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Identifying effective methods for harvesting wood in short-rotation planted forests has recently become challenging, especially when trying to balance differing perspectives on the issue. In addition, practice in such forests may be highly variable from one place to another, and models are required to better understand the effectiveness of planted forest management and to make better decisions. A simulation experiment was setup in this study to understand how the productive performance of farm tractors, which is a common technical option in Thailand, is affected when extracting small-sized eucalyptus payloads sourced by very short cycles. Two tractors (hereafter T1 and T2) of different class size and fitted with backhoe grapples were selected and monitored via GNSS. Operational events were extracted from GNSS data, and were characterized by their speed, while payload size was estimated based on manual measurement done in the field. Then, simulations were carried out to see how moving speed and payload size may affect the productive performance as a function of extraction distance. Significant differences (α=0.05) in speed and payload size led to substantial variations in performance as the extraction distance increased. For instance, the number of daily work cycles were similar for both machines in a distance range of up to 100 m; daily production (m3), productivity (m3/h), and efficiency (h/m3), on the other hand, have shown important differences, with the higher size class T1 being more performant. Payload size and moving speed had a strong effect on efficiency, tripling the unit time for T2 at a distance of 1000 m. These findings have important consequences, at least for the local practice in South East Asia. Since these machines are frequently used interchangeably, the average extraction distance should be limited to 50 m, a scenario in which the differences in performance are the lowest. T1 maintains higher daily production and a greater number of work cycles at longer distances, highlighting the importance of choosing the appropriate tractor size for varying extraction distances in short-rotation eucalyptus forestry. Furthermore, the extraction distance should also be planned based on the performance of upstream and downstream processes, since the local practice makes use of motor-manual tree felling and cross-cutting, manual delimbing and bunching, and medium capacity trucks.

In the past decades, a considerable body of literature has emerged on timber tracking and tracing in the forest and timber industry supply chain. Therefore, a systematic literature review was conducted using an established method (»PRISMA«). To help define the relevance of timber tracking and tracing, this review addresses the subject areas, objectives and characteristics from scientific studies conducted over the past 25 years. In total 213 papers were included in the qualitative synthesis of the subject areas and objectives, with a 160 of those included in the characteristics synthesis to analyse comparable publication contents.

This study demonstrates the rationale behind the research efforts in the field of timber tracking and tracing. The results showed that the main key objectives were to combat illegal logging and trade, provide sustainable forest management, enable tracking and tracing, enhance efficienc, ensure legal compliance, determine the origin of timber and to identify species. The characteristics of the analysis methods used showed that genetic methods, physical chemistry methods, image methods, geomatics, certification, Radio-Frequency Identification (RFID) and smart technologies and software applications were most common. Most research activities were conducted in Asia and Europe. The majority of tracking and tracing methods were found to be highly practical. The application along supply chain dominated because of the high number of publications in genetic methods where a comprehensive application is possible. Furthermore, the forest, harvesting, and manufacturingwere identified as core application areas. Most studies lacked an economic evaluation of the developed solutions, which is a crucial aspect to consider for future successful implementation. The number of tree/wood species involved was notably extensive with a considerable diversity observed across continents. It will be essential that future research incorporates new technologies such as artificial intelligence (AI) that is currently emerging in the field of timber traceability. This can help achieve the identified objectives and address existing and future challenges through the self-learning property of AI.

This study investigated the greenhouse gas (GHG) emissions associated with various mechanisation levels and extraction methods in Mediterranean chestnut (Castanea sativa L.) coppice forests. Located in central Italy, these forests play a significant role in economic as well as ecological terms. This study addressed a critical gap in emissions data for broadleaf forest operations by examining the productivity and environmental impact of four logging systems. These systems integrate semi-mechanised and mechanised felling methods with skidding and forwarding extraction techniques. The results revealed that mechanised felling significantly boosts productivity by 44–66% compared to semi-mechanised felling but generates over three times the GHG emissions per cubic meter of wood. Notably, extraction operations account for the largest share of total emissions, with skidding emitting nearly three times more than forwarding, primarily due to its lower work productivity. Specifically, forwarding in a Cut-to-Length (CTL) system achieved productivity of over double that of skidding and reduced emissions per cubic meter of extracted wood by up to 63%. Key findings suggested that improving work productivity through optimised extraction methods, operator training, and efficient road network layouts can substantially lower emissions. Among the systems tested, CTL forwarding paired with mechanised felling showed the highest productivity and lowest emissions, presenting a promising model for sustainable chestnut coppice management in Mediterranean regions.

