Why soil is vital to life | 91TV
Transcript
- Thanks so much for that lovely introduction and thanks so much to the Royal Society for
- inviting me to give this lecture. It is such an honour and thanks to everybody who's come to see
- the talk. Thanks to the people who nominated me at Durham University and the referees. Um,
- I'm looking forward to telling you today about soil and then a little bit about the role of
- women in rebuilding soils. First of all, I just want to say a little bit about the situation we
- find ourselves in with regards to soil and climate change. We're in what we would call
- a vicious cycle where, for many years now, since industrialization, we've been - in fact, probably
- since the start of the Haber-Bosch process, we've been having industrialised agriculture,
- where really we haven't been managing our soils for soil health. So we have poor soil management,
- which has, in part, contributed to climate change. Of course, fossil fuel use is the
- biggest cause of emissions causing climate change, but these two things coupled together,
- poor soil management and climate change, are putting us in this vicious soil climate cycle.
- So the poor soil management, climate change is leading to poorer soil health,
- which means the soils can't hold on to carbon. That release of carbon, coupled with the fact
- that we have greater reliance on agrichemicals for our agriculture, means that we've got more climate
- change, and that climate change, of course, includes extreme wetting and drying sequences,
- flooding and drought, and even the fires that we've seen, and that's causing more
- soil degradation. I think the important point thing from this slide is a saying that is famous
- in Zimbabwe. Some of my colleagues in Zimbabwe, Paul Mapfumo, Tariro Gwandu, talk about the fact
- that poor soils make poor people, and poor people make poorer soils, and we're in this
- vicious cycle. So whether it is flooding and the water erosion that happens because of flooding,
- we've got poor soils, the soils are washed away, or whether it's drought on the right-hand side we
- have here. Effects like the Dust Bowl that Roosevelt was talking about when he came
- up with his saying, 'A nation that destroys its soils destroys itself.' We are losing our soils,
- and the estimates for how much soil we're losing each year are gross underestimates, coupled with
- the fact that we're actually landfilling about 100 million tonnes of clean subsoils
- every year. We're not looking after our soils. So let's take a step back. I want to think about
- where soils have come from and think a little bit about evolution. Now, I'm not a biologist;
- I'm an environmental engineer. I started off in the water industry, and then I moved into
- soil health. When I saw what a state our soils were in, I was very passionate about trying to
- educate people about the fact that soil is living and soil is linked to climate change,
- but when I was at school, it wasn't six kingdoms, I don't think, I think it was five kingdoms. We
- certainly had the animals, the plants and the fungi, and I think the protists and bacteria,
- but we didn't have archaea and bacteria. If we look at the balance of species on earth,
- we can see that most of this tree, which is representing life since the evolution of life,
- is basically bacteria and archaea, those two kingdoms that we can't see,
- and even within the eukaryotes, which are the things that have got nuclei and organelles in
- their cells, as opposed to no nucleus in the prokaryotes of the bacteria and the archaea,
- even within the eukaryotes, that's mainly fungi. There's a few animals and a few plants, and then
- when we look at where people are, that tiny little red bauble that's hanging off the tree is mammals,
- and we are a tiny fraction of that. So if we look at the diversity of life on planet earth, it's
- estimated that over 99.99 per cent of microbial species, which includes all of these bacteria,
- archaea, and in fact some of the eukaryotes, the protists, things that we can't see,
- and the fungi - that's what microbial means, it means things that we need a microscope to see
- are unknown to science - are unknown to science, and all of those things, pretty much, are in the
- soil. So 99.99 per cent of microbes are unknown to science, and they're in the soil. It's a vast
- reservoir of unexplored potential, which is really exciting for human health and wealth. So again,
- taking a step back, who's actually in charge here in terms of soil health, and who's in charge in
- terms of planetary health? Well, of course, we think that it's us who's in charge, and we are
- doing quite a good job of doing a bad job, as it were, of planetary health, as we know, but we only
- evolved about 7 million years ago, so in terms of the planet's age being 4.5 billion years old
- roughly, and life having evolved about 3.7 billion years ago, we haven't been around for very long.
- So in terms of that knowledge within the DNA and that adaptation of life, who's in charge? Well,
- 1.5 billion years ago is when plants evolved. Three-point-five billion years ago is when we
- had roughly the split between bacteria and archaea and eukaryotes. So it's that microbial life which
- evolved first, and it's that microbial life which is in the soil. We can define what a soil is,
- but basically I'm defining it as organic matter and rock which can hold on to water. the organic
- matter can hold on to water. If we look at it with that definition, we can say that soils first
- evolved in some form at least 3 billion years ago. So soils have been around a lot longer than us,
- and soils are living. If there's one message that you go home with tonight, it's the fact
- that soils are living. We carried out a survey of 4000 children about three years ago now,
- and those kids didn't know that soil was living. I don't mean living things are in the soil,
- worms and spring tails, etc. Those are in the soil. A lot of kids know that,
- a lot of adults know that, but kids don't know that actually the soil material is living.
