Freshwater Ecosystems: Carbon Sequestration Champions

Abstract

Nature helps us fight climate change by removing carbon from the atmosphere and storing it underground—a process called carbon sequestration. Some freshwater ecosystems, like lakes, are great at carbon sequestration. Surprisingly, small organisms play a big role here! When tiny algae and bacteria in the water photosynthesize, they take carbon dioxide from the atmosphere and convert it to organic carbon (the carbon that forms all living organisms). The organic carbon moves through the ecosystem as it is eaten by other organisms or as it sinks to the bottom as either poop or the remains of dead organisms. When organic carbon reaches the bottom, it can remain buried for a long time. Aquatic plants and material from land that washes into freshwater can also sink and end up as sequestered carbon. It seems like freshwater ecosystems sequester carbon more efficiently than other environments, but scientists still have more work to do. Because of the huge diversity of water bodies across the world, scientists need to know which are the real carbon sequestration champions.