̽��ֱ�� of Cambridge - forest

Study uncovers earliest evidence of humans using fire to shape the landscape of Tasmania

sc604 — Fri, 15 Nov 2024 19:00:00 +0000

A team of researchers from the UK and Australia analysed charcoal and pollen contained in ancient mud to determine how Aboriginal Tasmanians shaped their surroundings. This is the earliest record of humans using fire to shape the Tasmanian environment.

Early human migrations from Africa to the southern part of the globe were well underway during the early part of the last ice age – humans reached northern Australia by around 65,000 years ago. When the first Palawa/Pakana (Tasmanian Indigenous) communities eventually reached Tasmania (known to the Palawa people as Lutruwita), it was the furthest south humans had ever settled.

These early Aboriginal communities used fire to penetrate and modify dense, wet forest for their own use – as indicated by a sudden increase in charcoal accumulated in ancient mud 41,600 years ago.

̽��ֱ��researchers say their results, reported in the journal Science Advances, could not only help us understand how humans have been shaping the Earth’s environment for tens of thousands of years, but also help understand the long-term Aboriginal-landscape connection, which is vital for landscape management in Australia today.

Tasmania currently lies about 240 kilometres off the southeast Australian coast, separated from the Australian mainland by the Bass Strait. However, during the last ice age, Australia and Tasmania were connected by a huge land bridge, allowing people to reach Tasmania on foot. ̽��ֱ��land bridge remained until about 8,000 years ago, after the end of the last ice age, when rising sea levels eventually cut Tasmania off from the Australian mainland.

“Australia is home to the world’s oldest Indigenous culture, which has endured for over 50,000 years,” said Dr Matthew Adeleye from Cambridge’s Department of Geography, the study’s lead author. “Earlier studies have shown that Aboriginal communities on the Australian mainland used fire to shape their habitats, but we haven’t had similarly detailed environmental records for Tasmania.”

̽��ֱ��researchers studied ancient mud taken from islands in the Bass Strait, which is part of Tasmania today, but would have been part of the land bridge connecting Australia and Tasmania during the last ice age. Due to low sea levels at the time, Palawa/Pakana communities were able to migrate from the Australian mainland.

Analysis of the ancient mud showed a sudden increase in charcoal around 41,600 years ago, followed by a major change in vegetation about 40,000 years ago, as indicated by different types of pollen in the mud.

“This suggests these early inhabitants were clearing forests by burning them, in order to create open spaces for subsistence and perhaps cultural activities,” said Adeleye. “Fire is an important tool, and it would have been used to promote the type of vegetation or landscape that was important to them.”

̽��ֱ��researchers say that humans likely learned to use fire to clear and manage forests during their migration across the glacial landscape of Sahul – a palaeocontinent that encompassed modern-day Australia, Tasmania, New Guinea and eastern Indonesia – as part of the extensive migration out of Africa.

“As natural habitats adapted to these controlled burnings, we see the expansion of fire-adapted species such as Eucalyptus, primarily on the wetter, eastern side of the Bass Strait islands,” said Adeleye.

Burning practices are still practiced today by Aboriginal communities in Australia, including for landscape management and cultural activities. However, using this type of burning, known as cultural burning, for managing severe wildfires in Australia remains contentious. ̽��ֱ��researchers say understanding this ancient land management practice could help define and restore pre-colonial landscapes.

“These early Tasmanian communities were the island’s first land managers,” said Adeleye. “If we’re going to protect Tasmanian and Australian landscapes for future generations, it’s important that we listen to and learn from Indigenous communities who are calling for a greater role in helping to manage Australian landscapes into the future.”

̽��ֱ��research was supported in part by the Australian Research Council.

Reference:
Matthew A Adeleye et al. ‘Landscape burning facilitated Aboriginal migration into Lutruwita/Tasmania 41,600 years ago.’ Science Advances (2024). DOI: 10.1126/sciadv.adp6579

Some of the first human beings to arrive in Tasmania, over 41,000 years ago, used fire to shape and manage the landscape, about 2,000 years earlier than previously thought.

