By Cameron Chai
A recent study published by researchers at Ohio State University’s School of Environment and Natural Resources has concluded that all the wetlands located in temperate regions hold value to the ecology as carbon sinks.
The wetlands offer coastal protection by serving as a buffer zone between waterways and land and also in the filtering of chemicals present in the water that runs off from parking lot, roads and farm fields.
The senior author of the study, Prof William Mitsch conducted extensive studies at two wetland sites at Ohio – the Gahanna wetland located in central Ohio and Old Woman Creek wetland located near Lake Erie. Wetlands have a carbon sequestration capacity far exceeding the capacity of agricultural soils and tropical rain forests. The Gahanna forested wetland area is a stagnant swamp whereas the Old Woman Creek wetland is connects Lake Erie with an agricultural watershed and receives large pulses of water from the two entry points. The soil samples were compared to study their carbon-holding capacity and the sediment depth where carbon storage had occurred in a span of 50 years.
The results of the study indicated that the stagnant Gahanna wetland showed twice the average carbon storage rate than the flow-through Old Woman Creek wetland. An average of 317 g of carbon was found per square meter for each year, significantly higher than the 140 g of carbon found in flow-through wetland areas and 15-25 g found in boreal peatlands located in Siberia and Canada. The conclusion suggested that the freshwater wetlands can aid in offsetting the greenhouse gas emissions. Prof William Mitsch appeals through this study that all wetlands receive more credit in global carbon budgets for policy considerations. Boreal peatlands wetlands located in subarctic regions, which contain organic matter are the only wetlands that have favored in policy considerations.
The wetland carbon sink study was supported by Ohio State’s School of Environment and Natural Resources, the Wilma H Schiermeier Olentangy Wetland Research Park at Ohio State, the National Science Foundation and the US Environmental Protection Agency.