Coconut Island Research Day

It was a really sunny and wonderful day working on the Coconut Island with all of you guys. We took water samples at the surface of the water as well as inside the algae to measure the pH. The whole purpose of doing these things is to see how algae in the shallow water column affect the chemistry of the water surround and inside the canopy so that further conclusion of the relationship and the interaction between the algae and the organisms can be drawn.

We first set a very expensive hi-tech device into the water to measure the speed of the water flow near the algae canopy. Since water is dynamic and goes in and out of algae, it is an important factor to determine how water flow will mix the water in and out of the canopy and eventually change the water's chemistry.

We used large plungers with long, thin needles to takle water sample inside the algae. But before that, we had to rinse the plunger as well as the sample bottles with sample water. The bottle's cap, the groove at the mouth of the bottle, and the bottle itself should be rinsed 5 times to avoid any contamination. After that, the needle should be replaced with a small filter with a 0.7-um filter paper inside. The purpose of using such filter is to filter all the large planktons and some waste stuff in the sample water and obtain a relatively "clear" water sample from different location. Later, the water sample will be analyzed in the lab.

The other part of the task that we did on that day was practice how to take small amount of water sample for pH analysis. Since pH is highly dependent on temperature, we should measure the temperature of the water sample as soon as the sample water was taken. In order to do this, the 25 ml plungger with a long, thin needle attached and sample bottle should be first rinsed with sample water. Then, half fill the sample bottle with sample water. Measure the temperature of the sample before it is getting cooler or warmer. Be careful with the fingers that were used to hold the sample bottle! After the temperature was measured, overfill the bottle with sample water. Finally, cap the bottle and make sure there is no air bubbles in the bottle.

It is a pretty interesting workday since I have learned a lot about how to take water samples for different research purposes. What is more, we saw several beautiful sea jellies in the water. They look really similar to algae patches, but they have different color and are very dangerous if people touch them or just get close to them.