Kean Gao: 00:04 So currently global, total greenhouse gas emission has about 8% of it being contributed from Patriot South side and most of them is from agriculture. So conference soils within the agricultural sector, about 90% of that of the nitrous oxide emissions, et cetera, from soil. Josh Moran: 00:26 You're listening to the Wine How podcast. Produced by the Ontario Agricultural College of the University of Guelph. Where we look to answer the big questions in agriculture, food, and the environment, through casual conversation rooted in research. Josh Moran: 00:43 Hello everyone. I'm Josh Moran and today we're joined by, you guessed it, front of the show Jordan [inaudible]. Jordan Terpstra: 00:48 Hey Josh, how's it going today? Josh Moran: 00:50 Pretty good. Enjoying this chillier weather. Jordan Terpstra: 00:53 So what are we doing today? Who are we talking with? Josh Moran: 00:55 Well today I'm very excited. We're going to be talking about some soil science and we have two pretty esteemed guests in my books. We have Kean Gao and we have a Doctor Claudia Wagner-Riddle. Thank you so much for being on the show. Dr. Claudia: 01:09 Pleasure to be here. Kean Gao: 01:10 Thanks for having us. Josh Moran: 01:11 Maybe before we get going, could you maybe give us a cold notes version of maybe what your research entails and well, what's kind of going on right now? Dr. Claudia: 01:19 So in my research group we look at greenhouse gas emissions from soils, and ways that farmers can manage soil differently to reduce those emissions. So it's a pretty current topic. There's a lot of interest in that. So because of climate change, all the sectors are asking what can we do to contribute to mitigating climate change and managing soil in a proper way, is one of the ways. Josh Moran: 01:50 Your project specifically Kean, what's that look like? Kean Gao: 01:54 Yeah, I look at the nitrous oxide emission from soils. That's specifically a 16 hectare plot at Yulara research station. I'm mainly looking at how management practices such as cover crops, tillage, how they can affect nitrous oxide emissions throughout the whole year. Josh Moran: 02:15 What did you study as an undergraduate and what kind of stemmed your interest in working in this field? Kean Gao: 02:20 I started land reclamation at the University of Alberta, which involved a lot of soil science courses. And after graduation I worked in a research group for solar physics for a few years. That led me into the greenhouse gas emission research field. So by the time I wanted to pick up studying again and become a master students, I came across the research paper Claudia did 20 years ago and decided to apply here. Josh Moran: 02:54 Well I'm sure they're glad to have you come down to Guelph. That's good. And how did you sort of come to your real, Doctor? Dr. Claudia: 03:05 Well, I-, it's kind of a long story torture story, but I always liked soils, but I also like climate. So the kind of the interaction of those two things led me to where I'm today. I started back in 1994 as a professor here at the University of Guelph. And at the time, I was working with greenhouse gas emissions and I thought, "Oh, maybe I'll work on that for a while and then switch to another topic." But, it's been such a pressing issue that I basically have more work than what I have time to do, and just keep going in on this topic. Jordan Terpstra: 03:49 And so going off that, was it a popular topic of research back when you started originally? Or were you kind of one of the few people on campus doing that? Dr. Claudia: 03:59 I think it's definitely become more people working in this area. When I started it was more of kind of a niche area looking at nitrous oxide. So that's one of the greenhouse gases that Kean is studying, and now there's a lot more interest. Like what can farmers do? It kind of started, well let's look at how much is being emitted. And now it's more like we want to do something, what can we do. Josh Moran: 04:29 Now I know we use the term soil and I think everyone has a basic idea as to kind of what soil is. I mean, we all walk on ground, but could you maybe describe to me what soil is in the context of your work or maybe elaborate on what that may be? Kean Gao: 04:46 I think in general soil, it's just a mixture of everything we think that's in the soil. So, not just the mineral particles, but also foreigners or whatever, living organism is in the soil, all the air pores, all the liquids in the soil. This whole mixture is what we call soil. Dr. Claudia: 05:08 It's not dirt. Josh Moran: 05:09 Yeah. I remember a second year a Doctor John Lozan saying, "Don't call it dirt. It's soil." Dirt implies bad. Yeah. So there's lots of things