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Functional connectivity, the extent to which a landscape facilitates or impedes the dispersal of individuals across the landscape, is a key factor for the survival of species. Anthropogenic activities, such as urbanization, agriculture and roads, negatively impact functional connectivity of most species, particularly low‐vagility species like lizards. Here, we examine how a landscape modified by anthropogenic activities affects the functional connectivity, at both broad and fine scales, of a widely distributed generalist lizard Sceloporus grammicus in the eastern Trans‐Mexican Volcanic Belt, Mexico. We estimated for the first time the species' genetic structure, gene flow and functional connectivity in agricultural and forest zones using genomic data, a comprehensive landscape characterization and novel methods including gravity models. Our results showed not only marked genetic differentiation across the study region but also that functional connectivity is maintained for tens of kilometres despite S. grammicus low vagility. Specifically, we found that substrate and air temperature facilitated connectivity over broad and fine scales, respectively, while agricultural cover, relative humidity and slope were important for connectivity and gene flow. Contrastingly, forest cover and roads favoured (broad‐scale) and limited (fine‐scale) connectivity, likely associated with movement facilitated by small forest patches and with thermoregulation. Altogether, these results support that S. grammicus alternates its thermoregulatory behaviour depending on the distance travelled and the habitat environmental conditions, and that it can disperse through relatively modified landscapes, mainly using agricultural zones. The information obtained is crucial to understanding the response of lizards to current anthropogenic pressures and their potential to adapt. [ABSTRACT FROM AUTHOR]

The intensive use, development, and expansion of the road network is expanding the zones of direct impact of road transport on forest ecosystems. Issues related to the mobility of trace elements in forest ecosystems along motorways are very important due to the numerous environmental risks associated with the excessive accumulation of metals, the ability to migrate and accumulate in plants and animals, and the risk of transferring these elements to higher trophic levels. The aim of this article was therefore to determine the impact of road traffic on the basis of contents of trace metals Cd, Cr, Cu, Ni, Pb, and Zn and to describe the relationship of these contents in moss gametophytes and blueberry leaves taken in the vicinity of an existing and variously expanded expressway (S7, Poland, Europe). Analyses of transport impacts included the effects of distance and time of pollutant deposition and road transport on habitat and stand conditions. The highest contents of Cd, Cr, Cu, Ni, Pb, and Zn in moss tissues were found in fir stands and the contents were, respectively, 0.36 mg·kg−1, 5.91 mg·kg−1, 12.5 mg·kg−1, 3.26 mg·kg−1, 8.82 mg·kg−1, and 55.28 mg·kg−1. Mosses showed the best bioindication capacity of all of the studied ecosystem elements. The Pb, Zn, Cr, Cu, and Ni contents were particularly markedly elevated in moss tissues relative to non-anthropopressured areas and dependent on distance from the emitter (road). Blueberry proved to be a less useful bioindicator, as the contents of Cd, Cr, Cu, Ni, Pb, and Zn found were similar to the data from non-anthropopressured areas and were, respectively, 0.09 mg·kg−1, 0.98 mg·kg−1, 7.12 mg·kg−1, 2.49 mg·kg−1, 1.18 mg·kg−1, and 15.91 mg·kg−1 in fir stands and 0.04 mg·kg−1, 0.47 mg·kg−1, 6.63 mg·kg−1, 1.65 mg·kg−1, 0.72 mg·kg−1, and 17.44 mg·kg−1 in pine stands. [ABSTRACT FROM AUTHOR]

In order to improve driving safety and comfort of drivers on curved roads in forest areas, a driving simulation test was adopted to evaluate the driving comfort on curved roads in forest areas from a dynamic perspective using eye movement and heart rate as evaluation indexes. Based on the theory of spatial sight distance, five different spatial visual distance scenarios of curved roads in forest areas were established, and the results showed that the rate of change of pupil diameter and the growth rate of heart rate of the driver decreased with the increase of spatial sight distance, and the driving comfort increased continuously. The minimum spatial sight distance values considering the pupil diameter change rate and heart rate growth rate were 101 m and 89 m, and the appropriate spatial sight distance values considering the pupil diameter change rate and heart rate growth rate were 128 m and 132 m. [ABSTRACT FROM AUTHOR]

Firstly, Landslide Susceptibility Maps of the study area were produced using Frequency Ratio and Modified Information Value models. Nine factors were defined and the Landslide Inventory Map was used to produce these maps. In the Landslide Susceptibility Maps obtained from the Frequency Ratio and Modified Information Value models, the total percentages of high and very high-risk areas were calculated as 10% and 15%, respectively. To determine the accuracy of the produced Landslide Susceptibility Maps, the success and the prediction rates were calculated using the receiver operating curve. The success rates of the Frequency Ratio and Modified Information Value models were 82.1% and 83.4%, respectively, and the prediction rates were 79.7% and 80.9%. In the second part of the study, the risk situations of 125 km of forest roads were examined on the map obtained by combining the Landslide Susceptibility Maps. As a result of these investigations, it was found that 4.28% (5.4 km) of the forest roads are in very high areas and 4.27% (5.3 km) in areas with high landslide risk areas. In the last part of the study, as an alternative to forest roads with high and very high landslide risk, 9 new forest road routes with a total length of 5.77 km were produced by performing costpath analysis in with geographic information systems. [ABSTRACT FROM AUTHOR]

This paper presents the results of comparative studies of strain modulus from static (PLT) and dynamic (LWD) plate testing. The tests were conducted on 9 sections of forest roads with different surfaces made of unbound aggregates. They produced 140 - element sets of results, including values of reloading modulus (E2) and dynamic modulus of deformation determined using 10 and 15 kg drop weights (Evd10 and Evd15). An attempt was made to determine the relationship between the values of the moduli from tests with LWD loads (10 or 15 kg) and PLT, which would allow to determine the values of reloading modulus based on the dynamic modulus values. The analysis of the test results revealed that the values of the dynamic moduli are characterized by lower variability than those obtained from static testing and that from the engineering point of view there is no significant relationship between the sets of results of the subgrade deformability tests made with dynamic and static plates. The analysis of the results confirmed a simple relationship that allows for a qualitative assessment of subgrade deformability defined by the values of reloading modulus PLT tests based on the results of LWD tests with a 10 kg drop weight. The assessment error did not exceed 7% in this case. An analogous relationship was revealed for the results of LWD tests with a 15 kg drop weight. In this case, the assessment error did not exceed 6%. The results of the LWD tests can be used to provide a qualitative assessment of the deformability of subgrade, but the PLT tests are required for its quantitative assessment. [ABSTRACT FROM AUTHOR]

