Transcript:

BRAD NEWBOLD 0:00
Hello everybody and welcome to We Measure the World, a podcast produced by scientists for scientists…

ERIN BROOKS 0:07
But the interesting thing is we finished a project we put cover crop in instead of fallow, we broke the field into thirds. And we looked at the winter wheat crop following that. And the idea is well, the cover crops section, the field will actually have more water stress on the winter wheat. So the winter wheat yields after the cover crop should be lower. It just happened we had one of our biggest droughts after this cover crop experiment. And I started looking at the response the cover crop, the winter wheat have the cover crop was more vigorous, you could actually see it in the satellite imagery quite clearly that NDVI was better and responded sooner. Those soils that are more organic, carbon rich, they’ve actually they have more cover and they they’re more resilient to heat stress, they probably infiltrate more water, so they probably actually even though you might have a crop growing, they might have more infiltration, and they might more resilient. Those soils might be more resilient, particularly in extreme years.

BRAD NEWBOLD 1:04
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 Erin Brooks. Erin is an agricultural engineer and professor in the Department of Soil and Water Systems at the University of Idaho. He obtained his Bachelor’s in Agricultural Engineering with a Soil and Water Engineering emphasis at Washington State University, and then went on to get his Master’s from the University of Minnesota and Doctorate from the University of Idaho, both specializing in Hydrologic Measurement and Modeling. Erin’s current research focuses on the management of ecosystems through the combination of field experiments and modeling. And today, he’s here to talk to us about his work in the fields of hydrology, environmental engineering, and agricultural engineering. So Erin, thanks for being here.

ERIN BROOKS 1:57
Thanks for having me.

BRAD NEWBOLD 1:59
So today, we wanted to talk to you about all of your various research interests. But definitely we want to start out with your background. And we want to know how you got into this this intersection between soil science and hydrology and modeling.

ERIN BROOKS 2:12
Yeah, thanks. Yeah, so I was growing up, I was actually had a lot of exposure to both my mom and my dad’s side of the family had both agricultural and forestry backgrounds, we both have farms, and my uncle was a dairy farmer, which really kind of got into agriculture. And my dad was a math teacher and had the summers off. So I just got this love of agriculture. And my mom said, Don’t go on a dairy farming because you’ll never get married, and you’ll be tied to the farm. So I figured I was good at math, and like agriculture, got me into ag engineering, and really kind of that background, I think, really drove me to I really want to be connected with practical agriculture and forestry. I love you know, fly fishing, hiking, I love that nature. And for me the passion of what I do is really applied science trying to take science to make agriculture, forestry, some of these industries economically viable. At the same time, We can do this in ways that preserve the environment and preserve and make what we have here sustainable and actually available to the next generation. So that’s kind of the my research really applied research trying to make decision support tools from modeling side of things and haven’t really well grounded in and the landscape itself.

BRAD NEWBOLD 3:28
Right. So was there any other specific I don’t know, triggers, or, you know, crossroads where you’re like, I should go, I should go this way. As opposed to that?

ERIN BROOKS 3:38
You know, I got hooked up early on at Washington State University. In bean a g engineering, I worked a lot with Claudio Stockle, who was at the time actually working with Gaylon Campbell, on several projects in developing a crop sys model, and I just got hired on as an undergraduate just to help out his research projects. And it was just fun to go out. And at that time, looking a lot about evapotranspiration in the field and using instruments to track that and a love for research and found out you know, once you graduate, there’s research assistantships out there that actually pay you to continue to do this and, and so I kind of got fell in love with this idea of this, you know, experiments and applied research to solve problems. So that’s kind of what kind of drove me into it. And I think, for me the direction it took is really, when I got my master’s and I spent a couple years at Cornell working with New York City’s drinking water supplies when GIS came out, and so geospatial modeling and targeting prioritization. And I continue to do that with some of my models as let’s target where the pollutant load is coming from. And oftentimes we talk about 90% of pollutant load comes from 10% of the land or 90% of the pollutant load comes from 10% of the time, and so really, we have a lot opportunities to target management to get the biggest bang for the buck. And really here again, getting back to the supply and sign.

BRAD NEWBOLD 5:01
Well, I think one of the one of the cool things about having you on is, for our podcast, we like to hit lots of various, you know, subjects, we have a broad, diverse audience who are doing everything from civil engineering to agricultural research or, or even, you know, farmers and growers themselves. And you’ve touched on a little of all of those. And so I think first, maybe we can hit the your research into water balance studies, and kind of what got you into that and what you’re looking to solve there.

