European forests need to solve two crises
Photo Credit: Pierre Jeanneret
Scientific Frontline: Extended "At a Glance" Summary: European Forest Carbon and Biodiversity Management
The Core Concept: European forests are frequently managed as carbon sinks, utilizing dense, homogeneous plantations of rapidly growing trees to absorb carbon dioxide. However, this one-sided focus on carbon sequestration fails to address the ongoing biodiversity crisis, as optimal carbon capture often conflicts with the diverse habitats required to support varied ecosystems.
Key Distinction/Mechanism: While uniform plantations of young trees efficiently absorb carbon for timber production, ecological biodiversity depends on structural variation. High biodiversity requires a mix of living and dead trees, variable tree sizes, and undisturbed decay, whereas carbon-focused management typically involves harvesting trees before they naturally die and fall.
Origin/History: Over the past thirty years, European forest areas have increased, yet 80 percent of assessed forests maintain an "unfavorable" conservation status. To address this disparity, researchers published a comprehensive study of 99 European forest sites in Nature Communications to evaluate the relationship between carbon policies and ecological health.
Major Frameworks/Components:
- The Triad Approach: A proposed management framework dividing forests into three distinct zones: intensive production areas optimized for timber and carbon storage, untouched areas managed exclusively to maximize biodiversity, and experimental laboratories for testing close-to-nature management compromises.
- Carbon Storage Categorization: The assessment divides forest carbon into three biological structures to evaluate ecological responses: living trees (above-ground biomass), standing dead wood (upright dead trees), and lying dead wood (fallen logs).
- Biodiversity Indicators: The research analyzed the relationship between carbon structures and more than 3,500 species across groups including vascular plants, mosses, lichens, fungi, beetles, and birds.
Branches of Science: Forest Ecology, Conservation Biology, Silviculture, Botany, Zoology.
Future Application: Land managers and policymakers can implement the triad framework to strategically designate land use, maintaining low-biodiversity regions as highly efficient carbon sinks while strictly protecting older, unmanaged forests to cultivate specialized habitats for vulnerable fungi, insects, and animals.
Why It Matters: The research demonstrates that relying on a single forest to simultaneously solve both climate change and biodiversity loss is largely ineffective. Establishing specialized management zones ensures that Europe can meet its carbon emission reduction targets without sacrificing the ecological integrity of its native environments.
Forest areas can act both as carbon sinks and as vital habitats for thousands of species—but not necessarily at the same time. This has important implications for how Europe should manage its forests, says a University of Copenhagen researcher.
Trees act as a primary mechanism for reducing atmospheric \(\mathrm{CO}_2\) emissions and the resulting climate change. As trees grow, they absorb carbon dioxide from the atmosphere and store it as carbon in their trunks, branches, leaves, and fruits. This process is most efficient early in a tree’s life, when growth is fastest.
Across Europe, large forest areas are being planted and managed with this purpose in mind. Trees of the same species are often planted in neat rows under plantation-like conditions, where they efficiently absorb \(\mathrm{CO}_2\). Once they have passed their fastest growth phase—when they are also best at storing carbon—the trees are typically felled, making room for new trees that can grow and store even more \(\mathrm{CO}_2\).
This is a very effective way of managing forests that both store carbon and produce timber for industry. But there is one major problem, says Associate Professor Sebastian Kepfer-Rojas from the University of Copenhagen. It only addresses one of the world’s two major environmental crises.
“We are facing two environmental crises. One is the climate crisis, and the other is the biodiversity crisis,” he says.
The problem with the types of forests described above is that, while they may be excellent carbon sinks, they do very little to support biodiversity. A one-sided focus on carbon storage can lead to uniform forests with few species.
“The forest area in Europe has increased over the past 30 years, but that does not automatically mean that the ecological condition of forests has improved. Around 80 percent of the assessed European forests have a conservation status classified as ‘unfavorable,’” says Sebastian Kepfer-Rojas.
