Adianto P. Simamora Jakarta Post 15 May 10;
The high rate of pollution in the sea has sparked algal blooms, which can pose a serious threat to the country's fishery sector amid the government's plan to boost fishery production, a seminar heard Friday.
The Indonesian Maritime Council warned algal blooms, also known as the red tide, could grow to an uncontrollable rate if there was no improvement in watershed management to minimize the influx of pollutants into the sea.
"The red tide may hamper the government's target to produce up to 350 million tons of fishery products per year since about 70 percent of the target would be from marine culture," the council's secretary, Rizal Max Rompas told a seminar Friday.
The pollutants from land agriculture, industries and domestic waste into the sea through the rivers can increase nutrients that will feed the rapid proliferation of the harmful algae, he said.
The red tide could reduce oxygen and increase toxins that would threaten the massive death of marine biota such as fish.
Pollutants will also worsen the quality of sea water that can disturb the population of marine organisms.
Red tides can be seen with the rapid change of sea water colors including red, green and brown.
Rizal said that a number of red tide cases were found in Indonesian waters since the 1980s, causing the death of many fish.
He said that Jakarta Bay suffered red tides at least five times in 1992, 1994, 1997, 2005 and 2006, marked prominently by a sea of floating dead fish.
"The red tides also hit Ambon Bay in 1997 and the Cirebon-Indramayu waters in 2007. It also hit the eastern part of Bali coastal areas four times and East Nusa Tenggara water three times," he said.
The incidents both in Ambon and East Nusa Tenggara reportedly caused the death of 15 people after they consumed fish contaminated with the toxin. "Red tides will cause economic loss. It will cause the harvest failure of shrimp and fish, and impact on the country's tourism sector," he said.
Indonesia has about 7.9 million square kilometers of sea, with a coastline of around 108,000 kilometers.
Director general of spatial planning at the Public Works Ministry Imam Ernawi said that integrated management of watershed from upstream to downstream areas could reduce the phenomena of red tides in Indonesia.
He said the use of chemical fertilizers for agriculture could also lead to the blooming of algae in the sea and coastal areas.
"To anticipate red tides, the government should manage the allocation of protected forest in upstream and coastal areas to maintain the quality and quantity of water," he told the seminar.
A senior official from the agency for assessment and application of technology (BPPT), Jana Anggadiredja, said that an early warning system using buoy technology and remote sensing could be used to mitigate the algal blooming.
A marine expert from the University of Japan, Yasowo Fukuyo, said satellite technology could be powerful in detecting the movement of red algae, including in Indonesian seas. He said that it could detect red tides in the area of less than 10 kilometers to 1,000 square kilometers.
He predicted that the red tide cases could be far larger in Indonesia than Japan due to its huge water area.
"We record some 200 red tides a year in Japan, I suspect red tide cases are much bigger in Indonesia," he said.
Jana said most red tide occurrences were harmful.
