By Jesús Aguirre Gutiérrez, researcher at the Environmental Change Institute, School of Geography and the Environment, University of Oxford, and the Naturalis Biodiversity Centre, The Netherlands.
The tropical forest canopy is one of the Earth’s underexplored frontiers. To understand how these unique environments respond to climate change a team from the Ecosystems Lab at the University of Oxford and partner institutes in Ghana gathered evidence from the treetops, finding drier forests are at greater risks.
Our natural world is facing unprecedented changes in the distribution of biodiversity – the variety of life on earth – at local and global scales. Around one million species are threatened with extinction, posing an imminent threat to the functioning of ecosystems and to human wellbeing.
Image: A tree climber collecting leaf samples 30 m up a rainforest tree (Ankasa, Ghana). © Yadvinder Malhi.
In our new study, recently published in Nature Communications, we investigate if and how climate change has affected the diversity of tropical ecosystems in West Africa over the last decades. In particular, we wanted to understand if wetter and drier tropical forests responded in different ways to the same drivers of change.
For this study we conducted fieldwork in Ghana over six months. The field campaign was led by Dr Imma Oliveras and Dr Stephen Adu Bredu and coordinated by co-authors Theresa Peprah and Agne Gvozdevaite. It formed part of a global effort. More than 25 research assistants from KNUST University and Forestry Institute of Ghana (FORIG) participated in the field campaign and were trained in the sampling techniques and scientific protocols for undertaking the research.
Image: Albert Aryee labels plastic bags for collecting samples of leaves. All bags must be labelled with a unique code so that each leaf can be tracked to a branch, tree, and site. © Imma Oliveras
During the campaign we visited clusters of sample plots at three sites, stretching along a climate gradient from humid ancient rainforest through to parched try forest and savanna. We sampled leaves and branches from 299 trees. These were very long days, usually starting at 4.30 am with a group breakfast and by 6 am we would be already working in the field. We would finish the fieldwork at around 3 pm and then work in the field laboratories until 10 pm. Some of the research assistants – who were masters and undergraduate students at the time – have pursued further postgraduate studies after the experience and successfully found scholarships in Ghana, Europe and the US.
Image: Working in the field laboratory. © Imma Oliveras
When starting this research, we expected that a drying trend would be reflected in overall diversity decreases for all tropical forests. However, we found that forest communities in drier sites experienced on average stronger declines in functional, taxonomic and phylogenetic diversity across time than forest communities in wetter areas.
This means that drier forests are transitioning towards increasingly more homogenous forest communities, diverging further from wetter forests in functional, taxonomic and phylogenetic diversity. In contrast, wetter forests showed on average increases in functional and taxonomic diversity, which could be the result of their higher atmospheric and ground water availability in comparison to that available for drier forests. Overall, climatic and soil conditions partly explained the changes in diversity and differences in responses between drier and wetter tropical forests in West African.
Stephen Adu-Bredu and Theresa Peprah from CSIR-Forestry Research Institute of Ghana, described that some of the most challenging things to do during the fieldwork were waking up daily at 3am in order to get to the field around 4am for predawn water potential measurements, as well as climbing of the trees at this hour of the day. They say: ‘The dry season CO2 exchange measurement was difficult and frustrating. One can spend over an hour or even a day on a single leaf, and the measurements are to be carried on three leaves per branch, as the protocol demands.’
Dr Imma Oliveras, senior study author and Deputy Programme Leader on Ecosystems at the Environmental Change Institute, University of Oxford, reflects on the field campaign: ‘To me this field campaign was an incredible enriching experience. These were busy days of knowledge exchange. I would be training local students on scientific methodologies, and they were teaching me about the local flora as well as about the local forests and of the Ghanaian culture and traditions.
‘Some forests had taboo days in which we were not allowed to go to the forest and we would use for catching up on lab work. We would also exchange knowledge in other aspects, such as cuisine. I learned to make fufu and I taught them to cook Spanish omelets. Scientifically, I enjoyed training the research assistants in both data collection, data curing and data analyses, and most participants are now co-authors of other related research.’
