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Delta dynamics: a numerical investigation of the inhibiting effects of tidal range and significant wave height on delta development
Get PDFIn this thesis, the process-based numerical model Delft3D 4 (Deltares, 2021a,b) is used to investigate how tidal range and significant wave height affect, and potentially prevent, the development of river deltas within a range of idealised simulations. In order to reduce the parameter space and hence simplify analysis, focus is restricted to just the effects of wave height and tidal range, following the assumption that the effects of discharge are relatively linear and predictable—i.e. lower river sediment flux equates to reduced likelihood of delta formation. The primary objective of the work, therefore, is to determine if there exist limits of significant wave height and / or tidal range beyond which delta formation is prevented, and to elucidate the relevant processes where (if) this is found to be the case.
To this end, we investigate how delta development is affected under increasing values of wave height and tidal range, both independently and in combination, leading to the identification of four distinct regimes of delta formation. We then discuss the mechanisms by which delta formation is prevented in our simulations with the largest tidal ranges and wave heights, hence also identifying a fifth regime of delta-suppression. Each of these five regimes is qualitatively compared to representative real world examples of (non-)deltas, and the work is positioned against existing literature regarding the limits of delta formation and classification of deltas by process-dominance.
Finally, based upon the observation that waves and tides in combination act to functionally ‘diffuse’ sediments away from the mouths of rivers in the simulations, it is hypothesised that deltas do not form when such diffusion is of sufficient magnitude to prevent the formation of persistent deposits (and hence deltas) within the vicinity of river mouths. This hypothesis is tested via comparison to a 1D along-shore sediment diffusion formula with a source term representing river sediment discharge. This formula is found to match sediment distributions of the process-based simulations with increasing accuracy under the larger significant wave heights and tidal ranges modelled
Hydrothermal carbonisation of cotton and polyester clothing waste for hydrochar and terephthalic acid production
No full textIn the UK around 93,000 tonnes of clothing waste, which typically contain 55 % cotton and 23 % polyester, are sent to landfill every year. Under the European Green Deal, polyester terephthalate (PET) manufacturers are under pressure to increase recycling rates to 30 % by 2030. Therefore, this study focusses on using hydrothermal carbonisation (HTC) to produce terephthalic acid from both coloured PET and clothing waste containing dyes. The purity of terephthalic acid is important for recycling and typically needs to be over 99 % without measurable colour for manufacturing recycled plastic. Therefore, the specific aim for this study is to purify terephthalic acid from coloured PET bottles and polyester-containing clothing waste and, for the latter, to produce a hydrochar co-product that can be used as a solid hydrochar.
Prior to studying HTC of cloth containing cotton and polyester, it is important to understand the behaviours of pure cotton cloth. There are several previous studies on the HTC of cellulose, but none on cotton cloth. It was established that the main difference between cellulose and cotton cloth in HTC is the temperature at which aromatic carbon is produced in the hydrochar. These are 200 °C and 240 °C for cellulose and cotton cloth respectively. This is because of the flame-retardant chemicals added during the cotton cloth manufacturing process. The impact of post-HTC aqueous liquor as the partial feedstock was also investigated and it was found that this was beneficial for increasing the hydrochar yield for cotton cloth, implying that the water-soluble organics contribute to hydrochar formation through combination reactions. However, the increase in hydrochar yield was accompanied by a decrease in calorific value due to the oxygen content increasing.
Although the hydrolysis of PET has been widely investigated, there are no previous reports on how dye can be removed effectively to produce colourless high purity terephthalic acid from coloured PET bottles. The study of hydrolysis of polyester cloth showed that unreacted polyester increased with the Run of recycling aqueous liquor, due to the reactant (water) reduction. The yield of recovered terephthalic acid also increased with recycling the aqueous liquor, due to less dissolving which could be related to the water-soluble organics and ethylene glycol presence. For the coloured PET bottles, hydrolysis took place with pure deionized water. After that, the filtered solid product was mixed with sodium hydroxide solution to produce disodium terephthalate solution. The activated carbon adsorption was successfully applied to treat the disodium terephthalate solution. The removal of dyes produced a whiter and brighter sample of terephthalic acid compared to a commercial standard sample and reached over 99 % purity.
