The Unseen Importance of Seagrass in Carbon Storage and Ecosystem Support
Hidden beneath the ocean’s surface, seagrass plays a crucial role in supporting marine ecosystems and combating climate change. Despite its significance, it has not been consistently monitored until recently. Researchers from Arizona State University have embarked on a groundbreaking study to map seagrass fields worldwide.
Seagrass, unlike seaweed, is an aquatic plant with roots akin to terrestrial plants. It serves multiple ecological functions such as preventing shoreline erosion, filtering ocean water, and storing carbon. The research aims to shed light on how these underwater meadows contribute to coastal restoration and the broader carbon cycle.
Described as an underwater rainforest, seagrass meadows have been under-researched compared to coral reefs. “There’s a missing piece for that. So people pay attention a lot on coral reefs, but seagrass is actually very, very important. It can cohabitate with coral reefs, building the food chains,” stated Jiwei Li, an ASU professor and one of the study’s authors.
Seagrass absorbs and stores carbon, not just within its blades but significantly more within the sediment beneath it. As Li explained, “The sediment of seagrass stores much more carbon than the seagrass itself.” This sediment functions similarly to soil, capturing carbon that would otherwise contribute to atmospheric carbon levels.
The global map produced by the study estimates that seagrass fields store carbon equivalent to the emissions from 500 million cars annually. However, due to observational constraints, this figure may be conservative. Li noted the disparity in data collection, “We know the height of forests, we know the biomass of forests, we know how many species. But for seagrass, we actually just know how many seagrass meadows are actually there.”
Future research aims to delve deeper into the diversity and density of seagrass species, enhancing our understanding of their ecological roles and interactions with carbon reservoirs. This knowledge could be pivotal in informing conservation and restoration projects along coastlines.
