PHYTOPLANKTON, the tiny plant-like organisms that float near the surface of oceans, rivers and lakes, play a vital role in the marine food web and in global oxygen production. Much like terrestrial plants, they photosynthesise, and it is estimated they are responsible for producing between 50 to 80 per cent of the world’s oxygen, making them the planet’s largest source.
However, climate change is taking its toll. Rising sea temperatures are affecting their reproduction and ability to photosynthesise, leading to a decline in their population.
Nutrient pollution from land-based sources and increasing ocean acidity have exacerbated the problem, disrupting the delicate balance of these essential microorganisms.
Professor Dr Mohd Shahrul Mohd Nadzir of the Department of Earth Sciences and Environment at the Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), likened phytoplankton to unsung heroes of the ocean. Yet, he noted with concern that their numbers are dwindling due to global warming.
“Pollution such as plastic waste or chemical contaminants can also pose serious risks. For example, when seawater becomes too warm or overly acidic due to carbon dioxide, phytoplankton struggle to survive,” said Professor Mohd Shahrul in a phone interview with Buletin TV3.
“Studies show their population is decreasing in certain areas, which is alarming because they are vital for oxygen production and the marine food chain,” he added.
Professor Mohd Shahrul stressed that everyone has a role to play in preserving the health of our oceans.
Using reusable bags or bottles to reduce marine pollution, conserving energy by cutting down on electricity use, and limiting driving to curb global warming are just some of the ways individuals can contribute to protecting phytoplankton.
“Supporting clean-up efforts or spreading awareness about the importance of ocean conservation also helps significantly. If we work together to reduce pollution and care for the environment, we can keep our oceans healthy for phytoplankton and all marine life,” he said.
In conjunction with World Oceans Day, observed annually on 8 June, various initiatives by non-governmental organisations (NGOs), local communities and volunteers have been rolled out to promote ocean cleanliness.
These include beach clean-up programmes, environmental education and public awareness campaigns – all of which play a role in protecting phytoplankton and the broader marine ecosystem. - June 23, 2025