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An important source of coniotic air pollution is mining activity in quarries, what produces large quantities of particulate matter that affects human health and ecosystems. The purpose of this work is to determine by the gravimetric method, the content of fines (particles smaller than 0.074 mm) in the unpaved roads from the front of "La Molina" quarries to production centers from Canteras Mariel Base Business Unit as well as in the aggregate storage piles. Samples of 30 g taken at 11 points of the unpaved roads and in the piles of each type of aggregate (granite, sand, gravel and macadam) were analyzed. A 24 .9% concentration of average fines for unpaved roads, a figure that doubles the values reported in the literature for extractive activities. It was also found that due to the action of wind and rain, these fines adhere mostly to the assortments of greater granulometry arranged in piles, what causes the production to be contamination to be contaminated. [ABSTRACT FROM AUTHOR]

Driving scene understanding is an essential technique for realizing autonomous driving. Although many large-scale datasets for autonomous driving have enabled studies in terms of driving scene understanding, unpaved dirt roads have not been considered as their target driving environment. Drivable region identification is important in dirt roads to prevent damage to the vehicle and passengers. Semantic segmentation of camera images and lidar point clouds have been used to recognize the environment around an autonomous vehicle. The road and objects are recognized by classifying image pixels and point clouds into semantic classes. In this study, we introduce a perception method for drivable region identification on dirt roads through fusion of image and point cloud semantic segmentation. Our approach includes an image semantic segmentation algorithm and a point cloud semantic segmentation algorithm, which we combine into a bird’s-eye-view grid map format. To transform the point-wise drivable region identification results into the area-wise information, we adopt the alphashape algorithm. Speed improvements are made by using small proportion of drivable points, and the accuracy degradation is compensated by accumulating the perception results along the time. [ABSTRACT FROM AUTHOR]

Copyright of Annual Set the Environment Protection / Rocznik Ochrona Środowiska is the property of Koszalin University of Technology 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.)

Edge effects threaten organisms and ecological processes in habitat remnants, but they have been poorly studied in non-humid forests such as cerradão, a tropical dry forest sometimes derived from fire-suppressed savanna in Brazil. The diverse ecosystem functions performed by arthropods may be disrupted by edge effects, and there is pressing need for more studies on this subject. We sampled fragments of cerradão facing either a road or fire breaks, assessing edge effects in: beta diversity and community composition of epigaeic (litter-dwelling) arthropod orders, ant species, and ant functional groups; ant species richness and diversity; leaf litter depth; and colony residence time of a predatory ground-dwelling ant, Odontomachus chelifer (Ponerinae). None of the variables measured differed between edge and interior of the sites sampled. Dry forests have high micro-climatic variations caused by discontinuities in the canopy cover and, as such, changes in abiotic variables in cerradão edges might not be as clear as those observed in tropical rainforests. Our study demonstrates that edge effects may not be so prevalent in cerradão facing roads or fire breaks, which possibly increases the chances of survival of a higher fraction of the original arthropod fauna compared to rainforest fragments. [ABSTRACT FROM AUTHOR]

Field experiences have shown that the use of geosynthetics improves the trafficability of unpaved roads on soft subsoil. Specifically, the thickness of the base course and therefore the amount of high quality geomaterials e.g. crushed gravel can be reduced. Until now, the design is mainly based on empirical approaches based on results from experiments obtained in field tests. The thickness of the base course is increased until an adequate bearing capacity of the unpaved road is reached. There are extensive studies throughout the literature that confirm the mechanism of the bearing capacity improvement, but mostly cover only individual effects such as the influence of the bearing layer thickness at constant subsoil strength. Therefore, they cannot be extended to a general theory and design approach that can account for all of the important variables. To investigate the effectiveness of different geosynthetics in unpaved roads a series of loading tests on geotextile reinforced, unpaved roads were carried out both in the laboratory and in the field. Beside the bearing strength and stiffness of the soft subsoil, the base course thickness as well as the type, and hence the strength of the geosynthetics were varied in the tests. This paper presents a brief summary of the experimental results that may be used to evaluate models to predict the bearing capacity of unpaved roads. [ABSTRACT FROM AUTHOR]

