Plankton Bloom Turns Sea Off Thailand’s Ko Lan Green

The sea off Thailand’s Ko Lan island has turned a striking shade of green following a plankton bloom, prompting many tourists to stay out of the water and raising concerns about falling oxygen levels beneath the surface.

The discolouration has been linked to a rapid increase in plankton, microscopic organisms that can multiply quickly when environmental conditions are favourable.

While the green water has drawn attention from visitors, scientists are more concerned about the potential impact on marine life. Large plankton blooms can reduce oxygen levels in the water, particularly when the organisms die and decompose.

Lower oxygen concentrations can place stress on fish and other marine species and, in severe cases, contribute to fish deaths or wider disruption of the local marine ecosystem.

Ko Lan, located off Thailand’s eastern coast near Pattaya, is a popular destination known for its beaches and clear coastal waters. The sudden change in water colour has discouraged some tourists from swimming while authorities and researchers monitor conditions.

Scientists are assessing the extent of the bloom and its effect on oxygen levels to determine whether the phenomenon poses a broader environmental risk.

Plankton blooms can occur naturally, although factors including warm water, sunlight and increased nutrient levels can encourage their development. Excess nutrients entering coastal waters from runoff or other sources can sometimes intensify such blooms.

The immediate concern is not simply the unusual appearance of the sea but whether declining oxygen beneath the surface could affect marine organisms if the bloom persists.

Authorities are expected to continue monitoring water quality around Ko Lan as scientists track changes in plankton concentrations and dissolved oxygen levels.

Source: Reuters