For the hydrothermal carbonisation of mixed cloth, the hydrochar yield increased on recycling the aqueous liquor containing any unprecipitated terephthalic acid and ethylene glycol. It is likely that the acid served as a catalyst to increase the hydrochar yield. This also reduced the oxygen content of the hydrochar leading to a higher calorific value. The study about producing high purity terephthalic acid from mixed cloth, needed one extra step to the process of removing dye from coloured polyethylene terephthalate bottles. The filtered HTC solid product needed heating without oxygen before being mixed with sodium hydroxide solution. After that, the other impurities, notably dyes, could be removed from the disodium terephthalate solution by activated carbon absorption as for the coloured PET bottles
Rational engineering of Apoferritin-based nanoparticles for drug delivery
Get PDFEffective drug delivery remains a major challenge in treating diseases like cancer, where targeted delivery systems are critical for maximizing efficacy and minimizing side effects. Drug delivery systems (DDS) offer a promising solution, and apoferritin, a protein-based nanoparticle, has shown considerable potential as a DDS due to its biocompatibility and capacity for drug encapsulation. However, the effectiveness of apoferritin for drug delivery is limited by the leakage of small drug molecules through its surface pores, which prevents drug accumulation at a target site. Addressing this challenge through the structural engineering of apoferritin’s pores could expand its utility, enabling it to encapsulate a wider range of therapeutic agents. This thesis aims to provide directives for potential pore modifications to optimise ferritin as a versatile nanocarrier capable of retaining even small, leakage-prone drugs. This is achieved through the use of in silico molecular dynamics simulations to minimise small molecule drug leakage by mutating the ferritin threefold and fourfold surface pores. The analysis of these modifications is supported by a streamlined protocol for the in silico analysis of mutants focusing on their structural stability and ability to minimise pore leakage. Preliminary experimental work is provided from which future work can validate these results in vitro
The Far-Reaching Impact of Cluster Environments on the Nuclear Activity and Star Formation of Galaxies
Get PDFThis thesis presents interlinked studies on radio and optical observational data, with the aim of understanding environmental effects on the star formation and nuclear activity of galaxies. These studies have been facilitated by the recent availability of large, deep radio surveys, enabling detailed investigations of galaxy properties across diverse environments. By combining these datasets with optical observations, this work explores how local and global environmental processes, such as ram pressure, galaxy density, and cluster-centric distance, influence the evolution of galaxies.
In Chapter 3, we investigate where, how, and why star formation quenching begins in the outskirts of galaxy clusters. Using the Low-Frequency Array (LOFAR) Two-metre Sky Survey, we analyse the de-projected radial distribution of star-forming galaxies (SFGs) out to 30R500, where R500 is the radius within which the average cluster density is 500 times the critical density of the Universe. We find that the SFG fraction begins to decline from the field fraction at 10R500, well beyond the cluster's virial radius. This decline is influenced by both large-scale (cluster-centric distance) and local (nearest-neighbour density) environments. Galaxies in high-density local environments show lower SFG fractions, but for high-mass galaxies -- and to a lesser extent, low-mass ones -- such environments can also shield SFGs from external quenching mechanisms in cluster outskirts. For galaxies in low-density local environments, quenching due to global environment dominates and acts independent of stellar mass. These results reveal a complex interplay between galaxy mass, local density, and global cluster-centric distance in regulating star formation.
In Chapter 4, we examine how the fraction of LOFAR-identified radio active galactic nuclei (AGN) varies with cluster-centric radius, analysing their projected and de-projected distributions out to 30R500. The AGN fraction shows distinct trends: a ~25% increase above the field fraction in the outskirts (~10R500), a ~20% suppression near ~0.5R500, and a sharp rise to over three times the field fraction in the cluster core. These regions reveal differences in host galaxy stellar mass and AGN radio luminosity. In the core, AGN preferentially reside in massive galaxies, while regions with higher AGN fractions generally host more luminous radio AGN. These findings highlight a dynamic relationship between environmental mechanisms and intrinsic galaxy properties in driving AGN activity.
