Deliverable 2.1. Description of the applied CSF practices

CREAF. Campus UAB. Edifici C 08193 Cerdanyola del Vallès (Barcelona) Tel. + 34 93 581 13 12 [email protected] www.creaf.cat | blog.creaf.cat MONIMED - Monitoring Mediterranean climate-smart forestry practices for climate resilience and ecosystem service provision This research was supported by the project MONIMED (G-04-2024), funded by the European Union through FORWARDS (Horizon Europe Project No. 101084481) grants to third parties managed by European Forest Institute Deliverable 2.1. Description of the applied CSF practices Due date of deliverable: 22/03/2025 Actual submission date: 20/03/2025 Deliverable 2.1. Description of the applied CSF practices 2 Authors Diana Pascual Sánchez, Eduard Pla Ferrer, Mireia Banqué i Casanovas. Abstract This deliverable gives an in deep description of the forest management practices implemented in the project and of the previous conventional practices applied in the same areas. The objective is to characterise the initial conditions of the forest stands where the treatments will be or were implemented, as the basis to monitor the changes in the following years. The first section is a short introduction to the deliverable. The second section describes the forest management activity in Requesens, with a description of the initial conditions of the forest, the conventional practices applied in 2015, and the new practices applied in 2025. The third section reproduce the same information from the Montesquiu field trail and the fourth section for the Montnegre-Corredor trail. Citation Pascual D, Pla E, Banqué M (2025). Deliverable 2.1 Description of the applied CSF practices. MONIMED Project Revision Name of the version Writer/ Reviewer Data Description D2.1_Description_practices .docx Diana Pascual et al. 20/03/2025 First version of the DL delivered to EFIMED MONIMED_D2.1_Description Practices2_20251121.docx Diana Pascual et al. 21/11/2025 Second version of the DL included in an Open Science repository, mention to funding and Creative Commons license. Deliverable 2.1. Description of the applied CSF practices 3 Index 1. Introduction .............................................................................................................. 4 2. Holm oak forest in La Albera protected area (Girona) .......................................... 5 2.1. Initial characteristics of the Holm oak forest ....................................................... 5 2.2. Conventional silvicultural practices ..................................................................... 5 2.3. New Climate-Smart Forestry practices ............................................................... 7 2.4. Cost of the practices ......................................................................................... 10 3. Mixed forest of Pinus sylvestris and oaks in the Montesquiu natural park (Barcelona) .................................................................................................................. 11 3.1. Initial characteristics of the mixed forest ........................................................... 11 3.2. Conventional silvicultural practices ................................................................... 11 3.3. New Climate-Smart Forestry practices ............................................................. 14 3.4. Cost of the practices ......................................................................................... 16 4. Holm oak forest in the Montnegre-Corredor natural park (Barcelona) ............. 18 4.1. Initial characteristics of the Holm oak forest ..................................................... 18 4.2. Conventional silvicultural practices ................................................................... 19 4.3. New Climate-Smart Forestry practices ............................................................. 21 4.4. Cost of the practices ......................................................................................... 23 5. References .............................................................................................................. 