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Peatlands in the western boreal plains of Canada are important ecosystems as they store over two percent of global terrestrial carbon. However, in recent decades, many of these peatlands have been fragmented by access roads constructed for resource extraction and transportation, challenging their carbon storage potential. To investigate how roads have been impacting tree and shrub growth and productivity in these peatlands, this study was conducted in a forested bog and woody fen in Carmon Creek, Alberta, Canada. In 2017, vegetation surveys were conducted along 20 m transects that extended on both sides of the road with 4 m2 circular plots at 2, 6 and 20 m distance from the road and were followed by disc or core collection from woody stems. Within 20 m of the road at the bog site, we observed a shift towards significantly larger radial growth of trees in the downstream areas (t = 3.23, p = 0.006) where water table position was deeper, while at the fen site, radial growth of tall shrubs had little response to the road. Combining the effects of direct tree clearing and hydrology induced shifts in growth, aboveground net primary productivity (NPPag) post-road construction was reduced significantly in areas where vegetation was cleared during the road construction (i.e., upstream areas of the bog: t = 5.21, p < 0.0001 and downstream areas of the fen: t = 2.64, p = 0.07). Substantially lower NPPag around the road construction areas compared to reference areas shows tremendous loss of carbon sink potential of trees and shrubs after road construction through peatlands. Altogether, roads constructed through peatlands perpendicular to the water flow may shift long-term carbon sinks into sources of carbon, at least for the initial few years following road construction.

To address the issues of signal loss and insufficient accuracy of traditional GNSS (Global Navigation Satellite System) navigation in agricultural machinery sheds and farm access road environments, this paper proposes a high-precision mapping method for such complex environments and a real-time localization system for agricultural vehicles. First, an autonomous navigation system was developed by integrating multi-sensor data from LiDAR (Light Laser Detection and Ranging), GNSS, and IMU (Inertial Measurement Unit), with functional modules for mapping, localization, planning, and control implemented within the ROS (Robot Operating System) framework. Second, an improved LeGO-LOAM algorithm is introduced for constructing maps of machinery sheds and farm access roads. The mapping accuracy is enhanced through reflectivity filtering, ground constraint optimization, and ScanContext-based loop closure detection. Finally, a localization method combining NDT (Normal Distribution Transform), IMU, and a UKF (Unscented Kalman Filter) is proposed for tracked grain transport vehicles. The UKF and IMU measurements are used to predict the vehicle state, while the NDT algorithm provides pose estimates for state update, yielding a fused and more accurate pose estimate. Experimental results demonstrate that the proposed mapping method reduces APE (absolute pose error) by 79.99% and 49.04% in the machinery sheds and farm access roads environments, respectively, indicating a significant improvement over conventional methods. The real-time localization module achieves an average processing time of 26.49 ms with an average error of 3.97 cm, enhancing localization accuracy without compromising output frequency. This study provides technical support for fully autonomous operation of agricultural machinery.

Natural resource extraction in large undeveloped areas—such as the Bristol Bay watershed in Southwest Alaska—often necessitates construction of roads that contribute substantial environmental risks. Herein, we attempt to address risks from a proposed mine transportation corridor in a virtually roadless watershed that crosses important salmon streams and rivers. The Bristol Bay watershed supports the largest sockeye salmon fishery in the world. A proposed 138 km permanent access road would connect a porphyry copper/gold deposit to a deep-water port. Of 64 potential stream crossings, salmonid spawning migrations may be impeded by culverts at 36 crossings, 32 of which contain restricted upstream habitat. After cessation of mine operations, assuming typical maintenance practices, 10 or more of the 32 streams with restricted upstream habitat would likely be entirely or partly blocked at any time. Consequently, salmon passage—and ultimately production—would be reduced in these streams, and they would likely not be able to support long-term populations of resident species. Additional long-term risks associated with operation of the road include filling or alteration of National Wetland Inventory aquatic habitats; spills of highly toxic xanthate or cyanide due to truck accidents; and reduced habitat quality due to dust production from traffic. We discuss our methodology, and information needs, in the context of Environmental Impact Statements that set the stage for decisions regarding future mining projects.

It is found that the slope of access roads influences adds to flattening of nonmining pit walls where the access roads are driven. Aiming to determine the over-flattening of nonmining pit walls, the quick and accurate analytical method is developed. It is proved that the increase of the slope of access roads to the maximum possible values (20–24%) enables reduction in stripping by 20–40% in deep open pit mines. The mining efficiency in case of steep slopes, aside from extra flattening of nonmining pit walls, is also influenced by the depth of transition to such slopes and the transportation capacity of the access roads depending on distribution of mining operations along the depth of an open pit mine. It is demonstrated that it is most reasonable to gradually increase the slope of access roads with the mining depth, starting from the initial value (8%) and up to the maximum governed by technical requirements and operating conditions.