In Chapter 5, we investigate the details of the interactions between radio galaxies and both the intracluster medium (ICM) and the intergalactic medium (IGM) by analysing 208 narrow-angle tail (NAT) radio sources detected by the LOFAR Two-metre Sky Survey. Within 7R500 of the cluster centre, NAT tails show a strongly anisotropic distribution, predominantly bending radially away, consistent with galaxies on inbound orbits. Closer to the cluster core (<0.5R500), we observe an excess of NATs with jets bent toward the centre, suggesting these sources fade after passing pericentre. For NATs with spectroscopic redshifts, this radial alignment persists out to 10R500, well beyond the virial radius. The presence of aligned NATs at such large distances implies significant deceleration of the inflowing intergalactic medium, sufficient to produce ram pressure capable of bending jets and potentially triggering radio emission.
In Chapter 6, we investigate the presence and effects of ram pressure on star formation outside galaxy clusters, through analysis of H-alpha emission in galaxies in the cluster Abell 1682 and its surrounding environment. Utilising data we obtained using the Wide Field Camera at the Isaac Newton Telescope, we identify and characterise 39 H-alpha-emitting sources across a field of view spanning ~7.4 x 7.4 Mpc. By comparing the spatial offsets between H-alpha and i-band emission, we detect a statistically significant preference for enhanced H-alpha-emission on the leading edges of galaxies, consistent with a scenario that suggests enhanced star-formation due to gas compression by ram pressure. Surprisingly, these effects are observed not only in the expected filamentary regions but throughout the cluster outskirts, as far as 7.7 Mpc from the cluster centre. These tentative findings challenge current models of gas density in cluster environments and suggest that the intracluster medium may extend further than previously thought, or that multiple filaments may contribute to the observed effects
Environmental design and thermal comfort in urban courtyards within different urban design patterns in Saudi Arabia
No full textUrban open space design and patterns play a vital role in shaping the microclimate of outdoor environments, significantly influencing user comfort and activities. In a harsh arid environment like that of Saudi Arabia, creating high-quality, thermally comfortable outdoor urban spaces is critical. However, studies have highlighted the lack of detailed policies for the environmental planning and design of outdoor urban spaces in Saudi cities, particularly in Makkah, contributing to increased thermal discomfort.
This research investigates the influence of alternative urban design patterns on the microclimate and thermal comfort of outdoor urban spaces in Makkah, as an example of a city in a hot-arid climate region. Using three types of courtyard at Umm Al-Qura University (semi-enclosed, partially-open with a canopy, and fully-enclosed), the study analyzes key urban design parameters, namely, orientation, aspect ratio, tree coverage, and mist system density and examines their impact on air temperature, RH, WS, mean radiant temperature (MRT) and physiological equivalent temperature (PET). Field measurements were conducted during extreme summer and winter conditions, with meteorological data outside the courtyards recorded for 10 days and microclimatic conditions inside each courtyard monitored for 48 hours. Numerical modelling using ENVI-met software was then used to simulate a series of proposed scenarios (seven for orientation, three for aspect ratio, five for tree coverage, and three for misting), which were then assessed against the base case data to identify the most effective options in each case.
