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The article presents the results of measurements regarding the impact of the MHT9002HV tracked harvester on surface deformations and changing the physical parameters of the soil of three operational trails. The measurements were made in the terrain with a longitudinal slope of up to 14.9° (33.2%) and a transverse slope of up to 8.8° (17.9%). Spruce deadwood trees in mountain forest habitats were harvested. Static Eijkelkamp Penetrologger 0615SA and dynamic own design penetrometer were used to measure penetration resistance, soil samples were taken to determine bulk density, moisture content, and ground deformations on the trails were measured with a laser profilometer. A statistically significant increase in soil penetration resistance measured with penetrometers occurred for trails in the left rut at a depth of 16–20 cm. The change in the bulk density and moisture content proved statistically insignificant. The maximum ground deformation on the trails reached an average of 5.9 cm. The selection of a machine with low unit pressures (33 kPa), under the given favorable atmospheric conditions (there was a high temperature reaching 35 °C), with low soil moisture, protective organic layer of high thickness, and post-limbing residues, was optimal. The comparison of the results of the compactness measurements made with different penetrometers shows that the values obtained for the static penetrometer 0615SA are lower than those of the dynamic penetrometer of our own design. This is due to the lack of registration of high compactness in the memory of the 0615SA device. In the case of the impact penetrometer measurement, this problem does not occur, however, the presented solution does not allow performing a large number of measurements, and data processing in the case of such a simple solution is tedious. There is a need to develop a new penetrometer useful for determining soil compaction under similar difficult measurement conditions.

The accurate estimation of bark thickness is important for foresters for several reasons. It is crucial for timber volume estimation and can help improve the quality of forestry records, and bark has a growing commercial importance as a high-value bioresource. The problem is that models such as the Czech Cubic Tables (CCT) polynomial model are frequently unique. Furthermore, the official method requires rounding down the midspan over-bark diameter (DOB) to the nearest centimetre to estimate the double bark thickness (DBT) and merchantable timber volume. Therefore, we verified the significance of the effects of rounding down the midspan DOB on DBT using a dataset of 438 recently harvested Norway spruce (Picea abies L. Karst.) logs from the Central Bohemian region. The correlation analysis showed that for measured data without rounding down the diameters, the variability of the DBT was able to explain only 8% of the DOB variability. As for the rounded-down data, the coefficient of determination was slightly higher, reaching 9%. The paired-samples T-tests showed a significant difference between the DBT as calculated directly from measured data and that from the rounded-down over-bark diameters (p < 0.05). The polynomial and linear models underestimated the DBT (2.24 and 1.75 mm on average, respectively) on measured data. In contrast, for data from the rounded-down DOB, the models overestimated the DBT (2.70 or 3.18 mm on average, respectively).

Our research aimed to quantify stress load in drivers by monitoring the load on the radial extensor carpi radialis (musculus extensor carpi radialis) on different types of forest and other categories of roads. We observed changes in the electrical potential of skeletal muscles using electromyographic measurements and changes in heart rate using a Biofeedback2000 x-pert recorder. We measured the loading of drivers during the normal operation of timber trucks and timber trucks with trailers, while the reference measurements took place in a passenger car. We obtained descriptive statistics from the individual measurements and evaluated the normality of the measured data. Differences in muscle load increased when driving on lower-grade roads. The muscle load increased significantly, especially when passing through villages, inversely proportional to the width of the roads and the radius of their bends. Experiments revealed that the drivers of loaded vehicles who drove on lower-grade roads were under higher stress. Muscle load of drivers a loaded timber truck with a trailer was more difficult on roads of lower grades than on roads of grade I by 41.3%. Driving a timber truck is 21.9% more difficult on lower grade roads than on grade I roads. For preventive health and safety reasons, it is optimal to alternate trucking with a different type of work, thus minimizing the chance of occurrence of health disabilities.

Innovations are a key component of the forest bioeconomy. Many types of innovations are needed for an efficient forest bioeconomy to be deployed. This article aimed to analyze the scientific literature on the topic of innovations in the forest bioeconomy, to understand where we are and where we are likely to be in the future, considering technologies, business models, etc. First, the scientific literature, in the form of peer-reviewed articles indexed in the Web of Science, was compiled in a comprehensive dataset, on which we analyzed the most important authors, their affiliations, regions they come from, journals where papers were most commonly published, and under which categories the papers were indexed. The total number of papers matching the keywords was 161. We found that the number of papers published on the topic is increasing and that, on average, each paper was cited 18 times. A total of 504 authors dealt with the topic, presenting a rather small community. This finding was reinforced by the outcomes of the analysis of regions where the authors of the papers were affiliated—Europe being the region to which most papers were affiliated. We conducted a qualitative synthesis of the literature on forest bioeconomy innovations. We found that authors dealt with the necessary adaptation of policies, while innovations were mainly focused on biorefining, biotechnology, production of various biomaterials, as well as innovations of business models and stakeholder interactions.

