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1.
加入WTO对中国旅游业的影响及应对措施   总被引:1,自引:0,他引:1  
加入WTO必然对中国旅游业的发展产生重大影响,既包括创造机遇,也包括提出挑战。对此,应采取加快体制改革、留住高素质的旅游经营管理与服务人才、积极学习和借鉴国际旅游业先进的经营管理模式和经验、适时调整旅游业的产业对策,宣传中华民族文化、抓住奥运旅游的机遇,创造中国旅游的新品牌等应对措施,使得中国旅游业步入按国际惯例办事的轨道。  相似文献   

2.
资源评估是应用各种统计和数学方法量化地于业种群形态对渔业管理选择的反应。资源评估不仅仅是预测静止的最佳捕捞努力量和持续产量,而是评估鱼类和渔民对管理决策和其它变化的动态反应。在动态的渔业系统中帮助管理者进行决策是一个困难的任务,资源评估生物学家要配合管理者和决策者提出适当的问题,和思考渔业对变化的动态反应。  相似文献   

3.
Abstract. When the Isthmus of Panama emerged as a land bridge, it set the stage for allopatric speciation in the marine fauna. In the present study Pacific and Atlantic populations of three cognate pairs of crabs were used to discern whether physiological divergence has occurred as a result of exposure to different thermal regimes in habitats and in the putative absence of gene flow. Additional comparison was made with Belize and Florida populations of the Atlantic Panama cognate. This was done to test the strength of correlation between physiological divergence and exposure to different thermal regimes in populations that potentially form a common genetic pool. Water temperatures decrease periodically in Pacific Panama and Florida but not in Atlantic Panama or Belize. Physiological divergence in volume and ion regulation was assessed in response to repeated exposure to either control and decreased temperature or to control and increased temperature. Results indicate that exposure to naturally occurring decreased temperatures in habitats has resulted in divergence. This divergence is demonstrated both in enhanced ability to regulate volume at decreased temperature and impaired ability to regulate volume at elevated temperature.  相似文献   

4.
夏季南海上层环流动力机制的数值研究   总被引:10,自引:0,他引:10  
通过利用一个分区性的正压-斜压衔接模式来探讨夏季南海的上层环流特征及其动力机制,结果表明:夏季期间,由于风生环流的不稳定性促使在东沙群岛附近的气旋涡的强度及位置发生变化,并间接导致黑潮侵入南海北部的程度变化以及气旋涡南侧的反气旋式环流、西沙群岛西南侧的气旋涡的强度和范围出现波动现象;在南海南部的北向西边界流由于离岸的西南季风所驱动在中南半岛中部沿岸脱离岸线往东北方向的流动,导致沿岸的水体大量流失而在沿岸形成一支南向补偿流并在西沙群岛西南侧诱生一气旋涡,而上述的离岸西边界流则作顺时针方向流动,从而在南海南部形成反气旋式大环流;在南沙海槽附近出现的局地气旋涡和万安滩附近的气旋涡分别受β效应、底形效应的作用而形成.  相似文献   

5.
G. Najafian   《Ocean Engineering》2007,34(17-18):2289-2299
Offshore structures are exposed to random wave loading in the ocean environment and hence the probability distribution of their response to wave loading is a minimum requirement for efficient probabilistic analysis of these structures. Due to nonlinearity of Morison wave loading and also due to intermittency of wave loading on members in the splash zone, the response is often non-Gaussian. Part I of this paper was devoted to the development and validation of a new probability model for drag-only responses (i.e. responses due to the drag component of Morison wave loading). This part is devoted to the development and validation of new probability models for both inertia-only and total responses.  相似文献   

6.
基于WebGIS的海洋科学数据共享平台的分析与设计   总被引:4,自引:1,他引:3  
根据国家自然科学基金委青岛海洋科学资料共享服务中心建设的实际情况,从需求分析、系统结构设计、数据建模以及实现技术等几个方面,详细介绍了基于WebGIS的海洋科学数据共享平台建设的思路和方法。在建设过程中,采用用户界面层、业务逻辑层、数据库层的三层架构模式进行系统软件设计,提高了系统的可维护性;运用组件技术进行编码,实现了代码的封装性和可复用性;采用关系型数据库和Netcdf格式相结合来进行数据的存取,解决了海洋数据结构复杂、格式不统一的问题,使查询变得更为方便;利用IDL和ION技术来开发WebGIS,实现了电子海图的漫游、数据查询以及数据统计结果输出。  相似文献   

