Invertebrate biodiversity is improving in England’s rivers, long-term trends show

Rivers across England have seen a significant improvement in river invertebrate biodiversity since 1989, shows a study led by UK Centre for Ecology & Hydrology (UKCEH) researchers.

The study, which involved one of the largest and most wide-ranging analyses of long-term monitoring data in the world – spanning over 30 years, found improvements in invertebrate biodiversity across all regions and river types in England.

This improvement is all the more surprising given English rivers are amongst the most highly exposed to wastewater and other pressures in Europe. The recent State of Nature report shows that the overall abundance of species in Great Britain has declined on average by 19%. For terrestrial invertebrates the decline is unequivocal, but this is not the case for freshwater invertebrates.

Published in Science of the Total Environment, this latest analysis adds weight to a growing body of evidence showing that freshwater invertebrate species have been moving towards recovery across England and Europe since the 1990s.

The study analysed data from up to 223,300 routinely collected freshwater records from the Environment Agency across England between 1989 and 2018. The researchers looked at the presence of invertebrate families like dragonflies, snails, mayflies, shrimp and worms which respond to changes in water quality. They examined how the presence and numbers of each family changed over time at each location.

Nationally, the long-term trend is positive. The average number of families of freshwater invertebrates found at each site increased from 15 to 25 between 1989 and 2018. Overall, this is an average 66% increase in the number of invertebrate species observed in England’s rivers over the past 30 years. However, this rate of improvement began to slow for some groups from 2003 onwards.

These trends are seen across every river type, from upland to lowland, from rural to urban, and in areas with low to high levels of arable farming. Rivers with higher exposure to wastewater or pesticides were less rich in invertebrates, yet these sites also showed improvement. Given the universality of this improvement and its timing, which coincide with declines in some key chemical pollutants, these trends across England’s rivers may be linked.

Crucially, the data shows that families that are particularly sensitive to river pollution, like mayflies, stoneflies and caddisflies, are recovering most strongly of all. The diversity of these species improved by 300% overall, rising from an average of 3 families recorded at each site in 1989 to 10 families in 2018. This recovery continued until 2003 when the rate of biodiversity improvement for some other families started to level off.

While there is still room for improvements and there are many local issues still to tackle, at the national scale England’s rivers now provide far better habitats for invertebrates than they did 30 years ago. To an extent where, for some invertebrate species, England’s rivers have reached the target ecological standard for populations to thrive.

Lead author Professor Andrew Johnson, Principal Scientific Officer at UKCEH, said: “Long-term monitoring has shown us a dramatic improvement in the biodiversity of freshwater invertebrates over the past 30 years across all river types at the national scale. Similar trends are also observed across Europe, and in the decades during which changes in legislation around water treatments and restoration projects have been introduced driven by EU policies. This suggests that water quality improvements have been effective at allowing freshwater biodiversity to recover. Since these trends are also observed across Europe, it suggests that water quality improvements, consistent with changes in legislation around wastewater treatments and associated restoration projects, have been effective at improving freshwater biodiversity. The implication is that given good legislation, resources and regulation, we can reverse biodiversity decline.

“We now need to understand more about the role chemical changes or conservation measures have had in achieving this recovery in England’s freshwater invertebrates, and to what degree current levels of pollution affect wildlife in relation to other issues.”

The analysis accounted for geographical factors like latitude, altitude and the slope of the waterway, alongside wastewater exposure and the type of land each river flowed through. It also considered the effect of invasive species, finding the increase in the distribution of such species across the sample sites was only modest and could not on its own account for the overall trend in biodiversity.

The study included researchers from UKCEH and Brunel University London. It was funded by the National Environment Research Council, part of UK Research and Innovation.

Benchtop NMR spectroscopy can accurately analyse pyrolysis oils

A team of researchers at Aston University has demonstrated that benchtop spectrometers are capable of analysing pyrolysis bio-oils just as well as far more expensive, high-field spectrometers.

Bio-oils resulting from the intense heating (pyrolysis) of industrial or agricultural by-products, are increasingly seen as potential alternatives to fossil fuels. But the stability and consequent treatment of these bio-oils depends entirely on their composition; and since they are often mixtures of many dozens, or hundreds, of different compounds, analysing such complex mixtures is not simple – or cheap.

Dr Robert Evans, Senior Lecturer in Physical Chemistry at Aston University, explains: “The composition of any pyrolysis bio-oil is absolutely key to future use. For example if there are oxygen-containing chemicals in the oil, that will make the oil more corrosive and it will be more unstable. So in particular we need to know if carbonyl groups are present – where oxygen and carbon atoms are bonded together – as these can have a major impact.”