This paper presents the results of comparative studies of strain modulus from static (PLT) and dynamic (LWD) plate testing. The tests were conducted on 9 sections of forest roads with different surfaces made of unbound aggregates. They produced 140-element sets of results, including values of reloading modulus (E2) and dynamic modulus of deformation determined using 10 and 15 kg drop weights (Evd10 and Evd15). An attempt was made to determine the relationship between the values of the moduli from tests with LWD loads (10 or 15 kg) and PLT, which would allow to determine the values of reloading modulus based on the dynamic modulus values. The analysis of the test results revealed that the values of the dynamic moduli are characterized by lower variability than those obtained from static testing and that from the engineering point of view there is no significant relationship between the sets of results of the subgrade deformability tests made with dynamic and static plates. The analysis of the results confirmed a simple relationship that allows for a qualitative assessment of subgrade deformability defined by the values of reloading modulus PLT tests based on the results of LWD tests with a 10 kg drop weight. The assessment error did not exceed 7% in this case. An analogous relationship was revealed for the results of LWD tests with a 15 kg drop weight. In this case, the assessment error did not exceed 6%. The results of the LWD tests can be used to provide a qualitative assessment of the deformability of subgrade, but the PLT tests are required for its quantitative assessment.

Identifying the relationship between forest roads and wildfires in forest ecosystems is a crucial priority to integrate suppression and prevention within wildfire management. In various investigations, the interaction of these elements has been studied by using road density as one of the anthropogenic dependent variables. This study focused on the use of a broader set of metrics associated with forest road networks, such as road density, the number of links (edges), and access percentage based on two effect zones (road buffers of 75 m and 97 m). These metrics were employed as response variables to assess forest road network suitability in relation to wildfires, specifically the number and size of fires (2000–2021), using the Apulia region (Italy) as a case study. In addition, to enhance the comprehensive understanding of road networks in forest ecosystems in relation to wildfires, this study considered various affecting factors, including land-cover data (forest, maquis, natural grassland), geomorphology (slope, aspect), vegetation (Normalized Difference Vegetation Index (NDVI)), and morphometric indexes (Topographic Position Index (TPI), Terrain Ruggedness Index (TRI), Topographic Wetness Index (TWI)). We used geographically weighted regression (GWR) and ordinary least squares (OLS) to analyze the interaction between forest road metrics and dependent variables. Results showed that the GWR models outperformed the OLS models in term of statistical results such as R2 and the Akaike Information Criterion (AICc). We found that among road metrics, road density and number of links do not effectively demonstrate the correlation between roads and wildfires as a singular criterion. However, they prove to be a beneficial supplementary variable when considered alongside access percentage, particularly within the 75-m buffer zone. Our findings are used to discuss implications for forest road network planning in a broader wildfire management analysis. Our findings demonstrate that forest roads are not one-dimensional and static infrastructure; rather, they are a multi-dimensional and dynamic structure. Hence, they need to be analyzed from various perspectives, including accessibility and ecological approaches, in order to obtain an integrated understating of their interaction with wildfire. [ABSTRACT FROM AUTHOR]

Forest road planning incorporates crucial strategies essential for sustainable timber extraction, minimizing environmental impacts and ensuring safe access to forest regions. This paper presents a literature review conducted to examine publications related to forest roads to ultimately filter and evaluate the information on the incorporation of classification systems in the planning strategies for forest roads. Using the Scopus database to gather publications, various data points were mapped, such as temporal distribution of publications, citation metrics, keyword inputs and other bibliometric markers. Through the bibliometric visualization software VOSviewer 1.6.19, this study determined that over the years, the forest road research subject has gained increasing attention with different shifts in focus. However, upon investigating the application of systems of classification implemented on forest road networks, it became evident that this approach is not a recent innovation and there is scarce documentation and development regarding this planning strategy. The information collected also reveals that this type of classification can be found more in technical documents, like design manuals. This outcome suggests that the subject under study is not relevantly covered in forest-related journals, but rather by institutions aiming to identify region-specific needs and develop corresponding systems accordingly. [ABSTRACT FROM AUTHOR]

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was aimed to estimate the economic value of timber products from the forest stands that are potentially saved from wildfires after improving road standards. The study was implemented in the Alanya Forest Enterprise Directorate (FED) in the Mediterranean city of Antalya, Turkey. In the solution process, the possible increase in the accessible forest areas with improved forest road standards was investigated by using GIS-based network analysis methods. In the next step, the timber production in the forest areas potentially saved from the wildfire was calculated based on parameters such as site index, rotation period, and stand structure. Then, the economic value of timber product types was calculated using market prices. The results indicated that increasing the design speed on improved forest roads reduced the arrival time of firefighting teams to the forests, which consequently increased the accessible forest areas within the critical response time. It was found that the accessible forest areas within the critical response time increased from 47,231 hectares to 59,354 hectares when standards of the forest roads were improved. This saved 12,123 hectares of additional forest area from the wildfire in the Alanya FED. The cost of road improvement activities was estimated at US$ 2,286,998. It was calculated that the total timber products obtained from the forest area potentially saved was about 94,721 m3, and worth US$7,545,579 at market prices. The results can be used by policymakers in determining the potential investments in improving forest road standards to enhance the efficiency of firefighting activities. [ABSTRACT FROM AUTHOR]

Delivery performance in wood supply chains is affected by carrying capacity on forest roads. Stochastic weather variations affect carrying capacity of roads and accessibility of harvested wood on landings. In Sweden, annual harvest scheduling is usually based on four seasons and road accessibility classes are set to match these seasons. In reality, road accessibility changes depend on weather variations not season. This causes a risk of poor delivery performance. Delivery performance is evaluated using two performance indicators, backorders (orders not delivered on time) and lead time (time from harvesting to delivery to mill). A data-analytic framework, combining optimization and simulation, is proposed to assess and evaluate these performance indicators for the wood supply chain under stochastic weather variations. An optimization model is used to generate a feasible harvest schedule for expected weather. This is thereafter evaluated given various weather scenarios using a discrete-event simulation model. The combination of optimization and discrete-event simulation is used to assess delivery performance over time, and changes in road accessibility caused by weather variation. An expected decrease in road accessibility implies a stable delivery performance, while an unexpected decrease causes a reduced delivery performance. [ABSTRACT FROM AUTHOR]

