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1.
Abstract

Policymakers and analysts concerned with coastal issues often need economic value information to evaluate policies that affect beach recreation. This paper presents economic values associated with beach recreation in San Diego County generated from a recreation demand model that explains a beach user's choice of which beach to visit. These include estimates of the economic values of a beach day, beach closures, and beach amenities.  相似文献   

2.
Coastal erosion threatens many sandy beaches and the ecological, economic, social and cultural amenities they provide. The problem is especially chronic in South Florida. A frequent solution for beach restoration involves sand replacement, or nourishment, but is temporary, expensive, and has usually been funded by governmental sources. However, as such agencies reduce their share and require more local funding, beach nourishment must rely on other funding sources, including beach recreationists. Our study characterized three South Florida beaches and probed visitor willingness-to-pay for beach nourishment. We found that even beaches within close proximity attract different user types. Users are amenable to higher fees if they lead to greater resource protection.  相似文献   

3.
付博新  刘林 《水运工程》2016,(10):50-56
南太武海滩前部水域浪小流弱,九龙江和近岸陆域排洪排污对海滩直接影响较大,造成严重的沙滩泥化和环境问题。面对复杂的外部边界条件,综合海岸动力学、生态学、环境学等多学科的方法,统筹城市排洪排污需求和景观生态需要,分析沙滩泥化的现状和机理,从技术、经济和生态方面论证了治理方案的可行性,并创新性探索减淤屏在整治海滩泥化工程设计中的应用。  相似文献   

4.
A real-time beach hazard level associated with nearshore hydrodynamics is presented in this article. The suitability of the discussed alert system is illustrated via its application to fifteen beaches in the Balearic Islands (Western Mediterranean Sea) providing nearshore safety conditions for beach safety manager. The system provides daily forecasts of nearshore wave conditions using the deep water wave forecasts. The shallow water wave data (wave height, period, and direction) together with the morphology of the site (presence of bars, capes, beach type, etc.) are used to define a hazard level (low, medium, and high) associated with local conditions. The resulting hazard level is transmitted via SMS to lifeguards and local authorities for real-time beach management. The low computational cost of this system after the initial implementation and subsequent calibration results in a very suitable approach for beach management in order to mitigate risks related to local hydrodynamics.  相似文献   

5.
近年来,在航道整治工程中采用了一种外形类似"Y"的整治建筑物,取得了较好的护滩效果。选取长江下游典型潮汐分汊河段——白茆沙河段进行地形概化,采用潮流数学模型研究Y形建筑物的护滩效果。结果表明,护滩堤一般就近布置在需守护的滩体前沿等深线附近,护滩堤长度需覆盖滩体迎流面最宽处,护滩堤高程可取潮汐分汊河段特征水位;头部潜堤一般沿滩脊线布置,长度延伸至需守护的低滩,可根据多年历史地形资料选择在滩体稳定的等深线附近,高程则以可满足整治建筑物结构安全即可。  相似文献   

6.
Beach closure policies in the United States suffers from two shortcomings. Type I errors, in which clean beaches are closed, results when managers resort to extensive beach closures because they are unsure of the spatial extent of water contamination. Type II errors, in which contaminated beaches remain open, occur because the time from sampling to public notification can be between two and nine days. Coastal Ocean Observing Systems (COOS) could reduce the impact of both Type I and II errors. The COOS could reduce the spatial extent of beach closures by better predicting the fate of contaminants in coastal waters. An improved COOS also could reduce the time from sampling to public notification of contamination events. I estimate the lost recreational value associated with Type I errors (unnecessary closures) and the public health costs associated with Type II errors (unnecessary exposure to waterborne illnesses) for beaches in Southern California.  相似文献   

7.
Beach “nourishment” consists of placing sand on an eroding beach. The widened beach provides increased storm protection to adjacent structures and improved recreational benefits, but is most often transient, requiring on-going, repeated nourishment episodes. Numerical models of beach nourishment typically address such questions as how long a widened beach will last; economic models compare the benefits and costs of preserving a stretch of beach without regard to its geomorphic evolution. Neither have addressed the physical nor economic interactions between adjacent nourishing communities. Here, we couple a numerical model of coastline evolution and a cost-benefit model of beach nourishment, allowing adjacent communities to make dynamic nourishment decisions. Beach nourishment benefits adjacent communities both “updrift” and “downdrift.” The total amount of money spent on nourishment activities can decrease by as much as 25% when adjacent communities both conduct on-going nourishment projects, as opposed to the case where each community nourishes in isolation.  相似文献   