A leading method of analysis is high-field nuclear magnetic resonance (NMR) spectroscopy, which gives a detailed breakdown of the identity and concentration of chemical species present in any sample. However these large high-field NMR spectrometry machines cost in the range of £600,000-£10million and require a supply of expensive cryogens and solvents, so are generally only found in the very biggest research facilities.

The team at Aston, led by Dr Evans, set out to see if ‘low-field’, or benchtop, NMR spectrometers, could analyse pyrolysis oils well enough to produce the necessary detailed information. Benchtop NMR spectrometers use permanent magnets, which don’t require cryogenic cooling, so cost much less to purchase and maintain. However, using lower strength magnets comes at the cost of lower sensitivity and poorer resolution. While they can find some use as research instruments, they are also commonly found in teaching laboratories.

The study, carried out with collaborators at the University of Tennessee, tested pyrolysis oils produced from a number of different plants, and compared the results from benchtop spectrometers to both high-field spectrometers and other methods of analysis. They found that the benchtop machine estimates compared favourably with titration analysis for overall carbonyl content, as well as matching high-field spectrometry for the specific identification of carbonyl groups such as ketones, aldehydes and quinones.

Dr Evans said: “Despite the known limitations of benchtop spectrometers, a very similar quality of NMR data could be obtained for these samples, enough to accurately estimate concentrations of different classes of carbonyl-containing species. Using benchtop spectrometers will make NMR analysis of pyrolysis oils much simpler, cheaper, and more accessible to a wider range of different users.”

Quantitative Low-Field 19F NMR Analysis of Carbonyl Groups in Pyrolysis Oils is published online today in ChemSusChem, a journal of Chemistry Europe.

Cautious welcome to UK’s new Biomass Strategy

A group of bioenergy experts have welcomed the Government’s new UK Biomass Strategy, but say urgent action is now vital to shape its ambitions into deliverable policies.

Researchers at the Supergen Bioenergy Hub – led by Aston University – worked closely with government departments to provide scientific evidence to inform the strategy, which outlines the role biomass will play in supporting the UK’s transition to net zero and how this will be achieved.

Professor Patricia Thornley, who leads the Hub, says: “This is a comprehensive and considered biomass strategy that, rightly, places sustainability at the heart of UK bioenergy development. The challenge is now to produce actions that can deliver the sustainable system of biomass required to achieve net zero.”

Sustainability is a major theme within the new strategy. It includes a review of how existing sustainability policies could be improved, as well as a commitment to developing a cross-sectoral sustainability framework (subject to consultation) to ensure sustainability across the many different applications of biomass. This follows previous work led by Dr Mirjam Rӧder, Systems Topic Group Lead in the Supergen Bioenergy Hub, calling for harmonised sustainability standards across different biomass applications, which is referenced in the strategy.

Dr Rӧder says: “We need rigorous approaches to sustainability governance that go beyond emissions. Considering wider environmental, social and economic trade-offs is essential for true sustainability and building trust in bioenergy projects.”

The strategy considers the amount of biomass resource that might be available to the UK in the future, highlighting the importance of both imported and domestically produced biomass resources. Professor Thornley comments: “It is important that the strategy recognises the potential of imported as well as indigenous biomass in achieving global greenhouse gas reductions. Sustainable systems should grow, convert and use biomass in the locations where they can deliver most impact, ensuring we take account of all supply chain emissions. We shouldn’t shy away from imports where the source is sustainable and the overall system makes environmental, economic and social sense.”

The strategy also considers how biomass should be prioritised across a variety of applications to best support the transition to net zero. Biomass applications ranging from transport fuels and hydrogen to domestic and industrial heating are recognised as important, but in the medium to long term the focus is on integration of bioenergy with carbon capture and storage (BECCS).

BECCS is an emerging technology where the CO2 that may be released during the production and use of electricity, fuels or products derived from biomass is captured and stored, potentially resulting in negative emissions.

Professor Thornley comments: “The priority use framework outlined in the Biomass Strategy makes eminent sense. The UK (and the global energy system) needs carbon dioxide removals to deliver net zero. BECCS has an absolutely key role to play, as reflected in the strategy. Again, while this is encouraging to see, we must not underestimate the challenges of moving towards such a radically different system at scale.”

“Relying on future BECCS deployment alone to counterbalance the current excess of greenhouse gas emissions would not enable the full potential and benefits of BECCS. BECCS should be deployed alongside measures to transition away from the use of fossil fuels, not instead of them,” adds Dr Joanna Sparks, Biomass Policy Fellow at the Supergen Bioenergy Hub, who engaged closely with government departments as they developed the strategy.

Dr Sparks led an extensive policy engagement and knowledge transfer process to ensure that those developing the strategy had full access to the breadth and depth of UK scientific and engineering academic expertise, ensuring a robust, independent scientific base.

