Despite covering 3% of the land surface, peatlands are the largest global terrestrial carbon sink, estimated to hold 20% of the earth's total organic carbon. Peatlands sequester carbon in the form of greenhouse gases (GHG) and carbon dioxide (CO2) through photosynthesis, emitting methane (CH4) through respiration and dissolved organic carbon (DOC) into nearby water bodies. Climate change has increased global temperatures, caused drought and fire, and altered rain patterns. Climate change can cause peatlands to shift from a carbon sink to a carbon source increasing the release of GHG into the atmosphere and surrounding water bodies as DOC. Australian alpine peatlands are heavily understudied, they are unique due to their small size, constrained to poorly drained topographic regions and are groundwater-fed ecosystems. Historically, fire has been infrequent in Australian alpine peatlands, but in the last few decades, fire has increased in this region, with peatland responses being largely unknown.
This study will focus on CO2 and CH4 fluxes in the Bogong High Plains, Victoria, Australia investigating the effect of fire on peatland GHG emissions. Two sites similar in distance, size, vegetation composition, aspect and altitude have been selected, and gas fluxes measured within three treatments (burnt, unburnt and unburnt within burnt). To consider temporal variations, environmental characteristics and GHG fluxes will be recorded fortnightly for 6 months. Five replicate flux collars will be sampled in two dominant plant communities within each treatment across sites.
Burnt peatlands are expected to emit more CO2 than CH4, while unburnt peatlands will sequester CO2 and emit CH4. Burnt peatlands will have higher actual GHG (CH4 and CO2) emissions than unburnt. This study predicts a trend in GHG emissions across the alpine growing season. An insight into peatland function and response to fire is imperative for assessing future climate change effects and aiding in mitigation.