̽��ֱ�� of Cambridge - Lancaster ̽��ֱ��

Roadside hedges can reduce harmful ultrafine particle pollution around schools

cmm201 — Wed, 13 Sep 2023 14:19:33 +0000

̽��ֱ��research, a collaboration with Lancaster ̽��ֱ��, found that hedges can act as protective barriers against air pollution from major city roads by soaking up significant quantities of harmful particles emitted by traffic.

̽��ֱ��researchers applied a new type of pollution analysis, using magnetism to study particles trapped by a hedge separating a major 6-lane road from a primary school in Manchester, UK. They found that the hedge was especially successful in removing ultrafine particle pollution, which can be more damaging to health.

“Our findings show that hedges can provide a simple, cheap and effective way to help reduce exposure to local sources of pollution,” said lead author Hassan Sheikh from Cambridge’s Department of Earth Sciences.

̽��ֱ��new study differs from conventional air pollution studies because the researchers specifically measured magnetic particles, which originate from vehicle exhaust and the wearing of brake pads and tyres. That allowed them to distinguish local traffic pollution from other sources of air pollution.

In England alone, epidemiological studies estimate that 26,000 to 38,000 deaths and thousands of NHS hospital admissions are linked to dust-like particles carried in air pollution — much of which is generated by heavy traffic in urban environments.

This particle pollution — or particulate matter — is made up of a variety of chemical compounds, metals and other materials, some of which are toxic. ̽��ֱ��bigger particles (which are still tiny) measure less than 10 microns in diameter (called PM10) and are easily inhaled. Finer particles of less than 2.5 microns across (PM2.5) can penetrate deeper into the lungs and are small enough to enter the bloodstream.

Children attending schools next to busy roads are especially vulnerable to the effects of air pollution because their airways are still developing and they breath faster than adults.

Sheikh and the team studied magnetic particles captured by a western red cedar ‘tredge’ (trees managed at head-height), which was previously installed outside St Ambrose Primary School as part of a trial led by Lancaster ̽��ֱ��.

“Western red cedar does a great job in 'capturing ' particulate pollution because it has abundant, fine, evergreen leaves into which airborne particles bump and then settle from the roadside air,” said study co-author Professor Barbara Maher from the Lancaster ̽��ֱ��, who led the previous research.

Sheikh and the team measured particles of varying sizes on the leaves of the tredge and used air filters to measure particle abundance at intervals downwind toward the school playground.

They also developed a new experiment that used a tracer gas to understand how ultrafine particles (measuring less that 2.5 microns) moved through and were trapped by the tredge.

Their results revealed that there was a substantial reduction in particle pollution downwind of the tredge. “ ̽��ֱ��tredge acts as a permeable barrier, intercepting and capturing particles effectively on its leaves,” said Sheikh.

In the school playground, 30 metres from the road, they measured a 78% decrease in PM10 relative to roadside air.

They noticed that this removal was even more efficient for ultrafine PM2.5 particles. “What was remarkable was just how efficiently the tredge hoovered up the very finest particles,” said senior author Professor Richard Harrison, also from Cambridge’s Department of Earth Sciences. They measured an 80% reduction in the ultrafine particles just behind the tredge.

They think the ultrafine particles are preferentially filtered out by the tredge because they have a higher likelihood of being captured on the ridged surfaces of the red cedar leaves than coarser particles.

However, they did note a slight uptick in levels of magnetic PM2.5 in the playground, although they were still 63% below roadside air. “ ̽��ֱ��ultrafine particles were very effectively removed, but this shows that some air still goes over or around the tredge,” said Sheikh. Less is currently known about how particulate matter moves and disperses at this higher level, where air mixes around buildings and trees.

“That means the design and placement of tredges near playgrounds and schools should be carefully considered so that their ability to soak up particles can be used to maximum effect,” said Harrison.

Cllr Tracey Rawlins, Executive Member for Environment for Manchester City Council, said: "We were keen to be part of this study as Manchester seeks to embrace innovation in our efforts to become a greener city with cleaner air and tackle climate change.

" ̽��ֱ��findings underline the contribution which nature-based innovations can make to rising to that challenge. We look forward to delivering more green screens as well as many trees at school sites, complementing our education climate change strategy," said Rawlins.

Previously, Sheikh and Harrison used their new magnetic analysis to identify high levels of ultrafine particles polluting the London Underground. They now plan on working with colleagues at the MRC Toxicology Unit in Cambridge to find out what happens when cells are exposed to this type of ultrafine particle pollution.