- That's not a surprise that they don't know it, because I'm sure many of you didn't know that
- unless you're gardeners or particularly interested in that area.. They don't know it because we're
- not teaching them it at school. That's why I'm so excited to have the funding from the Royal
- Society to develop materials to teach kids one of those main outcomes that we learned about in this
- survey, that soils are living. The other message that kids didn't get, and these kids were aged 14
- to 15, was that soils are linked to climate change. So if we look at the UN Sustainable
- Development Goals, we can see that we've got 17 goals. There's quite a lot of research showing
- that soil health, in many ways, underpins all of these goals, but the key to sustainable
- development goals that are very definitely linked in that vicious cycle that I talked about in my
- first slide, of climate change and terrestrial ecosystems, soil health and biodiversity and
- understanding that link is absolutely essential for Generation Z and Generation Alpha. It's
- essential for all generations, but they're the generations that are being left with
- fewer natural resources, as we call them, than we inherited, because we're not living sustainably.
- I think this slide is usually attributed to kick-starting or certainly quickening
- the environmental movement of the 60s and 70s. So the Apollo missions in '69,
- when we landed on the moon and looked back and saw planet earth, and saw the thin blue line
- and realised how fragile our planet was, and the fact that we only have a small atmosphere, we only
- have this critical zone of soil, which is keeping us alive in our terrestrial ecosystems, was very
- prescient. We know now that soil is living. I'm going to go into a little bit more detail about
- a paper that blew my mind when I read it in 2020. We've been doing a lot of work in the Department
- of Engineering at Durham University on adding minerals and organic matter to degraded soils in
- order to improve their health, and I put health in inverted commas just as I would for human health,
- because it's quite difficult to define health. It is a complicated word to define. This paper
- was written by somebody in the audience. It was written by Andy Neal and John Crawford and lots
- of other authors, and it has a title which is a little bit off-putting. I think I was
- recommended to read it by somebody who had read it and understood it. Soil as an extended composite
- phenotype of the microbial metagenome. I'm going to attempt to translate it into layperson-speak,
- which is what I needed to do in order to understand it, because I'm not a biologist.
- So soil is an extended composite phenotype. What does that actually mean? If I was to show you a
- picture of a bird's nest and tell you that the scale on this is centimetres, you might know that
- this bird's nest is a wren's nest, and if you were a birder, you might know that this bigger nest,
- which you can see the scale of because it's a big nest in a tree, is an eagle's nest,
- but you wouldn't have to be a birder and an expert in bird identification to see that it was a small
- bird and a big bird. Those nests are the birds' extended composite phenotype. They have changed
- their environment through their genetics, so the equivalent might be a beaver making a dam.
- It's an ecological engineer, and of course humans are ecological engineers. In fact, our extended
- composite phenotype, or one of them, is our house. We build houses, and we have done that in order to
- provide shelter and warmth. If we've got air conditioning, which is becoming increasingly
- important in some countries, then we've done it in order to control temperature and also
- access to oxygen, let the carbon dioxide, etc. So this is an extended composite phenotype for
- humans, also known as our home. The point I want to make is that soil's extended composite
- phenotype is, or rather soil is, the extended composite phenotype of the soil microbiome. So
- all those fungi and bacteria that are living in the soil are actually making the soil. Soil
- is composed of minerals, so things like silica dioxide, sand, iron oxide, manganese oxide. These
- minerals are in the soil with organic matter and air and water. Four things make up soil,
- but if you had a pile of organic material, minerals, air and water, it wouldn't be
- soil if it was sterile, if it didn't have the living things in it, because the living things,
- the microbe, the microbiome, which consist of all the different things that I've mentioned,
- fungi and bacteria, etc., are actually exuding chemicals, extra polymeric substances which
- stick together the sand, the silt, and the clay into the exact construction that that
- soil microbiome wants in order to provide the home, the shelter, the provision of oxygen
- and carbon dioxide release, etc., that it wants. Okay, so I'm anthropomorphizing quite a lot here,
- and I make no apologies for it. This is a picture, not my picture, of a soil aggregate. In the middle
- here, we have a grey blob. That's a piece of soil that is probably a quarter of a millimetre
- across. It's a macroaggregate, and it's made up of mineral, organic air and water. We can see a
- close up of some of the fungi and the bacteria and a smaller microaggregate here and a bit of
- stick. So if we were to actually cut that in two and look at what is inside of that soil aggregate,
- we would see a distribution of channels that is the porosity within that macroaggregate, little
- channels that allow air and water to get to the microbiome. The microbiome is represented by the
- red bits, and the yellow by the blue bits, and you can see that the red bits are towards the centre.
- That's the anaerobic bacteria who don't want to be living in the presence of oxygen, so they hide
- away in the middle of the microaggregate, living on the microbial, on the mineral surface, just
- like we live on the surface of the earth, because we don't want to be swimming around in the water.