24 Deliverable 2.1. Description of the applied CSF practices 4 1. Introduction Rural abandonment in recent decades, combined with climate change, has rendered Euro-Mediterranean Forest areas highly vulnerable to the impacts of climate change, thereby threatening the provision of ecosystem services. Historically, forest management in Mediterranean regions was characterised by high intensity, system simplification, and a single-product focus. Contemporary forest structures are the outcome of these historical trends, leading to management abandonment in highly vulnerable stands prone to drought, pest outbreaks, and wildfires. Over the past decades, several demonstrative projects have assessed the impact of forest management on the adaptive capacity of Mediterranean forests. These studies have focused on monitoring key indicators such as forest growth, tree vitality, and fire risk reduction following different thinning intensities and understory clearing treatments. This project seeks to advance adaptive forest management by integrating closerto-nature management strategies and incorporating novel parameters related to multifunctional management, biodiversity conservation, carbon sequestration potential, and climate resilience. The project encompasses the long-term monitoring of ongoing pilot sites under conventional management (10 and 5 years of monitoring) alongside newly established adjacent pilots implementing Climate-Smart Forestry (CSF) practices: (1) integrative multifunctional management and (2) management geared towards fostering natural development processes. All management approaches will be assessed using newly defined indicators reflecting the forest’s capacity to support biodiversity, its carbon sequestration potential, and its resilience to climatic stressors. This report gives an in deep description of the forest management practices implemented in the project and of the previous conventional practices applied in the same areas. The objective is to characterise the initial conditions of the forest stands where the treatments are implemented, as the basis to monitor the changes in the following years. The project is developed in the Mediterranean area of Catalonia (NE Spain), taking advantage of the existing network of CREAF pilots on adaptive forest management, including the most representative Mediterranean forest types (dominated by Quercus ilex, Quercus humilis and Pinus sylvestris). The field trials are established in three sites: - A Holm oak forest in La Albera protected area (Girona). - A mixed forest of Pinus sylvestris and oaks in the Montesquiu natural park (Barcelona). - A Holm oak forest in the Montnegre-Corredor natural park (Barcelona). Deliverable 2.1. Description of the applied CSF practices 5 2. Holm oak forest in La Albera protected area (Girona) The Holm oak (Quercus ilex) is one of the most representative evergreen oaks in the Mediterranean. The selection of the location in La Albera protected area responded to the high vulnerability of the area to climate change impacts, being a highly fire-prone forest remaining unmanaged for the last 80 years. The surrounding area experienced a 2012 wildfire, and a sudden change in wind direction was the only reason that this area was not burned. 2.1. Initial characteristics of the Holm oak forest Holm oak is the dominant species (80-90% of the basal area), accompanied by several other species, including cork oak (Quercus suber), downy oak (Quercus pubescens), Phillyrea angustifolia, and Erica arborea, among others. An initial inventory determined that this forest is highly dense (over 2,500 feet/ha, diameter at breast height higher than 7.5 cm), with a basal area of 31.5 m²/ha and an irregular structure. According to the estate owners, the forest has remained unmanaged for approximately 80 years. Figure 1 shows the initial characteristics of the forest. Figure 1. Initial characteristics of the Holm oak forest in Requesens. 2.2. Conventional silvicultural practices In 2015, as part of the LIFE MEDACC project (LIFE12 ENV/ES/000536, http://medacclife.eu/), two conventional silvicultural practices were applied in the site. The treatments had the main objective to reduce the fire risk and water stress through the reduction of tree density and the promotion of mature structures with bigger trees and fuel discontinuity. The practices were designed together with local stakeholders and the ownership, particularly with the public body in charge of forest management (Forest Ownership Centre, CPF), and with the Forest Science and Technology Centre of Catalonia (CTFC) according to the adaptive management guidelines compiled in ORGEST (Vericat, et al., 2011). Deliverable 2.1. Description of the applied CSF practices 6 In this site, three plots of about 1 ha were implemented in 2015: - Plot of low intensity treatment: Application of a low thinning clearing with the objective to adapt the forest to a regular structure. Regular forests are, in general, more efficient in the water use and in fire prevention. The intensity of the practice was: ➢ A 10%-reduction in basal area and a 18%-reduction in density, primarily affecting smaller diameter. The low thinning operation impacted 2-3 sprouts per stump. ➢ No changes in the canopy cover to prevent resprouting. - Plot of high intensity treatment: Application of a selection treatment and intense understory clearing to adapt forest to an