Dr. Dedrick Davis is an Assistant Professor in Soil Physics at Alabama A&M University. He obtained his PhD in Soil Science and Environmental Science from Iowa State University,and his teaching expertise is in soil physics and soil hydrology. He has published research papers in national and international scientific journals, as well as several book chapters, and he has taken part in national and international congresses, including recently, when he was invited to join a national panel discussing Climate-Smart Cotton.
Our scientists have decades of experience helping researchers and growers measure the soil-plant-atmosphere continuum.
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The views and opinions expressed in the podcast and on this posting are those of the individual speakers or authors and do not necessarily reflect or represent the views and opinions held by METER.
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BRAD NEWBOLD 0:00
Hello everybody and welcome to We Measure the World, a podcast produced by scientists, for scientists.
DEDRICK DAVIS 0:08
So with biochar, I think the original interest in it came from the terra preta soils that are out in America inches there. But here in the United States, I think when there was interested in biofuels and the pyrolysis process, and it’s used to produce those biofuels, when this process is used, you get three products, which is the fuel, the oil, and then also the ash from the biomass that has been burned. And with biofuels, the thought was if you’re going to be taken off this vegetation for the production of biofuels, what can we do to make sure that it’s a sustainable process, and the thought was that we have this ash it is a stable form of carbon that can be returned back to the soil. And there therefore we can potentially increase the carbon in the soil sequester carbon.
BRAD NEWBOLD 1:00
That’s a small taste of what we have in store for you today. We Measure the World explores interesting environmental research trends, how scientists are solving research issues, and what tools are helping them better understand measurements across the entire soil plant atmosphere continuum. Today’s guest is Dr. Dedrick Davis, associate professor in soil physics at Alabama A&M University. He obtained his PhD in soil science and environmental science from Iowa State University, and his teaching experiences in soil physics and soil hydrology. He’s published research papers in national and international scientific journals. And he’s taken part in the national and international congresses, including just recently when he was invited to join a national panel discussing climate smart cotton. And today, he’s here to talk about his many research projects at Alabama A&M. So Dedrick thanks so much for being here.
DEDRICK DAVIS 1:50
Thank you for having me. I appreciate the invitation to share with you what we have going on here at Alabama A&M University.
BRAD NEWBOLD 1:57
Great. So we do want to start off definitely we want to get into all of your projects and research interests. But first, can you tell us a little bit about your your background, and how you became involved in soil science and in the the field that you find yourself now?
DEDRICK DAVIS 2:15
Um, so my background, I’m from Alabama, native of Alabama, and actually, I grew up probably about 30 miles away from here away from Alabama A&M University in a small rural community. And my family I come from a farming family. But probably about the time that I was starting to get into being an active or play and active role on the farm. My grandfather decided to retire from farming. So I stayed active through crop scouting with my uncle. So I’ve always had a heart for agriculture and was always curious about some of the things that my grandfather did. When it came to farming. One of the things I noticed that he always did. He did cotton. There were never any rotations. No, no, there was no tail was not used. So you can really tell it is by its impact on the cotton that was grown, I got to see when he took that same land out of production and put it in pasture for a number of years, and then returned it to cotton production, I got to see the increase talking yield, you could just tell the physical difference in the growth by the growth of the plant. So that got my curiosity to go on about agriculture even more. And when it came time to pursue or go to college, I had to choose a major. And the major that I chose was forestry here at Alabama A&M University. This is where I did my undergrad. But as part of the forestry program, one of the classes we had to take was intro to soil science. And in the intro to soil science class, I had an instructor that made soils seemed like they were the coolest thing ever. So once I took that intro to soil science class, I ended up switching my major to environmental science with a soil science concentration, ever since then I’ve been in soil science. And from Alabama A&M University I went to Iowa State for my masters did that under Dr. Sally Lawson, in soil physics and then PhD in soil physics with Dr. Robert Boyd. I think the cool thing about soil physics was there were things that were moving things at play just really seem interesting to me. And that is the route that I’ve taken so far.
