The aim of this field work was to study the long profile and its characteristics of the River Lym. The velocity then drops at the mouth where it tends to deposit its load The velocity then drops at the mouth where it tends to deposit its load This is the general long profile of the river where the gradient decreases as you go down the river. The source is highest point of the river basin which usually is a mountain. This is the general long profile of the river where the gradient decreases as you go down the river. The source is highest point of the river basin which usually is a mountain. The hypothesis of this field trip was to compare the long profile of a model river to the long profile of the River Lym and its characteristics. I came up with this hypothesis by researching into the geographical theory of the long profile of a model river and then wanted to compare it to a standard river in order to see which anomalies are present that is affected by nature or human activity. Velocity then increases as you go down stream because the cross sectional area increases relative to the wetted perimeter which reduces friction despite the changes in gradient. Velocity then increases as you go down stream because the cross sectional area increases relative to the wetted perimeter which reduces friction despite the changes in gradient.
I carried out my field work along the River Lym in Lyme Regis which is on the South West Coast of England shown in the map. Hazard| Danger | Likely hood | Risk| Precaution| Response| Vegetation HazardSpikes/stinging nettles| 1| 3| 3| Be vigilant| Wash yourself| Slipping on rocks| 3| 1| 3| Don’t climb on them| First aid| Tripping and slipping| 3| 2| 6| Enter at a safe point and don’t jump in| Get out and rest| Hypothermia | 3| 1| 3| Check weatherAppropriate clothing| Hospital | Drowning | 3| 1| 3| Sensible in the riverNo less than threeLook out for each other| Funeral| Ranging pole injuries| 2| 1| 2| Be careful| First aid| Traffic danger| 3| 1| 3| Single file facing oncoming trafficDesignating cross points| Ambulance|
I choose these study sites using stratified sampling. I had decided that I wanted to study five points of the River Lym. The main factors that determined these sites were accessibility and safety. I decided that all sites must have roughly an equal spread. The first site was chosen at the highest accessible point of the river. And our last point was chosen in the urban area, as close as you could get to the mouth considering safety issues. Then each point was chosen at roughly one kilometre apart to make it systematic but then repositioned due to accessibility factors. For example our second study site was on privet land so we relayed on the permission of using this land to study the river. Our third site was on a public park which leads on from and to inaccessible areas so we carried out the field work in the park. The forth site was part of a forest which then passed by a horse field where we studied. Therefore I believe that all these sites are good representatives of the course of the River Lym.
At each study site we collected a number of primary data across and along the channel. Our aim was to work out the cross section, wetted perimeter, velocity, bed load size and roundness as well as the gradient in order to compare these results with our geographical knowledge that we had gained by studying a model river from the textbook.
The cross sectional area was predicted to increase and was worked out by multiplying the depth and width together. We measured the width using a tape measure by taking measures from the bank at the current flow on both sides. We then divided the width by 10 and took 11 readings of the depth across the channel using a meter ruler. I then calculated the mean or average depth which I multiplied by the width to get the cross...