Aim of study: The objective was to evaluate an optimized model for the distribution and sequencing of machines in tree felling and processing and extraction operations, aiming to reduce unproductive times and gains in production capacity. Area of study: The study was conducted in a cellulose and paper company in the state of Parana, Brazil, in operational areas of the wood harvesting. Material and methods: The times of tree felling, processing and extraction were obtained from a harvester (hv) and a forwarder (fw) to estimate the operational efficiency and productivity of the system. At the same time, vector features equivalent to the set of plots in the area, roads and a matrix feature of the digital terrain model were obtained from a geographic database for estimation of a matrix of distances between the plots. The Ward method of hierarchical grouping was used based on the matrix of distances between the fields to form two work groups (GI and GII). For each working group, the shortest walking sequence was estimated using the Kruskal algorithm. Main results: An optimized distribution of 3 hw and 2 fw was necessary in GI to achieve the production target of 200 m³ PMH-1, with the machines covering a distance of 2,335 m. The proportion of machines 3 hw and 3 fw was needed in GII with a distance covered of 2,878 m. The proposed model optimized the number of machines and provided a 26.7% reduction in the total displacement of machines. Research highlights: The high cost of wood harvesting operations requires the use optimized of the forestry machines. The proposed model made it determine with efficiency the machines distribution and sequencing for a wood harvesting optimized. The model can be implemented in the operational planning in the forestry companies in more complex wood harvesting scenarios.

Aim of study: Analyze the behavior and predictive capacity of different non-destructive testing (NDT) methods—ultrasound, longitudinal and transverse vibrations, and static bending— for estimating the MOEGTO in two species of great forestry interest in Europe: Pinus sylvestris and Populus × euramericana. Additionally, this study focuses on developing global prediction models for MOEGTO using the NDT modulus of elasticity from both species, and on improving the reliability of prediction through the cross-validation process. Area of study: Provenance Region 8 (Northern Iberian System, Spain) and Ribera del Carrión (Palencia, Spain). Material and methods: A total 75 sawn lumber samples (45 of Pinus sylvestris and 30 of Populus x euramericana) with dimensions of 60 × 40 × 1200 mm were analyzed using ultrasonic testing, longitudinal and transverse vibration methods, and both destructive and non-destructive static bending tests performed with a universal testing machine. Regression models were developed to predict the static modulus of elasticity (MOEGTO). Main results: The prediction model using the NDT method of longitudinal vibrations with Fast Fourier Transform (FFT) software for Pinus sylvestris showed the highest coefficient of determination with R2= 0.56, while for Populus × euramericana, the ultrasound method with the Sylvatest 4 device yielded R2= 0.67. For both species, the best-fit global prediction model was obtained with the ultrasound method using the Sylvatest Trio device, achieving R2= 0.60. Additionally, the application of cross-validation improved the predictive performance of the global models, particularly for the three ultrasound methods and the longitudinal vibration method, all of which attained R2 values above 0.6. Research highlights: This study confirms the reliability of ultrasound and longitudinal vibration techniques for estimating MOEGTO and contributes new insights by comparing multiple NDT methods across two species and developing robust cross-validated global prediction models.

Aim of the study: To determine if the decline of a Pinus sylvestris L. stand is due to pine wilt disease. Area of study: This research was conducted in the Agricultural and Phytopathological Laboratory of Galicia, LAFIGA (AGACAL, Xunta de Galicia). Material and methods: Six decaying P. sylvestris trees were sampled for Bursaphelenchus xylophilus detection. Morphological and molecular tools were applied for nematode identification according to the EPPO protocols. Main results: The nematode B. xylophilus was detected for the first time in P. sylvestris trees under natural conditions in Spain. Research highlights: It is confirmed the serious threat posed by pine wilt disease to P. sylvestris stands.

