Mangroves, salt marshes, and estuaries are found all along oceanic coastlines, and all perform the necessary function of maintaining balance within the ecosystem. Many are unaware that these areas, often dismissed as worthless swamps, are filtration systems, nurseries for tiny marine animals, and important barriers against erosion. Mangroves also store atmospheric carbon at a rate about 50% greater than tropical rainforests. Let’s take a closer look at these priceless natural treasures.
Climate Change Affecting Marshes and Mangroves
Humankind has been working against nature for millennia; but during the past one hundred years or so, destruction has occurred at a faster pace than ever before. As seen in one coastal flood after another, removing these natural barriers has ultimately led to tragic destruction and the loss of human life. Now, there’s a push to restore these important natural buffers to their previous forms – but this is something that’s easier said than done.
One example of an estuary that has seen more than its fair share of damage is the Chesapeake Bay, which is the largest estuary in the United States. Mangroves in Florida have also been damaged, as have salt marshes.
Climate change is affecting salt marshes and mangroves in terms of water and atmospheric temperatures, salinity, and sea level rise. Mangroves are being affected in a different and slightly surprising way – the forests are shifting toward the north because the number of freezing periods is decreasing. Between 1984 and 2011, Florida recorded more than three thousand acres of new mangrove growth, all of which occurred north of Palm Beach County. Hard freezes below 28.4 degrees Fahrenheit typically limit mangrove growth, but cold snaps are happening less frequently in the northern portion of Florida.
Since 1980, approximately 35 percent of the planet’s mangrove forests have been destroyed. This amounts to a larger amount of destruction than that which the world’s coral reefs and tropical rainforests have been submitted to. While additional mangrove growth might seem like a beneficial side effect of climate change given that they are among the planet’s most necessary and valuable ecosystems, the shift is potentially problematic. The new mangrove forests are encroaching on salt marshes, which support different animals, birds, and fish than mangroves do. How the northward expansion will affect salt marsh species is not known for certain, but it is believed that salt marshes may also show expansion toward the north. Aquatic species that rely on cooler temperatures for survival may also migrate slowly toward the north as has been seen in other ocean populations.
Life in a changing world is uncertain. Fortunately, planners are coming to the realization that coastal marshes, mangrove forests, and estuaries are more than just dismal swamps. While keeping mangroves from becoming overgrown and preventing mosquito infestations are two important goals, preventing further destruction and bringing mangrove forests, salt marshes, and estuaries back into healthy balance is a priority. The future of these buffer zones is still unknown; however conservation means a healthier planet for all – including humanity.