World Seagrass Day: The overlooked marine treasure

Every year on March 1, World Seagrass Day is celebrated to raise global awareness about seagrass conservation. Declared by the United Nations in May 2022, this observance emphasizes seagrass' vital ecosystem services, including its role as a blue carbon resource. With the intensifying global climate crisis, protecting seagrass has become increasingly important.

Seagrasses are key components of marine ecosystems. They form the base of the marine food chain and serve as essential carbon sinks and water purifiers. Seagrass meadows can absorb substantial amounts of carbon dioxide, helping to mitigate climate change.

Studies show that seagrass meadows store more carbon per unit area than other ecosystems, and their carbon stays locked away longer. In some areas of China's coastline, seagrass meadows sequester about 543.5 grams of carbon per square meter every year.

Thus, conserving and restoring seagrass meadows is crucial for both ecological balance and combating climate change.

In China, seagrass is primarily found in the South China Sea, the Bohai Sea and the Yellow Sea. The South China Sea is home to 15 species of seagrasses, with Halophila ovalis being the dominant species. In contrast, the northern regions have nine species, with Zostera marina being the main species.

The largest seagrass meadows are found in south China's provincial-level regions of Hainan, Guangdong and Guangxi. In total, China's seagrass meadows cover nearly 8,800 hectares, with Hainan alone accounting for 64 percent.

However, human activities, climate change and water pollution have caused significant degradation of China's seagrass meadows. Over 80 percent of seagrass beds in China's coastal areas have disappeared between 2015 and 2020. This alarming decline underscores the urgent need for protective and restorative measures.

To combat this, China has implemented several protective actions. The government has conducted thorough surveys of seagrass resources, especially in the South China Sea.

Understanding the species, distribution and environmental factors in Hainan, Guangdong and Guangxi, helps strengthen conservation efforts, according to Xiao Xi, a professor at the Ocean College, Zhejiang University.

Additionally, multiple seagrass protection zones and scientific monitoring stations have been established, such as the Hepu National Dugong Nature Reserve in the Guangxi Zhuang Autonomous Region and the Leizhou Seagrass Protection Zone in Guangdong Province.

China is also engaging in international collaborations to share seagrass protection technologies. In cooperation with countries like Saudi Arabia, Spain and Australia, Zhejiang University is advancing seagrass restoration techniques. As many experts emphasize, international collaboration is key to global seagrass conservation.

In recent years, China's Two Sessions have increasingly focused on ecological civilization, and policy support for seagrass conservation is growing.

The 2024 "White Paper on China's Marine Ecological Environment Protection" emphasizes the promotion of carbon sequestration and enhancement in blue carbon ecosystems, such as seagrass beds.

For example, carbon credit loans for seagrass beds and algae farms have been introduced in Changdao City, east China's Shandong Province.

China is one of the few countries in the world that has three major blue carbon ecosystems: seagrass beds, mangroves and salt marshes.

Based on global averages, the annual carbon sequestration capacity of China's three coastal blue carbon ecosystems is estimated to range from about 1.3 million to 3.1 million tonnes of carbon dioxide.

Among them, seagrass beds can sequester between 32,000 and 57,000 tonnes of carbon dioxide annually. Their role in carbon sequestration is essential for mitigating climate change.

Seagrass protection is not only the responsibility of the government and scientists; ordinary people can also get involved.

Professor Xiao states that people can raise environmental awareness, understand the ecological value of seagrass beds, and support and pay attention to seagrass protection efforts. Additionally, they can reduce marine plastic pollution and, when living by the sea or traveling to coastal areas, choose activities with minimal environmental impact, such as reducing vehicle traffic on beaches and avoiding damage to seagrass beds while snorkeling or diving.

Only through global collective efforts can we ensure the future of the seagrass, a once overlooked marine treasure.

(With input from Xinhua.)

(Cover designed by CGTN's Zhu Shangfan)