Diatom Investigation

Question: Are there different diatoms at 10 cm and at 90 cm?
By: Becky, Brianna, Hunter, and Jason

Procedure:Take a sample of the lake core from 10cm. Make a smear slide by putting the dirt on and adding some water. Put the smear slide under a compound microscope and record what diatoms we see in our notebook. Repeat these same steps 2 times. Take a sample of the lake core from 90 cm. Make a smear slide by putting the dirt on and adding a few drops of water. Put the smear slide under a compound microscope and record what diatoms we see in our notebook. Repeat 2 times.

Materials

• toothpick



• compound microscope



• slide



• slipcover



• lake core
  

Data:

At 10 cm:

• 2 Fragilaria Capucina



• 2 Synedra



• 2 pieces of Gyrosigma



• 2 pieces of Asterionella Formosa



• 1 Navicula/Pinnularia
  

At 90 cm:

• 4 pieces of Asterionella Formosa



• 3 Fragilaria Capucina



• 7 synedra



• 2 pieces of Gyrosigma
  

Conclusion:
Claim/Evidence: We found out that there are different kinds of diatoms at 90 cm and at 10cm. At 90 cm there were 4 pieces of Asterionella formosa, there were also 3 Fragilaria Capucina, 7 synedra and 2 pieces of Gyrosigma. At 10 cm we found 2 fragilaria capucina, 2 Synedra, 2 pieces of Gyrosigma, 2 pieces of Asterionella Formosa and 1 Navicula/Pinnularia.

Reasoning: Maybe we incorrectly evaluated which diatoms were what. Maybe one of those areas of time were drier so only certain kinds of diatoms were able to survive. It could have been wetter one year so there were different diatoms.

Further Questions: What different kinds of pollen are there at different depths? When the sediment is larger are there more or less diatoms?