 I would like to introduce our first speaker, Francesca Cortufo, professor and associate head in the Department of Soil and Crop Sciences and senior scientist at the Natural Resource Ecology Laboratory at the Colorado State University. The title of her talk is Carbon Sequestration in Soils. Over to you, Francesca. Thank you, Sarah, and everybody for being here today. As we heard yesterday, humanity is really facing a significant challenge with having to reduce carbon emissions from about 40 gigaton per year we are having today to zero and also have a method to drill down CO2 from the atmosphere actually to below zero in order to stabilize the climate. And we need to do that at a time when the global population is still rising and therefore their demand for energy, water, land, and food is rising as well. We will hear today a lot of different solutions. And my goal is to drive you to one of the possible player in this fight against climate change that we have, which is soil. Soils really have an important role because they lie at the nexus of these challenges because of the many ecosystem services they provide with carbon sequestration actually being one of them. And the reason why soils are so important for carbon sequestration is that they actually store an immense amount of carbon, which we used to say the standard is always the higher than the atmosphere and vegetation combined. Even in ecosystem like forests that have high vegetation, the carbon stocks are always very, very high. And so on one hand we need to remember to actually protect that carbon from accelerated decomposition due to warming and disturbances so that we don't further exacerbate climate change. As well as manage our soils to also add more carbon in them. The reason why this might be possible is that actually during the history of our use of land, we have exploited our soils in a way that actually Jonathan Sunderman recently estimated we have eroded about 120 per gram of carbon from the cropland and grazing land. And then in a way it gives us an opportunity to change the way in which we manage those land in order to accrue the carbon back. And there has been a lot of studies pointing to the ways to do this. And this from both the others is actually one of, possibly one of the most recent, that I like a variety of approaches we can use on land to either add more carbon or, and that's important to make a distinction, avoid emission from carbon. But as Chris said yesterday, this avoided emission. We need to be careful not to double counting them. This is carbon that is currently in the soil. We just have to make sure that it doesn't go into the atmosphere. Those soil carbon sequestration strategies have several pros. In particularly, most of them are relatively low cost. We know the technology that can be implemented with several common benefit to hair, biodiversity, water, food has pointed in this figure. And also, at least for what the concern of the cultural land, they don't really need more land. It's just a change of management in the land that is already under other culture. There are several limits or cons or things that we need to be careful about when we look at carbon sequestration. And those are in particularly the difficulties to quantify the amounts and the longevity. With those being the potential, there has been a lot of hype with doing it, but also a lot of criticism for whether those potential can actually be met. And what I like to do with you today is go down what I think is a road map that can help us meet those potential. And that involved, first of all, starting from the science and the biophysical soil carbon sequestration, use that understanding to have accurate maps of where carbon is in which foods are vulnerable it is so that we can target our investment. And also design specific targeted management strategies for the different contexts. But also we need to develop accurate low cost and high throughput quantification method. And in interface, our measurements with models that can use those measurements for actual verification. And then include those models in decision support tool that stakeholders and farmers and industries can use to make those decisions. And the most important point is that we need to work together. And that's why I'm very excited to be talking to these audience today because we do need to work with industry, our consultant, farmer, arrangers, policymaker, to get the infrastructure and incentive and extension that can allow to scale up those processes. And finally, I also think that we need to do research to find more innovative solutions. And so this road map is also somewhat the outline of my talk. So let's start from the biophysics. The very simple biophysics is that if you want more carbon in soil, you have to increase inputs. You have to decrease outputs. And possibly you can work with the efficiency in which carbon is converted and increase that efficiency. We have a number of approaches that we can use to both increase inputs and decrease outputs. And some of them are very well known and can be implemented immediately. Other are more in the face of research, and particularly increasing efficiencies more in the face of research. But there is some very interesting work that show that we can do that by improving the relationship between plant and microbiome, or also the nitrogen management. But what I want to do with you today is actually stress the point that this biophysics is too simple. And as a soil carbon scientist, I'm not going to tell you about the complexity and all the difficulties of studying soils, but allow me to say that we do need to make one step forward. And a knowledge that not all soil carbon is equal. And the most simplistic, the next most simple approach that we can take and can bring a way to a way better stage is to actually separate carbon at the minimum in the two most distinct fraction, which are the particulate organic matter and the mineral associated organic matter. The reason