An assessment of the state of conservation planning in Europe

Expanding and managing current habitat and species protection measures is at the heart of the European biodiversity strategy. A structured approach is needed to gain insights into such issues is systematic conservation planning, which uses techniques from decision theory to identify places and actions that contribute most effectively to policy objectives given a set of constraints. Yet culturally and historically determined European landscapes make the implementation of any conservation plans challenging, requiring an analysis of synergies and trade-offs before implementation. In this work, we review the scientific literature for evidence of previous conservation planning approaches, highlighting recent advances and success stories. We find that the conceptual characteristics of European conservation planning studies likely reduced their potential in contributing to better-informed decisions. We outline pathways towards improving the uptake of decision theory and multi-criteria conservation planning at various scales, particularly highlighting the need for (a) open data and intuitive tools, (b) the integration of biodiversity-focused conservation planning with multiple objectives, (c) accounting of dynamic ecological processes and functions, and (d) better facilitation of entry-points and co-design practices of conservation planning scenarios with stakeholders. By adopting and improving these practices, European conservation planning might become more actionable and adaptable towards implementable policy outcomes. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.

Pioneer tree species accelerate restoration of tree-related microhabitats in 50-year-old reserves of Białowieża Forest, Poland

Retention of structural elements such as deadwood and habitat trees at the level of forest stands has been promoted to integrate biodiversity conservation into multiple-use forest management. The conservation value of habitat trees is largely determined by the presence, richness, and abundance of tree-related microhabitats (TreMs). Since TreMs are often lacking in intensively managed forests, an important question of forest conservation is how the abundance and richness of TreMs may be effectively restored. Here, we investigated whether the strict protection of forest through cessation of timber harvesting influenced TreM occurrence at tree and stand levels. For that purpose, we compared four managed and four set-aside stands (0.25 ha each) in the Białowieża Forest, with identical origin following clear-cuts approximately 100 years ago. We found that the abundance and richness of TreMs on living trees were not significantly different between stands that were either conventionally managed or where active forest management ceased 52 years ago. Yet, our analysis of TreMs on tree species with contrasting life-history traits revealed that short-lived, fast-growing species (pioneers) developed TreMs quicker than longer-lived, slower-growing species. Hence, tree species such as Populus or Betula, which supply abundant and diverse TreMs, can play an important role in accelerating habitat restoration.

European Forest Governance: Status Quo and Optimising Options with Regard to the Paris Climate Target

This article assesses and develops policy instruments for forest governance in the EU. Methodologically, it examines opportunities and limits for negative emissions by means of a literature review. On this basis, it conducts a qualitative governance analysis of the most important instruments of EU forest policy and presents optimizing policy options, measured against the binding climate and biodiversity targets under international law. Our analysis shows that the potential benefits of afforestation and reforestation for climate mitigation are overestimated, and are often presented as the new saviours to assist in reaching climate neutrality, inter alia, since only biodiverse and thus resilient forests can function as a carbon sink in the long term. Furthermore, we demonstrate that the existing EU law fails to comply with climate and biodiversity targets. Quantity governance systems for livestock farming, fossil fuels and similar drivers of deforestation represent a more promising approach to forest governance than the dominant regulatory and subsidy-based governance. They are most effective when not directly addressing forests due to their heterogeneity but central damaging factors such as fossil fuels and livestock farming. Selected aspects of regulatory and subsidy law can supplement these quantity governance systems when focusing on certain easily attainable and thus controllable subjects. These include, e.g., the regulatory protection of old-growth forests with almost no exceptions and a complete conversion of all agricultural and forest subsidies to “public money for public services” to promote nature conservation and afforestation.

Using historical spy satellite photographs and recent remote sensing data to identify high-conservation-value forests

High-conservation-value forests (HCVFs) are critically important for biodiversity and ecosystem service provisioning, but they face many threats. Where systematic HCVF inventories are missing, such as in parts of Eastern Europe, these forests remain largely unacknowledged and therefore often unprotected. We devised a novel, transferable approach for detecting HCVFs based on integrating historical spy satellite images, contemporary remote sensing data (Landsat), and information on current potential anthropogenic pressures (e.g., road infrastructure, population density, demand for fire wood, terrain). We applied the method to the Romanian Carpathians, for which we mapped forest continuity (1955-2019), canopy structural complexity, and anthropogenic pressures. We identified 738,000 ha of HCVF. More than half of this area was identified as susceptible to current anthropogenic pressures and lacked formal protection. By providing a framework for broad-scale HCVF monitoring, our approach facilitates integration of HCVF into forest conservation and management. This is urgently needed to achieve the goals of the European Union's Biodiversity Strategy to maintain valuable forest ecosystems.

Sacred oak woods increase bird diversity and specialization: Links with the European Biodiversity Strategy for 2030

Sacred groves in Greece are usually forest remnants with large trees around chapels, protected through centuries by Orthodox religion. We examined the comparative ecological value of 20 oak-dominated sacred groves vs managed oakwoods, in terms of their habitat characteristics and avian communities (passerines and woodpeckers). Sacred groves have maintained a more pronounced old-growth character than managed oakwoods in terms of average Diameter at Breast Height (DBH) and tree height. Besides holding significantly greater bird species richness and abundance, they supported greater functional richness, phylogenetic diversity, and phylogenetic bird species variability. Bird communities in sacred groves were more heterogeneous and showed greater avian specialization levels than in managed woods. Generalized Linear Models showed that the main factor positively affecting all aspects of bird diversity was DBH, while the abundance of dead trees increased bird abundance. Our results underline the importance of maintaining large-sized trees in forest management practices to support bird diversity and decrease biotic homogenization. Since the new European Biodiversity Strategy explicitly requires all remaining European primary and old-growth forests to be strictly protected by 2030, we argue that sacred groves, despite their small size, meet the criteria to be considered in the strict protection and restoration targets of the strategy, as primary old growth woods of high biodiversity value.