Cut-to-length (CTL) operations are expanding in Central European bio-economies. However, they are costly, so efficiency must be maximized. The objective of this study was to analyze direct operational costs of three forwarders from the year 2006 until 2019. Annual amortization, services, materials, and personnel costs were analyzed and compared through ANOVA, trends were analyzed through linear regression. Forwarders LVS 5, John Deere 1010, and John Deere 1110E were deployed in coniferous forest stands with a mean stem volume between 0.10 and 0.84 m3/stem, forwarding distance between 261 and 560 m. The machines forwarded between 4045 and 34,604 m3 of timber per year, over operational times between 490 and 3896 MH (machine hours)/year, reaching machine utilization between 58% and 89%, machine productivity between 3.5 and 12.3 m3/MH, and costs between 20.95 and 84.39 €/MH. The most substantial were personnel costs (35 to 66% of the total costs), followed by materials (14.9–27.1%), amortization (12.5–15.7%), and services (3.3–22.1%). Differences between total operational costs per m3 of machines with different engine powers were not observed.

Research Highlights: In this study, we present the use of time-lapse photos as a way to estimate the height of the load on the forwarders. This approach, using nonprofessional outdoor cameras, is a cheap and time-effective solution for continuous load height measurements, and it offers at least the same accuracy as a gauge measurement. This method represents another approach to the automation of time studies in forestry. Background and Objectives: Time studies require information about the load on the forwarders. Until now, this information was obtained either by using a gauge measure, sampling of the load, or averaging the load from large area datasets. More accurate methods like laser scanning are costly and fragile. During time study preparations, we suggested a robust system of measuring the load height and tested it against the commonly used gauge measuring technique. Materials and Methods: Two cameras took pictures of the load; these photos were processed for camera lens distortion and rectified into the cartesian coordinate system, and the height of the load was calculated. These values were then tested against gauge measured values using paired t-test. Results: Straight line distance calculated from the images and the gauge-measured distance did not show a significant difference (p-value 0.9354). Calculated vertical distance was, however, significantly different from the calculated straight-line distance (p-value of 0.0015), suggesting possible bias of the gauge measured distance. The root mean square error (RMSE) of the rectification process was, on average, 0.42 cm. Conclusions: The proposed method was verified to correspond with the gauge measure method; however, our research raised the question of the gauge method reliability, as the taken measurements are not perfectly vertical, and for the correct load estimation, the vertical distance is needed. We, therefore, conclude that for this photogrammetry method, the vertical, rather than straight-line, distance should be used. The presented solution can be used for long-term data collection without interrupting the whole forwarding process for taking the load measurement. The longer data processing in office enables researchers to spend less time in the field taking hand measurements.

Harvesters produce one third of timber in Czechia. The aim of this study was to analyze the over- and under-bark volume estimates of Scots pine (Pinus sylvestris L.) timber produced by a mid-performance harvester. The data were collected between March 2017 and June 2018. In total, 4661 stems cut into 29,834 logs were analyzed. For volume estimation, StanForD offers several price categories using various algorithms. Three of these price categories are relevant for Czech forestry—M3s, M3toDE, and M3miDE. The M3s price category is based on the estimation of partial volumes of 10 cm long sections, which are summed. Therefore, this price category represents the volume estimation closest to the true volume. By comparison, the M3toDE and M3miDE price categories use the same algorithm for volume estimation, which is based on the Huber formula using a midspan diameter rounded down to the nearest whole centimeter. The M3toDE price category underestimated the over-bark volume by 6.48% compared to the reference price category M3s. The mean log volume estimated through the M3s price category was significantly higher than the M3toDE volume both in individual grades and without grading. We found significant differences between under-bark volume estimates by the diameter band bark deduction method (DBM) and the parametric linear bark deduction method (PLM) used in harvester’s systems according to the Guidelines for Electronic Scaling of Timber for Harvesters in Czechia (GEH) for Scots pine butt logs with rough bark, and also for other logs with normal bark thickness. To obtain under-bark volume estimates of Scots pine timber that are comparable with the Guidelines for Timber Scaling in Czechia (GTS) using the parametric nonlinear bark deduction method (PNM), we recommend using the algorithm of the M3toDE price category, with double bark thickness determined by the diameter band bark deduction method.

Timber is the most important source of revenue in forestry and, therefore, is necessary to precisely estimate its volume. The share of timber volume produced by harvesters is annually growing in many European countries. Suitable settings of harvesters will allow us to achieve the most accurate volume estimates of the produced timber. In this study, we compared the different methods of log volume estimation applied by control and information systems of harvesters. The aim was to analyze the price categories that can be set up in the StanForD standard and to determine the differences between the algorithms used for log volume estimations. We obtained the data from *.STM files collected from March 2017 until June 2018 on a medium-size harvester. We analyzed price categories and found seven different algorithms used to estimate the log volumes. Log volume estimates according to Algorithm A2 were considered as standard because these estimates should be closest to the true log volumes. Significant differences, except the difference between Algorithm A2 and Algorithm A3, were found between log volumes estimated by different algorithms. After categorization of logs to assortments, the results showed that significant differences existed between algorithms in each assortment. In the roundwood assortment, which contains the most valuable logs, a difference of more than 6% was found between the log volumes estimated by Algorithm A5 and Algorithm A2. This is interesting because Algorithm A5 is widely used in some Central European countries. To obtain volumes closest to the true volumes, we should use Algorithm A2 for the harvester production outputs. The resulting differences between the algorithms can be used to estimate the volume difference between harvester outputs using the different price categories. Understanding this setting of harvesters and the differences between the price categories will provide users useful information in applied forest management.