why we need to do that is because those two fractions are created by different process. And so different management respond to. They will respond differently to management. They have a different permanence with the particular being much having a much faster turnover, whether the mineral associated can actually stay in the soil for several years. And the other difference is the different in nutrition and nutrient demand. I don't have the time to go into that today. But for sure, the nitrogen demand of carbon sophistication is an important point. And mineral associated require actually more nitrogen than the particulate. The particulate is formed mostly from plant debris and structural material, where the mineral associated is formed from the soluble accident through microbial transformation. So why is it important to separate those two? First of all, palm is by far more vulnerable than man to decomposition, both to warming. And so when I was saying that we need to be to steward the existing carbon in soil, we mostly have to steward the palm carbon. But also they have a different vulnerability to management with actually the man being by far more stable and the palm being the one that we lose to the point that we have actually very little palm in agricultural soil. The other thing that is important, and we touched on it yesterday, is the concept of saturation. Since man require mineral to stabilize, its saturate and its saturation level depend on the amount and type of mineral in the soil. Whereas the palm on this other graph will not saturate. The good news here is that the majority of the soil are far below the saturation level. And these are actually grassland and forest soils in Europe. The agricultural soils are typically down here. And so we do have a high potential for sequestration. And right now, we don't have to worry about saturation that much. In particular, if we focus on carbon sequestration in the deep soil. And the best map of carbon we have for the US is this, the steel highlight areas with high potential for carbon sequestration, highlight areas where we really need to steward the land to avoid carbon emissions. But we don't have an accurate distinction between those carbon forms that can further drive management. And that's something I'm trying to do in collaboration with DNRCS and Neon. We are working on making a map of my own carbon and palm carbon. And with those understanding, we can best drive management solution. Now, the silver line here that I'm very excited about is actually we do know how to inform users about what they should do on land in order to increase carbon. And we know from a scientific perspective like this decision tree that was published a few years back. And this is actually very similar to what the practitioner like understanding of and people like Gay Brown that has learned from his experience what he needs to do on his land to sequester carbon. They are coming together. And that to me is really highly motivating and exciting. And they both come to the point that carbon sequestration is context-dependent, which means again that we need to have the background understanding. But we also need to work with farmers who educate them and give them the right decision tree. So what are those practices that we can do? There has been a lot of work, a lot of meta-analysis. Maybe what rise to the top says in this meta-analysis is the conservation pillage in agricultural land has a solid benefit for carbon sequestration, in particularly on the top soil. Pillage doesn't increase carbon at that. Same goes for cover crop. Cover crop are really great at increasing carbon and improving its quality, mostly effective in the top soil. Biochar come to a different scale because basically it's an addition of carbon-dense material in the soil that is recalcitrant and about 70% to 80% of what you put in is going to stay for centuries. But the problem with biochar is that we can't count from the moment we put it in. We need to count the life cycle of biochar from the feedstock to the moment in which we put it on land. And so depending on that, the carbon benefit can actually not be at eye. Also, grasslands can play an important role in carbon sequestration and they also receive the significant attention and the rich pond and others have done studies pointing to the potential, how different changes in management can increase carbon in grasslands. We just completed the study in grasslands in the south of the United States where we did the quantification but also the separation of mailman palm. And here I point out that by changing management to adapt to multi-pandemic, for example, we could demonstrate that not only they increased about nine tons per liter over a period of about 10 years, but also the majority of the carbon was occurred in mailman, so it was mostly. But of course, not everything is so easy and carbon sequestration might lead to end-to-war emissions. And I know that David will talk more about that later, but that's something that we need to be aware of. And this is actually a meta-analysis that hasn't come out yet in global chain biology, but it will soon. And it shows that for example, for some of the carbon sequestration for the practice that the crude carbon they might release end-to-war. And so that is something to watch out. All of these studies, or the majority of them have been done mostly as independent studies on experimental stations and some on-farm work. But what we really need to be effective is to move to a larger scale. And I am very excited about the fact that industries are actually jumping into this and helping us to move to a different scale. Indigo is playing a big role in this work and they have launched an initiative for which they are monitoring carbon sequestration in a variety of farmland all across the mid-U.S. But other similar initiatives are currently being done and supported by General Mills, McDonald's, TNC and so forth. So that's really exciting. But the moment