1. Before you start
Formulating enquiry questions
Rivers are dynamic systems, they are constantly changing – modifying their own channels and the wider landscape. Changes take place both spatially and temporally – spatial changes may occur laterally or longitudinally in the river channel, across the cross profile or along the long profile.
- How and why does velocity change across the cross profile of River X?
- How and why does bedload size and roundness change across the cross profile of River X?
- How and why does discharge change along the long profile of River X?
- How and why does the cross profile of River X change along its long profile?
Questions that look at temporal change can be very interesting, but are often less practical for the GSCE geographer, involving repeated visits to a site for data collection, for larger rivers secondary data from the National River Flow Archive or Environment Agency gauging stations can add a temporal aspect to your investigation.
Rivers investigations can focus on changes in any of the channel characteristics, to ensure some stretch and challenge for more able students it is wise to choose some of the more complex characteristics – for example an investigation that looks at changes in cross profile may be more challenging and interesting than an investigation into width or depth alone.
Questions focussing on changes along the long profile, or downstream changes lend themselves well to a hypotheses testing approach, students formulating a number of hypotheses which they will test en route to answering their question.