Copyright of Istanbul Commerce University Journal of Social Sciences / İstanbul Ticaret Üniversitesi Sosyal Bilimler Dergisi is the property of Istanbul Commerce University Journal of Social Sciences 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 characteristics of fugitive dust emitted from vehicles traveling on unpaved dirt roads were measured using a suite of instruments including a real-time fugitive dust sampler. The fugitive dust sampler is formed from a combination of a large particle inlet and an optical particle spectrometer that reports particle sizes from 6 to 75 µm. The large particle inlet permits the sampling of particles up to 75 µm with only a moderate dependence of sampling efficiency on wind-speed. Measurements made with the sampler showed that particles as large as ∼50 µm were suspended from vehicular movement on the dirt roads, with the mode of the fugitive dust particle number size distribution ∼2 µm, while the mass distribution mode was ∼7 µm. A comparison of the fugitive dust sampler measurements with those made using standard PM instruments showed that the conventional instruments have a wind-direction bias that can result in under-sampling of large particles. The current measurements suggest that particles suspended from dirt roadways are of importance for local air quality within the near-road environment. Copyright © 2017 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

The paper presents an example of a shared street (woonerf) implemented on low bearing areas as well as the analysis of its technical condition after several years of exploitation. As soon as in the 19th century a previously existing dirt road was used as a shared street on the analysed plot. In a close urban development the area is used as an overflow area during the period of excess precipitation. The execution of the street while taking into account its technical parameters was a challenge for both the designers and the technical services. [ABSTRACT FROM AUTHOR]

Geosynthetics are commonly used in mechanically stabilization of unpaved roads with a low volume of traffic. The practical use of geosynthetics above a weak subgrade or within a base course has demonstrated the benefit of reducing rut depths and prolonging pavement life. The purpose of this paper is to provide design criteria currently available for reinforced unpaved roads. This paper deals with the results of a parametric analysis varying soil and geosynthetic mechanical properties, allowable depth rut and traffic conditions. The focus of the present study is to compare these different design procedures aimed at estimating the base thickness required for reinforced unpaved roads, providing their improvements and limits. Design procedures are also compared with data obtained from field tests. [ABSTRACT FROM AUTHOR]

Two cases were analyzed that involved pitchover/rollover accidents of the same model side by side utility terrain vehicle (UTV). In each case, the UTV ran over a bump on a dirt road and pitched over. The roll cages collapsed, and the drivers suffered significant injuries. Both roll cages collapsed in a similar manner. The design and failure modes of the roll cage structure were analyzed. Engineering analysis included dynamic analysis, laboratory testing, vehicle dynamic testing, finite element analysis, and a review of fundamental mechanical engineering design concepts. Roll cage design and applicable standards were evaluated. Reasonable alternative designs were identified and analyzed. [ABSTRACT FROM AUTHOR]

The author offers observation on the dirt roads in the metropolis of Ann Arbor, Michigan. She reveals how her father described the potholes on Warner Road. The author describes the actions taken by her parents to campaign for the repair of the roads in their neighborhood. She also explains the possible role of climate in the dismal condition of the roads in Michigan.

The paper offers a discussion of the record of human activity in the relief and sediments of a selected lake catchment in Central Pomerania in Poland. One of the basic markers of human activity here is a change in the lake-water level. The dropping level (on average, 1 m/100 years) made it possible for people to develop successively exposed stretches of land along the shore. An analysis of the Polish National Archeological Records and archival maps showed that human development and impact appeared in the lakeshore zone as early as the Neolithic. In Central Pomerania, the changes were especially intensive in the Late Holocene; in the catchment of the lake under study they included a 100% increase in the length of nearby roads. In the archives of its paleoenvironmental data, most traces have been left on farming terraces, while a poorly studied form of record of human activity is a dirt road running parallel to the shoreline. Geodetic and geochemical examination has revealed that the road is a stimulant of change. Its wheeled traffic mixes the accumulated and eroded material, and this causes changes in the shoreline section: the road cutting, which is 2 m wide, deepened, while material accumulates in the form of 0.5-m-wide lateral bars. The compaction of the material brings about changes in the structure of the ground or soil (its density, porosity, compactness, moisture), which affects its level of oxygenation and waterlogging, and, consequently, its iron content. To establish this, a speciation analysis was carried out using the Fe(III)/Fe(II) ratio. It was determined that the lower the ratio, the higher the susceptibility of land to deformation owing to an increase in soil density, a drop in its water capacity, reduction conditions, and the predominance of Fe(II). The research discussed here is only a pilot study, but the authors see extensive opportunities for using speciation analysis in geoarcheology. [ABSTRACT FROM AUTHOR]

