The development of efficient, affordable solar cells for clean energy production is a major global challenge and in this proposal we are seeking to achieve a breakthrough in the fabrication of novel quantum dot materials capable of substantially improving the performance of III-V solar cells based on GaAs. We propose a close collaborative project with Nelson Mandela Metropolitan University in South Africa, who have complementary expertise in photovoltaic cells, to develop and characterize hitherto unexplored GaSbN/GaNAs type-II quantum dot materials. These strain-compensated, dilute-nitride quantum dots will be implemented within the active region of prototype GaAs based solar cells to significantly extend the spectral response and improve the efficiency. This would lead to a new generation of solar cells for clean electricity generation. Feedback from device studies will provide valuable insight into the photovoltaic properties of these unique nanostructures, further aiding material optimization. The quantum dot materials that we shall develop here could either be used to increase efficiency in single junction cells, or could be incorporated into existing multi-junction cells to replace expensive Ge substrates, reduce cost and significantly increase performance. There are clear opportunities for uptake of the technology both within South Africa and the UK.

Stromatolites are the earliest macroscale lifeforms which are found in the fossil record during the Precambrian and Phanerozoic eras (3.5 billion years ago) and still form today. The characteristic feature of stromatolites is their laminated calcium carbonate structure produced through a close coupling between microbial (Bacteria particularly cyanobacteria, Archaea, and Eukarya, particularly diatoms) activity and geochemical processes, to create a persistent geological structure. Within the last two decades a new type of stromatolite, peritidal (upper shore) stromatolites, was discovered in beach locations in South Africa, Australia and the U.K. EPStromNet will develop a new collaboration of leading international researchers from three continents, that will address key scientific questions underpinning the fundamental nature of these newly identified microbial-geological systems. The assembled team combines senior and early career scientists, complementary expertise, and an excellent track record in delivering leading international science. EPStromNet will pool expertise in microbial and macro-ecology, geochemistry, isotope chemistry and coastal geomorphology, into a new partnership. Cutting-edge next-generation sequencing and eco-informatics tools will be used to identify similarities and differences in the diversity and composition of stromatolite communities within and between continents. These similarities and differences will be aligned with field-based geological mapping and modelling approaches, to determine the associated geological conditions of present and past (during different sea-level states) stromatolites. Stromatolites can be perceived as mini islands, and so allow us to address questions of island biogeography such as the extent to which environmental selection and dispersal limitation influence the diversity and composition of communities living in or on them. This network provides a unique opportunity to explore such macroecological questions at the scale of metres to thousands of kilometres. Furthermore, the depth and taxonomic breadth of our analysis will allow us to ask to what extent these drivers differ between taxa. We will also measure the characteristics of the microbial polysaccharide "glue" that binds the biogeostructures and traps particles, and its association with carbonate structures, key elements in the formation of stromatolites. Metagenomics (analysis on genes in the community)and activity experiments will give a first insight into metabolic processes and how they may lead to CO2 capture and the formation of calcium carbonate structures. This will establish hypotheses that will form the basis of future collaborations. This research therefore comprises a novel world-first investigation into the geobiological dynamics and drivers (genes-to-geosphere) of a range of stromatolite systems, only now feasible because of the discovery of these ecosystems in each of the three locations. No previous direct global-level assessment has been conducted on these stromatolites, nor of any comparable stromatolites in general. Outcomes will include new insights into the processes that create these geobiological systems, address questions of population-level similarity across diverse taxa across global spatial scales, and generate new ideas for interpreting the conditions required for early life and life on other worlds. Peritidal stromatolites are not directly protected anywhere globally, yet as a rare habitat, it is essential to document communities (including novel taxa), learn how they form, and determine their susceptibility to environmental change, so that they can be properly conserved. EPStromNet will create this new research partnership, which will continue into the future through plans to support early career researchers, develop post-graduate student opportunities and identify new research programmes and funding opportunities.