In forest operations, economic advantages can be obtained by increasing the distance between the skid trails. This protects soil by reducing the compacted area, while at the same time increasing the productive timber ground area. These advantages are offset by disadvantages, as fully mechanized timber harvesting is not possible and motor-manual felling is required for the areas that cannot be reached by the harvester. This in turn reduces work safety and increases the workload and personnel requirements, possibly leading to higher timber harvesting costs.

To analyze the consequences of an extended skid trail distance, a timber harvest under real conditions was carried out in north-eastern Germany in the fall of 2023. In a 72-year-old Scots pine (Pinus sylvestris, L.) stand with an area of 23.2 ha, 692 m³ of wood was harvested in a thinning operation. Three different timber harvesting methods with extended skid trail distances of approx. 40 m (ES) were investigated and compared to a fully mechanized system with conventional skid trail distances of approx. 20 m (CS) in a time study with a total of 150 recorded hours. Following the harvest, the residual stand damage was also recorded.

The timber harvesting methods with ES had higher timber harvesting costs than the method with CS, although there are major differences between the three semi-mechanized timber harvesting systems: The productivity of the harvester increases as the number of passes by the harvester decreases (from 13.87 to 14.09 to 15.99 m³/PMH15). Looking at the forwarder productivity, it is higher in ES than in CS. Finally, the costs of the harvesting systems ranged between 29.18 €/m³ for CS to 30.40, 32.41, 34.56 €/m³, respectively, for ES. There is no significant difference in the residual stand damage across the methods. The productivity of semi-mechanized timber harvesting methods can be improved if the motor-manual felling is carried out before the harvester is used and if the trees are not winched with a cable tractor.

In some specific yarding situations ground contact needs to be reduced to an absolute minimum. In such cases, a double-hitch system can serve as an alternative to helicopter logging. In the present investigation, a cable yarding operation using double-hitch carriages for selective thinning in intermediate slope was accompanied by a time and motion study to better understand the working steps and resulting productivity of cable yarding in this unconventional situation. The main aims were to develop a model that can be used to estimate the productivity of comparable yarding operations before their implementation, and to quantify the additional effort relative to the use of a cable yarder with a single-hitch carriage. The results indicated an overall productivity of 5.69 m3ob per productive system hour including delays of up to 15 minutes (PSH15), leading to yarding costs of 104.40 € (m3ob)-1 (in addition to costs for installation and felling). Compared to a system with a common single-hitch carriage, the inclusion of a second lateral yarding stage increased time and cost, contributing 13.30 € (m3ob)-1. Key factors affecting productivity were payload size, number of load pieces, and terrain difficulty, while yarding distances had minimal impact. Compared with traditional yarding, double-hitch operations were less productive and more costly, but they can still be considered a suitable alternative to helicopter logging in sensitive areas.

The investigation of the effects of the noise generated by harvesting equipment on the environment is one of the important topics in sustainable forestry. During timber harvesting, not only workers but also wildlife are exposed to the noise generated. Exposure to noise has both direct and indirect effects on humans and wildlife. The negative effects of noise exposure can be observed depending on its intensity and duration. Noise exposure, which has various psychological and physiological effects on humans, also negatively affects plants and animals. In this study, sound measurements of the chainsaw were conducted during thinning operations within the boundaries of the Alara Forest Management Directorate in Alanya, Antalya Province. The measurement area is a Turkish red pine (Pinus brutia Ten.) stand with a canopy density of 60–65%, a slope of 30–35%, and tree diameters ranging from 20 to 35 centimeters. The noise emitted by the chainsaw during production, ranging from approximately 1 meter to 200 meters, has been modeled using a feedforward Artificial Neural Network (FANN) for sound propagation. The measurement data was used 60% for training, 20% for testing, and 20% for validation. Random trees were assigned to noise attenuation effects on the sound according to the stand characteristics of the study area. Thus, it was aimed to create a realistic sound propagation model and estimation maps. The average performance metrics of the model, RMSE and R² values, were calculated as 4.84 and 0.88, respectively. According to the sound propagation model predicted by the FANN as a static model, it is estimated that the distance at which the chainsaw could affect wildlife behavior is 400 meters or less.

