More work has been done in the past week, the seawater was heated and acidified for our experiments
We also staining our shells so that we can have a better time control for which part of the shell mass is growing under the assigned pH in this experiment. Those shells were separated into different flower pots.
In order to evaluate how the animal adjust the pH inside the shell, we also aim to measure the pH from the extrapallial fluid (EPF), in which the chemical compositions were considered directly related to the formation of the carbonate shell. To measure the pH in the shell, we need to drill a small hole on some of the shell. A segment of pipet tip will be glue on it so that we can keep the entrance for future pH measuring.
To ensure the EPF won’t exchange with the seawater outside the shell, we have to seal the opening. And then put them back to their home!
When you see the shells open their valves like the pictures below or they dig into the sands, they are telling you, “We are happy living here!!!”
After two weeks of efforts, our pH control flow through system is running, and we take the first measurement last Saturday.
Wish us the best of luck for the next eight months. We feel excited to learn how the boron isotopic compositions in the shells relate to the ambient seawater pH, as well as the pH in the shells, do you?
Our pH control culture experiment is building up in the Troms Marin Yngel (TMY) now! Most of the mechanical constructions will be done so in a couple of days soon. pH meters were calibrated and CO2 and water system will operated next Monday. Hopefully the A. islandica can live happily under out different pH treatments later in the growth season.
People worked hard together to make the experiment design come true.
The progress we made from the past week: The set-up of master tank (top), mixing tanks (coolers in the third picture) and experimental trays.
New home we made for individual clam.
Samples were labeled, measured and weighted
To have time control, we also stained the shells.
In this experiment, we also seek to have in-situ pH measurement from the extrapallial fluid (EPF). To avoid hurting the animals, practices with shells are necessary. (Also, we have to learn not to hurt ourself at the same time…I totally did not intend to drill a hole on my finger…). A pipet tip is mounted on the surface of the hole and will be sealed with parafilm. Later on the measurements will apply from the hole we drill.
Next week we will start regulate the pH levels and leave the clams into different treatments to acclimate the new environment. Then, the experiment will be ready to start!
In addition to the glacier studies, one branch of GIGL uses a cold species of clam, Arctica islandica (A. islandica), as an archive to learn more about our climate system. We aim to confirm the relationship between boron isotopic compositions of the bivalve mollusk A. islandica and the ambient seawater pH. We hope to reconstruct the recent history of ocean acidification and understand how ocean chemistry reacts with respect to the increasing level of atmospheric CO2.
This year, we have an international collaboration culture experiment in Tromsø, Norway. Thanks to our collaborators from Norway and Iowa State University, we just got a bunch of living shells from the coastal region of Ingøy, Norway (71°05′03″N 24°03′29″E). We are going to rear them in four different pH levels from 7.5 to 8.1 to see the impacts of ocean acidification on the chemical compositions in the shells and the growth of the animals.
The culture experiment will be set up in the upcoming few days. More exciting updates will coming soon!!!
Michael (Senior Researcher from Akvaplan-niva in Tromsø, Norway), Thorleif (fish man on Ingøy island), and Maddie (Graduate student form Iowa State University) successfully collected samples last Wednesday.
Living A. islandica that will be used later in this boron-pH (CO2 and ocean acidification) project.