Institute of Forestry

Afforestation and reforestation (A&R) are central components of current climate mitigation strategies and hold substantial potential for supplying biomass. However, large uncertainties remain regarding their actual mitigation potential, with considerable variation across global estimates, partly due to methodological differences. This study refines existing estimates of A&R potential by integrating temporal dynamics, climate change impacts, and land-use competition within a deliberately conservative framework.We combine climate-sensitive forest biome projections with current land-use cover data to assess global A&R potentials under three representative concentration pathways (RCP 2.6, 4.5, and 8.5) up to 2080 at a spatial resolution of 1 × 1 km. To account for land-use competition, A&R is restricted to non-managed pastureland. Potential biomass production and associated carbon sequestration are estimated using region-specific growth data in accordance with IPCC guidelines.Across all RCPs, we identify 731 million hectares globally as suitable for A&R through 2080. Relative to the historical baseline, climate change scenarios lead to a a net reduction of up to 24 million hectares of potential A&R area. While global potentials decline, regional patterns diverge markedly: boreal regions experience an increase in suitable area (+34 million hectares), whereas tropical and temperate regions exhibit substantial reductions (–33 and -18 million hectares, respectively). The A&R potentials presented here are intentionally conservative with respect to climate uncertainty, land-use competition, and long-term viability. Integrating these estimates with complementary scientific assessments is essential to underpin the feasibility of current climate policy targets and to support robust projections of biomass availability for scaling up the bioeconomy.If implemented in accordance with local ecological conditions, the identified A&R potentials can inform policy responses to climate-related risks and may contribute to climate mitigation while supporting a biomass supply as a substitute for fossil-based products. However, successful implementation requires careful consideration of resource constraints (e.g., water availability) and future abiotic and biotic risks.

IntroductionAccurate estimation of individual tree aboveground biomass (AGB) is essential for tree species selection, carbon accounting, and precision forestry. Unmanned aerial vehicle (UAV) LiDAR provides rapid access to detailed tree structural information, offering a promising tool for high-frequency biomass assessment.MethodsIn this study, a nonlinear mixed-effects (NLME) model integrating UAV LiDAR and field measurements was developed to quantify the influence of genetic heterogeneity and environmental factors on AGB estimation of Catalpa bungei. Data from 2,941 trees across 79 genotypes were collected in Henan Province, including LiDAR-derived tree height (LH), LiDAR-derived crown diameter (LCD), and AGB. By incorporating genotype as a random effect and planting density as a dummy variable, the NLME model significantly outperformed traditional dummy-variable models.ResultsGenotype effects explained significant AGB variation, achieving high accuracy (R²=0.7916, RMSE = 3.7095) and reducing TRE by 23.29% compared to the basic power function model. Leave-one-genotype-out cross-validation confirmed robustness. Calibration with the four largest trees yielded the best performance (TRE = 13.09%), while a simplified scheme using only two trees per genotype maintained high accuracy (TRE = 13.24%), markedly reducing field effort.DiscussionThese results highlight the superiority of NLME AGB models over linear approaches and demonstrate that accounting for genotype effects is critical for reliable biomass estimation. The proposed framework provides an efficient and cost-effective solution for biomass monitoring, tree breeding, carbon sink assessment, and precision forestry.

Conserving tigers (Panthera tigris) in human-dominated landscapes requires careful management of human-tiger conflict. Tiger attacks on human are the extreme form of conflict occurring primarily during livelihood activities in the Terai arc landscape of Nepal. We assessed spatio-temporal patterns of tiger attacks on human and factors associated with human fatality due to attacks. We collected human tiger conflict data from the government authorities, primarily national park offices and division forest offices. We interviewed 245 victims or family members attacked by tigers between 2010 and 2024 using a semi-structured questionnaire. Most tiger attacks on human (>90%) occurred inside forest areas and over half were fatal. Men were attacked more frequently (65.3%) but fatality was higher among women (>70%). Majority of the victims (93%) were illiterate or had a low level of education and 62% were hill migrants while indigenous Terai peoples were less frequently (27%) attacked. Large number of the tiger attacks occurred during resource collection from forests or livestock herding. The victim’s group size, sex and posture during the tiger attacks affected human fatality. Tiger attack can be minimized by applying adaptive management of buffer zone and corridor forests, adopting safety protocols through behavior change campaigns, promoting alternative livelihoods and tiger tourism, and proactive management of conflict-causing tigers. The finding of this research has long term implications to strengthen human-tiger coexistence in human-dominated landscapes in Nepal and elsewhere. Keywords: Tiger attack, Human-tiger-conflict, Co-existence, Terai-arc-landscape, Nepal

Thermo-hydro-mechanical (THM) densification is an effective method for improving the mechanical performance of low-density, fast-growing hardwoods such as poplar. This study examined the bending performance of THM-densified poplar wood at different compression ratios (CR = 0%, 50%, 60%, and 65%), with emphasis on the effects of ultrasonic pretreatment (US) and thermal modification posttreatment (TM), applied individually and in combination. A paired sampling design was used to reduce material variability, and modulus of rupture (MOR) and modulus of elasticity (MOE) were evaluated using linear mixed-effects models (LMM). Bending tests were performed in accordance with EN 310:1993. Increasing the compression ratio led to substantial increases in MOR and MOE; compared with non-densified specimens, MOR increased by approximately 240% and MOE by about 140% at CR = 65%, confirming densification as the dominant factor controlling bending performance. US did not affect non-densified wood but significantly enhanced MOR and MOE after densification, particularly at CR = 50%. In contrast, TM consistently reduced MOR and, to a lesser extent, MOE across all compression ratios. The results demonstrate that the bending performance of densified poplar wood is governed by both compression ratio and compression-dependent treatment effects.