ERIN BROOKS 5:33
Yeah. So originally, like, I start getting into environmental problems, the first thing you look is in the stream, your night and you got some pollutant load coming in. And when I was in New York, it was looking at phosphorus loading or actually Cryptosporidium, here on the Palouse, it’s still nitrate loading. Sediment loading has always been a big topic here. And so when I got into this is a lot of understanding studies where we actually put instrumentation in a landscape to understand not only the what’s coming out of the outlet of whatever catchment or watershed or even field, but actually where it’s coming from. Because if you want to start doing geospatial targeting, you want to know both distributed response, where it’s coming from and what’s at the outlet. And so a lot of my studies have, a lot of them have involves streamflow measurements or edge of field runoff measurements, and then coupled that with point measurements, targeted measurements in the landscape where the soil moisture or water level perch water level fluctuations. And so one of the projects is kind of, I’ve been really excited in the last several years, I work here with the USDA ARS and Pullman on a project on what’s called the Cook Agronomy Farm, and this is the LATR site, the long term agro ecosystem research site. And USDA has really invested a lot of money into long term studies, and we want to look at long term impact of our soils are changing, pH is changing, organic matter is changing. And we’re changing the way we farm. And so there’s really important to have long term monitoring. And so one of the projects I’m really excited about now is a project out here just a couple of miles from here, halfway to Moscow, where we put in some surface flumes, to look at surface runoff, we actually have flumes that we’ve put in on drain tiles or subsurface drainage around here and and then also, we put in weighing precept gauges and soil moisture sensors. And then we have some paired catchments out there that we’re looking at no till versus conventional till where we have eddie flux tower measurements. And so really, when you start thinking about trying to solve and understand water problems, it’s really that water balance, you want to get at In this case, if you think of water balance, input, output change in storage, we got presept coming in, we kind of get a good handle on that. We have outputs in ET would you have a good idea that we have subsurface drainage, we have surface runoff. And probably the only thing that really the remaining component is deep drainage, which is kind of hard to directly measure. But there’s actually tools that use some of the some of you guys’s passive drain gauges to actually look at deep drainage to some extent, as well. And so it’s really been a great there’s a lot of investment at the ARS and putting even AC power out there, which opens a lot of doors to actually one of the challenges of field monitoring is your flumes have ice in them, they freeze up. And so we’re able to buy some flumes actually have heat tape in them. So they actually, when a storm events happen, in diurnal cycling, we have freezing at night, actually thaws the flume out. And so it’s been really great to actually see these parents sites and actually have all this together to really look at that water balance. And I know that ARS continues to see that more long term focus on water balance type studies.

BRAD NEWBOLD 8:51
So with when you’re when you’re, I guess, trying to try to measure that water balance flux, what are some of the particular I guess, measurements that you’re looking at? What are the you know, the inputs to that model?

ERIN BROOKS 9:04
Yeah, so like say, well, for flume measurements, a lot of it is water level sensing. So I like flumes, because they’re structures and don’t worry about other rating curves so much. And so trying to have some sort of water level sensor that’s reliable. And I’ve gone through actually, either pressure sensors or bubblers and USGS administering uses bubblers to do that. From the precip measurements, and here we have a lot of snow. And so we done using some of the weight and precip gauge products, but we’ve also used some of the products that you guys have kind of come up with and in some of the atmosphere type of measurements that we’re using for the precip side of things. So you tie in water quality on this. So then we also then would tie in an electric conductivity measurements, and we actually with the water balance, we can actually tie Those pressure sensors into a data logger, which then we can use triggers to do water sampling. And so we have auto water samplers so when a storm event happens, it’ll trigger this water sampler. And so we’ve used different brands of these water samplers to kind of get at this event based sampling.

BRAD NEWBOLD 10:19
I mean, you mentioned you mentioned dealing with water quality there. So where can you get into a little bit more detail about some of the projects and research that you’re working on?

ERIN BROOKS 10:26
Yeah, in that realm. Yeah. So a lot if you’ve been on the Palouse, and come visit, if you haven’t been there, we have a very unique landscape. There’s a lot of topography. And we’ve had historically a lot of erosion, probably one or two, the most erosive landscapes around the world in terms of topography, especially in the 1930s, where farmers came in and started tilling the ground using moldboard plows plowing up and down the hill, burning their residue. And so we have some of the massive erosion. And so we farm now a legacy of erosion, which has removed topsoil, which has made our toe slopes full of organic carbon, which is great, it’s nutrient rich, but our ridge tops are pretty depleted. And so the question is nutrient management. How does a grower go in and actually farm landscape this so variable, and we haven’t done studies to kind of using soil moisture measurements and some of the models to actually say, actually kind of classify the landscape as ecosystems. And you really can kind of think of a toe slope and the Palouse is almost like farming a humid landscape, it’s, you know, the water table could be within a foot of the soil surface, well, half the year, there’s really just so you got this humid environment, then you think of ridge tops, they’re really dry, they don’t store a lot of water, and they’re windblown the snow gets drifted off. And so it’s more of an arid environment. So if you think of think of farming, so one of the things the Cook Agronomy Farm was set up to do is actually look at precision agriculture. So how do we vary fertilizers so that we optimize nitrogen, so that, you know, we’re not leading to water quality problems or from a greenhouse gas perspective N2O measurements. And so in the process of converting to no till so we’ve done a conversion to really low impact tillage which has reduced erosion down, but it has nutrient impact as well, the soils become more structured, you have more preferential flow. And a landscape where we have drain tiles, you can actually have a water quality, you actually increase your water quality and the soil becomes more organic rich is more nutrient rich, and the microbial environments actually breaks down that nitrogen into nitrate, and then you start having more water quality problems. So essentially, as these landscapes change, we need to understand how to management just good ways. And actually, we can actually reduce our synthetic fertilizers down. And so one of the projects we worked on and actually was early on when you guys were bringing out your passive drain gauges, we said wow, it’d be really great to understand nutrient fluxes and particularly in these no till soils. And so we actually put in one of these drain gauges out in the landscape up in the Cook Agronomy Farm. And it’s interesting. And I have a paper that will show this as we put these drank gauges in which you take an undisturbed core and then and pull it out and you put a coupling on it, and you can put the reservoir underneath it and the pipes come on up. So you can sample that leachate underneath. We took that core and pulled it out. And they were as I think we kind of 36 you know, Pinky sized macropores, I was just amazing. The preferential flow that’s going on in here. And so then we end up doing is we would measure it throughout the year and say, Well, how much what’s the flux coming out, and what’s the water quality coming out of it and some of the nitrate loading coming out of these, you know, typically the streams around here we get 10 to 20 milligrams per liter of of nitrogen, we are getting up to 50 to 100 milligrams per liter. And so we could certainly see that not nutrients coming down. We actually did a rainfall simulation on top of it trying to look at preferential flow. And what we found was really interesting, we had soil moisture probes in this core. But we started raining on it, we actually see bypass flow going on, we actually water was bypassing or the soil moisture was not wetting up but actually getting fluxes down at a five foot depth before we actually see this wetting front completely fill up the core. So that was really enlightening. And those first pulses of nitrogen were just really hot in terms of their nitric concentrations. So really kind of using that, wow, we actually had some of these landscapes, the structures changed the nutrients dynamics has changed. And that’s going to affect our nutrient load. And it really does open up opportunities for growers to really get into well, I can actually drop my fertilizer the time in the fertilizer, right, and that sort of thing is going on.

