Currently a Honorary Associate of the Ecological Sciences programme at the James Hutton Institute and an honorary lecturer at Dundee University teaching Microbial Ecology, I have held postdoctoral positions at York, Lancaster and Durham Universities after completing a PhD at Warwick University and degree at Nottingham University.
Current research interests
Arbuscularmycorrhizal ecology
For many years I have been involved in mycorrhizal ecology focussing on the dynamics of arbuscularmycorrhizal (AM) fungi. I have been heavily involved in the development of the application of molecular methods to improve understanding of community dynamics of this key fungal group resulting in the publication of a number of high impact papers. Work has focussed on the impact of arable farming on AM fungi with published work highlighting the depauperate nature of the group under conventional farming. Additionally work in grasslands discovered both host preference and links to bacterial communities and recent work in a boreal system, through collaboration with the University of Tartu including MaarjaÖpik[2], uncovered an unexpected high richness in AM fungi, linked community structure to functional differences and identified a link between community structure and plant functional group. Current projects include: work primarily by Jane Davidson further exploring community dynamics in arable systems, a PhD student, Alex van den Bos[3], co supervised by Alison Bennett[4] and Dave Johnson[5] (University of Aberdeen) exploring the effect of tillage on AM fungi community structure and function and work with Alison Bennett and Sandra Caul exploring the role of plant breeding in reducing crop response to AM fungi.
Microbial nitrogen cycling
Since appointment at the Institute I have been involved in the area of microbial nitrogen cycling in soil. This work area has recently been expanded mainly through an active collaboration with Liz Baggs[6] at Aberdeen). This collaboration has taken the form of joint studentships funded either through NERC CASE or the Institute/University joint scheme. Miriam Herold undertook a project examining the relative role of fungal and bacterial denitrification in arable systems mainly utilising a long term pH gradient at SAC Craibstone. MaddyGiles is exploring the role of rhizodeposition in driving denitrification using artificial root systems. MarcinSkiba, who is also jointly supervised by Tim George[7], is undertaking a project examining the mechanisms lying behind variation in biological nitrification inhibition (BNI) observed between barley cultivars. Other work in this area, undertaken primarily by Susan Mitchell, is exploring the differences in nitrous oxide emission observed between different barley lines that may provide breeding targets to aid reduced arable farming environmental impacts.
Free-living nematode dynamics
Nematodes provide an opportunity to understand the soil food web since they are a keystone group with representation at most trophic levels within the soil food web. For this reason free living nematodes have often been suggested as an ideal group for the estimation of soil health although issues associated with sample processing due to time consuming traditional identification have often limited application. A student at the Institute, Suzanne Donn, funded by the BBSRC and supervised jointly with Roy Neilson[8] and Bryan Griffiths[9] (currently at SAC Edinburgh) developed and tested a molecular method based on terminal restriction length polymorphism (T-RFLP). This method allows a massive increase in the numbers of samples that can be analysed which will allow the application of nematode community dynamics to be considered as an indicator of soil health for monitoring purposes. The methodology has been tested in other systems as part of joint student projects undertaken by Xiaoyun Chen, in Ireland also supervised by Bryan Griffiths, Roy Neilson and Vincent O’Flaherty (UNIGalway), and StefanieVink on the Machair of the Western Isles (supervised jointly with Roy Neilson and David Robinson[10], University of Aberdeen). Recently we have undertaken a project, employing Lea Wiesel[11], exploring spatial structure in a sand dune system to further test and develop the methodology.
EnPrint
The intransigent nature of soil ecology driven largely by the lack of culturability and high diversity of the associated microbial community has driven a reliance on molecular methodology. These tools have been developed to be robust in relation to co-extracted inhibitors and provide the high throughput of samples required to allow the testing of ecological hypotheses. These tools have other applications that are being exploited through the spin out companyEnPrint[12]. Recent developments include a project co-funded by the Technology Strategy Board and Scottish Water to quantify and identify Cryptosporidium species in regulatory water samples.