Molecular metrics for assessing the status of peatlands

Peatlands, thick water-logged organic matter rich soils produced by the decay of plant and animal materials, are vital to humanity by providing countless benefits and ecological services. They represent a major carbon store, containing twice the amount of carbon than the entire forest biomass on this planet. When in a healthy condition, peatlands continuously remove carbon from atmosphere, helping our battle against climate change.
Peatlands are natural sponges, holding up to 90% water and their ability to retain this water is important not only for sustaining their stability but also for providing a source of drinking water (e.g. 70% of UK drinking water runs from upland peatland catchments). They are also an important factor in flood management. Peatlands provide a unique habitat for many plant and animal species. Globally, peatlands have been damaged by human activities such as drainage to promote grazing lands, or extraction for a fuel or for making whisky; around 80% of UK's peatlands are classified as damaged. Damaged peatlands are a major cause for concern as they cannot provide many of their vital ecosystem services, e.g. they start releasing carbon rather than storing it.
Rewetting of peatlands, thus raising their water table, is a widespread method for peat bog restoration. This reintroduces conditions where species like Sphagnum moss return, reducing the loss of carbon to waters and the atmosphere. However, recent studies suggest that rewetting does not always restore the peat back to full health in terms of biodiversity, water dynamics and carbon sequestration capacity. In order to understand these issues we need to ask a question: what is the peat made off? If peat is losing carbon, what are the molecules that are most affected? What if degradation removed some of the key molecules that protect peat against decomposition and carbon loss? What then happens when we try to restore the peat? In such instances, peat may not be able to return to its healthy state and rewetting could even cause it to degrade further. A better understanding of these processes at the molecular scale is required in order to suggest site specific measures that could address these issues. By developing molecular metrics to classify and monitor the restoration levels of peat we will help in preventing further peatland damage.
The aim of my project is to examine changes of peatlands on the molecular level by comparing molecular characteristics of intact, degraded and restored sites. As human health has been advanced through structural studies of biomolecules yielding molecular level understanding of their function, molecular level structure-function relationships need to be developed for soil systems. The progress in this area is hindered by incredible complexity of soil organic matter, which is commonly cited as the most complex mixture on this planet. NMR and MS are universally acknowledged as the two most promising techniques for characterisation of the molecular composition of organic matter and I will use and further develop these techniques in my research.
In my previous work I have already demonstrated the power of NMR to unravel the structures of certain, important types of molecules found in peat. The aim of the proposed work is to provide comprehensive, molecular level characterisation of peat. I aim to uncover the differences in molecular composition of peat organic matter and organic matter from peat pores in different bog conditions and to provide a molecular metrics to characterise the status of peat bogs. Such research is required to monitor effectiveness of restoration/preservation schemes and ultimately will contribute to bringing the bogs back to health and keeping them there. Once we know the molecules, we know what is happening to the carbon pool; we can follow its movements in and out of peat bogs, and therefore also improve models predicting effects of future land use and climate change on peat.

Academic Impact
My research will develop molecular scale metrics to assess peatland status by combining information from liquid- and solid-state NMR and mass spectrometry (MS). Adding molecular information will not only add value to existing monitoring schemes based on bulk measurements, but will open new avenues to add reasoning to the observations made, by unravelling the cause and effect relationship for the observed changes. Particular beneficiaries will be those in the field peat soil science. For example those monitoring the status of peatlands by examining microbiota as links could be made between the chemical composition and microbial activity.
Peatland carbon cycling is not fully understood and thus molecular information, especially when combined with other carbon turnover measurements, will improve the quality of carbon cycling models.
The wider soil science community will also benefit from the developed methodology and data collected in this work. Soil organic matter (SOM) has a role in biogeochemical cycles of all soil types and in each case the exact structure-function relationships are not fully understood. Knowledge of the molecular composition is essential for full understanding of processes occurring within soils. For example, the removal of pollutants in soil and aquatic systems will become most effective when we understand their interactions with environmental matrices on a molecular level.
Individual tools (tagging chemistry, NMR and MS protocols) answer the request for high-resolution analytical techniques for structure characterisation of complex mixtures such as biofluids, pharmaceuticals, plant extracts, lignin degradation products as well as food and beverages. Current methods for mixture analysis rely on MS (particularly GC-MS) or 1D NMR screening or FT-IR which can only be utilised effectively if the compounds present in mixtures are already known, whereas the untargeted approach offered e.g. by the tagging methodology does not have this limitation.

Economic and Societal Impact

Peatlands provide vital ecosystem services. They regulate catchment hydrology, mitigate climate change and offer a habitat for diverse biota. They are a symbol of national identity, a record of cultural and environmental history and an icon of outdoor recreation. Reflecting their importance, a number of governmental organisations, charities, professional groupings, and industries have stakes in maintaining healthy and fully functioning peatlands.
Effective monitoring of managed peatlands and restoration actions will ultimately translate into reduced the costs to industries and governments that occur due to peatland damage, such as floods, landscape erosion, GHG emissions, habitat degradation, water quality issues and health issue. Creating a reliable metric will also guarantee that the public spending and industrial investment in peatland restoration are properly accounted for.
Chemical and physical properties underlie efficient design and optimisation of membrane technologies, water treatment plants and DOM removal. Characterisation of DOM at molecular level thus will contribute to the sustainable provision of safe drinking water to all communities.
Engagement with the public, explaining the analytical techniques in the context of the ecosystem services of peat will bring personal and societal benefits in inspiring and educating future generations to safeguard these lands.
As a by-product of my research, the development of methodology for compositional analysis of complex mixtures will have an impact on numerous industries, who will be able to use the developed methodology to characterise complex mixtures in order to comply with 2006 EU regulation (REACH). Industries analysing complex mixtures in areas of soil fertility products, nutraceuticals or beverages will particularly benefit.