Aim of the study: A meta-analysis was applied to evaluate surface runoff and soil loss after fires of different severity and post-fire treatments in semi-arid forests of Central Eastern Spain. Area of study: Four sites (Lezuza, Agramón, Liétor and Ayna) were identified in Castilla-La Mancha and were monitored throughout 10 years at the plot and event scale. Material and methods: Rainfall simulations and observations after natural rainfalls were carried out to measure surface runoff and soil loss in unburned sites, burned and untreated sites, and burned sites treated with post-fire management techniques. The log response ratio of runoff and soil loss was calculated at the same site in order to evaluate the hydrological response to fire and post-fire management. Main results: The meta-analysis has shown: (i) prescribed fires do not noticeably increase runoff, while wildfires at every severity is able to trigger erosion, except in the case of low-severity fires and less intense rainfall; (ii) runoff generation capacity of burned soils is higher after moderate rainfalls; (iii) fire changed soil erodibility according to rainfall intensity between unburned and burned soils; (iv) in general, the evaluated treatments were not effective at reducing surface runoff (except for mulching using wood chips and manual logging); (v) in contrast, soil erosion under burned conditions decreased after almost all techniques, especially with mulching using Loranthus europaeus J. and wheat straw; (vi) the mulch made of the latter substrate (combined with manual logging or not) seems to be the most feasible post-fire anti-erosive action. Research highlights: Forest managers should prioritise areas potentially affected by high-severity wildfires for fire prevention. The most effective post-fire management technique is mulching, using wheat straw and wood chips to mitigate soil erosion and surface runoff, respectively.

Aim of study: We aimed at identifying differences in the response to water shortage between Eucalyptus globulus clones. Area of study: Field trials were established in SW Spain. Material and methods: Potted plants from six clones were grown in a greenhouse for 35 days under two watering regimes. Two clones were F0 genotypes and the other four were F1 (hybrid) genotypes, including one inbred clone. Differences in stomatal conductance, hydraulic traits, growth and specific leaf area (SLA) were analyzed. Main results: Water shortage decreased SLA, growth in height and leaf area and leaf-specific hydraulic conductivity (KLmax). We measured the highest growth in F1 genotypes and the lowest in the clone in which SLA was lowest. The inbred clone showed the highest growth reduction under water shortage. There was substantial hysteresis between leaf water potential (Y) and native embolism, most probably a result of combined cavitation and refilling. High losses of hydraulic conductance were compatible with high stomatal conductances. Maximum values of stomatal conductance decreased with the soil water content estimated from predawn Y and were lowest in the inbred clone, showing less plasticity and a diminished ability to cope with high temperatures, which could explain its poor development under field conditions. Research highlights: Soil water content and predawn Y appeared as critical factors controlling stomata closure, while stomatal conductance and SLA could be useful to predict differences in growth and survival from early trials.

Aim of study: To characterize the colonization of Pinus herrerae roots in trunks of dead standing trees and to evaluate the composition of roots and decomposing tissues of standing dead trees. Area of study. Jaguariaíva, Paraná state, Southern Brazil. Material and methods: This study evaluated root attributes in the soil, litter, and trunks of dead standing trees and the composition of wood and bark of trees. Root traits (length, mass mycorrhizal colonization, and mean nutrient concentrations), soil and organic layers, and mean nutrient concentrations of wood and bark for were analyzed by non-parametric test. Main results: Approximately 2 to 3.5 years after tree death, roots of adjacent trees in F and H horizon litter migrate into the wood/bark interface. Eight and a half years after tree death, roots of adjacent trees reached up to 3.3 m above the litter surface. At the wood/bark interface, a root mantle formed (length greater than 1 km m-2) with ~5% ectomycorrhizal colonization. Root presence in the wood/bark interface reduced P, K, and Fe concentration of dead wood and Zn concentration in bark. Research highlights: Our results indicate that roots of P. herrerae are capable of colonizing dead tree trunks as a nutrient resource pool. This nutrient acquisition mechanism may function as a shortcut in the biogeochemical cycling of nutrients in forest systems.