The findings reveal that the impact of the design parameters varies by courtyard type. Orientation adjustments had the greatest influence on the fully-enclosed courtyard, where a 135° rotation reduced daily PET by 0.39°C in summer through improved shading. In contrast, the partially-open courtyard benefitted most from orientation changes that enhanced airflow, reducing PET by 0.15°C in winter. Aspect ratio changes were particularly effective in the semi-enclosed courtyard, where increasing the height-to-width ratio to 0.75 H/W lowered PET by 1.08°C in winter and 0.41°C in summer, due to enhanced shading, without significant airflow restriction. The fully-enclosed courtyard and the partially-open courtyard with the structural canopy benefitted more from the lowest aspect ratio (0.25 H/W), as this enhanced airflow and reduced PET. In winter, the most significant PET reduction occurred in the fully-enclosed courtyard with a low aspect ratio (0.25 H/W), achieving a daily PET reduction of 1.34°C, driven by an increase in WS of 0.66 m/s.
Tree coverage was found to provide substantial cooling across all courtyard types, with 30% coverage reducing PET by 2.34°C in summer and 2.78°C in winter in the fully-enclosed courtyard. The semi-enclosed courtyard experienced a PET reduction of 1.46°C in summer, while the partially-open courtyard with the canopy showed more moderate reductions due to the pre-existing shade. High-density mist systems (2-meter intervals) proved most effective in reducing PET during summer, with the semi-enclosed courtyard showing the largest reduction of 7.61°C, followed by the fully-enclosed courtyard at 6.98°C. However, excessive humidity in enclosed spaces during winter required balancing mist density to prevent discomfort.
These findings are used to develop actionable urban design guidelines for architects and urban designers to promote the efficient use of orientation and aspect ratios to optimise shading and airflow and to ensure that tree coverage and mist systems are utilised most effectively. Recommendations for policy-makers are also provided to create a holistic framework to support the use of urban design to enhance outdoor thermal comfort in Makkah. This research therefore contributes to sustainable urban planning in hot-arid climates by offering practical strategies to reduce thermal stress and mitigate rising temperatures caused by climate change. At the local level it offers solutions to create more comfortable outdoor environments in Makkah and in other Saudi cities, aligning with the goals of Saudi Vision 2030. At an international level, the findings will also be of benefit in other regions which experience similar climatic conditions
Investigating ApoE4-Mediated Molecular Alterations in H4 Neuroglioma Cells of Alzheimer’s Disease Using OrbiSIMS and LC-MS/MS.
Get PDFApolipoprotein E4 (ApoE4) is the significant risk gene for late-onset Alzheimer’s disease (AD), which is not only associated with the AD pathological features, including amyloid-β deposition, phosphorylation of Tau proteins and neuroinflammation; but also involved with metabolism, neuron growth, and synaptic plasticity. Growing clinical evidence has revealed that dysfunction of systematic molecular alterations in the brain occurs even twenty years before the onset of AD pathological features. Multi-omics such as metabolomics and proteomics have been applied widely in identifying key disease-related molecular alteration and disease-progression-related changes. Despite recent advances in the development of analytical technologies, screening the whole profile of metabolites remains challenging, due to many classes of compounds with diverse chemical properties that would need different extraction processes.
In this study, we combined two omics (metabolomics and proteomics) to study the molecular alteration effected by ApoE4 in H4 neuroglioma cells. Typically, we first conducted metabolomics that uses Orbital trapping secondary ion mass spectrometry (OrbiSIMS) as a screening tool to gain a non-biased overview of metabolic alteration under ApoE4-carried neuroglioma cells. Sample preparation optimisation for H4 cells in OrbiSIMS analysis has been conducted under two conditions: freeze-dried and frozen-hydrated. The findings are subsequently followed by LC-MS/MS targeted metabolomics for further confirming specific metabolite classes. Then proteomics was also performed by using UHPLC-MS. Subsequentially, Gene ontology (GO) analysis has been applied to link the metabolomics and proteomics results.
