Compiling the research on forestry ergonomics, which is still a marginal field in terms of the sheer volume of published forestry-related articles, gives a good foundation and guidance for future ...research and publishing. This review aims to compile, classify, and analyze forestry ergonomics publications in JIF (Journal Impact Factor) journals regarding their spatial and temporal distribution, observed operations, machines and tools, and risk factors. A reference period from 2014 to 2023 was observed in this study. The Web of Science Core Collection database was used to filter publications in the field of forestry and ergonomics. A total number of 102 articles were selected. After selection, data regarding publishing year, journal name, main field, country of origin, forest operation, machine/tool, and risk factor were noted. The number of articles is ever-increasing with the last four years having above average numbers of articles. Countries from Europe and South America (Brazil) have the most publications. Most of the journals are ranked in the top 50%. Harvesting, wood extraction, and pre-harvesting operations have the highest number of records. Chainsaw, skidder, and pre-harvesting tools are the most observed means of work. The risk factors with the highest percentage of records are workload (23%), noise (20%), vibration (20%), postural load (16%), and MSD (Musculoskeletal Disorder) occurrence (7%).
The aim of this research is to measure the energy consumption and compare the cutting performance of three types of battery-powered chainsaws (Stihl MSA 200, Stihl MSA 220, and Stihl MSA 300). Tested ...chainsaws were powered by two different battery packs (Stihl AP 300 S and Stihl AP 500 S) with different energy capacity and output current when cutting two wooden beams, European beech (Fagus sylvatica L.) and black locust (Robinia pseudoacacia L.) with different densities and moisture content. Energy consumption was measured using a multimeter built-in battery charger housing, and consumed energy was noted in watt-hours. Each individual cut was recorded with an action camera at 60 frames per second, and the duration of the cuts recorded in centiseconds was observed on the obtained recordings. Results show significant differences in energy consumption and cutting duration between individual chainsaw/battery combinations. Energy consumption ranged from 2.45 to 4.50 Wh per cut for beech (Stihl MSA300E_AP500S and Stihl MSA220_AP300S, respectively) and from 3.10 to 5.00 Wh per cut for black locust (Stihl MSA300M_AP500S and Stihl MSA220_AP500S, respectively). Duration of the cut ranged from 3.48 to 9.24 s per cut for beech (Stihl MSA300M/H_AP500S and Stihl MSA220_AP300S, respectively) and from 3.74 to 9.35 s per cut for the black locust (Stihl MSA300M_AP500S and Stihl MSA220_AP300S, respectively). In general, it can be concluded that more powerful chainsaw/battery combinations (Stihl MSA300_AP500S) consumed less energy per cut and had better cutting performance (shorter cut). In that regard, more powerful chainsaws had greater cutting efficiency, i.e., more cuts on one charge (battery) but shorter cutting time on one charge. The effect of tree species (fresh-sawed beech/air-dried black locust) on energy consumption and cutting performance is absent on the most powerful chainsaw/battery combinations. Today, lithium-ion batteries still have 70 times less energy density than petrol. However, if there is a significant increase in the energy density of the batteries in the coming times, battery chainsaws will most certainly displace petrol chainsaws from use in the future.
The increasing importance of utilizing new technologies, such as GNSS (Global navigation satellite system) devices, total stations, drones, scanners, etc., in forestry has become evident with the ...development of these tools. Combined with precise GNSS devices, UAVs represent an efficient tool that facilitates field measurements and reduces time spent in the field while also providing highly accurate data. To accurately determine the application of spatial data for calculating the longitudinal slope of forest/logging roads in a research project, measurements based on UAVs were conducted and compared with GNSS data. GNSS data were considered the reference values for the studied area, assuming that satellite positions and internet signals were good. An accurate longitudinal slope was necessary to define fuel consumption on forest/logging roads and slopes throughout the project and to verify the calculation method that could be applied for such or similar terrain conditions and overgrowth. The main goal of this research phase was not to study fuel consumption but to obtain an accurate longitudinal profile of forest/skid roads on rocky terrain that is not overgrown or poorly grown. The study put forth two hypotheses, one of which was ultimately confirmed, while the other was refuted. The results show no significant differences when comparing the absolute elevation of the points in the profiles for defining the longitudinal slope of the road using the program for designing forest/skid roads. While applying such a method of data collection to create the main projects for the (re)construction of forest/skid roads, there are significant deviations in earthwork masses. There was a difference of over 22.64% in one of the types of earthwork excavation on the designed forest road, so the method implemented in the research does not give sufficiently accurate results.