BRAD NEWBOLD 4:37
That’s interesting. There’s a lot of similarities. We’ve had other guests on who are current experts in soil science. A lot of them have taken a similar route where they’ve started out somewhere else took a class, whether in college or whatever. I like oh man, so super exciting. Who knew that soil could be so exciting, right?
DEDRICK DAVIS 4:54
Yes, I totally agree. Like I said, I came into the forestry program for one; there was a promise of paying for your college education, but also to you have a job. And I realized, forests, they need soil scientists also. Yeah, I was like, Alright, there’s a route. So again, switching to that soil science major was very important for me.
BRAD NEWBOLD 5:16
It always seems, especially for those not in the soil science field, that the vast majority of the human population takes soils for granted. We walk past it, we walk over it, you know, we get our food from the store or whatever, and the whole world of soil sciences, we’re oblivious to it.
DEDRICK DAVIS 5:35
Yes, we are. We’re totally oblivious to it. But I think once you’re made known aware of what soil does what it provides, it’s hard to not acknowledge that, and then not even to become interested in it, just talking to people when I tell them what I do. And then I might go into what soil provides or how affects our everyday lives. There’s an interest there even from like as a just talking to the public.
BRAD NEWBOLD 6:02
So you talked about crop scouting with your uncle, can you go in a little bit detail about what crop scouting is?
DEDRICK DAVIS 6:09
So the crop scouting idea was for cotton here in Alabama, in the north Alabama area, and he usually contracted with farmers. And basically what we did with cotton scouting is we would go to certain fields that the farmers contracted with my uncle, and we would scout that cotton field for pest get an idea of what pests are there. And then, depending on what pests are there what we noted, the most, I guess, numerous type of pests, we would then go and we would recommend pesticide applications for that specific cotton field. And this is done to help reduce the impact of those past on that yield for cotton that that farmer hope to get from that field. I think it was something that was very important and a service that they need.
BRAD NEWBOLD 6:59
What are some of those primary pests that cotton farmers are dealing with nowadays?
DEDRICK DAVIS 7:02
Probably the biggest one being that we have to keep a lookout for it was boll weevil. And there was some other pests that were I can’t even recall right now because it’s been so long, but some other ones that we were concerned about, but that were pretty prevalent back then.
BRAD NEWBOLD 7:19
Interesting. All right. So you are now a professor of soil physics, can you go into a little bit more detail as to what exactly is encapsulated within soil physics within soil science?
DEDRICK DAVIS 7:34
I think when it comes to soil physics, at least the way I explained it to my students, soil physics is the study of the physical properties of soil, but also the physical processes that are occurring in soil. And those physical processes being the transfer of water or the movement of water, or liquids, fluids, movement of gases, and then also the movement of energy throughout the soil and those processes that are at play there. And a lot of the physical properties that are involved impacts these physical processes that occur in the soil.
BRAD NEWBOLD 8:14
All right, so you were recently a panelist at the cotton sustainability conference. And the panel was entitled us climate smart cotton goals projects process. Can you tell us a little bit about what was going on with that initiative there?
DEDRICK DAVIS 8:29
That initiative is to increase the adoption of what we would call climate smart agricultural practices for cotton production. And a lot of those climate smart practices being mostly soil based. When we think of these climate smart ag practices, they can have reduced tillage or no till the use of cover crops, specifically for cotton production. Even though we’ve heard about reduced tillage, and no till and the adoption of cover crops. If I go out right now outside of my office, and I take a ride around here in North Alabama, I can see that there’s quite a few acres that were under cotton production, that don’t have a cover crop that possibly where no till is not implement. So I think we still have a long way to go when it comes to the adoption of these climate smart ag practices for cotton production, especially here in Alabama. So this project is here to help encourage the adoption of these practices. But one of the things that I think is missing in us also being noted is, a lot of times farmers are hesitant to adopt these practices because there’s no proof of if they adopt this practice, how it might improve the health of their soils. So this project will go into gathering information regarding soil health, how these practices increase the health of the soil, but also to possibly help To establish a target for soil health as it relates to cotton production here for soils in Alabama.
