Earth Today | New study provides insights into mangrove conservation
Published:Thursday | August 17, 2023 | 12:07 AM
A NEW study from the United Nations Food and Agriculture Organization (FAO) has offered some key insights into the future conservation of mangroves, which are counted among the world’s most productive ecosystems and important carbon sinks.
In carrying out their function as carbon sinks, mangroves absorb carbon dioxide from the atmosphere – a service that is considered especially valuable, given the pressing realities of climate change, which is fuelled by human consumption of greenhouse gas (GHG) emissions, including carbon dioxide from, for example, coal burning and the operation of the transportation sector.
The report – titled The World’s Mangroves: 2000- 2020, notes, among other things, that “mangrove restoration should be given priority in global, regional and national restoration initiatives in view of their crucial benefits for livelihoods, coastal resilience and biodiversity conservation”.
“Mangrove restoration, sustainable use and conservation should be further emphasised in nationally determined contributions (NDCs) and in climate-change mitigation strategies in general, given the importance of mangroves as carbon inks and the co-benefits of adaptation and disaster risk reduction,” the report added.
NDCs are individually tailored plans for countries that are signatories to the Paris Agreement to reduce their emissions of GHGs. The Paris Agreement, which is the legally binding global treaty on climate change, has seen countries committing to “holding the increase in the global average temperature to well below two degrees Celsius above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 degrees Celsius above pre-industrial levels, recognising that this would significantly reduce the risks and impacts of climate change”.
Meanwhile, the FAO report has noted that there is some good news for mangroves, and on which countries can build.
“The rate of net global mangrove loss slowed between 2000 and 2010 and 2010 and 2020, with the net loss of mangrove area decreasing by 44 per cent between the two periods, from 18.2 thousand ha per year in 2000-2010 to 10.2 thousand ha per year in 2010-2020,” it said.
“Accordingly, the annual rate of mangrove loss globally declined from 0.12 per cent in 2000-2020 to 0.07 per cent in 2010-2020. Of the regions, Asia accounted for 68 per cent of global mangrove area loss in 2000-2010 and for 54 per cent of the loss in 2010-2020. Of the global mangrove area gains, 47 per cent in 2000-2010 and 54 per cent in 2010-2020 were in Asia,” the report explained.
The loss experienced was due mainly to “aquaculture development (27 per cent) and natural retraction (26 per cent), followed by conversion to oil palm (eight per cent), rice cultivation (eight per cent) and other forms of agriculture (12 per cent)”.
Natural retraction, the report noted, is the likely result of climate change impacts.
“Climate change can affect mangroves in various ways, including through sea-level rise; increases in atmospheric carbon dioxide; rises in temperature; changes in rainfall; and the predicted increase in the frequency and severity of extreme weather,” it said.
“The climate-change-driven loss of mangroves further exposes vulnerable local communities to disasters, such as storm surges, floods and tsunamis –against which healthy mangroves provide a certain level of protection – resulting in a negative feedback loop,” it added.
Of note, according to the report, is that the area of mangroves lost to natural disasters increased threefold between the two periods of 2000-2010 and 2010-2020, and this trend is expected to worsen.
It is against this background that the report has suggested that the contributions of climate change impacts should also be “monitored carefully”.
“Given the ability of mangroves to naturally colonise suitable habitats, mangrove restoration should focus on creating conducive biophysical and social conditions for the re-establishment and growth of healthy mangrove forests,” it said further.
Not only are mangroves an important home for a variety of species, they also support food production, provide fibre and fuels, alongside cultural services and coastal stabilisation.