Investigating abundance and Distribution

• What`s an abundance?

  It refers to how many organisms there are
• What`s a distribution?

  It refers to where the organisms are
• How do ecologists use method of sampling?

   they only measure a subset of the organisms, and use that subset to make predictions about the whole population
• What is a quadrat for?

  To measure abundance
• What is a transect for?

  To measure how distribution changes
• What is a quadrat?

  A quadrat is a square or rectangular frame that has been subdivided into lots of smaller squares, used in ecological studies to sample and measure plants or animals in a specific area.
• What`s the method of sampling using quadrat?

  • Place multiple tape measures along the length and width of the field, forming a large grid.
  • Use a random number generator to generate 10 pairs of random coordinates.
  • Place quadrats at those coordinates and count how many dandelions are found in each quadrat.
  • Calculate the mean number of dandelions per m2.
  • Estimate the total population size using our mean number of dandelions per m2 and the total area of the field.
• What are the transects used for?

   to observe and record changes in species distribution across an area
• What`s the method to use a transect line?

  • A transect line (usually a tape measure) is laid out in a straight line between the lake and woodland.
  • Quadrats are placed at regular intervals along the transect line. 
  • The abundance of dandelions is measured by counting the number of dandelions in each quadrat along the transect line, from the lake to the woodland.
  • Steps 1-3 are repeated using new transect lines (these must be parallel to the first). By using multiple transect lines, the data gathered is more representative of the area