Project News

Tuvalu's ocean seems very beautiful with amazing blue color.

However, unexpected contamination was found by our research.

We coincidentally found the sulfide belt at the seashore on the transect survey.

Hydrogen sulfide is extremely hazardous to life. Even a small quantity, it is harmful to creature's growth. Residents are apprehensive about these bad influences, especially those who utilize the coast for daily activities such as bathing and fishing.

Once the seabed sulfurate, recovery is not easy and the situation becomes increasingly worse, unless measures are taken.

Responding to our report, the Prime Minister requested that we identify the cause of sulfide as soon as possible. This research was carried out in February.

Measuring the amount of organic matters

How does sulfide occur?

Bacteria uses oxygen when it decomposes the organic matter, the same way we human beings do. However, if oxygen is scarce, like at the seafloor, some bacteria will use sulfate: SO42 to decompose the organic matter and then sulfide is generated.

Therefore, sulfide is produced under scarce oxygen conditions where there are high levels of organic matter and sulfate: SO42.

We sampled ground and coastal water at 19 sites. Water samples are being analyzed to clarify the quantity of organic matter and types of chemical materials. This information is referred to the sulfide distribution at the seashore to identify the cause.

Water sampling from the septic tank

Because this activity was broadcasted on the radio keep ahead of time, residents noticed the research activity. They were very cooperative when we asked to obtain water samples from their septic tanks. Someone expressed his thanks to the field survey in heavy rain. Another asked us when the results would be reported.

Residents feel the contamination of the seawater vaguely, however their suspicions have never been proven with numerical value and cause. They are looking forward to the result.

We will report this result at the Program Coordination Committee meeting on March.

Warding responsible: Fumiko Matsudate (Project Coordinator)