Road dust from unpaved roads (dirt roads) is a major source of airborne particulates; the loss of those fines accelerates the deterioration of roads. As a result, road dust emissions are a major concern of the users and managers of dirt roads. Exxon Mobil has been concerned with the dust emissions and rapid road deterioration of the access roads in its natural gas production facility in the Piceance Creek Basin north of Rifle, Colorado. As part of the access road management plan for Exxon Mobil Piceance Creek, a research project was initiated to investigate the effectiveness of several chemical dust suppressants in reducing dust emissions, thus prolonging the intervals between periodic maintenance. Rio Blanco County and the Bureau of Land Management participated in this project. Using the Colorado State University Dustometer and its associated dust measurement protocol, it was found that all chemical suppressants decrease dust emissions and that magnesium chloride () was the most effective dust suppressant under the prevailing weather conditions from March through September, 2010. The fugitive dust emissions from the treated sections of the road were more than four times less than those from the untreated control section, generating less than 0.5 g of dust per 0.8 km (0.5 mi) of test section. It was also found that the native soil road surface type performed better than the new gravel road surface type and that emissions were related to speed. [ABSTRACT FROM AUTHOR]

Off-road vehicles cause long-lasting damage to soils and vegetation, especially under extreme conditions such as those in arid regions. Most research on natural vegetation recovery after dirt-road abandonment has only investigated vegetation in the tracks and not that adjacent to the tracks. We investigated plant expansion into adjacent grassland after its colonization of abandoned tracks in the Mongolian steppe. We surveyed the vegetation around two roads: one abandoned for >4 years and another still in use near the abandoned road. Aboveground biomass and ground cover of each species in and beside the tracks were measured. The dirt roads had sustained relatively low vehicle traffic, so the disturbance of grassland productivity was limited. Vegetation cover and aboveground biomass had almost recovered 4 years after road abandonment. However, a low-palatability clonal herb, Artemisia adamsii, increased in abundance by producing many shoots in and around the abandoned tracks, thereby decreasing the quality of pasture. Our results show that vegetation recovery in tracks of the abandoned road can affect surrounding vegetation through the colonization and expansion of clonal species. Thus, to evaluate natural vegetation recovery after dirt-road abandonment, changes in vegetation not only within but also around abandoned tracks should be investigated. [ABSTRACT FROM AUTHOR]

Entertainment media are a powerful source of cultural influence. Films are especially adept at capturing and preserving for posterity the attitudes, actions, and landscapes of historical events and eras, making them part of cultural memory -- society's shared recollection of past events as depicted in cultural artifacts. Nowhere is this ability better demonstrated than in cinematic portrayals of American agrarian life. In 2001, the Kellogg Institute found Americans recall agricultural landscapes as a sort of pastoral fantasy of rolling green hills, forests, and pristine fields crisscrossed by dirt roads. These images, which constitute Americans' shared cultural memory of agrarian existence, may have been influenced by film portrayals of agriculture. For this study, nine films that met criteria for inclusion of agricultural imagery, cultural significance, and release at least 10 years prior to the Kellogg study were content-analyzed for their visual and thematic adherence to the pastoral fantasy described by Kellogg respondents. Of those films, only two presented agrarian imagery that did not conform to the pastoral fantasy, including depictions of a West Texas cattle ranch at the height of summer and a Midwestern farm muddied by fall harvest. The remaining films contained imagery strongly associated with the pastoral fantasy, indicating they may serve as vehicles for traditional agricultural themes. [ABSTRACT FROM AUTHOR]

