Graduated PhD 2017
Cotton Farming and N Cycling: Adaptation to Climate Change
Today, one of the most concerning issues all over the world is climate change; in particular, an 1.1 to 6.4o increase in global temperatures during 21st century and alterations in precipitation patterns are predicted by Intergovernmental Panel on Climate Change.
Many industries including cotton production have been in the consideration for their risks when facing future climate challenges and appropriate strategies to mitigate effects caused by them. Australian cotton industry which contributes 2% of world's gross cotton yield is expected to endure more frequent droughts and floods due to global warming. It is known that agricultural soils play a central role in global carbon and nitrogen cycles which will be impacted by climate change, and then this will lead to the influences on soil processes and fertility that relate directly to crop productivity and quality.
Cotton plants have been known to be dependent much on nitrogen fertilizers and water storage in order to maintain high productivity. Furthermore, nitrogen loss due to biological denitrification and nitrate leaching is indicated as a potentially threat for cotton crops. There is still a requirement to figure out more clearly the relationship between climate change and soil nitrogen and its effect on carbon sequestration by soils.
Thus, this research will investigate how increasing temperature and CO2 level together with two extreme weather events: drought and flooding impact on nitrogen cycling in cotton soil. Particularly, nitrifying and denitrifying process will be focused in terms of measuring biological activities, quantification of nitrogen functional genes and microbial community analysis by molecular approaches. The data and knowledge gained from this study will help to better understand the response of key drivers of N soil processes as well as greenhouse gas emission –N2O to altered climate.
Consequently, suitable strategies to mitigate effects of shifts in climate on cotton productivity and quality through the effective management of N fertilization will be generated.
Research Project Supervisors
Professor Brajesh Singh, Professor Ian Anderson, Professor David Tissue, Dr Michael Bange
Nguyen LTT, Broughton K, Osanai Y, Anderson IC, Bange MP, Tissue DT, Singh BK, (2019) 'Effects of elevated temperature and elevated CO2 on soil nitrification and ammonia-oxidizing microbial communities in field-grown crop', Science of the Total Environment, vol.675, pp 81-89
Nguyen LTT, Osanai Y, Anderson IC, Bange MP, Braunack M, Tissue DT, Singh BK, (2018) 'Impacts of waterlogging on soil nitrification and ammonia-oxidizing communities in farming system', Plant and Soil, vol.426, no.s 1-2, pp 299-311
Nguyen LTT, Osanai Y, Anderson IC, Bange MP, Tissue DT, Singh BK, (2018) 'Flooding and prolonged drought have differential legacy impacts on soil nitrogen cycling, microbial communities and plant productivity', Plant and Soil, vol.431, no.s 1-2, pp 371-387
Nguyen LTT, Osanai Y, Lai K, Anderson IC, Bange MP, Tissue DT, Singh BK, (2018) 'Responses of the soil microbial community to nitrogen fertilizer regimes and historical exposure to extreme weather events: Flooding or prolonged-drought', Soil Biology and Biochemistry, vol.118, pp 227-236