I think that’s yeah, that’s super important. So where are those macropores basically from? Are they wormholes are they is that root holes? Is it all of the above? You

know, it’s interesting, and you can actually see some of the pictures is the the a lot of those macropores actually had a route going right down the middle of it. And it’s kind of known this, this drill sphere is what they kind of held the environment around e macropore is really nutrient rich. And so yeah. Worms. Is that a legacy of a long time? They’ve I mean, if you hear the stories around here next to this true right here beside it, it was one of the key ones as this giant Palouse earthworm that’s around here. That’s. And there’s actually papers documenting these wormholes going down hundreds of feet down there, there’s actually could be a major groundwater recharge. I don’t know exactly. But it looks certainly like they’re wormholes and they’re going down. I don’t know the timing of it. But that’s it.

BRAD NEWBOLD 15:37
That’s wild. I think and also, just just the fact that, like you mentioned, the fact that flow is bypassing the soil moisture sensors, like they’re not reading that flow. But yet we’re getting it down, you know, in the in those drain gauges and those kinds of things. I mean, is, is that something that is particular to what you were looking at? Or do you suspect that this could be happening in other similar agroecosystems?

ERIN BROOKS 16:08
Right, I think that the rates that we were applying the rainfall at would be more of a, like an intense storm. And so I think those macropores trigger when the moisture kind of gets high enough. So I think if you are an irrigated person, if you’re applying water as fast as you can, which most people do just to get the water in there, it’s possible that you could have bypass flow it’s going on and it’s which, you know, my background is looking at water quality from watershed perspective, is can be really frustrating, then it’s like, wow, how do we model this? How do we capture this? Which kind of, actually, in the last 10 years, I’ve worked a lot with Dave Huggins and some other agronomists, which we started to use remote sensing, to actually from remote sensing and DVI and dairy indexes, you can actually see nitrogen content in the crop, which I said, Well, how many different of these draing gauges do I have to put in a landscape to actually document a nutrient load? Yeah, it’d be great if somehow, we can actually look at it from a different perspective. And so I started thinking about nitrogen removed by crops. And really, if you like, start thinking the nitrogen in the soil, our biggest input is our fertilizer. But if we can actually map the output to actually the nitrogen go into the crop, while there’s not a lot left, that it’s really dependent on the water flux, and what’s the conditions of the soil, but boy I can get, I can actually start plotting nitrogen use efficiency, and so I can start seeing, okay, and this is an index we use with with a lot of farmers now it’s like, here, we can actually see how much nitrogen removed from your winter wheat crop or your cereal crop. And then this is how much you apply and you just divide the two; removed versus applied, and you have a nitrogen use efficiency index, and you start then start analyzing your, your field after a growing year, it’s like wow, boy, on those, those ridge tops, where they’re all poor ground, I’m only using 10% of what I applied. And they’re really interesting. So I think some of the remote sensing tools and and we’ve kind of worked with you guys a little bit on your NDVI sensors. And I know you’ve gotten some of the Apogee sensors now, we had some of the SRS ones before. And we’ve actually put those on center pivots and irrigated areas. Put those on, and actually, as the center pivot goes around, we’ve actually seen changes in the and the crop response, trying to understand nutrient uptake. And so you kind of started looking at problems from Hey, well, for remote sensing tools can really start telling us insights, if I actually finding my landscape now, because I do variable rate fertilizer is having uptake efficiencies above 50%, or 60 to 70%. Ultimately, hopefully, the water quality issues go away. And so this kind of started like, okay, I can work with these other guys and really try to understand the landscape and a different aspect.

BRAD NEWBOLD 18:50
You’re talking about remote sensing, have you ever backed out we’ve had some some folks on here, some guests who have talked about, you know, working with drones, or even satellite imagery. Have you got into that in into yourmodels?