Image: Part of the team at base camp. © Yadvinder Malhi.
In our study we did not assess on how diversity changes affect ecosystem functioning. However, there is ample evidence showing that decreases in functional, taxonomic and phylogenetic diversity could cause loss of forest functions, such as resources uptake, cycling and biomass production and resilience to a changing climate. Therefore, the ecosystem functions of communities that show decreases across all three facets of diversity could be especially vulnerable under a drying climate.
Overall, our study found that drier forest communities have undergone biodiversity homogenisation due to a warming and drying climate, which could ultimately have negative impacts not only on the functioning of ecosystems but also on their contribution to people’s wellbeing and livelihoods.
Image: Heading into the field. © Yadvinder Malhi.
The work was funded through a European Research Council Advanced Investigator Grant to Prof Yadvinder Malhi, coupled with a Royal Society Africa Capacity Building Award. The transects of field sites where this work was conducted were established with the support of a NERC Standard Grant.
Citation: Aguirre-Gutiérrez, J., Malhi, Y., Lewis, S.L. et al. Long-term droughts may drive drier tropical forests towards increased functional, taxonomic and phylogenetic homogeneity. Nat Commun 11, 3346 (2020). https://doi.org/10.1038/s41467-020-16973-4
A collaboration between Oxford scientists and a distillery has produced a special gin called Physic Gin. Based on 25 ingredients found in the Oxford Botanic Garden, the history of this new spirit stretches back 400 years to the garden’s creation in 1621. With this week’s reopening of the Oxford Botanic Garden following months of closure during lockdown, it would seem there are several reasons to raise a glass.
Oxford Sparks’ caught up with Professor Simon Hiscock, Director of the Oxford Botanic Garden for their latest podcast. He tells Sparks how he came up with the idea for Physic Gin from the moment he started in his new role. He says: ‘I wanted to commission a gin because of the great botanicals we have here and the history of the garden.
The intention was for it to grow herbal, medicinal plants, that would then be used in the teaching of herbal medicine for the medical students of Oxford. Gin was also a medicine in its own right, created in the 17th century in Holland and Belgium, for the treatment of fever.
‘The garden was founded in 1621 by Henry Danvers, 1st Earl of Danby, but it wasn’t planted up until the 1640s. Jacob Bobart, the garden’s first director, was an excellent gardener and also ran The Greyhound Tavern just across the road from the Botanic Garden. He started planting the garden and by 1648 he had about 1600 plants here and he made a list – a Catalogus Plantarum – almost like a field notebook, and this little notebook is the inspiration for Physic Gin. Among those 1600 plants are many botanicals that we would use to flavour gin today and importantly juniper because juniper is the base fruit ingredient for flavouring the alcohol.’
The name Physic Gin derives from the fact that the garden was founded originally as a physic garden; a medicinal garden, as Simon explains: ‘The intention was for it to grow herbal, medicinal plants, that would then be used in the teaching of herbal medicine for the medical students of Oxford. Gin was also a medicine in its own right, created in the 17th century in Holland and Belgium, for the treatment of fever.’
After chatting to his local pub landlord about the idea, Simon was put in touch with The Oxford Artisan Distillery, and the collaborative mixing of spirits and minds began.
The team of scientists and distillers worked closely together on the recipe for two months to ensure that that the history of the garden went into the bottle with the optimum flavour preserved.
Francisco says: ‘We are always playing. We use spices, fruits, flowers and fresh herbs. There’s a base distillation and some of the botanicals need to be distilled separately.’
Incredibly, 25 botanicals have gone into the Physic Gin. They have an almost poetic sound when read aloud: ‘Juniper, coriander seed, angelica root, lemon peel, liquorish root, angelica seed, Japanese bitter orange peel, Grapefruit peel, key lime peel, sweet fennel seed, almonds, poppy seed, wild hops, chamomile flower, wormwood, artichoke leaf and bayleaf...’
As we start to emerge from lockdown, it’s now possible to start to explore the sources of these inspirations in person as The Oxford Botanic Garden reopens on 22 June, and for those in need of a medicinal tonic, Physic Gin is available to order now.