BRAD NEWBOLD 10:08
I’ve heard the same thing from other guests about the farmers and growers are very conservative in their practices, it is definitely a risky proposition for them to change the way that they grow their crop. If there’s no direct proof, they need to see that these practices will then improve their yield further on, do you have any tips on how you’ve been able to try to communicate those best practices?
DEDRICK DAVIS 10:33
I think probably the best tips are just staying in communication with farmers but also to I think the other thing that is probably a big help is that farmer that is probably hesitant actually seeing it implemented, and being beneficial on another farm. So I think that Farmer to Farmer interaction networking, in regards to the adoption of these practices is very important. Because I can say, I’m on the academic side, and I can advocate for these practices all at once. But until they’re able to actually see them in place, and the actual improvements from those practices, I think, just blowing hot air. So I think that is probably the biggest thing. To give you an example, I still have to talk to my uncle about even adopting some of these practices. So I think just staying in constant communication with farmers, but also having having an example for them to see the benefit of these practices is very important.
BRAD NEWBOLD 11:39
What is it about no till or cover crops that then have become best practices when it comes to sustainability or climate smart crops?
DEDRICK DAVIS 11:49
I think when it comes to no till it’s less tillage, of course. So we’re hopefully enhancing carbon sequestration within that soil, but also to if we’re enhancing the carbon, maybe we have also these other benefits that are associated with this, such as increased water storage within that soil, or water availability within that soil. And that’s important, especially for areas like here in the southeast, where during the summer, we can experience times of drought during the growing season. But also to with the implementation of notes yield and also cover crops, hopefully we’re seeing a reduction in carbon dioxide fluxes from that soil also. And I think probably the biggest thing that I see with the use of cover crops, and I’ll speak here for Alabama, we receive a lot of our rainfall from the time period of November, so possibly, probably around April and May. And we get a lot of heavy rainfall. And for those soils that have no cover on them, protecting them, no cover crops, the amount of erosion, the amount of spilling, taking place is unbelievable. So just from that point of view, I think Cover crops are beneficial, especially here where I’m at in North Alabama.
BRAD NEWBOLD 13:07
So does soil health in Northern Alabama in that region, is that going to look different than elsewhere?
DEDRICK DAVIS 13:14
I think it will be different, I think it will be we can say reduced tillage and cover crops and things like that. But I think if we get very specific about it is going to be very different than say some other part of the country, I would hate to do a one size fits all approach for soil health, where you might have one thing for soil health in Iowa and you try to apply that same thing here in Alabama, it’s not going to work. Because our soils are very different. Our soils here in Alabama are highly weathered, I think inherently lower quality soils because of where we’re at because of the weathering that has taken place over time. So the needs for our soil is going to be different than say somewhere else. And I think you have to really consider that when it comes to soil health here in Alabama, and then also to considering cropping systems that are in place, what are we growing? And things like that? I know for instance, I say no till, but also to I know I’m not on the farm, but I know farmers have experienced times where if they implement no till sometimes they complain of compaction with long term no till. And that affects plant growth also. So what we do here is probably going to be different than somewhere.
BRAD NEWBOLD 14:32
Now a lot of or so many research projects are also delve into this when it comes to land use practices. And can you talk to us a little bit about the importance of the variability that can occur when it comes to different land uses and the properties of the soil whether it’s hydraulic conductivity or water retention or other things like that?
