Ecosystem - Coastal River Bluffs Video




The impacts of past climate change are very evident on the steep, north-facing bluffs and adjacent low slopes along the major rivers that drain from the southern Appalachians such as the Chattahoochee/Appalachicola and the Savannah. Hundreds of miles away from their kin on bluffs in the Florida panhandle you can find Trillium growing with palms. Take a look around you. How many plants that you are familiar with in the Appalachians do you see? 

So how did they get here? They are generally thought to be refugees from past climates. During cold periods such as the ice-ages Appalachian species extend their range into the steamy lowlands and then when it gets warmer and drier, they retreat back to their homeland. Some were left behind in the cool microclimates and rich soils of the north-facing slopes of rivers. Many are exactly the same as those found farther north like Bloodroot and Halberd-leaf Violet. Others have changed to become unique species found today only in these isolated habitats like Ashe’s and Pyramid Magnolia but both have their closest ancestors in the Appalachian region. Plum-leaf, Alabama, and Florida Azaleas are good examples that are today “stuck” in isolated areas only in this region. A plant that grows only in one area is called an endemic, and the Chattahoochee River bluffs are extremely rich in endemics. Some of them are among the rarest species on earth. Florida Nutmeg (Torreya taxifolia) is today nearly extinct, due to a blight but was never abundant, being known from only a tiny corner of Florida and Georgia. Perhaps its roots also lie in the distant past in our mountains.