We got the ‘green’ in green issues from the chlorophyll in plants. But the botanical world – which drives the planet’s ecosystems – is the Cinderella science, struggling for resources and recognition, struggling even to keep up with the rate of extinction. And there’s a reason for that – or quite a few, says Oxford Professor of Systematic Botany, Robert Scotland.
While arbitrary international targets are set for ‘saving species’, loss is very much a reality in the funding-strapped world of plants. The truth is, plants have been disappearing at the rate of at least two species a year, every year, for the last 250 years (but that’s a very conservative estimate, we don’t really know).
There are a lot of unknowns - and very big numbers - in the world of plants. Of the 370,000 known species of flowering plants, at least half are so poorly known they are almost invisible to any conservation effort
There are a lot of unknowns - and very big numbers - in the world of plants. Of the 370,000 known species of flowering plants on Earth, at least half are so poorly known they are almost invisible to any conservation effort - as fewer than 25% of flowering plants have a conservation assessment. In terms of insects, the situation is even worse: with just one million described species out of an estimated 6 million. To put these numbers in context, altogether there are some 36,000 birds, mammals and butterflies – about which much more is known.
We do know that about 40% of all land has been claimed for agriculture, so the assumption is that many plants and insects have already disappeared. But we do not really know. It is estimated because of this that more than half the plants in the world’s collections are mislabelled. Imagine for a moment, how significant that (big number) is. If 50% of plants in collections have an incorrect name, what does that mean for our understanding of one of the biggest living groups on Earth? And what does it mean for conservation?
Plant taxonomy, the approach that could sort this situation, does not fit into the zeitgeist - science by innovation
The fact is, plant taxonomy, the approach that could sort this situation, does not fit into the zeitgeist - science by innovation. There is innovation in plant science. Professor Scotland’s team embraced all the technological advances available, including DNA and phylogenetic trees – earlier this year to create a door-stopping monograph of Ipomoea ‘morning glories’. But the science, the pain-staking taxonomy of identifying and recording many known specimens in a species and creating a monograph, is unadulterated, hard-core botany. It may not be good TV, but it is fundamental and good science.
No Luddite, when walking his dogs, Professor Scotland enjoys using Google Lens to identify UK plants. ‘The app is often right in context of UK plants that are very well known,’ he says, surprised, although pleased to be able to catch it out. But the Professor stands by the science of monography, carefully cataloguing and classifying plants as the most effective way to bring order to the chaos of the botanical world - and make long-term progress.
It is essential, says Professor Scotland, to get to grips with what is there, before it is possible to save it. But at the moment, given a business-as-usual capacity, recent Oxford research has shown it takes about 100 years to discover a plant species, at the most basic level. From collecting the first specimen of a species, to describing it as new, and then gathering 15 correctly-identified specimens of that species, it can take a century.
According to a research paper from a team including Professor Scotland and Dr Zoe Goodwin of Edinburgh, some 40 years is the initial discovery phase – that’s from when the sample is brought in by a plant collector, to when it is identified by a botanist.
But, such is the lack of capacity in the system for taking this further, it can then be another 60 years before the next stage is completed and the 15 samples are gathered, as supporting evidence. It is a tortuous process. It impedes progress and action, but it is essential to identifying species.
What chance of achieving conservation targets, when there is no accurate inventory of plants? What chance can there be of a completed inventory of plants, when it takes 100 years even to reach a basic understanding of a species?
What chance of achieving conservation targets, when there is no accurate inventory of plants? What chance can there be of a completed inventory of plants, when it takes 100 years even to reach a basic understanding of a species? How can this process be speeded up, when there is little interest or support for monographic taxonomy and no coordinated international policy – and half of collections are mislabelled? The task is simply enormous – and that is before we even get to thinking about conservation and biodiversity.
Targets for climate change are clear and comprehensible. But when it comes to plants, the 2010 targets – for instance, to have conservation assessments for all plants by 2020 - were ‘pie in the sky’, according to Professor Scotland, ‘Well-meaning but out of reach’.
