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111.
112.
Although the success of marine protected areas (MPAs) and associated zoning schemes is largely dependent on stakeholder acceptance and support, there have been relatively few studies examining the response of recreational stakeholders to MPA proposals. This study investigates the response of recreational boaters to a proposed MPA in British Columbia, Canada. Using a structured questionnaire (n = 543) and a focus group (n = 6), the research examines the level of support for the concept of marine zoning and identifies key factors influencing support or opposition. Results indicate that a small majority of recreational boaters support the concept of marine zoning, but that there are areas of concern that ought to be addressed as MPA implementation proceeds. Support for zoning was strongly related to perceived benefits, particularly environmental benefits. Furthermore, perceived benefits overall were found to outweigh concerns as determinants of recreational boater support for zoning. Major dimensions of opposition included perceptions of over-regulation, loss of access for boating, and mistrust of the government. A suggestion is that such concerns may be mitigated through focused communication and meaningful involvement of boaters in the zoning process.  相似文献   
113.
The Bay Conservation and Development Commission (BCDC), has designated a number of shoreline sites around San Francisco Bay for exclusive use of water‐related industry. This is intended both to reduce future needs for Bay fill, and to reserve those waterfront sites needed for long‐term industrial growth. The Commission currently defines water‐related industries as those “requiring”; a shoreline site for water transportation. The Commission is now considering the use of an economic criterion for identifying water dependency. This involves comparisons of the uniquely water‐related benefits and costs to the firm to locate on the shoreline, as opposed to its location at an inland site. By limiting use of deepwater sites to those industries that are significantly water‐dependent under this criterion, long‐term economic efficiency is served, and the need for future Bay fill for industrial growth is reduced. The data and analysis required to implement an economic water‐dependency criterion do not appear to be a barrier to use of such a test in the regulatory process. Whereas water dependency is an important concern to BCDC, other factors, including environmental constraints, must also be weighed when evaluating industrial projects.  相似文献   
114.
Abstract

Corals and coral communities provide substantial societal benefits by virtue of their recreational and esthetic appeal, the habitat provided for commercially harvested fish and shellfish, the structural foundation provided for productive coastal ecosystems, and the market value of harvested coral specimens. Coral resources are subject to adverse effects from pollution, dredging, specimen collecting, anchor damage, commercial fishing, overharvesting, and activities related to offshore petroleum development. Management programs which protect coral resources in the United States comprise a patchwork of separate federal and state programs. They attempt to adapt broad regulatory authorities for parks, fisheries, offshore mineral resources, and other subjects for the purpose of coral conservation. These programs embody species‐specific, area‐specific, and generic approaches to coral management. This paper traces the evolution of U.S. coral management programs and comments on their respective strengths and weaknesses. Alternative approaches for strengthening management systems could include new coordinating committees, legislation, memoranda of agreement between involved agencies, and others.  相似文献   
115.
Abstract

A territorial sea comprising 6.7 million acres of offshore lands extending three geographic miles into the Atlantic Ocean three marine leagues (nine geographic miles) into the Gulf of Mexico makes Florida the second largest “oceanowning”; state in the contiguous United States. Florida's history, climate, economic development, and worldwide reputation have evolved from the state's relationship with the sea. The state is now becoming aware that aggressive management of its ocean resources is necessary to preserve the future of that relationship. The purpose of this article is to present some of Florida's recent legal and policy initiatives that have been directed toward better understanding and management of ocean resources and uses.  相似文献   
116.
Two-dimensional and three-dimensional Green-Naghdi (GN) models equipped with a numerical wave-absorbing beach have been developed to simulate nonlinear, regular, and irregular wave propagation. The numerical beach is introduced near the downstream boundary to absorb outgoing waves. An appropriate amount of numerical damping and an appropriate length of numerical beach are investigated using numerical experiments. The results show that the GN models with a numerical beach work very well in simulating wave propagation in water in a small computational domain.  相似文献   
117.