Growing demand for forest machines that cost less to operate than current compared to traditional hydraulic and mechanical ones, along with regulatory pressures for lower emissions, is increasing ...manufacturers’ interest in developing electric and hybrid drives. While purely electric drives of forest machines meet a lot of bottlenecks (costs of the electric components, battery durability, duration of charging, access to the electrical grid, size of batteries that can ensure enough energy for 8 h working time), electric hybrid drives offer a favorable solution for the propulsion of forestry machinery in terms of lower fuel consumption and improved efficiency. Among all forest vehicles, specialized forest tractors (skidders), so far, have not been considered for forest vehicles with hybrid drive capabilities. A skidder is a forest-articulated self-propelled vehicle for pulling trees or parts of trees. In most countries in southern Europe, the use of skidders equipped with forest winches is the most common technique for timber extraction. The first goal of the research is to develop methods for measuring the energy consumption of skidders at different operating tasks and under different field conditions. Research was performed on the skidder Ecotrac 140V (from Croatian producer Hittner Ltd.) during timber extraction in mountainous terrains in Lika–Senj County. The skidder was equipped with a measuring device WIGO-E (Telematic Data collector) gateway with an integrated GPS system, which ensured data were collected from sensors and motor and stored in a computer via CANBUS and data transfer with GSM to Web platforms. Additionally, a fuel-flow meter was installed on the skidder. Data on fuel consumption (mL), position (traveling route), detection of winch work, engine rpm (min−1), engine torque (% of max), throttle position (%), and engine temperature were measured with a sampling frequency of 5 s. Furthermore, skidder load volumes per cycles and slopes of tractor paths were constantly measured. The paper shows the skidder’s energy consumption per day, work cycle, and individual work procedure with regard to the size of the load, the slope of the tractor path, and the direction of movement based on overlapping and merging all measurement data. Using mathematical and simulation models of the drive with defined operating cycles obtained by measurement, the possibilities of the hybrid drive and the dimensions of the elements of the hybrid drive (internal combustion engine, electric motor, batteries, control unit) were determined and are presented in this paper.
During forest harvesting operations, exhaust emissions from forest vehicles are released at different levels depending on several variables. This pollution released into the atmosphere is considered ...one of the main anthropogenic factors that negatively affect forest ecosystems. In this study, we analyzed exhaust emissions from a skidder diesel engine during various engine loads. Measurements were done on an ECOTRAC 140 V skidder with the water-cooling diesel engine and a built-in catalyst with an SCR system. The composition and amount of exhaust gases (CO, CO2, O2, NOx,) at different loads of the diesel engine of the skidder and engine temperature were measured using a MAHA MET 6.3 measuring device. The amount of exhaust gases was analyzed in relation to the engine speeds, engine temperatures, and the European emission standards for engines used in nonroad mobile machinery (NRMM). Influences of catalyst systems and recommendations for more environmentally friendly forest harvesting practices are addressed. With the engine unloaded, the amount of CO2 increased when engine speed was increased, while other amounts of exhaust gas decreased. During the cold start, the concentrations of hydrocarbons and nitrogen compounds were high. The composition of the exhaust gas was affected by the exhaust reduction system installed in the tractor and the amount of the exhaust gas was dependent on the engine load. The skidder engine met the requirements of the exhaust gas standards EPA/COM IIIB Tier 4 (I) under which it is declared. With a load engine during winch operation (2300 rpm), NOx amounts mostly exceed the limit values of the standard. Exhaust emissions can be reduced at various operating levels by utilizing the most environmentally friendly technologies and following the correct procedures, such as warming the engine up to operating temperature prior to operation and operating in the most favorable mode with optimal speed. The regular reduction of exhaust limit values to newer stages of the standard therefore leads to the continuous development of engines and forest vehicles in general.
Background and Purpose: Fuel consumption in timber harvesting operations is significant for both economic and environmental reasons. In economic sense, one significant part of timber harvesting costs ...is reduced to fuel costs, and in environmental sense 80% to 95% of exhaust emissions and soot particles in forest machinery are in fact associated with fuel consumption.
