Penny Johnes

Attendees joined us from Defra, Welsh Government, Natural England, Natural Resources Wales, Environment Agency, the water industry, NFU, and multiple rivers trusts, catchment partnerships, local government and NGOs acting to protect freshwater quality in the UK. 🧪

The QUANTUM freshwaters programme is funded by the Natural Environment Research Council, UK and has been, since 2023, investigating the role of livestock (beef cattle, dairy cattle and sheep) as a driver of changing quality in UK rivers. This a particular problem in the north and west of the UK. The morning session provided our 50 attendees with an overview of the evidence emerging from each of our work packages, while the afternoon session focused on capturing their expert advice, as policy makers and environmental managers, on how we can better mitigate these impacts to reduce the flux of nutrients, organic and ecotoxin compounds as well as pathogens to UK rivers from livestock farming in the catchment.

Professor Charles Tyler, providing an overview of progress with our work on the ecotoxicological effects of contaminants in livestock excreta on the freshwater biota.

Barry Hankin and Hannah Champion from JBA consulting and Andy Binley from Lancaster University, provided attendees with a detailed briefing on the modelling we are undertaking to bring the evidence from QUANTUM together and make it accessible to end users.

Our team of researchers on the QUANTUM programme provided invaluable support in helping to get the event set up and off the ground, and also presented a suite of really useful posters providing detail on some of the analytical techniques we have developed and applied in this programme. The image shows Drs Ana Castro-Castellon (biogeochemistry) of the School of Geographical Sciences at the University of Bristol, Tolulope Lawrence (ecotoxin chemistry) from the University of Bath, Victoria Hussey from the School of Chemistry (organic geochemistry) at the University of Bristol, and Sydney Enns, our Specialist Biogeochemistry Research Technician who supported all of the field sampling and experimental work.

The @quantumfreshwaters.bsky.social team recently welcomed a wide range of Government, industry, farming and freshwater organisations to our Stakeholder event. Great discussions and exchange of ideas on livestock farming as a driver of changing quality in UK rivers and how to mitigate its impacts! 🧪

3 cows in a field

1/2 A workshop by QUANTUM led by @pennyjohnes.bsky.social is at @bristoluni.bsky.social
on 15 Jan to present findings from their research & capture ideas from their stakeholders.

They're working with scientists, farmers & regulators investigating how livestock farming affects water quality.

Figure 1 showing the locations of Tier 1 (in depth) and Tier 2 sites (spatially representative) sites included in this study. Inset A shows the location of the Tier 1 sites on the Conwy in North Wales, and B shows Tier 1 sites on the Hampshire Avon in Southern England.

Figure 2 shows the nutrient gradient captured in this study in the Tier 2 sites (a) for total and organic nitrogen concentrations and (b) for total and organic phosphorus concentrations. Sites are ordered from lowest to highest total nutrient concentration, which is represented by the total height of the bar.

Figure 3 shows nutrient limitation of sites and growth response ratios for inorganic and organic nutrients. (a) Inorganic nutrient response ratio is plotted for sites ordered by increasing TP concentration. Growth response ratios are then plotted for (b) inorganic nutrients and (c) organic N compounds against the site concentration of TN and (d) organic P compounds, against the site concentration of TP.

Great to see this latest @ukri.org DOMAINE Large Grant programme publication, from Ellie Mackay @ukceh.bsky.social which provides a key advance in our ability to predict of growth stimulation of river phytoplankton by organic nutrient enrichment at UK scale: onlinelibrary.wiley.com/doi/10.1111/... 🧪

Beautiful demoiselle damselfly, watching us as we ran our clay stream mesococm experiment, July 2025.

James MacDonald, taking sensor readings for temperature and light in our chalk stream mesocosm experiment.

Charlotte Briddon and Sydney Enns, sampling the isotope treatments in one of three mesocosm experiments we ran in summer 2025. We are a fun and friendly team with loads of experience and enthusiasm. Great working environment!

James setting up slides for biofilm cultivation prior to our chalk stream isotope dosing experiment.

Seeking an experienced postdoc in freshwater environmental genetics to join our exciting @ercrefresh.bsky.social @erc.europa.eu @ukri.org team to investigate environment x gene interactions in freshwater biotic responses to environmental stressors www.jobs.ac.uk/job/DPK766/s... @mgenner.bsky.social

Come and join our team!