Sustainable forest management systems require operational measures to preserve the functional design of forest roads. Frequent road data collection and analysis are essential to support target-oriented and efficient maintenance planning and operations. This study demonstrates an automated solution for monitoring forest road surface deterioration using consumer-grade optical sensors. A YOLOv5 model with StrongSORT tracking was adapted and trained to detect and track potholes in the videos captured by vehicle-mounted cameras. For model training, datasets recorded in diverse geographical regions under different weather conditions were used. The model shows a detection and tracking performance of up to a precision and recall level of 0.79 and 0.58, respectively, with 0.70 mean average precision at an intersection over union (IoU) of at least 0.5. We applied the trained model to a forest road in southern Norway, recorded with a Global Navigation Satellite System (GNSS)−fitted dashcam. GNSS-delivered geographical coordinates at 10 Hz rate were used to geolocate the detected potholes. The geolocation performance over this exemple road stretch of 1 km exhibited a root mean square deviation of about 9.7 m compared to OpenStreetMap. Finally, an exemple road deterioration map was compiled, which can be used for scheduling road maintenance operations. [ABSTRACT FROM AUTHOR]

Forest road maps are a fundamental source of information for the sustainable management, protection, and public utilization of forests. However, the precision of these maps is crucial to their use. In this context, we assessed and compared the elevation accuracy of terrain on three forest road surfaces (i.e., asphalt, concrete, and stone), which were derived based on data from three remote sensing technologies (i.e., aerial imaging, airborne laser scanning, and mobile laser scanning) using five geospatial techniques (i.e., inverse distance; natural neighbor; and conversion by average, maximal, and minimal elevation value). Specifically, the elevation accuracy was assessed based on 700 points at which elevation was measured in the field, and these elevations were extracted from fifteen derived forest road maps with a resolution of 0.5 m. The highest precision was found on asphalt roads derived from mobile laser scanning data (RMSE from ±0.01 m to ±0.04 m) and airborne laser scanning data (RMSE from ±0.03 m to ±0.04 m). On the other hand, the lowest precision was found on all roads derived from aerial imaging data (RMSE from ±0.11 m to ±0.23 m). Furthermore, we found significant differences in elevation between the measured and derived terrains. However, the differences in elevation between specific techniques, such as inverse distance, natural neighbor, and conversion by average, were mostly random. Moreover, we found that airborne and mobile laser scanning technologies provided terrain on concrete and stone roads with random elevation differences. In these cases, it is possible to replace a specific technique or technology with one that is similar without significantly decreasing the elevation accuracy (α = 0.05). [ABSTRACT FROM AUTHOR]

Copyright of Journal of Forestry Society of Croatia / Sumarski List Hrvatskoga Sumarskoga Drustva is the property of Forestry Society of Croatia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Forest roads are composed of surface and subsurface layers. Determining the seasonal strength and associated moisture changes in these roads is required to understand their capacity. This study looks at changes in the subgrade layer. Laboratory and field studies were conducted to determine the changes in subgrade conditions by measuring moisture content and subgrade strength for fine-grained, non-plastic soils in Western Oregon. One field and one laboratory experiment were conducted. Drying in the field experiment occurred during the summer months in the absence of rainfall, while the laboratory study allowed drying for 48 h under controlled suction. In both cases, there was a slight reduction in the subgrade's moisture content and no significant improvement in subgrade strength. These findings are supported by the soil physics theory that shows that limited water content reduction is expected for these fine-grained soils, as the numerous tiny soil pores can hold water at high capillary tensions. Adding rock layers adds an insulation effect for the subgrade, further reducing evaporation. Consequently, the moisture content remains high, and there will be little change in subgrade strength during the measurement periods. [ABSTRACT FROM AUTHOR]

The construction of forest roads is considered to be one of the most pronounced anthropogenic impacts on the environment in the forests of national parks. In order to reduce the negative impacts of forest roads on the environment, the planning of a multifunctional network of forest roads must be approached systematically, taking into account a number of aspects. In recent years, a large number of methods have been developed to reach a final solution based on a multitude of criteria, with a particular emphasis on multi-criteria analysis (MCA) in combination with a geographic information system (GIS). This paper presents the possibility of applying the Analytical Hierarchy Process (AHP) in combination with GIS, in order to select suitable locations for the construction of forest roads in the „Fruška gora“ National park. The decision maker evaluated 6 selected criteria to determine the suitability of locations, where “the presence of water sources” and “the risk of fire” were identified as the criteria with the greatest impact on the suit­ability of locations, while the “annual cut” criterion had the least impact.

Forest roadside ditch lines capture and redirect road runoff and typically have erosion control treatments installed therein. Existing methods used to determine the effectiveness of roadside ditch line erosion control treatments estimate fixed fractional reductions in sediment yield. However, fixed fractional reductions do not describe dependence on any measurable physical property of treatment, climate, and the environment. Here, we use additional flow roughness induced by erosion control treatments as a metric that can be used as the basis of estimating treatment effectiveness in varying contexts. We investigate its utility in small‐scale field experiments in western Washington. We measured the physical characteristics of each ditch (e.g., shape, soil texture, and slope) and flow velocities and sediment concentrations for each treatment under multiple experimental discharges. We then used the concept of shear stress partitioning to relate sediment yield from the ditch line erosion treatments to grain shear stress, which is a function of flow roughness (Manning's n) of the respective treatment. We found that (1) a given erosion control treatment produced consistent Manning's n values across multiple replications and sites, with a bare ditch (no treatment) yielding the lowest roughness (n = 0.05) and a densely wattled ditch yielding the highest roughness (n = 0.75); (2) sediment load and calculated grain shear stress data yielded a single positive relationship when data from each experiment were combined, which suggests the effect of additional roughness on grain shear stress is a main driver in the reduction of ditch line sediment load; and (3) in our dataset, fractional erosion reduction had a variable and nonlinear sensitivity to low flow rates (99% of observed flows) for lower roughnesses. Our results demonstrate how additional flow roughness can be used as a general metric to help evaluate the effectiveness of ditch line erosion control treatments for a variety of physical conditions. [ABSTRACT FROM AUTHOR]

Forest roads provide access to remote wooded areas, serving as key transportation routes and contributing to human impact on the local environment. However, large animals, such as bears (Ursus sp.), moose (Alces alces), and caribou (Rangifer tarandus caribou), are affected by their presence. Many publicly available road layers are outdated or inaccurate, making the assessment of landscape objectives difficult. To address these gaps in road location data, we employ CubeSat Imagery from the Planet constellation to predict the occurrence of road probabilities using a SegNet Convolutional Neural Network. Our research examines the potential of a pre-trained neural network (VGG-16 trained on ImageNet) transferred to the remote sensing domain. The classification is refined through post-processing, which considers spatial misalignment and road width variability. On a withheld test subset, we achieve an overall accuracy of 99.1%, a precision of 76.1%, and a recall of 91.2% (F1-Score: 83.0%) after considering these effects. We investigate the performance with respect to canopy coverage using a spectral greenness index, topography (slope and aspect), and land cover metrics. Results found that predictions are best in flat areas, with low to medium canopy coverage, and in the forest (coniferous and deciduous) land cover classes. The results are vectorized into a drivable road network, allowing for vector-based routing and coverage analyses. Our approach digitized 14,359 km of roads in a 23,500 km2 area in British Columbia, Canada. Compared to a governmental dataset, our method missed 10,869 km but detected an additional 5774 km of roads connected to the network. Finally, we use the detected road locations to investigate road age by accessing an archive of Landsat data, allowing spatiotemporal modelling of road access to remote areas. This provides important information on the development of the road network over time and the calculation of impacts, such as cumulative effects on wildlife. [ABSTRACT FROM AUTHOR]

