Nitrous oxide and methane emission from sugar cane and mangrove communities in coastal Queensland • back to student info   Diane Allen*, Dr. Susanne Schmidt* *School of Integrative Biology-Botany, The University of Queensland, Brisbane, Australia 4072 Dr Heinz Rennenberg, University of Freiburg, Germany Industry Partners: Dr Ram Dalal, Department of Natural Resources & Mines Dr Graham Kingston, Bureau of Sugar Experimental Station d.allen@uq.edu.au Nitrous oxide and methane emission from sugar cane and mangrove communities in coastal Queensland Mangrove forests and sugarcane fields are often waterlogged, have high N inputs from pollution or fertilization, and occur in tropical climates. These conditions are conducive to the production of greenhouse gases nitrous oxide (N2O) and methane (CH4). Indeed, preliminary research on mangrove and sugarcane communities in subtropical and tropical Queensland has shown that mangrove ecosystems may be significant sources for N2O and CH4, while sugarcane fields can be sources of N2O, but sinks for CO2 and CH4. Large temporal and spatial variability exists in N2O and CH4 production within mangrove ecosystems and sugarcane fields. The lack of seasonal data in relation to environmental factors and management strategies highlights the need for research that accurately quantifies trace gas fluxes and associated processes in both communities. The aim of my phd project is to determine whether mangrove ecosystems in SE Queensland are significant sources of greenhouse gases N2O and CH4. Mangrove sites with different nutrient loads will be monitored throughout a one year period, and N2O and CH4 emission will be examined in relation to nitrogen load and tidal flow. Transects from the tidal fringe to the forest will observe whether tidal inundation and frequency affect emission rates. Sediment and water nutrient loads will be measured to monitor seasonal nutrient input. The role of mangrove trees for N2O and CH4 emissions will be studied by determining emission rates from pneumatophores and prop roots in relation to water, sediment and tree nitrogen status. N2O and CH4 relations will be studied at a sugarcane farm subject to different nitrogen fertilization and irrigation strategies. Destructive biomass sampling on six occasions between 50 to 250 days after commencement of the experiment will quantify carbon and nitrogen relations of plants. This study addresses the current challenge addressing greenhouse gas relations and for improving the health of coastal environments. The study aims to improve our knowledge of greenhouse gas relations in little studied tropical plant communities and to devise improved management strategies for these systems.