Apr 7, 2013

Research voyage to Mageshima Island(馬毛島沖で調査航海を実施)

We got aboard the TS Nansei Maru this week to conduct the research voyage in Osumi Strait, northern end of the Ryukyu Archipelago. We had measured vertical gradient of the underwater light intensity, temperature and salinity using CTD at some sites off Mageshima Island and Kagoshima Bay. We had also collected the sand sample of sea floor using the bottom sampler. On the way back to Kagoshima Bay, we also observed the presence of drifting seaweed (Sargassum horneri).


On the sampling site, we used the CTD that can be measured automatically  light, temperature, salinity, pH and dissolved oxygen. Especially, underwater light data is essential for our study. After this voyage, students will be calculating the consumption coefficient of PAR.

Two students (left) are just now operating the CTD. Mr Fukuda of the first mate of Nanseimaru (right) is kindly supporting its operation. Actually, it is "research" for us, but is carried out as the practical class of training voyage (credit 1) for students. After the measurement, we collected sand on the seafloor using the bottom sampler.

This is the photo of Mageshima Island that is located on the offshore of western part of Tanegashima island. It was taken at the sampling site. Depth of the site was around 35m, seafloor is thought to be mostly flat from here through the shore.

After the survey, due to the occurrence of spring storm, we canceled a stop at the port of Nishinoomote, Tanegashima Island, and came back to Kagoshima Bay. Next day, measurements were conducted at some sites of Kagoshima Bay.

Deckhand is just checking the status of bottom sampler.

Sample was collected.