The oceans support a large proportion of global biodiversity. Sustaining life at the base of marine food chains are photosynthetic microbes, known collectively as phytoplankton. These organisms are vital in regulating our climate, absorbing carbon dioxide from the atmosphere. They also generate almost half the oxygen we breathe. Phytoplankton are probably best known for their formation of massive 'algal blooms' in the ocean, due to rapid population growth triggered by a combination of physical and biological factors. Due to the release of harmful toxins, some phytoplankton blooms can have a negative impact on marine ecosystems, fisheries and human health. Effects of climate change and nutrient pollution have led to more severe and frequent blooms. However, many blooms are not caused by harmful species, and are vital for sustaining marine ecosystems including fish populations. To better understand factors that control bloom dynamics and toxicity, we need to learn more about the molecular processes that trigger their sudden proliferation, and subsequent demise. In many parts of the ocean, nutrients such as nitrogen and phosphorus are in scarce supply. This can limit phytoplankton growth, and cause competition between microbes for survival. In the marine environment a combination of physical factors can lead to sporadic increases in nutrients. This is one of the factors that can stimulate rapid proliferation of phytoplankton cells and lead to algal bloom formation. One of the most successful phytoplankton groups in modern oceans is the diatoms. Diatoms are particularly good at detecting favourable conditions and are often the first to dominate the early stages of bloom formation. Moreover, their success in regions of pulsed nutrient supply suggests that they possess sophisticated mechanisms for sensing and responding to fluctuations in nutrients. However, the sensory mechanisms that mediate the cellular responses of diatom cells to key environmental stimuli remain poorly understood. This represents a major knowledge gap, especially since it is the signalling mechanisms that coordinate acclimation to the environment that likely underpin the ecological success and global impact of the diatoms. I have generated a cutting-edge toolkit to study how diatoms are able to sense changes in their environment using the signalling molecule calcium, which functions as a messenger within the cell. This has led to the remarkable discovery that diatoms use calcium for detecting pulses of the nutrient phosphorus. This novel nutrient signalling mechanism is distinct from plants and animals and points to fundamental differences in nutrient perception between these organisms, which need to be elucidated. I will dissect specific components of this signalling pathway to identify how it helps diatoms respond rapidly to changing nutrient conditions and contribute towards bloom formation. Using my innovative tools, I will also examine other unknown aspects of the diatom sensory system. Alongside physical factors, biological interactions of diatoms with other microbes such as competitors, parasites and predators can critically regulate their growth and bloom development. In the second part of my proposal I will examine how diatoms are able to sense, and alter their behaviour to interact with, their microbial neighbours. Since both nutrient supply and bacteria can govern toxin production by harmful diatoms, a key objective will be to expand my molecular tool kit to the toxic bloom-forming diatom Pseudo-nitzschia multiseries. This research will identify mechanisms that govern dynamics of a globally important phytoplankton group that supports some of our major marine resources. The work will moreover provide insight of regulatory processes and 'master-regulators' that coordinate cellular responses to key environmental drivers that impact diatom growth and toxicity of harmful diatom species, allowing us to better predict bloom formation and toxicity.

The global oceans currently absorb ~30% of anthropogenic CO2 emissions. The carbon cycle that regulates this ocean-atmosphere CO2 exchange, and the associated vertical distribution of dissolved carbon and alkalinity that influences the ocean's absorption capacity, depends on several processes. These are described as a series of interacting "pumps": a physical/chemical solubility pump; a biological 'soft tissue' pump; and a calcium carbonate pump. Understanding these three pumps, how they interact, and their atmospheric CO2 feedbacks is especially critical for accurate predictions of how the marine carbon cycle and global climate will change in the future. Calcium carbonate is a white, chalky mineral produced by a range of marine organisms. Importantly, when it dissolves it increases the alkalinity of seawater, which can reduce the seawater CO2 concentration below atmospheric CO2 levels and 'suck' anthropogenic CO2 from the atmosphere. Knowing exactly where it dissolves (how near the ocean surface) is therefore key to understanding the role this calcium carbonate pump plays in regulating ocean chemistry and atmospheric CO2. The operation of the calcium carbonate pump not only depends on the production rate but also the types of carbonate minerals that are produced by marine organisms, the rate at which they sink, and how rapidly these carbonate minerals then dissolve. Most ocean carbon cycle models make the assumption that carbonate production is dominated by the plankton and coccolithophores (microscopic algae). However, we now know that very large amounts of carbonate are excreted by marine bony fish (teleosts). This carbonate, which we now also know is mineralogically diverse depending on the fish species, is continuously produced in the intestines of fish and excreted as waste. The