too. And I remember specifically when reading the information I received from media, you focus a lot on top soil and you talked about the impacts of top soil degradation. So really what is the topsoil? What differentiates it from other types of soil? Kean Gao: 05:34 Generally topsoil is what we think it's about the top 15 to 30 centimeter of soil, or we call it normally call it a horizontal or horizon, when it's in organic soil. It's the soil horizons that's very rich in nutrients. That is crucial for plant growth, because that's mainly where the root zone is for all the plants. Degradation is very easy to happen if we don't manage our soil property. Any kind of erosion, whether it's wind or just water, they can just take out our precious topsoil. And also I like to think soil as a non renewable resource because it takes a very long time. On average, about 500 to a thousand years to form about two centimeters of top soil while that two centimeter that can be easily lost through any kind of erosion. Josh Moran: 06:36 What are some of the things that are causing this erosion of soil? What are some of the common things we see? Kean Gao: 06:42 Mainly agriculture practices. Urbanization also does that. Whenever we don't see enough vegetation on top of soil that holds the soil together, it is vulnerable to all kinds of erosions such as wind and rain. Dr. Claudia: 06:59 There have been estimates that it costs Canada and crop production about $3 billion a year, they lost or either soil loss or degradation of soil. And that doesn't include some of the other things that we derived from soil. So Kean mentioned plant production, but there's also other, what we call ecosystem services, like water filtration, carbon sequestration, that is not included in that estimate. Josh Moran: 07:29 That's interesting too, because I find that you often see soil and you just assume you know all that's where plants grow. You don't automatically associate it with those other ecosystem services as well, so it's interesting to kind of have that lens to look through as well. Jordan Terpstra: 07:45 And so when you throw out that number, you said 3 billion. Dr. Claudia: 07:48 Mm-hmm (affirmative)... Jordan Terpstra: 07:48 Does that, so does that mean that if there's some of that nutrient loss from soil, then it means that crops aren't as high quality and that's where some of that... Dr. Claudia: 07:59 Right. Jordan Terpstra: 07:59 ...money is lost? Is that what. Dr. Claudia: 08:00 Mm-hmm (affirmative)... Right. Jordan Terpstra: 08:00 That kind of... Dr. Claudia: 08:02 So the soil provides, as we know, provides the nutrients for the plants to grow. It holds the plants in place, but it does much more. So back to your point, I think that's one of the things we need to move away from is just considering the soil as providing nutrients to plants. I mean, obviously that's a really important role, but it has, it's a living organism basically that we have to care for in other ways, so it's not just the matrix where you add nutrients for the plants to take up. It's kind of, it has a life of on its own and serves to like all the water that moves into the groundwater goes through the soil. Carbon, it's a big reservoir. So it was a big reservoir of carbon, that we want to keep that way. We don't want to lose that carbon. So those are all aspects that are really important to consider. Josh Moran: 09:04 So what are the actual, I mean you talk about say carbon and soil, and things like nitrogen and soil. So what roles would these play? Why is it important to kind of maintain these higher levels of these nutrients? Dr. Claudia: 09:19 So you mean nitrogen and potassium... Josh Moran: 09:23 Yeah. And so on. Dr. Claudia: 09:23 ...and phosphorus? Well, because plants need those. But then there's also that the amount of nutrients they are removed and crop harvest. So they need to be replaced. And we've seen that fertilizers are one way. So inorganic fertilizer replaces some of the nutrients removed. But we can also add organic forms in the form of manure, or cover crops, or legumes. So I think a lot of the agriculture, the focus has been on, well let's replace those nutrients in fertilizer form, but not looking at other ways. Like how can the biology of the soil provides some of the nutrients that are needed, that you don't then have to input, so it also saves money to the farm, for the farmer. So they're all, those are all important aspects that research is looking into how to do that. Josh Moran: 10:24 And that's super important. Because I know from speaking to farmers, if you don't have to be out loading fertilizer and onto your fields, that's another expense. Right? So to be able to... Dr. Claudia: 