Professor Thornley believes continued engagement between policymakers, academics and the wider sector is vital in achieving the next steps in the delivery of the Government’s strategy. She says: “The key to successful long-term results is a close partnership between academia, industry and policy stakeholders so that we can anticipate problems and plan the pathways to success.”

NHS geospatial app saves vital staff time

NHS Trusts could help staff plan their journeys more efficiently and cut their impact on the climate with software that can help district nurses and health visitors plan their journeys more efficiently.

Data scientists from NHS England’s Digital Analytics & Research Team and engineers from Google Health collaborated to develop a web app that can optimise routes between locations. This can help to reduce the amount of fuel used when making health visits or by ambulances that have a series of patient drop offs to do. As well as saving money and cutting carbon emissions, it can also mean health workers spend less time travelling between visits, giving them more time to spend with patients.

It is due to be presented at the first ever Health and Care Analytics Conference, which is taking place in Birmingham on 11-12 July.

“District nurses can be visiting multiple patients in their homes each day, so we wanted to find a way for them to plan the most efficient route to get to the patients,” said Paul Carroll, senior data scientist at NHS England’s Digital Analytics Research Team, who led the project.

“If they have 10 appointments in a day, there could be 3.6 million different routes they could take. If there are 12 addresses to visit, that becomes 479 million permutations. These are difficult problems to solve and we wanted to be able to do it in a way that could be done an average laptop computer.”

Currently, many NHS trusts rely on third party companies to provide routing information.

Mr Carroll and his team, who were working as part of programming community called NHS-pycom, developed the code in an open-source app framework called Streamlit so that analysts at NHS trusts could adapt it to their requirements. This could help to overcome potential data privacy issues as the patient information would not have to be sent to a third party or uploaded to a server.

In the case of district nurses, they could use the app to plot routes between up to 12 addresses and display them on a map, taking into account the distance between each one, driving times at peak and off-peak hours, walking time and cycling time.

“The idea is they can spend less time travelling and more time with patients,” said Mr Carroll.

The app has two additional functions which were developed in response to unmet needs identified by NHS Trusts. One suggests the shortest route that staff and patients might be able to take to reach a hospital or other health service. This could be used to help reduce the climate emissions as they travel to work or to help patients find which service is closest to them. Although this initially used driving and walking data, Mr Carroll said it could be expanded in the future to include public transport and cycle routes.

The second tool was designed to show the best location for services such as a vaccination centre or mobile blood test unit to ensure they can cover as much of the population in an area as possible. This took into account travel time and local authority population data and was a simplified version of something that many retailers already use to find the best place to locate a new store that is accessible by as many people as possible and away from competitors.

“Geospatial needs within the NHS are everywhere, from ambulance patient drop-offs to where to site a new GP practice within your community,” said Mr Carroll.

New glass sensors could make commercial nuclear fusion viable

A new generation of durable sensors capable of monitoring commercial nuclear fusion reactors in real time is being developed by UK researchers.

The team, led by Bangor University in partnership with Sheffield Hallam University, plan to identify whether glass sensors developed in 1960s could function in the extreme conditions of a nuclear fusion reaction. If not, the researchers will design and develop new glass sensors.

In December 2022, researchers in the United States for the first time generated more energy from a nuclear fusion reaction than was put in, opening up the possibility that the technology could be both commercially viable, and able to supply abundant, clean energy. But one of the requirements to move from experimental reactions to commercial power generation is reliable monitoring. This means overcoming the extreme conditions created in a fusion reaction: temperatures of 150-200 million degrees Centigrade and highly energetic fast-moving neutrons.

One way of monitoring a fusion reaction is to count the number of neutrons it gives off using scintillators – blocks of material in which a sparkle of light is created each time it is hit by a neutron. By counting the flashes of light, it’s possible to calculate the number of neutrons and the amount of energy being produced – helping to ensure everything is working as intended.

However, existing scintillators are mostly made from either crystal or polymer, which are either difficult to make and limited in size and shape, or lack the durability to withstand the more extreme conditions created by fusion reactions. The sensors currently used to calculate the energy output from fusion reactions tend to be cumbersome and awkward, and do not allow real-time and long term monitoring of the fusion process. For commercial nuclear fusion reactors to be run safely and efficiently, sensors will need to work reliably for years.

Dr Michael Rushton from Bangor University’s Nuclear Futures Institute is leading the new project. He said: “Glass has intrinsic radiation tolerance, so can survive well in very harsh conditions. It also has the advantage that it can be made in very different shapes, from fibres to plates which means sensors can be made for a range of situations within a reactor. And it’s fairly low cost to manufacture. We also hope to be able to ‘tune’ the sensors to work with different types of radioactive particle, so they may also be used for other applications, such as airport or medical scanners.”