- We want to be attached to a surface and grounded. You can see that at the edge of the
- macroaggregate, which is nearer the larger pores, then we've got more oxygen coming in, so we have
- this macroaggregate constructed literally from the glue that the microbiome is excreting,
- to create the exquisite structure that it wants as its home. So the extended composite phenotype
- that is soil is also known as a microbiome home. If we have compaction - and nobody was
- hurt in this hurricane, I think it was, it was quite difficult actually to find an image where
- nobody was hurt - then obviously we don't have a home anymore. This is what we've done to soil.
- We have not had good soil management, we have compacted soil, so that air and water can't get
- into the soil. We have also used pesticides which kill certain bugs, and we, of course,
- thought we were feeding the world, and we did feed the world, but we sleepwalked into a situation
- where we have damaged the soil to the point that it is not soil anymore. It's pretty much inert,
- which is how we've treated it all along. Some people, of course, knew about this and have been
- shouting from the rooftops for some time about the fact that we've been damaging soil in this way. I
- think everybody is waking up now and regenerative agriculture has got a lot of support now from
- industry, as well as some support from government. So we've been overusing pesticide, which is not
- just killing some of the pests that we wanted to kill that were destroying our crops, monocultures
- which don't work very well in harmony with soil health, but we've also been killing some of that
- microbiome, which is actually what creates soil, as we know. The problem with killing some of the
- microbiome is that we're destroying the soil plant symbiotic relationship. The plant soil
- symbiotic relationship is that plants are the photosynthesizers. They are the organisms that
- can create sugar from the sun's rays and carbon dioxide and water, and they transfer up to about
- 40 to 50 per cent of that glucose through their root system into the soil, via the fungal hyphae,
- via the mycelium. They are feeding the mycelium, they're feeding certain microbes in exchange for
- the mycelium and the microbes going to the rocks, the minerals in the soil, and extracting the
- nutrients that you can't get from the air, so the macronutrients and the micronutrients, calcium,
- magnesium, and potassium and nitrogen, and the micro micronutrients like zinc and selenium.
- So you might think, well, what's the problem with pesticides. We've talked about that's killing some
- of the soil microorganisms. The problem with overuse of chemical fertilisers is that we're
- destroying this soil plant symbiosis. If we feed the plant directly chemical nitrogen, phosphorus,
- and potassium, which is what we've done, then the plant doesn't have to have that relationship with
- the soil microbiome anymore. It can stop feeding the soil microbiome. If you stop feeding the soil
- microbiome, it's not going to go away and starve. It will eat the glue that is holding together your
- sand and silt and clay, and that is why we have exacerbated soil degradation with poor management
- of soil by overusing chemical fertilisers. I'm going to present some work now which is very new,
- by someone in the audience, Doctor Stephen Chivasa from Durham University, which is quite exciting,
- showing that there's another element here as well, because we are all really plantophiles
- and we don't generally, until we get to sort of middle age, think that soil is very exciting.
- We are very much attributed plants as being in charge of soil. There's evidence coming out now
- that actually it is a two-way relationship, as we know, and in some cases it's actually the soil
- microbiome which is in charge of the plants, so it's a two-way relationship, but what you
- see here on the left is cowpea plant, which is a bit like a chickpea, from sub-Saharan Africa,
- which is growing in a soil which has got an active microbiome. On the right-hand side,
- we've got a soil where the microbiome isn't alive anymore, and these two plants were subjected to
- drought. So this is a very common stress in many arable systems, but particularly in sub-Saharan
- Africa. If we see what's happened, we can see that the microbiome, we think there's a correlation
- between having an active microbiome and the plant surviving drought for a bit longer. If
- we actually look at the expression of a marker gene, which is responsible for signalling that
- the plant is undergoing drought stress, we see when there's an active microbiome, on the left
- here. We see less of the expression of this gene, which says the plant is suffering from stress, and
- stress is not good for plants, just not like it's not good for us, or too much stress is not good.
- The dead microbiome, we see more stress in the plant. It's not as resilient because it doesn't
- have that symbiotic and supportive relationship with the soil microbiome. So this is providing
- further evidence for the importance of soil health in crop productivity, in food sovereignty,
- understanding the relationship, not just of the plant microbiome, but how it interacts with the
- soil microbiome. So what is a healthy living soil? Well, we put a definition, and this was Andy Neal
- from Rothamsted who put this definition in our paper that we published in 2022,
- which was called ,A nation that rebuilds its soil, rebuilds itself. A healthy soil microbiome
- is one that maintains a high diversity of functions across a range of organisms,
- having as broad a range of traits as possible. So some might be good at helping the plant
- with drought resilience, some might be good at storing carbon, some might be good at nitrogen
- stabilisation or pollutant immobilisation, all sorts of different ecosystem services.