in which we change scale, it means that we need to start analyzing thousands of soils. And so that's, I have a lab in which analyze soils and the moment in which I'm telling you that you not only have 25 carbon, but you have 25 carbon in mailman form, I also understand the importance of providing a solution for high-truth analysis. And that's something we are doing in CSU where we are working with engineers to design instrument that can automatize the, for example, the soil organic matter fractionation in mailman form and couple those analysis with the infrared spectroscopy and other methods that can analyze with a high-truth put in low-cost high number of soils. And then we need to work with the continental scale database and statistical approaches like machine learning to really get to those maps. So that's something that I'm very excited and we are working on in my lab. Finally, these kind of models that need to enter decision support tools, as for example, the already great tool like Comet Farm, Comet Planet that need to be available to the stakeholders to drive their decision. But ultimately really what we need to do and again I stress how great it is this meeting is we need to work better. A couple of weeks ago, I'm collaborating with General Mills on a project on grain farms in Kansas and we hope to expand it to Oklahoma and Nebraska. And it was great to work alongside consultants and farmers to really see and demonstrate on the land those regenerative practices and how they can again be a win-win not just for the soil health and ecosystem health but really for the economics of the farmers. Finally, we need to still move the research forward because as I stress multiple times that we do have to know how to start today, we also have to keep doing research so that we can find innovative solution that can potentially sequester even more carbon or increase the permanence of the carbon we sequester. And so for example, CSU, Matt Balliston and others are working in collaboration which is industry of all kinds to for example, study how lactobionate might have a role in carbon sequestration and you can imagine many other side product that could have similar effect. The other thing that I mentioned at the beginning that I think it can be important is improving the connection between plant and soil and microbiome to increase that efficiency and that can also be important in increasing the tightness between the nitrogen and the carbon cycle and make a carbon sequestration more effective also in terms of not using the nitrogen. And some of you might have seen a film, I don't know now that I told my lost track of time I think it was a month ago that came out in major paper from a British group that showed how we can actually sequester carbon by adding possibly silica rocks to agricultural soils. And so this is just to give an idea but for sure we still need to support research in a way that we can find a normative solution. So in conclusion, I want to stress again once more I really love the fact that we keep stressing this is that by no means what we are saying has to take away from the need to decyberize the energy sector. So that soil carbon sequestration can play an important role to help throwing CO2 down in particularly because we have that very short time scale and also because carbon sequestration has a ton of core benefits and can increase soil health and improve sustainability or resilience of agricultural soil. I think the implemented soil carbon sequestration scale is actually doable despite all the skepticism in this field and I hope I have illustrated you what we should be doing or we can do in order to meet the most of those potentials. But we do need to work together and we do need to have again, collaborative between industries, practitioners, scientists and so forth. I do like to stress and I know that I'm fight back on that because people say cost too much, the truth is low, but it is important that we move not just to consider carbon one thing and we might put dollars on carbon that stays in the soil only for a few years. It is important that we separate the carbon that might stay for longer and have a different function from the carbon that stays for a limited amount of time. I'm very excited that the Colorado State University we are actually enacting on this roadmap and creating a soil carbon solution center to exactly create those collaboratives and start working on making those solutions in reality. With that, I like to thank all my group and great collaborators and all my funders and of course all of you for your attention. Thanks. Thank you, Francesca. Great to see all that you're working on at Colorado State. I'd like to turn it over to Jenny who is running the Q&A this morning. I can see we already have a number of questions that have come in. Please use the Q&A function at the bottom of your screen and continue putting them in and Jenny will call on some folks to ask their questions now. Thanks Sarah. Thank you Francesca. It was a lovely, wonderful, informative talk. We have a couple of great questions here. Laurie Wayburn, would you like to unmute yourself when you're able to and ask a question? One of the things I would be curious about is it does sound like organic farming and holistic range management approaches are really superior methods for enhancing soil carbon. Both they have lower inputs in terms of petroleum based fertilizers, pesticides, et cetera and they have enhanced soil organism populations as contrasted with somewhat more intensive agriculture. What does your research show about this and do you have any thoughts about impediments to broader implementation of that kind of approach? Yeah, I think you're perfectly right. And actually, we have been thinking about the fact that you need to diversify the rotation and increase the nitrogen input from legumes, but when we work at grain rotation, so without all the holistic regenerative approach that you mentioned and just maintain the continuous