Reference

Sheikh, H A, Maher, B A, Woods, A W, Tung, P Y, and Harrison, R J (2023). Efficacy of green infrastructure in reducing exposure to local, traffic-related sources of airborne particulate matter (PM). Science of the Total Environment, 166598.

A new study led by Cambridge ̽��ֱ�� confirms that planting hedges between roadsides and school playgrounds can dramatically reduce children’s exposure to traffic-related particle pollution.

Our findings show that hedges can provide a simple, cheap and effective way to help reduce exposure to local sources of pollution

Hassan Sheikh

H A Sheikh

Monitoring particle air pollution either side of the tredge installed at St Ambrose primary school, Manchester

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

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Lack of evidence hampers progress on corporate-led ecosystem restoration

jg533 — Fri, 08 Sep 2023 07:47:52 +0000

An international team of scientists has analysed publicly available sustainability reports released by 100 of the world’s largest companies and found that despite many businesses claiming to actively rebuild damaged ecosystems, very little is known about what is actually being achieved.

Efforts to rebuild degraded environments are vital for achieving global biodiversity targets, and corporate-led projects offer huge potential to restore damaged and lost ecosystems around the globe.

But the study reveals that over 90 percent of corporate-led restoration projects fail to report a single ecological outcome. Around 80 percent of projects do not reveal how much money is invested in restoration, and a third fail to even state the area of habitat that they aim to restore.

̽��ֱ��United Nations has launched a Decade on Ecosystem Restoration, and in recent years businesses around the world have collectively pledged to plant billions of trees, hundreds of thousands of corals and tens of thousands of mangroves. Around two thirds of the top 100 largest global corporations undertake ecosystem restoration.

̽��ֱ��study is published in the journal Science.

“Ultimately, if big businesses are going to contribute effectively to the UN Decade on Ecosystem Restoration, there needs to be transparency and consistency in reporting,” said Professor Rachael Garrett, Moran Professor of Conservation and Development at the ̽��ֱ�� of Cambridge Conservation Research Institute, and a co-author of the report.

She added: “This is in the interest of the businesses themselves, who stand to gain from demonstrating to their customers, shareholders, employees and the wider public that they are making meaningful impacts with their declared restoration efforts.

“ ̽��ֱ��world’s largest corporations have the potential to lift ecosystem restoration efforts to an unprecedented scale. But their involvement has to be managed with proper evidence and accountability, to make sure the outcomes are beneficial and fair for everyone.”

Many countries require businesses to conduct Environmental Impact Assessments (EIAs) to quantify and reduce their environmental damage, and other private-sector initiatives also encourage companies to measure and disclose their biodiversity impacts. However, the study finds that current guidelines and legal frameworks around ecosystem restoration are inadequate, and are not yet resulting in appropriate reporting by businesses.

̽��ֱ��researchers are calling for more transparency around the reporting of corporate-led ecosystem restoration projects, and for reporting to be more consistently centred around scientific principles that determine ecosystem restoration success.

“Restoring degraded ecosystems is an urgent challenge for this decade, and big businesses have the potential to play a vital role,” said Dr Tim Lamont at Lancaster ̽��ֱ��, lead author of the study.

He added: "With their size, resources and logistics expertise, they could help deliver the large-scale restoration we need in many places. But at the moment there is very little transparency, which makes it hard for anyone to assess if projects are delivering benefits for ecosystems or people.

“When a business says it has planted thousands of trees to restore habitat and soak up carbon – how do we know if this has been delivered, if the trees will survive, and if it has resulted in a functioning ecosystem that benefits biodiversity and people? In many cases, we’ve found that the evidence provided by large corporations to support their claims is insufficient.”

̽��ֱ��researchers say new improved reporting guidelines around ecosystem restoration should:

Recommend that companies clearly differentiate between restoration activities that merely mitigate the negative environmental impacts of a business’ operations from those that aim to provide wider climate, biodiversity and social justice outcomes.
Recommend a principle-based approach, drawing from conservation science, for planning and reporting, so that restoration projects in a range of different contexts can all maintain high standards across core areas.
Ensure corporations engage with and empower local stakeholders to co-design restoration projects from the outset.