Purpose: Dynamic load from road surface acting on a vehicle has a variable value, depending on road surface profile, movement speed, and stiffness of suspension system, etc. The purpose of this study is to determine the dynamic load from the road surface acting on the multi-purpose forest fire fighting vehicle when the vehicle moves on the forest road by theoretical and experimental methods. Experimental results are compared with the theoretical simulation results to verify the reliability of the simulation model. Methods: This article presents the study results to determine the dynamic load acting on multi-purpose forest fire fighting vehicle by the theoretical and experimental methods when the vehicle moves on the forest road. With the theoretical research method, the authors use the analysis method to separate the structure of the system of many objects and apply Newton–Euler equations to establish the car dynamics model, using the Matlab Simulink software to investigate for determining the dynamic load. By the experimental method, the authors have determined the forest ground roughness to serve as an input parameter for the theoretical survey results and determine the dynamic load acting on the vehicle to compare with the simulation results. Results: The study results of the dynamic load determination show that the error between theory and experiment is the largest of 6.22%. Coinstantaneously, to ensure kinetic safety and durability, when the vehicle moves on the forest road, the vehicle's speed must be less than or equal to 15 km/h. Conclusions: In order to be able to make a meaningful comparison between the findings of the simulation and the outcomes of the experiment, the experiment was performed under the exact identical parameters as the theoretical simulation calculation conditions. The final results of the experiments provided rules that were comparable to those derived from the model's calculations of the survey data. When the extremes of dynamic loads from the simulation and the experimental findings are compared, it can be shown that the largest deviation is 6.22%. This can be considered a demonstration of the correctness and dependability of the dynamic model that the author has constructed and used to identify the load that is acting on the vehicle. [ABSTRACT FROM AUTHOR]

In the realm of transportation system management, various remote sensing techniques have proven instrumental in enhancing safety, mobility, and overall resilience. Among these techniques, Light Detection and Ranging (LiDAR) has emerged as a prevalent method for object detection, facilitating the comprehensive monitoring of environmental and infrastructure assets in transportation environments. Currently, the application of Artificial Intelligence (AI)-based methods, particularly in the domain of semantic segmentation of 3D LiDAR point clouds by Deep Learning (DL) models, is a powerful method for supporting the management of both infrastructure and vegetation in road environments. In this context, there is a lack of open labeled datasets that are suitable for training Deep Neural Networks (DNNs) in transportation scenarios, so, to fill this gap, we introduce ROADSENSE (Road and Scenic Environment Simulation), an open-access 3D scene simulator that generates synthetic datasets with labeled point clouds. We assess its functionality by adapting and training a state-of-the-art DL-based semantic classifier, PointNet++, with synthetic data generated by both ROADSENSE and the well-known HELIOS++ (HEildelberg LiDAR Operations Simulator). To evaluate the resulting trained models, we apply both DNNs on real point clouds and demonstrate their effectiveness in both roadway and forest environments. While the differences are minor, the best mean intersection over union (MIoU) values for highway and national roads are over 77%, which are obtained with the DNN trained on HELIOS++ point clouds, and the best classification performance in forested areas is over 92%, which is obtained with the model trained on ROADSENSE point clouds. This work contributes information on a valuable tool for advancing DL applications in transportation scenarios, offering insights and solutions for improved road and roadside management. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Forestry Society of Croatia / Sumarski List Hrvatskoga Sumarskoga Drustva is the property of Forestry Society of Croatia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Forest roads are crucial for economic development and resource accessibility, especially in regions with extensive wood demand driven by construction growth. These roads require consistent maintenance to prevent structural issues, even though they experience lower traffic. Traditionally, gypsum has been used for soil stabilization due to its cation exchange capability with clay minerals and flocculation properties. However, its water solubility in wet conditions necessitates innovative solutions. This study explores a novel approach by combining gypsum with rice husk ash (RHA), an abundant agricultural waste, to address the challenges posed by expansive and low-bearing clay soils in forest road construction. In this study, an expansive soil with high plasticity and swelling potential is treated with varying combinations of RHA (5–20%) and gypsum (2–6%), followed by curing for 7, 15 and 30 days. Mechanical property tests revealed reduced plasticity and swelling pressure, alongside increased unconfined compressive strength. Microscopic analysis illustrated the formation of calcium silicate hydrate (CSH) and calcium aluminosilicate hydrate (CAH) gels, which possibly contributes to improved stability. This research underscores the potential of sustainable soil stabilization using gypsum and RHA synergy to fortify forest roads against expansive clay soil challenges, promoting eco-friendly and resilient infrastructure solutions. [ABSTRACT FROM AUTHOR]

The soil losses that are caused should be examined by monitoring the forest roads in the periods after they are built. In traditional soil loss determination studies that require intensive labour, due to difficulties in parcel setup, leaks from the connection points of the system, overflow of the material in the storage units and regular follow-up of the precipitation, etc., the system has its disadvantages. In this study, studies were carried out to evaluate the possibilities of using UAV and close range photogrammetry (CRP) methods, which are remote sensing techniques, and to determine the soil losses in forest road cut slopes in semi-arid mountainous areas. In addition, the advantages and disadvantages of the methods are discussed. A 100-m section of the secondary forest road was chosen as the study area. Data acquisition was carried out by UAV and CRP methods in the period of May 2020–November 2020. In the results of the study, the volumetric deformation per unit area results, a − 0.0060 m3m−2 erosion amount and a 0.0046 m3m−2 accumulation amount were determined by UAV. In addition, in the photogrammetric method, a − 0.0050 m3m−2 erosion amount and a 0.0031 m3m−2 accumulation amount were found. When both methods were compared temporally, the processes took approximately 2 times longer in the CRP method. In addition, while the ground sampling distance of DEMs and orthophotos produced with the UAV was 2 cm, it was obtained as 1 cm in the CRP method and terrestrial receptions were found to be 2 times higher resolution. According to the results obtained, the CRP method gives results that are more accurate in such studies. [ABSTRACT FROM AUTHOR]