DEDRICK DAVIS 14:52
I think when it comes to land uses, you’re going to see big differences as far as some of these soil hydraulic properties or processes that we’re usually concerned about. For instance, the one of the things that I’m studying here at Alabama A&M is looking at the impact the land uses on soil hydrology. Specifically, some of those land uses that we’re looking at include like, for instance, a loblolly pine plantation, also row crop agriculture, so soybean, and then also corn, a pasture is also included in that. And then if I can get my way, I would like to, hopefully within the next year or so six months to a year and set up a residential lawn site, because all of these land uses, they’re going to affect soil hydrology in different ways. For instance, a loblolly pine plantation is not going to be highly disturbed. And you’re probably going to have more macropores there that can facilitate water flow, high rates of water flow through that soil, say compared to highly managed row crop areas such as corn and soybeans, where you can have significant amounts of compaction that can occur that can reduce the flow of water through that soil. And then you have pasture, which again, it’s not as disturbed as the row crop area, but it’s going to affect hydrology in the soil differently than the row crops, then the loblolly pine. And then here, I mentioned in residential launch site that I would like to set up. And that is important because here in North Alabama, in Huntsville, we’re experiencing rapid growth. So a lot of the farmland that I see they’re growing houses now. They are turning into subdivisions, right. So that hydrology that we’ve seen those runoff, things like that infiltration that we’ve seen under these previous land use is obviously going to change with the conversion of this land from say, row crop agriculture to now housing subdivision. Right. So I believe, in order to be able to effectively manage water, we have to have an understanding of how these different land use influence to hydrology.
BRAD NEWBOLD 17:08
Along with that, we’ve seen a lot of folks, a lot of our customers and other people that we interact with, there’s a lot of new research projects pointing towards agroforestry. And I was wondering if I could get your take on pros and cons of agroforestry? And the implications for it going forward?
DEDRICK DAVIS 17:24
I will be honest with you, I don’t think I have too many cons associated with it. I did my master’s research in riparian buffer. So a little bit of agroforestry there but also to one of the projects that I have here at Alabama A&M University is an agroforestry project in I think agroforestry, depending on what is being used for and I will our target here is for increasing the income potential for small size farms and minority landowners here in Alabama. agroforestry has looked as a way to do that, when we think of agroforestry from that perspective is something that can give farmers income in the long term with the growth of trees. But in this specific project, which is an alley cropping project in the area between the trees, the growth of specially vegetable crops can give farmers income in the short term. So you look at it, the income benefit is there. But also to I think the benefit is there from an environmental and sustainability point of view. Because the trees are going to be there for a long time. Our hope is is that the trees are contributing to mastering carbon, building up the amount of carbon in soil, but also to, that growth of the vegetables can help to produce food, I guess, for different populations that like those specialty vegetable crops, especially with the cost of produce and food these days and inflation. I think can be something that’s beneficial.
BRAD NEWBOLD 19:06
So do you see that then as as more so more sustainable, but also more resilient. Practice when it comes to to growing, especially within the face of like you mentioned, you talked about you know in inflation and other global issues right now, but especially within, you know, in the face of climate change and, and how the climate is, you know, becoming much less predictable or stable year to year.
DEDRICK DAVIS 19:32
I do think it can be viewed as resilient. And I think it can help reduce the impact of climate change, if you can help to reduce the impact of climate change with agroforestry. But also to I think the important thing is people these days, I think, want they’re food more localized. So there’s another route for you to get food that is grown within your local area if that farm is successful utilizing agroforestry for the growth of vegetables like we’re doing in this project that we have going on here. So I think it’s benefits from both of those perspective.
BRAD NEWBOLD 20:07
Are you seeing much luck with adoption?
DEDRICK DAVIS 20:09
I think that adoption, people are open to it. Our specific project is geared towards the minority farmer.
BRAD NEWBOLD 20:15
Okay.
DEDRICK DAVIS 20:16
So they’re pretty open to adoption of it. And again, loblolly pine, those are the trees that were using also, pecan trees. Were using that in our study here. So they’re very open to it. But also to, I think they’re open to it because it gives them multiple income streams. So they can grow the crops, they have the trees, and in some instances with others that are doing research here in Alabama, they also look at grazing goats, okay, within an agroforestry or civil pastoral system, right. So there’s a lot of different routes and a lot of interest here for people to go and the interest is there.
BRAD NEWBOLD 20:54
Can you give us a brief introduction into into biochar, what it is how it’s used, and its importance and future uses?