- I tried to look for a definition of healthy gut microbiome, and I'm really interested
- in healthy gut microbiome, because I'm following the science. It's a little bit further ahead than
- the soil microbiome work. I couldn't really find one, and that's because it's difficult to define,
- so I was really excited that Andy Neal would put his name to a definition, which I think
- is a pretty good one. The parallel between our gut microbiome and the soil microbiome is
- important, because we evolved to be connected to ecosystems, and we evolved to eat a bit of soil,
- to be perfectly honest. So you are what you eat, and so is soil, and the microbiome is important
- to both. If we think about humans, we need 5 a day - or is it 30 a week now, 30 different
- colours? - and that's diversity. That's what soil needs. The monoculture system that we have
- developed since industrialised agriculture to suit economic systems, and the reduced variety
- of plants that we depend on in today's society because of globalised markets, is not good for
- soil health. In the same way as if we only ate five food types, it wouldn't be good for our gut
- microbiome. So the diversity that we need in our gut microbiome, soil also needs that diversity.
- You need macro and micronutrients, so does soil, and actually, if in working to rebuild
- soils and replacing minerals and organic matter that soils might be missing, because
- we've canalised our rivers, and we no longer return anything other than chemical nitrogen,
- phosphorus, and potassium to the soil, if we return it to the soil, and we grow plants from
- a soil that has access to all of those micro and macronutrients, we have a much more equal society
- where everybody has access. They don't have to go to Boots, if they can't afford to go to Boots,
- to get their macro and micronutrients. They can get it from their diet. You need the right balance
- of oxygen and carbon dioxide and other gases, and so does soil, and you can't operate without water,
- and neither can soil. Your ability to function is affected by herbicide and pesticide use,
- and the broken nature of our food system is that we are seeing these residues in our food. There's
- less of it in organic food. If we see it in when we eat it, it is having an effect on our health,
- on our microbiome, in the same way as it has an effect on the soil microbiome.
- There's a lot of excitement about probiotics, and I think probiotics is a very exciting area,
- but my colleague, Tom Curtis, who's also in the audience, would tell me that everything
- is everywhere and the environment selects. There's no point in taking probiotics if you're sat on the
- sofa eating hamburgers and you never exercise. You need to have the right environment in your
- body in order to facilitate the microbiome that is there, or there in small parts,
- to flourish and help you with your human health, just like in soil health. This is
- what we're trying to do as engineers working with soil scientists and social scientists, is to look
- at the environment of the soil. If it's compacted, what needs to be added in order to decompact it,
- what minerals might be missing chemically, what particle sizes might be missing that we can add
- alongside organic matter, in order to create the right environment for the microbiome to flourish,
- because it is the microbiome which is providing the ecosystem services like water storage,
- carbon storage, the micronutrient content of our crops that we need to support.
- So there's a growing interest in the microbiome one-health concept, which is that the microbiome
- health is underpinning and interconnecting systems across the planet, and it is underpinning plant
- health, like I showed you with Doctor Chivasa's work, and animal health we know is dependent on
- plant health. Either you're a vegetarian or you eat vegetarians. We're all dependent on plants,
- and that is underpinning planetary health for us and for all the other species that live on
- this planet. So what can an engineer do? Why has engineering got anything to do with this? Well,
- first of all, I've been interested in soils from an engineering point of view because we absolutely
- have trashed our urban soils. We haven't thought about the ecosystem service provision that they
- can provide the water storage, the carbon storage, the health benefits. We're starting to think about
- that, but we need to do a lot more in that result, but in agriculture as well, all of the soil that
- humans have anything to do with is, basically, engineered. It's an engineered living material,
- struggling to live in some cases, but it is an engineered living material.
- So engineers think about systems in terms of inputs and outputs, and I actually think this
- is a very useful way to think about soils. Soils, just like any system, including human bodies, need
- material inputs and they need energy inputs. What they're using those material inputs and energy
- inputs for is to provide some services. So in order to provide those services, we need a healthy
- environment, as we've talked about. We have coming out of that production process of the services
- that we're going to see in the next click of this. We have some waste emissions, like we always do,
- in any process. Those gaseous wastes and aqueous and solid wastes, just like humans produce,
- are actually very important for planetary health. So the gaseous wastes are the carbon dioxide,
- the methane, the oxygen that is produced through microbial processes and through plant processes
- that are supported by the microbiome. This is controlling global biogeochemical cycles.
- The aqueous waste, the solid waste, they are sticking the soil together and providing the
- organic matter for our aqueous systems. The outcome of this system of terrestrial ecosystems
- is the services that we all require in order to survive that we tend to take for granted.
- The nutrition, food security, the health, human health, not just the nutritional content of food,
- but also the physical contact with soil. There's many studies now coming out that show that that's
- important for our microbiomes to be connected, and also the mental health benefits of being out in
- green spaces that we're beginning to understand a bit better. Of course, for the microbiome,
- it's building this house, also known as soil, for thermal comfort, etc., because it's doing
- it for the microbiome community, but it's also for us. So those energy inputs are relatively
- straightforward. It's not what we're doing at the minute. We have monocultures of maize and
- wheat around the world that is not great for soil health. If we had more diverse cropping,
- then we've got the give a day that we're aiming towards for a human health diet. That's what we
- need to aim towards nominally for a soil health diet as well. We need diverse cropping systems.