Modern forest harvesting machinery generate an abundance of underutilised data in their control systems. The Controller Area Network (CAN) bus data stream offers the opportunity to investigate the operation of the machinery in detail while in real-world harvesting scenarios. This study uses CAN data to assess a component of operator workload in forwarder operations, by introducing a method to interpret forwarder joystick movements. The data was captured in a clearfell logging operation case study in Canterbury, New Zealand. The joystick data was then analysed to determine the time and number of operator input movements per load cycle (»grab«) totalling 418 grabs. This, combined with video analysis, identified independent variables that describe the grab cycle such as time of day, number of logs per grab, log grade, and the activities of »pencilling« (vertical drop of logs in grab to align large ends) and »dropping« (releasing logs from the grab before loading). Factors that significantly affected the operators' time taken to complete the grab and the number of required joystick movements included number of logs, pencilling and dropping. For example, the average load cycle was 18-seconds for four logs, and this increased by 6.1-seconds and 14.4-seconds per grab when pencilling or dropping, respectively. Average total joystick movements were ~108 per grab. This case study demonstrated that CAN bus data can be used to improve our understanding of the operation of harvesting equipment such as forwarders. An example use of the result is to share and compare this with the harvester operator (who crosscuts and sets out the logs for forwarder-collection) as the need for pencilling and dropping is a consequence of misalignment or debris caught in the piles. The method used also presents an opportunity for human factors research, particularly in operator fatigue management and training through the measurement of joystick movements with a genuine possibility of real-time performance feedback.

Accurate assessment of log and stack volumes is essential for predicting product yields and supporting decision-making in the forest industry. Despite the need to understand stack and log measurement metrics, this remains challenging due to new technological trends, complicated measurement methods, significant variation between regions, species, products, sizes, and age classifications, and prevailing misconceptions about measurement units. The main aim of this study was to compare several currently used log and timber stack volume measurement methods. Additionally, volume conversion factors from gross stack volume to net solid wood volume were calculated. To this end, Scots pine (Pinus sylvestris L.) stands were harvested using a John Deere 1170G harvester. The wood was measured using different methods and technology, including opto-electronic log measurements, manual volumetric timber stack measurements, and photo-optical stack measurements for sawmill, pallet, and other industrial partners. Conversion factors were calculated (dividing the solid wood volume under bark by the gross stacked volume over bark, including air spaces) to convert the gross stack volume into a net or solid wood volume under bark, which is an important unit for roundwood purchasing. The log measurement results showed significant differences between the various wood measurement methods across all assortments. In particular, significant differences were observed between harvester and sawmill measurements. Additionally, a comparison between manual sectional stack measurement and truck load scanning at the sawmill revealed significant differences for the medium-density fibreboard (MDF) timber assortment. Conversion factors ranged from 0.50 to 0.66, with a mean of 0.596, lower for LAS 3 m timber and higher for LAK timber. The results will contribute to a better understanding and general harmonisation of different methods for measuring stacks based on a series of studies of Scots pine assortments.

Norway spruce (Picea abies (L.) Karst.) and silver fir (Abies alba Mill.) are both economically and ecologically important coniferous tree species in Europe. Due to climate change, both of them are affected by dieback. This paper examines the quantity, quality, and value of roundwood produced from healthy, severely defoliated (61–99%) and dead Norway spruce and silver fir trees. The study was conducted in four subcompartments located in the Forest Administration Delnice, Management Unit »Milanov vrh«. In total, 81 trees of silver fir (208.77 m3 of gross volume) and 83 trees of Norway spruce (208.43 m3 of gross volume) were measured. Study results showed that the measured gross volume of silver fir was by 8.29% higher than predicted by the harvesting plan, while the measured gross volume of Norway spruce was slightly higher by 0.90%. The determined assortment structure showed a negative correlation between tree crown defoliation degree and the share of highly valuable assortments for both researched species. Healthy trees of silver fir had the highest share of veneer logs, while dead silver fir trees had the highest share of pulpwood. Silver fir dead trees also had the highest share of waste (22.19%), while healthy and severely defoliated trees had 18.69% and 18.47%, respectively. In the case of Norway spruce, healthy trees had the highest share of veneer logs, while dead trees had the highest share of pulp wood. At the same time, the share of waste remains almost the same regardless of the tree crown defoliation degree (from 17.97% for dead trees to 18.17% for healthy trees). Results of the determined assortment structure reflected on the average tree value, which was also negatively impacted by the tree crown defoliation degree. In the case of silver fir, the value of dead trees along DBH classes was 25.6% to 41.6% lower than for healthy trees, while in the case of Norway spruce, the value of dead trees was 22.4% to 36.3% lower than that of healthy trees. The initial hypothesis that average tree value decreases in the order: healthy trees > severely defoliated trees > dead trees was confirmed. To improve harvesting plans, the inclusion of a tree crown defoliation degree as an additional predictor of assortment structure is strongly supported by the results of this study.