DEDRICK DAVIS 21:00
So with biochar I think the original interest in it came from the terra preta soils that are in South America and the interest there. But here in the United States, I think when there was interested in biofuels and the pyrolysis process, and it’s used to produce those biofuels, when this process is used, you get three products, which is the fuel the oil, and then also the ash from the biomass that has been burned. And with biofuels, the thought was if you’re going to be taken off this vegetation for the production of biofuels, what can we do to make sure that it’s a sustainable process, and the thought was that we have this asset is a stable form of carbon that can be returned back to the soil, and therefore we could potentially increase the carbon in the soil sequester carbon. So that is where the interest in biochar originated from, or at least this is what I’m familiar with. I’m doing my time and my work with biochar was that you can return it as a soil amendment that can be used to enhance the physical, chemical and biological properties of soil, for the production of biofuels.
BRAD NEWBOLD 22:13
How is biochar applied to the soil? And what are some of those specific characteristics that it can help improve?
DEDRICK DAVIS 22:20
The biochar has been applied, like I said, as a solvent with the hopes that it can enhance soil fertility, but also to enhance the physical properties of that soil, and then also affect the biological properties of the soil. All with the thought of enhancing all three of those some of the ways in which it has been applied and some of the things that we see that have taken place from studies that have been conducted is, for instance, if you apply the biochar to the soil is it looks way different than the soil itself. For instance, the biochar will reduce bulk density or soil compaction, but also potentially increase the water holding capacity of the soil due to its characteristics, but also to how it enhances the porosity of the soil through the reduction of bone density. So things like that is the ways that people looked at it as a soil.
BRAD NEWBOLD 23:15
In your mind, were some of the next steps. What are some things that we can do to improve that use of biochar?
DEDRICK DAVIS 23:21
I think next steps and I’m speaking strictly from a research purposes, understand how it performs long term. A lot of the early studies with biochar have been in a lab, or as there have been field studies, those field studies have been very short term field studies. So collecting the long term data to see how it impacts the physical, biological, and chemical properties of soils is going to be very important, but also to I think, in understanding how it’s going to impact crop yield and things of that nature is going to be important. And the more data that we get better of an idea we’ll have other use of biochar as a soil amendment. So I think those are probably going to be the next important steps for biochar usage. But then too, I know there’s also people who are looking at it from an environmental perspective and looking at it’s impacts on processes such as reducing the flow of chemicals or things like that in soil. So I think it’s very important that we continue to evaluate biochar and its potential impact
BRAD NEWBOLD 24:26
for the other soil scientists and so physicists in our audience, what are some of the more specific measurements you’re taking or how is your lab and your field research set up?
DEDRICK DAVIS 24:36
Well a lot of our work has been with evaluating the impact of biochar physical properties of soil specifically soil water retention, and thermal property. Because my thought has always been if you have biochar, you’re going to apply it to the soil and then you’re probably going to mix it in or incorporate it into the soil the upper part of the soil or near soil surface environment. And when I say near surface soil and soil surface environment I’m talking about from the soil surface down to maybe 15 centimeters in depth. So when you add this biochar there, to me that influences a lot of these physical processes and properties that we see that occur in soil. To me, the ones that are the most important are going to be soil water retention, because that biochar could potentially enhance the amount of water that is retained in soil. So one of the things that we’ve tried to do is we tried to measure the impacts those biochar on slow water retention from saturation to oven dry condition, near the soil surface, near the soil surface, you have a lot of processes that are occurring, specifically heat and water movement that play a role in these processes such as the evaporation of water from soil, and we know that near the soil surface, our soil water contents can vary from near saturation to extremely dry. So having an understanding of the soil water retention curve from saturation to oven dry conditions are very dry conditions can be, in my opinion very important to when it comes to modeling, or having an idea of how biochar impacts these other hydrologic processes such as the evaporation that occurs in soil. The other aspect that we’re looking at is looking at the impact of biochar on soil thermal properties. There’s been a lot of work looking at the impact of biochar on soil fertility, soil biological properties and processes. Also physical properties. There’s been quite a bit of work done there. But when we look at his impact on soil thermal properties, there’s not a lot of work that has been done there. I think the last time I looked at the number of articles that have been published where people have evaluated the impact of biochar on soil thermal properties, I think it was probably around 40 articles that have been published. This is a low amount of research when you consider biochar research has really been going on heavily for probably like the last 15 years. Those are what our studies are concerned with.