Helping the team with mesocosm dosing experiments this summer.

Native aquatic snails added to mesocosms to investigate the uptake of DOM.

Learning about the experimental setup from James McDonald.

Excited to start my PhD at @bristoluni.bsky.social as part of the @ercrefresh.bsky.social project under Penny Johnes, Dan Read (UKCEH) and Martin Genner!

I'll be exploring how key microorganisms utilise and transform dissolved organic matter. Looking forward to starting with the team next week!

Welcome to the team Matt, and thank you for all the help with our field experiments over the summer!

James McDonald snd Matt McCormack extracting mesocosms from frames

Native aquatic snails collected 4 days after introduction to jars with 15N13C labelled biofilms and bryophytes.

Matt and Boyi transferring heated mesocosms to the bank for eDNA and eRNA extraction, led by Martin Genner

Leave no trace! Site returned to its original state after decommissioning. With many thanks to Bannau Brycheiniog National Park Authority for permission to work on the land.

And that's the final @erc.europa.eu @ercrefresh.bsky.social stream isotope experiment of our 2025 field season complete. With many thanks to @bristoluni.bsky.social PhD students Matt McCormack and Boyi Li for their help with eDNA sampling and completing site decommissioning before the rain arrived 🧪

Couldn't afford to include them with a capped budget of £2m. This molecular scale work is very expensive! Next project....

Ayrshire X cattle in Scotland with direct access to a headwater stream.

Cattle having direct access to streams causes significant increase in water pollution risk.

Dairy Holstein Friesian herd in Wales, outdoor grazed.

Sheep typically have direct access to watercourses too. They too can markedly increase pollution in headwater streams.

All fieldwork is now complete on our ukri.org @quantumfreshwaters.bsky.social project including sampling in 60 UK livestock farming headwater streams. We now focus on sample and data analyses, while we build models to test the likely efficacy of mitigation efforts to reduce impacts on UK rivers 🧪

Do pass this on to any budding environmental and analytical chemists! Great opportunity to join this exciting programme!

Male Beautiful Demoiselle damselfly, abundant at our clay stream site in SW England.

Female Beautiful Demoiselle damselfly at our site.

These damselflies frequently landed on us and our equipment as we worked.

We found several of these small, native freshwater limpets on our biofilm slides when we extracted them. Ancylus fluvialitis.

That's a wrap on our @erc.europa.eu @ukri.org @ercrefresh.bsky.social programme 2nd expt.. A very different environment than the chalk stream in our 1st expt. but nonetheless with wonderful biota: Beautiful Demoiselle damselflies fluttering around us, and freshwater limpets grazing our biofilms! 🧪

Charlotte Briddon and Sydney Enns working on the ambient treatment mesocosms in our clay stream experiment.

Sydney Enns wearing her chest waders. These neoprene waders are warm and keep us dry (mostly, as long as we avoid barbed wire punctures) but we do get buoyant feet when we sit down!

Kind support from two volunteers: Nina Aspey, and Matt McCormack, Durham University Biological Sciences graduate who is joining us in the autumn as our first REFRESH PhD student.

A successful day at our peat stream site today with James McDonald, setting up our biofilm cultivation slides so that they are ready for this final experiment in August. The sheep hurdles are to keep the sheep grazing this common out of the experiment!

Our @ukri.org funded @erc.europa.eu REFRESH programme is going well! Chalk stream isotope dosing expt. complete, clay expt. nearly complete with help from our first PhD student, @durham-university.bsky.social graduate Matt McCormack. Peat expt. set-up now underway @bannaubrycheiniog.bsky.social 🧪🐟🌿🐌

Farming Today - 22/07/2025: water pollution, farmers' wellbeing - BBC Sounds Water pollution, farmers' wellbeing.

