Methods

• method 1 - width

  • tape measure - must be tight
  • measure width of river - bank to bank
  • at 2 sights on the river
• method 1 - width - positives

  • data to test the hypothesis
  • easy to carry out
  • no specialist equipment required
• method 1 - width - negatives

  • human error
  • tape measure may not be tight - not accurate
  • only visited 2 sites
  • only did 1 measurement at each site
• method 2 - depth

  • 5 even measurements across river
  • find the mean
  • metre ruler stick - measure from water level
  • systematic sampling
• method 2 - depth - positive

  • provides data to test hypothesis
  • easy to carry out
  • no specialised equipment
• method 2 - depth - negative

  • rocks on river bed - create anomalous results
  • human error in reading metre ruler
  • only went in one season
  • only visited 2 sites