ERIN BROOKS 19:03
Yeah, we recently hired someone Dr. Johnny Lee in our department that really does a lot of drone imagery and using artificial intelligence to try to analyze data and to extend to analyze patterns and looking at different wavelengths and what they tell us. From a practical farming perspective, and I teach a precision ag class, satellite imagery, it’s instantaneous, it covers in some of the imagery now is 10 meter resolution comes every five to 10 days. So from like a nutrient management perspective, I say satellite imagery is actually actually a good tool. It doesn’t document the why or in detail of that doesn’t have the resolution to document disease, stress, and I think what we’ve been looking at is using drones to actually fly those a couple times in your field and a lot of times your patterns in your field are consistent which in for for managing a farm, you want to look at consistent trends. actually taking drone imagery combined with satellite imagery has understood that it helps explain what’s going on in your field to helps link the two and actually helps scale up. And so that’s some of the things that we’re looking at is how do we use drone imagery understand these patterns are very smaller scale, then have that direct maybe soil sampling or direct some tracking to say, what can we investigate what that is, and then then help us interpret the satellite imagery. We can use more for more yearly, or even ease in season management of fertilizers or some herbicides or something?

BRAD NEWBOLD 20:39
I think that’s fascinating. I mean, we could go on all day about, but I did want to kind of kind of back out because you’ve talked a lot about your, your work with modeling. And, and like we mentioned, we have people doing all sorts of diverse research. But also just, I wanted to ask you about about finding the balance between doing the field work, and the modeling itself? I mean, we have, we have people, there’s traditions of being heavily reliant on one or the other. And I just wanted to know, like, Yeah, how did you How do you find that, that that proper marriage between the two?

ERIN BROOKS 21:12
Yeah, yeah. No, it’s, it’s one of the things I really stress with my grad students is this balance, and I really have to impress upon them as doing both, I would love to have a project where they’re actually out in the field, they’re looking at structure, they’re looking at actual reality, and understanding spatial variability and understanding these preferential flows. And, and really saying, Oh, wow, these, this is the process. I also want them to do modeling, because, you know, essentially, in the end, if you can be experimentalist, and it’s great for research, but if you’re a practical applied, you’re gonna do problem solving, we just can’t measure everything, there’s just no way we can get at it. And, and so you can start, be experimentalist is like, at some point, if I want to make impact, I need to go to a model. And so that kind of gets you into the modeling side. But then you can get into that pit where everything’s a model, I’ll take whatever model off the shelf and apply it and a lot of models aren’t appropriate. So having a background of actually this is what I see, this is how I see runoff for soil moisture, something going on. And that model is really not appropriate for that. So having that create, actually some more critique and some understanding what’s going into a model to help you select that model. Models, they can apply them almost anywhere, a lot of the the tools and the data we have available, there’s really great geospatial modeling we can have. And then you can fall into that trap that, well, we can do all this in modeling. And but if you’re a field experimentalist use, like there’s no way a model can predict this, there’s no way that a model could capture all the spatial variability I see out here. And so, you know, this idea and I try to impress upon him in my modeling classes is, you know, all models are wrong, but some models are useful, right? So how can the data we collect from Experimentals help us parameterize and get that improve the accuracy of the model? And what’s the interesting thing is when I start doing modeling, I tie modeling back into, well, we think this pattern, the model is saying this pattern is happening, do we see it in the data, and using the models actually help interpret the data kind of feeds back on itself. And so this is I think it’s a kind of a cycle to feedback and experimental to understand reality, spatial variability, uncertainty, then helps us communicate our model results. Because, boy, if that model is going to predict streamflow to the 1000th decimal point, there’s no way it predicts that well. I know the reality is the variable isn’t then the feedback, the data. So

BRAD NEWBOLD 23:33
Yeah, I think I mean, do you have any, any rules of thumb when it comes to, you know, model creation or determining success of a model? I mean, there’s, there’s statistical tools that you can use to, you know, to gauge the success of a model. But, but a lot of times, I mean, sometimes you can, you can visually, or you can understand, we’re getting diminishing returns with this model, we’ve got too many inputs, too many parameters, we need to kind of dial it back.

ERIN BROOKS 23:58
Yeah, yeah, no, um, there’s a lot of amount of models out there. And with AI and some of the data on Linux, you know, you can take whatever data stream and the model is even know what, what it is. And you can put some statistical analysis and try to simulate what’s going on. That’s great if you have one location with a lot of empirical data, and you want to continue to do empirical data at one location. So it’s almost taking data. But to really understand well, well, how does climate change, well, what is actually converting to to no till going effect in the long term, a lot of these processes that you need to have almost a scientific understanding. So the process based models, some of the process based models can get into really detailed too. So I’m looking at air entry potential on a very specific part of a landscape where we don’t even know the soil variability, that information is not there. And so you can have models are just over parameterized. What I found is some of the more simpler models actually can do a lot of that variability. They’re understandable to actually stakeholders, and they are providing and a lot of times all what stakeholder want to have problem solving is red, yellow, green is it higher risk here, lower risk there? Spacially is this more or less. And so sometimes we get caught up and chasing the NASA clip efficiency or the R squared or whatever. And from applied side, they just need some advice. And I think there’s a lot of weak that these tools can provide. I’m doing a lot with wildfires, right now, doing some wildfire modeling, where we’re taking geospatial models, and we can upload burn severity maps, and we can work with Portland for a long time. And just last week, last two weeks, the drinking water where the Bull Run watershed where the Portland gets their drinking water is burning now. So there’s now there’s this risk of a pollutant load coming to the drinking water reservoirs and all Portland gets their water from an unfiltered water source. And so if we now have ash and sediment and water quality come into this reservoir, they want to know, what do we can do now. And one of the things you can do after a fire is like you put some mulch or wood shreads on what we get are the models that can say we can tell just based on soils in the hydrology, this is going to be a high risk of erosion, fly on some wood mulch here. I mean, that’s something you know, and if you don’t have a certain amount of money, this is the targeted prioritization approach. And then we can then come back on more of a probabilistic approach and say, we can run it through 100 years of weather data and actually get well, there’s a 10% risk, that the sediment load coming out of the reservoir is going to be at this level. And so we can actually get probabilistic output. We don’t have to be absolute. We know our models can’t be but then it gives them a ballpark and they can make decisions based on that. And so yeah.