8.
Fecal contamination of coastal waters has led local public health agencies to issue tens of thousands of beach advisories annually and to advise against ocean swimming and surfing for 72 hours following a rain. The responsiveness of recreationists to beach advisories and the “72 hour rule” is estimated by merging four years of multi-daily surfer and beachgoer counts at one beach in Southern California with hourly data on beach advisories, recent precipitation, meteorological conditions, and the UCSB academic calendar. Both surfing and beach-going decreased significantly following rainfall in response to the 72 hour rule, showing that recreationists are willing to engage in health risk-reducing avoiding behavior. However, neither surfing nor beach-going decreased significantly during beach advisories. Surfers were significantly more responsive to beach advisories during dry periods than during wet periods, consistent with the hypothesis that recreationists are most likely to respond to a risk warning that they believe provides accurate and additional health risk information beyond what they can observe personally. Additional studies of beach advisories elsewhere could clarify whether responsiveness to beach advisories varies by recreationist demographic, recreational activity, frequency of advisories, or frequency of repeat visitation. Increasing the accuracy and additional information provided by beach advisories, as proposed by numerous authors, could lead to increased responsiveness.  相似文献   

9.
文中重点就目前海洋污染事故存在的风险、交通运输部门针对船舶污染应急体系建设所做的工作、当前海洋污染事故应急瓜机制存在的问题以及对如何完善海洋污染事故应急反应机制等作思索和探讨。  相似文献   

10.
Using data collected from May 1978 to November 1996, this article assesses the effects of fluctuating water levels on the beach and shoreline at the Northeast Beach, Point Pelee, Lake Erie, Canada. To compare the serial dynamics of lake levels with net shoreline positional changes and beach net sediment flux, the data are transformed to standard scores to deal with the differences in the units and in the scale associated with each variable. The results demonstrate that over the 18-year period, fluctuating lake levels are associated with shifts in shoreline position and the development of various aggradational and degradational states at the beach. A sustained rapid rise in lake levels will initiate an erosional sequence which will persist even with declining water levels. With a persistent decline in water levels the beach and shoreline will adjust very gradually from unstable, erosional states to an aggradational state. Other results emphasize that those beach sectors directly governed by artificial structures suffered disproportionately higher erosion during high-water levels. Coastal managers must, therefore, be cognizant of the fact that shore protection devices must be carefully designed in order to be effective against the influence of fluctuating lake levels.  相似文献   

11.
文中对最近13年间在上海港发生的船舶污染事故进行归类分析,指出上海港可能发生船舶污染事故的主要风险源,并针对这些船舶污染风险源,提出防范和应对措施,以期防止上海港船舶污染事故的发生。  相似文献   

12.
This article presents a comprehensive analysis of beach management in the Catalan coast (NW Mediterranean) by introducing and integrating results from different partial projects. They analyzed the legal, political, and administrative framework of beach management, the quality tools available, the practices of management, the processes of beach use, and beach waste/litter dynamics. The information obtained served to create a new beach management tool referred to as the Beach Quality Index, which was developed by an interdisciplinary team of academics from the natural/physical sciences and social sciences that worked together during the course of four years. Information obtained from users and key stakeholders served to create the index. The study demonstrated that as a consequence of the shortcomings in the legal and administrative system as well as inadequate practices of beach managers, beach management in the area experiences coordination problems, insufficient information and lack of proactive management, pollution, and in general problems associated with the satisfaction of short-term user demands.  相似文献   

13.
汪生杰  胡殿才 《水运工程》2012,(12):194-199
近年来冀东油田为满足滩海油藏勘探开发需要,成功建造了一系列海上人工岛.工程海域属粉砂质海岸,浅滩、深槽、沙脊交错分布,海域地形条件复杂.工程处于外海且无掩护,风浪流较大,冬季受冰冻影响且冰荷载大.滩海油藏勘探开发用人工岛,安全环保要求苛刻.这对人工岛的设计提出了较高的要求.对冀东油田人工岛设计关键技术进行总结分析,包括人工岛功能、选址、平面布置、建设标准、保滩护底措施、围堤结构、岛域吹填及地基处理、对外交通码头等人工岛设计所涉及的主要方面,可供同类工程参考.  相似文献   