At Terra Nova Bay, the scallop Adamussium colbecki (Smith, 1902) characterises the soft and hard bottoms from 20 to 80 m depth, constituting large beds and reaching high values of density (50–60 individuals/m2) and biomass (120 g/m2 DW soft tissues). To assess its role in the organic matter recycling in the coastal ecosystem, its filtering and biodeposition rates were evaluated in laboratory experiments during the austral summer 1993/94. Filtration rates, measured in a flow-through system, were calculated from the difference in particulate organic carbon (POC), nitrogen (PON) and chlorophyll-a (Chl-a) concentration in inflow and outflow water. Experiments were performed using natural sea water with POC, PON and Chl-a concentrations of about 450 μg/l, 90 μg/l and 2 μg/l, respectively. The biodeposition rate and the biochemical composition of the biodeposits were studied in order to detect how the organic matter is transformed through feeding activity of A. colbecki. At +1°C temperature, the average filtering rate was about 1 l h−1 g−1 (DW soft tissues) in specimens ranging in body mass from 2 to 3 g (DW soft tissues) and 6–7 cm long. The biodeposition rate in 3–8 cm long specimens, ranging from 0.4 to 5.7 g (DW soft tissues), was about 5.65 mg DW/g DW/day, leading to an estimate of Corg flux, through biodeposition by A. colbecki, of about 21 mg C m−2 day−1 at in situ conditions. Comparison between the biochemical composition of seston and biodeposits shows a decrease of the labile compounds, of the Chl-a/phaeopigments ratio in the biodeposits. The recorded C/N ratio decrease suggests a microbial colonisation in the biodeposits. This study suggests that Adamussium colbecki plays an important role in coupling the material fluxes from the water column to the sea bed, processing about 14% of total Carbon flux from the water column to the sediments, with an assimilation efficiency of 36%.  相似文献   
118.
为了阐述20世纪除汽车机动性外,交通发展经历的最重要的进程——城市高速公路的出现,考察了过去100年来美国城市交通规划的历史。通过回顾各种研究资料,认为资助州际公路发展所采用的方法使联邦和州公路工程师成为主管,这影响了公路的选线及设计。联邦公路工程师只关注机动车通过效率的最大化,而在很大程度上忽略了城市的其他利害关系。没有先进的规划理念指导、过度建设、稀疏、放射环状的道路网对于加强机动性取得了极大的效益,但通常要为此付出巨大的社会和环境成本。最后指出,在实践中要重新审视具有百年历史的协调交通与土地利用规划的观点,而且,公共财政权宜之计式的政治决策方式将对工程、出行和城市形态产生深远的影响。·  相似文献   
119.
著名的莆田祥应庙前身是当地白杜方氏家族专用的祠堂.庙里供奉的神灵显惠侯,当地的百姓把他视为农业生产及生命财产的保护神,同时,他也是航海者信奉的神灵.本文作者以周尾和朱纺这两人出海之前均到该庙膜拜的典型事例,分析指出上述二人的出海经商与白杜方氏家族存在着直接关系,可能是受雇于当时既从事农业又涉猎海上贸易的白杜方氏家族,因此宋时显惠侯只是一个地方性的神灵,只对某一部分人提供某些特定的庇护,并不具有普遍意义.  相似文献   
120.
Objective To map a mouse deafness gene.identify the underlying mutation and develop a mouse model for human deafncss.Methods Genetic lindage cross and genome scan wer used to map a novel mutation named hypoplasia of the membranous labyrinth (hml),which causes hearing loss in mutant mice.Results ① hml was mapped on mouse Chr 10 (~43 cM from the centromere) suggests that the homologous human gene is on 12q22--q24, which was defined on the basis of known mouse-human homologies (OMIM,2004). ② This study has generated 25 polymorphic microsateUite markers, placed 3 known human genes in the correct order in a high-resolution mouse map and narrowed the hml candidate gene region to a 500 kb area.  相似文献   
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