BRAD NEWBOLD 26:45
I think I mean, there’s, there’s pros and pros and cons to, to, like you said, dealing with stakeholders who may not be in your scientific, you know, specialty, or even in any of the sciences at all, like you’re talking about policymakers and other other groups like that. What are the some of the things that you’ve learned as you’ve worked with these interdisciplinary groups on these various projects? I know you’ve worked on on projects, with landscapes in transition projects, where you’re dealing with all sorts of different researchers and scientists who have their different specialties you’re working with. Is Portland, a project where you’re dealing with people who are not in the sciences at all? Where are some of your learnings and findings from your own personal experiences in those?

ERIN BROOKS 27:24
Yeah. And a lot of it for a while, and there’s still a term that’s going around is best management practices? What are the best management practices? And a lot of times, we’re going into a watershed study, what’s the best management practice? And we can, you and I can use these tools and I can put in, I can say, Yeah, this is the spot we need to do. This is a high erosion spot. But a lot of times I talk in my water quality class is best management, also social and economic. There’s other factors out there that might prevent someone from doing something. And so I think we need to take this holistic view of, okay, what’s possible. And we could go in and say why that part of landscape should adopt this. Well, this might be someone, someone in a farm or three farm and some poor ground is not making a lot of money doesn’t have the capacity to respond to that. And so it might not be the perfect solution, that’s the better solution might be working with someone else maybe has maybe not as a relative of land that maybe has the capacity to do that. And so really understanding the culture of the people that you’re working with, what limitations that they have, like nutrient management. You know, a lot of times they’re, they’re farming big lands, or they don’t have the capacity on the actually machines to do some of this. And so trying to understand, man, I love working with the farmers, you know, oftentimes I’ve project I feel like I learned more from the farmer than then I give back to him or her. And so this, the more we can understand, well, this is the limitations I have. And this is what and I can come back with my science based solutions and say, Okay, well, let’s work together and understand that dynamic. Another example is, I teach an irrigation water management course. And a lot of times you’re thinking about irrigation. We have tools we have so moisture sensors, we have water potential sensors, we have weather stations, we can predict evapotranspiration, so, and then you do surveys of the irrigators, and like how many people are using that sort of information to irrigate from irrigation scheduling? There’s very few. Yeah, that’s interesting. It’s like, why aren’t people using some of these great technologies. And then I want to start having more, you know, I teach to existence management, which are more applied. A lot of the kids in my class actually come from irrigated farms and, and they start telling me, you know, our center pivots have a certain capacity to apply water, we can’t instantly apply water over our entire field. We’re only applying water to maybe 5% of the field at a given time as you pass it down as your pass to this is guess what irrigation scheduling I turned my center pivot on in June and I don’t turn it off till August and I’m still not meeting my crop water demands. And I started, okay, so irrigation scheduling to person with a center pivot, they have some limitations. And so really the irrigation scheduling maybe is and what I, I do believe and I have a grad student working down in southern Idaho working with people on water quality implication of over irrigating is, we can make a lot of ground in the spring, there’s a lot of times that growers are overapplying in the spring or losing some of their nutrients, we can actually become more efficient there. And that’s where I think we can target growers with some of these tools, and some moisture and so wasn’t till I started getting an interaction with people. Okay, so the solution, this is where we need to target our tools and how we can reach out to stakeholders.

BRAD NEWBOLD 30:45
I know you’ve also mentioned that that you’ve worked with so in particular, we can stay with with ag and with with crop management practices. You’ve talked about working with no till I know you’ve done some work with with studying cover crops and other things like that. Especially can you talk about cover crops? We haven’t mentioned that. Yeah, some of the interesting findings that you’ve been getting there.

