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121.
This article summarizes four integrated economic studies undertaken to contribute to resource preservation and restoration decisions for the Peconic Estuary System of Suffolk County, NY. Completed as part of the National Estuary Program, the studies apply distinct resource valuation methods to a wide range of resource issues. The principal goals of this article are to highlight different methodologies that may be used to assess nonmarket economic values in a coastal management context, and characterize differences in the results that one may expect from each approach. We also emphasize potential relationships among values estimated by different nonmarket methodologies, and comment on the implications of these relationships for the interpretation and use of economic value estimates.  相似文献   
122.
Maritime Transportation Systems (MTSs) are essential for world trade; it is crucial to understand how these systems may fail, to be able to maintain their capacity. In this paper, the MTS is seen as a throughput mechanism; a technical system which serves its purpose by moving goods for its dependents. Understanding which key functions and capabilities are prerequisite for the ability to move goods, the loss of which are the failure modes, allows for the creation of a ‘business continuity plan’ for the MTS. Through two surveys and interviews with maritime transportation industry stakeholders, it was observed that while stakeholders in the industry have a solid focus on frequent operational risks, there is a lack of awareness of vulnerabilities, as well as methods for addressing and planning for low-frequency high-impact disruption scenarios. The presented approach provides a structured set of matrices of the key functions of the MTS, allowing stakeholders to increase the system's resilience through preparing to restore this limited number of critical functions.  相似文献   
123.
Beach management and coastal management are interwoven and scale-dependent activities in Australia. Present coastal policies are broad and designed for large, national, and statewide scales. They specify ecologically sustainable development as the overarching goal for coastal management and provide the context for beach management. On smaller scales, an approach focusing on the reduction of geomorphic hazards as the basis of beach management was established by the Coastline Hazard Policy, with nonhazard aspects of beach management such as ecological, economic, and social concerns assuming secondary importance. Although beach management can occur effectively under these coastal management arrangements, better guidance is required to make this process as effective and efficient as possible. This guidance - the policy framework - could be better developed for beach management and better integrated with existing coastal management arrangements. While this policy development is not strictly necessary to achieve positive outcomes from beach management, it is necessary to effectively guide implementation of the existing broad coastal policies. Effective goals for beach management are yet to be thought out and clearly articulated in Australia. A good start would be to couple the present goals of ecologically sustainable development and hazards reduction into a coherent goal for beach management. A specific policy for beaches should be developed given the importance of beaches in Australia.  相似文献   
124.
When China enters the World Trade Organisation (WTO) and becomes more involved in the global economy, her major seaports will be pivotal places where the international shipping and terminal operators interact, conflict and co-operate with the local and the central governments. To demonstrate and understand these interactions, this article analyzes the case of the Yangtze River Delta (YRD), where the competition, co-operation and governance of Shanghai and Ningbo, the two largest ports on Chinese mainland, concern all stakeholders from the central and local governments of China to the container terminal operators and shipping lines overseas.

This paper first develops a conceptual framework for analyzing port development in a regional context. The article then introduces the case of the Shanghai International Shipping Center with a focus on the efforts of the Shanghai Government to establish a regional hub port, which also involves two nearby provinces. This case study reveals the course of the decision-making processes and the power networks currently governing the port development in the YRD. Two domains of port governance are discussed: the role of port authorities in port internal governance, and the crucial influences of local and central governments on the port external governance. It provides evidence that the power of shipping lines and international terminal operators are not as prevalent as in many ports in western countries. It is suggested that the lack of good regional port governance in the region is due to structural problems in administration.  相似文献   
125.
Mapping the water constituents from remotely sensed ocean color data enables a better understanding of the dispersal patterns of river-borne substances in the Gaoping (formerly spelled Kaoping) River, Shelf and Canyon (KPRSC) system. Based on twelve MODIS-Aqua images in the KPRSC region taken in 2005, we apply a newly developed GA-SA approach to derive maps of chlorophyll-a concentration (Chl-a), colored dissolved organic matter (CDOM) and non-algal particle/detritus/mineral (NAP). The results demonstrated that the different characteristics of Chl-a, CDOM and NAP make them ideal tracers for observing large-scale dispersal patterns. With ancillary information of averaged daily precipitation, the daily wind field obtained from QuikSCAT (Quick Scatterometer), and the 8-day composite of the temperature field obtained from MODIS-Aqua, we categorized the surface dispersal patterns as coastal, northwestward and frontal patterns. Also, for the first time, we observed a sudden increase of biomass on a large scale from a pair of ocean color images taken over only a 2-day interval. Another remarkable feature is the interaction between the southeastward flow and the intrusion of the Kuroshio Branch, resulting in complicated patterns with various scales of vortex structures and current fronts. The observed features could be used for model validation of the flow field of the KPRSC system.  相似文献   
126.