cropping and introduce legumes in the crop rotation, we actually didn't have the same results as the holistic approach. And that's I think is because for example, the legume have low productivity has used as a grain like if you have a pea crop doesn't actually have the same amount of input and also the stage of the introducing perennial stages and diversify the root inputs. Those are all great things that only the holistic management and the introduction of animals in the rotation really move the system to a different level. So I do start to believe that to have the very announced responses and not just move the needle to a little bit, the most successful also for the economics of the farmer is to go into the holistic. How much that match the economy of agriculture today it's hard to say and maybe that's something that Dave can speak to better. But from a soil standpoint, the holistic management is the best. Thank you. We'll take another question from the audience. Jessica, would you like to unmute yourself when you're able to and ask your question? Sure, can you hear me? Yeah, thanks. Great, yeah, that was a really, really great presentation. Thank you so much. I found the map of the European palm and ma'am really fascinating and in particular, the fact that there's this abundance of palm in coniferous forests for example and in thinking about implementing nature-based solutions and considering that many of the common pathways are in the forestry space. I was wondering what your opinion is of possible amendments to forest soils to either increase the ma'am concentration or somehow increase the recalcitrance of palm in forest litter and soils? So it also depended on the soils of course and one thing I want to make sure is that we are talking about the mineral soils not the organic layer because on top of that, there is a huge amount of organic material that is even more vulnerable. The point to consider is that at least in Europe, forests, given the long history of land use, forests are on the most sandy and acidic soils of Europe and so there is this connection between the land use and the soils and how much you can do with that. And the other thing is that conifers only associate to ectomycorrhizal that also are prone to form more palm rather than ma'am. So there is an inherent limitation on how much ma'am you can sequester in forest. You can work with, again, trying to diversify the forest because for example, the deciduous forest, are actually much more similar to the grasslands than they are to the conifers and some deciduous mixed deciduous forest can also have an ectomycorrhizal that can promote ma'am formation. And so I think that for established conifers forest, there is so much you can do. If you are regenerating forests and are foresting, it's important to understand what's your soil, what's the potential and design a forest that possibly is a mixture so that you can accrue also ma'am to having more deciduous and to have more ectomycorrhizal trees. Thank you. I'm hoping we have time for one more question. We have a lot of questions that we probably won't get to, unfortunately. So Christian Davis, would you like to go ahead and ask your question once you're able to unmute yourself? Yeah. Hey, Francesca. Thank you for a really brilliant presentation. I think a lot of the work you have done and are still doing in terms of mechanistic understanding of how soil carbon accumulates is really kind of pushing the boundaries of the field. So thank you for doing that. Do you have some idea on how far away we're actually gonna be able to, how far away we are from being able to manipulate the processes to drive and increase carbon stocks? And do you think in the future we may be able to get to a point where we can just analyze a sample and kind of propose a tailored solution to farmers in the future? Yeah, so I'm actually not a strong believer of the... So I do think that my groups are the engine that really drive how much stays and how much goes and how much form is formed, how much mayhem is formed. But they respond to the management and to the plan. And so in my opinion, again, actually going back to the holistic method, I think that we are not far from creating a very integrated plant-microbe relationship. And you can get that by basically having the mutualism that we see natural system where the fungi bring, the microbes bring the nitrogen either by fixation or by scavenging to the plant and the carbon and the plant provide the carbon. So if we stop fertilizing, we start promoting that plant-microbial interactions, we are a long way there. The other thing we need to do is to have more roots and deeper roots. Plant breeding has been done so that our crops have an absurd shoot to root ratio with roots that are unexistent. And so we need to change that and we need to have crops that have bigger and deeper roots so that you can put that carbon in the soil and you can start that relationship between microbes and plants. And we know that. So I think that as long as we decide that that's what we want to address and we put the money in addressing it, it's not actually hard to do that. From the measurement standpoint, I also think we are not far out. Again, it's mostly a matter of investment. But one thing that I don't believe is that we can get accurate, we can get the type of carbon measurement that we need from throughput directly in the soil. But what we can do is to have great models that are fed by continuous water sensing data, MPP sensing data from remote sensing, temperature sensing. So once you have a good model that you can initialize with measured data and you have good sensing, continuous sensing data that's fitted, you can actually have and you can have, for example, at the tower that continuously verify the outcome. You can actually have pretty accurate carbon estimates without having to be ulting all your farms. And so we know what we need to do. If we get the investments to do it, I think we are not far out.