The natural response of the carbon cycle to the warming induced by increased atmospheric CO2 features two negative feedbacks that remove CO2 from the atmosphere. One, caused by the greater acidity of the oceans, is for carbonate minerals to be dissolved, which causes an increase in the ability of seawater to contain carbon (as the bicarbonate ion). The other is for warmer conditions to increase the rate at which silicate minerals dissolve, with the products either precipitated as carbonate minerals, or flowing to the oceans. This silicate weathering also removes CO2 from the atmosphere. Intentional acceleration of these two weathering feedbacks is a potential approach to remove the CO2 added to the atmosphere by burning of fossil fuels, and therefore alleviate extreme climate change. Such an approach is challenging, however, because to be useful at a significant scale (i.e. 1-10 GtC pa removal), requires a dramatic increase in weathering relative to natural rates. Whether such accelerated weathering is a feasible route to remove significant atmospheric CO2 is unknown. This proposal will address this unknown, and provide a comprehensive assessment of the feasibility of CO2 removal by accelerated weathering, including consideration of the technical, economic, environmental, and societal aspects of the approach. The core of our work will be a life-cycle assessment of the enhanced-weathering approaches that might lead to 1-10Gt removal of CO2 per year. This modelling will start from the availability of minerals for weathering, paying particular but not exclusive attention to waste materials from industries such as mining. It will consider how the weathering of these minerals might be enhanced, either through treatment in mining waste piles or, in collaboration with project partners, by addition to soils. It will also consider the fate of the weathered materials, either as carbonate on land or in the sea, or as alkalinity in the sea. It will assess the economic cost of such approaches, the energy requirements, the environmental damage they would cause, and the societal limitations on such approaches (e.g. social acceptability, political, legal, governance). In some key areas, understanding is not yet sufficient to allow this life-cycle assessment. We will address these gaps in knowledge by five specific pieces of research. These will: 1. Characterise how much waste material is available for enhanced weathering, including its location, its grain size, and its chemistry and mineralogy. This is critical information to underpin the life-cycle assessment. 2. Measure how quickly typical minerals weather and how this weathering rate changes with temperature and, particularly, through addition of microbes that are known to cause accelerated weathering of silicates. 3. Assess how best to scale up weathering to the 1-10GtC pa level. This will be done by both modelling of possible engineered approached to weathering, and by experiments on piles of silicate and carbonate minerals (each of 10 cubic meters), in which the conditions are altered and responses measured. 4. Assess the response of the ocean to increased alkalinity resulting from enhanced weathering. If more carbonate is produced in the ocean, it reduces the effectiveness of enhanced weathering; we will measure the rates of both inorganic and biological carbonate formation and their impact in the C cycle globally. 5. Consider how society will response to possible scenarios for accelerated weathering, and whether this may limit such an approach. Will enhanced weathering be socially acceptable? Will there be the political will to pursue it? Are their legal or governance barriers? Information from these five "research components" will provide critical information for the life-cycle assessment, and thereby allow the overall potential and challenge of enhanced weathering CO2 removal to be fully assessed.

Microplastics (MPs) have been found in virtually all environments: soil, living things, water and air. The past five years have included a small number of investigations over long time scales (up to a year for some) and across wide ranging locations. One common finding is that MP numbers and types vary greatly in different environments. There is now concern regarding the possible impacts of MPs in terms of public and other organism health. MPs are of the size range range of 1 micron to 5 mm, which ranges from the size of a small bacterium to a sesame seed at most, inhalable, and common in food chains/diet. They come in different shapes and polymer types, depending on the plastics that are derived from eg. polyester or polypropylene, which are common in textiles or packaging. Recently, they have been identified inside people's lungs, blood and bowels, and questions arise as to whether they cause or exacerbate lung or bowel conditions like chronic cough or irritable bowel disease. In marine organisms they are also associated with growth and inflammation type impacts. Current air quality measures and monitoring completely overlook this contaminant type, which is likely to become a public health issue. Current measurements of the types of particles and gases in routine air monitoring also fail to completely explain high levels of specific cough and inflammation type disease incidences in many cities. This study firstly aims to establish a means to measure MPs in the air, which would represent a new air quality measure methodology. The approach we suggest 'slip streams' the current pollen monitoring methods available worldwide, making it accessible for those who do not have access to specialist and expensive equipment. The method proposed does however have certain robust elements included and these are to ensure that the agencies who conduct air quality measurements can use the data produced. The second aspect of this work is to develop an automated identification and counting technology approach so that the monitoring can be completed in future using low cost, non-specialist equipment and expertise. Ideally, the method will be available for reliable and reproducible use around the world. This will be achieved by a combination of manipulation of existing available datasets on MPs found in the air (from our past three years of studies), and trials with colleagues located across four continents who work with different pollen sampling approaches. One novel approach we will use will be to make a set of MP 'reference strips' that can be posted to users and used an as internal calibration when taking images for analysis. There are parallels between established pollen monitoring and trying to set up something similar for MPs, that we can exploit. Pollen come in a comparable range of shapes and sizes (ranging from 5-100+ microns) to MPs. They are a trigger for health impacts and, as such, are routinely and robustly monitored such that datasets can be shared and compared internationally as well as communicated to the public. The same parameters can apply for MPs. The second aspect, the auto-identification and counting would represent a significant step forward for both pollen and MP monitoring, that could see wider benefits still. The trials we conduct will run in parallel with the current practice for MP sampling, to add further cross comparison but also to anchor any new approach to what is currently deemed as acceptable in the wider community of research scientists working in this area.