In this study, a method of automatically detecting carriageway edges and damaged areas on the surface of forest road wearing courses was tested based on high-density LiDAR data acquired using a handheld mobile laser scanning device. The results were compared with those of current tacheometric methods. Whereas most previous studies have focused on detecting road segments or objects and road centrelines using object-oriented classifications or support vector machine (SVM) algorithms, our research was directed to detect forest carriageway edges and road surface deterioration. Forest roads are designed with a 20-year lifespan before structural failures affect up to 25% of the surface area. We developed an automatic method for detecting damaged areas in the wearing course using GIS tools in ArcGIS Pro. According to the carriageway edges, an overestimation was found between the areas detected automatically and those surveyed tacheometrically, with the automatically detected area being 28% larger. However, it was also found that most of the damage detected was within the tacheometrically surveyed carriageway edges (89%). Agreement between the damage boundary overlaps was relatively low; at 57%, the total damage area detected automatically was 19% larger than that surveyed tacheometrically. The results show that the new automatic process can provide more precise, objective data, as tacheometrical methods can be influenced by the individual approach of a surveyor. Simple and quick detection of damaged areas allows assessing the condition of forest road surfaces and determining repair priorities.

Landslides, which usually occur in mountainous and hilly areas, occur as a result of the soil or rock material forming a slope moving down under the influence of gravity. Forested areas, mostly in mountainous regions, are susceptible to landslides. Forest roads are important infrastructure facilities to protect forest resources and to achieve sustainable management objectives. Forest roads provide many benefits such as facilitating the transportation of wood raw materials, preventing fires and providing access to areas where recreational activities are carried out. However, inappropriately opened forest roads in forest areas cause problems such as landslides, which cause both serious destruction of road networks and serious deformations in forest areas. Landslide-prone forest roads also cause serious economic losses due to disruption of product transport and road maintenance costs. Within the scope of this study, landslide susceptibility maps (LSMs) were produced to determine the relationship between landslides and landslide-causing factors in Handüzü Forest Management Unit of Kastamonu Regional Directorate of Forestry (KRDF) located in the Central Black Sea Region of Türkiye. Land use, altitude, slope, aspect, plan and profile curvature, topographic wetness index (TWI), distance to forest road, drainage networks and fault, crown closure and lithology were used as conditioning factors in the study. Logistic Regression (LR) and Support Vector Machine (SVM) based machine learning models were used to generate LSMs. The receiver operating characteristics (ROC) curve and area under the ROC curve (AUC) method were used to compare the performance of landslide susceptibility models. In the accuracy assessment using the prediction rate curve, the AUC value was 0.968 for the SVM model and 0.668 for the LR model. The AUC values confirmed that SVM performed much better than LR. In addition, the susceptibility of newly planned forest roads (not currently available in the field) in LSMs were determined in the study. As a result of the study, it was determined that the most effective factors affecting landslides in Handüzü Forest Management Directorate are distance to forest roads and drainage networks. In the analyses, it was found that 28.28% of the existing forest roads in the LSM produced with SVM and 56.57% in the LSM produced with LR were found to be in »high« and »very high« landslide susceptible areas. Similarly, 38.43% of the newly planned roads in the LSM produced with SVM and 52.23% in the LSM produced with LR were found to be in »high« and »very high« landslide susceptible areas. These findings showed that forest roads are the main factor in the occurrence of landslides in the study area. Therefore, taking LSMs into account in the planning of forest roads will contribute to reducing the damages that may occur in forest areas due to landslides.