The Area of Ecological Interest "Matão de Cosmopolis" is one of the few forest remnants larger than 100 hectares in the metropolitan region of Campinas, São Paulo State, Brazil. Medium and large-sized mammals were surveyed in this forest remnant using natural signs and active search between September 2008 and April 2009. Eighteen species belonging to seven different orders were recorded. Seven species of Order Carnivora were identified, two of which are listed as endangered in São Paulo State (Leopardus pardalis and Puma concolor). Cerdocyon thous, Sapajus nigritus and Canis familiaris had the highest frequency of occurrence. Results show the importance of AEIMC in regional context for mammal conservation. However, immediate actions for its conservation are required due to anthropogenic activities in the area. [ABSTRACT FROM AUTHOR]

Roadkill studies are typically conducted without regard to the carcass permanency time on the highway, which may lead to underestimation of roadkill data, especially small animals that are quickly removed by scavengers. To evaluate the carcass duration time on the lane and its relation to the roadkill time event, we conducted an experiment comparing the removal rate of small carcasses between different stretches of a highway and stretches of dirt roads. The rates found in the study were considered high, with 89 % of carcasses being removed in the first 24 h and 66 % within 12 h. The removals were high for both road categories but reached their peaks at different periods of the day, being higher during the day on the highway and at night on dirt roads. We believe that removal on the highway is dictated by higher vehicular traffic and mainly by the action of scavenger birds during the day, while on dirt roads, it is due to the action of different opportunistic scavengers during the night. [ABSTRACT FROM AUTHOR]

Mongolia, a vast and sparsely populated semi-arid country, has very little formal road infrastructure. Since the 1990s, private ownership and usage of vehicles has been increasing, which has created a web of dirt track corridors due to the communal land tenure and unobstructed terrain, with some of these corridors reaching over 4 km in width. This practice aids wind- and water-aided erosion and desertification, causing enormous negative environmental effects. Little is being done to counter the phenomenon, mainly because the logic of the driving behaviour that causes this dirt road widening is not fully understood. The research in this article postulates that this driving behaviour has rational foundations and is linked to various geographical factors (natural and man-made geographical features). We analysed 11,000 km of arterial routes in the country using spatial statistics and determined that geographically weighted regression (GWR) analysis offers a good explanation for whether, and by how much, the selected geographical factors affect the creation of corridor widths and how their effect varies across the landscape. We determined that corridor widths are correlated to factors such as proximity to river crossings, traffic intensity, and vegetation abundance. Knowing these factors can help local planners and engineers design counter-measures that could help to control and reduce the widths of these corridors, until paved roads can replace the dirt track corridors. [Copyright &y& Elsevier]

L’état d’une route est donné par plusieurs dégradations existantes sur cette dernière. L’on ne saurait analyser isolément chaque dégradation et prendre une décision fiable. Il est question dans cet article de considérer une combinaison de toutes les dégradations les plus récurrentes sur une route en terre à travers une fonction utilité ou encore fonction de décision pour ces dégradations. Chaque dégradation agit en fonction de son importance d’où l’analyse dans ce travail des différents poids à donner à chaque coefficient. Les intrants de cette fonction utilité seront les matrices de dégradation élaborées dans les travaux précédents. Connaissant la valeur de la fonction utilité, le décideur connaît l’action à entreprendre sur un tronçon de route. The deteriorated state of roads is caused by many warring factors. It is not proper to analyse each cause of degradation in isolation. Therefore, this article sets out to study the different combinations of degradations taking into consideration the recurring deterioration of earth roads. With regard to utility function, each degradation reacts according to its importance. It is in this regard that,input of utility function variables are made according to matrices that were developed in previous work. Knowing the value of the utility function, the decision-maker knows what action to take on a stretch of road. [ABSTRACT FROM PUBLISHER]

The article discusses the negative environmental impact of dirt roads in Mongolia in 2012. It says that paved roads have generally been considered to have negative environmental impacts, but paved roads in Mongolia could have benefitted the environment by preventing dirt road creation of vehicle drivers that results in land degradation. It adds that land degradation in dirt roads is the result of its repeated usage that later renders them unsuitable for driving.

