Forests are home to most of the Earth’s terrestrial biodiversity (FAO, 2022) and much of the biodiversity in Europe (Muys et al., 2022). Ranging from lush deciduous temperate forests to snow-covered boreal forests and Mediterranean scrublands, Europe’s forests represent a rich variety of unique natural heritage. This diversity of ecosystems provides homes for countless plants, animals, fungi and microorganisms, playing a crucial role in maintaining ecological balance and supporting the welfare of societies and economies.

Preserving biodiversity is critical, as around 1 million animal and plant species worldwide are threatened with extinction (IPBES, 2019) due to habitat loss, pollution, overexploitation, invasive alien species and climate change (Brook et al., 2008). In Europe, primary and old-growth forests and the biological diversity they harbor are of particular conservation importance since many disappear before they are identified and mapped (Mikolas et al., 2023). Climate change and frequent extreme climatic events such as wildfires threaten managed forests, which offer important habitats to insects, birds, and mammals.

Forests and the contribution they make to broader biodiversity conservation goals have become the focus of EU and global policies (Lier et al., 2022) and research discussions. The Kunming-Montreal Global Biodiversity Framework, 2020 Aichi Biodiversity Target 5, Sustainable Development Goal 15, the Bonn Challenge, the European Union Biodiversity Strategy for 2030, and the New European Union Forest Strategy for 2030 recognize the role of protecting and conserving forests and sustainably managing them to safeguard biodiversity. Action is needed to reduce biodiversity loss, but ultimately, why do we need to preserve biodiversity?

Fire salamander (Salamandra salamandra) on a tree. (Ars Ulrikusch/Adobe Stock)

From genes to ecosystems, from ecology to natural capital

Species extinctions do not only undermine different forms of life on the planet but have consequences for human well-being and economic activities. Clean air, water, carbon sequestration, medicine, climate regulation, natural disaster prevention, materials such as wood, cork, and resins, as well as food supply (e.g., mushrooms, berries, etc.) are some of the many services provided by forests and their biodiversity.

Biodiversity has differently sized building blocks, from the microscopic level of genes to variations between species and large-scale ecosystems that shape entire landscapes. Genetic diversity is often overlooked but is critical also in managed forests as it helps to withstand, adapt, and recover from changing environmental conditions (Fady et al., 2015).

Due to climatic changes, native and invasive pests and diseases are expanding their ranges, threatening the health and future of forests. Biodiversity helps to cope with these changes in ecological conditions and increases the resilience of the forests to disturbances. For example, a genetically diverse forest had a bigger probability of possessing trees capable of resisting disturbances such as pests, droughts, wildfires, invasive species, and diseases (Kelblerová et al., 2022)

Forests provide 3.6 million green jobs in forestry and wood-based sectors in Europe. Global demand for forest products continues to rise, and there is a need to manage forests for greater productivity, with closer attention to the services they provide (Balla et al., 2021). The presence of a diversity of species in forests is also important in this regard, such as mycorrhizal fungi that help boost the productivity of trees used for wood production (Muys et al., 2022).

Besides wood production, a study found that half of the forests in the EU offer multiple forest ecosystem services (Orsi et al., 2020). According to Forest Europe (2020), in 2015, the reported market value for ecosystem services in 14 countries of Europe was around 495 million euros. For example, in mountain areas, wood production, water supply, erosion control, climate regulation, and recreation are valuable forest ecosystem services. The regulating services of soil formation, which in this study was considered as soil organic carbon, are evidently highlighted in the Northern European forests. In addition, pollination is a service underlined in the French and southern European forests, being positively related to erosion control since pollination is almost exclusively supported by forest edges close to crop fields.

Although forests are typically not associated with bees and other pollinators, forests play a vital role for many pollinator species, which rely on specific habitats such as deadwood and other nesting sites exclusively available within forested areas. In turn, more than 70% of global food crops depend on animal pollination (IPBES 2019). A study estimated that honeybees, bumblebees, wild bees, and other pollinators contribute at least 5 billion euros annually to the European agriculture industry (Vysna et al., 2021). Since food production and consumption are major drivers of biodiversity loss, it is necessary to change the way we produce food (Benton et al., 2021) in order to better protect forests.

