SPATIAL AND TEMPORAL DYNAMICS OF FINE FLUVIAL SEDIMENT TRANSFER: IMPLICATIONS FOR MONITORING AND MANAGEMENT OF UPLAND RIVER SYSTEMS

Although the impacts of changing land use on the magnitude and timing of erosion in lowland catchments are well documented, much less is known about the transfer dynamics of fine sediment through the upland hydrological networks. Using a novel distributed monitoring approach, this thesis examines the magnitude, timing and physical characteristics of fluvial fine sediment in two adjacent upland rivers in North Yorkshire (UK). Annual suspended sediment yield (SSY) estimates range from 33.92 t km-2 in the 131 km2 Upper Derwent catchment to 57.91 t km-2 in the 96 km2 River Esk catchment. Infrequent events were found to be of greatest importance, transferring up to 38% of the annual load in under two days. Simple annual and seasonal rating curves were constructed and are effective in predicting SSC with relative errors of less than 15%. Analysis of within-storm fine sediment dynamics indicated the dominance of sources proximal to the channel in the Esk catchment, whereas sediment sources in the Upper Derwent were more variable. Distributed time-integrated fine sediment sampling identified high SSYs in the headwaters of the Upper Derwent whereas in the headwaters of the Esk the minimum SSY was found with tributaries draining the central valley having maximum SSYs. Analysis of the absolute particle size observed significant downstream fining in both catchments and strong positive relationships between flow and particle size of the transported sediment. The data collected are also applied to four real-world scenarios to demonstrate the effectiveness of this approach. This research has enhanced our understanding of fine sediment delivery to upland channels through the assessment of the fine sediment dynamics at a range of temporal and spatial scales rarely studied in these environments

Developing a Community: Qualitative Approaches to Understanding the Role of Community Engagement in Gameswork

Through multiple qualitative approaches, this dissertation contributes to understanding the increased role of addressing, engaging, and managing online communities in gameswork. It pays particular attention to how individual actors – such as game developers, content creators, community managers, and game journalists – collectively react to shifting industry trends that prioritize community engagement and building. It contributes to the literature on games by highlighting the experiences and perspectives of those working within the industry – such as community managers and game developers – as their industry undergoes significant shifts in priorities. In addition, it contributes to media and platform studies by examining the impacts on the production and consumption of media when audiences demand more intimate and direct access to creators. It pays specific attention to the workers who act as the filter between those who produce and those who consume. This dissertation draws together four individual projects with distinct methodologies, research partners, and questions to illustrate the impacts of this shift. Chapter 2 examines critical games journalism to show how a lack of investment in community engagement leads to a breakdown of the community. Chapter 3 uses qualitative interviews and observation of drag content creators to show how they grapple with building their online communities amidst changing platform dynamics. Chapter 4 uses qualitative interviews with game developers to highlight how they choose to or choose not to work with content creators as they adapt to new priorities in their industry. Chapter 5 uses qualitative interviews with community managers to examine how their work has changed, continues to change, and leaves lingering anxieties and questions about the future of their work. These individual projects are tied together through the complementary theme of servitization (Vandermerwe & Rada, 1988; Weststar & Dubois, 2022), which captures the trend of traditionally individually produced, packaged, and consumed products moving to a system of continuous access and consumption. As gameswork produces more products designed as a service for consumers, it changes the needs and expectations of gaming communities. I argue that this increased emphasis on community changes priorities for those working within creative and cultural industries that have implications for developers, community managers, and players. As these priorities change, new concerns arise regarding the working conditions, career, and educational pathways for those in community-focused roles

Identifying the optimal spatial distribution of tracers for optical sensing of stream surface flow

River monitoring is of particular interest as a society that faces increasingly complex water management issues. Emerging technologies have contributed to opening new avenues for improving our monitoring capabilities but have also generated new challenges for the harmonised use of devices and algorithms. In this context, optical-sensing techniques for stream surface flow velocities are strongly influenced by tracer characteristics such as seeding density and their spatial distribution. Therefore, a principal research goal is the identification of how these properties affect the accuracy of such methods. To this aim, numerical simulations were performed to consider different levels of tracer clustering, particle colour (in terms of greyscale intensity), seeding density, and background noise. Two widely used image-velocimetry algorithms were adopted: (i) particle-tracking velocimetry (PTV) and (ii) particle image velocimetry (PIV). A descriptor of the seeding characteristics (based on seeding density and tracer clustering) was introduced based on a newly developed metric called the Seeding Distribution Index (SDI). This index can be approximated and used in practice as SDI = nu(0.1)/(rho/rho(c nu 1)), where nu, rho, and rho(c nu 1 )are the spatial-clustering level, the seeding density, and the reference seeding density at nu = 1, respectively. A reduction in image-velocimetry errors was systematically observed for lower values of the SDI; therefore, the optimal frame window (i.e. a subset of the video image sequence) was defined as the one that minimises the SDI. In addition to numerical analyses, a field case study on the Basento river (located in southern Italy) was considered as a proof of concept of the proposed framework. Field results corroborated numerical findings, and error reductions of about 15.9 % and 16.1 % were calculated - using PTV and PIV, respectively - by employing the optimal frame window

