Global climate change caused by anthropogenic carbon emissions is of major concern, and more information on how much carbon is being stored within and emitted from different ecosystems is urgently required, both to enhance future climate predictions and to implement robust carbon mitigation measures. With 75% of Northern Ireland’s area being covered by farmland, farm soils could potentially form a large carbon sink. However, reliable data on how fast carbon is being buried in soils of farms compared to other types of land use such as urban parks or gold course land, and on how long C is buried for, remain lacking. Moreover, existing 14C-based estimates (e.g., Fornara et al. 2020) often contradict those based on Earth system models (Shi et al. 2020).This research project will investigate how different land uses affect carbon burial rates and its long-term retention.
The student will take radiocarbon measurements on multiple soil levels in a range of Northern Irish fields, to assess the long-term burial of different forms of carbon within soils. Different soil components (e.g. bulk, homogenized, mechanically vs. chemically separated, and any identifiable plant remains) will be subjected to a range of pretreatments and 14C dated in order to assess how long ‘mobile’ and ‘recalcitrant’ forms of carbon persist in different types of soils. This project is part of a wider large-scale project led by the Agri-Food and Biosciences Institute of Northern Ireland (AFBI-NI), which will sample and analyse soils from thousands of farms across Northern Ireland to produce tailored management plans regarding nutrients, water quality, air quality and carbon (see https://www.bbc.co.uk/news/uk-northern-ireland-61100707 and https://www.afbini.gov.uk/news/soil-nutrient-health-scheme-project-launched).
This project will provide exciting opportunities for research students to use the latest laboratory techniques in order to help answer essential questions regarding carbon sequestration rates in soils across Northern Ireland, and as part of the larger project make real contributions toward understanding the effect of land use on C sequestration and burial rates, and to promote approaches that will enhance land use.
Essential & desirable candidate skills
Essential: A good background in either Geography, Palaeoecology, Ecology, Biochemistry, Geology or Civil and Environmental Engineering
Desirable: Experience with laboratory and fieldwork
|Profile: Maarten Blaauw|
Institution: Queen's University, Belfast
Department/School: School of Natural and Built Environment
|Profile: Dmitri Mauquoy|
Institution: University of Aberdeen
Department/School: School of Geosciences
Dr Jonathan Holland
AFBI, Agri-Environment Branch
Fornara, D., Olave, R., Higgins, A., 2020. Evidence of low response of soil carbon stocks to grassland intensification. Agriculture, Ecosystems and Environment 287, 106705.
Shi, S., Allison, S.D., He, Y., Levine, O.A., Hoyt, A.M., Beem-Miller, J., Zhu, Q., Wieder, W.R., Trubmore, S., Randerson, J.T., 2020. The age distribution of global soil carbon inferred from radiocarbon measurements. Nature Geoscience 13, 555–559.
Trumbore, S., 2009. Radiocarbon and soil carbon dynamics. Annual Review of Earth and Planetary Sciences 37–66.
This project will make heavy use of laboratory techniques. The student will receive training in the preparation and measurement of soil samples, which will be performed on the latest generation IonPlus MICADAS 14C accelerator mass spectrometer. Depending on student interests and on the project development, different techniques will be applied to the soil samples, and this could include the pretreatment (in AFBI and/or at the 14CHRONO Centre, Queen’s University Belfast) use of recently installed equipment for the graphitization of samples pretreated using a range of protocols, gas 14C counting of small samples, ramped pyrolysis/oxidation to separate thermally labile carbon fractions from more stable ones based on the temperature at which they are released, IRMS measurement of stable isotopes, and/or 210Pb dating of vertical sequences of samples through alpha counting. Experience with fieldwork and laboratory techniques would be an advantage, but training in the usage of the above techniques will be provided as necessary.
Expected Training Provision
Experience with fieldwork and laboratory techniques would be an advantage, but training in the usage of the above techniques will be provided as necessary.
The potential for enhanced carbon sequestration in farmlands is large, especially given the fact that c. 75% of Northern Ireland is agricultural, and given the urgent need to find ways to mitigate carbon emissions through carbon burial. Given the embedding of the research within the larger-scale AFBI soils project, this PhD project could potentially contribute to enhanced management strategies of individual Northern Irish farms, as well as to impact future policy.
The student will be supervised by Dr. Maarten Blaauw (1st supervisor, School of Natural and Built Environment, Queen’s University Belfast), Dr. Dmitri Mauquoy (2nd supervisor, School of Geosciences, University of Aberdeen) and Dr. Jonathan Holland (3rd supervisor, AFBI-NI).
Maarten Blaauw has two decades of research experience with radiocarbon dating and age-modelling, and has produced several statistical tools to produce age-depth models with robust measures of chronological uncertainties. He is Director of the 14CHRONO Centre. Dmitri Mauquoy specialises in carbon sequestration in peatlands as well as the use of peatlands as natural archives of environmental change. Jonathan Holland is a research agronomist with an interest in understanding the effects of soil fertility and other properties on crops. Jonathan is a key researcher on the “Refinement of the regional soil C inventory and evaluation of C sequestration rates on commercial farms in preparation for C trading”, part of CASE partner AFBI’s Soil Nutrient Health Scheme.
The fieldwork will be undertaken in collaboration with AFBI, selecting the most promising and representative sites based on their wide experience of farmlands across Northern Ireland. The student will be mostly based at Queen’s University Belfast, and will have regular contact with Dr. Holland at AFBI and Dr. Mauquoy in Aberdeen.
In the first 2.5 years of the project, the student will undertake fieldwork in connection with the wider AFBI project. The student will also undertake laboratory work from month 6 to month 30. The first year will also be spent producing an extensive literature review on carbon sequestration in farm soils. Months 30 to 42 will be spent analysing the results and writing the thesis. A placement with AFBI is envisaged, the timing and duration of which will depend on the interests of the student, and the development of the research project as well as the wider AFBI soils project.
CASE Partnership with AFBI.