How does isolation affect the economic activity of cities? Transport costs are widely considered an important barrier to local economic activity but their impact in developing countries is not well-studied. This paper investigates the role of intercity transport costs in determining the income of sub-Saharan African cities. In particular, focusing on fifteen countries whose largest city is a po...

CONTEXT Anthropogenic vectors enhance the natural dispersal capacity of plant seeds significantly in terms of quantity and distance. Human-mediated seed dispersal (i.e. anthropochory) greatly increases the dispersal of crop species across agroecosystems. In the case of oilseed rape (OSR), spillage of seeds from grain trailers during harvest has never been quantified. METHODS Our experimental ...

BACKGROUND There is widespread public concern that exposure to road vehicle traffic pollution causes asthma, but epidemiological studies in developed countries have not generally confirmed a strong effect and may have underestimated the risk as a result of relatively high and widespread exposure to traffic in everyday life. AIMS To investigate the effect of living close to a traffic bearing r...

Previous studies showed that the likelihood of a bear becoming a nuisance and thus being removed from a population (i.e., relocated or killed) depends on numerous factors such as natural food supply, sex, age, and reproductive status. Distances from a bear’s home range and activity centers to confl ict zones such as towns, roads, and trails used by humans also aff ect the incidence of nuisance ...

This paper describes a simple method for estimating haul road defect positions from alongside roads. It is a method that is cheap and easy to implement, needing only a minimal amount of field equipment and training. Observers are required to estimate the bearing and distance to a defect, and to record their location using a GPS receiver. All further processing is automated and can be done entir...

Roads form vast, pervasive and growing networks across the Earth, causing negative environmental impacts that spill out into a ‘road-effect zone’. Previous research has estimated regional global extent of these zones using arbitrary distances, ignoring spatial distribution distance-dependent attenuation different forms road impact. With Great Britain as study area, we used mapping roads realist...

An improved hierarchical fuzzy inference method based on C-measure map-matching algorithm is proposed in this paper, in which the C-measure represents the certainty or probability of the vehicle traveling on the actual road. A strategy is firstly introduced to use historical positioning information to employ curve-curve matching between vehicle trajectories and shapes of candidate roads. It imp...

This paper investigates the effect of four driving forces, including elevation, slope, distance to drainage and distance to major roads, on urban expansion in five Saudi Arabian cities: Riyadh, Jeddah, Makkah, Al-Taif and Eastern Area. The prediction of urban probabilities in the selected cities based on the four driving forces is generated using a logistic regression model for two time periods...

Methods This analysis uses GIS to determine a numeric value between 1 and 100 for an undeveloped land parcel’s relative risk for development and reduction in water quality. The analysis includes parcels in the Town of Standish that are within a 5km radius of the PWD intake pipes and within 1km of the lake shore. The development risk is calculated for each undeveloped parcel that is not currentl...