ERIN BROOKS 31:06
Yeah. So you know, the just recently, in the last year, university, Idaho got a $55 million Climate Smart grant, which I’ve been asked to, to help lead with Dr. Sanford Eigenbrode over there, which is a real challenge. But a lot of the project is incentivizing growers to do more sustainable practices, and really, for motivation from a soil carbon perspective, increasing soil carbon and reducing greenhouse gases. And so some of the practices that we really want to increase in carbon is cover crops. There’s a lot of great testimonials from the Midwest where they’ve done some really good cover crops put in and that’s been really successful. Here in the Palouse our landscape, our climate is different. You know, we we don’t get any rain in the summer, which is good for dryland I guess, just we don’t want to have too much rain, we’re harvesting wheat. But it prevents with doing some of the fall seeded cover crops and so but there’s so many growers out there, they really see the benefits of cover crop diversification and trying to build up their soils again. And so there’s a lot of people investigating. So this was this landscape and transition project we’ve done and actually looked at different climate zones here in the Palouse. We’ve put cover crops out in places where typically have fallow so now they’re growers to the point where they’re really willing to put a cover crop in instead of fallow. Which is a risk because that’s their water storage for the next crop. And so trying to document some of this. And so that’s what we’re, you’re looking at this project it can we get people to adopt cover crops. And so one of the practical tools and ways we’ve been trained to help growers and adoption of this is, well, each year is different. If we have a lot of June rains, you can keep that cover crop going. But the question is when do I terminate it? And so that’s just one of the things that we’ve been working on. I currently have a Western SARE project I’m working with Dr. Sanford Eigenbrode as well as actually looking at termination of cover crops. And that’s one thing, I think soil moisture probes and actually, irrigation models. So soil water models, we can track soil moisture pretty well in this landscape. And I think cover crop termination has a lot of great opportunities for us to help decision support on those. But the interesting thing is we finished a project that we put cover crop in instead of fallow and we broke the field into thirds. And we looked at the winter wheat crop following that. And then the idea is well, the cover crops section, the field will actually have more water stress on the winter wheat, so the winter wheat yields after the cover crops should be lower. It just so happened we had one of our biggest droughts after this cover crop experiment. And I started looking at the response to cover crop the winter wheat of the cover crop was more vigorous, you could actually see it in the satellite imagery quite clearly that the NDVI was better and responded sooner. And one of the things I think potentially could be happening out here we need to understand it more is those soils that are more organic, carbon rich, they’ve actually they have a more cover and they they’re more resilient to heat stress, they probably infiltrate more water so they probably actually even though you might have a crop growing they might have more infiltration and they might, more resilient, those soils might be more resilient particularly in extreme years. Flood years drought years on a common year you look at, we’ll say no till versus conventional till or cropping system more diverse was the other I think the yields are pretty similar. But I think you know in terms of we talked sustainability going in the future climate change, how we store our soils, I think some of the things we’re going to start seeing more and more on these more extreme years and so yeah, I’m pretty excited about how do we get cover crops to work. When do we plant and when we terminate them and just love to see that the growers are hungry for solutions, they really want this to work. And so hopefully the next five years of the project, we can start, you know, coming up with some solutions. integrate that.

BRAD NEWBOLD 35:10
I mean, that’s one of those things where, and we’ve mentioned this before, is that is that when we’re dealing with with growers is, yes, there’s traditions of how to farm and those kinds of things. And maybe they’re, you know, stereotypically slow to adopt new practices and that kind of thing, but at the same time, it’s, it’s, it’s our human nature to do that, that cost benefit, you know, that risk assessment and say, just mentally, how much of a risk? Do I dare try this new thing? And then, you know, what if, like, our models could say, oh, yeah, you’re gonna have 60% success, you know, over the 100 years that we’ve been running this model. But that’s, that’s a, you know, that’s, that’s a median value. And that’s not necessarily going to say, hey, you might have these extremes where you’re gonna get nothing. Or you might have, you know, definite success, and you’re, you know, going to double your yield or those kinds of things. And so, yeah, being able to, I guess, my question then would be, how have you been able to communicate with, with those, with those growers and others to really, to really help them see the potential benefits for implementing these practices?

ERIN BROOKS 36:15
I think one of the things that’s really changed, and I talked about this in my precision ag class is the historic imagery, the historic satellite imagery now that we have, we can tap into the last 10 to 15 years of, of what’s going on in a specific field. And so what I like to do is talk to my students about is let’s, let’s look at the temporal stability. Let’s let’s look at a lot of times I look at it field scale variability, let’s compare the average number of NDVI on this part of the field versus what the average is for the field. And then I just go back in time and say, is this consistently always lower, as consistently higher? And what was the best year versus the worst year? We start seeing that. And I think with that, understanding the grower can come in and be realistic about well, yeah, I understand. One year, the next year, it could be feast or famine. But from a profitability perspective, should I still fertilize to that great year, every year, or should I drop my rates, just to say this is my realistic yield goal, and actually, in nine out of 10 years, I’m making more money, maybe that one year, I’m gonna have nitrogen stress on that part of the field is so trying to get maybe a temporal analysis to help. Some of this, you know, growers are hungry all the times growers adopt a new idea, and they do it the whole farm, it’s like, if this works, I’m gonna do it the whole farm. And what I encourage is, with remote sensing, some of these tools, always be a learner. Set aside, so there’s so many opportunities to onfarm experiments, and I say, try it, do a trial, and convince yourself and do it over a couple of years. And try cover crops on a part. And so it’s not as high risk, you’re going to learn from that and then slowly expand. And I think that’s where research universities, I’d love to see the universities become more engaged with growers and some of the things with this new project, we’re going to make this we’re developing essentially a geospatial farm management tool that we can use to, from a research perspective, to upload our soil sample points or some of our water quality things. But they actually can access some of the analysis we’re doing with the models, and then some remote sensing data that we can do that maybe they can’t do, and maybe then have them be able to, you know, go into a tool and help us work together. We can learn from them. This is what works and what doesn’t work. And we can then demonstrate very quickly what worked last year. A lot of times the universities have a reputation of oh, you got this mod this money. I use my field and I don’t hear from him for five years. And I think we need to become more engaged with growers. And that way is let’s No, no, no, we have tools that we can come in and learn along with them. And I think that’s an there’s a lot of growers that would love for us to engage in that way. And cumulate growers know, they know the good years, they know the bad years, and I think talking to them realistically about that, like using some of these tools is a good approach.