14.
陈飞  郑力  蔡大富  曾方 《水运工程》2012,(10):81-86
航道整治工程中护滩带的水毁现象较为突出,基于实际工程中的破坏现象,分析了护滩带破坏的主要影响因素,对护滩带进行受力分析,初步探讨了护滩带水毁机理,提出了多种解决措施,并在其他工程中进行了试验性的运用,通过运用后的效果对比,提出了较为成熟的护滩带结构形式。  相似文献   

15.
肖政  蒋昌波  夏波 《水道港口》2007,28(1):16-19
罗斗沙岛位于琼州海峡东侧,近年由于风暴潮、波浪水流的作用,岛屿西北侧发生严重侵蚀,通过分析罗斗沙岛屿附近的水文、地质和泥沙运动特性,对罗斗沙岛屿附近岸滩演变的原因进行了分析,并对今后演变趋势进行了预测。  相似文献   

16.
“胜丰”轮于1997年8月20日0200被97-11号强台风带来的狂风巨浪从日照港锚地冲上沙滩,造成罕见的高位搁浅事故。我们采用多种技术手段,使该轮安全出浅,完成救助工程  相似文献   

17.
Coastal areas are among the most biologically rich regions in the world. They provide tremendous benefit to people through ecological services like pollution filtration, carbon sequestration, and storm protection. However, human activity has decreased the ability of ecosystems to provide these services, and in many coastal areas, restoration is not as effective as it could be. Limited success is largely attributed to vague goals and a lack of holistic, science-informed planning. Quantifying coastal habitat health can aid in setting better restoration goals and lead to greater restoration success. The Long Island Sound Study National Estuary Program conducted the first comprehensive look at coastal habitat health for the Long Island Sound Estuary. In this study we also reviewed landscape-scale habitat assessment progress within other coastal programs. Results can be applied to establish ecosystem health-oriented goals that improve habitat function and resilience across coastal areas.  相似文献   

18.
Beaches along the eastern branch of the Giens double tombolo are subject to coastal erosion. Prediction of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the concept of equilibrium beach profile(EBP) could be useful in finding the most suitable measure to address the erosion problem. Field investigation data of 11 beaches along the eastern tombolo were supplied for this study, and a nonlinear fitting technique was applied to estimate the best parameter values of seven empirical formulations of the relevant EBP. All of the observed beach profiles could be described by a single function, but a single EBP was inadequate to represent all of the beach profiles observed. The variation found could be explained in terms of longshore variation of bathymetry, sediment size, and wave parameters. Analysis of the validity of the EBPs revealed that a representative EBP of each beach is governed by different equilibrium parameters.  相似文献   

19.
Abstract

In southern Rhode Island, there is growing concern that housing and recreational demands will soon overwhelm the capacity of the coastal salt ponds to absorb wastes, produce seafood, and maintain scenic qualities. As a result, coastal towns have been studying the feasibility of using land controls such as downzoning to protect these coastal amenities. The paper presents an economic analysis of the downzoning program proposed in the town of South Kingstown. Hedonic price and contingent valuation methods are used to value coastal amenities. The estimated net present value of “swimmable” water is shown to be $3.1 million.  相似文献   

20.
Beaches along the eastern branch of the Giens double tombolo are subject to coastal erosion. Prediction of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the concept of equilibrium beach profile (EBP) could be useful in finding the most suitable measure to address the erosion problem. Field investigation data of 11 beaches along the eastern tombolo were supplied for this study, and a nonlinear fitting technique was applied to estimate the best parameter values of seven empirical formulations of the relevant EBP. All of the observed beach profiles could be described by a single function, but a single EBP was inadequate to represent all of the beach profiles observed. The variation found could be explained in terms of longshore variation of bathymetry, sediment size, and wave parameters. Analysis of the validity of the EBPs revealed that a representative EBP of each beach is governed by different equilibrium parameters.  相似文献   

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