Armfield S12-MKII, Инструкция по эксплуатации

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Armfield Instruction Manual
46
For a rise in base level, the observations should include a record of the position of
the nickpoint, and of any secondary nickpoints that appear.
Results
Elapsed time
(min)
Sediment yield
(g/min)
One method of making diagrams of the channel requires two rulers or measuring
sticks, both of which must be rigid and one of which must be at least 1 metre in
length. This long ruler should be laid across the top of the tank from one side to the
other, parallel to the end, and then moved along the tank in steps of 10cm. At each
position, the second ruler is then used to measure the distance from the top line of
the tank to the sand surface, in steps across the entire width of the tank. Reference
points should be recorded for any notable features such as the positions of the
channel sides, sand bars, secondary channels and thalwegs.
Conclusion
Describe the response of the channel to base level change. What factors appear to
contribute to rate of nickpoint migration for a fall in base level? What factors affect the
rate of aggredation for a rise in base level? What real world situations might produce
base level change in a river environment?