BRAD NEWBOLD 39:22
Yeah. I was gonna ask, Have you tested different types of cover crop? I was thinking, I mean, there’s different, there’s different types of cover crop, you can talk about forage, you know, cover you can talk about or like green manure or you know, how you manage that cover crop itself.

ERIN BROOKS 39:37
Yeah, yeah. So some of the people you know, we have a dramatic climate gradient, and so people in near Moscow have, you know, 25 to 30 inch precip zone. Really cover crops to them, really a real big benefit for them is actually growing a crop even during the winter fall, see the cover crops because we just have so much water and they’re trying, let’s use cover crops as a water management strategy, just take some of the water out. Also it takes that nitrate out and converts into organic matter. And then essentially then as it breaks down in the next year, then it releases that nitrate back to the, to the, to the crop when the crop needs it. And so I think from that perspective, yeah, okay, so it’s a fall seeded a cover crop, we want to get it in and we have the water out there probably could get it in pretty easy, a lot easier out there. And so that strategy is okay. It’s a fall seeded the crop, I can’t have annuals that are going to, you know, not resist the frost. And so then selecting winter peas or something like that can endure the winter. In the in in the dry areas right now it’s water managed. Kind of the example I described before is like, you know, it’s really hard to start a fall crop, the soil is completely dry germinating, anything in the fall is difficult. The only reason we do winter wheat is because it comes out of fallow, and there’s a lot of moisture there after the fallow. So in that drier, it’s made of a spring cover crop that they can go in and they can do it during that fallow year. And then the challenge is the cover crop termination. And so varieties, how many different types? There’s mixtures! I don’t know, I have a good understanding. I think there’s so much benefit to crop diversity. And I don’t think we completely understand it. There’s some crops that work well together having the legumes with the cereals with the brassica. Somehow, there’s certain combinations and and the project we looked at with Sanford Eigenbrode and his students really saw under winter peas somehow winter peas with arthropods respond to it that macker, the pollinators, the insects, the all this actually responds to it in a really good way. And so I think that’s the science that I don’t know.

BRAD NEWBOLD 41:56
I know. That’s what how do you model something like that? Okay, we’re gonna put arthropod parameter in here, the pollinator perameter and, yeah, yeah, I wanted to go back or going back to watershed management. Just really quickly, I wanted to get some more details into, you’ve been publishing recently on web cloud. And so if you could go into a bit of detail on that water, water erosion prediction project and, and how it began and where it’s at now and where you’re adding to it