BRAD NEWBOLD 27:18
So can you talk about poultry litter, what it is how it is used as a soil amendment as well.
DEDRICK DAVIS 27:24
In short, poultry litter is the bedding that is usually taken up from poultry production houses, and it’s looked at as a deep fertilizer source for crops because it’s high in nitrogen. Alabama is a one of the leading states in broiler chicken production. In the United States, I think we’re like, maybe number three, four, maybe five, somewhere in there, but we’re near the top. And so we have a lot of poultry litter here in Alabama that poultry litter is usually applied to pastures as a way to dispose of that poultry litter here within the last year it’s been beat, it’s been applied to row crops, because of the increase in fertilizer prices. So application of this poultry litter is occurring every year here in Alabama. The other thing with poultry litter is when you apply this filter later, a lot of times it can be broadcast. So surface apply, can then potentially incorporated mixed in with the soil. So there are some environmental concerns that arise from that one being runoff, but also see you have ammonia that is volatilization that is occurring, but also to the odor that occurs with it. So it’s not a very pleasant odor. So you have all these environmental concerns that occur. And one of the things that has that researchers have developed is a way to place this poultry litter below the soil surface with the implement that can basically open up a trench in the soil, place the poultry litter probably about three centimeters below the soil surface, and then put another layer on top of it being a soil physicists and one of the things that I’m interested about is water and heat movement near the soil surface. It became an interesting setup for me because you have sort of this non homogeneous system where you have soil poultry litter and soil underneath. Yeah, and this like I said, is very close to the soil surface. And some of those processes that are occurring that I mentioned with biochar heat and water movement, they can be impacted in my opinion through the placement of that poultry litter that is there because you have this non homogeneous system or heterogeneous system where you have soil poultry litter, soil, poultry litter is going to retain water way differently than the soil, but also to is going to affect the water flow differently compared to the soil. So that is where my interest in poultry litter stems from.
BRAD NEWBOLD 29:51
Alright. Do you have any preliminary results from from any of your studies yet?
DEDRICK DAVIS 29:56
Yes, we do. One of the things that we’ve been looking at is we’ve been like In that the effects of poultry litter or comparing water vapor absorption with in poultry litter to that of soil using a water vapor absorption analyzer from METER, we looked at water vapor absorption isotherms for poultry litter and we looked at the drying and also the wetting and what we saw was was that there’s a considerable amount of hysteresis that occurs with the poultry litter compared to the hysteresis from the two soils that we evaluated one being a sandy soil and the other one being a silty clay loam soil these different degrees of hysteresis leads me to think that the poultry litter impacts water movement differently than the say the to soil if we only had soil there. So to me that sort of gives me the opinion that hey, we have to consider the effects of this poultry litter and the impact it might have on water movement in the soil, especially under dry conditions when compared to the soil itself especially if we have a system where we have soil poultry litter and soil.
BRAD NEWBOLD 31:07
So, really quickly for the non soil scientists can you describe hysteresis and what that entails.
DEDRICK DAVIS 31:14
So, soil undergoes wetting and drying daily, we can have drying that occurs, but then also too we can have wetting that occurs. In soils, we measure what is called the soil water retention curve and we look at the relationship between what we call matric potential, and water content. That matric potentials tells us how tightly that water is held in soil and usually the matric potential gets more negative. So as held with greater energy, as the soil gets drier, it would take more energy for us to extract that water from soil. As it gets dry, we can have a drying curve, but we can also have a wetting curve. Even though we might be at the same water content, our matric potential is not going to be the same depending on whether we’re wedding or drying because of properties of that soil, whether it’s the porosity or whether it’s the surface effects. So when I say surface effects, these will be related more so to the texture and things of that nature is going to determine what we see as far as that hysteresis that is that occurs. And that hysteresis which can be viewed as the difference in water content at the same matric when we’re have a wetting and a drying
BRAD NEWBOLD 32:35
With a poultry litter then just based off the characteristics how much needs to be applied for it to really make an effect on improving the soil you know, soil health or the various soil characteristics that you’re looking at.