Glass sensors able to register radioactive particles were first developed in the 1960s, but they only work if particles are travelling relatively slowly. The Bangor University team is initially seeing if particles emanating from a fusion reaction could be slowed down sufficiently to allow these sensors to work based on their existing composition. If this isn’t possible, then they will use machine learning approaches to identify new configurations of glass that could be effective in the conditions found within nuclear fusion. The new sensor designs will then by manufactured by their colleagues at Sheffield Hallam University.

Professor Paul Bingham from Sheffield Hallam University said: “This research will develop an entirely new range of glass-based sensors for some of the most extreme environments on Earth. This means it could not only help accelerate safe development and deployment of fusion energy technologies, but also have wide-ranging applications in other fields in the future.”

The two-year research project is funded through UK Research and Innovation’s Engineering and Physical Sciences Research Council. It involves Bangor and Sheffield Hallam Universities, the University of Birmingham, the ISIS Neutron and Muon Source at the Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory as well as a number of commercial partners.

Loch Leven monitoring data now available through new online portal

Photo credit: Linda May, August 2022

An online portal to help local people, policy-makers and regulators understand the ecology of Loch Leven better is being launched today by the UK Centre for Ecology & Hydrology (UKCEH).

Situated in Perth and Kinross, Loch Leven is the largest shallow loch in lowland Scotland and is of international importance as a brown trout fishery, wildlife haven and recreational site.

The Loch Leven portal provides current and historical information about the loch, together with an array of useful resources for schools.

By sharing high quality data on the past and current condition of the loch, the portal will ensure that decisions on how to protect, maintain and manage the loch for the benefit of people and nature are based on strong evidence. These decisions include how to reduce toxic algal blooms.

Loch Leven hosts one of the longest running lake monitoring programmes in the world and the data being made available through the portal are extensive. UKCEH and its predecessors have been sampling Loch Leven every two weeks, all year round, since 1968. Also, every ten years since 1985, UKCEH has carried out detailed weekly assessments, over a 12-month period of the amount of nutrients entering the loch from its catchment. The next survey is due in 2025.

Excess amounts of nutrients – such as nitrogen and phosphorus – can lead to a rapid accumulation (bloom) of blue-green algae (cyanobacteria) in all types of lakes, and this has been a well-documented problem at Loch Leven since the 1970s. Blue-green algae have a serious detrimental effect on water quality, not least because some species produce toxins that can cause health problems if touched or swallowed. These include skin rashes, nausea and vomiting, and diarrhoea. These toxins can be particularly dangerous to dogs, if ingested.

The nutrients that fuel algal growth come from a variety of sources. These include agricultural runoff, industrial discharges, and effluent from septic tanks and other types of wastewater treatment systems. In the 1980s and 1990s, massive outbreaks of blue-green algae at Loch Leven were tackled by working with farmers, Scottish Water and the local planning department to reduce the levels of nutrients entering the loch. This improved water quality.

However, additional steps are likely to be needed to tackle the current increase in blue-green algae. This is because climate change is making the loch more sensitive to these nutrients. For example, higher temperatures are causing phosphorus that has been stored in the loch sediments over many years to be recycled back into the water. This increases nutrient levels and encourages the algae to grow. A recent report published by the Centre of Expertise for Waters (CREW) shows that this problem is occurring across Scotland and is not specific to Loch Leven.

Dr Linda May, a freshwater ecologist at UKCEH, who leads the Loch Leven long-term monitoring programme, said: “Blue-green algal growth can be caused by a variety of factors, so it is often difficult to find the right solution to the problem. We hope that, by sharing the Loch Leven data through this portal, we can provide high-quality data to ensure that well-informed decisions are made about measures to reduce these algal blooms.”

The portal will provide an overview of the changing environmental conditions at Loch Leven, with the full data sets available on request for those who require more detail.

As well as being important for the management of the loch at a local level, the data collected at Loch Leven are of national and international significance, according to Dr May.

“Loch Leven is one of a small number of lakes around the world that have this level of detailed, long-term monitoring in place,” she said. “Analysing and comparing the data that we are gathering helps us understand how lake ecosystems are responding to change, given the multiple environmental, climatic and human pressures they face. This knowledge can then inform evidence-based decisions on the restoration and sustainable management of similar lakes worldwide.”

UKCEH collect data on Loch Leven through the UK-SCAPE programme, a National Capability initiative funded by the Natural Environment Research Council, part of UK Research and Innovation. The Loch Leven portal was funded by the William Grant Foundation, which supports numerous environmental and community projects across Scotland.

Neighbourly cooperation can ensure your genes survive, new research finds

Image Alt Text: Photo of Derbyshire wood ant field site (Credit: Sam Ellis)

Cooperating with your neighbours, especially if they are distant relatives, can be an effective evolutionary strategy, new research has found.

The study found that social animals that work closely with their nearest neighbours to repel other groups can maximise the chance of their genes surviving, because those neighbours are likely to carry the same genes too.

