Nutrients

While vital for the survival of all organisms, nutrients can also pose a threat to aquatic life. Surplus nutrients from agriculture and sewage can cause excess growth of plant life and algae in a process called eutrophication. Eutrophication can have various damaging ecological impacts, including low DO, blocking light from the water column, and blooms of toxic blue-green algae

Using technology to promote social connectedness: Insights from the T&Scon project

Loneliness and social isolation can affect anyone, with policymakers recognising the impact of isolation on individual wellbeing and public health. In 2018 the Scottish Government set out its approach to tackling social isolation in A Connected Scotland, a national strategy to achieve a Scotland “where individuals and communities are more connected, and everyone has the opportunity to develop meaningful relationships regardless of age, stage, circumstances, or identity.” A priority of the strategy is to create opportunities for people to connect, with a specific commitment to work with older age groups to “understand how digital technology can add value to their lives in a way that is meaningful”, informing wider work to deliver the Scottish Government’s Digital Strategy for Scotland. The Technology and Social Connectedness (T&Scon) project explored the potential of technology to support social connectedness for adults living in Scotland, producing a toolkit to provide guidance for individuals and organisations on the use of digital technology in building and maintaining social connections. This briefing paper, drawing on the project’s key findings and recommendations, provides a summary of key information for policymakers and practitioners in Scotland, and further afield. Its findings will be of particular interest to those who are developing new ways of keeping in touch, as the risk of social isolation becomes more pronounced in the wake of the global coronavirus pandemic. Key findings A wide range of UK and international technology-based and technology-enabled services exist, designed to support social connectedness, targeted at different adult age user groups. Most technologies used in this way are intended for people living at home although there are technologies in use and in development for the care home sector. Data from the Healthy Ageing in Scotland (HAGIS) study revealed patterns of social connectedness among people over the age of 50 living across Scotland. Patterns of technology use across different groups suggest that those who are least socially connected may also be those least likely to utilise technology to connect with others. Careful evaluation of the target user group is an important factor in the successful adoption of technology-based solutions, breaking down assumptions about who uses technology and who doesn’t, and understanding the risks and opportunities of using technology for this purpose.Briefing based on: T&SCon: Technology and Social Connectedness, Final Report, available online at http://www.tec.sco