7.
亚洲海域鲎的种类和分布   总被引:2,自引:0,他引:2  
审核有关亚洲海域鲎种类和分布的历史文献发现,亚洲海域只有圆尾鲎Carcinoscorpius rotundicauda、中国鲎Tachypleus tridentatus和南方鲎Tachypleus gigas3种鲎分布。圆尾鲎分布于中国香港、北部湾、雷州湾以南、印度尼西亚爪哇岛北岸以北、菲律宾南部以西和恒河河口印度东北部以东的海域。中国鲎分布于长江口以南的中国海域、日本濑户内海、九州岛北岸以南、印度尼西亚爪哇岛北岸以北、苏门答腊岛印度洋侧以东和苏拉威西岛以西的海域。南方鲎分布于越南西贡以南、爪哇岛北岸以北、菲律宾南部以西的太平洋海域及印度恒河印度东北部以东的印度洋海域。以前有关中国北部湾海域和香港海域有南方鲎的报道是错误的,把中国鲎的幼体及成体误当成了南方鲎。中国海域只有中国鲎和圆尾鲎2种鲎分布。中国的海南、广西、广东西部和香港(可能还包括台湾)等是圆尾鲎分布的海域。其沿岸要严禁食鲎,以防误食圆尾鲎而引起河豚毒素中毒。  相似文献   

8.
Increasing numbers of people are living in and using coastal areas. Combined with the presence of pervasive coastal threats, such as flooding and erosion, this is having widespread impacts on coastal populations, infrastructure and ecosystems. For the right adaptive strategies to be adopted, and planning decisions to be made, rigorous evaluation of the available options is required. This evaluation hinges on the availability and use of suitable datasets. For knowledge to be derived from coastal datasets, such data needs to be combined and analysed in an effective manner. This paper reviews a wide range of literature relating to data-driven approaches to coastal risk evaluation, revealing how limitations have been imposed on many of these methods, due to restrictions in computing power and access to data. The rapidly emerging field of ‘Big Data’ can help overcome many of these hurdles. ‘Big Data’ involves powerful computer infrastructures, enabling storage, processing and real-time analysis of large volumes and varieties of data, in a fast and reliable manner. Through consideration of examples of how ‘Big Data’ technologies are being applied to fields related to coastal risk, it becomes apparent that geospatial Big Data solutions hold clear potential to improve the process of risk based decision making on the coast. ‘Big Data’ does not provide a stand-alone solution to the issues and gaps outlined in this paper, yet these technological methods hold the potential to optimise data-driven approaches, enabling robust risk profiles to be generated for coastal regions.  相似文献   

9.
The effects on ethoxyresorufin O-deethylase (EROD), NADPH-cytochrome c reductase and NADH cytochrorne b5 reductase activities of digestive gland in Meretrix meretrix exposed to tributyltin (TBT) at environmental levels (0.1,1.0,10.0 ng/dm as stannum concentration),in experimental condition, were evaluated. The EROD, NADH cytochrorne b5 reductase activities were significantly inhibited after exposure to 10.0 ng/dm^3 TBT for 8 and 20 d, the NADPH cytochrorne c reductase activities were significantly inhibited after exposure to 0.1,1.0 and 10.0 ng/dm TBT for 8 d and to 1.0 and 10.0 ng/dm for 20 d, as compared with the matched control, while NADH cytochrorne b5 reductases and NADPH cytochrome c reductase activities were induced after exposure to 10.0 ng/dm^3 TBT for 2 d. The EROD activity in the 10 ng/dm^3 group,and the NADH cytochrome b5 reductases activities in 1.0 and 10.0 ng/dm groups, were significantly induced when transferred to clean recovery tanks for 7 d. The three enzymic activities in the clams exposed to TBT were recovered to the level corresponding to that of the control group after transfer to clean recovery tanks for 20 d. NADPH cytochrome c reductase activity in Meretrix meretrix seems to be more sensitive to exposure of TBT than that of the EROD and NADH cytochrome b5 reductases. The results suggest that induction and inhibition by TBT to the monooxygenase system enzymic activity in Meretrix meretrix would simultaneously exist. The enzymic activities were inhibited by exposure for a long time. The results suggest that inhibition of the monooxygenase system should be an indication of the exposure to environmentally relevant concentrations of TBT for a long time.  相似文献   

