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Geography Investigation (Data collecting skills (measuring beach profile…

- - - - Data is unreliable
      - Mistakes when collecting data
- - - - Ranging pole
      - Clinometer
      - Measuring tape
    - - Identify a transect on the beach. Select points on the transect where the beach gradient changes or at intervals of 2 metres.
      - 2.Place ranging pole at the first and second points. The first point should be ideally at the low tide level.
      - Use a clinometer to take a bearing of the angle of the slope.
        :star: The bearing should be taken from the point on the ranging pole that coincides with the same point on another ranging pole.
      - Use a measuring tape to measure the distance on the ground between the two point.
      - Repeat this process at all points along the beach and record all the angles and distances on a recording sheet.
    - - Ranging poles are slanted, causing measurement of angles to be inaccurate
      - Ranging poles are stuck into the sand at different depth, causing the measurement of angles to be inaccurate.
      - Edge of the coast/low tide level is difficult to determine.
      - Change in beach profile is unobvious to naked eyes, causing inaccuracy when selecting points.
      - Reading the clinometer inaccurately due to parallax errors.
  - - - Meter ruler
      - Stopwatch
    - - Push a meter ruler into the nearshore or foreshore area. Record the height of ten consecutive wave crests and troughs that pass the ruler.
      - Concurrently, use a stopwatch to record the time taken for ten wave crests to pass the meter ruler.
      - calculate the wave height of each wave by substracting the height of wave troughs with the height of wave crests.
      - 4.Calculate the wave period, which is the time taken for each wave to pass the meter ruler by using the formula T= total time\10
      - Calculate the wave length using formula 1.56 × T²
      - Calculate wave steepness using formula wave height\wave length
    - - Meter ruler is slanted causing inaccurate measurement of wave crests and trough.
      - Incoming waves are too fast for reading to be recorded, causing inaccurate measurement of wave crests and trough.
      - Parallax error when reading off the metre ruler.
      - Some waves are too small to be measured, causing inaccurate measurement of time taken.
      - Human factors such as ships passing by and people swimming.
  - - - Wind vane
      - ranging pole
      - buoyant object
      - measuring tape
      - :question:stopwatch
    - - Identify the stretch of coast where the longshore drift will be measured
      - Use a wind vane to determine the direction of wind and record on a recording sheet.( to prove the hypothesis that the direction of longshore drift is influenced by the direction of wind)
      - Near the water's edge, stick the first ranging pole to indicate the starting point and through a buoyant object a meter away from the water's edge. :question:(start the stopwatch)
      - Observe the travelling path of the object for 10 mins. Stick another ranging pole into the sand to indicate the end point where the finally lands.
      - Use a measuring tape to measure the distance between two ranging poles and record on a recording sheet. The direction is determined by noting the position of the second pole in relation to the first pole.
      - Evaluation
        
        Waves may be disrupted by human interference such as boats passing by, making the reading of inaccurate.
        
        Difficult to gauge the distance when throwing the object. It may be more than 1 meter :question: (does it matter?)
        
        Ranging pole on the starting point and the end point may not be on the same line parallel to the coastline, causing inaccurate measurement of distance.
  - - - Spade
      - Sieves
      - weighing machine :question:
    - - Identify a line of transect where sediments will be collected
      - Using systematic sampling, determine sampling points that are two meters away from each others along the transect. Use a spade to collect 100 grams of sediments at sampling point.
      - Collected sediments are brought back to laboratory for analysis. A set of sieves are used to sort sediments according to their sizes. (If sediments are wet, use an oven to dry the samples before sieving it)
      - Place 100 grams of sample onto the top sieve and cover it. Proceed to gently shake the set of sieves with a circular motion for 5 mins.
      - Weigh the sand that is retained on each sieve and find out the proportion of the weight of each sediment size to the total weight of sediments.
      - Place the sieve with the largest mesh hole on the top and the one with the smallest mesh hole at the bottom.
    - - Human interference (littering, building of sandcastles, beach nourishment) may have disturbed the sediments in an area, making data collected unrepresentative of the entire coast
      - Some sediments may still be trapped on the sieves, causing inaccurate measurement of weight of certain sediment size.
  - - - Use a 1m by 1m quadrat to identify samples on the areas of study. Place the quadrat on the beach at intervals of fixed distance to endure systematic sampling.
      - Generate random numbers that correspond to the boxes within the quadrat using a random number table. 10 to 15 samples are randomly collected from the boxes indicated by the random numbers.
        :red_flag: OR
        Use systematic sampling, collect samples from one box every 10 boxes.(e.g. from number 1, 11, 21, etc)
      - Use a Vernier caliper to measure the long axes of each sediment and record it in a recording sheet.
      - Use the Power's scale of roundness to identify the shapes of the sediments, whether it is rounded or angular,
    - - Difficult to make sure the samples are collected randomly as there may be biasness in play (only pick up sediments that are not so dirty)
      - Parallax error when reading of the Vernier caliper, causing in accurate measurement of sediment size.
      - Power's scale of roundness may not be useful as the sediments may not be perfectly categorised into the 6 specific classes.
    - - Quatrat
      - Vernier caliper