10:33 Right. Yep. Josh Moran: 10:34 ...there's a very practical tie in. And you said specifically you're looking at a nitrous oxide emissions. Kean Gao: 10:41 Right. Josh Moran: 10:41 So is this in relation to actually the application of say these neutral, these, sorry, these nitrogen fertilizers or spreading manure on these fields. Is this one of these sources of emissions? Kean Gao: 10:53 Of course the soil has its own background emission. But in past decades when nitrogen fertilizer has been used increasingly, we do see a higher amount of nitrous oxide being emitted from soil. And because when we apply a nitrogen fertilizer, it doesn't always match the time that the plants need them. And also we have other problems with applying them in our own way, at a wrong rate at different, wrong time, or we're applying that wrong type of fertilizer. So a lot of them ended up being leached out of soil, whether it's in a casters form of nitrous oxide or alleged as a nitrate into groundwater or surface water that causes eutrophication. So yeah. Josh Moran: 11:45 You said a eutrophication, could you maybe say what's that? Kean Gao: 11:49 Basically we are supplying too much nitrogen and phosphorus into water. That causes a lot of aquatic plants to grow that blocks the sunlight and uses too much oxygen. Something like the algae bloom we see in the lakes is one of the kinds that has a great impact on aquatic lives. Josh Moran: 12:14 So over applications seems to be a source for these environmental issues associated with agricultural production, right? Dr. Claudia: 12:22 Yeah. Josh Moran: 12:23 So there's obviously a certain importance to measuring these emissions. And you said you were looking specifically at some management practices to help mitigate this. You said cover crops, so could you maybe expand on what, say what these cover crops are, or the importance of keeping vegetation on soil to produce these emissions? Kean Gao: 12:40 Sure. Kean Gao: 12:41 Normally when farmers harvest a main crop in the fall, a lot of farmers tend to leave the field just as fellow with nothing growing on it over the non-growing season. Having a cover crop during this period of time, you can reduce winter freezing, which also is a cause of spring thaw emission of nitrous oxide, and also having the cover reduces erosion. It can uptake whatever excessive nitrogen in the soil. So we can store it for a later date. And normally in the next spring farmers will terminate them, and return them back to the soil to supply the new nutrient to the new crop. So some common cover crops we use here are, they include legume specious, such as clovers, or grass zeros species, such as planting rice or any rice. Someone of us, some of our researchers also use daikon radish as a cover crop. Dr. Claudia: 13:52 Yeah. So we're working actually with some cover crop mixtures as well. So some farmers, like innovative farmers, at the kind of forefront of cover crop growth in Ontario, they're playing around with different mixtures and ideas that each plant has roots interacts slightly differently in the soil. So if you have a mixture with that diversity, you get more benefits. And so we're looking with Kean's project, we're looking at what happens with nitrous oxide. We expect it to be reduced with the use of cover crops, but there have been other studies that have shown a bit of increase. So that's why it's important to measure what is actually happening. Josh Moran: 14:42 Why would they see that increase? Do you know? Dr. Claudia: 14:46 So often the increases related to the use of legumes, because they take up nitrogen. Well they're symbiotic and the [inaudible], the carbon to nitrogen ratio of the foliage is low. So there's a lot of nitrogen supply to the soil just as if you were adding a fertilizer. Josh Moran: 15:08 And their fixers. Yep. Dr. Claudia: 15:09 Yeah. And then with that it promotes nitrous oxide emissions, but that's why in the project we're using a mixture. So we have legumes, but also the rye grass. So with that, the hypothesis of the study is that we wouldn't have an increase. Josh Moran: 15:28 And so I'm actually curious, just kind of like when I'm trying to visualize you folks conducting this research. We've had other guests on the show that will do research in our lab on plants and sometimes the turnaround time or the growth is really quick. So I would assume with your type of research you have to be very patient, because you pretty much have to wait a full growing season. Correct? For some results. Can you speak kind of more about how that, how your research might be different than a lot of other researchers, and when it comes to like timelines and things like that? Kean Gao: 15:58 For