Materials and Methods: The research object was a 6-wheel Valmet 840.2 forwarder and research was conducted in Forest Administration Vinkovci (lowland part of Croatia) during seeding felling in a stand of pedunculate oak and narrow-leafed ash. For the purpose of measuring fuel consumption on the researched forwarder a differential flow device was installed together with FMS (Fleet Management System) which was used for data transfer.
Results: Fuel consumption is expressed in six different ways concerning: cycle, extraction distance of 100 m, time (hour), load mass (tons), gross load volume (m3) and product of mass and transporting distance (tkm). Fuel consumption amounted to 0.56 l·tkm-1 during the extracting of logs and 0.78 l·tkm-1 during the extraction of energy wood. The results also show an increasing trend of fuel consumption expressed per ton of transported load with the increase of travelled distance during the extraction.
Conclusions: Fuel consumption expressed in l·tkm-1 is the most accurate fuel consumption indicator because it allows a realistic comparison of different types of machines with different loads (t, m3) at different extracting distances. The higher fuel consumption of an unloaded forwarder compared to a loaded forwarder can be explained with an increased wheel slip of an unloaded forwarder due to reduced traction between wheels and the soil both in the extraction of logs and energy wood.
Background and Purpose: The relevance and importance of forestry entrepreneurship is constantly increasing, especially in countries with high transition dynamics in forestry sector. In Croatia, ...forestry entrepreneurs have in short time become an indispensable part in the performing of harvesting and other types of forestry operations. This paper presents the current status and perspectives of forestry entrepreneurship in Croatia.
Materials and Methods: Based on the analysis of the available data from various sources (normative state acts, Forestry Chamber’s official registries, databases and documents, state forestry company business reports etc.), this paper provides an overview of the legal and institutional framework for the activities of private entrepreneurs in Croatian forestry with particular attention to licensing forestry contractors and the role of the Croatian Chamber of Forest and Wood Technology Engineers (Forestry Chamber).
Results and Conclusions: The paper explains the activities, tasks, organization structure and formal bodies of the Forestry Chamber. The licensing model is also presented together with the formal criteria and minimum conditions which forestry entrepreneurs have to fulfill in order to acquire a license for forest work operations. Structural characteristics and the profile of forestry entrepreneurs is given by the number, size and type of business, the type of forest operations for which they are licensed, and the volume of work that they are performing for Croatian Forests Ltd, the state forest company. Finally, the paper includes some reflections on the perspectives and possibilities for improving the status of entrepreneurship in Croatian forestry.
Background and Purpose: The existing public and forest transport infrastructure (truck forest roads) are permanent objects used when passing through forests. They also serve as a firefighter belt and ...provide direct access to firefighting vehicles, or are used as the starting point where firefighting teams extinguish fires or move toward remote fires. The paper identifies the existing fire road network (including public roads, forest roads, non-classified roads and fire roads) for access of firefighting vehicles during fire extinguishing interventions.
Material and Methods: An analysis of the intervention rate was conducted on a dispersive sample (35 positions) from two volunteer fire associations (VFA) on the island of Vis. Also, an analysis of the surface availability to fire vehicles concerning the time of departure from the fire station was conducted, as well as the comparison with the Standard time of intervention defined by the regulations on fire department organization in the Republic of Croatia.
Results: For each simulated fire location for intervention of two existing volunteer fire associations: VFA Komiža and VFA Vis, results show that for a few fire locations, despite a smaller distance from the VFA Komiža, a quicker intervention is possible from the VFA Vis (locations 4, 5 and 14), and vice versa (locations 21, 22 and 25). With the use of a New Service Area, tool intervention times regarding different areas were calculated. Intervention times were divided into intervals: <5 min, 5–10 min, 10–15 min, 15–25 min and >25 min. The last two categories of area are beyond reach for firefighters within the Standard time of intervention (15 min) and together they comprise to 27.88% of the total research area.
Conclusions: The results of Closest Facility tool indicate that for the simulated fire position the best/fastest route is not always the shortest one, because of a significant effect of the structural elements of each road, the state of the road and the longitudinal slope of the road itself. One of the possible approaches to gain access to the area for fire-fighting, as well as to prioritize fire roads regarding maintenance/reconstruction is to improve road conditions, and thus increase the average driving speed.