The team of UK and US scientists have developed a mathematical model to explain unusual behaviour identified in some ants and primates. Although most species are highly competitive and fight with neighbouring groups, some will work with their neighbours and actively share resources.

Dr Elva Robinson from the University of York has seen this phenomenon amongst groups of wood ant nests in Derbyshire, which she has been studying for the last decade.

“Wood ants are known to be highly aggressive, spraying acid if ants from other nests encroach on their territory,” said Dr Robinson. “Yet sometimes multiple nests live peacefully side by side in the same ‘colony’, fighting off outsider ants that come near. The colonies I study have taken this one step further in that they also share food between nests. Some nests gather no food themselves, but rely purely on food supplied by workers from other nests.”

Most primates are aggressively territorial, and only bonobos and humans have been known to share resources in this way. Bonobos will meet neighbouring groups at the boundaries of their territory to exchange high value food such as meat.

Dr Robinson worked with colleagues Dr António Rodrigues from Yale University and Dr Jessica Barker from Aarhus University and the University of Alaska Anchorage to try and explain how this level of cooperation could come about and what benefits it might offer to those involved.

They developed the following hypothesis. Firstly, plentiful food means that the group gets bigger but also reduces conflict between its members. When offspring move away to establish satellite groups they don’t move far, in order to remain close to food sources. Kinship and plentiful resources results in little conflict between these different, but related, groups, and makes it in their interest to prevent new groups getting settled nearby. Finally sharing of resources ensures that all the cooperating groups thrive.

To test this hypothesis, Dr Rodrigues created a model that can mathematically quantify the evolutionary consequences of different levels of cooperation. The model allows the researchers to change a number of variables – such as how far offspring move from the parent group – to see how this affects the outcome.

Dr Rodrigues said: “It’s not possible to manipulate these variables in the field, so the only way to see if the theory makes sense is to create this kind of model. Using the model, we can also see how groups could benefit from this kind of cooperation, particularly in terms of ensuring the survival of their genes.”

The team found that when offspring stayed close to the main group, it was advantageous to all involved to cooperate and prevent others entering the area. Even if fighting off an aggressor in collaboration with your neighbours resulted in all your own group dying, your genes would still have a higher chance of continuing through your more distant relatives.

Dr Barker studies human behaviour, but warns against reading too much from the study into levels of cooperation and aggression between human groups. “Our model looks at the evolutionary benefits of behaviour over a long timescale, rather than the decisions we make over shorter timescales to unconsciously maximise such evolutionary advantages,” she said.

“Where the model might have relevance is in trading between early humans, where groups might more readily trade with nearby groups that were related, rather than those where there was no familial connection. That probably would have provided an evolutionary advantage to those families, and still seems likely to us today.”

The research is published in Philosophical Transactions of the Royal Society B.

Wildlife recording is good for people, as well as for science

Photo credit: Michael Pocock

Science is not the only beneficiary of nature-based ‘citizen science’ projects – taking part also boosts the wellbeing of participants and their connection to nature, according to research published today in People and Nature journal.

The study, ‘Nature Up Close and Personal: A Wellbeing Experiment’, is the first large-scale study to measure the wellbeing benefits to the volunteers taking part in citizen science projects – such as the wildlife recording activities providing data that are vital to assess environmental change. It was conducted during the pandemic restrictions of 2020 by the UK Centre for Ecology & Hydrology (UKCEH), the University of Derby and the British Science Association.

Five hundred volunteers from across the UK were randomly assigned to carry out a 10-minute nature-based activity at least five times over eight days: a pollinating insects survey, a butterfly survey, simply spending time in nature and writing down three good things they noticed, or a combination of both. The groups were surveyed both before and after taking part to assess differences in their connection to nature, wellbeing and pro-nature behaviour.

The researchers found that all volunteers showed increased scores in wellbeing and feeling connected to nature after completing their activities. Participants’ comments included:

“It gave me permission to slow down”; “It made me more aware of nature in all aspects of the environment”, and “It reminded me that small things can make a big difference to my mood”.

In addition, those writing down three good things they noticed, either alone or when combined nature recording activities, reported they were more likely to adopt pro-nature behaviours beyond their involvement in the project, such as planting more pollinator-friendly plants in their gardens, or creating shelters for wildlife, showing that taking part in citizen science has even more benefits for nature.

Dr Michael Pocock, ecologist and academic lead for public engagement with research at UKCEH, said: “Being in and around nature is good for our wellbeing, and we’ve shown that focused, active engagement with nature is just as important – whether that is ‘mindful moments’ in nature or taking part in citizen science.”

He adds: “This has been a valuable exercise for us in exploring how we can make citizen science even better. We now know that if we design future projects with additional nature-noticing activities, for example, we can enhance people’s own connection to nature, while still collecting valuable data.”