Aim of study: Wild mushrooms are among the most widespread non-wood forest products in the Mediterranean region contributing to the rural economies. However, the wild mushroom sector still faces problems along its supply chain that can compromise its future in a scenario of increasing demand. The aim of this study was to analyse the current epigeous wild mushroom sector. Area of study: Representative countries of the Mediterranean region: Spain, France, Italy, Croatia and Greece. Materials and methods: The analysis was carried out through a structured Delphi survey conducted in two rounds, with a questionnaire divided into four groups: 1) supply chain description, 2) sectorial SWOT analysis, 3) future challenges and 4) sectorial resilience increase. The Delphi survey started with the selection of an expert panel that included 14 representatives of the wild mushroom supply chain such as forest owners, mushroom pickers, processing industry and consumers. Main results: The results obtained from the expert panel confirmed the complexity of the wild mushroom supply chain with the following sectorial challenges: i) Traceability and sustainability is fundamental for the final consumer, ii) Sectorial administration should be more coordinated, iii) Mushroom picking should be regulated, as the grey market will decrease. Research highlights: The study identified the most important actions that will strengthen the links among sectorial actors and interconnect gastronomy with mushrooms sector. The creation of a common EU list of commercial mushroom species and the development of a taxation system together with the product traceability were also addressed.

Aim of study: Although beech (Fagus sylvatica L.) forests in north-western Spain constitute c.a. 40% of the total area occupied by the species in the whole country, no growth or yield studies have been carried out regarding these forests. The specific objective of this study was to elaborate yield tables and stand density management diagrams for the beech forests. Area of study: Asturias and León provinces (NW Spain). Material and methods: Sample plots (n=112) were established in natural beech forests, and 60 dominant trees were felled for sampling. The Asturias Government Forest Service provided data on another 351 felled trees. Yield tables and stand density management diagrams (SDMDs) were elaborated to estimate tree volume and biomass in the study area for the first time. Main results: These forests are more productive than expected. Although they are currently not managed for forestry purposes, they could be managed again in the future and the tools are now available for this purpose. Research highlights: The study generates new user-friendly tools to manage beech forests in northwestern Spain. These tools will also enable simulations to be conducted to determine the potential carbon storage or the capacity of the stands to sequester atmospheric carbon.

Aim of study: To investigate the impact of allochthonous material from piscivorous birds on forest soil microarthropod communities. Area of study: Six study zones in the Curonian Spit peninsula (western Lithuania) were designated in Pinus sylvestris stands with nesting sites of the great cormorants, taking into account the relief and the duration of the ornithogenic impact. Materials and methods: The total abundance of mites and Collembola and the species richness and diversity of Oribatida and Gamasina mites were assessed and compared. Main results: The abundance of Collembola, Tarsonemidae and Acaridae mites positively correlated with ornithogenic activity, while Oribatida and Gamasina mites decreased significantly. The structure of microarthropod communities was similar in most of the studied zones, except for the active nesting zone and the abandoned part of the colony on the dune slope. The greatest species richness of Oribatida and Gamasina was found in the unaffected forest in the dune hollow, whereas the lowest value was found in the active nesting area and in the abandoned part of the colony on the dune slope. Of the environmental parameters studied, soil pH (r = - 0.725) and tree layer (r = 0.827) were those most significantly related to the changes of microarthropod communities. Research highlights: We found that cormorant colonies have a strong impact on forest ecosystems and soil properties, leading to significant changes in soil microarthropod communities. Birds thus create a natural disturbance experiment that can help reveal the factors that determine the diversity and composition of natural microarthropod communities.

Aim of study: To explore the different patterns of fine-root traits by elucidating changes in their chemistries and morphologies in Chinese fir plantations along an altitudinal gradient. Area of study: National Mazongling Nature Reserve (Anhui Province). Material and methods: Soil and fine roots (≤ 2 mm) samples were extracted from three soil layers (0-10 cm, 10-20 cm, and 20-30 cm) at four altitudes (750 m, 850 m, 1000 m, and 1150 m), after which their nutrient concentrations and morphological traits, respectively, were quantified. We employed mixed model ANOVA to test the effects of altitude, soil layer, and their interactions on the characteristics of soil and fine roots. The relationships between the functional traits of fine roots and climate, soil and stand structures were evaluated by the standard major axis regression and the structural equation model. Main results: The chemical traits of fine roots were higher at medium altitudes (which decreased significantly with the soil layer). In contrast the morphological traits of fine roots did not change significantly. In chemical traits, both altitude, organic matter components, and soil total phosphorus (TP) exerted dominant effects on fine-root N, and both altitude and soil TP exerted dominant effects on fine-root P. However, in morphological traits, we found that altitude and soil C:N were crucial impact factors. Research highlights: Fine roots might preferentially adjust their chemical traits rather than morphological traits to facilitate higher root efficiencies in response to variable environmental conditions.