potential significance of this process to the marine CaCO3 pump was recognised in an initial modelling exercise led by PI Wilson (Science, 2009) which conservatively suggested that fish may account for at least 3-15% of total marine CaCO3 production globally, and realistically as much as 45%. Since that first modelling exercise the science behind this process has advanced hugely. As a group (and through the work of others) we now know that fish produce a hugely diverse range of carbonate mineral types, which existing knowledge would suggest should dissolve at very different rates. As a result, the assumptions in the first modelling efforts that fish produce uniform and relatively soluble carbonate types are no longer valid. Whilst we can already address some of the knowledge gaps, there is little or no data for fish from families that comprise ~94% of global fish biomass - including almost no data for mesopelagic fish that alone account for at least 60% of fish biomass. The daily vertical migration of their immense biomass is hypothesised to drive a novel "upward alkalinity pump", which may provide an important offset to the downward transport of alkalinity driven by other established processes. Also, we now have good evidence to show that production rates by fish vary with metabolic rate (which is greatest in the globally significant active epipelagic fishes), and importantly also depending upon feeding and diet (especially the calcium content of the diet). Thus, again, necessary assumptions in early models that all fish produce carbonate at the same rate are no longer realistic to use for modelling. Over and above these issues we also have little to no data on the rates at which these carbonates sink in the oceans or dissolve. The aim of this project is therefore to deliver new empirical data on fish carbonate production, mineralogies, solubilities and sinking rates to inform the first spatially- and mineralogically-resolved global production estimates, thus enabling us to parameterise models assessing fish contributions to the marine carbon cycle both under present day conditions, and for climate change scenarios in the future.

The UK is currently at the forefront of the Marine Renewable Energy (MRE) sector, with almost 200 MW of installed capacity of wave and tidal stream projects, that are either operational, under construction or in development. Furthermore, the first floating offshore wind farm is being built off the coast of Scotland. In order to realise the potential of MRE to achieve the targets set by the Government and keep the UK's leading position; the sector needs to address some relevant technical, environmental and interdisciplinary challenges. A coordinated response from different actors at national and regional level is required in order to successfully face these challenges. In an attempt to provide this coordination and with an initial focus on the South west of the UK, the Partnership for Research In Marine Renewable Energy (PRIMaRE) was established, bringing together research expertise and access to facilities for MRE developments. PRIMaRE comprises the Universities of Plymouth, Exeter, Southampton, Bristol and Bath, along with the Marine Biological Association and Plymouth Marine Laboratory. Completing the line-up of PRIMaRE is the South West Marine Energy Park and the Wave Hub facilities, acting as conduits between the research community and industry. More recently, PRIMaRE has extended its borders both nationally and internationally by including the Universities of Uppsala, Cardiff and Cranfield as associated partners of PRIMaRE. The core partner institutions have signed up to a partnership agreement to work together on research across the spectrum of MRE and to establish a 'network of excellence' centred in the South of the UK. PRIMaRE has established the annual conference (now in its third year) to showcase the research and provide a forum for discussion with MRE industry and academia, and have organised industry oriented workshops to identify research priorities in order to align research efforts with the requirements of the MRE sector. With the support of the EPSRC Network Grant, PRIMaRE aims to expand the partnership to a new level, making active and effective contributions to the challenges of the MRE sector. The Network brings together academic effort on MRE challenges, but also given the nascent state of the industry, aims to work closely with supply chain and industry partners, by providing training and a forum for sharing and exchange of ideas and through access to academic expertise and facilities. Unlike the academic focus of doctoral training schemes, the proposed network aspires to a broad sector approach, in which training and research collaborations are promoted both for conventional research and academic staff (i.e., post-docs, researchers, academics, PhD students) and for industry staff (developers, supply chain, test centres, regional government agencies). The proposed network has four main pillars of focus: (i) the annual PRIMaRE conference, expanded to become a key National and International event for the sector; (ii) the Key Challenge Workshops, an industry oriented dynamic and proactive forum to ensure alignment of PRIMaRE research priorities, and to focus on key emerging challenges requiring special attention; (iii) travel grants, which are crucial to ensure knowledge transfer and to promote the required mobility between academia and industry needed to develop new research collaborations nationally and internationally; and (iv) the PRIMaRE summer school, a continuing professional development (CPD) high level programme, providing the mechanism for exchange of knowledge between the research, academia, the novel MRE industry and wider sector.