Given the ongoing climate warming that can lead to water scarcity, water retention has been on the forefront of forest ecosystem services. Water harvesting pits on forest roads are one of the possible engineering measures that can help mitigate some of the negative impacts forest roads have on the hydrological regime of the forest ecosystem. The aim of the research is to inform the scientific and professional public about the function and potential of water harvesting pits under forest road culverts and to offer insight into the significance of expected benefits of these objects for water retention and improvement of forest stand hydrological conditions. In this study, standard engineering methods were used to design and build water harvesting pits connected and not connected to culvert mouths and to equip the whole surrounding area with soil moisture and water level sensors. During the two-year study period, a number of irrigation experiments were also performed. The goal was to observe and evaluate the distribution of water from the pits to the surrounding soil and forest stands. Even though water harvesting pits and similar water retention objects on the forest road network seem very beneficial on paper, data from our research does not fully support it. According to our results, the benefits obtained seem much smaller than originally expected to a point that the viability of such measures is probably very low both from the forest stand and water management standpoint. More research is definitely needed in a wider variety of conditions and with a longer time frame.

Fast growing species such as willow have been found to be a viable alternative for bio-energy production. Establishment of willow crops requires a series of operations, among which planting is important for their success. Partly mechanized planting has been studied lately in terms of productivity and costs, and it was found to be a viable alternative for small and dispersed plots. However, no research has addressed its suitability in terms of work intensity. One important assumption is that physical strain would be higher in such operations, mainly due to an intense use of the upper limbs, probably leading to a high cardiovascular workload. This study evaluated the level of physical workload in partly mechanized willow planting operations by heart rate measurements taken on six subjects, which were observed during all the common planting tasks. Close to 65 hours of observations were taken at a rate of one second, and the heart rate increment was used as the main indicator to characterize the workload of planting work. The findings indicate that there was a task-based variability in cardiovascular response (ca. 87 to 96 bpm) and in the heart rate increment among the subjects (ca. 14 to 28%). In addition, there was a differentiation in terms of heart rate increment among the planting tasks. Nevertheless, most of the data indicated a low to moderate cardiovascular workload. Although these results validate partly mechanized planting as a suitable alternative in terms of cardiovascular output, future studies should evaluate other ergonomic conditions such as the biomechanical exposure and the risks of developing musculoskeletal disorders.

In Bosnia and Herzegovina, black alder appears in scattered smaller forest stands, fragments and patches that are still not spatially separated and allocated in management plans, despite its high ecological importance. The objective of this study is to model a black alder ecological niche considering combined effects of climate, hydrological and air quality determinants to support decision-making of conservation and restoration activities on a local/regional level. Black alder occurrence was registered on 72 temporary sample plots representing about 1500 trees in the Bosna River basin corresponding to Level 6, EU-Hydro River Network Database. Six climatic variables (average annual temperature, minimum temperature, maximum temperature, sum of temperature above 5°, sum of precipitation, maximum precipitation), five hydrological variables (average annual flow, minimum flow, maximum flow, flow between 1961–1990 and water level) and five air quality variables (average annual concentration of air particulate matter of PM2.5 and PM10 mm, SO2, NO2, maximum  CO2) were interpolated spatially on 10 m grain size based on hydro-meteorological data from 13 national stations. The MaxEnt method was used to predict spatial distribution model, where predicted occurrence probabilities are classified in habitat suitability classes. The MaxEnt model revealed high-quality spatial prediction (AUC=0.95). The most significant determinants were average annual sum of precipitation and average annual 24-hour maximum  CO2 concentration (cumulative about a 72% contribution). The highest occurrence probabilities were related to areas with less than 1400 mm of annual sum precipitation and elevated CO2 linked to low NO2. The areas with high species occurrence are mainly located in continental Bosnian Internal Dinarides in the valley and partly on hilly and sub-mountainous positions overlapping pedunculated oak-hornbeam and Illyrian sub-mountainous beech forests. Modeled ranges of precipitations and air variables concentrations indicate that black alder prefers continental low hilly and plane positions covering forest edges, although some suitable ecological niches are predicted in sub-urban and peri-urban green areas. The obtained model of species distribution determined spatially ecological niches important for conservation and restoration to maintain ecological services and biodiversity as well as aesthetic and recreational roles of black alder, which are important for local communities.