A soil geographer’s journey

“The next blog post in our #YourCareerInSoilOrPlantSciences segment comes from Bradley Miller from Iowa State University”

I have always loved maps. When I was a kid, topographic maps were my favourite because I could read the different place names and see how they were located within the physical landscape. This was true for global, regional, and local maps. It was fascinating to me to think about how a place got its name and why it was located where it was. For example, many of the counties in my home state of Iowa are named after historically famous Americans, many of them U.S. presidents such as Washington, Jefferson, Madison, Van Buren, and Polk. However, there were puzzling exceptions. One county is named after a Hungarian, Lajos Kossuth. Well, Iowa just became a state in 1846 and around the time that the state was forming its northern counties, Lajos Kossuth was famous as a freedom fighter. The bust of him in the U.S. Capitol has the inscription “Father of Hungarian Democracy, Hungarian Statesman, Freedom Fighter.” Adjacent to Kossuth County is Humboldt County, which was named in 1851 after Alexander von Humboldt, the world-famous German geographer that was still alive at the time.

Until recently I hadn’t realized that the enjoyment that I received from maps back then is still a large part of why I enjoy my job today. When I look at a soil map, or look at the results of my own digital soil mapping (DSM) work, I am still asking the question of ‘Why is that there?’. I am then scanning around and looking at other sources to understand the context. Is there a spatial pattern? Is there something about the history of the landscape that helps explain its current condition? To me these are fascinating puzzles that are a never-ending source of wonder. Soil geography is like an onion in that pealing back one layer of interactions and complexities reveals another layer to be investigated.

An outdated geology map of Iowa, yet filled with spatial questions. Why are the railroads arranged the way they are? Why do the rivers have the pattern that they do?

Now I should take a step back because I wasn’t consciously making career decisions based on my passion for maps. In high school, I was told that I need to study something that will lead to a good paying job. Because I had a knack for computers the assumption was that I should study computer engineering. After studying computer engineering for a while, I lacked motivation; I felt like I needed to find a purpose beyond making money. I wandered around aimlessly for a while doing odd jobs: pizza delivery, photography for organized college parties, retail in the Mall of America, page for the Minnesota Senate. I still use skill sets from those various jobs, but those are stories for another time. Eventually I found something where I felt I could help solve a problem that really made the world a better place. My favorite recreational activity was canoeing and the newspapers at the time were talking about too much nitrate in the same rivers that I was swimming in. From my canoe, I could see corn fields planted right up to the stream bank. It was a classic setup of a problem appearing to be industry versus the environment, but if we understood the system better, maybe we could figure out a way for everyone to win. After all, nitrate is an important nutrient and nobody wanted to see it lost down the river.

Now having a purpose, I graduated with a B.Sc. degree in Environmental Science and found myself working in a research lab, modeling watersheds. I learned a lot through those experiences. One of those things was the seemingly obvious fact that water flowing in a stream is the product of what is happening in that stream’s watershed. If we want to understand or affect the quantity/quality of the water in streams, we must look to the watersheds. And what are watersheds mostly made of? Soil. Usually when we talk about watersheds and water quality, we talk about the land management practices. Of course, management has a large impact on watersheds and it is the part we have the most control over because management is essentially the human activity component. However, I was struck by how often small watersheds that appeared to be the same in management practices were very different in nitrate concentrations of the water coming from them. There were also examples of fields using the recommended best management practices still having higher concentrations than fields that did not. I was convinced that there was something else different between these areas and the best candidate was the soil, the medium on and through which the water was moving. I tried to use the best soil maps available to find some soil property that could help explain the differences, but it didn’t work. By this time though I realized that there was a lot of room for improvement in the soil maps. Just looking at the soil map delineations over an aerial photograph, one could see variation in the soil that was not portrayed in the soil map. At the same time LiDAR, a technique using lasers to record high resolution elevation data, was becoming available for some areas and that further illustrated ways that the current soil maps could be improved.

An early attempt at public outreach about soil and water conservation.

Realizing that need for better soil maps gave me a new purpose. There are so many people that utilize soil maps for a variety of applications. Since then I’ve worked to become a geographer (you know, the people that spend a lot of time thinking about maps) and to bring together the knowledge of soil science and geography. If I can help provide better soil maps, that information would support activities that improve people’s lives. The value of good soil maps comes in many forms, but some examples include better input variables for models (e.g. weather, hydrology) and the ability to implement site specific management that is better customized to the capabilities of the soil. That kind of informational support first benefits our understanding of how the soil system works and how it interacts with the rest of the environment. The other benefit is that we can then identify where the different processes and interactions are happening, then respond.

The author (in the pit) learning about the soil geography of a landscape different from where he usually works. Luckily he has guides that are both smart and patient.

I entitled this post “a soil geographer’s journey,” but you’ve seen that my story, like that of many soil scientists, is wandering and eclectic. Looking at my past degrees and jobs I could call myself an agronomist, environmental scientist, soil scientist, or a geographer. Frankly, I’ll use whichever description that helps me communicate with respective audiences. The main thing is that I identified a societal need that I can be passionate about. Since then I have been putting my energy into filling that need as best as I can.

Some of the other bloggers for #YourCareerInSoilOrPlantSciences presented some recommended readings, so I’d like to recommend a couple of books that broadened my thinking. A soil science hero of mine is Francis Hole, who was also a geographer. One of my favorite books is one that he co-authored with James Campbell entitled Soil Landscape Analysis. That book is remarkable in its elaboration of the spatial theory that underpins how we map soil and the variety of spatial analyses presented for studying the geographic nature of the soil landscape. To me, Hole and Campbell’s book has a lot in common with Bill Bunge’s book Theoretical Geography, which many consider to be the “seminal text of the spatial-quantitative revolution.” Bunge argued passionately for quantitative spatial analysis and his book likely marks the tipping point for what today is considered geographic information science. The creativity and spatial thinking of those authors is impressive; the main thing that they were missing was the technology we have available to us today. That is why I am so excited to be working in this subject area today. The potential energy is high and the results can help people to understand, utilize, and conserve one of our most fundamental natural resources.

Author: Bradley Miller

Twitter: @geograph_miller

Bradley Miller is an assistant professor in the Agronomy Department at Iowa State University. He is also a fellow with the Institute of Soil Landscape Research at the Leibniz Centre for Agricultural Landscape Research (ZALF). His research is broadly described as soil informatics, which includes the science of spatial prediction and communication of soil information.

Recommended reading:

Hole, F.D., Campbell, J.B., 1985. Soil Landscape Analysis. Rowman & Allanheld, Totowa, New Jersey.

Bunge, W. 1962. Theoretical Geography, 1st ed. Gleerup, Lund.