He maintains, ‘The most recent high-profile policy suggestion is to simplify the message, as was done for climate change scientists, where the aim is to limit global warming to two degrees C. The suggested unified biodiversity target is to limit species’ extinctions to 20 species per year for the next 50 years.’
But, a clearly exasperated Professor Scotland says, ‘This target is impossible to implement, given the lack of basic knowledge of the world’s biodiversity
When it comes to plants, the 2010 targets...were ‘pie in the sky’, according to Professor Scotland, ‘Well-meaning but out of reach’
In fact, he says, most of the Convention on Biodiversity (CBD) international targets, from 2010-2020, ‘were doomed to fail’.
In simple terms, Professor Scotland explains, ‘There is no global strategy for sorting out the taxonomy of flowering plants and insects, so understanding the conservation status of many tropical plants and insects is simply not possible....unless you know what is there, how can you save it or monitor its health?’
Professor Scotland is not recommending an unreconstructed return to Victorian botany as a solution to the world’s problems. But, he insists, it is essential to tackle the huge gaps in knowledge before significant global targets can be made.
Why does it matter?
Clearly a cricket fan, he maintains, ‘Taxonomy is a front foot approach [attempting to tackle the issue, rather than taking a reactive approach]. But we are a very long way from any willingness [internationally] to see something worthwhile in this, despite the evidence.’
Much can be learned from the experience of creating the Ipomoea monograph. Although they were following the path of the first monographer, another Scottish-born Oxford botanist, the celebrated Robert Morison, Professor Scotland and the team confronted the very modern reality of the international plants problem. It was clearly a seminal experience.
It is tempting for the team to reflect that not much has changed in the 300+ years since Morison created the world’s first monograph [of the carrot family]. But taxonomy is in some ways more difficult now than in the past, because of the huge number of specimens that now exist, a voluminous messy literature and many names associated with a group (60-70% of published plant names are usually synonyms). Years of effort was needed to identify the many specimens of Ipomoea in collections around the world - many were synonyms, as the same species had been ‘discovered’ and named multiple times.
If you’re attempting to monitor the health of biodiversity and extinction accurately, you need to know what’s there. We’re never going to get to a comprehensive system where we know everything, but we are a very long way from knowing even half of the world's biodiversity in any detail
Professor Scotland maintains, ‘On the one hand there is a huge diversity of plants, which is a great resource for humankind. But it needs sorting out.
‘On the other hand, if you’re attempting to monitor the health of biodiversity and extinction accurately, you need to know what’s there. We’re never going to get to a comprehensive system where we know everything, but we are a very long way from knowing even half of the world's biodiversity in any detail.’
Goodwin et al 2020 How long does it take to discover a species? Systematics and Biodiversity
Wood et al 2020. A foundation monograph of Ipomoea (Convolvulaceae) in the New World 2020, PhytoKeys. 10.3897/phytokeys.143.32821
Muñoz-Rodríguez et al 2019. A taxonomic monograph of Ipomoea integrated across phylogenetic scales. Nature Plants 5, 11, 1136-1144. 10.1038/s41477-019-0535-4
One slogan of the COVID-19 crisis has attracted less publicity than certain others, despite its apparent roaring success. ‘Whatever it takes’ was not aimed at directly at saving lives, but at preserving the economy and the slogan has been (almost) too successful, according to Professor Bige Kahraman of Oxford’s Saïd Business School.
Speaking at the end of last month, the Associate Professor of Finance said that, in mid-March, the Federal Reserve chair, Jerome Powell, let it be known that the US central bank will do – whatever it takes – to keep the markets from going into freefall.
‘That was critical,’ said Professor Kahraman, to what followed – a sustained stock market run, in the face of bad news heaped upon bad news. While appalling economic indicators have emerged, with many economists and politicians warning of the biggest downturn in 300 years or 90 years or 30 years, the markets have gone up and up.
‘It is surprising,’ said Professor Kahraman. ‘From early April, the market just rallied. It was unexpected and it was against expectations. It was only one month after big market falls.’