Ten percent of the world's population depend on the ocean for a readily accessible source of protein and employment, with the majority (95%) living in developing countries. Poor coastal communities are at the frontier for climate change impacts, compounded by population growth and food demand, but are among the least resilient to the challenges of the future. SOLSTICE-WIO will focus on coastal communities in nine developing countries and island states in eastern Africa, interlinked culturally and ecologically and collectively known as the Western Indian Ocean (WIO) region. All nine (South Africa, Mauritius, Seychelles, Kenya, Tanzania, Mozambique, Somalia, Madagascar, Comoros) are on the list of Official Development Aid recipients, with five identified as Least Developed Countries. In the WIO over 100 million people live within 100 km of the ocean, with a significant proportion employed in local fisheries. This leaves the region highly dependent on the ocean for economic stability, food security, and social cohesion. These coastal communities have limited adaptive capacity to cope with dramatic reductions in fish stocks caused by overfishing, habitat destruction, and increasing environmental pressures - all aggravated by climate change. The decline of WIO fisheries has had profound socio-political ramifications, from the rise of piracy to general political instability. A clear example of the devastating effect of a fish stock reduction is the collapse of the Chokka Squid fishery in South Africa. SOLSTICE-WIO will use this as a case study to demonstrate the strengths of a holistic approach to human-ecosystem-fisheries research and the potential solutions this can offer. The squid fishery was the 4th most valuable fishery in South Africa, bringing foreign currency into one of the poorest provinces. It was directly employing 5000 fishermen with 30,000 dependents. The 2013 crash had a devastating effect on the Eastern Cape, yet the underlying reasons are unknown: local fishermen believe the collapse was caused by environmental change. Until the mechanisms behind the collapse are understood, there is little potential for aiding recovery or guiding adaptation. SOLSTICE-WIO will provide this urgently needed understanding to help inform the fishery and Government as to the fate of the local ecosystem, whether it will recover, and whether the crash could have been predicted or prevented. How will SOLSTICE achieve this? The key to stability of living marine resources lies in an ecosystem approach to fisheries (EAF), which sees human-natural systems as a whole, integrated entity rather than separately considering individual target species. Simply put: you cannot manage something you don't understand, nor can you adapt to change through management improvements unless you can describe, measure and understand the changes. The core strength of SOLSTICE-WIO lies in its integral approach to food security, drawing on UK expertise in physical oceanography, marine ecology, autonomous observations, environmental economics and the human dimension,and WIO expertise in fisheries, the marine economy and regional policy development. SOLSTICE will provide the region with the state-of-the-art technology to deliver cost-effective marine research and provide the information needed to achieve maximum potential from the region's living marine resources. In the UK marine robotics, ocean models and novel data products from satellite observations have developed rapidly in the last decade, and now underpin Blue Economies and Ocean Governance in Europe. These technologies are highly agile and ready to be applied in the developing world as cost-effective ways to maximise understanding and sustainable exploitation of living marine resources. Such "technology leapfrogging" can overcome the severe lack of research ships in the WIO and save decades of effort in developing predictive modelling systems from scratch.