- For energy, it's relatively straightforward. Diverse cropping, the carbon is the energy source,
- it's brought in through photosynthesis. The more difficult bit with today's society, and why we
- believe that we need to rebuild soils proactively in order to reverse decades of soil degradation,
- is putting the material inputs in. So this is the organic matter that organic farming has been
- promoting for decades, and any gardener knows that organic matter should be returned to the soil. We
- believe that it should be returned with minerals, with redox active minerals, things like iron
- oxide and manganese oxide. These are often waste materials in today's society that are currently
- coming from the water industry, coming from other industries, and landfilled as useless wastes, when
- in fact, they're part of soil's system of circular economy of inputs and outputs, and should,
- as long as they're clean, be returned to the land. The reason why we're so excited about returning
- the minerals at the same time as the organic matter, is because, if we look at these images
- that I've just put up, these are transmission electron micrographs, which means that you use
- electrons to look through minerals, and we can see on the left-hand side here, some plate-y clay
- minerals. I call them plate-y because they're kind of table-shaped. They're layered minerals.
- The black railway track lines on there are the iron oxides and manganese oxides that are
- attracted to clay minerals. Remember, I said that soil is made up of minerals and organic
- matter and air and water. The second TEM image is beautiful. It's actually a piece of organic
- matter. So organic matter, what I mean by organic, it's made of carbon, hydrogen and oxygen, and with
- TEM you can see these are very small, if you look at the scale. That's 50 nanometres. These little
- bits of organic matter that are in water, they're little bits of soil, little bits of crud floating
- along in the water, and you can see, again, the iron oxide stuck in the organic matter. Iron
- oxide sticks to organic matter, sticks to clay. This is the architecture of soil. This is how it
- sticks together, organic matter sticks the iron oxides and the clays together. This is a paper
- published by one of my colleagues in the audience that I was involved with. This took a long time
- to come to fruition. Professor Caroline Peacock and her team, and myself, have been working on
- the idea of the soil mineral carbon pump for some time. It took a long time to get to come to press.
- There's three types of pumps that we talk about now. There's the biological carbon pump,
- which is photosynthesis, pulling carbon into the soil, there is the microbial carbon pump,
- which is when microbes breed, and there's more microbial biomass in the soil, called necromass.
- That's the microbial carbon pump, and the mineral carbon pump is when minerals actually stabilise
- the organic matter. The organic matter is so tightly stuck to the mineral surface that it's
- not really readily accessible as a food source for the microbiome. So it can be stored in the soil,
- taken out of the atmosphere, and help us towards our net zero trajectory. About 10%
- of emissions come from the land, emissions of carbon dioxide equivalents, so we can put a
- bit back in the ground if we start to rebuild it. So that's what our work is about at Durham
- University, and working with many partners with Rothamsted, with Glasgow, with York, Newcastle.
- We're looking at SMART soil. SMART stands for soil microbiome augmentation and restoration
- technologies, and we're very proud that Durham University has invested 1.7 million pounds,
- and partners in the audience have invested money as well, to consolidate leadership in
- soil microbiome at Durham University, because Durham University believes that this is a very
- important area. Soil is currently worth about £100 a tonne, and oil about £500 a tonne. I think
- that's going to change in the next few decades. It's going to swap the other way around. I think
- there are some countries in the Middle East that are selling soil for an awful lot of money,
- because they haven't got any healthy soil, and it's going to become a big a big issue for many
- countries. It already is. So it's called SMART because we are we're putting the carbon and the
- minerals back into the soil, but we're optimising how we put these carbon and minerals back into
- the soil, by using a digital innovation, by using AI in order to collect data sets.
- AI is already used, excitingly, to predict soil health. We have probes. Some of our partners in
- the audience have developed soil health probes, Enable, that you can put into the ground,
- it can measure certain parameters, conductivity, pH, and potassium,
- etc., and it can learn about soil health, water content, etc. What we're doing in this project,
- is we're trying to optimise the right level of minerals and organic matter to put into degraded
- soils, in order to work with local communities and deliver the ecosystem services that they want to,
- whether that be net biodiversity gain, carbon storage, or water storage,
- and if you put the carbon and the minerals into the soil, then the water will follow.
- So now onto the role of women. Now, I did find that when I sent the invites out to people,
- I had a few - more than a few - more than a handful of blokes saying, 'Oh, maybe I should
- give this spot to a woman, if it's about women's rights.' It's not about that. It's about the
- fact that largely in today's society, women are assigned caring roles and I could have found many
- images online which showed pictures of women kneeling next to wheelchairs in caring roles,
- and I chose not to use one of those images. The image I wanted to use was this book,
- which I have recently bought and enjoyed reading called the Care Manifesto published by some
- colleagues of my friend in the audience, and they use a phrase, they talk about the politics of
- interdependence and the fact that things are all interconnected, as we know, but that we've got to
- start having politics that is more interconnected. I don't want to talk about politics even though
- I've got a political image coming up, but the phrase that they use is that carelessness reigns
- in our world. This is the first sentence, and it very much resonates with me. We don't teach any
- children at school to care for things. We teach children about the rules, we teach them about
- the facts. This is what we want to do with the Royal Society funds that we've been given in the
- Rosalind Franklin Award, because we desperately need more women to be in leadership positions.
