CO2 absorption and O2 release by Posidonia oceanica
Investigation of the experiment on CO2 absorption and O2 release by Posidonia oceanica
1. The questioning: "Does Posidonia oceanica absorb CO2 and release O2?"
2. The hypothesis: As indicated in numerous scientific reports, Posidonia oceanica has a major role in the regulation of the oxygen and carbon dioxide cycle in the marine ecosystem. It should therefore absorb the C02 that we will inject into it.
3. Materials:
- 1 CO2 sensor
- 1 arduino uno board
- 1 grove shield (optional)
- IDE arduino application on computer
- 1 transparent tray
- 1 bent tube
- Scotch tape
- 1 match
- 1 screwdriver Posidonia leaves - 1 plastic bag
4. Experiment:
- Create a program via the arduino IDE application on the computer.
- Place the posidonia leaves in the tray and cover them with the plastic bag and close the bag tightly with the rubber band.
- Make a hole in the bag with the screwdriver to pass the CO2 sensor connected to the arduino uno board (on which there is the grove shield) itself connected to the computer.
- Make a second hole to pass the bent tube.
- Surround the two holes with tape so that the whole thing remains airtight.
- Start blowing CO2 into the elbow tube while exhaling, then plug it with a finger.
- The data captured by the sensor are displayed on the monitor of the arduino IDE - Wait a few minutes.
- Approach the match (lit) to the elbow tube and remove the finger.
5. Results :
We entered our results in an Excel table to represent them in the form of a graph :
When the finger is removed and a flame is presented in front of the bent tube the flame becomes more intense
6. Interpretation of the results:
We can notice that after insufflation, the Co2 rate increases rapidly before stabilizing and starting to decrease. Our structure being watertight, we can affirm with certainty that it is the posidonia leaves that have absorbed the Co2.
Moreover, when we approached the match to the bent tube, the flame increased, which confirms the important presence of O2 and thus proves the role of Posidonia oceanica in the regulation of the oxygen cycle in the marine ecosystem.