Unpaved roads are essential as transportation infrastructure. These roads are traditionally built utilizing local soils and aggregates. The application of different materials to improve the strength and the overall performance of these road solutions has been investigated. This study focuses on the assessment of the suitability of reinforcing a fine soil using natural fibres from the forest value chain—specifically, pine needles—for unpaved forest roads. The resilient response of both unreinforced and reinforced soils was assessed with RL-CBR tests (California Bearing tests with repeated load) for different percentages of natural fibres incorporated into the soil. The force–penetration response, CBR value, recoverable and permanent displacements, and equivalent modulus were estimated. The effect of different load stages on the elastic response of both unreinforced and reinforced soils was also evaluated. The CBR values improved with the addition of pine needles; the best response was observed for specimens reinforced with 1% (mass) of these natural fibres (the CBR value increased by 45%). The equivalent modulus also was improved, showing that the stiffness of the soil increased with the inclusion of reinforcement. The findings imply that RL-CBR studies offer a promising method for obtaining important design parameters, especially for unpaved forest roads where investments in soil characterization are frequently limited. [ABSTRACT FROM AUTHOR]

Edge habitats resulting from the construction and maintenance of forest roads favour pioneer, shade-intolerant and disturbance-adapted plant species. The effect of roads on the spread of non-native species has been frequently studied, but few studies have focused upon their effects on native tree species. We studied the effect of forest roads on the expansion dynamics of trembling aspen (Populus tremuloides Michx.) in a boreal forest landscape of eastern Canada. We determined whether roads act as a habitat and dispersal corridor for trembling aspen, and whether populations that established along roads act as a starting point for aspen expansion into adjacent stands. We evaluated the effect of forest roads on the distribution of trembling aspen by surveying the vegetation along 694 km of roads. In 19 stands, we compared the density and age of individuals in 100 m transects established parallel and perpendicular to roads, to determine the role of roads. Trembling aspen is abundant along the forest road network. Forest roads act sometimes as habitat corridors for trembling aspen, but their effects on its density extend only over a short distance (10 m) on each side of the roads. The forest roads did not act as a starting point for the expansion of trembling aspen into adjacent stands. Forest roads are particularly favourable habitats for trembling aspen. Although roads did not act as a starting point for aspen dispersal away from roads, these habitats would be vulnerable to invasion following a disturbance that would reduce the thickness of the organic layer. [ABSTRACT FROM AUTHOR]

Background: The study aimed to identify the influential factors required to prepare landslide vulnerability maps and establish disaster prevention measures for mountainous areas with forest roads. The target area is Sancheok-myeon, Chungju-si, where several landslides have occurred in a narrow area of approximately 3 km × 4 km. As the area has the same rainfall and vegetation conditions, the influences of the physico-mechanical characteristics of the soil in accordance with compaction and topographic characteristics could be analyzed precisely. Methods: Geological surveying, sampling, and laboratory testing assessed landslide risk in the study area, and data including unit weight, specific gravity, porosity, water content, soil depth, friction angle, cohesion, slope angle, profile/plan curvature, TWI were obtained. Preprocessing and screening such as min-max normalization and multicollinearity were conducted for the data in order to eliminate overestimation of each factor's effectiveness. The influence of each factor was analyzed using logistic regression (LR), structural equation modeling (SEM), extreme gradient boosting (XGBoost), and light gradient boosting machine (LightGBM). Results: All methods showed that soil depth has the greatest impact on landslide occurrence. Friction angle, slope angle, and porosity were also selected as influential factors, although each method ranked them slightly differently. Topographic factors, such as plan curvature, profile curvature, and the topographic wetness index, had minimal influence. This appears to be because landslides near forest roads are more affected by how well compaction was performed during banking than by the concave or convex shape of the slope. This study presents analysis results for an area with the same rainfall and vegetation conditions; therefore, the analysis of the influence of the physico-mechanical characteristics of the soil and topography was more precise than when comparing landslides occurring in different regions. Our results may be helpful in preparing landslide vulnerability maps. [ABSTRACT FROM AUTHOR]

Sustainable forest and emergency management require comprehensive data on the forest road network and its condition. This paper presents the final framework of the INFOROAD project (https://inforoad.karteco.gr/), which integrates cutting-edge remote sensing and machine learning technologies for automated periodic extraction and monitoring of the forest road network. The framework includes gravel road extraction, road graph extraction, and gravel road condition monitoring, with a focus on the periurban forest in Thessaloniki. The road extraction employs the U-TAE network architecture, with a proposed modification using inverted residual blocks for improved accuracy. Road graph extraction involves creating a graph from road segmentation output or OSM data, enabling efficient road segment analysis. Gravel-road width calculation utilizes road segmentation results and a series of image processing steps, while road condition monitoring employs ML/AI classification algorithms. Worldview 3 high-resolution satellite images and various auxiliary data sources (e.g. DEM) are used as input, including field measurements for the training of classification algorithms. Results showcase the effectiveness of the proposed framework, with gravel road extraction accuracy improved by the modified U-TAE model. Regarding gravel road condition monitoring, algorithms achieving satisfactory results are identified, despite the challenges that arise, due to the significant surface and texture variations in forest and agricultural roads. A WebGIS platform facilitates information presentation, user interaction, and management of geospatial information, supporting various functionalities such as layer management and spatial data visualization. The INFOROAD project represents a significant advancement in leveraging technology for sustainable forest road management and emergency preparedness. Future steps may involve further enhancements and adaptations for improvement of results. [ABSTRACT FROM AUTHOR]

Multifunctional forest management should provide the opportunity to create, conserve, modify or eliminate forest roads. Within protected areas, it is difficult to make a single assessment of the degree of accessibility to different forest areas, having to mediate among productive forestry, protection needs and other benefits deriving from forest stands. A GIS-based methodology, with the support of a Forest Information System (FIS) and available Forest Plans for the study area, were applied to create an accessibility map (based on the forest roads network) for the Abruzzo, Lazio, and Molise National Park (PNALM). Results were related to several FIS metadata, highlighting that accessibility in the study area was sufficient, but not optimal, in the productive management units, being rather poor in those where soil protection and biodiversity conservation are the main functions (only 38.8% of them were accessible). Forest roads density (28.5 m ha−1) was not homogeneously distributed within the study area and the ratio between forest road length (199.4 km) and planned forest surface (13,355.3 ha) is only 14.9 m ha−1. In contrast to what is commonly found in forest accessibility works, the innovative element of this study was the involvement of PNALM's technical office in evaluating the results and exploring the opportunity to adopt a different policy for forest roads network management. [ABSTRACT FROM AUTHOR]