Critical assessment and validation of a time-integrating fluvial suspended sediment sampler

Delivery of fine sediment to fluvial systems is of considerable concern given the physical and ecological impacts of elevated levels in drainage networks. Although it is possible to measure the transfer of fine sediment at high frequency by using a range of surrogate and automated technologies, the demands for assessing sediment flux and sediment properties at multiple spatially distributed locations across catchments can often not be met using established sampling techniques. The time-integrated mass-flux sampler (TIMS) has the potential to bridge this gap and further our understanding of fine sediment delivery in fluvial systems. However, these devices have undergone limited testing in the field. The aim of this paper was to provide a critical validation of TIMS as a technique for assessing fluvial fine sediment transfer. Fine sediment flux and sediment properties were assessed over 2 years with individual sampling periods of approximately 30 days. Underestimation of sediment flux ranged between 66% and 99% demonstrating that TIMS is unsuitable for assessing absolute sediment loads. However, assessment of relative efficiency showed that six of seven samplers produced statistically strong relationships with the reference sediment load (P < 0.05). Aggregated data from all sites produced a highly significant relationship between reference and TIMS loads (R2 = 0.80; P < 0.001) demonstrating TIMS may be suitable for characterizing patterns of suspended sediment transfer. Testing also illustrated a consistency in sediment properties between multiple samplers in the same channel cross section. TIMS offers a useful means of assessing spatial and temporal patterns of fine sediment transfer across catchments where expensive monitoring frameworks cannot be commissioned

Hydro-morphological mapping of river reaches using videos captured with UAS

Unoccupied aerial systems (UASs) are frequently used in the field of fluvial geomorphology due to their capabilities for observing the continuum rather than single sample points. We introduce a (semi-)automatic workflow to measure river bathymetry and surface flow velocities of entire river reaches at high resolution, based on UAS videos and imagery. Video frame filtering improved the visibility of the riverbed using frame co-registration and averaging with a median filter. Subsequently, these video frames were incorporated with still images acquired by UASs into a structure from motion (SfM) photogrammetry approach to reconstruct the camera poses (i.e. positions and orientations) and the 3D point cloud of the river reach. The heights of submerged points were further processed using small-angle and multi-view refraction correction approaches to account for the refraction impact. The flow velocity pattern of the river surface was measured using the estimated camera pose from SfM, the reconstructed bathymetric point cloud and the co-registered video frames in combination with image velocimetry analysis. Finally, discharge was estimated at selected cross-sections, considering the average surface velocity and the bathymetry. Three case studies were considered to assess the performance of the workflow under different environmental conditions. The studied river reaches spanned a length between 0.15 and 1 km. The bathymetry was reconstructed with average deviations to RTK-GNSS point measurements as low as 1 cm with a standard deviation of 6 cm. If frames were processed with the median filter, the number of underwater points increased by up to 21%. The image-based surface velocities revealed an average deviation to reference measurements between 0.05 and 0.08 m s(-1). The image-based discharge was estimated with deviations to ADCP references of up to 5%, however this was sensitive to errors in water-level retrieval. The output of our workflow can provide a valuable input to hydro-morphological models.</p

Investigating the impact of a clinical pharmacist on the health outcomes of a paediatric pharmacists

Background: Recent fiscal scrutiny and changes in health care financing have necessitated that health care providers justify a clinical and economical basis for their involvement in patient care. Although clinical pharmacists have been shown to enhance patient health outcomes and reduce costs among adult patients, the impact of a pharmacist in paediatric patient care has not been extensively documented. Method: A team of pharmacists was established to conduct a systematic review of the literature. A title scan of papers in 5 databases was performed by 14 pharmacists using the MeSH terms Pharmacists, Medical Intervention, Paediatrics and Cost-Benefit Analysis. The underpinning research question was: "How do the professional activities of a clinical pharmacist impact the health outcomes of paediatric in-patients?" The abstracts of suitable titles were scanned and articles were read to assess relevance. Relevant articles were then evaluated independently by at least two members of the team, using critical appraisal tools suitable for quantitative, qualitative or systematic review studies. Results: The initial search identified 327 citations which after full text review and application of the scoring tool, resulted in 12 studies included in the systematic review. The average number of interventions reported varied from study to study. Dosing recommendations, pharmacokinetics and drug allergy alerts were the most commonly recorded interventions by pharmacists for a paediatric population. Evidence from this review will be used to formulate improvements to in-patient paediatric care. Conclusion: Clinical pharmacists have a positive impact on inpatient paediatric care