Simon Haberle

Emerald Swamp, Tasmania

̽��ֱ��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 – 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.

Yes

Planting trees in the Arctic could make global warming worse, not better, say scientists

sc604 — Thu, 07 Nov 2024 13:41:21 +0000

But, writing in the journal Nature Geoscience, an international group of scientists, led by the ̽��ֱ�� of Cambridge and the ̽��ֱ�� of Århus, argue that tree planting at high latitudes will accelerate, rather than decelerate, global warming.

As the climate continues to warm, trees can be planted further and further north, and large-scale tree-planting projects in the Arctic have been championed by governments and corporations as a way to mitigate the worst effects of climate change.

However, when trees are planted in the wrong places - such as normally treeless tundra and mires, as well as large areas of the boreal forest with relatively open tree canopies - they can make global warming worse.

According to lead author Assistant Professor Jeppe Kristensen from Aarhus ̽��ֱ�� in Denmark, the unique characteristics of Arctic and sub-Arctic ecosystems make them poorly suited for tree planting for climate mitigation.

“Soils in the Arctic store more carbon than all vegetation on Earth,” said Kristensen. “These soils are vulnerable to disturbances, such as cultivation for forestry or agriculture, but also the penetration of tree roots. ̽��ֱ��semi-continuous daylight during the spring and early summer, when snow is still on the ground, also makes the energy balance in this region extremely sensitive to surface darkening, since green and brown trees will soak up more heat from the sun than white snow.”

In addition, the regions surrounding the North Pole in North America, Asia and Scandinavia are prone to natural disturbances - such as wildfires and droughts - that kill off vegetation. Climate change makes these disturbances both more frequent and more severe.

“This is a risky place to be a tree, particularly as part of a homogeneous plantation that is more vulnerable to such disturbances,” said Kristensen. “ ̽��ֱ��carbon stored in these trees risks fuelling disturbances and getting released back to the atmosphere within a few decades.”

̽��ֱ��researchers say that tree planting at high latitudes is a prime example of a climate solution with a desired effect in one context but the opposite effect in another.

“ ̽��ֱ��climate debate is very carbon-focused because the main way humans have modified the Earth’s climate in the last century is through emitting greenhouse gases from burning fossil fuels,” said Kristensen. “But at the core, climate change is the result of how much solar energy entering the atmosphere stays, and how much leaves again – Earth’s so-called energy balance.”

Greenhouse gases are one important determinant of how much heat can escape our planet’s atmosphere. However, the researchers say that at high latitudes, how much sunlight is reflected back into space, without being converted into heat (known as the albedo effect), is more important than carbon storage for the total energy balance.

̽��ֱ��researchers are calling for a more holistic view of ecosystems to identify truly meaningful nature-based solutions that do not compromise the overall goal: slowing down climate change.

“A holistic approach is not just a richer way of looking at the climate effects of nature-based solutions, but it’s imperative if we’re going to make a difference in the real world,” said senior author Professor Marc Macias-Fauria, from the ̽��ֱ�� of Cambridge’s Scott Polar Research Institute.

However, the researchers recognise that there can be other reasons for planting trees, such as timber self-sufficiency, but these cases do not come with bonuses for climate mitigation.

“Forestry in the far North should be viewed like any other production system and compensate for its negative impact on the climate and biodiversity,” said Macias-Fauria. “You can’t have your cake and eat it, and you can’t deceive the Earth. By selling northern afforestation as a climate solution, we’re only fooling ourselves.”

So how can we moderate global warming at high latitudes? ̽��ֱ��researchers suggest that working with local communities to support sustainable populations of large herbivores, such as caribou, could be a more viable nature-based solution to climate change in Arctic and subarctic regions than planting millions of trees.

“There is ample evidence that large herbivores affect plant communities and snow conditions in ways that result in net cooling,” said Macias-Fauria. “This happens both directly, by keeping tundra landscapes open, and indirectly, through the effects of herbivore winter foraging, where they modify the snow and decrease its insulation capacity, reducing soil temperatures and permafrost thaw.”

