Phenology of grass flowering at the species level

Bioaerosols are a heterogeneous group of particles such as pollen, fungal spores, bacteria, viruses and fragments of plant or animal material. An important subsection of the bioaerosol are aeroallergens that negatively affect human health. In Europe and the UK, the single most important outdoor aeroallergen is grass pollen (Sofiev et al, 2013). Nevertheless, currently no atmospheric model has been used successfully for describing/predicting atmospheric concentrations of different species of grass pollen. This is partly because detailed, spatially relevant maps reflecting both presence and abundance of vegetation and pollen at the species level do not exist and partly because the most common atmospheric models used in pollen dispersion studies are not well suited for the atmospheric scales that are implicated in grass pollen dispersion (Skjøth et al, 2013). These components are currently under development in the two projects “A Simple Unified Pollen and Spore Emission Model – SUPREME” and “Using molecular genetics to understand grass species pollen deposition: enhancing bio-aerosol models and implications for human health” funded by the European Commission and the National Environmental Research Council (NERC) and coordinated by Dr. Skjøth and Dr. Creer, respectively. An important component in these projects is the mechanistic description of the flowering of individual grass species. However, they do not address the causes of local scale variations in grass pollen exposure, which has shown to be a decisive parameter in some areas (Skjøth et al, 2013b). Microscale variability will be further explored in this PhD project by observing how individual grass species flower, exploring the hypothesis that flowering vary dramatically between species (Peel et al, 2014) and explaining how this can affect the atmospheric composition of grass species at a local scale. As such this project addresses one of the main scientific challenges in aerobiology: local scale variations of pollen and the escape fraction of pollen that enter into regional scale transport (Sofiev et al, 2013).

This PhD project will therefore support a predictive framework for the assessment of the spatio-temporal deposition of grass species pollen and identify which species or combinations of species are linked to the most severe public health outcomes of the allergic response (i.e. asthma).

Ultimately, the aim is to develop a mechanistic description of the hourly flowering process of specific grass species for implementation into atmospheric transport models that can be used for both scenarios, exposure studies and next generation pollen forecasting. The primary objectives of the project are to:
1. Investigate the flowering process of selected individual grass species found naturally in the UK
2. Investigate how the flowering process of individual grass species relates to environmental variables such as temperature, humidity, rain and wind and describing a relevant mathematical relationship for grass flowering.
3. Investigate vertical concentrations of grass pollen at the species level using both traditional samplers and drone technology.
4. Explain observed variations of grass pollen concentrations using existing mathematical models such as HYSPLIT and a new mathematical description for grass flowering developed by the student
5. Develop a local scale grass emission map by combining 1-4 with existing high resolution satellite pictures from the Worldview-2 satellite thereby testing the hypothesis that urban concentrations of grass pollen is related local sources.

The student will be expected to carry out their individual research study under the direction of Dr Carsten Skjøth (Director of Studies, University of Worcester), Beverley Adams Groom (University of Worcester) and Dr Simon Creer (Bangor University).

Applicants should have a First or Upper Second (2.1) Honours Degree. Education to Masters Degree level in a relevant subject area would be advantageous. Excellent oral and written English are a must, as are a commitment and enthusiastic approach to completing a higher research degree.


For the full advertisement and for an application form visit: http://www.worcester.ac.uk/researchstudentships

For an informal discussion about the studentship please contact Dr Carsten Skjøth (email: [Email Address Removed])

For questions regarding the application process, please contact Katherine Bruce (email: [Email Address Removed] or tel: +44 1905 54 2182)

The closing date for applications is Tuesday 22nd November 2016. Successful candidates will be invited for interview in December 2016 (date TBC).