Halt, Reverse, Protect

The report hopes to present a clear and simple cost-benefit analysis to policymakers to show that for three key issues that face coastal populations, a mission of “halt loss, restore half, double protection,” is the most effective and achievable strategy available.

Conservation outlet Mongabay reporting on the summary detailed that in the aftermath of the December 2004 tsunami that killed 200,000 people across Asia, Sri Lankan researchers estimated that per hectare per household, mangroves, which Sri Lanka had very little of back in 2004, confer $14,500 in economic value, in part because they can absorb 70-90% of the kinetic energy of a tsunami wave.

The State of the Mangrove 2022 estimates that coastal communities near mangroves around the world enjoy protections of property and real estate equal to around $65 billion through this protection from storms and waves.

For this and for other reasons, the report recommends countries and partners work to halt the loss of mangroves entirely, restore half of what was lost since 1996, which equates to some 4,092 km2 of restoration, and double the area of mangroves protected worldwide by about 61,000 km2.

With the addition of the new maps, the report has identified around 8,100 km2 of mangroves that can be restored, with a particular focus on Southeast Asia and in countries like Papua New Guinea, Indonesia, and others, where much of the world’s mangroves can be found.

The goods

Worldwide, around 4.1 million working fishermen, the report estimates, rely on mangroves to act as nurseries for all manner of creatures. The executive summary claims that more than 600 billion shrimp and fish, and 100 billion bivalves and crustaceans are brought up every year in mangrove forests.

Mangroves are critical to an estimated 893,000 small-scale fishers in Indonesia alone, while an estimated 82% and 89% of fishers in Bangladesh and Nigeria respectively fish predominantly in and around mangroves.

But in the halls of power around the world, what will likely evolve to become the real value of mangroves is their potential power for storing carbon. Based on the chemical, geological, and biological reality of growing in waterlogged soil, mangroves are estimated to hold up to four times the amount of carbon as some other forested ecosystems.

Mangrove soils worldwide store the equivalent of 22.86 gigatons of CO2, or around 6.23 gigatons of soil carbon. This is more than half of what the human population currently emits every year.

“The loss of even just 1% of remaining mangroves could lead to the loss of 0.23 gigatons of CO2 equivalent, equating to over 520 million barrels of oil, or the annual emissions of 49 million cars in the US,” the authors write.

For this reason, the protection recommendations for an additional half of all mangrove forests is critical. The report’s recommended restoration size would store another 1.27 gigatons of CO2 equivalent.

Some of the largest restoration programs going on in the world right now include Senegal, where in the regions of Casamance and Sine Saloum, 80 km2 has so far been reforested, totaling nearly 80 million trees, and Indonesia, where President Joko Widodo has attempted to reforest 6,000 km2. China has successfully restored 4 km2 of mangrove forests, totaling around 4 million trees, in Zhanjian, Guangdong province. WaL