U radu se prikazuje proces proizvodnje toplinske i električne energije u kogeneracijskom postrojenju te proces proizvodnje drvnih peleta. Cilj je ovoga rada analizirati dobit energije (EROI) od ...energenata koji nastaju kao proizvod sadržan u toplinskoj i električnoj energiji te energiji koja je sadržana u drvnim peletima. Prema dobivenim rezultatima proizvodnja samo električne energije iz drvne biomase u kogeneracijskom postrojenju nije isplativa s energijske točke gledišta jer je dobivena električna energija tek 1,43 puta veća od uložene energije drva (EROIel = 1,43 : 1). Dobivena je toplinska energija 4,38 puta veća od uložene energije drva (EROItopl = 4,38 : 1), dok je dobivena energija kod proizvedenih drvnih peleta 4,81 puta veća od uložene energije drva (EROIpel = 4,81 : 1). Takav dobitak energije u proizvodnji toplinske energije u kogeneracijskom postrojenju i drvnih peleta energijski je isplativ, ali je višestruko nepovoljniji u odnosu na upotrebu drvne sječke, a posebice u odnosu na upotrebu kratko cijepanoga drva u kotlovima za dobivanje samo toplinske energije. Drvo je obnovljiv izvor energije i njegovom ekonomičnom upotrebom može se stvoriti značajan energijski dobitak, ali zbog trenda upotrebe obnovljivih izvora energije i sve veće potrebe za električnom energijom takav je način dobivanja električne energije financijski isplativ, iako on nije opravdan s gledišta energijske isplativosti.
The paper presents the process of heat and electricity production in a cogeneration plant and the process of wood pellet production. The aim of this work is to analyze the energy gain – EROI for energy products generated as a product contained in thermal and electrical energy and the energy contained in wood pellets. According to the obtained results, the production of only electrical energy from wood biomass in a cogeneration plant is not profitable from an energy point of view, since the obtained electrical energy is only 1.43 times higher than the input wood energy (EROIel = 1.43 : 1). The obtained thermal energy is 4.38 times higher than the input energy of wood (EROItopl = 4.38 : 1), while the energy obtained from the produced wood pellets is 4.81 times higher than the input energy of wood (EROIpel = 4.81 : 1). Such an energy gain in the production of thermal energy in a cogeneration plant and production of wood pellets is energetically profitable, but it is many times less favorable compared to the use of wood chips, and especially compared to the use of short-cut wood in boilers to obtain only thermal energy. Wood is a renewable source of energy and its economic use can create a significant energy gain, but due to the trend of using renewable energy sources and the increasing need for electricity, such a way of obtaining electricity is financially profitable, although it is not justified from the point of view of energy profitability.
Planning is an intellectually demanding process that requires a conscious
determination of actions and decisions based on related purpose, knowledge
and right decisions. During planning timber ...harvesting it is very important
to choose the best possible technology for timber extraction. The use of
multi-criteria-decision-making models is a very good way of dealing with
various forestry issues especially in terms of choosing the best applicable
technology for timber extraction. Modern forest management in the Republic
of Croatia in terms of timber harvesting mostly relies on ground based
wheeled systems. The goal of this research is to show how the current way of
planning timber harvesting (timber extraction) and accordingly the
construction of secondary forest road network affects future planning and
introduction of ?new? technologies for timber extraction i.e. forest
cableway. Analysis of suitable forest stands for different timber extraction
technologies s was carried out in the management unit Garjevica-Cazma with an
area of 4380.20 ha. The paper presents multi-criteria-decision-making model
for defining terrain suitable for ground based wheeled systems (skidder with
a winch and forwarder) and forest cableway on the base of raster maps (grid
of 20?20 m i.e. 0.04 ha). The criteria used to select different technologies
for timber extraction were: terrain slope, distance from the forest road,
distance from the skid road and harvesting density. Analysis using GIS tools
in ArcGIS and Idrisi applications goes in two directions, first the analysis
of suitability of using selected technologies for timber extraction using
four criteria, and comparison with results of the analysis where the
criterion ?distance from the skid road? has been excluded.
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