̽��ֱ��researchers say it’s vital to consider biodiversity and the livelihoods of local communities in the pursuit of nature-based climate solutions.

“Large herbivores can reduce climate-driven biodiversity loss in Arctic ecosystems and remain a fundamental food resource for local communities,” said Macias-Fauria. “Biodiversity and local communities are not an added benefit to nature-based solutions: they are fundamental. Any nature-based solutions must be led by the communities who live at the front line of climate change.”

More about this story

Reference:
Jeppe Å Kristensen et al. ‘Tree planting is no climate solution at northern high latitudes.’ Nature Geoscience (2024). DOI: 10.1038/s41561-024-01573-4

Explore more discoveries, innovations and research on climate and nature at the ̽��ֱ�� of Cambridge: www.cam.ac.uk/climate-and-nature

Tree planting has been widely touted as a cost-effective way of reducing global warming, due to trees’ ability to store large quantities of carbon from the atmosphere.

Pierre Longnus via Getty Images

Emerald Lake, Yukon

Yes

Global timber supply threatened as climate change pushes cropland northwards

jg533 — Thu, 29 Aug 2024 08:49:54 +0000

̽��ֱ��sight of vineyards in Britain is becoming more common as hotter summers create increasingly suitable conditions for growing grapes. But behind this success story is a sobering one: climate change is shifting the regions of the world suitable for growing crops.

Researchers at the ̽��ֱ�� of Cambridge have uncovered a looming issue: as the land suitable for producing our food moves northwards, it will put a squeeze on the land we need to grow trees. ̽��ֱ��timber these trees produce is the basis of much of modern life – from paper and cardboard to furniture and buildings.

They say that the increasing competition between land for timber production and food production due to climate change has, until now, been overlooked – but is set to be an emerging issue as our demand for both continues to increase.

Under the worst-case scenario for climate change, where no action is taken to decarbonise society, the study found that over a quarter of existing forestry land – around 320 million hectares, equivalent to the size of India – will become more suitable for agriculture by the end of the century.

Most forests for timber production are currently located in the northern hemisphere in the US, Canada, China and Russia. ̽��ֱ��study found that 90% of all current forestry land that will become agriculturally productive by 2100 will be in these 4 countries.

In particular, tens of millions of hectares of timber-producing land across Russia will become newly suitable for agriculture – more than in the US, Canada and China put together – with conditions becoming favourable for potato, soy, and wheat farming.

“There’s only a finite area of suitable land on the planet where we can produce food and wood - 2 critical resources for society. As climate change worsens and agriculture is forced to expand northwards, there’s going to be increasing pressure on timber production,” said Dr Oscar Morton, a researcher in the ̽��ֱ�� of Cambridge’s Department of Plant Sciences who co-led the study.

“We’ve got to be thinking 50 years ahead because if we want timber in the future, we need to be planting it now. ̽��ֱ��trees that will be logged by the end of this century are already in the ground – they’re on much slower cycles than food crops,” said Dr Chris Bousfield, a postdoctoral researcher in the ̽��ֱ�� of Cambridge’s Department of Plant Sciences and co-leader of the study.

Global food demand is projected to double by 2050 as the population grows and becomes more affluent. Global wood demand is also expected to double in the same timeframe, in large part because it is a low-carbon alternative to concrete and steel for construction.

Shifting timber production deeper into boreal or tropical forests are not viable options, because the trees in those regions have stood untouched for thousands of years and logging them would release huge amounts of carbon and threaten biodiversity.

“A major environmental risk of increasing competition for land between farming and forestry is that wood production moves into remaining areas of primary forest within the tropics or boreal zones. These are the epicentres of remaining global wilderness and untouched tropical forests are the most biodiverse places on Earth. Preventing further expansion is critical,” said David Edwards, Professor of Plant Ecology in the ̽��ֱ�� of Cambridge’s Department of Plant Sciences and senior author of the study.

