rate, depth, width and gradient. To calculate the flow rate you have to divide cross sectional area by wetted perimeter. Therefore we had to measure the width, the equipment used was a tape measure, and we choose a site in the river by using systematic sampling to find equal points between groups. In my team we held a tape measure at the either side of the river taut along the natural spirit line and collected results. we took a width reading so we could divide the width by 6 in order to find 5 accurate readings of…