Opinion | Cherish our mangroves

By Dr. Kevin Lau

Recently, I went to Lantau Island with my family to have lunch and buy seafood. Afterwards, we visited the mangroves at the Wetland Park. Witnessing the remarkable adaptability of the animals and plants there, I couldn't help but be amazed. Mangroves are a natural treasure in Hong Kong. This ecosystem not only provides food for numerous marine organisms but also serves as a habitat and breeding ground for various fish, crabs, shrimp, and other animals. However, its importance goes beyond that. Within the entire coastal ecosystem, mangroves also protect coastal areas from storm surges and wave impacts, while absorbing carbon dioxide and other greenhouse gases.

The significance of mangroves can be compared to that of coral reefs and seagrasses. They form an interdependent ecosystem. Mangroves provide breeding grounds for many juvenile fish and crabs, including the commercially valuable species we often consume. Without mangroves, coral reefs and seagrasses would struggle to reproduce, and the marine food chain would be greatly affected.

We may underestimate the importance of mangroves. The roots of mangrove plants can create friction with incoming waves, reducing wave height and energy. These roots also allow sediments to settle, forming new land surfaces. Therefore, healthy mangroves can protect the living environment of coastal areas.

Since mangroves are so important, shouldn't we cherish them? Yes, urban development is necessary, but we should not always sacrifice mangroves for it. In the past, large areas of mangroves were cleared during coastal development and infrastructure construction. Now, the remaining mangroves in Hong Kong are fragmented. If the mangrove area continues to shrink, their effectiveness in the ecological environment becomes uncertain.

As for the existing mangroves, they are also periodically affected by heavy metals and microplastic pollution. Studies have found that Hong Kong's mangroves contain a large amount of heavy metals. While trees may develop physiological adaptations to cope with these metals, crabs and other marine organisms inevitably accumulate these pollutants in their bodies, which is concerning. In my opinion, we should cherish Hong Kong's mangroves. We can start by reducing our use of plastics to prevent plastic pollution from harming young trees or entering the food chain of mangrove organisms.

The author is a specialist in radiology with a Master of Public Health from the University of Hong Kong, and an adviser of Our Hong Kong Foundation.

The views do not necessarily reflect those of DotDotNews.