Ecosystems are communities of organisms that interact with each other and their environment. They are often considered in terms of food webs or chains, which describe the interactions between different organisms and their relative hierarchies, known as trophic position. Ocean ecosystems provide key services, such as nutrition, control of climate, support of nutrient cycling and have cultural significance for certain communities. It is thus important that we understand how changes to the environment reshape ecosystems in order to manage climate change impacts. The Arctic Ocean is already being heavily impacted by climate change. It is warming faster than any other ocean region and as it absorbs fossil fuel emissions, it is gradually acidifying. Arctic sea ice is declining by 10% per decade. This affects the availability of sea ice habitats for organisms from plankton to mammals and modifies the ocean environment. Finally, the Arctic is affected by changes in the magnitude of water movement to and from the Pacific and Atlantic Oceans and composition of these waters. Thus Arctic ecosystems are being impacted by multiple concurrent stressors and must adapt. To understand how Arctic ecosystems will evolve in response to multiple stressors, it is crucial to evaluate the effects of on going change. Often these questions are tackled by studies that focus on a specific ecosystem in one location and document the various components of the food chain. However the Arctic is diverse, with a wide range of environments that are responding to unique stressors differently. We require a new approach that can provide information on Arctic ecosystems from a pan-Arctic perspective over decadal timescales. To effectively monitor changes to pan-Arctic ecosystems requires tracers that focus on key ecosystem components and provide quantitative information on ecosystem structure, providing information for management and conservation of ecosystem services. Our goal is to respond to this challenge. We will focus simultaneously on the base of the food chain, controlled by the activity of marine phytoplankton, and key Arctic predators, harp and ringed seals. Seals are excellent candidates to monitor the food web due to their pan-Arctic distribution and foraging behaviour, which means they are exposed to the changing environment. Nitrogen and carbon stable isotopes are often used to examine ecosystems as they are modified during trophic transfer up the food chain. Hence, they can quantify seal trophic position and food chain length, key determinants of ecosystem structure. Crucial in this context however is the isotope value of the base of the food web, known as the isoscape, which is itself affected by a range of environmental characteristics and fluctuates in space and time. Equally, by virtue of changing migration patterns, seals themselves may feed on similar prey in different isoscapes, which would affect the interpretation of ecosystem structure from stable isotopes. These are the major challenges in using stable isotopes. We will link stable isotopes to novel tracers of the food web, known as biomarkers. When these tracers are compared against observations of the shifting isoscape and data on seal foraging, they permit seals to be used to monitor the Arctic ecosystem by quantifying their trophic position and overall food chain length. Via a range of observational platforms, our new food web tracers will be mechanistically linked to the spatial and seasonal trends in the Arctic isoscape and seal behaviour. By then combining historical observations from around the Arctic basin with state of the art ocean and seal population modelling, we can quantify past and future changes in Arctic ecosystems. This will provide information on past changes to Arctic ecosystems, but also put in place an approach that can be used to monitor future changes and aid in the management and conservation of ecosystem services

Much of what we know about how cells function, how they communicate and process information and how they transport essential elements and molecules has come from the application of electrophysiological approaches. The most well known example of this is the pioneering work of Hodgkin and Huxley, carried out at the Marine Biological Association (MBA) with the giant nerve fibre of the squid which led to the discovery of how nerve cells transmit impulses and formed the basis of much modern neurobiology. Since these seminal discoveries the field of electrophysiology has expanded dramatically and electrophysiological approaches are applied to study a wide range of processes in cells, including the functional characterization of molecules that are increasingly being characterised at the molecular level. In 1984 it was decided that there was a need for an annual research workshop to provide training in the varied uses of microelectrode techniques. This has proven to be a very valuable contribution to cell biology and biophysics and has had significant impact on the training of new generations of cell physiologists. The MBA was chosen as the venue for this workshop since it provided both excellent workshop facilities and a continuing tradition of microelectrode and associated biophysical approaches in cell biology. The workshop has continued uninterrupted since then and is now recognised worldwide as one of the leading advanced research workshops in this field. The need to train the new generation of electrophysiolgists continues, particularly with the increased emphasis on functional characterisation of membrane proteins and a wide range of cell biological areas. The workshop continues to be over-subscribed with applications 3-4 fold each year for the 20 places available. To meet this continuing need the proposed 5-year extension to the ongoing workshop will provide training in both the basic principles and more advanced practical and theoretical aspects of electrophysiology. New approaches are planned to be incorporated over this period. The basic workshop fomat will continue with a core of teaching and demonstrating staff recruited mainly from research laboratories in the UK and Europe along with an intensive series of talks and demonstrations from invited international experts. The workshop also benefits from the good relations that have been established over 28 years with a large number of commercial instrument manufacturers that ensures significant in-kind contributions of equipment and who also contribute expertise as instructors.