The Ecological Function of Decaying Biomass
According to Sebastian Kepfer-Rojas, the core problem with many European forests is that they are too homogeneous, too densely planted, and managed so that trees are planted and harvested at the same time—before they have a chance to die and fall naturally.
“High biodiversity requires variation across many different parameters: trees of different sizes, and a mix of living and dead trees,” he explains.
In Denmark, it has been decided that large parts of state-owned forests are to be left unmanaged. The Green Tripartite Agreement (Den Grønne Trepart) also proposes converting significant areas of current farmland into untouched forest reserves. This means that trees are not systematically harvested, but instead allowed to die and fall, creating habitats for a wide range of species—including fungi, insects, and bats. In some places, trees are even deliberately damaged to speed up the formation of habitats for specific species.
“Even though Denmark does not have a large forest area, what we do here matters a great deal for biodiversity. I would actually say that Denmark is quite far ahead in this area. The issue has been taken seriously, and that sends a strong signal, but we are still a long way from where we need to be,” says Sebastian Kepfer-Rojas.
Balancing Carbon Sequestration and Biodiversity
Is it possible to manage a single forest area so that it both functions optimally as a carbon sink and supports high biodiversity?
This is a key question being discussed by Sebastian Kepfer-Rojas and his colleagues. Together with researchers from across Europe, he coauthored the scientific article “European Forest Carbon and Biodiversity Policies Have a Limited Win-Win Potential.”
In the study, the researchers examined a large number of European forests and analyzed the relationship between carbon storage and biodiversity. The aim was to find out whether it is possible to strike a golden balance—a true win-win—in forest management. In other words: can one forest be managed to optimize both carbon storage and biodiversity, or does this require different types of forests with different purposes?
As the title of the scientific article suggests, the researchers conclude that there are only limited opportunities to combine optimal carbon storage with high biodiversity in the same forest. While there was generally a positive relationship between biodiversity and carbon stored in deadwood, there was no clear link between high biodiversity and the amount of carbon stored in living trees.
Sebastian Kepfer-Rojas and his colleagues therefore propose a triad approach to forest management, in which forests are managed in three different ways:
- Some forest areas should be optimized for timber production, while still ensuring a high and stable carbon store.
- Some forest areas should be managed primarily to maximize biodiversity.
- Some forest areas can function as test laboratories, where researchers continue to explore the potential for more balanced management approaches.
“You could call it a diplomatic solution. But I think it is just as important to discuss where we do what. In some old forests, it makes sense to keep our hands completely off. In other areas, where the biodiversity potential is already low, intensive production forests may be appropriate. And then there are areas where close-to-nature forest management can be a good compromise,” says Sebastian Kepfer-Rojas.
Published in journal: Nature Communications
Title: European forest carbon and biodiversity policies have a limited win-win potential
Authors: Lorenzo Balducci, Elena Haeler, Yoan Paillet, Edoardo Alterio, Christian Ammer, Frédéric Archaux, Steffen Boch, Christophe Bouget, Gediminas Brazaitis, Francesco Chianucci, Andrea Cutini, Pallieter De Smedt, Inken Doerfler, Daniel Dvořák, Markus Fischer, Paolo Giordani, Marion Gosselin, Jacob Heilmann-Clausen, Eva Holá, Jeňýk Hofmeister, Jan Hošek, Itziar García-Mijangos, Philippe Janssen, Kirsten Jung, Sebastian Kepfer-Rojas, Nathalie Korboulewsky, Daniel Kozák, Tomáš Kuras, Thibault Lachat, Jiří Malíček, Anders Mårell, Martin Mikoláš, Jörg Müller, Francesca Napoleone, Björn Nordén, Péter Ódor, Zdeněk Palice, Peter Schall, Tommaso Sitzia, Kastytis Šimkevičius, Miroslav Svoboda, Aleš Tenčík, Flóra Tinya, Giovanni Trentanovi, Mariana Ujhazyova, Kris Vandekerkhove, Michael Wohlwend, Wolfgang W. Weisser, and Sabina Burrascano
Source/Credit: University of Copenhagen
Edited by: Scientific Frontline
Reference Number: eco110726_01