irregular structure and to stimulate forest regeneration. Irregular forests are supposed to preserve better the sol, its quality and nutrients. The intensity of the practice was: ➢ A 33%-reduction in basal area and 43%-reduction in density. ➢ A 40%-reduction of canopy cover, to stimulate resprouting. - Control plot, with no intervention. Table 1 summarizes the initial density and basal area of each treatment area, the same numbers after the implementation of the forest management in 2015, and the percentage of change. Figure 2 and Figure 3 shows the final estate of the Holm oak forest after the two treatments. Table 1. Summary of the density and basal area per treatment, before the forest management, after the management and percentage of change. Density Basal area Treatment Pre-treatment (ft/ha) Post-treatment (ft/ha) Change (%) Pre-treatment (m2/ha) Post-treatment (m2/ha) Change (%) Control 2,164.5 2,164.5 - 32.8 32.8 - Low intensity 2,811.7 2,291.8 18% 28.1 25.4 10% High intensity 2,599.5 1,485.4 43% 33.5 22.5 33% Mean value 2,525.3 1,980.6 31.5 26.9 Deliverable 2.1. Description of the applied CSF practices 7 Figure 2. Estate of the Holm oak forest after the low intensity treatment. Figure 3. Estate of the Holm oak forest after the high intensity treatment. 2.3. New Climate-Smart Forestry practices The existing silvicultural practices were supplemented with two additional field trials within the framework of the MONIMED project. Two new 1-hectare plots were established in the field, where CSF practices were implemented between January and February 2025: - Close-to-Nature Silviculture Plot: This silvicultural approach involves applying targeted treatments to enhance tree species diversity, promote mixed stand structures and functional diversity, and regulate competition while simultaneously supporting the vitality of dominant trees, stimulating fruit production, and mitigating water competition. In this plot, an individual-tree silvicultural method has been employed, prioritizing the selection of high-quality trees for multiple objectives (biodiversity conservation, timber production, and natural regeneration). Specific silvicultural interventions have been applied to optimize their development, including reducing direct competition. Deliverable 2.1. Description of the applied CSF practices 8 Site-specific factors such as soil characteristics, light availability, and species composition have guided the applied treatments. This method aims to balance sustainable yield with biodiversity conservation while maintaining key ecosystem functions. At this stage of the project, treatment intensity has not yet been quantified. However, the plots will be reassessed at the project's conclusion to enable precise characterization of the applied interventions. - Plot of preparation to natural dynamics in non-productive stands: This intervention aims to promote forest maturity and restore complex ecological processes by minimizing human influence. The following actions were implemented: o Increasing coarse woody debris stocks both on the forest floor (through tree felling) and standing (via tree girdling). o Enhancing the vitality and dimensions of larger-diameter trees by alleviating direct competition, thereby contributing to biodiversity conservation and structural maturity. o Promoting vertical heterogeneity by creating small canopy openings within the forest. Figure 4 and Figure 5 shows the final estate of the Holm oak forest after the new CSF practices. Figure 4. Estate of the Holm oak forest after the closer-to-nature silviculture. Deliverable 2.1. Description of the applied CSF practices 9 Figure 5. Estate of the Holm oak forest after the preparation to natural dynamics. Figure 6 shows the location and shape of the four treatment plots and the control plot in Requesens. Figure 6. Location of the treatment plots (red polygons) in Requesens. Deliverable 2.1. Description of the applied CSF practices 16 Figure 13. Location of the treatment plots (red polygons) in Montesquiu. 3.4. Cost of the practices The total costs of the practices are included in Table 5. The costs need to be referenced to the year when actions were implemented to make comparisons. Table 5. Implementation costs of the practices. Treatment Implementation costs (€/ha) Year of execution Low intensity treatment (T1) 1,920 €/ha 2015 High intensity treatment (T2) 3,620 €/ha2 2015 Pine substitution treatment (T3) 2,800 €/ha 2015 Closer-to-nature treatment (T4) 1.268 €/ha 2025 Preparation to natural dynamics (T5) 500 €/ha 2025 2 The costs/ha in treatment 2 in Montesquiu is higher than expected due to was necessary to open two extraction lines to pull out the wood. Deliverable 2.1. Description of the applied CSF practices 17 The forest treatments