The initial OrbiSIMS approach has shown the advantages of detecting large numbers of metabolites with minimal sample preparation, small sample size and a relatively rapid analysis time, allowing 192 putatively annotated metabolites detected in our study. Overall, OrbiSIMS as screening tool then followed by LC-MS/MS is successfully developed to investigate cellular metabolomics, revealing the disruption of lipid metabolism (glycerophospholipids and sphingolipids) and amino acid metabolism. This includes alanine, aspartate, and glutamate metabolism, aminoacyl-tRNA biosynthesis, glutamine metabolism, and taurine and hypotaurine metabolism. Proteomics study further confirms the dysfunction of amino acids, tRNA aminoacylation metabolic processes, and reveals RNA splicing process affected by ApoE4. GO analysis suggests that nitrogen compounds, amino acids, tRNA aminoacylation metabolic processes play important roles in ApoE4 mediated molecular alterations in AD
Imaging and analysis of single atoms and molecules by transmission electron microscopy
No full textThe transmission electron microscope (TEM) is a powerful tool that can resolve the positions of individual atoms within a material. Measurement of the position and motion of single atoms via TEM imaging and spectroscopy provides understanding of how matter behaves at the fundamental level, without relying on bulk measurements averaged over many particles. Further, the high energy electron beam can initiate chemical transformations within the microscope, which can be imaged in real time with high spatial resolution.
In this thesis, the TEM is used to study the behaviour of individual atoms of the noble gases (Ng) krypton, argon and neon. Ng atoms were inserted into the cavities of fullerene cages, which were in turn encapsulated by single-walled carbon nanotubes (SWCNT), to form electron transparent materials that are sufficiently stable under electron irradiation, and hence suitable for single atom studies within the TEM. The resultant linear “endohedral peapods” were thoroughly characterised by TEM imaging and spectroscopy, including the properties of individual Ng atoms such as scattering strength and motion within the fullerene cage. Controlled energy transfer from the electron beam was applied to selectively coalesce fullerene molecules within SWCNT to form 2Ng@C120 species, within which the bonding states of Ng2 dimers were probed via time-resolved TEM imaging. Application of Lennard-Jones empirical potential models to these systems was used to rationalise observed atomic behaviour, including van der Waals bonding. The behaviour of different Ng atoms could be discriminated by their relative atomic sizes, masses and polarisabilities. Application of heat to noble gas endohedral peapods led to the formation of “nested nanotube” containers. Within these containers, guest Ng atoms became able to translate along a single axis, and hence transitioned to a state similar to a one-dimensional gas. Cooling of this gas in the TEM revealed a reversible transition between gaseous and atomic chain states, akin to a 1D thermal phase transition.
A variety of analysis methods are utilised for imaging and chemical identification, including bright field high-resolution TEM (BF-HRTEM) imaging, annular dark field scanning TEM (ADF-STEM) imaging, energy dispersive X-ray
spectroscopy (EDS), STEM electron energy loss spectroscopic (STEM-EELS) mapping, and cryogenic TEM (cryo-TEM) imaging. Bulk analysis by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) also provided valuable information on the structure of the host SWCNT and guest Ng atoms, respectively.
This work advances our understanding of single atom behaviour and of electron beam-matter interactions, including dispersion interactions, bond formation and breaking, and the behaviour of dimensionally constrained matter
Developing an understanding of redox-shuttle mediators in lithium-metal batteries
No full textThe lithium-ion battery (LIB) is widely acknowledged as the state-of-the-art battery technology in use today and is used in consumer electronics, stationary storage, and electrified transportation. However, there is a drive towards developing technologies with higher energy densities. The lithium-sulfur (Li-S) and lithium-air (Li-air) batteries are two of the most promising next-generation technologies for high-energy applications, due to their high theoretical gravimetric energy densities, low raw material costs, and reduced environmental impact. Despite these potential advantages, both devices are still beset with difficulties, one of the more severe being the formation of insulating products during discharge of the battery. This leads to high overpotentials on charge, low active material utilisation, culminating in poor coulombic efficiencies and rapid cycle life decay. Redox mediators (RMs) have been touted in both systems as a solution to oxidise the insulating discharge products and overall improve the sluggish kinetics of the discharge/charge reactions.
