The sulfur explosion that occurred in Lake Batur, Kintamani a few days ago caused fish farmers in the local lake to suffer losses. Much fish that was cultivated in floating net cages died.
The Department of Agriculture, Food Security and Fisheries of Bangli Regency noted that the dead fish reached around 14 tons in total. Many fish farmers had losses in the area of Buahan and Banjar Dukuh villages, Abang Batudinding Village.
In Buahan Village, the number of fish deaths due to sulfur eruptions was recorded at 11.950 kilograms. Meanwhile, in Banjar Dukuh, 2.400 kilograms of dead fish were recorded. If calculated, the total losses suffered by fish cultivators in the two villages reached around IDR 350 million.
The cause of the death of the fish in Lake Batur is due to the upwelling phenomenon.
As is known, since Sunday (28/2/2021), the color of the water in Lake Batur has changed due to rain and strong winds around Lake Batur for three consecutive days.
The weather conditions trigger the rise of sulfur from the bottom of the lake, known as upwelling. This condition causes all pollutants to be mixed and endangers the life of the biota in the lake.
This includes the content of sulfate and phosphorus which binds oxygen in lake water. This condition causes the oxygen content in the lake water in the area around the sulfur eruption to drop dramatically.
“There is a phenomenon of upwelling, stirring between surface water and lower lake water. The underwater water rises and causes sulfur which causes fish to die,” explained Head of PKP Bangli Regency I Wayan Sarma.
This phenomenon occurs every year between January and February. However, last year 2020 it did not happen.
Sarma explained, this January his party had warned residents regarding the potential for the upwelling to emerge. However, it is suspected that these residents chose to speculate.
“Farmers and fish farmers there, they are familiar with such conditions. Only before (it happens) we keep reminding that January to February is an estimate of this phenomenon. Therefore it regulates the spread,” he said.
“I have given a circular last January. If it is necessary to harvest early, so harvest earlier to reduce losses,” he said.
Sarma said that currently, the water conditions of Lake Batur are already normal.
“It’s starting to normalize, because the rain has started to decrease and the gusts of gusts have been reduced,” said Sarma.
Just the greenish watercolor is still visible at several points such as Songan, Kediasan, Buahan, and Terunyan. I Wayan Sarma hopes this annual phenomenon will not spread.
After the mass fish deaths, Sarma said that fish cultivators need to clean the nets from fish carcasses and lake waters. He advised not to sow new fish seeds for some time.
His party has also invited a police unit Satpol Air Polres Bangli to work together with the community to clean the lake waters.
photo by KOMPAS.com/IMAM ROSIDIN