have produced different products that are sold to obtain benefits, as included in Table 6. Table 6. Benefits of the obtained products. Treatment Firewood / biomass Wood Paper wood Total benefits € Benefits €/ha Year of execution tones €/tone tones €/tone tones €/tone Low and High intensity treatment (T1-T2) and pine substitution (T3)3 11.2 28 43.2 38 21.4 20 2,383.2 € 794.4 €/ha 2015 Closer-to-nature treatment (T3) 17.0 70 3.7 45 1,356.6 € 1,356.6 €/ha 2025 Preparation to natural dynamics (T4) - - - - - - - - 2025 3 The products obtained in 2015 are cumulative for all treatment areas, and the results are not differentiated by treatment. Deliverable 2.1. Description of the applied CSF practices 18 4. Holm oak forest in the Montnegre-Corredor natural park (Barcelona) The Holm oak (Quercus ilex) is one of the most representative evergreen oaks in the Mediterranean. The selection of the location in Montnegre-Corredor natural park responded to the high vulnerability of the area to pests, forest fires and droughts. The Montnegre-Corredor area as a whole and specifically the pilot study area has been significantly affected by pests. On the one hand, the pine forests are in a state of general decline due to the interaction of various factors, such as the orography, forest management of the area, repeated episodes of drought, etc. This decline triggered a serious infestation of the Tomicus destruens bark beetle in stone pines (Pinus pinea) from 2015 to 2018, leading to the death of many of them. Maritime pine has also been affected by the sucking insect Matsococcus feytaudii, which weakens it and increases its vulnerability to bark beetles. In terms of fire prevention, the massif is part of the priority firebreak area, B3 Serra del Montnegre i el Corredor. Moreover, the specific area where the actions were implemented is a key fire prevention zone: it is within a Priority Management Area (AGP), more specifically in a Strategic Management Point (PEG in its Catalan acronym), meaning, in a zone where fuel modification and/or infrastructure preparation allows the fire service to carry out safe attack manoeuvres that reduce the spread of large forest fires. 4.1. Initial characteristics of the Holm oak forest The Holm oak (Quercus ilex) forest is in Montnegre-Corredor natural park (Barcelona), in the private estate of Can Bordoi, that has remained untouched for the past 20 years. The forest is made up of a holm oak grove scattered with cork oak and small patches of stone pine and an undergrowth of tree heather and strawberry trees. The presence of holm oak varies and is distributed in patches, with some that are denser and others that have more tree heather and strawberry trees. The initial forest showed a high fraction of canopy cover (CC of 84 %), high density (1,122 ft/ha) and basal area (25.3 m2/ha) (Figure 14). Deliverable 2.1. Description of the applied CSF practices 19 Figure 14. Initial characteristics of the Holm oak forest in Montnegre-Corridor. 4.2. Conventional silvicultural practices In 2020, as part of the Interreg Sudoe MONTCLIMA project (https://www.montclima.eu/en), a conventional silvicultural practice was applied in the site. The treatment had the main objective to reduce the forest stand’s vulnerability to fire based on improving its resistance and resilience to disturbances, increasing the complexity of its structure and composition. The practices were designed together with the Association of Forest Owners of the Montnegre-Corredor, in charge of the forest management of the Can Bordoi ownership. The applied silviculture followed an irregular forest management model, involving gentle but frequent thinning was applied. This model considered that the application of a treatment is necessary when a basal area of at least 25 m2/ha is reached, which typically occurs in the massif every 10 years (rotation period) (Guitart , et al., 2022). Therefore, the silvicultural treatments implemented consisted of the following actions: 1. Thinning: gentle felling in patches of holm oak and the densest patches of stone pine, according to the following criteria: Selection of the healthiest and most robust trees of all ages; promotion of secondary or accompanying species, favouring biodiversity; fostering of the vertical discontinuity between strata through the extraction of trees; favouring of a homogeneous distribution and seed-bearing trees; ensuring the presence of regenerated areas and abundant stands of younger types of trees across the entire area; maintaining the remaining basal area equal to or greater than 20 m2/ha and a maximum reduction of 25 %; and maintaining a high residual CC (70-80%). 2. Coppice management: focused on younger oak trees to reduce competition among resources, concentrating growth in the trees that are best developed and positioned. Between 1 and 3 sprouts were selected per stump. 