mine, a lot of the work involved in working in the field with soil. You need to collect samples regularly from soils or the gas. We also have instruments in the field that's collecting data throughout the whole year. So very intense data collection there. After we collect the samples, we do have to bring them back to the lab and analyze them. So a lot of work going on, and it takes a lot of time. Normally way longer than some other researchers, because to have some kind of result we need at least one year of data. Of course, the longer we keep them, we keep the treatments in the plots, we can see a longer effect, how they can affect the soils. That's why where we do have those longterm projects that looking at the longterm effects. Dr. Claudia: 16:54 Yeah, you're right. Look, it's 24 seven. So we have the equipment running the whole time so we don't have to be there every single hour. But as Kean was saying, we have to make sure the equipment is working. So at least twice a week, all year, somebody's going out to the field. Somebody, Kean is the somebody, and checking on the and making sure that the pumps, it's a very complex system. So the pumps are working, the filters are changed, the computer is working, the analyzer is working. So, yeah, a lot goes into a different type of research, but this is definitely a field based research Jordan Terpstra: 17:37 And to actually take these samples, I'm curious with this, so you're measuring emissions directly, right? So are you, so you're containing these soil samples and then measuring the amount that comes off? Or how does that work specifically? Kean Gao: 17:51 That is one method that I think Addison's using. For my research, I'm using the flux grading system. It essentially measures real time emissions from the field. So it's like a big tower in middle of the field that's in taking air samples every few seconds. We measure the concentration from that. Combining with other data, such as wind and temperatures, we can calculate how much nitrous oxide flux that's really happening in the field. Dr. Claudia: 18:29 Yeah. If you think of, like you have the bright idea that one easy way is, like you put a cover on the soil, a bucket and then just look at the gases that are being captured inside the bucket the method that Kean is using, if you can think of the atmosphere as a big bucket, and then we put some instruments that measure what the concentration, how much of that gas is at a certain height, and then there's a whole theory to derive, well if we have so much at this height that means there must be so much coming out of the soil. So it's relatively complex. We need to quantified the turbulence in the atmosphere, so how much the air is kind of turning around in that layer close to the ground and it's not. It's fairly unique like in Canada, for nitrous oxide, there are only two other places that use the same technique to do that. Josh Moran: 19:35 Does tillage have a big implication in terms of the actual amount of nitrous oxide admitted from soil and greenhouse gases admitted from soil? Kean Gao: 19:45 In general, yes. Every time tillage happens, you are essentially supply the micro organisms with the top soil, the organic matter on top of soil. So we do see higher emissions after tillage. And of course if the cover crop involves, includes a legume species, which is high in nitrogen, it will also simulate the nitrous oxide emission as well. Josh Moran: 20:16 And rotating crops will also have an implication as well. Right? So changing what you're actually planning on this. So how does that move up? Where does that affect it? Dr. Claudia: 20:25 Yeah, so there's a bit of an interaction between the rotation and tillage. All of those factors are important. We are, we do have another project looking at the impact of very diverse rotations compared to mono cultures and I, we don't have that, the conclusions on that project yet. But again, the idea is that if you add more diversification in terms of root growth, and the carbon and nitrogen composition of the plants that are added to the soil, you reduce greenhouse gas emissions in general. So we have so far only talked about nitrous oxide. But the other really important aspect, which other students are looking at, is the carbon storage in the soil. So a diverse suffocation of crops tends to increase carbon storage. So that is something that we're really interested in, how the carbon and nitrous oxide, how they interact as well. Josh Moran: 21:36 what sort of interactions are kind of known, you know what I mean? Or things that you can see? Dr. Claudia: 21:41 Once you add carbon, it goes back to what I was talking about the legume, if they're rich in nitrogen or not. So