- We can see from last week - I thought that this was a relevant image, but so much has
- happened politically this week, since then - the lack of female perspective during COVID was one
- of the issues that has been highlighted by the COVID inquiry, and if we look at the statistics,
- I don't know whether you can see these statistics, if I pick a few out. The reason why I put this up
- is because agriculture here has 23 per cent female leaders. There's plenty of women in agriculture
- and soil, but there's not enough leadership. If we actually look, sticking on politics,
- I was a bit surprised at this figure that in the public sector and government, we have
- 40 per cent of women leaders, and then I looked up some stats of the Cabinet. It's 20 per cent over
- the last 20 years. So the senior leadership figures are not women. We're not saying that
- women provide better management. What I'm saying is that we need those diverse perspectives and
- different opinions. That's where the role of EDI comes in, in terms of creativity and innovation
- and scrutiny. Most importantly, scrutiny. So we desperately need more women leaders. If
- we look towards engineering, I feel, personally, having been involved in engineering for over 20
- years now, that the figures haven't changed, in terms of undergraduate courses. This is
- just talking to Jo, the leader of EDI here at the Royal Society. This is a cultural issue. In
- some countries, there are more female engineers. These are difficult challenges because culture
- is a difficult thing to address, and we keep trying. There's amazing organisations like Women's
- Engineering Society, and the Royal Society, trying to change things, like supporting the
- Rosalind Franklin Award, for people like myself to work with children in STEM. So a little bit about,
- in the final few minutes, what we want to do with the funding that we've been awarded. We're working
- with - and Joanne couldn't be here tonight - but Joanne Appleby is the CEO of this amazing
- organisation, OASES, Outdoor and Sustainability Education Specialists. They work with primary
- school and secondary school children, and have been doing for 25 years now, taking them outside,
- teaching them to get their hands dirty, teaching them about sustainability and climate change.
- Basically, we want to follow up on the survey work that we've done with those kids. We know
- kids don't know that soil is living. We know kids don't know that soil and climate change
- are linked. so we want to teach and work with Gen Z and Generation Alpha. We want to teach
- them to care for the soil, and that's where the role of women comes in, because as I say,
- women are largely assigned this caring role. We want to make sure that education includes care. So
- we've tried in other ways. We've created lots of different animations, to engage people with soil,
- but there's too much out there in the internet. We need to produce materials that are useful to
- teachers, and that's what we want to do. One of the things that we want to do is work with
- kids to produce - we've done this - to produce terrariums. So this is a terrarium from my house.
- A terrarium is, basically, a sealed container of soil and plants, and it's basically like
- a mini earth. It's like a little biosphere, because it's materially closed, which means
- that oxygen and other gases can't get in and out, but it is energetically open, which means
- the sunshine can get in and so the plants can photosynthesize. So it has its own water cycle,
- its own carbon cycle, its own nitrogen cycle. From a scientist's point of view, it's amazing,
- because you can count the carbon atoms, you can count the nitrogen atoms, if you want to. From a
- kid's point of view, it's amazing and actually adults like it as well, because you get your
- hands dirty, and it teaches you how to care for the soil, and the importance of the soil,
- so I'll leave that at the entrance for people to look at it on the way out. So we're going to be
- Teaching Gen Z to build terrariums. Terrariums are commonly used for climate-change teaching,
- but unfortunately a lot of the resources actually talk about using sterile soil,
- which just, it says everything about the fact that we're scared of soil and scared of microbiome,
- when in fact we should be embracing it, if it's a clean soil. You know, kids should be getting their
- hands dirty. We're also going to be, excitingly, burying underpants. Now, some of you know about
- soil, probably know about this. This is not my idea. This has been around a long time, and many
- people have used it, but it's very engaging. You take a big pair of white cotton underpants
- and you put them in the soil. The pants on the left are from a soil that is not as healthy as
- the field where the pants on the right have been buried. That's because these pants are made of
- cotton, and cotton is made of carbon, hydrogen and oxygen, and it's a food for the microbiome.
- So if it's not being fed enough through the diverse planting that we should have, then the
- underpants will serve as a food source. So you can monitor soil health in these practical ways
- that is very engaging for kids to understand that it is living and it is eating their pants. I want
- to end by on a hopeful note, talking about how I really believe that we can get to a virtuous soil
- climate circle. If society works with the soil microbiome instead of against the soil microbiome,
- if we consider the material and energy inputs that the microbiome needs, then we can return
- wastes that are suitable, optimised for that microbiome of organic and mineral materials,
- to our soils, and work with communities to provide locality-specific ecosystem service
- provision. So that means carbon storage, water storage, net biodiversity gain. It's
- not a panacea. There's a trade-off to be had with these things, but the discussion needs to be had.