The first half of this thesis, particularly Chapter 3, will focus on developing a structure-property relationship between redox mediators and their ability to target specific reactions in the Li-S battery. Their interaction with sulfur, lithium sulfide, lithium polysulfide and lithium metal will be better understood using a variety of techniques. Using liquid chromatography demonstrates there is a relationship between the redox potential of a mediator and its ability to drive certain sulfur redox processes. For example, high potential mediators are better able to drive Li2S oxidation to form S8, whereas mediators with lower redox potentials drive S8 reduction to lower chain polysulfides. This study also emphasises the redox potential alone is not a reliable indicator of the performance of the mediator, as lithium metal is shown to react with these molecules, leading to undesirable side effects in the battery. This has been proven using UME voltammetry, where some mediators undergo irreversible decomposition in contact with lithium.
In the second half of this thesis, in Chapter 4, a new redox mediator for the Li air charge process will be proposed. This molecule is capable of driving Li2O2 oxidation at potentials well before solvent degradation onset. In the literature, using Marcus theory, it is also suggested to have high kinetics in oxidising Li2O2 as its redox potential lies in the appropriate range. The importance of structural stability for RMs will be highlighted, as a simpler redox mediator structure is shown to undergo deprotonation in the cell, which leads to rapid capacity fade and premature cell death. Therefore, design principles will be established to create more stable, effective redox mediators in the desired voltage window. A variety of techniques, such as differential electrochemical mass spectrometry, cyclic voltammetry and galvanostatic cycling will be used to justify mediator performance.
In Chapter 5, a novel gas-handling demonstrator system will also be developed, where the effect of flow rate, gas composition and partial pressure of O2 will be explored on a closed Li-air flow cell. It is shown these factors lead to significant consequences for a practical Li-air cell, as capacities of the cell are severely impacted on moving to lower flow rates and partial pressures of O2
Blooming blanket weed: occurrence, impacts and environmental drivers of nuisance filamentous green algal blooms in shallow freshwaters
No full textBlooms of filamentous green algae (FGA) form dense mats at the surface of shallow freshwaters and have multiple negative impacts on aquatic ecosystem functions, services and aesthetics. Effective management and control of FGA blooms is therefore a pressing issue. However, their spatial and temporal dynamics and associated environmental conditions remain under researched, especially in shallow freshwater ecosystems. This thesis aimed to address this knowledge gap by: 1) exploring the occurrence, impacts and current management of FGA blooms at the national scale using survey and citizen science data; 2) investigating the spatial and temporal dynamics of FGA growth and bloom presence and associated environmental conditions over a 19-month monitoring period in Clumber Lake, Nottinghamshire, UK, a shallow ornamental lake managed by the National Trust, 3) examining how light and temperature affect FGA surface bloom formation in nutrient-replete conditions in a series of large-scale mesocosm experiments using underwater and surface photography; and 4) assessing whether FGA function as ecological engineers in Clumber Lake.
The survey and citizen science data revealed that FGA blooms are occurring across the UK in shallow standing freshwater bodies, are generally found at lower elevations, and have a wide range of impacts on both ecology and people. These impacts depends on the waterbody’s uses and functions, as people place different values on different waterbodies and the ecosystem services they provide. Successful management of FGA blooms requires a collaborative approach at the catchment scale to reduce nutrient loading into freshwater systems, but short-term measures, such as FGA removal, are sometimes necessary to enable ecosystem service provision.
Monthly limnological monitoring at Clumber Lake revealed Cladophora spp. was the dominant FGA taxon, which grew all year round in the benthic zone. Surface blooms occurred between April – September, generally coinciding with increases in benthic FGA biomass. They were dominated by Ulva sp. early in the season in the shallowest areas of the lake, followed by Cladophora later in the season across the whole lake. High loads of phosphorus and nitrogen enter Clumber Lake from the surrounding Poulter catchment (127km2), and nutrient addition bioassay experiments confirmed that FGA growth was never limited by nutrient availability over a seasonal cycle. Nitrate and total nitrogen concentrations significantly affected the likelihood of surface bloom presence and benthic FGA biomass, respectively, whilst daylength and monthly sunshine hours were both significant predictors of surface bloom presence. We established that Clumber Lake exists in an FGA-dominated clear-water state, most likely enabled by rapid lake flushing rates that prevent the accumulation of phytoplankton biomass, limiting their ability to compete with FGA which remain in the lake and utilise incoming nutrients. The FGA also function as ecological engineers in Clumber Lake by altering nutrient cycling and environmental conditions in the water column, including light, dissolved oxygen and pH. They also providing refuge, substrate and/or food for macroinvertebrates, functionally compensating for the lack of macrophytes.