ERIN BROOKS 42:25
Right, right. Yeah, so. So this WEPP model the Water Erosion Prediction Project, it was a model designed to replace essentially USLE or Russell NRCS planners. If you put a conservation practice in there, they need to document what sort of reduction in sediment, it’s more USLE. And a lot of was actually developed here in Pullman, with Don McCool, historically doing a lot of plot studies, and it’s a good 30 year average erosion rate. And so, but it’s not a process based model that understands dynamics or changes intensity and so it’s not a process based model on WEPP was one of these models is supposed to replace that and it’s the here gets to the politics of you got conservation planners and not really to, you know, teach an old dog new tricks. You know, it hasn’t been adopted completely at all though we’re getting close to that and so it’s a really great model. For me it was understanding, boy, I understand hydrology, landscape hydrology, how then does it feed back into erosion and the Palouse has gone from a time when we used to have a lot of soil crusting, we have a lot of infiltration access or Houghtonian runoff, we’d like to talk about where the precip’s greater the infiltration rate now to a landscape like no till, where erosion now is focused in draws and gullies, we have our gully erosion. And so trying to understand that getting a tool, so WEPP was one of those tools that could do both those types of hydrology, and it was great for a scientist and for me, in Moscow, Bill Elliot, with one of the people actually helped parameterize the wet model back in the 80’s actually I got a position at the Forest Service here in town and said, we can apply WEPP to roads. And so let’s take this model, it does a single hill, we can think of a road like a hill slope, and we got road obliteration. So it’s a big point in time, we’re like, Oh, can we use a model look at erosion before and after? What’s the reduction in sediment load? How that, and so it started with a more of a hillslope laced application. So taking the process based model, put it into a simple decision support tool. And they did a great job of putting WEPP interfaces. So now you got three clicks. This is where I’m located, this is the soil type, this is the steepness of the road. Here’s the field gradient, and essentially takes a process based model and does a very simple prediction, do the 30 year and you could do it return period analysis. This is the 20% route probability of this erosion rate. So this is a start as a hillslope model. Now, Pete Robichaud is now the director there, and was really big into wildfires. And so here post fire response, what’s the risk of this erosion? You know, we know the hydrophobic soils come in. We know that the cover is gone. So the erosion could be massive. And so he took that well, let’s do it as a simple hillslope or, maybe a small catchment? And we’ll do a decision support tool based on the hydrophobicity. Based on the burn severity, what can you expect coming out and so they have all these hillslope tools, they call the FS WEPP interfaces, you could go online, you can find these, I came in from a watershed perspective and say man really is a great need for bigger scale watershed studies. And so, which never before had the model been applied, other than maybe a couple of linking hillslopes and channels a little bit. And so we actually took some of the things we’re learning, they expanded that out into a watershed based model. And for a while, a lot of the GIS growing up and a lot of stuff early on was ArcView, ArcGIS, and all these and, and so some of these WEPP tool, there’s people that actually tied in Chris Renschler has, you know, developed a geo WEPP tool. So actually, well, we can use web in a geospatial like, ArcGIS I got to the point every time ArcGIS updated, you needed, update the code to make WEPP work on it. And so we said, man, what if it’s just an online watershed interface that we developed, and that’s what we had some really great programmers at University of Idaho that I kind of feed ideas, and they do the magic to create these tools. So so now we have this called a WEPP cloud tool. And we did publish that last year to hear that there’s a couple companion papers out in the journal hydrology, really great tool. It looks like Google Maps go in on any point in the landscape, creates a stream network based on the DM extracts all the soils data, then you can break out the hillslopes and channels and take some of the parameterization we have for wildfire, we can upload burn severity maps, and then actually predict sediment load, streamflow, there’s actually a WEPP water quality starting to work with now that’s taking this the SWOT model algorithms and put into water quality. And that kind of gets it more of the stakeholders, they really want to know the watershed outlet and particularly, as we went Florida did a lot of work in Lake Tahoe Lake Tahoe was this place this great icon. Back in the 60s, you can see down into the water 110 feet, it gradually has declined. So now 50, 60 feet. At the same time, Lake Tahoe never been long before. I guess the story goes, Mark Twain was the last one that actually had a major wildfire had a campfire got out of the control back in late 1800s. Nothing had been gone in there. And then all sudden wildfires started showing up. They had a couple of wildfires in Tahoe and they say wow, if we had a lot of sediment coming to our lake, this could really drastically reduce the quality of the lake. And so then this idea of forest thinning came on, okay, she’ll be go in and thin this forest, and then where should we thin it? And our watershed tools were actually really well geared to forest thinning, and and then we can start doing comparisons between forest thinning and the do nothing of leaving it there. And what if there’s a wildfire every 20 years is that better than thinning every 10 to 15 years? And so that was kind of got into this WEPP cloud and applications. And we went for Tahoe now we work with Seattle quite a bit. The Cedar River watershed, where you get all the drinking water from is from an unfiltered water source in Seattle, and they are very concerned about the wildfires scenario. We have NASA is actually giving us funding now to actually use more of their geospatial products to help develop these decision support tools to almost you could almost do a real time early warning system type of tool. And so taking these models and use them as a watershed tool to make informed decisions. So we have now a European version of it. I’m actually going to Spain next week. And we can go in there and actually run watersheds in Spain. We actually, colleagues in Portugal are running, Australia has some major fires, you have an Australian version of the tool now and so it’s yeah, it’s it’s great to see how it’s expanding and the applications of that tool in particular.

BRAD NEWBOLD 49:05
That’s super cool. Yeah, that’s exciting. And to be able to see that, especially going from something like you said, going from you know, ArcGIS, which I used, you know, forever ago and now just being able to have yeah, here a couple clicks, or we’re just gonna go online, couple clicks, and we’re gonna be able to see what we want to see. And so yeah, I think that’s, that’s super fascinating.

ERIN BROOKS 49:25
I know, when I started my masters, I did it on grass. So what’s grass? Now it’s QGIS. Now, but yeah, yeah, that’s least that one’s free. Yeah.

BRAD NEWBOLD 49:36
Well, we’re getting close to the end of our time. Is there are there any other projects you’d like to chat about? Any other things you’d like to share with our audience?

ERIN BROOKS 49:46
Yeah, I guess the one interesting thing ties back to the wildfire and we’ve been working with you guys on as well as kind of looking at the impacts of wildfire on soil water retention and some of the high prop and to look at you know, how does that impact itself? How do we see the Burns effect the carbon? W hich affects the retention properties, the soil texture even changes after wildfire. It’s really crazy. And we’re actually doing trying out with nutrients as well. Phosphorus, how is soaked with phosphorus? And so that’s another kind of a lot of use lab based, or it’s kind of we actually burning soils with propane heaters out in landscape right now and taking samples from a controlled environment. And so yeah, so that’s another angle that we’ve done on trying to understand wildfire. So yeah, a lot of projects, a lot of things.

BRAD NEWBOLD 50:37
And especially, I mean, with those wildfire projects, I mean, it’s super important nowadays, as we’re dealing I mean, this is a whole other thing when you’re talking about modeling climate variability and, and those kinds of impacts. But yeah, definitely being able to see pre and post fire and those kinds of landscape management’s and how we can mitigate some of those risks there. Yeah, it’s super important nowadays. Yeah. All right. Well, I think that’s, that’s all the time today. So thank you for stopping by Aaron. It’s been a great discussion. Yeah.

ERIN BROOKS 51:05
Well, thanks for having me. All right.

BRAD NEWBOLD 51:07
Stay safe, and we’ll see you next time on We Measure the World