Knowledge about the condition and location of forest roads is important for forest management. Coupling accurate forest road information with planning and conservation strategies supports forest resource management. In Canada, spatial data of forestry road networks are available provincially; however, they lack spatial accuracy, and up-to-date information on key attributes such as road width is missing. In this study, we apply a novel approach to update forest road networks and characterize road conditions in Ontario's Boreal and Great Lakes—St. Lawrence (GLSL) Forest regions. We use airborne laser scanning (ALS), to facilitate the identification of forest roads across densely forested landscapes. We categorized roads into four classes based on driveable width, edge vegetation, as well as surface and edge degradation as derived from high-density Single Photon LiDAR (SPL) data. Using a novel road extraction method, we produced a road probability raster and map road centerlines. We validated road location and attribute information using Global Navigation Satellite System (GNSS) ground truth data in two Ontario forest management units, in the boreal forest and the GLSL. Road segments in some regions have been altered to account for land cover changes, such as flooding or fallen trees. In other situations, the road path may deviate from the planned layout of the road, which is not always followed in the field. Our results highlight inaccuracies in the existing road networks, with 30 per cent of 'Full access' roads and 29 per cent of 'Partial access' roads being undriveable by standard vehicles and 45 per cent of 'Status unknown' roads, which make up 48 per cent of the pre-existing network, being driveable by standard vehicles. Results show that the average positional accuracy of updated road centerlines is 0.4 m, and the average road width error is 2 m. The production of spatially accurate forest road networks and road attribute information is important for characterizing large road networks for which often minimal information is available. [ABSTRACT FROM AUTHOR]

Autonomous legged navigation in unstructured environments is still an open problem which requires the ability of an intelligent agent to detect and react to potential obstacles found in its area. These obstacles may range from vehicles, pedestrians, or immovable objects in a structured environment, like in highway or city navigation, to unpredictable static and dynamic obstacles in the case of navigating in an unstructured environment, such as a forest road. The latter scenario is usually more difficult to handle, due to the higher unpredictability. In this paper, we propose a vision dynamics approach to the path planning and navigation problem for a quadruped robot, which navigates in an unstructured environment, more specifically on a forest road. Our vision dynamics approach is based on a recurrent neural network that uses an RGB-D sensor as its source of data, constructing sequences of previous depth sensor observations and predicting future observations over a finite time span. We compare our approach with other state-of-the-art methods in obstacle-driven path planning algorithms and perform ablation studies to analyze the impact of architectural changes to our model components, demonstrating that our approach achieves superior performance in terms of successfully generating collision-free trajectories for the intelligent agent. [ABSTRACT FROM AUTHOR]

Recent decades have seen increased temperatures and precipitation in the Nordic countries with long-term projections for reduced frost duration and depth. The consequence of these trends has been a gradual shift of delivery volumes to the frost-free season, requiring more agile management to exploit suitable weather conditions. Bearing capacity and trafficability are dependent on soil moisture state and in this context two satellite missions offer potenially useful information on soil moisture levels; NASA's SMAP (Soil Moisture Active Passive) and ESA's Sentinel-1. The goal of this pilot study was to quantify the performance of such satellite-based soil moisture variables for modeling forest road bearing capacity (e-module) during the frost-free season. The study was based on post-transport registrations of 103 forest road segments on the coastal and interior side of the Scandinavian mountain range. The analysis focused on roads of three types of surface deposits. Weekly SMAP soil moisture values better explained the variation in road e-module than soil water index (SWI) derived from Sentinel-1. Soil Water Index (SWI), however, reflected the weather conditions typical for operations on the respective surface deposit types. Regression analysis using (i) SMAP-based soil dryness index and (ii) its interaction with surface deposit types, together with (iii) the ratio between a combined SMAP_SWI dryness index and segment-specific depth to water (DTW) explained over 70% of the variation in road e-module. The results indicate a future potential to monitor road trafficability over large supply areas on a weekly level, given further refinement of study methods and variables for improved prediction. [ABSTRACT FROM AUTHOR]

Forest road densities which are too high increase production costs, planting area loss, and environmental impacts. To solve this problem and plan an adequate forest road density, it is necessary to analyze and consider the topography, road network-related costs, and the type and number of machines to meet the required wood production. The aim of this study was to determine the current road density (RD), the optimal economic road density (ORD) and operational road density (OD) in flat and sloping site conditions for the full tree harvesting system in Southern Brazil. The RD was determined by the ratio of total road lengthand the total productive area. ORD was determined based on the transport geometry model, considering the minimization of the sum of unit costs of road construction and maintenance, loss of productive area, mitigation of road impacts, and wood extraction. The OD was determined considering the minimum number of extraction machines necessary to meet the annual demand for wood. All forest road densities were lower in flat site conditions than in sloping areas. In both conditions (flat and sloping), RDs (126 and 180 m ha−1, respectively) were higher than ORDs (53 and 65 m ha−1, respectively), which were lower than ODs (92 and 123 m ha−1, respectively). Therefore, OD can be an alternative parameter for managers to use in forest road network planning, mainly in conditions where ORD is not feasible to adopt. [ABSTRACT FROM AUTHOR]

The significant increase in hiking, wood extraction, and transportation activities exerts a notable impact on the environmental balance along trails and forest roads in the form of soil degradation. The aim of this study was to develop a Deformation Classification Model for the surface of a multi-use trail, as well as to calculate sediment deposition and generate a flood hazard map in a partially forested region. The eBee X mapping Unmanned Aerial Vehicle (UAV) equipped with the senseFly S.O.D.A. 3D camera and Real-Time Kinematic (RTK) technology flew over the study area of 149 ha in Northern Greece at an altitude of 120 m and achieved a high spatial resolution of 2.6 cm. The specific constellation of fixed-wing equipment makes the use of ground control points obsolete, compared to previous, in most cases polycopter-based, terrain deformation research. Employing the same methodology, two distinct classifications were applied, utilizing the Digital Surface Model (DSM) and Digital Elevation Model (DEM) for analysis. The Geolocation Errors and Statistics for Bundle Block Adjustment exhibited a high level of accuracy in the model, with the mean values for each of the three directions (X, Y, Z) being 0.000023 m, −0.000044 m, and 0.000177 m, respectively. The standard deviation of the error in each direction was 0.022535 m, 0.019567 m, and 0.020261 m, respectively. In addition, the Root Mean Square (RMS) error was estimated to be 0.022535 m, 0.019567 m, and 0.020262 m, respectively. A total of 20 and 30 altitude categories were defined at a 4 cm spatial resolution, each assigned specific ranges of values, respectively. The area of each altitude category was quantified in square meters (m2), while the volume of each category was measured in cubic meters (m3). The development of a Deformation Classification Model for the deck of a trail or forest road, coupled with the computation of earthworks and the generation of a flood hazards map, represents an efficient approach that can provide valuable support to forest managers during the planning phase or maintenance activities of hiking trails and forest roads. [ABSTRACT FROM AUTHOR]