To get their results, the researchers took satellite data showing intensive forestry across the world and overlaid it with predictions of suitable agricultural land for the world’s key crops -including rice, wheat, maize, soy and potato - in the future under various climate change scenarios.

Even in the best-case scenario, where the world meets net-zero targets, the researchers say there will still be significant future changes in the regions suitable for timber and crop production.

̽��ֱ��study is published in the journal Nature Climate Change.

Timber production contributes over US $1.5 trillion (about £1.1 trillion) per year to national economies globally. Heatwaves and associated wildfires have caused huge recent losses of timber forests around the world. Climate change is also driving the spread of pests like the Bark Beetle, which attacks trees.

Climate change is expected to cause areas in the tropics to become too hot and inhospitable for growing food and make large areas of southern Europe much less suitable for food and wood production.

“Climate change is already causing challenges for timber production. Now on top of that, there will be this increased pressure from agriculture, creating a perfect storm of problems,” said Bousfield.

“Securing our future wood supply might not seem as pressing as securing the food we need to eat and survive. But wood is just as integrated within our daily lives and we need to develop strategies to ensure both food and wood security into the future,” said Morton.

Reference

Bousfield, C G, et al, ‘Climate change will exacerbate land conflict between agriculture and timber production.’ Nature Climate Change (2024). DOI: 10.1038/s41558-024-02113-z

Climate change will move and reduce the land suitable for growing food and timber, putting the production of these 2 vital resources into direct competition, a new study has found.

Gianluca Cerullo

Timber/farming contrast in the USA

Yes

AI takes flight to revolutionise forest monitoring

plc32 — Fri, 26 Jul 2024 14:43:32 +0000

Cambridge researchers are harnessing artificial intelligence to improve how forests are monitored. Associate Professor Dr Emily Lines and Research Associate Dr Harry Owen are using billions of laser-captured data points to measure biodiversity and make carbon accounting more accurate.

Earth’s earliest forest revealed in Somerset fossils

sc604 — Thu, 07 Mar 2024 10:27:02 +0000

̽��ֱ��oldest fossilised forest known on Earth – dating from 390 million years ago – has been found in the high sandstone cliffs along the Devon and Somerset coast of South West England.

̽��ֱ��Fens of eastern England once held vast woodlands

sc604 — Fri, 24 Nov 2023 05:23:59 +0000

̽��ֱ��Fens of eastern England, a low-lying, extremely flat landscape dominated by agricultural fields, was once a vast woodland filled with huge yew trees, according to new research.

Experts predict ‘catastrophic ecosystem collapse’ of UK forests within the next 50 years if action not taken

cg605 — Wed, 08 Nov 2023 00:05:54 +0000

A team of experts from across Europe has produced a list of 15 over-looked and emerging issues that are likely to have a significant impact on UK forests over the next 50 years.

This is the first ‘horizon scanning’ exercise – a technique to identify relatively unknown threats, opportunities, and new trends – of UK forests. ̽��ֱ��aim is to help researchers, practitioners, policymakers, and society in general, better prepare for the future and address threats before they become critical.

Dr Eleanor Tew, first author, visiting researcher at Cambridge’s Department of Zoology and Head of Forest Planning at Forestry England said: “ ̽��ֱ��next 50 years will bring huge changes to UK forests: the threats they face, the way that we manage them, and the benefits they deliver to society.”

Forestry England, a part of the Forestry Commission, collaborated with the ̽��ֱ�� of Cambridge on the study, which was published today in the journal, Forestry.

A panel comprising 42 experts, who represented a range of professions, organisations, and geographies, reached out to their networks to seek over-looked and emerging issues that were likely to affect UK forests over the next half a century. ̽��ֱ��resulting 180-item longlist was then whittled down through a series of review exercises to a shortlist of 30 issues. In a final workshop, panellists identified the top 15 issues they believed were likely to have the greatest impact on UK forests in the next 50 years.