Co-author Professor Miles Richardson, who leads the Nature Connectedness Research Group at the University of Derby, said: “People connect with nature in different ways, so it’s great to see nature-based citizen science can provide another form of active engagement that can strengthen the human-nature relationship. When combined with noticing the positive emotions nature can bring, citizen science and help unite both human and nature’s wellbeing.”

There are many nature-based citizen science projects run by different organisations across the year. UKCEH welcomes support from anyone interested in volunteering to get involved with recording wildlife via the iRecord website, and free-to-use apps for butterflies, and the UK Pollinator Monitoring Scheme. Records from these citizen science projects are used in vital scientific research to understand changes in our wildlife.

UK’s Overseas Territories at risk from wide range of invasive species

A new study has for the first time predicted which invasive species could pose a future threat to the UK’s ecologically unique Overseas Territories.

The 14 Territories – many of them small, remote islands such as St Helena and Pitcairn – are home to species found nowhere else in the world. This makes them extremely vulnerable to biological invasions – in the oceans or on land – which could lead to the extinction of these endemic species or irrevocably change their unique ecosystems.

Researchers at the UK Centre for Ecology & Hydrology (UKCEH) and Durham University, working in partnership with communities on the Overseas Territories, assessed thousands of potential invasive non-native species, to predict which are most likely to arrive and impact these environments within the next 10 years.

The resulting research, published in the journal ‘Conservation Letters’, provides a reference for authorities, conservation ecologists and the public to guide them in preventing these invasive non-native species from becoming established and causing ecological and economic damage.

UKCEH ecologist Professor Helen Roy, who led the work, says: “These Territories are exceptionally biodiverse. St Helena, for example, has over 400 invertebrates found nowhere else in world – it is simply unique. We hope that this study draws attention to these Overseas Territories and the inspiring people on them who are working so hard to protect their incredible wildlife and habitats.”

To produce the list, experts from each UK Overseas Territory collaborated with the wider project team of experts from around the world to predict which invasive non-native species were likely to arrive, establish and impact on biodiversity, ecosystems, human health and the economy within the next 10 years. The report also examines how the species are most likely to arrive, with shipping containers identified as a key route for many animal species.

Gibraltar and Saint Helena are threatened by biological invasion from the greatest number of species overall. St Helena is most at risk from a high number of plant species, while the Falkland Islands and Tristan da Cunha are threatened by the most marine invasive non-native species.

One of the invasive non-native species that could pose a threat to many of the UK Overseas Territories is the green mussel (Perna viridis). It can ‘hitchhike’ around the world on ships and boats, and form dense colonies in places where it establishes outcompeting other species by, for example, reducing levels of phytoplankton – a key component of aquatic ecosystems.

Other invasive non-native species that present a major threat to many UK Overseas Territories include the little fire ant (Wasmannia auropunctata), the brown rat (Rattus norvegicus), and the mesquite tree (Prosopis juliflora) .

Dr Wayne Dawson of Durham University said: ““The knowledge and experience of local experts was central to identifying the non-native species that pose the highest threats to each Territory, and it was a great privilege to work with a wide range of contributors on the project.”

Ecologists and other experts on the UK Overseas Territories are aware of the challenges of invasive non-native species and in many cases have robust biosecurity measures in place, but Professor Roy hopes that the report will draw attention to their vital work.

Professor Roy added: “Preventing the introduction of invasive non-native species is key, because management of species that have established and spread is often extremely expensive and in some cases there are no options available. We hope that this list will help inform action, including supporting biosecurity activities, to safeguard the wildlife in these precious places.”

More effective protected areas needed to halt biodiversity loss

Protected natural areas of the UK are struggling to halt declines in insects and spiders that have occurred over the past 30 years, according to a new study led by researchers from the UK Centre for Ecology & Hydrology (UKCEH).

Nature reserves, Sites of Special Scientific Interest (SSSIs), Special Areas of Conservation and other forms of protected habitat have long been regarded as a key tool in conservation efforts to preserve and restore natural habitats.

But the new study, which collated nearly one million records for more than 1,230 invertebrate species between 1990 and 2018, suggests these protected areas are just as susceptible to the wider declines in biodiversity occurring across the country.

The authors found that protected areas were richer in species than unprotected areas of the country, but both areas have suffered similar rates of decline in native insects and spiders over the past 30 years.

Pollinators, such as bees and hoverflies, have suffered particularly severe declines, according to the findings.

The results suggest that while protected areas are helping to conserve valuable habitats and the species within them, they need more assistance to tackle wider threats posed by climate change, pollution and invasive species that are causing biodiversity loss across the country.

“We see parallel trends for invertebrates in both protected and unprotected areas,” said Dr Rob Cooke, an ecological modeller at UKCEH and lead author of the study. “It is worrying, as you would expect species to show more positive trends in protected areas.”

