Old-growth forests in Europe account for less than one percent of all forested areas worldwide. However, they are still very important in terms of ecological value. They represent small vestiges of how Europe’s past primeval forests may have looked.
In addition to the aesthetics and historical significance of these old-growth forests, they are also very function. For example, the provide various ecosystem services such as:
- Biodiversity maintenance,
- Long-term carbon storage,
- And landscape uniqueness.
As a result, old-growth forests are natural laboratories of significant value. They show us how trees with different dimensions and of different ages respond to global change drivers including climate warming and land-use changes.
Even though there is increasing attention being placed on these important ecosystems, knowledge of the long-term effects of climate change in the Mediterranean is largely limited. A recent study by Spanish and Italian scholars from multiple universities discovered that forests in the mountainous regions of the Mediterranean showed remarkable resistance to climate warming.
The Pollino National Park – Studying the Climate Change Impact in an Ideal Setting
Pollino National Park is the largest protected area in Italy. Researchers studied two conifer species and two hardwood species in that location. They were sampled along with an altitudinal gradient which ranged from a drought-limited low-elevation hardwood forest to a cold-limited subalpine pine forest. Using dendrochronological methods, the scientists characterized radial growth dynamics of old versus young age trees.
Each of the sites which appeared in the study were chosen for their biological and ecological value. They represent exceptional example of intact and ancient European forests due to the presence of large trees, standing dead trees, abundant woody debris left on the ground and a high structural heterogeneity. Aldo Schettino from Pollino’s National Park states, “Notably some of the oldest dated trees in Europe have been found in the Pollino massif.” They are restricted to mountain sites, which are characterized by irregular topographic conditions like steep slopes and shallow soils. These factors allowed the trees to “be nearly untouched for centuries” with “very few cases of traditional livestock and silvicultural activities” having not been abandoned over the past century. This contributes to their transition to increasingly natural conditions.
Mediterranean Old Growth Forests – A Treasure Chest of Biodiversity and Resistance to Climate Change
The results of the study constitute a relevant finding in contrast to what is happening in the Mediterranean environment where various forest ecosystems are threatened by climactic extreme events which show clear signs of growth decline and dieback phenomena that have negative consequences in terms of carbon sequestration, biodiversity and ecosystem services. Some differences have been found depending on the tree taxa and local climactic conditions. Some trees showed marked growth enhancements in response to warming at cold sites while trees of low-elevation hardwood forests showed stable-growth behavior highlighting the ability of specific species to acclimate to the warming trends found in Mediterranean mountain ranges.
Relevant Implications for Biodiversity and Forest Naturalness Conservation
Researchers were excited to discover a fast-growth trend in young individual trees in comparison to their older counterparts. By studying and monitoring the growth performance of young trees in association with old trees, the researchers can track old-growth functioning in the face of global change. The conservation of mountain ecosystems represents an important target of Agenda 2030. The findings could have relevant implications in carbon cycle mitigation and in biodiversity conservation that support programs for restoration of forest ‘naturalness.’
Like researchers, we are encouraged by these results. We hope you are too. We look forward to bringing you the latest news you can use related to trees and the environment world-wide. Thank you for reading our blog.