̽��ֱ��research method did not support the overall ranking of the 15 issues in order of importance or likelihood of occurrence. However, when the issues were scored individually by the panel of experts, it was notable that ‘catastrophic forest ecosystem collapse’ was the most highly ranked issue, with 64% of experts ranking it as their top issue and 88% ranking it within their top three.

‘Catastrophic forest ecosystem collapse’ refers to multiple interrelated hazards that have a cascading effect on forests, leading to their total or partial collapse. This has already been witnessed in continental Europe and North America.

Tew said: “We hope the results from this horizon scanning exercise serve as an urgent call to action to build on, and dramatically upscale, action to increase forest resilience.”

Another issue identified was that droughts caused by climate change may lead to competition for water resources between forests and society. On the other hand, forests may help to mitigate the impact of floods caused by climate change.

Tree viral diseases were also identified as an issue. In the UK, pests and pathogens are increasing due to globalisation and climate change, with viruses and viroids (RNA molecules) being the largest group on the UK Plant Health Risk Register. However, little is known about how viral diseases affect forest tree species and indeed the wider ecosystem.

A further issue was the effect of climate change on forest management, with extreme weather leading to smaller windows of time when forestry can be carried out. Experts warn that the seasons for carrying out work such as harvesting and thinning are getting narrower as we see wetter winters and scorching summers.

However not all emerging issues are threats – some are new opportunities. For example, trees will be at the heart of future urban planning. Experts predict that ‘forest lungs’ will be created thanks to an increased understanding of the benefits of trees for society. They say there will likely be a greater blurring of boundaries between urban and rural areas, with an increase in green infrastructure and connectivity.

International commitments around nature are also likely to have repercussions at the local level. For example, the mandatory reporting of companies’ supply chain impacts on nature, such as through the new framework being developed by the Taskforce on Nature-related Financial Disclosures (TNFD), could create additional incentives for nature-friendly forest management.

Tew concluded: “These results are both concerning and exciting. However, we should be optimistic, remembering that these are possibilities and not certainties. Crucially, we have time to act ‒ by responding to the threats and embracing the opportunities, future generations can have resilient forests with all the benefits they offer.”

Senior author and pioneer of horizon scanning, Professor Bill Sutherland, from the Department of Zoology at the ̽��ֱ�� of Cambridge said: “We are already seeing dramatic events in Europe’s forests whether fires, disease or bark beetles, whilst the importance of trees is increasingly recognised. Horizon scanning to identify future issues is key, especially as trees planted now will face very different circumstances as they mature in scores of years.”

This research was funded by Forestry England. ̽��ֱ��Forestry Commission is bringing the sector together in 2024 to look at next steps.

Tew et al, A horizon scan of issues affecting UK forest management within 50 years, Forestry DOI: 10.1093/forestry/cpad047

Other threats to UK forests include competition with society for water, viral diseases, and extreme weather affecting forest management.

̽��ֱ��next 50 years will bring huge changes to UK forests: the threats they face, the way that we manage them, and the benefits they deliver to society.

Dr Eleanor Tew, visiting researcher at Cambridge’s Department of Zoology and Head of Forest Planning at Forestry England

Graham Custance Photography / Moment via Getty Images

Ashridge, Hertfordshire, UK

̽��ֱ��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.

Yes

Foresters bring Cambridge 'water curriculum' to Indian Himalayas

plc32 — Thu, 29 Jun 2023 09:13:44 +0000

‘Pani Pahar - the Water Curriculum', jointly developed by researchers at the ̽��ֱ�� of Cambridge and the Hearth Advisors, a division of Canta Consultants LLP will form the central education platform within a programme of tree plantation drives, waste management and recycling that engages students, communities, village councils and towns across an area that contains about a quarter of all India's forests.