you may either suppress or promote nitrous oxide emissions. But then there's a whole other aspect that we haven't mentioned, which is soil health. So if we provide a lot of carbon to the soil, we're basically taking care of the soil of the microorganisms are feeding them, and that improves the structure of the soil, and aeration, and how water infiltrates, so we have less water ponding. And all of those factors impact nitrous oxide emissions. Josh Moran: 22:27 Mm-hmm (affirmative).. Dr. Claudia: 22:29 So we see that there are a lot of benefits for things like increased diversity in the crop rotation, use of cover crops. And ultimately we're not quite there yet. But you would have some kind of rating system, where you would consider all those aspects, so it's not just about nitrous oxide, it's not just about carbon. It's all these benefits, which we like to call soil ecosystem services, because there's so many of them. And that kind of captures, this term captures all those benefits. Josh Moran: 23:06 And so we've used this term microorganisms a couple of times... Dr. Claudia: 23:09 Yes. Josh Moran: 23:10 ...and I think it is common for, I think people know that there are microorganisms within soil, but what exactly are they and what is their function? Dr. Claudia: 23:18 Wow. There is a- I forgot. Now, there is a stat that in a teaspoon of soils, there's more microorganism than butter. Like it's millions and millions. So that's one of the issues. I've worked closely with Carrie Dunfield, who's a soil microbial ecologist, in her lab. They're looking at what is there, because that is a really good, we actually, we call them microorganisms because they're so many of them. Each one has kind of a different function in the soil. That's what we're referring to. The idea is that if you, or the hypothesis, again there's lots of people working on this, but is that if you provide a kind of richer diet, it's almost like people, right? There's been some analogies made with the human microbiome, the gut microbiome, that if you provide a varied diet to the microorganisms in the soil through, maybe different types of plants together, that that improves the soil health. There's lots of work going on that. That's a kind of new frontier. Josh Moran: 24:39 Would certain soil types tend to admit more, say a clay versus a sandy soil versus a, like a more loamy or silty soil? Kean Gao: 24:49 I would say it's more linked to soil organic- Josh Moran: 24:51 Okay.Yeah. Kean Gao: 24:51 matter content. Dr. Claudia: 24:53 Yeah. But also like the texture Kean Gao: 24:57 texted, it does have an effect. Dr. Claudia: 24:57 Yeah. So what you were saying clay, it all then relates back to the airration. How well airrated the soil is, because we tend to have a lot of nitrous oxide when the soil is very wet. So that's what, why a thaw, we get a big flush. When there's a big rain in the spring, we get big emissions. And so if the soil drains better or, yeah, if it drains better than you tend to have less nitrous oxide emissions. Josh Moran: 25:29 And even say like the management practices associated with the different soil type, would that be another common thing? Say a having to till clay more often than you would with sand, or whatever, you're able to actually do a no till on as well with that kind of play a roll? Dr. Claudia: 25:44 Yeah. Yeah, definitely. Jordan Terpstra: 25:46 And then so, as we're talking about different soil types, we've already kind of talked about how your research is very applicable to producers. Obviously in Ontario, is your research, because I'm assuming soil and different parts of the world is going to be very different, so is the research that's conducted in Ontario, is it still applicable the findings in other parts of the world? Or is it kind of have to be like it's used within the area it's conducted? Dr. Claudia: 26:14 So it definitely, there's one aspect that is the applied like to test it locally to know what the effects are, but then there's also an aspect that is more about the understanding. So if I do, or we do, a study in like a loam soil, and we related to some fundamental principles, "what is the oxygen content, the water content, or the microbes", then we can potentially translate that. It's not that to other locations. Yeah, definitely. Josh Moran: 26:55 And we talked specifically about nitrous oxide, and I know we all talk about like take carbon being released into the atmosphere. I'm just curious about the actual potency of this type of greenhouse gas versus other greenhouse gases since we're the topic. Kean Gao: 27:09 Sure. Nitrous oxide, it has, there's a term called global warming potential that basically measures how effective this type of