UVM research reveals how old, dead trees in ADK streams are a natural climate solution
If you’ve ever gone hiking in the Adirondack wilderness, you may have seen old, dead trees that have fallen into streams and are decomposing. That wood has captured and is storing carbon. Researchers from the University of Vermont studied the carbon storage capacity of dead wood in streams in the Adirondacks and New Hampshire and how it can serve as a natural climate solution.
PhD candidate and Gund gradute fellow Stephen Peters-Collaer worked with UVM Forestry professor and Gund fellow William Keaton on the paper, which was published in March. Their research was funded by a federal grant from the US Dept. of Agriculture.
Emily RussellUVM research reveals how old, dead trees in ADK streams are a natural climate solution
PhD candidate Stephen Peters-Collaer worked with UVM Forestry professor and William Keaton on the research. Photo provided by UVM
STEPHEN PETERS-COLLAER: The specific interest in the carbon storage of wood in streams came about in part because in the Eastern US, there’s really limited, if any, information on the amount of carbon stored in dead wood in streams. We have great data on the amount of carbon stored in dead wood on the forest floor, but no one had looked at that in the streams on the East Coast. So we wanted to get the first understanding of how much carbon was stored here, as well as how that changes as forests age. That’s part of the reason we used two sites— the Hubbard Brook Experimental Forest, a middle-aged forest in New Hampshire, and then much older forests in the Adirondacks. So we can look at how age and characteristics of the forests impacted the amount of carbon stored in deadwood in those streams.
EMILY RUSSELL: Is there a simple way to explain how you determine and measure carbon storage in those two places?
PETERS-COLLAER: Probably the simplest way is that we had great field crews from the University of Vermont. We spent several summers walking up and down these streams, basically measuring all of the wood in the streams. We’d be climbing over big log jams and ducking underneath to measure length and diameter and all these sorts of things. And then we brought that back into the lab and there are some well-researched calculations on how to convert the measurements we took into carbon numbers.
The field crew from UVM collecting data in an old-growth forest in the Adirondacks at Clear Lake Outlet. Photo provided by UVM
RUSSELL: Why was it important to compare the carbon storage in wood in old-growth forests [in the Adirondacks] to mature growth forests in New Hampshire? And what did you find in terms of the difference between carbon storage in those two places?
WILLIAM KEETON: These days, there’s huge interest in the role that forests can play as a natural climate solution, helping us fight climate change by sequestering carbon and storing it in biomass. But a missing piece of our understanding of how that works is the carbon storage value that streams might provide and that wood in streams might provide.
Now, we know that wood levels reach their highest in these old-growth streams in places like the Adirondacks, but the question is, how much wood do these younger forests have and are they on their way towards redeveloping similar levels of wood and carbon storage as we might see in an old-growth forest?
The majority of our forests in the Northeast are young or middle-aged and are only about halfway along this pathway of recovery. So it stands to reason that as they continue to age and as large woody debris accumulates in the streams, that carbon sink or that bank of stored carbon will continue to accumulate. Steven’s work and our work estimates that those old forests store something like four to five times as much or more than mature forests, which suggests that there’s a lot more sink capacity for carbon storage in our streams.
RUSSELL: How can this study be used outside the scientific community? Why does this research matter?
PETERS-COLLAER: There are a few ways that this is important to non-scientific folks. For people actively working in land management, there are many folks, either land owners or land managers, who are interested in using their land as a natural climate solution to help take carbon out of the atmosphere and store it on the landscape.
Previously, when people were thinking about this, they hadn’t considered streams or freshwater systems in general. So I think this hopefully starts a conversation where land owners and land managers can begin to incorporate these values- the amount of carbon stored in wood in streams and potentially later on maybe other freshwater systems- in their use as a natural climate solution.
And I think there’s also some value in thinking about ‘strategic wood additions.’ So there’s a lot of work across the Northeast that looks to actively add wood to streams because, as we’ve discussed, the streams have much less wood in them than they used to when we had older forests. This research shows another benefit to that type of land management work- the strategic wood additions that are already being used for fish habitat, flood control, and a variety of other aspects.
Stephen with crew and woody debris in stream in a mature forest in Hubbard Brook Experimental Forest. Photo provided by UVM
RUSSELL: After doing this research and spending so much time out there in the Adirondacks and in the White Mountains, did it make you see the world differently or think differently about natural climate solutions?
PETERS-COLLAER: Well, I can jump in first since Dr. Keeton’s been working on this for two decades, so it might have had more change in my perspective. I think one of the things that it really highlights for me is the interconnectedness of nature. Often, people tend to think about forests or streams or lakes rather than thinking about how these systems impact each other. And in our work, we saw that the land clearing of forests has really had a profound impact on streams. And so we’re trying to understand how everything works together.
I also think there’s some value to appreciating the messiness of these systems and knowing that a stream that has a lot of wood in it and wood that’s crisscrossed and forming these log jams is actually really healthy and really good for a system rather than just viewing it as a mess in an otherwise neat landscape.
KEETON: Those are great answers. I’ll just add that I’ve always been a big tree lover. I love big trees and I think this study brought to light yet another value that large trees provide. We know that they are important for habitat and lots of other things. We didn’t know that when they fall into streams and accumulate there over decades, they store a lot of carbon that would otherwise be in the atmosphere as a greenhouse gas. So it’s yet another reason to love big trees, especially if they’re growing alongside a beautiful stream. What could be better?