Climate change and eutrophication risk thresholds in English rivers

Climate change is expected to alter water quality in rivers, but where and when this may happen is uncertain. This report describes a study of projected response in the amount of algal plant growth (phytoplankton biomass). Increasing algal growth is one of the ecological manifestations of eutrophication in slow flowing rivers, where the water starts to resemble a green soup. Eutrophication is a process in which too much nutrient in water causes algae and higher plants to grow excessively. Eutrophication alters the quality of the water and how it can be used. Phytoplankton (suspended algae) is considered to be a useful indicator of eutrophication in standing freshwaters and can also be useful as one measure of impacts in rivers, particularly slow flowing rivers. Excess algal growth can result in blooms that eventually die off. The disruption of dissolved oxygen dynamics in the water column may, in turn, have adverse impacts on fish and macroinvertebrates. The onset and decline of algal blooms is measured by the concentration of chlorophyll (a green pigment in algae) in the water. In this context, algal bloom risk – and the risk of negative eutrophication impacts in the lower reaches of rivers – is identified through observations of threshold chlorophyll concentrations. Exceedence of a chlorophyll concentration threshold is not by itself used in the diagnosis of river eutrophication but can be used as a proxy for algal blooms for understanding and modelling risk. The future risk of eutrophication impact, including algal blooms, is affected by changes in the concentration of nutrients from altered river flow and changes in phosphorus inputs from a range of sources. An earlier study (Phase 1 of this project) demonstrated that climate change impacts on river flow would increase phosphorus concentrations by 2050 and beyond. However, climate-driven changes in river temperature regime and light, and plant responses to these, are also important in altering the future risk of excess algal growth. This report considers these aspects. The first step was to identify the variables that control eutrophication and the thresholds in these variables which determine the potential for algal blooms. Algal blooms tend to occur only in rivers with a residence time (the time water takes to travel from an upstream distance to a site) of over 4 days. Below 4 days, blooms are rare. Such long residence times in the UK tend to occur in canals, and slow flowing and shallow gradient rivers (often in their lower reaches). Using this residence time threshold of 4 days, a total of 26 sites in England on 24 different rivers with available data for analysis of trends were identified out of the 115 sites from Phase 1. Water quality data were used to identify the ranges of river flow and water temperature within which algal blooms were measured (as determined by chlorophyll concentration) for each site. Site-specific thresholds were identified from plots of variables of water quality against chlorophyll concentration. In this study, a chlorophyll threshold of 30µgl-1 indicated the onset of an algal bloom for most rivers. Thresholds ranged between 15µgl-1 and 100µgl-1 . For larger rivers, with higher chlorophyll levels (such as the Thames), the thresholds for algal blooms are higher. A phosphorus threshold of 30µgl-1 was selected for all sites, based on understanding developed through nutrient limitation experiments across a range of UK rivers in other studies. A sunlight duration threshold of 65W/m2 /day was chosen for all the sites based on a minimum of at least 3 hours of full sunshine per day over ~3 consecutive days (derived from earlier work). A bloom is likely to occur if all thresholds are met at the same time. These are called bloom risk days and they represent overall risk based on all measured variables. A spreadsheet model was developed and applied to the 26 sites. The model used daily estimates of controlling variables (phosphorus concentrations, river flow, water Climate change and eutrophication risk thresholds in English rivers v temperature and sunlight duration) from 1951 to 2098 to estimate when the derived thresholds for each variable were met and likely to cause an algal bloom. Phosphorus concentration estimates from earlier work were used under current wastewater treatment conditions and under an improved wastewater treatment scenario. Bloom risk days (when the river flow, water temperature, sunshine duration and phosphorus concentration thresholds for algal growth were all met) increased between the baseline period (1961 to 1990) and the 2050s future period (2040 to 2069). The median increase is about 8 days across all sites from about 50 in the baseline period, although the maximum increase is up to 15 days. The change in risk is variable by the 2080s (2070 to 2098), with about 50% of sites showing reduced risk relative to the baseline period, resulting in a median increase of about 4 days and a maximum of up to 16 days. Analysis of the number of threshold days for each individual driver indicates that phosphorus thresholds are met most days of the year and that phosphorus concentrations do not prevent bloom development except at one site. Phosphorus management strategies may therefore not be effective in reducing the risk of algal blooms occurring in slow flowing rivers, an observation confirmed by the fact only 3 sites showed a reduction in risk using an improved phosphorus treatment scenario. There is more variability in the number of days the other thresholds are met, resulting in a varying pattern of risk between sites and time periods. After phosphorus concentration thresholds, river flow thresholds are most frequently met. Sunlight duration and water temperature thresholds are least often met. The interaction between flow variability, water temperature and sunlight duration would appear to determine the variability that emerges by the 2080s. The role of water temperature and sunlight duration seems to be significant in both limiting the number of days all thresholds are met and in controlling the timing of attainment of all thresholds, with both thresholds tending to be exceeded later in the year than those for river flow and phosphorus concentration. With the lowest number of threshold days at the greatest number of sites, exposure to sunlight may be the most important factor in preventing algal blooms. There is considerable uncertainty in the estimation of future water temperature, which was derived from air temperature using simple regression methods. This may result in a variable estimate of bloom risk days that requires further exploration with more reliable projections of future water temperature. A better way of estimating water temperature would really help to model future water quality. These results suggest that management strategies focusing on reducing sunlight and thermal interactions (both through river shading by trees) may be particularly effective in reducing the risk of blooms on some rivers in the future. This could be explored using the spreadsheet model developed for this project. Whilst phytoplankton blooms tend to be observed in lowland reaches of English rivers, the approach applied here is independent of this, is equally applicable anywhere, and has potential for use in an approach for assessing eutrophication in slow flowing rivers. It would also be useful to identify more sites across England at which residence time thresholds are met in order to assess potential vulnerability to eutrophication

Qualitative impact assessment of land management interventions on ecosystem services (“QEIA”). Report-3 theme-4: water

This project assessed the impacts of 741 potential land management actions, suitable for agricultural land in England, on the Farming & Countryside Programme’s Environmental Objectives (and therefore Environment Act targets and climate commitments) through 53 relevant environmental and cultural service indicators. The project used a combination of expert opinion and rapid evidence reviews, which included 1000+ pages of evidence in 10 separate reports with reference to over 2400 published studies, and an Integrated Assessment comprising expert-derived qualitative impact scores. The project has ensured that ELM schemes are evidence-based, offer good value for money, and contribute to SoS priorities for farming

The impact of sequencing depth on the inferred taxonomic composition and AMR gene content of metagenomic samples

Shotgun metagenomics is increasingly used to characterise microbial communities, particularly for the investigation of antimicrobial resistance (AMR) in different animal and environmental contexts. There are many different approaches for inferring the taxonomic composition and AMR gene content of complex community samples from shotgun metagenomic data, but there has been little work establishing the optimum sequencing depth, data processing and analysis methods for these samples. In this study we used shotgun metagenomics and sequencing of cultured isolates from the same samples to address these issues. We sampled three potential environmental AMR gene reservoirs (pig caeca, river sediment, effluent) and sequenced samples with shotgun metagenomics at high depth (~ 200 million reads per sample). Alongside this, we cultured single-colony isolates of Enterobacteriaceae from the same samples and used hybrid sequencing (short- and long-reads) to create high- quality assemblies for comparison to the metagenomic data. To automate data processing, we developed an open- source software pipeline, ‘ResPipe’