gas is for a global warming. If we can't carbon dioxide as one. Then on the unit base, unit weight or unit mass per unit mass spaces, a nitrous oxide is about 300 times of that of CO2. So it is actually a very potent greenhouse gas. And it also depletes ozone layer, and it tends to stay in the atmosphere longer. And it's definitely harder to capture then, the carbon dioxide. So currently global, total greenhouse gas emission has about 8% of it being contributed from nitrous oxide and most of them is from agriculture. So cropland, soils. Within the agricultural sector, about 90% of that of the nitrous oxide emission is actually from soil. Josh Moran: 28:25 That's wild. So when you talk about the timing of application for, say nitrogen fertilizers, as being something that's very important...So how can a farmer, how would a farmer know when is the appropriate time to apply so you are best able to reduce these emissions. Kean Gao: 28:44 So Canada actually has this program called the four R's, that promotes the right application rate of fertilizer, right type of fertilizer, and right timing of fertilizer. What was the other one? Dr. Claudia: 29:03 Right placement. Kean Gao: 29:04 Right placement. Yeah. So all of them contributes to how this nutrient supply can match the demand of the plants. That increases the efficiency of using the fertilizer and reduce leaching. Dr. Claudia: 29:20 Yeah. So ideally it would, back to your question of how a farmer would deal with this would be, if instead of applying all the nitrogen needed by the crop upfront, it would be applying just the bit like a starter fertilizer and then testing the soil. Or how the plant is growing, and depending on weather conditions, then you applied just with is needed, right? Josh Moran: 29:46 Mm-hmm (affirmative).. Dr. Claudia: 29:47 Because if the yield predictions are less, then you can adjust later on. So that is the timing that we talk about. So that can potentially can reduce emissions quite a bit. Josh Moran: 30:02 Would there be value in kind of understanding the nutrient value in your soil before and as well? So say you wouldn't put a soybean or a legumes on an extremely nitrogen rich field to- Dr. Claudia: 30:12 Right, Josh Moran: 30:12 -begin with. Dr. Claudia: 30:13 Yeah. So there's also the spacial management, as well as what you're just talking about using the nitrogen credit, right? Josh Moran: 30:21 Mm-hmm (affirmative)... Dr. Claudia: 30:21 So if you had a cover crop before, or if you applied manure, then you know how much, and so adjusting your application to account for these other sources is important. Josh Moran: 30:35 Is it these... is it like manure or is it these synthetic fertilizers that are typically associated with higher emissions when it comes to? Or does it not really matter? Dr. Claudia: 30:45 Yeah, all of them. Kean Gao: 30:46 Yeah, all of them. Josh Moran: 30:47 All of them pretty much, yeah? Kean Gao: 30:48 Whatever that contains enough nitrogen. Josh Moran: 30:50 Mm-hmm (affirmative)... So are there currently any initiatives going on here at the university or around that helps support a more sustainable soil usage? Dr. Claudia: 31:01 Yeah, so we have a couple of things going on. The first one is we've launched a, it started in April, but it is a a six year training program, called An Answer Create. That's a collaborative research and training program that is specific to graduate students, but also some undergraduate students. In the training is in climate smart soils. So the idea is that these students will do their thesis research in an area related to climate smart soils, but also they will get training in professional skills in, they will have internships with industry related to creating what we're calling these natural solutions to the climate change. So that, keep an eye out for that. We will have recruitment opportunities for students to join one of our profs working in this area. Dr. Claudia: 32:08 And the second initiative is the Soils at Guelph. That's a communication and outreach program or initiative that was made possible by funding from some donors. And the idea there is that we are serving sort of as a hub of information about soils, in terms of opportunities for people. Keep an eye out again for events that Soils at Guelph is organizing as well as opportunities for volunteering. In terms of some of these outreach events. Jordan Terpstra: 32:48 So we've been talking about soil obviously and about some misconceptions, but can either of you to pinpoint like one certain misconception that you find you get when it comes to soil, and soil health, and kind of how you try to combat that with the general public? Kean Gao: 33:06 Not necessarily in