- Communities will benefit, particularly from communities renegotiating their relationship
- with the land in some cases, because our system is a bit broken. I think everybody knows that.
- There are some communities who don't have access to land. They don't go out and engage with nature.
- All of this needs to be taken into account. This is not just engineers and soil scientists,
- it's social scientists, anthropologists, economists, legal academics that are
- involved in this work. Then, that is going to help society to work with the soil microbiome
- and the co-benefits that that brings for mental health, for economic prosperity, is something
- that is another co-benefit, I believe, in terms of if we have soil at the heart of the circular
- economy. My colleague in the audience has told me that in a tonne of soil there are 10-to-the-13,
- which means 10 with 13 zeros after it, microbes in the soil, so individual cells, and because soil,
- in general, if it's a stable system, a healthy soil, the birth rate equals the death rate, again,
- anthropomorphizing, then, then that means that there's 10-to-the-13 microbes born every day.
- One in 300 of those microbes born every day will have a mutation. Now a mutation is where you get
- the new chemicals, the new bio-based resources, the new antibiotics, the new cancer cure. We
- talk about the Amazon being home to lots of cures for cancer, etc. The soil is also host
- to a huge number of organic resources that we can involve in our green economy and create a new type
- of circular economy with natural ecosystems at the heart. So it just ends for me to say,
- thanks so much to all the inspiring people that I work with, and if your picture isn't up here,
- it's not that I don't find you inspiring, but these are the people that I have developed
- ideas with and have been very inspirational to me through my time at Durham University, and,
- of course ,thanks to all the funders as well, for supporting me with the work that I do.
- So, thank you, Karen. What a wonderful talk. A fantastic combination of really interesting
- science and a very important subject. I, for one, have learned a great deal. Now,
- we will have some questions from the audience, and maybe some questions from online as well.
- I'd like to start with some questions from the audience, if there are any. The one
- right at the front, yes? Can you speak in the microphone, please? Thank you.
- Oh, thank you, Karen. You've really movingly expressed the plight of our
- soil. I still live in Cambridge and a long time ago, someone told me,
- if we didn't de-intensify our agriculture on the fens, the fens would disintegrate and blow away,
- and that hasn't happened, but I guess it is happening slowly. My question is, if we don't
- de-intensify our agriculture, when do we hit the buffers? When does something really bad happen?
- So I think there is discussion about peak harvest and, the problem with statistics is that,
- you know, it's difficult to come up with these figures, but certainly we're starting to see
- that we are at the point of not increasing our harvests with the intensive agrichemical-based
- agriculture that we are running at the moment. So we're not talking about an overnight transition
- to not using agrichemicals, because we've seen in some countries, for example, like Sri Lanka,
- where they went wholeheartedly for regenerative agriculture in a one-step, bold move, that it
- doesn't work. We need to slowly move towards regenerative practises, and many farmers are doing
- that. There's exciting movements like Groundswell, where farmers are getting together and doing less
- tillage of the soil, less digging of the soil, in order to protect that microbiome and allow it to
- build up carbon, and the more carbon you have in your soil, in general, the better the soil health
- from the point of view of food productivity, etc. So, I think in terms of the soil degradation
- you're referring to, we are seeing a lot of soil being moved, but it's actually really
- difficult to measure soil erosion. There's lots of papers about the fact that it is difficult to
- quantify. What we do know is that we have, when we've studied individual soil systems which have
- been under agrichemical use for a long time, for example, at Rothamsted. and indeed talked about
- in that 2020 paper that I was excited about, is that they are critically ill, those soils,
- but the good news is that, if you do move towards more regenerative practises, by which I
- mean adding organic matter, then they recover quite quickly. So, I wouldn't be unhopeful,
- because there is a movement towards more organic farming methods in the broadest sense of the word.
- Thank you. There's one right at the back, the very back.
- Hello. I have a question. It's Fiona Harvey from The Guardian,
- and, I thank you for that brilliant lecture. That was fantastic. I'd like to ask about
- the intensification of agriculture as well. We intensified agriculture in order to feed
- more people. Is it actually possible to have a planet with 10 billion-plus people on it and
- have areas that are not under agriculture where, you know, wild creatures and so on can still live,
- and have healthy soils? Can you have all three of those things together? Thank you.