In late February, the FTSE 100 had been standing at more than 7,000, but, by 12 March, it had crashed more than 24% - some 1,700 points to 5,230 over fears about COVID-19. Similar falls were seen on Wall Street as the Dow Jones average fell some 7,000 points from more than 27,000 to fewer than 20,000.
Professor Kahraman maintained it was Mr Powell’s reassurance that made all the difference. The Fed chair had begun by cutting interest rates – to less than zero. But received a distinctly frosty market response. But the US bank chief then sent a strong signal to the market that the US central bank would do – whatever it takes. And he was soon followed by UK Chancellor Rishi Sunak – with a massive injection of capital into the UK economy and plans to protect jobs with the furlough scheme and businesses with loans.
Investors rushed into the market....To such an extent, it started to get a little out of control. There was a momentum that saw market rises, whatever the bad news
‘Everyone was expecting unemployment to rise,’ said Professor Kahraman. ‘But there was a very strong commitment from major players. [In addition to Chancellor Sunak’s move] In the US, Congress passed a high speed Bill, which saw a $3 trillion bonus for the economy....The Fed started purchasing assets, including even junk bonds and ETFs… As a result, the market did not do what it had done in 2008, despite the bad news.’
What followed next was most unexpected, Professor Kahraman maintained, ’Investors rushed into the market....To such an extent, it started to get a little out of control. There was a momentum that saw market rises, whatever the bad news.’
The markets have crept up steadily ever since Mr Powell’s intervention, so that the index has recovered by more than 15% in the US and the UK – in spite of the dire economic warnings. At the end of May, the FTSE reached more than 6,200, while the Dow Jones went over 25,000 points – on lockdown-easing news.
Another factor in the market optimism, Professor Kahraman said, is that, although there are expected to be some closures, as firms cease trading - others will move into that space, ‘Some firms will fail but others will acquire their business, which will mean market concentration – which is good for profits. If they manage to survive, there could be higher profits for firms in future.’
We don’t have the same structural problems of the Great Depression. Europe was going into a slowdown, but this is an external shock [In the UK and the US] and the recovery should be fast once the treatments and vaccines are developed
And, said Professor Kahraman, ‘Although many industries have suffered a very negative affect, others have been boosted, particularly tech firms. This has been good news for them in terms of business.’
But, she warned, ‘This [longer term government fiscal stimulus packages] is not sustainable.’
Government bail-outs cannot be open-ended. However, Professor Kahraman does not believe we are heading towards a Great Depression-style slowdown.
‘Although some of the figures may resemble the economy around the same time, we don’t have the same structural problems of the Great Depression. Europe was going into a slowdown, but this is an external shock [In the UK and the US] and the recovery should be fast once the treatments and vaccines are developed.’
Eighty five per cent of children around the world in more than 150 countries are affected by school closures due to COVID-19. Many are currently receiving no education. And internationally, the fear is that some, not least girls, will never return to school. While the public health concerns of COVID-19 should, no doubt, be tackled now, policy makers could also act swiftly to avoid the education crisis turning into an education disaster.
Policy makers could also act swiftly to avoid the education crisis turning into an education disaster
No one knows how the virus will wreak havoc in coming months. Will there be a second peak in Europe or China? Will Africa escape the worst of the pandemic? Will the virus be contained in Latin America or South Asia, where it is currently not quite at its peak? The final consequences are fundamentally uncertain.
But this should not stop us acting now. Some potential actions are ‘no-regret’ policies - no one will regret them later and they are a good use of resources now - however the pandemic evolves. Elsewhere, I have expanded on no-regret policies in the areas of public health, social protection, the economy and the manufacturing and distribution of a vaccine when it becomes available. Here, I want to focus on no-regret policies for education, specifically for lower and middle income countries - though they have global relevance.
This blog argues for three areas of no-regret policies:
- First, ensuring learning continues to happen in whatever form is possible;
- Second, that special actions are prepared for remedial action and reversing dropout later; and
- Third, learning the lessons from digital education, in order to move towards a more inclusive and effective digital learning system later, even in resource-constrained countries.
