The Australian sugarcane industry is a major contributor to N pollution entering the Great Barrier Reef, with recent estimates suggesting it contributes to 56% of inorganic nitrogen loads. Additionally, Sugarcane soils are Australia’s largest contributors (per area) of the potent greenhouse gas (GHG) nitrous oxide (N2O). These losses illustrate an inefficient use of costly N fertilizers by sugarcane farms. The environmental and also the agronomic consequences of N losses from sugarcane soils demand mitigation strategies aimed at reducing environmental harmful N losses while ensuring productivity in sugarcane-systems. Improving fertiliser application rates and thus avoiding excess nitrogen in the soil is an effective strategy to reduce environmental pollution, mitigate climate change, but also increase profitability.
Sugarcane is typically produced under conditions that are known to stimulate N2O formation, i.e. high fertiliser inputs, a wet and warm climate and the increasing adoption of cane trash retention as a carbon source. Recent research has shown that N2O emissions from other agro-ecosystems increase exponentially with N fertiliser inputs, but this relationship has not been confirmed for sugarcane systems. This lack of data hinders the development and evaluation of strategies optimising N fertiliser inputs to reduce N2O emissions. Such strategies need to be based on a comprehensive understanding of key factors driving N2O production in sugarcane soils, including the response of N2O emissions to different N fertiliser rates.
We will quantify GHG emission from these soils (N2O, CO2, and CH4) and link these emissions to different soil parameters in order to identify the key drivers of these emissions. This will be done in a series of laboratory incubation trials, demonstrating when and how much nitrogen is released from synthetic fertiliser, lost as N2O or immobilised by microbes in the soil. As well as learning about a variety of laboratory techniques such as ion colorimetry and gas chromatography, students will get firsthand experience in working on the frontier of environmental science in Australia.
Working as part of the M4rl Team means working in a highly qualified international team, and provides insight into interdisciplinary research. During the project, the students will undertake the following activities:
- Soil and gas sampling
- Soil preparation and analysis in modern laboratories at QUT
- Gas sampling during the experiments
- Gas analysis
- Data analysis
- Presentation of the results
This project will determine N2O response curves across different N fertiliser inputs from Australian sugarcane soils.The results will contribute to an improved process understanding of N losses and retention in sugarcane soils, helping to develop strategies to increase efficient N fertilizer use in sugarcane systems providing both environmental and agronomic benefits
Skills and experience
A basic background in soil science, environmental science, agricultural science, ecology, or related sciences is of advantage
- Experience with laboratory work is of advantage but not mandatory
- Ability to work in an international team
- Independently working and motivated
- Interested in soil science and greenhouse gas emissions from agricultural soils
Contact the supervisor for more information.