Spoke on BBC Radio 4 Farming Today this morning on the implications of the Cunliffe Report for UK farmers and freshwaters, explaining some of the key findings from our @ukri.org funded QUANTUM programme on livestock impacts on www.bbc.co.uk/sounds/play/... 🧪

An algal bloom on a nutrient enriched lake encroaches into the Nymphaea alba and Chara hispida beds, causing plant dieback. Your work will develop a novel, targeted analytical method to allow us to rapidly screen samples to determine the molecular composition of the dissolved organic nutrients in these and other waters. These provide a critically important but overlooked nutrient resource driving ecosystem damage and biodiversity decline in waterbodies. We currently lack a unified technique that can rapidly screen samples in a targeted manner. You'll likely be highly motivated, enjoy both field and laboratory work, and be a good analytical chemist with attention to detail who is keen to make your mark through novel method development. Give Ian a ring or send him an e.mail (ian.d.bull@bristol.ac.uk), or contact me here or via my e.mail penny.johnes@bristol.ac.uk. We have a large team on the ERC REFRESH programme that you will be joining, along with two other PhD students due to start at the same time. Great team and learning opportunities.

‪Great opportunity: full @ukri.org funded PhD Studentship with 4 years fees, stipend (£19237 pa) and full Research Training Support Grant, working with Prof Ian Bull, Director of the National Environmental Isotope Facility and my
@ercrefresh.bsky.social team! Starts 10/2025 shorturl.at/AJREj 🧪

Great opportunity to win a full @ukri.org funded PhD Studentship with 4 years fees, stipend (£19237 pa) and full Research Training Support Grant, working with Prof Ian Bull, Director of the National Environmental Isotope Facility and my @ercrefresh.bsky.social team! Starts 10/2025 shorturl.at/AJREj

Challenging but fun @erc.europa.eu and @ukri.org science now underway! We next add snails to the jars at 96 h, and return to collect them with remaining biofilms and bryophytes at 192 h. Looking forward to @mgenner.bsky.social joining us at 192 h to sample for our omics work. Roles advertised soon!

This week I helped setting up the mesocosm experiment for the @ercrefresh.bsky.social programme lead by @pennyjohnes.bsky.social with @jameslmcdonald.bsky.social and Charly Briddon. The landscape was a dream.

Our team of 3 PDRAs, 3 research techs and 3 PhD students (5 still tba) will work with me, @mgenner.bsky.social & Mark Beaumont of @bristoluni.bsky.social Biological Sciences, and OGU (Ian Bull), @ukceh.bsky.social Dan Read, Ellie Mackay, Daren Gooddy, @bangoruniversity.bsky.social (Davey Jones).

Thanks. We've recruited two excellent freshwater scientists and are underway now with the first isotope experiments. We'll be recruiting for an experienced omics specialist at postdoc level, and a specialist technician to support them in the autumn. Please spread the word!

Lowland sheep impacts on streams sampled in SW England in our @ukri.org QUANTUM programme, with help from @a.castrocastellon.bsky.social

Beef cattle typically (like sheep) have direct access to watercourses where there is defecation in the channel and poaching of stream bank sediments, contributing to a high risk of contaminant transfer to streams. We are testing samples to determine their ecotoxin, pathogen, nutrient and organic matter composition.

In around 50% of dairy farmed catchments, outdoor-grazed livestock are able to directly access streams. This leads to the same impacts as in beef cattle systems. In the other 50%, where animals are housed, water is abstracted to provide the cows with the capacity to produce milk. The average production rate is 22 litres per cow per day, with some high yielding cows producting much more. If a farmer has a herd of 500 cows, this can amount to over 11000 litres of water per farm, exported from the catchment every day in the form of milk or milk products. As a result where there are large commercial herds kept indoors streams often run bone dry or at very low flows in the summer months, reducing their dilution capacity for contaminants, increasing environmental exposure rates for stream biota, and making the stream ecosystem much more susceptible to climate warming effects.

We've now completed our QUANTUM sampling at 33/60 sites, in SW of England, W England and Wales. Next stop N England and Scotland! By focusing on streams draining sheep, beef and dairy farmland, we are building a national picture of their impacts on UK river water quality to better inform policy.🧪

An idyllic scene, but hidden within is ecosystem damage as cattle urine and dung are directly voided into the stream or onto the stream margins.

Some of the culprits

Who did that?

A contaminated site. Water flows from her to the river and out to coastal bathing waters. Contaminants include ecotoxins, pathogens, organic matter and nutrients.

When livestock have direct access to watercourses, the risk of ecotoxin, pathogen, organic matter and nutrient pollution increases to 100%. Our
@ukri.org QUANTUM programme sampling found some culprits today..... @acastrocastellon.bsky.social @victoriahussey.bsky.social 🧪🐄🐂

Beef cattle, and a very aggressive bull guarding his herd.