The declines found in the study equate to the loss of more than three species per decade for protected areas and less than two species per decade for unprotected areas.

The study, which is published in the journal Biological Conservation, used data from a number of different invertebrate recording schemes across the UK that contained observations of ants, bees, hoverflies, ladybirds, spiders and wasps. Dr Cooke, together with UKCEH colleagues Dr Francesca Mancini, Dr Robin Boyd, Dr Nick Isaac and researchers at the University of Sheffield, then examined changes in biodiversity through the study period.

They found there were almost double the number of rare species in protected areas compared to unprotected parts of the UK. The trends of these rare species also remained stable in both protected and unprotected areas, suggesting they were benefiting from conservation efforts. But the authors found strong declines for common species, especially in protected areas.

Dr Cooke said: “Protected areas are often designated specifically to help rare species. But the more common species appear to be falling through the cracks. It should serve as a warning as today’s common species can be tomorrow’s rare species.”

The researchers conclude that the large number of protected areas around the UK could play a bigger role in the future. Protected areas have supported some notable conservation success stories, such as the bittern, the ladybird spider and the chalkhill blue butterfly. But the authors suggest more can be done to ensure protected areas are benefitting all of the country’s biodiversity. They say evidence-based policies, targets and management focused more on the effectiveness, rather than just the coverage of protected areas, may be needed.

Dr Cooke added: “I think the positive thing we can take from this is that we have a clear opportunity to make protected areas better for biodiversity.”

Mountain ecosystems should be prioritised in biodiversity policies

More action is urgently needed to safeguard the world’s precious mountain ecosystems, according to a University of York researcher whose policy brief is being presented at this month’s United Nations Biodiversity Conference (“COP15”) in Montreal, Canada.

Professor Robert Marchant is calling on national governments to put mountain environments at the centre of their climate change and biodiversity policy efforts and actions.

The UN General Assembly named 2022 the International Year of Sustainable Mountain Development – some 20 years after the first International Year of Mountains. But while some successes have been achieved in that time, Professor Marchant says national policy simply isn’t keeping pace with land use change, development, population growth and the impacts of climate change on global mountain systems.

“Twenty years on, climates are still changing, populations are still growing, and mountain environments continue to be developed and transformed – but what hasn’t happened is any corresponding establishment of sustainable policies,” he explains. “Government environmental and business policies are rarely joined up and we are seeing continued widespread land degradation in mountain habitats. This includes uncontrolled grazing, deforestation, or overdevelopment – and much of it is resulting from weak policies and changing tenure laws.”

Mountains cover around a quarter of earth’s land mass. They host about half the world’s biodiversity hotspots. They are a hugely important component of global water supply because they receive more rain than lowland areas, experience less evaporation at high elevations, and contain large stores of water as snow and ice.

Well-functioning mountain ecosystems are more resilient to climate extremes – they can buffer shocks such as high intensity rainstorms or prolonged dry spells – and are important stores of carbon and storehouses of biodiversity.

Despite this, mountains don’t receive the corresponding policy attention and investment from their national governments. They are particularly vulnerable to climate change and human interventions, which threaten their globally important ecosystem services.

For example, the area around Mount Kilimanjaro in Kenya is an area of high population density and rapid economic development. It has seen a major expansion in agriculture over the past twenty years, as land has been privatised and companies have realised they can drill deep boreholes in the land to extract water from the mountain’s aquifer.

Professor Marchant notes: ““Once you’ve paid for that borehole, that water is a free resource to you. But these services are provided by nature – and no-one is presently paying for either the water resources or for stewardship of that land. Asking companies to pay for this kind of service, by issuing controllable permits for example, would be a step towards treating our mountain resources with more respect.”

Professor Marchant and his co-authors are calling on countries to invest more in mountain ecosystem restoration activities, and to formulate effective climate change policies that consider the unique nature and resources of mountains. Also urgently needed is more international information sharing and data collection on mountain use, as well as better analysis of the current restoration initiatives taking place around the world.

He says: “We are hoping for some progress at COP15, but what is really needed is an international treaty or code of practice that accepts the value of our mountain ecosystems, and I suspect that is some way off.”

Less intensively managed grasslands have better soil health

Researchers have shown – for the first time – that less intensively managed British grazed grasslands have on average 50% more plant species and better soil health than intensively managed grassland. The new study could help farmers increase both biodiversity and soil health, including the amount of carbon in the soil of the British countryside.

Grazed grassland makes up a large proportion of the British countryside and is vital to farming and rural communities. This land can be perceived as only being about food production, but this study gives more evidence that it could be key to increasing biodiversity and soil health.