Canada, but in a lot of the developing world. Where I'm from China, that a lot of farmers who are not informed well, they tend to think the more you apply for fertilizer the higher yield you will get, which lead to a lot of problems with the soils. So it's not that. It's just the amount of the plants need. That's all you would need to apply. Dr. Claudia: 33:36 Yeah. I think from my point of view, a misconception is that soil is not interesting. I think people just look at it and we talked earlier, but it's not dirt. But I think people just look at it and say, well soils, there's so much. We have a soil physics, soil biology, soil chemistry, so you can apply some really very fundamental and sort of high tech science to soils, which people really have no idea that that exists. I think the misconception is that, "well it's just something that's there and that what is there to study about it?" And this so much we don't know about soils. Josh Moran: 34:19 It's the key factor for all life. Dr. Claudia: 34:21 Yes. Josh Moran: 34:22 Reality is. Dr. Claudia: 34:22 Exactly. Josh Moran: 34:24 So we are running a little bit low on time. If you guys are interested, I'll ask you maybe, say, three more questions. So is there anything going on that's exciting that you'd like to share with our audience? Is there any new, anything new going on in either of your lives or with your research? Kean Gao: 34:44 I'm just starting to get into last year's data. So hopefully something exciting will be there. That matches my hypothesis. Dr. Claudia: 34:56 I think... So exciting stuff. I talked about the two initiatives.... Josh Moran: 35:01 Mm-hmm (affirmative).. Dr. Claudia: 35:02 ...we have. We had some new people joining our group this fall and looking forward to more students next year. I also didn't talk about the soil lysimeter facility, so... Josh Moran: 35:17 Which is amazing by the way. Dr. Claudia: 35:20 Which is still, it's not new anymore, because it started in 2016, but we're actually just getting data out of, well we've been getting data from the start, but just kind of getting some concrete results. For example, one is that the use of cover crops over one of the winters reduced nitrate leaching, so in nitrogen loss through the bottom of the soil by 70%, so... Josh Moran: 35:50 Wow! Dr. Claudia: 35:50 ...that is a really kind of important number. I was, we kind of went into this knowing, well it has some benefits, but I wasn't prepared for how large the benefit was, so that is really exciting. Josh Moran: 36:08 That's really, really incredible at 70%. That's insane. Jordan Terpstra: 36:11 And could you actually just quickly describe what the soil lysimeter is? Dr. Claudia: 36:14 Oh yeah, so those are large cylinders filled with soil. Actually, I shouldn't say filled with soil because they were extracted in a way that kept the way the soil is so it's not putting soil in but actually basically pushing the cylinder into the soil. And then lifted out of the ground and put into a facility that has a concrete well, and it has instruments at different depths. It's a high tech facility that allows us to monitor in very much detail everything that's going on underground, and that is installed that the Yulara Research Station. It was a funding of 2 million that we obtained a few years ago, and it's going in full force and collecting lots of data. Josh Moran: 37:08 And I'd ask you guys if you'd have any shout outs you'd like to give. Kean Gao: 37:12 Yeah, of course. To Cameron, our communication coordinator, who linked us and made this happen. Dr. Claudia: 37:22 Yeah, our whole... Kean Gao: 37:22 Yeah. Our whole lab essentially. Dr. Claudia: 37:24 Yeah, we have Sean Jordan, who keeps us all in line, very dedicated technician, and a whole bunch of other people that are too many to name. But yeah, thanks for, without their hard work, we wouldn't be here talking about all this stuff. Josh Moran: 37:43 Thanks. Thanks again for being on today. This was an excellent talk and it was interesting and I think it does soil some justice, and it's good to share and say that it's more than just quote unquote dirt. And so thanks again for being on, and thanks again for being on here with me again here, Jordan. Jordan Terpstra: 38:02 Yeah, of course. Josh Moran: 38:03 That all being said, take care. And until next time. Josh Moran: 38:09 The Why and How podcast is published by the Ontario Agricultural College of the University of Guelph, and produced by Stephanie Craig and Jordan Terpstra. Recording and editing done by Jacob HighSeq and Kyle Richie. The host is me, Josh Moran. Funding for this episode was provided by the W. S. Young Memorial Communications Grant through the OAC Alumni Foundation.