European primary forest database v2.0

Primary forests, defined here as forests where the signs of human impacts, if any, are strongly blurred due to decades without forest management, are scarce in Europe and continue to disappear. Despite these losses, we know little about where these forests occur. Here, we present a comprehensive geodatabase and map of Europe's known primary forests. Our geodatabase harmonizes 48 different, mostly field-based datasets of primary forests, and contains 18,411 individual patches (41.1 Mha) spread across 33 countries. When available, we provide information on each patch (name, location, naturalness, extent and dominant tree species) and the surrounding landscape (biogeographical regions, protection status, potential natural vegetation, current forest extent). Using Landsat satellite-image time series (1985-2018) we checked each patch for possible disturbance events since primary forests were identified, resulting in 94% of patches free of significant disturbances in the last 30 years. Although knowledge gaps remain, ours is the most comprehensive dataset on primary forests in Europe, and will be useful for ecological studies, and conservation planning to safeguard these unique forests.

Tree-Related Microhabitats Follow Similar Patterns but are More Diverse in Primary Compared to Managed Temperate Mountain Forests

The impact of forest management on biodiversity is difficult to scrutinize along gradients of management. A step towards analyzing the impact of forest management on biodiversity is comparisons between managed and primary forests. The standardized typology of tree-related microhabitats (TreMs) is a multi-taxon indicator used to quantify forest biodiversity. We aim to analyze the influence of environmental factors on the occurrence of groups of TreMs by comparing primary and managed forests. We collected data for the managed forests in the Black Forest (Germany) and for the primary forests in the Western (Slovakia) and Southern Carpathians (Romania). To model the richness and the different groups of TreMs per tree, we used generalized linear mixed models with diameter at breast height (DBH), altitude, slope and aspect as predictors for European beech (Fagus sylvatica (L.)), Norway spruce (Picea abies (L.)) and silver fir (Abies alba (Mill.)) in primary and managed temperate mountain forests. We found congruent results for overall richness and the vast majority of TreM groups. Trees in primary forests hosted a greater richness of all and specific types of TreMs than individuals in managed forests. The main drivers of TreMs are DBH and altitude, while slope and aspect play a minor role. We recommend forest and nature conservation managers to focus: 1) on the conservation of remaining primary forests and 2) approaches of biodiversity-oriented forest management on the selection of high-quality habitat trees that already provide a high number of TreMs in managed forests based on the comparison with primary forests.

Moderate- to High-Severity Disturbances Shaped the Structure of Primary Picea Abies (L.) Karst. Forest in the Southern Carpathians

Research Highlights: Past disturbances occurred naturally in primary forests in the Southern Carpathians. High- and moderate-severity disturbances shaped the present structure of these ecosystems, which regenerated successfully without forestry interventions. Background and Objectives: Windstorms and bark beetle outbreaks have recently affected large forest areas across the globe, causing concerns that these disturbances lie outside the range of natural variability of forest ecosystems. This often led to salvage logging inside protected areas, one of the main reasons for primary forest loss in Eastern Europe. Although more than two-thirds of temperate primary forests in Europe are located in the Carpathian region of Eastern Europe, knowledge about how natural disturbances shape the forest dynamics in this region is highly essential for future management decisions. Material and Methods: We established our study in a primary forest valley situated in the centre of the largest temperate primary forest landscape in Europe (Făgăraș Mountains). A dendrochronological investigation was carried out to reconstruct the natural disturbance history and relate it to the present forest structure. Results: The dendrochronological analysis revealed high temporal variability in the disturbance patterns both at the patch and stand level. Moderate severity disturbance events were most common (20–40% of canopy disturbed in 60% of the plots) but high severity events did also occur (33% of the plots). Regeneration was spruce-dominated and 71% of the seedlings were found on deadwood microsites. Conclusions: We conclude that the current structure of the studied area is a consequence of the past moderate-severity disturbances and sporadic high-severity events. The peak in disturbances (1880–1910) followed by reduced disturbance rates may contribute to a recent and future increase in disturbances in the Făgăraș Mts. Our findings show that these disturbance types are within the range of natural variability of mountain spruce forests in the Southern Carpathians and should not be a reason for salvage logging in primary forests from this area.

The Woody Planet: From Past Triumph to Manmade Decline

Woodiness evolved in land plants approximately 400 Mya, and very soon after this evolutionary invention, enormous terrestrial surfaces on Earth were covered by dense and luxurious forests. Forests store close to 80% of the biosphere’s biomass, and more than 60% of the global biomass is made of wood (trunks, branches and roots). Among the total number of ca. 374,000 plant species worldwide, approximately 45% (138,500) are woody species—e.g., trees, shrubs or lianas. Furthermore, among all 453 described vascular plant families, 191 are entirely woody (42%). However, recent estimations demonstrate that the woody domination of our planet was even greater before the development of human civilization: 1.4 trillion trees, comprising more than 45% of forest biomass, and 35% of forest cover disappeared during the last few thousands of years of human dominance on our planet. The decline in the woody cover of Planet Earth did not decelerate during the last few centuries or decades. Ongoing overexploitation, land use and climate change have pushed ten thousand woody species to the brink of extinction. Our review highlights the importance, origin and past triumph of woody species and summarizes the unprecedented recent decline in woody species on our planet.