DEDRICK DAVIS 32:47
Usually, within that culture litter is applied, it’s applied based on nitrogen content what studies have shown because Alabamian and previous to my arrival here, um, there were some researchers who actually did long term studies looking at poultry litter application along with cover cropping and reduced tillage that poultry litter when it’s applied, it can be very beneficial to the properties of the soil from like chemical and biological perspective, but also to a physical perspective. I know one specific study that was conducted by a former grad student here, they actually saw enhancement of soil hydraulic conductivity and some of the physical properties such as a reduction in compaction or bone density with the use of poultry litter for a long, long time. So that poultry litter has a big effect as far as what we see as far as soil health, because you’re basically adding them on a grant an organic material to the soil, that provides nutrients, but also to it does a very good job of improving the physical properties of that.
BRAD NEWBOLD 33:56
one of your other research topics is looking into the application of biopolymers within soil for soil stabilization and other applications kind of more on the geotechnical side of things. Can you give us a little introduction to bio polymers and how they’re used in in soil stabilization.
DEDRICK DAVIS 34:15
So on the geotechnical side, there’s been interest in the use of bio polymers and biopolymers being things such as that can gum things such as jellen, gum agar, those types of things. And researchers have looked to apply these bio polymers to soils to enhance the mechanical geotechnical properties of the soils. And when you think of xanthan gum, I tell people, if you haven’t heard of it, if you eat yogurt, go and look on the back of that yogurt container. And xanthan gum is usually used in the food industry as a thickener for certain foods you have given a thicker appearance or to enhance the thickness of that Food with these bio polymers, they also have an impact on soils. Because these bio polymers, once they’re wet, they sort of are like sticky. And so they can bring a non cohesive soil, we typically think of saying together enhance the stabilization of those non cohesive soils. The reason that they’re biopolymers is in the past, people have used amendments to do this. But those amendments have not been as eco friendly or environmentally friendly biopolymers, that they’re going to be biodegradable, and are thought to have very little effect on the environment. So that’s where the interest comes from, with these biopolymers. Again, if you look at some of the previous methods that were used, such as semen, things like that, you emit a lot of co2 in the production of x. So, from that perspective, there’s a lot of interest in these bio polymers for enhancing soil stabilization. The project that we have is understanding how these bio polymers enhance soil stabilization, or some of these chemical properties of the soil. In order to understand how it enhances those properties, you have to understand how it would enhance or affect some of the physical properties, such as water retention, water movement in soils, the thermal properties in soils, to me, it becomes very important to understand those also in order to get a better understanding of its impacts on the mechanical and geotechnical.
BRAD NEWBOLD 36:31
You’ve talked about some of these biopolymers being biodegradable, as they degrade, does that then also degrade the stability of the soil that they’ve been interacting with?
DEDRICK DAVIS 36:40
Yes, it could grade to the stability of the soil. I think when it comes to this, from what I’ve seen, there hasn’t been a lot of research on how long the stabilization holds up to the biopolymer being applied. And I think that is where one of our other faculty members here is actually looking at the stability and how long is it going to be stable in that soil? That is a very important question. I know from some of the preliminary experiments that we’ve seen by this biopolymer to the soil, but over time, you can see some changes in the soil as we go through repeated measurements with the same soil samples. So there’s some some questions there about how it degrades after you’ve applied it.