Many species of leaf-cutter ants ( Atta and Acromyrmex) increase in abundance following natural or anthropogenic disturbances in the vegetation. However, the mechanisms responsible for such an increase are still poorly understood. We evaluated the effects of nesting site and the availability of palatable forage on survival and growth of Atta laevigata colonies at different developmental stages. Foundress queens transplanted into man-made clearings (dirt roads) had a much higher survival than those transplanted into the adjacent undisturbed savannah vegetation. Similarly, incipient colonies (≥3-months old) had significantly greater survival and growth rates in dirt roads. In contrast, nesting site did not influence performance of young colonies (≥15-months old). Both incipient and young colonies responded strongly and positively to experimental supplementation of palatable forage, and this effect was independent of the nesting habitat. Colonies that received extra food grew faster and had a significantly greater survival rate than control colonies. These results suggest that performance of A. laevigata is affected by the generally greater availability of suitable nesting sites and palatable vegetation in disturbed habitats. This may explain how these ants maintain high densities in these habitats, and since the relative importance of these factors changed with colony ontogeny, our findings highlight the importance of evaluating potential limiting factors throughout the full range of an organism's developmental stages. [ABSTRACT FROM AUTHOR]

Abstract: This study attempts to identify the major factors affecting farm and nonfarm income by using panel data of 894 rural households, interviewed in 2003 and 2005 in rural Uganda. We supplement the panel data with household-level soil fertility data and road distance data to the nearest urban center on three road types: tarmac, loose-surface, and dirt roads. The results suggest that soil fertility, measured by the soil organic matter (SOM) content, is positively associated with crop income but not with livestock and nonfarm income. We also find that the total road distance to the nearest urban center and the road quality have strong negative associations with the crop income. [Copyright &y& Elsevier]

Surface runoff and sediment production on unpaved forest roads in a humid Mediterranean mountainous area has been studied using a simple portable rainfall simulator at an intensity of 90 mm h−1. Thirty six rainfall simulations were carried out on road plots: on the roadbank (12), on the sidecast fill (12), and on the roadbed (12). On the roadbanks, the steady-state runoff coefficient was 85.9% and runoff flow appeared after 63 s on average. On the sidecast fills, the steady-state runoff coefficient was 58.6% and mean time to runoff was 48 s. Finally, on the roadbeds, the steady-state runoff coefficient was 21.5% and mean time to runoff was 41 s. The highest soil loss rate was found on the roadbanks (486.7 g m−2), mainly due to low plant cover, soil texture and rock fragments. The total soil erosion on the roadbanks was 3 and 18 times higher than those from the roadbeds and the sidecast fills, respectively. As a consequence, roadbanks can be considered the main source of sediments on the studied sites, but the function of unpaved forest roads as source points for runoff generation is more important. [Copyright &y& Elsevier]

Abstract: The measurement of soil erosion rates under natural rainfall conditions is costly and time consuming. Data provided by rainfall simulation and static site measurements can be used to predict erosion rates under natural conditions, however the accuracy of this method is largely untested. This is especially true for erosion rates from unsealed forest roads. In this study, the values for a range of erodibility indices calculated from rainfall simulation experiments are compared to observed erodibility index values from 1 year of detailed in-situ erosion monitoring of seven different forest road types. The prediction of phosphorus generation rates from rainfall simulation and/or soil sampling was also evaluated. The results showed that a series of commonly used erodibility indices such as sediment per unit rainfall, sediment per unit runoff, sediment per unit EI 30, and sediment per unit rainfall energy were poorly predicted from the rainfall simulation experiments. Five of the six indices tested substantially overpredicted the observed erodibility at one site, a gravel road subjected to minimal traffic. For the other six road sites predictions were poor and highly variable, the coefficient of efficiency ranging from −13.32 to 0.17 for these erodibility indices. A modified index, the ratio of sediment per unit rainfall energy to the mean rate of rainfall energy input, was able to predict annual erosion rates from six different road surfaces using rainfall simulation data with a coefficient of efficiency of 0.9. The results indicate that existing erodibility indices are not suitable for predicting observed erosion rates on forest roads using rainfall simulation data as collected in this study. It is argued that the modified index is more suited to sites (such as compacted roads) where interrill processes dominate, and erosion rates are less sensitive to peak flows. With respect to nutrient generation rates, rainfall simulation was able to accurately predict the observed proportion by mass of total phosphorus (TP) in runoff with a coefficient of efficiency of 0.96. Direct soil sampling of the road surface could also be used to predict the proportion by mass of TP in runoff. Concentrations of total nitrogen in forest road materials were found to be at the lower detection limit of the laboratory instruments. [Copyright &y& Elsevier]