News day reporter
Director (Ag)/ Wetland Ecologist,
Institute of Maritime Affairs
Our coasts, especially the Gulf of Paria, were once lined with tall trees upheld by massive, tangled roots beaming with wild animals, where our grandfathers and fathers hunted crabs to put in the Sunday callaloo and harvested oysters that were sold in spicy sauce around Reine Parks Savannah. At the time, we did not fully understand or appreciate the importance of these coastal forests, so up to 50% was cleared to build homes, businesses and ports. What are you talking about, you ask me? These are our mangrove forests.
Mangrove forests are spectacular and prolific ecosystems located at the boundary between land and sea. Mangroves are salt-tolerant trees, also called halophytes, which are adapted to life in harsh coastal conditions. They contain a complex salt filtration system and intricate root system to cope with saltwater immersion and wave action, and are suited to the low oxygen conditions of sea-soaked mud. water.
Lately, we have learned more about the value of mangrove forests. Mangroves provide essential ecosystem services, contributing an estimated US$42 billion to global fisheries, storing 25.5 million tonnes of carbon annually, and providing flood protection to over 15 million people annually (Walker et al 2022). These forests act as an important environmental barrier between shorelines and land, protecting the ecological and social communities of the inhabitants from the adverse effects of extreme events, such as hurricanes and storms around the world.
Mangroves have a significant effect on the extent of flooding and coastal flood damage. It is estimated that if all the mangroves in the world were to disappear, an additional 18 million people would be flooded each year on average, an increase of nearly 40%, and the annual property damage would increase by US$82 billion.
A 2019 World Bank study pegs the annual value of Jamaica’s mangrove forests for flood risk reduction to the country’s built capital at over $2,500 per hectare per year. In Trinidad, floods are the most common and widespread of all natural disasters and there is strong evidence that, in a warming world, destructive floods will become more frequent and intense, affecting the lives of even more of people.
In addition to providing protection from coastal flooding, mangrove forests have the highest carbon capture and storage rates of any other ecosystem, terrestrial or marine, contributing disproportionately as carbon sinks, if they are not disturbed. On average, mangroves have an average ecosystem-wide carbon stock of about 950 t C ha−1, which is about 2.5 to 5 times higher than the average carbon stock of the entire ecosystem. ecosystem found in tropical temperate, boreal and upland forests (200–400 t C ha −1) (Alongi, 2012).
Initial estimates of carbon stored in aboveground biomass of TT mangrove forests are 809,085.92 tonnes. Comparing mangrove forest carbon to terrestrial forest carbon revealed that per hectare, mangrove forests store 61% more carbon than terrestrial forests in Tobago, while for Trinidad the value was 44% (Juman et al 2021). Clearly, there can be a major climate benefit from slowing the rate of conversion of mangroves.
In TT, mangrove forests also provide livelihoods for people who harvest and sell fish and shellfish; the most important economically is the harvesting and trade of hairy crab, blue crab and mangrove oyster. Many also make a living as tour guides, as the mangrove forest provides invaluable opportunities for recreation and tourism. They are important tourist destinations due to their aesthetic value and high biodiversity. The Caroni Swamp is one of Trinidad’s most popular ecotourism sites. It is particularly popular with bird watchers due to its rich bird population, and tour guides have made a living from the marsh for generations.
Despite their key role in helping to cope with climate change and providing livelihood opportunities, mangrove forests continue to be degraded by human activities. Mangrove deforestation is subject to a host of socio-ecological factors, ranging from climate change (e.g. increased salinity due to rising temperatures and natural disasters – tropical cyclones and tsunamis) to pollution and anthropogenic exploitation (encroachment, exploitation of forest resources, water abstraction, urbanization and upstream pollution) (Walker et al 2022).
In commemoration of the International Day for the Conservation of the Mangrove Ecosystem, July 26, let us all reflect on the crucial role that our mangrove forests play in our daily lives, in our diet, our culture, our way of life. At the Institute of Marine Affairs (IMA), we will continue to conduct research and monitor mangrove forests to provide the science needed to effectively manage and restore these critical ecosystems so they can continue to provide ecosystem services. to all citizens of our beautiful island state. Work with us to conserve our mangroves!
OnlineAlongi, D (2012). Carbon sequestration in mangrove forests. Carbon Management 3(3), 313–322.
Juman, R, Asmath, H, Gooding, N, and Collins, G. 2021. Mangrove Forests of Trinidad and Tobago, Institute of Marine Affairs, Chaguaramas, Trinidad and Tobago
Walker, JE, Ankersen, T., Barchiesi, S., Meyer, CK, Altieri, AH, Osborne, TZ and Angelini, C., 2022. Governance and the mangrove commons: Advancing the cross-scale, nested framework for the global conservation and wise use of mangroves. Journal of Environmental Management, 312, p.114823.
World Bank. 2019. “Forces of Nature: Valuation and Economic Valuation of Coastal Protection Services Provided by Mangroves in Jamaica”