Designed for students between the ages of 9 and 15, the Pani Pahar curriculum has been freely available to teachers and schools since 2020. ̽��ֱ��aim of the curriculum is to engage students in experiential learning and to instil in them a sense of responsibility towards water conservation, and environmental sustainability more generally. ̽��ֱ��curriculum preparation and instructional design was led by the Hearth Advisors, based on research conducted at the ̽��ֱ�� of Cambridge.

Young Nagaland forestry graduates under the Mobius Young Professional Programme are being trained by the Hearth Advisors to impart the Pani Pahar curriculum in schools, collect data on ‘indigenous knowledge and practices in forest management/natural resource management’ and contribute to an international research initiative ‘to translate indigenous knowledge into concrete policy action’ launched by the Indian government at COP 27.

̽��ֱ��foresters will also be given hands-on training and work experience on various aspects of forestry projects by a team from the Nagaland Forest Management Project (NFMP). ̽��ֱ��NFMP is a development project “to improve forest ecosystems” supported by the Japan International Cooperation Agency (JICA) of the Japanese government.

̽��ֱ��Nagaland project is led by Cambridge alumnus Atoho Jakhalu, who is Director of the Climate Studies and Knowledge Solutions Centre in the Government of Nagaland, supported by the Government Department of Environment, Forests and Climate Change, Hearth Advisors, as well as YouthNet, and funded by the Mobius Foundation.

“We anticipate the success of this project in Nagaland will set a strong foundation to be followed for the rest of the other seven North Eastern states of the Indian Himalayan region (which has a quarter of India’s total forest cover and therefore has a huge role to play in keeping up with India’s climate commitments especially in the forestry sector),” Jakhalu said.

‘Pani Pahar – Waters of the Himalayas' grew out of a collaborative research project between the ̽��ֱ�� of Cambridge, ̽��ֱ��Centre for Ecology Development and Research in India (CEDAR) and the Southasia Institute for Advanced Studies in Nepal (SIAS). ̽��ֱ��project explores the changing landscapes and escalating water crises of the Indian Himalayas. It combines academic research led by Cambridge Pro-Vice-Chancellor for Education Professor Bhaskar Vira and Dr Eszter Kovacs then at Cambridge’s Department of Geography (now at ̽��ֱ�� College London) with contemporary imagery by photojournalist Toby Smith, which has been exhibited in the UK and India.

̽��ֱ��curriculum, developed by the Hearth Advisors, aims to help students understand water resources and sustainability and how these are impacted by climate change. ̽��ֱ��detailed lesson plans encourage reflection and research on the human causes of water scarcity, and some of the effects of environmental change on humans and our shared resources. It also helps students understand the meaning of activism, recognise some of the challenges associated with activism, and begin to associate activism with the needs and issues of their school.

“These school materials are designed to allow young people, who are highly mobilised through the school strikes for climate, to develop a critical engagement with these issues, with learning resources and educational materials that are targeted at different stages of the secondary school curriculum,” said Vira. “We wanted to show the links between our research on water scarcity and broader concerns about environmental change and crises.”

̽��ֱ��curriculum has three sets, one for each level, involving 10-hours of contact time with students on each level. ̽��ֱ��curriculum is targeted at students of junior, middle and senior level.

̽��ֱ��curriculum was launched in India in 2020, although Vira says it could easily be incorporated into the school systems of other countries, including the UK. ̽��ֱ��resources are free to download and use, and have been released through creative commons licensing.

Funding for the research project and exhibition was provided by the UK’s Ecosystem Services for Poverty Alleviation (ESPA) programme, which was a joint initiative of the UK Department for International Development (DFID), Natural Environment Research Council (NERC) and Economic and Social Research Council (ESRC). Funding was also provided by the ̽��ֱ�� of Cambridge’s Economic and Social Research Council Impact Acceleration Account. ̽��ֱ��Oxonian India Foundation funded the graphic design of the curriculum materials.

Foresters across the mountainous northeastern Indian state of Nagaland will help roll out a unique programme of environmental education, co-developed by researchers at the ̽��ֱ�� of Cambridge.

Toby Smith

A young child drinks from a water tap

̽��ֱ��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.

Yes