The main tasks of this research are an extended analysis of the technological rut formation process's geometric, force, and energy characteristics as a result of repeated passage of a forest machine on the soil surface. Existing experimental studies of the rutting process are associated with significant material costs and disruption of the forest ecosystem. The purpose of this study is to obtain similar experimental data in laboratory conditions, as well as establishing the correspondence of these experimental results to the results of field studies. The experiments were carried out on the specialized "soil channel" stand of Technical University in Zvolen (Slovakia), as well as in natural conditions in Brody Forestry of the Lviv Region (Ukraine). Geometric track characteristics were determined by length gauges. Power and energy characteristics of the track development process were determined using dynamometers, ammeters, and voltmeters. The physical and mechanical characteristics of the soil with which the mover interacted were determined by a dynamic hardness tester, a penetrometer, and a moisture meter. The characteristics of rut development processes in natural and laboratory conditions are similar to each other. This makes it possible to carry out a wide range of studies of a wheel with soil on a specialized stand and save considerable money during the implementation of full-scale experiments. So, the process of track development can be analyzed with the help of the geometric, force, and energy characteristics of the "wheel-soil" system obtained on laboratory equipment. [ABSTRACT FROM AUTHOR]

In the middle of the last century, a system of field protective forest belts was created in North-Eastern Bulgaria to protect agricultural lands and increase yields from cereals and other agricultural crops. Forest roads were also built, ensuring the implementation of silvicultural activities in field protective forest belts. It was found what part of the forest roads in the region of Dobrudzha are stabilized with crushed stone, and the rest are dirt roads without stabilization. It has been established what part of the forest roads in the region are stabilized with crushed stone, and what part are dirt roads without stabilization. [ABSTRACT FROM AUTHOR]

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Forest roads are very important communication routes, ensuring the implementation of all functions of forests and forest management. According to the law, their status can be considered at least as specific. They are included in the category of forest land, but they are not public roads. At the same time, they are linear objects, that is types of buildings, specifically building objects. This fact has significant consequences for the investment and construction process in the field of construction and reconstruction of forest roads. The subject of the study is the analysis of forest roads on a theoretical and practical level. Apart from the dogmatic approach, forest roads should be confronted with the institutions of administrative substantive law, such as public goods (facilities) and special areas.

The planning and implementation of surveillance of state territory in forested border areas, especially mountainous areas, is considered to be highly complex. This is illustrated by the example of the difficulties the European Union faced in controlling the 2015 European migration crisis. Thereby, Croatia has the difficult task of protecting the borders of the Union because a particular problem on the Western Balkan Route is the so-called bottleneck to Slovenia in the area of the Municipality of Donji Lapac, which consists of the green border with Bosnia and Herzegovina. Consequently, by using the example of planning multi-purpose forest roads, the aim of this paper is to propose the inclusion of the road network of border management units of mountain areas in the control system of the state's green border, which, in this paper, includes its surveillance and protection by land for the purpose of national security. The research was conducted on the example of the Visočica–Lisac border management unit in the Municipality of Donji Lapac. The results of the research indicate a possible solution to the control of the border management unit by establishing a two-level surveillance system. The higher level consists of strategically defined surveillance points and corresponding multi-purpose forest roads designed on a tactical level. At this level, the priority is protection or, more precisely, defense of the state border. The lower level consists of tactically determined surveillance points with corresponding multi-purpose forest roads designed on the operational level. In addition to protecting the state border, this level would also have the task of protecting the forest, that is, monitoring the area of the management unit. [ABSTRACT FROM AUTHOR]

As one of the main components of forest operations and sustainable management, forest roads affect the vegetation communities around the road. In this study, the effects of the edge of forest roads were investigated to understand the changes caused by the network of forest roads on the Hyrcanian forest ecosystem in northern Iran. In order to investigate the impact of forest roads on the biodiversity of herbaceous species, tree regeneration and lichen, sampling was used at different distances from the road in two controlled and harvested areas. The effects of roads on vegetation diversity in relation to soil characteristics were also investigated. The results showed that harvesting caused the destruction and reduction of tree, herbaceous and lichen regeneration, but the physical and chemical properties of the soil were not affected. The distance from the road has affected the diversity and richness of herbaceous and lichen, tree regeneration and all physical and chemical characteristics of the soil (except C). There was a significant correlation between most of the physical and chemical properties of the soil with the regeneration of trees and herbaceous species. Also, most of the physical and chemical properties of soil have increased with increasing distance from the road. Results showed that the buffering effect of the roadside in these forests up to a distance of 45 m had an effect on diversity and richness. Also, the results of this study are consistent with the fact that the road affects the biodiversity and properties of the forest soil. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine the forest road construction area and environmental impact area and to determine the tree injuries caused by forest road construction, the filling area covering the stand, and the distances of the trees directly affected by the tree injuries from the road axis. For this objective, a 700-m section of the forest road number 194 within the boundaries of the Alabarda Forest Management Sub-Directorate (Bolu/Turkey) was selected as the study area. The forest road environmental impact area was found by determining the rolling boundary of the backfill material with the differential global positioning system (DGPS) device. In addition, the position of the trees in this area in relation to the road and their damage conditions were determined, and wound sizes were measured. As a result of the study, the road construction impact area was 46479 m2, the average spread distance of the backfill material was 50.34 m, the average distance of the damaged trees from the road was 28.25 m, and the average distance of the trees that were not damaged was 35.52 m. In addition, a total of 1477 trees were identified in the construction impact area and 427 of these trees were damaged. According to the results of the statistical analyses, a statistically significant positive correlation was determined between bark wound area and diameter. In addition, a statistically significant negative correlation was determined between the distance of the trees from the road axis and the wound area and the height of the backfill. [ABSTRACT FROM AUTHOR]

