“Linking microbially mediated soil organic matter turnover to N availability in agricultural soils”
We seek a highly motivated and able candidate to undertake a PhD project in soil microbiology that will build on an existing research programme addressing questions around the release of nutrients from soil organic matter (SOM).
Managing nitrogen (N) and carbon (C) resources in soil is critical for environmental and agronomic sustainability, and underpins efforts to meet global challenges of increasing food production and climate change mitigation. Microorganisms drive the majority of biogeochemical processes in soil. By understanding how these organisms function there is great potential to manage soils in such a way as to link the cycling of nutrients to plant growth, thereby decreasing economic costs associated with fertiliser application, while reducing deleterious environmental losses of N and C. SOM is the principal store of nutrients required by plants, but supply of these nutrients into plant-available forms is dependent on microbial processes.
Application of stable isotope approaches has shown that plant-derived C-flow to soil can alter rates of SOM mineralization. Further, it has been found that root exudation results in a directed response of the microbial community to mobilise N-rich components of SOM. Potentially, this represents a key mechanism by which plant productivity can be coupled with soil nutrient cycling. However, currently we do not know which microorganisms mediate the process, which activities (e.g. enzyme production) are responsible, and the extent to which microbial community composition and activity interact with soil physicochemical constraints to define nutrient cycling rates in soils.
This project will use established stable isotope approaches to quantify biogeochemical process rates in soil, as a function of plant-derived inputs, and concurrently apply metagenomics, metatranscriptomic, and metaproteomic approaches to identify the mechanisms and microorganisms responsible for mineralisation. The impact of soil type and agronomic management on the interaction will be explored. This project brings together the complementary resources and expertise sets of the three participating institutes (Teagasc (Ireland), the James Hutton Institute (Scotland) and NUI Galway (Ireland)), and will provide valuable multidisciplinary training and research opportunities in soil microbiology, soil chemistry, environmental science, agronomy and bioinformatics. The student will join a successful research group, and lively graduate training communities, and will also receive training in other aspects of scientific work, e.g. result dissemination, writing for publication and conference presentations.
Applications are invited from graduates holding at least a 2.1 class honours degree or M.Sc. in Microbiology, Soil Science or related discipline. Prior experience in molecular ecology or soil microbiology would be advantageous. A full driving licence and fluency in English are essential.
The PhD Fellowship is a joint research project between Teagasc, NUI Galway and the James Hutton Institute. Supervision will be provided by Dr Fiona Brennan (Teagasc), Dr David Wall (Teagasc), Dr Eric Paterson (The James Hutton Institute) and Dr Florence Abram (NUI Galway). The fellowship funding is €22,000 per annum and includes University fees of up to a maximum of €6,000 per annum and is tenable for 4 years.
Dr Fiona Brennan, Phone: +353 53 9171332; email: firstname.lastname@example.org
Applicants should submit a CV (including the names of two referees) and covering letter detailing their qualifications, research experience and motivation to: Fiona Brennan (email@example.com)