Microbiome Productivity: investigating the photophysiology and productivity of microalgal biomes in coralline algal habitats

Lead Research Organisation: Cardiff University
Department Name: School of Earth and Ocean Sciences


This project utilises the expertise of the UK partners regarding macro and microalgal taxonomy, ecology and physiology, in a novel collaboration with the French partners regarding single cell analysis of samples using the combination of Hyperspectral Imaging and high resolution fluorescence. The subject matter will be the combination of the bioengineer Coralline macroalgae and the epi and endo biotic microalgal biome associated within the fronds of these macroalgae. This is a value added investigation expanding upon a NERC UK Ocean Acidification research Programme studentship project supervised by the UK partners. Coralline macroalgae are calcifying organisms that engineer a 3-dimensional habitat colonised by many endobiotic and epibiotic organisms. A large part of this community is comprised of photosynthetic microalgae. These are important biomes, yet are extremely poorly understood with regard to basic knowledge of community structure, or the functional relevance or interaction of the microalgae and the macroalgae. This project therefore aims to establish a long term collaboration between the UK and French partners, investigating the two photosynthetic components of the biome with regard to community structure, primary productivity and functional photophysiology. Initial pilot data obtained by the PI and the French partners using seagrass (Zostera species) has indicated that paired hyperspectral imaging and high resolution fluorescence imaging produces spectral signatures that can identify the major taxa dominating the epiphytic community growing on the Zostera. Further analysis suggests that this data, paired with high resolution fluorescence may enable analysis of primary productivity, photosynthetic pigments and functional photophysiology (e.g. down regulation, photoacclimation etc.) of individual single cell epiphytes as well as individual segments (intergenicula) of the macroalgal frond. If this proves correct, then the novel pairing of these methods will provide ultra-fine scale data on the photophysiology and productivity of the macroalgae, the microalgae and the interaction between the two. This will greatly expand our understanding of the function of the macro and micro components of these important communities and hence enable a far more informed interpretation of photophysiological data when investigating impacts, such as acidification and light induced stressors, or enhanced carbon dioxide treatments, applied in studies of these important coastal organisms.

Planned Impact

The project will have the following impacts:-
Level 1: Immediate impact - researchers on algal photobiology and coastal ecosystems.
The data obtained from this project will be the first of its kind at the fine scale resolution of individual epiphyte cells and macroalgal intergenicula. This is of key importance in understanding the productivity and photobiology of the microalgae and how this interacts within the epiphytic microalgal biome. Currently work in this field integrates the data obtained without the ability to split the data between the epiphytes, the epiphyte taxa and the host macroalgal frond. In addition the effects of shading and age of the frond are largely ignored with no differentiation of data between the subsections of the macroalgal frond, e.g. across the apical tip to the basal plate and on the upper and underside of each section. Furthermore, this project will achieve high accuracy GIS images pairing the hyperspectral data on pigments and photophysiological parameters, with those of the high resolution fluorescence data on productivity and photoacclimation parameters. Again this is completely novel at the fine scale of the Corallina intergenicula and the epiphyte cell levels. This will provide major advances in the field of knowledge of macro and microalgal photobiology.
Level 2: Researchers investigating environmental impacts of ocean acidification and climate change in general
Data on impacts of stressors such as reduced pH as part of ocean acidification studies etc., have used the integrated data on productivity and other photophysiological parameters. This has been in the absence of data on the inherent variability of these parameters within the macroalgal frond and also within the microalgal epiphyte community as described above. Thus data have been inaccurate as differences between experimental treatments have had differences due to other environmental and biological factors being included within the error of the data measurements, with no knowledge of the level of error of the actual treatment as opposed to that of factors described above. The large scale dataset obtained from this project will address this and enable far more precise determination of true differences within samples to be attributed to experimental factors, once the roles of the epiphytes can be determined and the variability within the macroalgal frond also determined as a factor of position within the frond and sample age.
Level 3: End users interpreting environmental stress impacts on coastal ecosystems
Inherent within the Level 2 impacts will be the ability of non-expert end users to be provided with data on the accuracy of experimental findings from investigations into environmental stressors such as those of climate change and ocean acidification. Thus end users will be better informed on the real effects of such impacts.
Level 4: Education impacts via research led teaching
The findings of the project and the data obtained will be of high use to those teaching on photobiology, macroalgal ecology and other biological aspects.
Level 5: Collaboration between the research partners
The project findings will facilitate further grant applications between the Nantes and UK partners to facilitate further work in this field. This is in addition to the value added nature of the project with respect to the NERC UKOARP project of the UK partners investigating the effects of ocean acidification on calcifying Corallina macroalgae.
Description This work has been the first to accurately measure the host productivity and the epiphyte (organisms growing on the host) productivity in macroalage (seaweed) and microalgae (diatoms and green algae) mixed biogenic reef systems. Their relative productivity and also relative biomass of each group of organisms was determined and hence their role in driving these important ecosystems was determined.
Exploitation Route The work has demonstrated the methodological capability of combining hyperspectral imaging and high resolution fluorescence imaging, with development of analysis tools required for data sets containing many 1000s of data points. This can now be applied to determine the ecosystem function and services of mixed photosynthesis communities such as seagrass, seaweeds, coral reefs etc.
Sectors Education,Environment,Other

Description Public workshop as detailed elsehwere
First Year Of Impact 2015
Sector Education
Impact Types Cultural,Societal

Title Hyperspectral high resolution imaging 
Description We have combined hyperspectral and high resolution fluorescence imaging using GIS referencing to enable ultr-fine scale imaging of cellular productivity and pigment content. This is a completely novel method 
Type Of Material Biological samples 
Provided To Others? No  
Impact None yet, just published in Scientific Reports 
Description Hyperspectral analysis collaboration 
Organisation University of Nantes
Country France 
Sector Academic/University 
PI Contribution There has been increased collaboration between Cardiff University and Universite du Nantes and Universite du Maine (Les Mans) which we are extending through use of the facilities at Nantes as part of a PhD studentship based at Cardiff University (Perkins being one of the three Cardiff supervisors). We hope this will increase the outputs of our collaboration. Recent work on Corallina with a new NERC funded PhD student at Cardiff University is likely to use this collaboration in the next 12 months.
Collaborator Contribution The partners in nantes are offering continued use of their facilities and co supervision of the PhD student described above.
Impact Further planned work on Corallina hyperspectral analysis.
Start Year 2017
Title R scripts for data analysis 
Description The data analysis methods for analysing the large datasets from this study required novel R scripts to be developed. Some of these are available in the current publication (Perkins et al. 2016 Scientific Reports). A further publication to PlosONE is intended on full methodology and with all scripts. 
Type Of Technology Software 
Year Produced 2016 
Impact Improved analysis of large data sets associated with use of fluorescence technology 
Description Public open day as part of Year of Light at National Museum of Wales 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact The aim of the exercise was to increase public knowledge of marine photosynthesis and how light drives marine biodiversity. This was achieved by short workshops and demonstrations using the methods developed during the grant demonstrated on a range of photosynthetic samples. This was an interactive workshop so members of the general public could use the equipment themselves. We used a short feedback form and informal discussions the gauge interest / increase in awareness and feedback was extremely positive. The event was publicised on the museum and university web pages and the Walz facebook site (Walz supplied some of the equipment used).
Year(s) Of Engagement Activity 2015