On cost-efficiency of the global container shipping network   总被引:1,自引:0,他引:1  
This paper presents a simple formulation in the form of a pipe network for modelling the global container-shipping network. The cost-efficiency and movement-patterns of the current container-shipping network have been investigated using heuristic methods. The model is able to reproduce the overall incomes, costs, and container movement patterns for the industry as well as for the individual shipping lines and ports. It was found that the cost of repositioning empties is 27% of the total world fleet running cost and that overcapacity continues to be a problem. The model is computationally efficient. Implemented in the Java language, it takes one minute to run a full-scale network on a Pentium IV computer.  相似文献   
127.
128.
Based on semistructured interviews (N = 7), informal interviewing (N = 63), and a survey (N = 790), this article describes the cultural models used by mid-Atlantic residents to understand Pfiesteria piscicida. A cultural model is a simplified way of understanding a complex system, shared by members of a culture. Eighty-eight percent of respondents understood Pfiesteria using one of four previously existing cultural models: a disease in fish, a parasite in fish, a water pollutant, and a toxin or poison. These models are not used by marine biologists, who are more likely to refer to Pfiesteria taxonomically or, in its fish killing form, to call it a predator. Our survey shows that the cultural model a respondent holds is correlated significantly with his or her believed pathway of human harm (e.g., eating fish versus swimming) and is correlated significantly but weakly with his or her behavioral responses. We conclude that existing cultural models, as the public has applied them to Pfiesteria, have led people to avoid a range of coastal activities and seafoods, in virtually all cases unnecessarily. Cultural models appear to explain public reaction better than previously hypothesized factors such as inaccurate media coverage. These findings suggest an approach to developing a pedagogical and communications strategy which could provide the public with a cultural model better matched to Pfiesteria.  相似文献   
129.
Large temporal and spatial data series are increasingly available and easy to produce. This paper uses Zipf analysis to evaluate serial data sets from the HOTS, BATS, EquaPac and high-resolution vertical profiles of FluoroMAP. Zipf analysis produced Zipf exponents from best-fit lines that permitted comparison among data sets. It allows comparison of one-dimensional series despite differences in scale and missing data. Zipf exponents ranged from 0.043 to 0.83. Serial data with sampling intervals of milliseconds and months showed exponents that ranged around 0.3. To the extent that Zipf exponents measure structure and variation, the indication is that structure of distributions is similar over millimeters and hundreds of kilometers. Zipf analysis provides a means to quantify similarities and differences, and suggests that variation is linked across many length scales for phytoplankton.  相似文献   
130.
Towards a seascape typology. I. Zipf versus Pareto laws   总被引:1,自引:0,他引:1  
Two data analysis methods, referred to as the Zipf and Pareto methods, initially introduced in economics and linguistics two centuries ago and subsequently used in a wide range of fields (word frequency in languages and literature, human demographics, finance, city formation, genomics and physics), are described and proposed here as a potential tool to classify space–time patterns in marine ecology. The aim of this paper is, first, to present the theoretical bases of Zipf and Pareto laws, and to demonstrate that they are strictly equivalent. In that way, we provide a one-to-one correspondence between their characteristic exponents and argue that the choice of technique is a matter of convenience. Second, we argue that the appeal of this technique is that it is assumption-free for the distribution of the data and regularity of sampling interval, as well as being extremely easy to implement. Finally, in order to allow marine ecologists to identify and classify any structure in their data sets, we provide a step by step overview of the characteristic shapes expected for Zipf's law for the cases of randomness, power law behavior, power law behavior contaminated by internal and external noise, and competing power laws illustrated on the basis of typical ecological situations such as mixing processes involving non-interacting and interacting species, phytoplankton growth processes and differential grazing by zooplankton.  相似文献   
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