When you hear the words “renewable energy,” do you think about solar power? Wind turbines? Hydrogen?
What about grass? Shrubs? Trees?
There’s a new (but also ancient) clean energy game in town that uses plants as a fuel source.
Three very different studies by three masters students at West Virginia University’s Davis College illustrate the vast range of possibilities for “biomass,” or crops grown for energy production and used to produce a multitude of goods: chemicals, fertilizer, child-safe adhesives.
Forestry student William Smith, of Bay Village, Ohio, uses drone technology to focus on the original biomass, wood. His work allows logging companies and forestry management agencies to evaluate best practices for calculating the removal of bioresidues left by forestry activities and for minimizing soil erosion when constructing features like logging roads or landings.
Andrew MacKenzie, a wildlife and fisheries resources student from Springboro, Ohio, also looks at trees, but he’s concerned with growing them. Mackenzie is restoring wetlands through tree planting, using a processed form of biomass called biochar to fertilize the soil and accelerate the growth of native tree species.
From Baltimore, Maryland, forest resource management student Mica Keck fertilizes with biochar, too, though her research happens on lands like former mining sites with no agricultural value. She investigates whether enriching soil with biochar creates fewer greenhouse gases than conventional nitrogen fertilizer, and whether biomass crops like switchgrass can be grown in that soil, potentially restoring its capacity for food production.
For me, biomass is about soil reclamation and a potential energy source. The first thing that comes to mind when I think of biomass is the renewable energy potential, because biomass is a completely organic way of both providing an alternative for fossil fuels and reclaiming land that’s already been degraded.
When we talk about biomass, typically we’re talking about crops called “feedstocks” that are grown specifically for bioenergy potential. A lot of biomass crops are herbaceous grasses with a high content of lignin and cellulose. That starch and carbon is easily converted into energy potential.
Additionally, they can be grown on anything. They don’t need good soil. They’re perennial. They’re renewable. They come back every year and can be harvested several times throughout the year, and that comes along with these deep root systems and the way they continue to build up the soil as well.
My research looks at using marginal lands and reclaimed mines for bioenergy crops. I’m trying to figure out the carbon neutrality potential of biochar as a fertilizer amendment by measuring how biochar influences greenhouse gas exchanges in the soil.
How much nitrous oxide do soil microbes emit? How much carbon is sequestered in that biochar, and does it increase total soil carbon?
My interest is in biochar’s ability to be a carbon-neutral energy source while enhancing those properties of the soil, and to figure some of that out, I play with a whole lot of dirt.
I’m working in a wetland restoration context to see if we can increase the biomass of trees – increase tree height, tree width and survivorship – by fertilizing the soil with a 10% biochar, 90% compost mix. Replanting trees helps with flood pulsing levels in wetlands, since more water retention reduces flooding.
I’m asking, “Can biochar enhance tree growth?” and at my sites, so far it has, although we’re talking a difference of millimeters.
We’ve planted about 2,500 trees that we have to take measurements for. What that looks like is heading out to the sites with a meter stick and calipers, and every four to five steps, I’ll bend down, measure the width of the tree at ground level, measure the height from where the tree comes out of the ground to its tallest stem, then go to the next one. There’s a lot of bending.
Biochar is made through pyrolysis: heating the biomass without oxygen. That heating process can happen slowly or fast. My research suggests that slow-pyrolysis biochar is better suited as a tree fertilizer than fast-pyrolysis biochar because the nutrient retention is a little different, the water capacity’s different, whereas fast pyrolysis inhibits or prevents tree growth because too many nutrients are retained.
With slow pyrolysis, the biochar nutrients can get to that tree root system and there are more nutrients in the soil. Slow-pyrolysis biochar gives more to the trees and keeps more in the soil – that’s the double benefit.
My work in biomass focuses on forestry practices, so I think a lot about untapped potential. Biomass is there in the woods, waiting to be used. There’s a lot of potential for replacing current fossil fuels with biomass. It’s there, waiting for a good way to utilize it.
I use drones to look at best practices for logging sites – skid roads, haul roads, landings. I’m trying to answer the question, “Is there a better way to check best management practices for forestry? How might that process or those practices be improved?”
With that, I’m looking specifically at a clearcut harvest, where you’re taking off all those trees, as well as harvests that also take the residue off the site. I want to know whether there should be additional best management practices or separate guidelines for residue removal, and I expect it will largely depend on a site’s history, its existing soil nutrients.
My main objective is to control water movement via the slope or length of logging roads, or via features like streamside management areas – basically a buffer on a stream. We also use water bars, where for any continuous segment of exposed soil on the roads, a water bar diverts the water off to avoid increasing the sedimentation being carried away.
Another part of my work is time motion studies looking at the harvesting aspect of logging and shipping. Those can be used for justifying different methods of harvesting, helping to get these different products out to end users.
CONTACT: Leah Smith
Davis College of Agriculture, Natural Resources and Design