Rapid Detection of the Change in Surface Flow Patterns Near Fish Passages at Hydropower Dams With the Use of UAS Based Videos Under Controlled Discharge Conditions

The importance of keeping river environments healthy drives the scientific community towards the improvement of sustainable and validated environmental monitoring approaches. Accurate data on the state of the ecosystems provided rapidly are key in order to correctly assess, which interventions and management decisions are suitable, and which must be avoided. This paper analyses a rapid non-intrusive approach to change detection in surface flow patterns near fish passages at hydropower dams with the goal to improve the understanding of factors influencing fish passage discoverability. This, in turn, is of great relevance to the sustainability of migrating riverine fish populations from both ecological and economical perspectives. The present study includes three unique experiments performed at a large-scale hydropower dam site with an integrated fish passage under controlled discharge conditions. The analysis is performed with the use of the freely available KLT-IV software. The use of an Unmanned Aerial System (UAS) as a camera carrier platform provides the key flexibility in terms of any study site selection. The use of KLT-IV speeds up and simplifies flow pattern analysis, especially when compared to labour-intensive modelling relying on point-based ground truth data. In this paper, we demonstrate that the selected approach can be effectively applied to identify changes in surface flow patterns both in terms of flow velocity magnitudes and in terms of flow directions. It shows that the identification of actual flow patterns near the fish passage entrance provides more information on the potential discoverability of the fish passage than traditionally measured bulk discharge values alone

Recommendations for improving integration in national end-to-end flood forecasting systems: an overview of the FFIR (flooding from intense rainfall) programme

Recent surface-water and flash floods have caused millions of pounds worth of damage in the UK. These events form rapidly and are difficult to predict due to their short-lived and localised nature. The interdisciplinary Flooding From Intense Rainfall (FFIR) programme investigated the feasibility of enhancing the integration of an end-to-end forecasting system for flash and surface-water floods to help increase the lead time for warnings for these events. Here we propose developments to the integration of an operational end-to-end forecasting system based on the findings of the FFIR programme. The suggested developments include methods to improve radar-derived rainfall rates and understanding of the uncertainty in the position of intense rainfall in weather forecasts; the addition of hydraulic modelling components; and novel education techniques to help lead to effective dissemination of flood warnings. We make recommendations for future advances such as research into the propagation of uncertainty throughout the forecast chain. We further propose the creation of closer bonds to the end users to allow for an improved, integrated, end-to-end forecasting system that is easily accessible for users and end users alike, and will ultimately help mitigate the impacts of flooding from intense rainfall by informed and timely action

On the Use of Unmanned Aerial Systems for Environmental Monitoring

Environmental monitoring plays a central role in diagnosing climate and management impacts on natural and agricultural systems; enhancing the understanding of hydrological processes; optimizing the allocation and distribution of water resources; and assessing, forecasting, and even preventing natural disasters. Nowadays, most monitoring and data collection systems are based upon a combination of ground-based measurements, manned airborne sensors, and satellite observations. These data are utilized in describing both small- and large-scale processes, but have spatiotemporal constraints inherent to each respective collection system. Bridging the unique spatial and temporal divides that limit current monitoring platforms is key to improving our understanding of environmental systems. In this context, Unmanned Aerial Systems (UAS) have considerable potential to radically improve environmental monitoring. UAS-mounted sensors offer an extraordinary opportunity to bridge the existing gap between field observations and traditional air- and space-borne remote sensing, by providing high spatial detail over relatively large areas in a cost-effective way and an entirely new capacity for enhanced temporal retrieval. As well as showcasing recent advances in the field, there is also a need to identify and understand the potential limitations of UAS technology. For these platforms to reach their monitoring potential, a wide spectrum of unresolved issues and application-specific challenges require focused community attention. Indeed, to leverage the full potential of UAS-based approaches, sensing technologies, measurement protocols, postprocessing techniques, retrieval algorithms, and evaluation techniques need to be harmonized. The aim of this paper is to provide an overview of the existing research and applications of UAS in natural and agricultural ecosystem monitoring in order to identify future directions, applications, developments, and challengespublishersversionPeer reviewe