Supervisor

Rebecca Hood-Nowotny, https://orcid.org/0000-0002-4398-3233

Content

Development of chemical techniques to assess risk to water bodies from the application EOMs to agricultural soils.

Skills and Qualifications

  • Required: Masters or other equivalent university degree (e.g. 2:1 in B.Sc.) in environmental science, soil science, analytical chemistry, biology, limnology, chemistry or biochemistry, or other degree with a strong chemistry focus.
  • Desirable: Laboratory experience and using chemical methods. Well organized, keen to learn, English knowledge. Evidence of good writing and presentation skills.

 

Introduction/background

Sustainable intensification requires innovative approaches to increase productivity on existing agricultural land without negative impacts on soils and waters. The Green Deal suggests there should be an increased focus on the application of external organic amendments (EOMs) derived from the circular economy. Current models for nutrient cycling from EOMs are insufficient as they often neglect new scientific paradigms including soil microbial interactions, and the role of dissolved organic nitrogen and carbon in water. Having pioneered analytical techniques to measure plant N uptake from EOMs and investigate organic N cycling in soil we will expand on this research to underpin existing models, using stable isotope approaches and bespoke laboratory methods. These in-depth studies will allow us to predict the agronomic outcomes, nutrient losses, and potential pollution impacts of EOMs on groundwater and river water quality.

Main objective/research question/hypothesis

The PhD will examine both the terrestrial processes as well as the resulting impact on streams and groundwater. A suite of analytical and isotopic methods will be developed to predict N, P and C release from EOMs applied to soils, plant nutrient uptake, and threats to stream water and groundwater quality from a range of EOM’s. The PhD topic will cooperate with PhD topic 12 and will collectively contribute to advances in method development to study C:N:P ratios and transboundary fluxes. The following research questions will be addressed: What is the role of dissolved organic N, P & C and microbial cycling in predicting the environmental fate and plant nutrient uptake of EOM derived nutrients? Can we identify hydrologically relevant parameters that allow rapid assessment of pollution risks? How do EOMs influence the adjacent stream water and groundwater quality?

Approach/methods and time frame (Sites, areas, region of investigation)

We will use isotopic tracers to study the fate and turnover of EOM nitrogen and carbon in to soils and relevant inorganic and organic C and N pools that are transported into streams and groundwater. Baseline experiments will be carried out in the laboratory and glasshouse to select relevant and easily measurable EOMs and soil chemical parameters, such as dissolved organic carbon & mineralization potential, suitable for inclusion in models (Paper 1&2). We will graduate to field studies in which will investigate the movement and turnover of vulnerable EOM compounds in ground water and river systems (Paper 3&4). Year 4 will be focus on wrapping up the study and writing the publications for the final thesis. We foresee that the candidate will gain a vast amount of expertise and experience in isotope ratio mass spectrometry, use of isotope lasers, environmental sampling-field work and use of robotics for sample analysis. We offer a state of the are the art stable isotope and environmental science laboratory, a friendly approachable and international English language environment to work in. There will also be opportunity for an extended research exchange, in a country abroad.