Reference

Lamont, T, et al: 'Hold big business to task on ecosystem restoration: corporate reporting must embrace holistic principles from restoration science.' Sept 2023, Science. DOI: 10.1126/science.adh2610

Adapted from a press release by Lancaster ̽��ֱ��.

A near total lack of transparency is making it impossible to assess the quality of corporate-led ecosystem restoration projects, a new study finds.

̽��ֱ��world’s largest corporations have the potential to lift ecosystem restoration efforts to an unprecedented scale. But their involvement has to be managed with proper evidence and accountability, to make sure the outcomes are beneficial and fair for everyone.

Rachael Garrett

Tim Lamont

Degraded coral reef 'rubblefield' in Indonesia

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Attribution

Provide shady spots to protect butterflies from climate change

jg533 — Thu, 24 Sep 2020 06:32:49 +0000

Researchers have discovered significant variations in the ability of different UK butterfly species to maintain a suitable body temperature. Species that rely most on finding a suitably shady location to keep cool are at the greatest risk of population decline.

Amazonia at a crossroads

sj387 — Thu, 17 Oct 2013 08:00:04 +0000

̽��ֱ��numbers associated with the Amazon are truly staggering. It encompasses nine countries; contains at least a tenth of the known species in the world; provides a home and resources to 31 million people; stores the equivalent amount of carbon to a decade of human-induced emissions for the entire planet; and discharges a fifth of the world’s fresh water.

However, rapid social and ecological change, borne on the back of deforestation, harvesting of natural resources and a changing climate, has left the future of the world’s largest remaining tropical forest uncertain – Amazonia, today, is “standing at a crossroads”, as Dr Toby Gardner describes.

He points to the existence of tough trade-offs that underpin the region’s challenges: “ ̽��ֱ��demand for land and natural resources is driven by the development needs of one of the world’s largest emerging economies, as well as by the insatiable global food and commodities market. Understanding what management practices can best achieve both economic development and environmental conservation is central to addressing this challenge and shepherding the creation of a more sustainable Amazon.”

Gardner leads a new research programme that is motivated by helping to solve this dilemma – the Sustainable Amazon Network – alongside colleagues at Lancaster ̽��ֱ��, the Goeldi Museum in Belém (Brazil) and the Brazilian Agricultural Research Corporation (Embrapa), with funding from the Brazilian and UK governments and ̽��ֱ��Nature Conservancy, among others.

̽��ֱ��Network’s 100-strong group of researchers and students from over 30 institutions are working with conservation organisations, farmers and government officials. Their approach is to assemble an evidence base on the sustainability challenges and ecological consequences associated with land uses and management strategies, and to use this to test the effectiveness and risks of alternative policy choices facing local people and regional governments.

At the heart of the research is an appreciation of the complex array of interactions and feedbacks that characterise the changing face of Amazonia. ̽��ֱ��project takes as its ‘laboratory’ two regions of the eastern Amazon: Paragominas, a region infamous for lawlessness, violence, land grabbing, illegal sawmills and rampant forest clearance until the 1990s; and Santarém-Belterra, once a centre of pre-Colombian civilisation, with a long history of farming and now home to smallholder farms and larger agricultural enterprises.

What makes the project distinct from many other research initiatives is the collection of matched data from the same network of landholdings on changes in both the ecological and the socio-economic characteristics of different land and forest use systems. ̽��ֱ��team’s survey design has enabled information to be collected across the full wealth spectrum, from the poorest to the richest farmers, while allowing comparisons at multiple spatial scales – between different farms, catchments and regions.

̽��ֱ��result is one of the most comprehensive field assessments ever undertaken in the tropics. Critical issues that are being addressed include the identification of potential threshold effects of deforestation on the degradation of ecological systems, and the identification of strategies at both farm and municipality scales that can effectively reconcile conservation and development goals.

“In addition, one of the longer term implications of any initiative like this is the fact that a large group of students and researchers, many of whom are Brazilian, have been exposed to new ideas and new ways of thinking about sustainability problems, and this, perhaps above anything else, will be the most valuable legacy of our project,” added Gardner.

Can the world’s largest tropical forest biome be transformed into a sustainable ecological system? “There is a short window of opportunity and there is potential for recovery,” said Gardner. “But we cannot afford to be complacent.”

̽��ֱ��Amazon rainforest faces an uncertain future – one that an international research network hopes to help steer towards sustainability.

There is a short window of opportunity and there is potential for recovery, but we cannot afford to be complacent

Toby Gardner

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