PHD Project

January 16, 2017

Whodunnit? An isotopic fingerprint to identify phosphorus sources and cycling in catchments

Whodunnit An isotopic fingerprint to identify phosphorus sources and cycling in catchments 400 x 400 px

This studentship offers you the opportunity to work with scientists across the UK to develop a new isotope tracer for the element phosphorus (P). Phosphorus is critical for life, being integral to the structure and function of key biomolecules including DNA and cell membranes.

Therefore, P is both an essential element that supports food production and a key contributor to eutrophication, leading for example to algal blooms in surface waters. This creates a dilemma that requires us to understand the relative importance of different sources of P, including agriculture and waste water, and the role of these sources within aquatic and terrestrial ecosystems. This studentship will focus on a novel technique to provide this understanding.

You will develop a stable isotope tracer for phosphate in soils and waters. Stable isotopes have been successfully used for other nutrients in the environment, including nitrogen, but the P atom has only one stable isotope. However, by focussing on the phosphate ion (PO4), the stable isotopes of oxygen in phosphate (δ18OP) can be analysed to understand the sources and cycling of P. Developing and applying the δ18OP tracer is the basis for this studentship, which aims to:

1) Characterise δ18OP within both point and diffuse sources of P in catchments including mineral fertiliser and soil, alongside the temporal variability in δ18OP.

2) Track changes in δ18OP as P is cycled through soil-water systems across laboratory/lysimeter, field, and catchment scales.

The project will be based at Rothamsted Research North Wyke where the student will interact with researchers and other students to undertake both laboratory and field work. Supervisors at Lancaster University and the British Geological Survey will provide training in advanced laboratory techniques, including isotope and NMR analysis. There will also be opportunities to take advantage of strong links between the supervisory team and international collaborators in China, Panama and Switzerland.

Eligibility: Applicants should hold a minimum UK Honours Degree at 2:1 level or equivalent in subjects such as Environmental Science, Environmental Chemistry, Agricultural Sciences or Natural Sciences. Experience of laboratory analyses and basic laboratory techniques is essential. For further details please contact Dr Martin Blackwell (

January 16, 2017 2015