Obituary: Alan Raybould

Professor Alan Raybould was born and raised in Wolverhampton, in the West Midlands, United Kingdom. He attained a First Class Degree in Botany from the University of Manchester, followed by his PhD in Population Genetics at the University of Birmingham in 1989, researching population genetics of Spartina anglica. Alan began his scientific career at the Institute of Terrestrial Ecology at Furzebrook, Dorset, which later became part of the United Kingdom Centre for Ecology and Hydrology. During this period (1990–2001), he progressed from a post-doctoral research position to becoming the lead scientist in molecular ecology, studying gene-flows from genetically-modified crops to related wild plant populations

Use of acoustic emission to identify novel candidate biomarkers for knee osteoarthritis (OA)

Our objective was to determine the efficacy and feasibility of a new approach for identifying candidate biomarkers for knee osteoarthritis (OA), based on selecting promising candidates from a range of high-frequency acoustic emission (AE) measurements generated during weight-bearing knee movement. Candidate AE biomarkers identified by this approach could then be validated in larger studies for use in future clinical trials and stratified medicine applications for this common health condition. A population cohort of participants with knee pain and a Kellgren-Lawrence (KL) score between 1-4 were recruited from local NHS primary and secondary care sites. Focusing on participants’ self-identified worse knee, and using our established movement protocol, sources of variation in AE measurement and associations of AE markers with other markers were explored. Using this approach we identified 4 initial candidate AE biomarkers, of which “number of hits” showed the best reproducibility, in terms of within-session, day to day, week to week, between-practitioner, and between-machine variation, at 2 different machine upper frequency settings. “Number of hits” was higher in knees with KL scores of 2 than in KL1, and also showed significant associations with pain in the contralateral knee, and with body weight. “Hits” occurred predominantly in 2 of 4 defined movement quadrants. The protocol was feasible and acceptable to all participants and professionals involved. This study demonstrates how AE measurement during simple sit-stand-sit movements can be used to generate novel candidate knee OA biomarkers. AE measurements probably reflect a composite of structural changes and joint loading factors. Refinement of the method and increasing understanding of factors contributing to AE will enable this approach to be used to generate further candidate biomarkers for validation and potential use in clinical trials

A systematic review of the relationship between subchondral bone features, pain and structural pathology in peripheral joint osteoarthritis

Introduction: Bone is an integral part of the osteoarthritis (OA) process. We conducted a systematic literature review in order to understand the relationship between non-conventional radiographic imaging of subchondral bone, pain, structural pathology and joint replacement in peripheral joint OA. Methods: A search of the Medline, EMBASE and Cochrane library databases was performed for original articles reporting association between non-conventional radiographic imaging-assessed subchondral bone pathologies and joint replacement, pain or structural progression in knee, hip, hand, ankle and foot OA. Each association was qualitatively characterised by a synthesis of the data from each analysis based upon study design, adequacy of covariate adjustment and quality scoring. Results: In total 2456 abstracts were screened and 139 papers were included (70 cross-sectional, 71 longitudinal analyses; 116 knee, 15 hip, six hand, two ankle and involved 113 MRI, eight DXA, four CT, eight scintigraphic and eight 2D shape analyses). BMLs, osteophytes and bone shape were independently associated with structural progression or joint replacement. BMLs and bone shape were independently associated with longitudinal change in pain and incident frequent knee pain respectively. Conclusion: Subchondral bone features have independent associations with structural progression, pain and joint replacement in peripheral OA in the hip and hand but especially in the knee. For peripheral OA sites other than the knee, there are fewer associations and independent associations of bone pathologies with these important OA outcomes which may reflect fewer studies; for example the foot and ankle were poorly studied. Subchondral OA bone appears to be a relevant therapeutic target. Systematic review: PROSPERO registration number: CRD 4201300500

Niche and local geography shape the pangenome of wastewater- and livestock-associated Enterobacteriaceae

Escherichia coli and other Enterobacteriaceae are diverse species with “open” pangenomes, where genes move intra- and interspecies via horizontal gene transfer. However, most analyses focus on clinical isolates. The pangenome dynamics of natural populations remain understudied, despite their suggested role as reservoirs for antimicrobial resistance (AMR) genes. Here, we analyze near-complete genomes for 827 Enterobacteriaceae (553 Escherichia and 274 non-Escherichia spp.) with 2292 circularized plasmids in total, collected from 19 locations (livestock farms and wastewater treatment works in the United Kingdom) within a 30-km radius at three time points over a year. We find different dynamics for chromosomal and plasmid-borne genes. Plasmids have a higher burden of AMR genes and insertion sequences, and AMR-gene-carrying plasmids show evidence of being under stronger selective pressure. Environmental niche and local geography both play a role in shaping plasmid dynamics. Our results highlight the importance of local strategies for controlling the spread of AMR