Coastal wetland ecosystems, including saltmarsh, mangrove forests and seagrass meadows, play a crucial role in adapting and mitigating the impacts of climate change. Coastal wetlands store large amounts of carbon, also known as blue carbon, in their soils and vegetation- making them important carbon sinks.
The protection and restoration of these ecosystems can help reduce greenhouse gas emissions and enhance carbon sequestration. Measuring greenhouse gas (GHG) emissions, particularly carbon dioxide (CO₂) and methane (CH₄), from coastal wetlands is important to quantify their contribution to global GHG emissions and for understanding the impacts of human activities, such as land use change or restoration efforts, on wetland emissions.
Current options for GHG measurements make field days a slog
Dr Melissa Wartman, a Research Fellow from the Blue Carbon Lab (BCL), is collaborating with STRUT to develop a new portable and budget friendly device that can measure and record GHG emissions in the field using a closed chamber design.
“The current way we are measuring GHG requires BCL researchers to use an ‘Ultra-Portable’ Greenhouse Gas Analyzer (UGGA) weighing 20 kg, which is then plugged into to a 2.5 kg battery. Due to the nature of the terrain, carrying this equipment around our coastal wetland sites to obtain comprehensive spatial measurements can be incredibly challenging and exhausting,” said Dr Wartman.
The new device, known as Emission Reduction Measuring Instrument (ERMI), is significantly lighter and more portable weighing in at 1.5kg (including the chamber and battery). In addition to reducing weight, Dr Wartman is looking to also reduce the cost of these instruments. It can cost around $70,000+ to purchase an industry standard GHG analyser such as the UGGA. The cost of ERMI is expected to be under $5,000 per unit.
ERMI can measure both CO₂ and CH₄ GHG emissions, soil temperature, air temperature in the chamber, air pressure, and lux (amount of light hitting the chamber). ERMI has the capability to record to the cloud, in addition to an internal memory drive. ERMI can currently take 8 hours of continuous measurements before needing to be recharged by USB.
Putting ERMI through its paces
Recently, BCL researchers including Dr Wartman, Dr Noyan Yilmaz and Rory Crofts were joined by Rhys Bischof from STRUT to test ERMI against the UGGA in a saltmarsh ecosystem at the Spit Nature Reserve, near Avalon, Victoria. Currently, the results of the analysis are being studied to refine the calibration of ERMI. If successful, ERMI could provide several benefits to researchers, including reduced costs, which would make it more accessible to labs and organizations globally. In addition, with the ability to use more units simultaneously, fieldwork efforts could be expanded and accelerated, enabling faster and more comprehensive greenhouse gas analysis.
Keep an eye out for further updates on this project!