Biogeochemistry
Research Team
Dr Liz Bailey
Prof. Neil Crout
Prof. George Shaw
Dr Scott Young
Dr Sofie Sjogersten
Research Overview
Biogeochemistry is concerned primarily with measuring and modelling chemical cycling in the environment. Our focus at Nottingham is mainly on potentially hazardous trace elements (Pb, Cd, As etc) and radio-isotopes (137Cs, 90Sr, 129I) but also includes broader consideration of carbon and nitrogen dynamics and availability of (beneficial) micronutrients (Se, I, Zn) in soils and aquatic systems. Our research strategy in this field has always been to foster research links with other University departments (UK and overseas) and institutions with similar interests and complementary skills and facilities.
General Research Themes
• Iodine transformations in soils
• New approaches to measuring heavy metal reactivity in the environment
• Mobilization of potentially toxic trace elements under anaerobic conditions
• Modelling trace metal adsorption and fixation in contaminated soils
• Carbon cycling in tropical and arctic natural ecosystems
Current Projects
Using Isotopic Dilution to Quantify the Reactivity of Metals in Contaminated Soils -
Ezzat Marzouk
Developing Measurement Techniques to Establish the Availability of Metals in UK Soils –
Judith Garforth
Understanding bioavailability of iodine in soils of Northern Ireland -
Hannah Bowley
Iodine transformations in soils
The World Health Organisation estimate that 740 M people in 130 countries suffer from Iodine Deficiency Diseases. However, there is currently poor understanding of (i) the mechanisms whereby iodine that is bound to soil solids is made available to plants during the growing season and (ii) how iodine arriving in rainfall reacts with the soil and is conserved, mainly bound to soil humus. This project, in co-operation with the British Geological Survey, will model iodine cycling in soil-plant systems to aid prediction of iodine availability to plants based on rainfall inputs and soil characteristics. The model will be parameterised by measuring transfers between soil and vegetation under controlled conditions. This will involve using iodine-129 as a tracer and liquid chromatography linked to inductively coupled plasma mass spectrometry (LC-ICP-MS) to measure changes in iodine speciation through time.
Heavy Metal Solubility and Uptake
We have under taken a considerable amount of work on the bioavailability, transfer of metals in soils and their uptake by plants. A feature of the work has been the use of isotopic methods to descriminate between metals of different labilities within soil (i.e. those readily able to exchange with soil solution and those fixed in some way). Much of the modelling work has focussed on using this information to develop readily applicable models of metal solubility and plant uptake. i.e. models which can be applied with the minimum of soil and plant specific information. More recently this work has applied similar methods to the field scale testing of phyto-remediation of arable soils contaminated with metals (i.e. using plants to extract metals from soils).