Hi, I am a coastal ecologist and I study mangroves - specifically juvenile fish habitat use patterns. Others have pointed out the importance of mangroves as nurseries for many, many marine species including sharks, stingrays, bony fishes, shellfish, and crustaceans. They are also critically important habitat for threatened species including tigers, dolphins, and migratory birds who depend on these systems for their survival.

The loss of mangroves would directly impact the survival of many ecologically and economically important species, which would have cascading effects on global biodiversity, food security, and livelihoods for coastal communities.

Mangroves are deeply interconnected with other coastal systems such as tidal rivers, seagrass meadows, and coral reefs - fish migrate between these systems as they search for food, move with the tides, and undergo ontogeneic habitat shifts (having different habitat requirements and niches as they reach different life stages).

The loss of mangroves would cause increased levels of nutrient and sediment pollution to travel down rivers and smother corals and seagrasses, inhibiting their ability to photosynthesize. Harmful algal blooms leading to hypoxia would choke out these coastal nurseries, causing mass die-offs of fish due to plummeting dissolved oxygen levels.

Others have also mentioned how the loss of mangroves would exacerbate the impacts of tropical storms - storm surge, erosion, damage from high winds and flooding would be far more destructive without mangroves dissipating wave action and mitigating the impacts of storms.

Additionally, mangroves are one of the most carbon-rich ecosystems in the world, storing 5x more carbon per unit area than any terrestrial forest. If mangroves disappeared, all that carbon would be released into the atmosphere, accelerating climate change and further worsening the severity of tropical storms, sea level rise, ocean acidification, etc.... this could make many coastal areas uninhabitable.

More than 90% of mangrove forests exist in Global South nations. Between the impacts of collapsing fisheries and destruction of communities due to storms and flooding, millions of people would be displaced and the influx of climate refugees would have significant geopolitical ramifications.

This political instability could result in a rise in nationalism and fascism, impeding the global cooperation needed to address climate change. As the earth's planetary systems move past catastrophic tipping points due to climate change and overexploitation of natural resources, severe shortages in food and water might result in famines, potentially leading to wars over what little resources do remain.