COVID-19 could not have come at a worse time for children. It is generally acknowledged that there is a serious learning crisis in the developing world. While enrolment has increased to historically unprecedented rates, too few children are learning. For example, a recent World Bank report highlighted that three out of four children in grade 3 in Kenya, Tanzania and Uganda cannot read a sentence such as, ‘the name of the dog is puppy’. In India, by grade 3, three-quarters of children cannot solve 46 minus 17, and by grade 5, it is still a problem for half of them.
Abhijeet Singh, an Oxford DPhil, now at Stockholm School of Economics, has shown that pupils typically start at similar levels, but then some fall behind, never to catch up, in the kind of school systems we find across these countries. And now, children who were especially at risk of falling behind, have lost their access to school because of COVID-19. Often, such children are from disadvantaged families – and now they have to learn at home, if at all.
Children who were especially at risk of falling behind, have lost their access to school because of COVID-19
The first no-regret policy should be to try to keep children learning now, as much as we can. Some are at risk of falling behind in the way Dr Singh has shown - and catching up never quite happens in the educational systems of the developing world. And the signs are not good. Work by the Centre for Global Development found that 95% of children, currently at home in Senegal, were not given any work by teachers, while 30% were not involved in anything educational. Supporting learning by any means available is essential – digitally, via radio or TV, via homework distributed to children’s houses, community workers identifying children vulnerable to lose out and more.
The second no-regret policy should be to prepare now to ensure children are identified and targeted for remedial education, or to reverse drop-out later. Children will be behind, but some will be more behind than others. This is the time to plan for better forms of remedial teaching, such as the type of programmes pioneered by Pratham in India, and in recent years across the world. Evidence of their potential at scale is strong as joint work, including with the RISE programme and others at Blavatnik School of Government at Oxford, have shown.
There is another reason why it is important to do this now. Much evidence exists to show that, during economic hardship, children will not just temporarily leave school, but do so permanently. And this is likely to happen now too. This affects, not least girls - with early marriage one of the consequences. It is the time to consider how such children, who may intend to drop out, can be reached. Maybe conditional cash transfers, targeted at adolescent girls, could be considered, whereby cash is offered to families conditional on children doing homework - which will continue after schools reopen, if children continue to attend.
Much evidence exists to show that, during economic hardship, children will not just temporarily leave school, but do so permanently. And this is likely to happen now too
The third no-regret policy concerns digital learning: this may well be its time. But, unless we start acting now, this will be the start of more learning inequalities rather than fewer in the future.
All over the world, the scale of digital teaching and learning has exploded, with countries and schools looking for ways to connect to pupils. Crucially, though, there are huge inequalities of access within countries - and between them. This was highlighted by a report we did at Blavatnik School of Government - as at least three billion people remain digitally unconnected.
No doubt, the appetite for digital learning will be increased by this crisis. And doing this as well as we can is a first step. But if we do not start attacking digital inequalities through inclusive access, and prepare now to roll out at scale across the world, educational inequalities will continue to expand ever more. Work on a Digital Roadmap and Digital Toolkits may help policy makers get ahead. But there is more. The way digital tools, such as Zoom, Teams, Skype and the like, have been used for education all over the world is only exploiting their communication opportunities.
Digital learning systems are very different. If used well, they allow low-cost individualised learning at the right level with feedback loops to suit each child, rather than exposure to the same for all children in a ‘Zoom’ class. This has substantial potential in low-resource environments. A recent report by a team I led at Oxford gives more ideas. The key now is to learn as much as we can from the digital experiences during the crisis, and then get educational systems ready to using digital tools in the future in an inclusive way.
The developing world faces a learning crisis...We do not have to wait until after the COVID-19 virus has passed to start tackling it. Nobody will regret acting now
The developing world faces a learning crisis, exacerbated by the COVID-19 pandemic. We do not have to wait until after the COVID-19 virus has passed to start tackling it. Nobody will regret acting now. And it will make responding later easier - and more affordable.
Professor Stefan Dercon
University of Oxford (Blavatnik School of Government and Economics Department)
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