A-level Experiments

In recent weeks, the A-level students have been conducting their own experiments using the reefs and ecosystems on our doorstep to further their understanding of the course material.

Ocean Acidification

To demonstrate and understand the possible effect of ocean acidification on corals and their calcium carbonate skeletons, the students designed a lab experiment to see exactly how acid affects coral.
Tom's acidic solutions and test coral fragments

The students prepared solutions with different levels of acidity and exposed pieces of dead coral fragment to each solution to simulate the effect that an increasing level of ocean acidity would have on live corals.

The students found that the more acidic the solution, the more mass the dead coral fragments lost. This was due to the calcium carbonate structure of the dead corals being dissolved into salt, water and carbon dioxide by the acid present in the solutions
Christine measuring mass loss

The results of the experiment were sobering and illustrated the potential devastating effect that ocean acidification may have on coral reef ecosystems around the world.

Plant Physiology: Photosynthetic rate

Sophia collecting produced 
oxygen for measuring
To demonstrate and understand the different factors which affect primary producers and their rate of photosynthesis, the students designed a natural experiment to see how light intensity affects the rate of photosynthesis of sea grass.

Graeme checking his experimental
set up
The students used oxygen production of the sea grass (Thalassia sp.) in our lagoon for a proxy of photosynthetic rate. By comparing the light intensity throughout the day and measuring oxygen production at specific intervals, the students found that light intensity has a great impact on photosynthetic rate. The students found that more oxygen was being produced when the sun was stronger, confirming their hypothesis.
Home-made oxygen capture kit