Leaf rust caused by Melampsora caprearum is one of the most important but understudied diseases of goat willow (Salix caprea). This research studied for the first time the effect of genotype and the morphology of goat willow leaves on the occurrence and abundance of Melampsora caprearum uredinia. The genotype showed a statistically significant impact on the occurrence and abundance of uredinia on goat willow leaves. The morphological characteristics of the leaves, leaf area, leaf circumference, and length and width of the leaves had a statistically significant effect on the occurrence of uredinia, while they did not impact the uredinia abundance on the leaves. On the same tree, leaves of larger dimensions showed greater resistance to the occurrence of infection symptoms. Based on leaf morphology, the results represent a realistic basis for selecting goat willow trees less susceptible to Melampsora caprearum. Measures that can be applied in goat willow habitats to regulate leaf dimensions and reduce damage from Melampsora caprearum are discussed.

Somatic embryogenesis (SE) represents the most efficient and scalable technology for the mass clonal propagation and genetic improvement of superior conifer genotypes, which is crucial for meeting global wood demand and supporting forest adaptation to climate change. Despite its immense potential, SE in the genus Pinus still faces major limitations, including low initiation frequencies, restricted explant availability, and pronounced genotype dependence. This review synthesizes current knowledge on the factors influencing SE in Pinus species, with a specific focus on two ecologically vital Tertiary relicts endemic to the Balkan Peninsula: Pinus peuce (Macedonian pine) and Pinus heldreichii (Bosnian pine). For these species, traditional vegetative propagation methods are difficult or ineffective, making SE the priority approach for clonal propagation. Detailed studies on these species revealed that SE induction is highly dependent on the explant type and developmental stage. Successful embryogenic tissue formation was achieved only from whole megagametophytes containing immature zygotic embryos, within a narrow developmental window spanning 4-10 weeks post-fertilization. Furthermore, medium composition, particularly reduced ammonium concentration, proved critical for P. heldreichii success. These findings underscore the need for continued, species-specific optimization to overcome current bottlenecks and realize the full potential of SE for the conservation and sustainable clonal forestry of these high-value pines.

The Bioeconomy Roadmap of the Republic of Serbia defines a strategic framework for advancing the green transformation of agribusiness through sustainable resource use, circularity, and innovation. This paper aims to present the relevance of the Roadmap for agriculture and biomass- based value chains. The document was developed through a multi-actor co-creation process involving public institutions, research organization, industry, and civil society, utilizing analytical reviews and participatory consultations. The main results include the identification of key barriers to bioeconomy implementation, including institutional and policy gaps (limited readiness of institutions, insufficient policy support and the need for policy adjustments), knowledge and technological limitations (low awareness of bioeconomy, technological and digital constraints), and financial constraints, as well as five priority action areas: institutional strengthening, international cooperation, sustainable management of biological resources, support for circular bio-based production, and development of innovative biotechnologies. The road map provides a governance and implementation model that can enhance resource efficiency, strengthen bio-based value chains and improve resilience of the agribusiness sector. The conclusions emphases the need for integrated policies, targeted investments, and knowledge transfer to accelerate Serbia’s transition toward a competitive, low-carbon agricultural system aligned with EU objectives.

Soil contamination is a major contemporary issue. In light of increasing efforts to align seedling production with the sustainable use and preservation of soil resources, this study aimed to explore the potential of selected plant-growth-promoting bacteria as natural alternatives to mineral fertilizers, a major soil pollutant in the forestry sector. The experiment involved inoculating one-year-old sessile oak (Quercus petraea) seedlings with multiple single bacterial treatments and a consortia derived from sessile oak rhizosphere and monitoring their effects on plant physiological parameters such as chlorophyll, carotenoid, and nitrogen content, along with selected parameters of the rapid chlorophyll a fluorescence induction curve (an OJIP curve). The results indicated that the selected bacterial strains improved specific plant physiological parameters at certain points during the monitoring period; however, further research is necessary to draw statistically significant conclusions. Although these bacteria did not directly enhance photosynthetic parameters, their potential remains evident and could be harnessed through improved application methods. Future studies should focus on identifying site conditions that support the proliferation of the introduced bacterial populations.

Abstract The successful implementation of climate change (CC) policies and strategies in forestry and related sectors (nature conservation, environment, energy) may be hindered by a lack of appropriate regulatory, economic and informational policy instruments, weak cross-sectoral coordination, and limited stakeholder collaboration during their implementation. This study aims to assess opportunities to improve policy instruments and collaboration for CC governance in the forestry and related sectors in selected forest regions and national parks in Serbia. Data were collected in 2022 through 23 interviews with decision-makers, public and civil sector experts, and representatives of “good practice” examples of stakeholder collaboration in CC. The majority of respondents (87%) support the improvement of regulatory instruments through the development of agreements with local self-governments and different public and civil organizations, and outreach plans in forestry and related sectors. A large number of respondents (70%) advocate for greater variety of economic policy instruments involving local self-government in knowledge sharing programs and creating additional incentives for private forest owners. Informational policy instruments were endorsed by 91% of respondents, who emphasized the importance of local information exchanges, workshops, and forums to enhance community knowledge on CC governance. The majority of public and civil sector representatives (87%) recommend establishing cross-sectoral forums to improve dissemination of information and contacts between stakeholders. All respondents agree with the inclusion of civil sector representatives in the work of emergency management departments. Further research could investigate the feasibility of proposed solutions in the broader Serbian context among a wider group of stakeholders.