WHOLE SYSTEM CARBON CYCLING DURING THE GROWING SEASON OF A SUGARCANE CROP IN THE TWEED VALLEY

ENHANCING CARBON SEQUESTRATION and improving the sustainability of agro-ecosystems has become an increasingly important focus of management practices in the context of climate change. Given the high productivity of sugarcane, there is potential for sugarcane crops to remove large amounts of carbon dioxide (CO2) from the atmosphere and add organic carbon to agricultural soils. However, there are many concerns still regarding the impact croplands have on the carbon cycle and whether they act as a carbon source to the atmosphere. Analysis of net ecosystem exchange of CO2 and methane (CH4) provides a direct measure of carbon cycling in agricultural ecosystems. However, some Australian sugarcane farms have been developed on coastal floodplains and wetlands, containing an aquatic pathway for carbon loss via artificial drains that has not been quantified before. Comprehensive accounting of all carbon pathways is therefore required to quantify the whole system carbon balance and determine the sink or source capacity of agricultural floodplains used for sugarcane plantation.