Digging into the Climate-Preserving Power of Soils
Guillermo Hernandez Ramirez explains why he focuses on understanding the ground beneath our feet.
By Olivia DeBourcier
Soils are the basis for all terrestrial systems. They purify water, grow our food, and are always there to keep us grounded (pun intended). But despite their importance, soils don’t often get the attention they deserve. Guillermo Hernandez Ramirez is here to change that.
As a soil scientist at the University of Alberta, he’s studied soils all around the world and leads the Sustainable Land Ecosystems Research Group. We sat down with Hernandez Ramirez to get the dirt on why soils are such an essential part of a sustainable future.
Why should we care about soil?
Soils can store carbon. So that means that if we are able to increase carbon from organic matter in the soil, then we are actually removing that carbon from the atmosphere. This can help us to mitigate climate change, at least for several decades. And this can help us to gain some time to find potential solutions to climate change.
And of course, there are also other greenhouse gases like methane and nitrous oxide. Those two can also be emitted from soils, but in some cases, soils can also consume them. By having specific management, we can actually enhance that sink of methane, and in the case of nitrous oxide, we are able to reduce half or even 80 percent of those high emissions.
So soil management can actually mitigate climate change!
Soils can also help with adaptation to climate change. By increasing organic matter you can improve water availability in soils, then we can also have better availability of water for plants. And that can help us better handle droughts or other conditions that are challenging for growing plants.
There are other aspects that we also need to think about too. Not all ecosystems are just about producing food. There are cultural values that we need to acknowledge. Like recreational values and the aesthetic of the landscape. And there is wildlife conservation, and water regulation, there are so many different values that need to be accounted for.
Soils have a memory. If we have managed that resource in a beneficial way, then we can see those benefits. But, if we manage detrimentally, we can also see that.
What do you mean by saying the “soil has memory”?
If we have added some materials to the soil, those will continue to cycle inside the soil. Over time, they will be transformed. But until that happens, we keep remembering that fingerprint, that identity that was created by how we manage it.
For example, changes in how microorganisms live and how they interact with each other can last for 20 years. Some of our soils still remember when, in this part of the world, we had grasslands and buffalo going across. You can see some of the evidence for what was happening here because there was fire in those grasslands and there was grazing and you can still see some of that evidence of how it was over thousands of years.
How long does it take to do some of this research?
We have experiments that have been in place for several decades, even for 80 years or for 100 years. This is a generational relay of different resources and different scientists who have been keeping these experiments in place so that the new generations can continue to learn about how it responds in the long run.
Your lab looks at soils from a variety of landscapes all around the world. Given that soil types can change dramatically within even the same forest, how do you deal with the variety of these settings in your research?
That heterogeneity keeps us busy, but it also keeps us very entertained in the sense that there is always something new for us.
In the past, [our discipline] had this segmentation of landscapes instead of trying to integrate and bring it all together. For our lab, we try to study pretty much all terrestrial ecosystems. So we go all the way from croplands and grasslands to forests and even to the mountains. That way, we can build more of that general understanding of how these processes and ecological relationships actually work.
There is no way to improve one of those ecosystems without having an impact on neighbouring or even faraway ecosystems.
What kinds of management practices are being used or maybe are starting to be used in order to be more sustainable in our management of soils?
We talk a lot about choices of crop rotation. By including more diversity of crops or grasses in grasslands or even a different tree species in the forest, then we can actually develop better resiliency.
Additionally, by having not just annual crops but also some perennial crops we can see multiple benefits. In the early spring, we have plenty of water, but with most annual crops the space is empty. By doing perennial crops and having plants growing all the time, we can access those spring resources.
The other thing that we would like to see is recycling materials and resources. Our whole society is very efficient at bringing food from rural landscapes to the cities. When we use it, some of that becomes biosolids. There is a large abundance of biosolids, some of that can be composted. We take several different kinds of biosolids and then we bring it back to places where we have grasslands or where we have croplands and then we use it for growing these plants. Sometimes this is perceived as “Oh, you’re just using that resource”. But even more than that, we’re just trying to recycle it back where it came from.
What is something you want your students to remember about soils?
Soil is there all the time and it’s able to support life. It’s a central piece of our ecosystems and we are managing those resources and being a steward of the resources.
The way that we manage soils can have a strong impact on how we end up having different food security around the world, or how we can handle climate change or environmental conservation in general.
Anyone can contribute to healthy soils!
Follow Guillermo Hernandez Ramirez’ tips to help build healthier soils.
- “Purchase and eat fruits and vegetables that are locally in season.” You will enjoy a greater diversity of foods, which is also good for your health.
- “Find a plot in a community garden.” This builds communities around producing food, generating stakeholders who care about soil health.
- “Separate organics from waste.” Composting at home can create a valuable resource for your own garden soil, while municipal composting benefits the wider community.