Dairy cattle in the Cleddau catchment

Start of Day 3, in the headquarters of the Tywi catchment before heading over to the Usk. Days 1 and 2 sampled the Cleddau (W and E), Nyfer, Taf, Teifi and Aeron catchments!

A sprightly cow during our sampling trip to the W Cleddau. Shout out to the West Wales Nutrient Management Partnership who put us in touch with the farmers, and the farmer who gave us permission to visit their farms.

Our @ukri.org QUANTUM national sampling programme is now well underway. Thanks to @acastrocastellon.bsky.social for help with the SW England sites, Sydney Enns and @victoriahussey.bsky.social for prepping the kit, and my husband who helped with the Welsh sites - great cow poo sampling skills! 🧪🐄🐑🐂

I would say we also need action to protect the native biota and food chains in freshwater and marine ecosystems that are distorted, diminished or replaced by these blooms. It's not just about protecting environmental goods and services for 'us' but protecting the environment on its own merits. 🧪

Harmful algal blooms, fueled by nutrient pollution and rising temperatures, threaten marine life and human health by releasing toxins into water and seafood.

We need #ClimateAction and stronger efforts to cut nitrogen and phosphorus pollution.

Roger Keel, ready to repair the fencing in our enclosure prior to letting the extensive beef cattle back in to graze off the lush grass on our slurry amended plots. @acastrocastellon.bsky.social, @jameslmcdonald.bsky.social, @bristoluni.bsky.social

Paul and Roger Keel in conversation with Catchment Sensitive Farming officers at our autumn stakeholder event.

Paul in conversation with Ed Fredenham of Bristol Water, during our autumn stakeholder event.

As we finish our NERC QUANTUM field experiments and move on to upscaling and modelling work at national scale, we'd like to thank the residents of Rickford and our hugely helpful farmers, Paul and Roger Keel for their support. We'll return in the autumn to tell you what we've found!

Aviation Engineering PhD students from University of Bristol, flying a drone over our field site to capture aerial images of the impacts of slurry amendments on vegetation growth. Very grateful to them, as we interrupted them at their summer BBQ and drone festival. Good spot by our new research team member, @jameslmcdonald.bsky.social‬

Drone at the field site, set up to capture aerial and multi-spectral data.

Drone flying over our field site at Rickford, N Somerset. @acastrocastellon.bsky.social, @jameslmcdonald.bsky.social‬

Kilian Meier, 2nd year PhD student in the @bristoluni.sky.social Aviation Engineering group, flying a drone over our field site at Rickford, N Somerset.

Last day in the field, returning our NERC QUANTUM field kit to the @bristoluni.bsky.social Fenswood field store where we bumped into our Aviation Engineering colleagues flying drones. They kindly agreed to fly over our field site producing aerial images for our future presentations. Great teamwork!🧪

Yes indeed! Great work from the team and, if I may say so, brave work from the PI who had to stand in the outer field and hold the theodolite while the cattle licked her coat, while Prof Andy Binley surveyed in the site - 1st principle for PIs: #neveraskyourteamtodosomethingyouwouldn'tdoyourself 🧪🐮

Professor Charles Tyler, University of Exeter, who leads the QUANTUM programme ecotoxicology work, holding a sample of three-spined stickleback following our field ecotoxin exposure experiments.

The University of Exeter Biosciences field team, led by Dr Anke Lange, processing samples from the QUANTUM field ecotoxicology experiment

Dr Simona Frustaci, another of our QUANTUM programme PDRAs, with a sample of freshwater shrimp, Gammarus pulex, following the QUANTUM field ecotoxin exposure experiments.

Sydney Enns, who with @jameslmcdonald.bsky.social‬, @acastrocastellon.bsky.social‬ and @pennyjohnes@bsky.social, spent the day decommissioning the site, recovering our key for cleaning and prep for other projects, and tidying up the site ready for the cattle to return to the site next week. We also spent the afternoon collecting a final set of soil samples from our control, 40m and 10m slurry amendment plots, to explore downslope nutrient trends (from hillslope to stream) following a year of slurry amendments.

Final day of sampling today for the @bristoluni.bsky.social
team at our NERC QUANTUM field site, and the
@exeter.ac.uk QUANTUM team completing their field ecotoxin exposure experiments. This was a fantastic field site for the project. Many thanks to the farmers and villagers for their support.