Researchers at the UK Centre for Ecology & Hydrology (UKCEH) studied 940 plots of grassland, comparing randomly selected plots which sampled the range of grassland management across Great Britain; from intensively- managed land with a few sown grassland species and high levels of soil phosphorus (indicating ploughing/reseeding and fertiliser and slurry application), to grassland with higher levels of species and lower levels of soil phosphorus. The plots were sampled as part of the UKCEH Countryside Survey, a nationally representative long-term data set.

The study counted the number of plant species in sample areas and analysed co- located soil samples for numbers of soil invertebrates and carbon, nitrogen and phosphorus levels.

Researchers found that less intensively managed grassland had greater diversity of plant species and, strikingly, this correlated with better soil health, such as increased nitrogen and carbon levels and increased numbers of soil invertebrates such as springtails and mites.

In the same study, the researchers used the same methods to examine the plant diversity and soil from grasslands on 56 mostly beef farms from the Pasture Fed Livestock Association (PFLA) – a farmer group that has developed standards to manage and improve soil and pasture health.

The researchers found that plots of land from PFLA farms had greater plant diversity – on average an additional six plant species, including different types of grasses and herbaceous flowering plants, compared to intensively farmed plots from the Countryside Survey. In addition, grassland plants on these farms were often taller, a quality which is proven to be beneficial to butterflies and bees.

Pasture Fed Livestock Association grasslands did not yet show increased soil health, but the research indicated that this may be due to a time lag between increasing numbers of plant species and changes in soil health, particularly on farms which have been intensively managed in the past.

Lead author Dr Lisa Norton, Senior Scientist at UKCEH, says: “We’ve shown for the first time, on land managed by farmers for production, that a higher diversity of plants in grasslands is correlated with better soil health. This work also tells us that the Pasture Fed Livestock Association members are on the right track to increase biodiversity, though it may take longer to see improvements in soil health.

“Grassland with different types of plants able to grow tall and flower is associated with improved soil health measures, and is beneficial for creepy crawlies below and above ground. Having this abundance of life in our grasslands can in turn support small mammals and birds of prey, and farmers have told us that they are seeing voles and mice in their fields for the first time.”

Dr Norton adds: “My hope for the future is that our grasslands can be managed less intensively – with all the improvements in plant and animal biodiversity and soil health that brings – but still remain productive for farmers.”

The study was published in the journal Ecology Solutions and Evidence today [25 November, 2022] and was funded by the UK Research and Innovation Global Food Security Programme.

Low-traffic neighbourhoods reduce pollution in surrounding streets

Low-traffic neighbourhoods (LTNs) reduce traffic and air pollution without displacing the problem to nearby streets, new research has shown.

The study by Imperial College London looked at three LTNs in London, to identify their impact on both air pollution and traffic within the LTN zones and in the surrounding area.

LTNs aim to reduce through traffic in residential areas, usually by the use of barriers which prevent cars from using certain streets, while leaving them open to pedestrians and cyclists. Many LTNs were put in place during 2020, to prevent an increase in vehicle traffic as people avoided public transport through fear of infection. However, they also provoked opposition, with critics claiming that LTNs increased traffic and pollution in surrounding areas.

The researchers studied three LTNs in Islington, one of London’s most densely populated boroughs, which were put in place during 2020. The team compared pollution and traffic levels at monitoring stations inside the zones, on streets surrounding the zones, and at control sites further away, using data gathered by Islington Borough Council. The LTNs – in St Peter’s, Canonbury and Clerkenwell – were put in place between July and September 2020. The team analysed data gathered from July 2019 to February 2021.

Because each of the LTNs was set up at a different time and not all monitoring sites gathered data continuously, averaging out the results between the three LTNs would not provide an accurate overall picture. So the team carried out a more complex statistical analysis to ensure other factors that might affect traffic volumes and air pollution at particular times – such as the Covid restrictions in place, school holidays or weather – could be taken into account.

Using this analysis, the researchers found that concentrations of nitrogen dioxide fell by 5.7 percent within the LTNs and by just under nine percent on their boundaries, compared to the control sites. They also found that traffic dropped by over half inside the LTNs and by 13 percent at the boundaries, compared to the controls.

Dr Audrey de Nazelle, from Imperial’s Centre for Environmental Policy, said: “This research effectively disproves the argument that low-traffic zones will necessarily cause an increase in traffic and air pollution in neighbouring streets. In the three areas we looked at, they reduced both traffic volumes and, significantly, air pollution both inside and on the edges of the zone. Alongside the other benefits of LTNs that have been shown in previous research – such as improvements in safety and an increase in walking and cycling – this makes a very strong argument in their favour.”

Co-author, PhD student Helen Yang added: “This is the first study to use a robust statistical approach to show the impact of LTNs on surrounding areas, and the results are really encouraging. We worked with a relatively small data set and further research is now needed to confirm these findings at a larger scale.”

The research is published in Transportation Research Part D.