A recent study by researchers from Southern Cross University has determined that coastal ecosystems, including mangroves and fjords, are significant net sinks for greenhouse gases, primarily carbon dioxide (CO2). Analyzing data from ten global regions, the researchers found that coastal ecosystems absorb vast amounts of CO2, although they also emit methane (CH4) and nitrous oxide (N2O), which partially offsets the CO2 absorption. The study highlights Southeast Asia as the most substantial sink due to its productive tropical wetlands, followed closely by North America, where fjords also contribute significantly to CO2 uptake.
Fjords, in particular, are noted for their efficiency, absorbing approximately 40% of CO2 emissions from various tidal systems. Despite coastal wetlands’ role as sources of CH4, their overall contribution results in them being net greenhouse gas sinks when considering all three gases. The findings call attention to the importance of conserving and restoring coastal habitats to enhance carbon sequestration and mitigate climate change effects. Effective management strategies could include reducing nutrient and wastewater inputs to limit greenhouse gas emissions. The research aims to inform climate policies and contribute to global carbon budgets that previously overlooked coastal ecosystem contributions.
