Labour market effects in assessing the costs and benefits of road pricing

Traffic congestion and the policies used to combat it have been studied extensively. One area which has received less attention is the secondary impacts of such policies. This paper uses a micro-simulation framework to study the effect on labour markets of road pricing. The key benefit of our chosen methodology is that it allows a simultaneous consideration of both commuting and migration decisions. We show that while welfare gains can be achieved through optimal charging, this may come at the price of decreased integration. This may manifest through either greater centralisation tendencies in population, or through unemployment disparities between regions.     

The Impacts of Recreational Four-Wheel Driving on the Abundance of the Ghost Crab (Ocypode cordimanus) on a Subtropical Sandy Beach in SE Queensland

There is increasing concern regarding the impacts of recreational four-wheel driving (4WDing) on sandy beach environments. The ghost crab Ocypode cordimanus is a widely distributed Australian species that utilizes beaches and dunes for constructing burrows and for foraging. Comparisons of ghost crab abundances (using burrow counts) in areas “open” and “closed” to recreational 4WDing were conducted on exposed sandy beaches on North Stradbroke Island, off the coast of southeast Queensland. Beaches where recreational 4WD activity is present had significantly lower ghost crab abundances than beaches where it is absent. The most plausible reason for this difference in abundance is that ghost crabs are highly vulnerable to being crushed by beach traffic when feeding on the beach at night. To mitigate the impacts of recreational 4WDing on ghost crab population management intervention is needed. Possible changes to the management of recreational 4WD activity include the setting aside of areas free of recreational 4WD activity for the conservation of biodiversity, or a prohibition on driving on the beaches between dusk and dawn. There is also a need for a consistent and transparent approach in Queensland for quantifying and monitoring 4WD activity in sandy beach environments.     

Aspects of the European Maritime Industry

This article discusses the regulatory and operational issues which have recently confronted a number of U.S. ports as a result of their dredging programmers. It describes the environmental concerns which have led community groups to raise legal objections to the traditional practice of ocean dumping of dredged material, the federal/state regulatory framework within which these objections have been considered and recent legislative changes to that framework. The paper describes in some detail the specific case of the Port of New York and New Jersey, which has experienced severe delays in its dredging programme since 1992 (and a resulting loss of business) as well mounting costs for dredged material disposal. The paper concludes that, complicated as the technical problems involving dredged material disposal may be, it is the political and economic issues involved which are likely to be decisive in the eventual outcomes for affected ports.     

Demand Information from Incomplete Data—Application to Commercial Catfish

This paper provides general background information relating to the physical characteristics and operations of the Suez Canal. In connection with the future development of the Canal, the research programme currently being undertaken by a British consortium is outlined, with particular reference to the traffic system presently operating.     

A model to design a national high-speed rail network for freight distribution

High-speed rail is often touted as a means to reduce congestion on the United States’ highways by removing passenger car traffic. But highway congestion can also be reduced by reducing the amount of freight traffic. So, given the advances in high-speed rail, the potential exists for developing a national high-speed network for freight distribution. To design such a network considering highway traffic and transit times, we present an uncapacitated network design model with a post-processing step for the capacity constraint. To illustrate how our modeling approach could be used by policy makers to evaluate the impacts of a high-speed rail network, we apply our models with preliminary data on high-speed rail operating parameters for freight applications and from current data on shipments from a major truckload carrier and the US Census Bureau.     

Identification and assessment of aquatic resources for power plant sites on Maryland's Eastern shore

Abstract

A power plant siting procedure which accounts for the protection and preservation of aquatic resources, defined as sensitive life forms and life stages of economically valuable species of finfish and shellfish, is presented as it was executed on Maryland's Eastern Shore. Negative effects of power plant development and operation are generated principally by the cooling water intake and discharge system. The site‐selection procedure is thus presented as a two‐faceted process, termed regional screening, requiring the separate but simultaneous identification of land‐based sites and cooling systems. Criteria included in regional screening for cooling systems reflected life‐sustaining processes essential to the maintenance of aquatic resources. Major sources of effects of power plants on aquatic resources and siting principles as they affect aquatic resources are defined. Information‐gathering techniques included extensive interviews with key research scientists, state personnel, and numerous Chesapeake Bay watermen.     

The opinions and attitudes of Louisiana's Coastal Zone residents toward outdoor recreational development: A perspective for planning and management

Abstract

In 1967, a new road facilitated access to a number of small, impoverished, rural communities in a marshy region along Mexico's Pacific coast. One of these—the only one situated on the Pacific shore—began to be visited by an increasing stream of tourists. This article discusses the severe sociocultural problems which the initial phase of tourism development caused in Teacapán, and argues that these are part of a syndrome which is manifest in similar situations worldwide. By anticipating this syndrome before tourism development gets underway, planners and managers of coastal tourism development in Third World nations would be better prepared to mitigate most of its severe effects.     

产能扩张带来质量隐患

从2009年中国取代美国成为世界上最大的汽车市场以来,汽车制造商已然进入了一场激烈的扩张竞赛。在过去两年里,数万亿元人民币涌入汽车制造行业。汽车制造商开始疯狂地扩大产能。按照这种扩张速度,中国的汽车年产能到201 3年将增至31 00万辆,达到2009年产能的两倍。而在中国开展业务的国际汽车制造商则显得保守一些。过去四年里,在占据全国乘用车一半产量的情况下,     

Nature and/or nurture? Analyzing the determinants of transit ridership across US urbanized areas

Public subsidy of transit services has increased dramatically in recent years, with little effect on overall ridership. Quite obviously, a clear understanding of the factors influencing transit ridership is central to decisions on investments in and the pricing and deployment of transit services. Yet the literature about the causes of transit use is quite spotty; most previous aggregate analyses of transit ridership have examined just one or a few systems, have not included many of the external, control variables thought to influence transit use, and have not addressed the simultaneous relationship between transit service supply and consumption. This study addresses each of these shortcomings by (1) conducting a cross-sectional analysis of transit use in 265 US urbanized areas, (2) testing dozens of variables measuring regional geography, metropolitan economy, population characteristics, auto/highway system characteristics, and transit system characteristics, and (3) constructing two-stage simultaneous equation regression models to account for simultaneity between transit service supply and consumption. We find that most of the variation in transit ridership among urbanized areas – in both absolute and relative terms – can be explained by factors outside of the control of public transit systems: (1) regional geography (specifically, area of urbanization, population, population density, and regional location in the US), (2) metropolitan economy (specifically, personal/household income), (3) population characteristics (specifically, the percent college students, recent immigrants, and Democratic voters in the population), and (4) auto/highway system characteristics (specifically, the percent carless households and non-transit/non-SOV trips, including commuting via carpools, walking, biking, etc.). While these external factors clearly go a long way toward determining the overall level of transit use in an urbanized area, we find that transit policies do make a significant difference. The observed range in both fares and service frequency in our sample could account for at least a doubling (or halving) of transit use in a given urbanized area. Controlling for the fact that public transit use is strongly correlated with urbanized area size, about 26% of the observed variance in per capita transit patronage across US urbanized areas is explained in the models presented here by service frequency and fare levels. The observed influence of these two factors is consistent with both the literature and intuition: frequent service draws passengers, and high fares drive them away.