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791.
J. Foster-Smith A. C. Birchenough CEFAS S. M. Evans J. Prince 《Coastal management》2013,41(2-3):181-194
There are concerns that Cable Beach, which is of outstanding natural beauty and a major tourist attraction for Broome and the Kimberley region of northwest Australia, is suffering damage from recreational use, particularly that caused by off-road vehicles. To assess current levels of human impact on the shore and its fauna, the southern-most kilometer of the Beach, covering an area to which vehicles had access and an adjacent area closed to vehicles, was surveyed for human usage and shore crab abundance. Human usage over the recording period was high in the area with high vehicular access. The amount of litter, although considerable, was well below that recorded in some other tourist destinations elsewhere in the world. Burrows of both the ghost crabs Ocypode spp, and the sand bubbler, Scopimera inflata, were less numerous in areas of high vehicle use than those of low use. Both species may be valuable in monitoring human impacts on Cable Beach. 相似文献
792.
Anthony T.H. Chin Joyce M.W. Low 《Transportation Research Part D: Transport and Environment》2010,15(8):483-488
Atmospheric and water pollution are two main sources of negative environmental externalities generated by shipping. This study recognizes the negative externalities in the production of port services in East Asia by explicitly incorporating environmental impacts of shipping. Programming techniques are used to analyze 156 Origin–Destination pairs between 13 major East Asian ports, to derive the externality-augmented measures of port productivity and efficiency at the waterside. The results suggest that the inclusion of externality mitigation strategies can exert a considerable influence on efficiency performance. 相似文献
793.
This paper deals with the lane assignment problem in the Automated Highway Systems (AHS). The purpose of lane assignment strategies
is to increase throughput on multi-lane highways with many entry and exit points, based on the itineraries of vehicles using
the highway (point of entry, time of entry and exit point) and the effects of maneuvers. Using partitioned lane assignment
strategies, the lane assignment problem is formulated as an optimization problem to find the proper positions of partitions.
Then the optimal problem is solved using a Genetic Algorithm (GA). The proposed algorithm has been validated by comparing
its solution with that of an all-cases algorithm for a simple case. Moreover, a traffic simulator with a realistic car-following
model as well as lane change logic has been developed. The simulation results show the efficiency of the proposed genetic
algorithm, compared with random assignment algorithms. 相似文献
794.
An assessment of the rationale for the vertical disintegration of ship management suggests that there might be compelling economic benefits for the separation of ownership from management. In this context, as a means for developing effective marketing strategies, it is important for ship managers to know the criteria used by current and prospective clients for ship manager selection and evaluation. The aim of this paper is to empirically identify the dimensions for ship manager selection and performance evaluation and their relative importance and to discuss the implications for marketing emanating from such an assessment. The methodology adopted includes the collection of secondary and primary data, both from ship managers and their clients, using interviews and a mail survey. The results indicate the prevailing importance of certain dimensions in selection (e.g. technical ability, reputation, competency) and evaluation (responsiveness, trustworthiness, technical ability), whereas it also found that price alone is not perceived to be as important in ship manager selection. It is concluded that placing emphasis on such dimensions in the formulation of a marketing strategy will contribute towards the attraction and retention of clients, whereas cost-cutting measures to allow price reduction, as well as advertising, will be ineffective over the long term. 相似文献
795.
796.
The twin forces of rising affluence and population are altering coastal communities around the world. High amenity, environmentally sensitive areas—particularly attractive, non-metropolitan coastal environments—are witnessing a tidal wave of in migration from former urbanites. As a result, these communities are struggling to accommodate growing numbers of people with urban tastes and rural dreams in areas with governance structures and physical infrastructure designed for occasional tourists. This article looks at how governance frameworks in coastal Australia respond to the profound environmental, social, and cultural implications of this process. We offer a typology of non-metropolitan coastal growth settings—from exurban contexts to isolated coastal hamlets—and identify the main environmental, social, economic, and governance issues they face. We then outline the policy and legislative framework governing coastal areas in Australia and show how this framework is interpreted at the local level through an analysis of five local plans covering different coastal settings. 相似文献
797.
798.
Jon Grant Cedric Bacher Peter J. Cranford Thomas Guyondet Michel Carreau 《Journal of Marine Systems》2008,73(1-2):155-168
A fully-coupled biological–physical–chemical model of a coastal ecosystem was constructed to examine the impact of suspended mussel culture on phytoplankton biomass in Tracadie Bay, Prince Edward Island, Canada. Due to the extent of mussel culture there, we hypothesised that shellfish filtration would control the concentration and distribution of phytoplankton and other suspended particles in the bay. Circulation was delineated with a tidally-driven 2D numerical model and used to drive an ecosystem model with a focus on pelagic components including phytoplankton production, nutrients, detritus, and mussels. The benthos were treated as a sink. Nutrients and seston were forced by tidal exchange and river input, with phytoplankton additionally forced by light. Boundary conditions of seston and nutrients were derived from field studies with an emphasis on the contrast between spring (high river nutrients, low temperature) and summer (low river inputs and high temperatures). Model output was used to map phytoplankton carbon over the bay for each season and in the presence of mussels and river nutrient input. Results indicate severe depletion effects of mussel culture on overall phytoplankton biomass, but no spatial pattern that can be attributed to grazing alone. Primary production generated by nutrient-rich river water created a mid-bay spike in phytoplankton that dominated the spatial pattern of chlorophyll-based carbon. Model results were validated with surveys from a towed sensor array (Acrobat) that confirmed the river influence and indicated bay-wide depletion of 29% between high and low water. Our model results indicate that the farm-scale depletion emphasised in previous studies cannot simply be extrapolated to seston limitation at the ecosystem level. 相似文献
799.
Ki-Hyun Kim Sudhir Kumar Pandey Hang Thi Nguyen Soo-Yeoun Chung S.-J. Cho M.-Y. Kim J.-M. Oh Young Sunwoo 《Transportation Research Part D: Transport and Environment》2010,15(3):168-174
The concentrations of particulate matter, PM2.5, PM10, and TSP at an urban roadside and an urban background station are analyzed. Data collected over a 10 year period are analyzed. The concentrations of the particulates measured at the urban site are systematically larger than at the background station. The mean PM values at the former also exhibit a slight fall over the decade unlike those at the background station. Overall, the particulate matters at both locations are in an intermediate range of global level, e.g., approximately two times lower than those in other Asian regions but higher than in Europe. 相似文献
800.
Christian Hofer Martin E. Dresner Robert J. Windle 《Transportation Research Part D: Transport and Environment》2010,15(1):37-45
This study investigates how air traffic emissions taxes may impact carbon emissions in the US. The magnitude of emissions savings in the US domestic airline industry that would result from lower demand for air travel as taxes are levied and air fares increase is estimated. At the same time, the air-automobile substitution effect is considered and it is argued that some air travelers may divert to automobiles, thus increasing automobile carbon emissions. Both the analysis of the aggregate US domestic airline industry and the study of a sample of US domestic route markets indicate that potentially sizeable increases in automobile traffic and related emissions may substantially reduce the environmental benefits of air travel carbon emissions taxes. In some instances, carbon emissions may even increase in short-haul markets. Sensitivity analyses are performed to demonstrate the robustness of these findings. 相似文献