At the experimental scale, a minimum threshold of daily light dose of ~55.0 mol m-2 (a combination of photoperiod and irradiance) was required for bloom formation and substantial FGA growth. Surface blooms did not occur during shorter photoperiods (i.e. 8 hours), suggesting daylength is a limiting factor. A longer daylength allowed more time for photosynthetically-derived gas bubbles to accrue in the FGA masses, making them buoyant and float to the water surface. Temperatures between 16-22 °C were also optimal for FGA to form surface blooms. With the increasing impact of climate change on freshwater ecosystems, these results shed new light on the drivers of surface blooms and helps predict when waterbodies may be at risk of FGA blooms in the future.
Overall, this research demonstrates that FGA blooms are common in shallow freshwater bodies, and whilst their growth is primarily driven by nutrient pollution, surface bloom formation is dependent on specific light and daylength requirements within certain temperature ranges. Management strategies should focus on reducing nutrient loading by working collaboratively at the catchment scale. These results can also be used to help predict FGA bloom occurrence in order to focus management efforts and resources. It is vital that the impacts of management are monitored and quantified to build a greater evidence base that can be used to inform successful FGA management in the future
Baselining small mammal communities at a rewilding project
Get PDFAs one of the most nature-depleted countries in the world, and one of the European countries with the lowest proportional forest cover, the UK is especially negatively impacted by the consequences of the global biodiversity crisis. Increasingly, rewilding is seen as a method of addressing this issue. The creation of rewilding sites across the UK will inevitably alter the flora and fauna at any given site. Such ecological changes will need to be monitored over time and compared to a baseline to evaluate the success of rewilding projects. This study aims to monitor the changes in small mammal populations across Boothby Wildland, a 617-hectare arable farm on grade 3 land in Lincolnshire that recently began taking steps towards rewilding. The site has been gradually reducing agricultural production since 2022; thus, the site contains fields which are still being actively farmed, and areas which are being subjected to passive rewilding. Small mammals are an ecologically important taxon, that are often overlooked in conservation projects. By studying their responses to spatial and temporal changes in habitat, insight can be gained into how small mammals respond during the early stages of rewilding projects. The main method of monitoring occurred via 6 x 5 grids of Longworth traps across nine months and 70 trapping nights amongst fields withdrawn from agriculture for varying periods. Hedgerows were also monitored. The traps were checked twice a day, and measurements, including species, weight, and sex were taken, before mark and release via fur clippings. Audio equipment was also placed in these trapping grids. This was to test the effectiveness of different survey methods at measuring biodiversity, and as a means of providing a supplementary form of monitoring. The greatest small mammal diversity was found in the hedgerows, confirming their importance as a habitat feature. The majority of catches were dominated by wood mice (Apodemus sylvaticus), which made up 509 of the 524 total catches (97.14%), with the remaining 15 catches consisting of 8 field voles , 5 common shrews, 1 pygmy shrew, and 1 harvest mouse. Small mammal populations appeared to reflect typical annual cycles, i.e. greater abundance in the autumn and considerably fewer individuals in the spring. Audio data corroborated the Longworth trapping with regards to November being the greatest month for activity across all species. The fewest small mammals were found, in both Longworth traps and Audio recordings in bare fields, demonstrating a shift in small mammal communities as agricultural fields are taken out of production and vegetation is altered in rewilding projects. These data can be used to inform new rewilding projects of the way small mammals may respond to initial management
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