Text and photograph by Estrella Conde Raposo
Last Saturday, March 21st, was International Day of Forests, and in this post we want to pay tribute to forests by presenting the results of a scientific article recently published by researchers from the Global Change Research Institute (IICG URJC). We hope you enjoy it:
In the Iberian Peninsula, where forest restoration has been a constant over the last century, a crucial question arises: do plantations allow for the recovery of biodiversity levels found in mature forests? Research from the IICG-URJC explores this question in Mediterranean environments from the perspective of a key group of organisms: ants. According to the results, generalist species abound in plantations, while mature forests are concentrated with species associated with forest environments.
The study, published in Forest Ecology and Management, analyzes 45 forests in Madrid and Castilla-La Mancha, including plantations of varying ages, some over a hundred years old, and well-preserved mature forests. Researchers examined the composition and diversity of ant communities, considered bioindicators due to their sensitivity to structural changes in the habitat and their role in ecosystem functioning. This study reveals that while plantations allow for the recovery of species numbers, they do not evolve toward the typical community of mature forests, even a century after their establishment. “It’s not just about how many species there are, but what species they are and what role they play in the ecosystem,” explains the article’s first author, Estrella Conde Raposo, a researcher at the IICG-URJC.
Beyond comparing forest types, the study confirms that forest structure is a determining factor. Average tree height and variation in tree diameter influence the presence of forest species. These attributes are more frequent in mature forests, which explains their capacity to support more diverse and functionally rich communities. The global loss of mature forests since the end of the last century makes the study’s results even more relevant, demonstrating that these ecosystems are not easily replaceable. Protecting those that still remain and, at the same time, guiding plantation management towards more diverse structures is key for these pine forests to eventually provide refuge for the forest species that characterize the ant communities of well-preserved forests.
This work is part of the BioForest project, led by the IICG-URJC and supported by the Biodiversity Foundation of the MITECO, within the Recovery, Transformation and Resilience Plan (PRTR) funded by the European Union – NextGenerationEU. One of the project’s objectives is to identify which structural and ecological features should be promoted to make forest restoration more effective. Furthermore, it also highlights the importance of incorporating floristic and faunistic indicators into the evaluation of restoration success, as these reveal key ecological aspects.
Reference:
Conde-Raposo, E., Azcárate, F.M., López-Angulo, J., Jiménez-López, F.J., Pescador, D.S., Calvo-Donate, V., Rojo-Valencia, M., Navas-Golmar, N., Escudero, A., García-Cervigón, A.I. (2026). The value of old pine plantations in ants’ conservation in the Mediterranean: a comparison with well-conserved forests. Forest Ecology and Management, 606, 123556. https://doi.org/10.1016/j.foreco.2026.123556