Since their appearance at the end of the 19th century, traffic lights have been the primary mode of granting access to road intersections. Today, this centuries-old technology is challenged by advances in intelligent transportation, which are opening the way to new solutions built upon slot-based systems similar to those commonly used in aerial traffic: what we call Slot-based Intersections (SIs). Despite simulation-based evidence of the potential benefits of SIs, a comprehensive, analytical framework to compare their relative performance with traffic lights is still lacking. Here, we develop such a framework. We approach the problem in a novel way, by generalizing classical queuing theory. Having defined safety conditions, we characterize capacity and delay of SIs. In the 2-road crossing configuration, we provide a capacity-optimal SI management system. For arbitrary intersection configurations, near-optimal solutions are developed. Results theoretically show that transitioning from a traffic light system to SI has the potential of doubling capacity and significantly reducing delays. This suggests a reduction of non-linear dynamics induced by intersection bottlenecks, with positive impact on the road network. Such findings can provide transportation engineers and planners with crucial insights as they prepare to manage the transition towards a more intelligent transportation infrastructure in cities.

1. Human activities have dramatic effects on the distribution and abundance of wildlife. Increased road densities and human presence in wilderness areas have elevated human-caused mortality of grizzly bears and reduced bears' use. Management agencies frequently attempt to reduce human-caused mortality by managing road density and thus human access, but the effectiveness of these actions is rarely assessed. 2. We combined systematic, DNA-based mark-recapture techniques with spatially explicit capture-recapture models to estimate population size of a threatened grizzly bear population (Kettle-Granby), following management actions to recover this population. We tested the effects of habitat and road density on grizzly bear population density. We tested both a linear and threshold-based road density metric and investigated the effect of current access management (closing roads to the public). 3. We documented an c. 50% increase in bear density since 1997 suggesting increased landscape and species conservation from management agencies played a significant role in that increase. However, bear density was lower where road denisities exceeded 0.6 km/km² and higher where motorised vehicle access had been restricted. The highest bear densities were in areas with large tracts of few or no roads and high habitat quality. Access management bolstered bear density in small areas by 27%. 4. Synthesis and applications. Our spatially explicit capture-recapture analysis demonstrates that population recovery is possible in a multi-use landscape when management actions target priority areas. We suggest that road density is a useful surrogate for the negative effects of human land use on grizzly bear populations, but spatial configuration of roads must still be considered. Reducing roads will increase grizzly bear density, but restricting vehicle access can also achieve this goal. We demonstrate that a policy target of reducing human access by managing road density below 0.6 km/km², while ensuring areas of high habitat quality have no roads, is a reasonable compromise between the need for road access and population recovery goals. Targeting closures to areas of highest habitat quality would benefit grizzly bear population recovery the most.

The Surabaya City has a rapid infrastructure development as proven by the increasing value of land. One of the infrastructure developments is the construction of Ahmad Yani's Frontage Road. The value of land in Frontage Ahmad Yani continues to increase due to various factors. The purpose of this study analyzes what variables affect land value by using a descriptive analysis method based on journals and previous research. The results of this study uncovered four dominant variables that influence land values, namely location, land characteristics, externalities, and accessibility.

In the article, a mathematical model for determining the parameters of the access road for catastrophic situations on highways passing through the mountainous area is developed. The reliability of the mathematical model is proven by experiment.

The main idea of this project was to create an access road for the tourists and also to improve the winter sports conditions, especially the ski, in the beautiful Parag Mountains. It was a very challenging project, as the road takes until 1600 m at alpine elevation. One of the structures was delivered and assembled in November 2019, in 3 weeks of hard weather conditions, with a 5 working men team.

The construction of overhead transmission lines in mountainous areas poses a significant challenge when it comes to foundation construction. The type of foundation selected in these areas has a direct impact on equipment selection and access road planning. Fujian Province, located on the southeastern coast of China, is predominantly hilly and mountainous. Therefore, selecting an appropriate foundation for overhead transmission lines is crucial for successful mechanized construction of transmission lines in this region. In this study, we aimed to enhance the economy of mechanized construction of the foundation of the 220 kV overhead transmission lines in Fujian Province. We analyzed the typical geological conditions and foundation reactions in the area and compared the construction costs of mechanical pile foundations, mechanical digging foundations, and rock anchor foundations. The results show that the mechanical pile foundation requires the least amount of concrete when the foundation reaction of the 220 kV suspension tower is less than 1700 kN and the foundation reaction of the 220 kV tension tower is less than 1300 kN. Additionally, the quantity of the rock anchor foundation is less than that of the digging foundation. In terms of cost, the rock anchor foundation is the most economical, followed by the mechanical pile foundation and then the digging foundation.