BRAD NEWBOLD 37:21
In our last few minutes, we want to kind of switch gears and talk more on the social side of things when it comes to being a soil scientist. You’ve gone from Alabama a&m, which is a historically black college or university, you moved to Iowa State, and then back again, can you talk a little bit about your experience when it comes to diversity within the sciences, and what you’re doing currently, or what you have done to help improve diversity within ag and Soil Sciences,
DEDRICK DAVIS 37:50
the example of going from Alabama leading into Iowa. And I will admit to you that was a big shock. Because two very different environments, I think when it comes to understanding the value of this to diversity is very important, because I think students have to have an idea of how to operate in all different environments. And being an Alabama was in a course in a historically black college university in a predominantly black student population. So it was something that I became used to, but then going to Iowa State got me out of my comfort zone, because it’s a totally different environment, predominantly white institution, Alabama a&m 6000 students, I will state when I left I think was right around 30,000. So even navigating that whole thing is pretty important and can enhance the student with certain skills. And I think being able to operate within those different environments becomes important. But also to I think it speaks to the importance of knowing your different audience, and how to get along with those different audiences. What I did at Alabama a&m university, I couldn’t do at Iowa State, I was very comfortable at Alabama a&m, not comfortable at Iowa State. So that forced me to get out of my comfort zone and be proactive, and getting to know people. So I think that is very important when it comes to my own research group and the diversity in it. I tried to have a diverse research. And when I say that verse I mean nationality, racial diversity, and it’s something that I’m proud of, because in my research group right now, we have African American students, a few Indian students, a Haitian student, just joined. We also have a Chinese scientists. We have a Jamaican student, and even though a large number of us are, what we would consider black, just being from those different countries brings diversity there and difference of opinions that I’ve really grown to appreciate. I think also too, by having this diversity in my group has helped us to consider how we communicate with one another. Because the norms of one culture are not going to be the norms of another culture. Yeah, so you come to appreciate that. And I think my students have come to appreciate that. Also, over the last few years, as we’ve grown in number and as we’ve grown in diversity, and I look at it as actually preparing my students for what they might encounter once they leave Alabama a&m. So it’s very important to me, and then I think, also to that other diversity piece. Because students once they leave here, the world is not going to look like Alabama a&m. So I tried to take advantage of every opportunity I can to get them away from Alabama a&m and put them in a, in an environment that might be more of a reflection of what they might encounter once they leave Alabama a&m. So hopefully, they’re getting the best of Alabama a&m, but also the world.
BRAD NEWBOLD 41:06
We’re out of time here. But is there anything else that you would like to add? What is what does the future hold for your research? What are you excited about here in the next few years?
DEDRICK DAVIS 41:16
I think I’m excited about from a research perspective. For one I like the different projects that we have going on, they’re very interesting to me from build the lab study. And they have different applications were working in soil health, which in my opinion, is very important because to me, everything starts with the soil. Soil Health provides us the ability to take a holistic approach to a route to improving soil, I think that is important, we have to consider not only the chemical or the biological, or just the physical by itself, we have to consider it all together. And being able to take that and apply it to something that is important for the state of Alabama, such as cotton production, to me is very important. So it shows that what we’re doing is important on a local state and national basis, but also to when it comes to the project, such as the one with the biopolymer, being able to have an understanding of how these bio polymers impact. Soil physical properties and processes is going to be important because it’s going to help understand how to utilize these bio polymers to enhance soil stabilization for let’s say, the Department of Defense or for the army. So being able to see the application there is what I’m excited about, as we take on these projects. And as we do more and more work, being able to see the growth in the students and being able to see the growth in my research group. And the interesting individuals that come into that research group, which I’m appreciative of, is something that I’m excited about, because it goes from a point of where we’re training students, but then eventually, as the students progress through their program, they started training me on what they’re finding, and that is what I get excited about when that I guess when that switch takes place. I’m not the lead, but they’re leading me. And for the PhD student I have that is what is happening right now. And every day I get excited about that. And it keeps me coming back here to see what she has to tell me to see what she’s learned and to see how her thinking progress has progressed. And those are the things I’m excited about going forward.
BRAD NEWBOLD 43:41
All right. It looks like our time is up for today. Thank you again, Dedrick for joining us and sharing your research and being able to talk with us today. It’s it’s really been a very interesting, fascinating conversation.
DEDRICK DAVIS 43:53
All right. Well, thank you, Brad. Thank you for the invitation. And I’ve enjoyed this.
BRAD NEWBOLD 43:57
Stay safe, and we’ll see you next time on We Measure the World.