3. Selective clearing: reduction of shrub-level competition with tree regeneration, to favour certain shrub species that have value for the biodiversity and modify the vertical Deliverable 2.1. Description of the applied CSF practices 20 and horizontal structure of the fuel layers to reduce vulnerability to fires. This involves a partial elimination of the shrub layer, considering the following criteria: scrub CC < 30 %; height < 1.3 m; coppice method applied to tree-like shrubs, such as tree heather and strawberry trees, maintaining the best developed and best positioned (1-3 sprouts/stump); and removal of flammable species and promotion of species that provide protection and/or food for fauna. With this framework, two plots were implemented in 2020: - Plot with an irregular forest management model (5.4 ha): In terms of forest structure, these treatments have led to: ➢ A 14%-reduction in canopy cover, 19%-reduction in density and 8%-reduction in basal area. ➢ A 77%-reduction scrub cover and a 97%-reduction in fuel biovolume. - Control plot (1.9 ha), with no intervention. Table 7 summarizes the initial density and basal area of each treatment area, the same numbers after the implementation of the forest management in 2020, and the percentage of change. Figure 15 shows the final estate of the Holm oak forest after the treatment. Table 7. Summary of the density and basal area per treatment, before the forest management, after the management and percentage of change. Density Basal area Treatment Pre-treatment (ft/ha) Post-treatment (ft/ha) Change (%) Pre-treatment (m2/ha) Post-treatment (m2/ha) Change (%) Control 1199.0 1199.0 29.0 29.0 Treatment 1075.0 872.0 19% 23.1 21.4 8% Mean value 1137.0 1035.5 26.1 25.2 Deliverable 2.1. Description of the applied CSF practices 21 Figure 15. Estate of the Holm oak forest after the treatment. 4.3. New Climate-Smart Forestry practices The existing practices were complemented with two more field trials in the framework of the MONIMED project. Two new plots of 1 hectare were defined in the field, where CSF practices were implemented along December 2024 and January 2025: - Close-to-Nature Silviculture Plot: The same treatment as Requesens forest was applied. - Plot of preparation to natural dynamics in non-productive stands: The same treatment as in Requesens forest was applied. Figure 16 and Figure 17 shows the final estate of the Holm oak forest after the new CSF practices. Figure 16. Estate of the Holm oak forest after the closer-to-nature silviculture. Deliverable 2.1. Description of the applied CSF practices 22 Figure 17.Estate of the Holm oak forest after the preparation to natural dynamics. Figure 18 shows the location and shape of the four treatment plots and the control plot in Montnegre-Corredor. Figure 18. Location of the treatment plots (red polygons) in Montnegre-Corredor. Deliverable 2.1. Description of the applied CSF practices 23 4.4. Cost of the practices The total costs of the practices are included in Table 8. The costs need to be referenced to the year when actions were implemented to make comparisons. Table 8. Implementation costs of the practices. Treatment Implementation costs (€/ha) Year of execution Irregular model treatment (T1) 1,573.1 €/ha 2020 Closer-to-nature treatment (T2) 3,590.3 €/ha4 2025 Preparation to natural dynamics (T3) 577.6 €/ha 2025 The forest treatments have produced different products that are sold to obtain benefits, as included in Table 9. Table 9. Benefits of the obtained products. Treatment Firewood / biomass Paper wood Total benefits € Transport costs € Benefits €/ha Year of execution tones €/tone tones €/tone Irregular model treatment (T1) 61.9 66.6 - - 4,126.92 € 1,055.0 € 568.9 €/ha 2020 Closer-to-nature treatment (T2) 31.23 65.0 5.66 30.0 2,199.8 € - 2,199.8 €/ha 2025 Preparation to natural dynamics (T3) - - - - - - - 2025 4 This cost includes project supervision and tree marking. Deliverable 2.1. Description of the applied CSF practices 24 5. References Guitart , L., Pascual, D. & Pla, E., 2022. Pilot study report: Implementation of adaptive forest management as a tool for reducing the risks of fire and drought in midmountain holm oak forests., s.l.: Interreg SUDOE MONTCLIMA Project. Vericat, P., Piqué, M., Beltrán, M. & Cervera, T., 2011. 2011. Models de gestió per als boscos d’alzina (Quercus ilex subsp. ilex) i carrasca (Quercus ilex subsp. ballota): producció de fusta i prevenció d’incendis forestals. s.l.:Sèrie: Orientacions de gestió forestal sostenible per a Catalunya (ORGEST). Centre de la Propietat Forestal. Departament d’Agricultura, Ramaderia, Pesca, Alimentació i Medi Natural. Generalitat de Catalunya. .