Written by: Jalal Tarazi – UWCT Secondary Science Teacher
What is a “mangrove” forest?
According to the US National Ocean Service, mangroves are a group of trees and shrubs that live in the coastal intertidal zone. There are about 80 different species of mangrove trees. All of these trees grow in areas with low-oxygen soil, where slow-moving waters allow fine sediments to accumulate. Mangrove forests only grow at tropical and subtropical latitudes near the equator because they cannot withstand freezing temperatures. This makes Phuket a great home for mangroves!
Despite Phuket being a naturally wonderful habitat for mangroves, by the mid 20th century, over half of Phuket’s mangrove forests had been cut down for myriad reasons. The forests were seen as muddy places, which were breeding grounds for mosquitoes. Mangrove wood is extremely useful due to its flexibility as a building material and as charcoal. Mangrove forests were also cut down to create beach-side housing. And lastly, and most significantly, the mangrove forests were cut down to create shrimp farms. However, as Phuket and the rest of the world found out, mangrove forests are essential to coastal ecology.
Mangroves are a habitat for many species and nurseries for many more. Many of these species are economically important such as crabs, fish, and molluscs. Mangrove forests are also ideal bird migratory routes and need to be protected internationally to keep bird populations from collapsing. Mangrove forests have always been known to sequester (trap) more carbon than other forests because of the amount of carbon that can be stored in their muddy soils. In 2018, according to the Global Forest Reporting Network, they believe that mangrove forests can sequester as much as four times more carbon than other global forests!
These forests are also essential to the land/sea connection. They trap sediment and pollution coming from the land before they reach open water. This is important to protect coral reefs. Coral reefs thrive best in clear water with a very low level of nutrients, which would otherwise allow for algal growth.Lastly, and probably most importantly, mangroves act as shields against wave action from tsunamis and cyclones. New Scientist released an article in 2014 stating that mangrove forests could reduce the damage of wave action from tsunamis and cyclones by 90%! With the impacts of climate change being seen throughout the world, these ecosystems are essential to protect and reforest.
Planting Mangrove Saplings at UWCT
When Kru Jalal joined the school in 2013, he was already very seasoned in getting students to help reforest in Thailand. During his time at Thai-Chinese International School, he was able to connect with the Plant A Tree Today (PATT) Foundation in Bangkok. PATT is a non-profit organisation, which was based out of the UK and Thailand. It works on planting trees in dryland forests in Khao Yai National Park and in mangrove forests along the coast of the Gulf of Thailand.
On joining the school community, Kru Jalal was lucky enough to meet Garry Kirkland, a parent at the school and also the Project Manager at JW Marriott involved in many sustainability partnerships throughout Phuket. For the first several planting trips that the school took part in, Garry would help contact staff at the Department of Marine and Coastal Resources to help us with the planting site. The staff would select the site, bring approximately 1,000 mangrove sapling, clean the site for the debris, and use wooden sticks to mark where the saplings would be planted. Since mangroves survive in muddy soil near the ocean, there was no need to dig and planting 1,000 mangroves took much less time than one would expect.
On becoming a member of the UWC movement, sustainability continued to be part of the school’s mission. Over time, UWCT developed a strong relationship with the Department of Marine and Coastal Resources and together they set up planting trips throughout the school year.
Over the past five years, students and staff have taken part in about 15 mangrove planting trips, and have consequently planted 15,000 mangrove saplings during this time.
The school has continued to support this initiative because of its utmost importance to the future of Phuket. We have planted at several sites since this project began. Our major site was in Mak Prok, which is just directly east of the airport on the Eastern side of Phuket. Over the past five years, every planted mangrove sapling has been planted by the hands of UWCT students and staff and the area is completed reforested. We are also planting in two sites near Ao Po Marina.
The MANTA Mangrove CCA has been supported by many students over the years and invaluable teachers such as Kru Ned, Kru Len, Kru Aloni, Kru Heidi Oxley, and Kru Chris Lahey. We are excited that we built a mangrove nursery on campus four years ago and the project remains sustainable to this day, with incredible assistance from Kru Ned and his 4th-grade class. Mangrove seed pods are collected by students and staff and these pods are added to soil in bags and added to our nursery, which uses a pump with a timer to mimic tidal activity. We estimate that 20-30% of the mangrove seedlings that we planted around Phuket came from our own nursery.