- I don't know, I'm afraid. When I've looked at the statistics and tried to understand this,
- I'm afraid I have to say that I honestly don't know. From what I read, I see that we need all
- sorts of solutions. For example, you know, George Monbiot has written a great book about the fact
- that we can have lab-based meats, we can grow our meat in a laboratory. Of course soil is not
- just for growing our crops and our livestock, it also has so many other ecosystem services
- that we need on planet earth, like controlling oxygen and carbon dioxide and all the gases,
- so we still need to look after our soils. In terms of 10 billion people on the planet,
- I think that's too many, but that's, as many people have pointed out,
- is the elephant in the room. So in answer to your question, if I'm completely honest, I don't know
- how we do it. What I do know is that we need to protect our soils and rebuild our soils,
- and look at working with communities on a local level of what ecosystem services they need,
- working with people on the contentious issue of moving towards more plant-based diets,
- eating less meat, but my feeling is, having read what I've read from a wide range of sources,
- is that we do need integrated farming. We do need our animals on the land alongside our
- arable farms, and the extremes of farming which we see, for example with the cattle ranches in the
- States, are what we shouldn't be doing. Whether we can have everybody having meat and two veg,
- doesn't seem likely with whatever sort of regenerative agriculture we're proposing,
- so I presume we're going to have some sort of lab-based meat grown, as well,
- in order to allow us to eat meat, unless we move towards insects. Sorry to give such a poor answer.
- I think it's such a difficult issue, and it's not something that I would claim to be an expert on.
- Is there an online question?
- I've got a question online from Jane. I love my allotment and
- try hard to look after my soil. Is there any way that I can add
- the iron and manganese oxides you talk about, and if so, how much and when?
- Not at the moment, because the work that we're doing is trying to
- establish the best way to do that. I don't think we're at the stage
- where we have a source where you can dig it in yourself in your garden,
- but I think it is our aim to be able to go to B&Q and buy, instead of compost, buy compost which is
- stabilised with minerals that is going to keep the carbon in the soil in a better form. So no,
- at the moment, it's adding the organic matter that you generate from your own garden,
- making sure that's returned, so you've not got a one-way take of micronutrients from the soil.
- Okay, one more. Yes, thank you?
- Just one last question here.
- Hi, I'm just curious of how do we get the conventional wisdom so set not to till the soil,
- because the one thing I picked up from your thing, I thought that was a good thing to do,
- right, because you're going to aerate it and get some - if it's getting air into it, better, no? I
- think that convention of not tilling the soil, we can see that we're not disturbing the microbiome,
- so we're allowing the carbon to build up, and if you're not compacting it, you're not standing on
- it, or you're not putting large tractors on it, then no-till is definitely a way to
- improve carbon storage. So the digging mentality that we taught everybody of double digging and
- stuff from the '70s is not good for the soil because you're breaking up that soil structure.
- The regenerative practises would tend to have a lot less tillage, and do direct seed drilling,
- so that you're disturbing the soil as little as possible, and disturbing that microbiome home, as
- it were, as little as possible, but then I, I'm, I'm also aware that in natural systems we have,
- for example - where is it that we've introduced wild boar? - that's what they do, they till the
- surface of the soil a little bit. To me, this is not my area of expertise. I'm somebody who looks
- at carbon and minerals, carbon stabilisation on minerals, but in terms of tilling in agriculture,
- it will be interesting to see what other people think about it. I think that we don't
- fully understand in natural ecosystems what the role of herbivores, etc., is in turning over the
- soil. That's just a natural part of ecosystems, but the large-scale ploughing that we have been
- doing has damaged our soil in combination with the overuse of chemical fertiliser and pesticides.
- Okay, thank you. That's all the time I'm afraid we have for questions. I'm sure you can speak to
- Karen later. It just remains for me to say what a great honour it has been to have her here, and to
- present to her on behalf of the Royal Society, the 2023 Rosalind Franklin Award for her work that has
- promoted women and women in science for STEM. I'm going to present to her a scroll. If it's here.
Professor Karen Johnson Presents the 2023 Rosalind Franklin Award Lecture titled ‘ A nation that rebuilds its soils rebuilds itself: the role of women’
Franklin D. Roosevelt said "A nation that destroys its soils destroys itself". He was referring to the American Midwest during the Dust Bowl of the 1930s, but also unknowingly foreshadowing what lay ahead.
In the EU, two-thirds of soils are now degraded, while one-third of worldwide soil experiences the issue of degradation. Soil is the biggest store of organic carbon after fossil fuels. By degrading it over the last 70 years through industrialised agriculture, we have ended up in a vicious cycle of climate change causing fire, floods and droughts. These events exacerbate soil degradation and cause more climate change.
Soils are not glamorous but they do underpin all terrestrial life. They don't just feed us, they store water and they store carbon. Soil degradation has happened because we have been treating soil as inanimate. Soil is living. Just like us, soil needs energy and materials to stay alive. But we are killing it. And unless we do things differently and start to care for soil as a living material, we will destroy nations, because we will have food shortages, we will have more floods, more droughts and fire, and we will have more inequality.
Using "waste" materials rich in the carbon and minerals (apostrophes because these materials are not waste to living soil) we can provide the soil microbiome with what it is missing so it can thrive. By working with the soil microbiome and by feeding our soils we can produce healthier plants, healthier animals and have a healthier planet. The role of caring is one that is largely assigned to women but there is a growing consensus that a caring approach can result in environmental, economic and social benefits for all. Working with the soil microbiome to rebuild our soils will help us to deliver net zero, net biodiversity gain, and to improve both human and planetary health.
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