Vehicles are an important source for N deposition that may negatively impact roadside ecosystems. While elevated roadside N deposition has been found in many locations, it is not yet known if vehicle emissions cause measurable increases of N deposition in complex, mountainous terrain adjacent to roads. To address this, this study investigated the effect of vehicle N emissions on throughfall (through trees) and open N deposition in a high traffic corridor in mountainous terrain of Rocky Mountain National Park, Colorado, USA. We measured bulk (wet + dry) atmospheric N deposition in throughfall and open samplers along two transects of 750 (throughfall) and 225 (open) m moving away from the road using ion exchange resin (IER) collectors. Contrary to most studies of roadside N deposition, we found no influence of road proximity on inorganic N deposition in throughfall or open sites, possibly due to terrain complexity. Interactions with vegetation modified regional N deposition; throughfall sites had 69% higher nitrate (NO3−) deposition than open sites and larger trees were associated with higher ammonium (NH4+) deposition as compared to smaller trees. When comparing to regional sites that are part of national monitoring networks, we confirmed that our estimates were unaffected by vehicle emissions as our throughfall IER collectors had similar total inorganic N deposition as wet + dry deposition from regional sites (8.64–13.56 vs 10.72–12.14 g N ha−1 day−1, respectively). These findings do not negate vehicles as a local source of N emissions but suggest elevated N deposition adjacent to busy roads cannot be assumed for complex terrains. Instead, environmental variables may be more important drivers than proximity to roads in topographically complex ecosystems. [ABSTRACT FROM AUTHOR]

The design and assessment of forest and rural road pavements made from unbound natural and recycled materials require the careful determination of their physical-mechanical properties. The fundamental parameter for characterizing the soil material property is considered to be the resilient modulus Mr. The generally accepted alternative solution for its calculation is the cyclic CBR test, which uses standard CBR testing equipment. To perform tests on intact specimens and under stress conditions corresponding to expected states of stress in a pavement structure, an updated cyclic CBR test is proposed. In contrast to the standard cyclic CBR test, the applied loading force for repeated loadings is not determined in the first loading step by the plunger penetration to the prescribed depth, but by the stress value that is expected in an actual pavement structure. The updated test was verified on 240 tested specimens taken from a total of 40 soil samples belonging to nine soil types according to the USCS system. The resilient modulus results obtained are compared with those obtained using the standard cyclic CBR test and the cyclic triaxial test. [ABSTRACT FROM AUTHOR]

An environmentally friendly and economically efficient forest road network is the key to sustainable forest management, and it is essential to evaluate the sustainability of an established forest road network and to optimize the forest road network based on sustainability criteria. This study proposes a sustainability evaluation method for forest road networks. The evaluation index system was constructed by selecting 12 indices from the social, economic, and ecological dimensions. To improve the credibility of the weighting of the evaluation indicators, the evaluation indicators were assigned subjective and objective weights by the analytic hierarchy process and the entropy weight method, respectively, and the game theory idea was used to comprehensively assign the weights. The study area was chosen to be the Taohuajiang State-Owned Forest Farm, which is a national forest park and is also an ecological public welfare forest. The development of the forest road network in the social, economic, and environmental dimensions was calculated by adopting the evaluation method proposed in this study, and the sustainability of the forest road network in each subdivision of the study area was determined, to provide a detailed theoretical basis for the management to carry out the upgrading of the sustainability of the forest road network. The results derived from the evaluation methodology show that the sustainable development of the forest road network in the study area is "excellent". At the same time, the level of sustainability of the forest road network in different areas of the study area was also evaluated. Finally, this paper puts forward policy recommendations for optimizing the sustainable development of forest road networks. The original sustainability evaluation method in this paper provides a scientific tool for assessing the degree of sustainable development of forest road networks, which contributes to optimizing the forest road networks. [ABSTRACT FROM AUTHOR]

Owing to society's growing ecological awareness, researchers and car manufacturers have increasingly been focusing on the adverse impact of transport on the environment. Many scientific publications have been published addressing the influence of a variety of factors on the exhaust emissions generated by vehicles and machinery. In this paper, the authors present an analysis of the exhaust emissions of components such as CO, THC, and NOx in relation to the type and condition of the road surface. The analysis was performed on a heavy-duty truck designed for carriage of timber. The investigations were carried out with the use of the PEMS equipment (portable emission measurement system) on bitumen-paved roads and unpaved forest access roads. The portable measurement system allowed for an accurate determination of the influence of the road conditions on the operating parameters of the vehicle powertrain and its exhaust emissions. Additionally, the authors present the influence of the type of road surface on the vehicle fuel consumption calculated based on the carbon balance method. [ABSTRACT FROM AUTHOR]

Context: Uneven-aged forest management is sometimes seen as offering interesting compromises between timber production and other important ecosystem services, compared to even-aged approaches. However, uncertainties remain concerning its impacts over longer time periods and broader spatial scales, as larger areas and further roads are required to harvest the same amount of wood. Objectives: We compared the large-scale and long-term impacts of uneven-aged and even-aged managements on the composition, road density and fragmentation of a landscape composed of northern temperate and boreal forests, and presenting frequent forest fires. Methods: We simulated an 800,000 ha forested landscape in the Mauricie region (Quebec, Canada) over a 150-year planning horizon with the LANDIS-II model and an extension that simulates forest road construction. We compared 30 different management scenarios that varied the proportion of even- and uneven-aged managements, the level of aggregation of the harvested areas, and the presence of pre-existing forest roads. Results: Compared with even-aged management, uneven-aged management increased (i) the density of forest roads and their operational costs, (ii) the amount of old forests, and (iii) their fragmentation. Aggregating harvested areas did not noticeably reduce road density, and the presence of an initial road network had no long-term effects. Differences in landscape fragmentation between scenarios were reduced in the northern region of the landscape due to the fire regime. Conclusions: Choosing uneven-aged over even-aged management represents a trade-off between the amount of old forests in the landscape and three variables related to roads: their density, their related cost, and the fragmentation per se that they generate, This trade-off seems to disappear in the presence of stand-replacing disturbances in the landscape and is unlikely to be improved by aggregating the harvested areas. [ABSTRACT FROM AUTHOR]

Edge habitats resulting from the construction and maintenance of forest roads favour pioneer, shade-intolerant and disturbance-adapted plant species. The effect of roads on the spread of non-native species has been frequently studied, but few studies have focused upon their effects on native tree species. We studied the effect of forest roads on the expansion dynamics of trembling aspen (Populus tremuloides Michx.) in a boreal forest landscape of eastern Canada. We determined whether roads act as a habitat and dispersal corridor for trembling aspen, and whether populations that established along roads act as a starting point for aspen expansion into adjacent stands. We evaluated the effect of forest roads on the distribution of trembling aspen by surveying the vegetation along 694 km of roads. In 19 stands, we compared the density and age of individuals in 100 m transects established parallel and perpendicular to roads, to determine the role of roads. Trembling aspen is abundant along the forest road network. Forest roads act sometimes as habitat corridors for trembling aspen, but their effects on its density extend only over a short distance (10 m) on each side of the roads. The forest roads did not act as a starting point for the expansion of trembling aspen into adjacent stands. Forest roads are particularly favourable habitats for trembling aspen. Although roads did not act as a starting point for aspen dispersal away from roads, these habitats would be vulnerable to invasion following a disturbance that would reduce the thickness of the organic layer.