(InputUX/Adobe Stock)

Forest management and biodiversity

Biodiversity has always been essential for maintaining health and sustainable forest management planning. However, due to uncertain future conditions, biodiversity has been highlighted (Cosovic et al., 2020) as an “insurance” to ecosystem functioning (Baumgärtner, 2007). Different types of forest management practices influence forest structure and biodiversity, favoring some species over others.

A study found that canopy gaps and structural attributes related to old-growth forests (e.g., stand age, share of large old trees) were positively correlated with species richness (Zeller et al., 2023). Therefore, it is important to consider deadwood, wood debris, old trees, diverse stand structures and forest gaps for conserving biodiversity. This can directly support forest management activities; for example, lying and standing deadwood improves the nutrient balance in soils and preserves water (Mauser, 2021). Another example is that stands with diverse structures are less sensitive to resource competition when compared to even-aged monocultures, which could lead to a gain in productivity and resilience to abiotic and biotic stress (Ammer, 2019). This type of knowledge could be shared with policymakers, forest owners and managers, and other stakeholders when preparing new regulations and harvest planning.

The need for biodiversity guidelines for Sustainable Forest Management tailored to forest and conservation practitioners in Europe has been suggested in scientific literature (Oettel & Lapin, 2021). Understanding the role of biodiversity helps practitioners (Gustafsson et al., 2020) and forest managers to implement forest management practices for biodiversity conservation (Díaz et al., 2009), such as retention forestry (Lindenmayer et al., 2012), mixed forests or continuous forest cover, as well as ecologists in future research (Duflot et al., 2022). The European Commission has recently released Guidelines on Biodiversity-Friendly Afforestation, Reforestation and Tree Planting, and in Closer-to-Nature Forest Management, with the goal of providing a set of practical recommendations to support a better implementation of biodiversity-oriented forest practices.

Sustainable forest management considers ecological, social, and economic values of forests. It focuses on timber resources while guaranteeing biodiversity and conserving carbon stock. When well-planned, sustainable forest management practices, forest restoration and biodiversity-friendly afforestation complement each other to promote resilience and biodiversity conservation (Santopuoli et al., 2021).

Forest restoration and local engagement 

Forest restoration is a crucial tool to help reverse widespread forest degradation and fragmentation, diversify even-aged tree monocultures and enrich homogenous landscapes that lack forests and woodlands. Biodiversity-based restoration measures are essential for climate adaptation, as they can create climate refuges for displaced species, improve species’ capacity to migrate across the landscape and stimulate their natural adaptive capacity through behavioral and evolutionary responses (Gross et al. 2017).

Pine tree planting for reforestation. (Robert Kneschke / Shutterstock)

Current examples of how forest restoration and afforestation can be used to meet multiple land-use demands and foster biodiversity are provided by the EU-funded project SUPERB, which is showcasing restoration practices in 12 European countries. For instance, in Sweden, SUPERB is enhancing forest connectivity on a landscape scale to improve conditions for biodiversity and indigenous Sami community reindeer husbandry, a vital activity for local communities. In Denmark, it is involving local students in the process of “veteranizing” young trees – that is, recreating characteristics of older forests that can support biodiversity, such as the presence of deadwood fragments. And in Germany, it is reforesting spruce stands affected by bark beetle outbreaks with climate-resilient species that are more likely to support continuity of ecosystem services and wood provision for future generations. Measures like this that foster local engagement and enhance local livelihoods can increase support for the maintenance of restoration’s ecological outcomes for biodiversity. Social acceptance is a decisive factor in enabling the adoption of restoration measures (Gann et al., 2019; Toledo et al., 2013), particularly at a large scale.

Although different from each other, forest protection, sustainable forest management and forest restoration all have a role in safeguarding and nurturing Europe’s biodiversity heritage. As society strives for a balance between ecological, social and economic values, the contribution of each organization, business and individual is paramount. Although biodiversity is threatened, actions both small and large can positively contribute to the tapestry of biodiversity protection.