10.
Climate change is altering many environmental parameters of coastal waters and open oceans, leading to substantial present-day and projected changes in the distribution, abundance and phenology of marine species. Attempts to assess how each species might respond to climate change can be data-, resource- and time-intensive. Moreover, in many regions of the world, including South Africa, species may be of vital socioeconomic or ecological importance though critical gaps may exist in our basic biological or ecological knowledge of the species. Here, we adapt and apply a trait-based sensitivity assessment for the key marine species in the southern Benguela system to estimate their potential relative sensitivity to the impacts of climate change. For our analysis, 40 priority species were selected based on their socioeconomic, ecological and/or recreational importance in the system. An extensive literature review and consultation with experts was undertaken concerning each species to gather information on their life history, habitat use and potential stressors. Fourteen attributes were used to estimate the selected species’ sensitivity and capacity to respond to climate change. A score ranging from low to high sensitivity was given for each attribute, based on the available information. Similarly, a score was assigned to the type and quality of information used to score each particular attribute, allowing an assessment of data-quality inputs for each species. The analysis identified the white steenbras Lithognathus lithognathus, soupfin shark Galeorhinus galeus, St Joseph Callorhinchus capensis and abalone Haliotis midae as potentially the most sensitive species to climate-change impacts in the southern Benguela system. There were data gaps for larval dispersal and settlement and metamorphosis cues for most of the evaluated species. Our results can be used by resource managers to determine the type of monitoring, intervention and planning that may be required to best respond to climate change, given the limited resources and significant knowledge gaps in many cases.  相似文献   

11.
An eco-hydrodynamic model was used to estimate the carrying capacity of pollutant loads and response of water quality to environmental change in Yeoja Bay, Korea. An energy-system model also was used to simulate the fluctuation in nutrients and organic matter in the bordering wetland. Most water quality factors showed a pulsed pattern, and the concentrations of nutrients and organic matter of seawater increased when input loads of nutrients increased due to freshwater discharge. The well-developed tidal zones and wetlands in the northern area of the bay were highly sensitive to input loads. Residence times of water, chemical oxygen demand (COD), and dissolved inorganic nitrogen (DIN) within the bay were estimated to be about 16 days, 43.2 days, and 50.2 days, respectively. Water quality reacted more sensitively to the effects of nitrogen and phosphorus input than to COD. A plan to reduce the present levels of COD and dissolved inorganic phosphorus (DIP) by 20–30% and DIN by at least 50% in pollutant loads is needed for satisfying the target water quality criteria. The natural removal rate of nutrients in wetlands by reeds was assessed to be approximately 10%.  相似文献   

12.
The need for a statutory framework to manage valuable marine resources in the United States is highlighted by problems such as fragmented ocean governance and increasing conflict over the use of ocean spaces. On July 19, 2010 President Obama signed Executive Order 13547 to create a National Ocean Policy (NOP) for the United States. A subsequent Implementation Plan, released in 2013, set up hundreds of actions to be accomplished between 2013 and 2025 to address economic, community, scientific and other issues. Progress implementing the NOP appears to have stalled. The purpose of this paper is to give an overview of the NOP and its Implementation Plan, and then discuss what needs to be done to bring the vision it set forth to fruition.  相似文献   

13.
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.  相似文献   

14.
—Most terminals for tankers are piers and sea islands,while other types include single pointmoorings and multiple-buoy moorings.The LNG and LPG carrier moored to the jetty is a very commonterminal for transfer of gas in open seas.It is important to estimate the motions and line tensions of theLNG carrier when it moors to a jetty in metocean environment.Normally,the motions of the LNG carrierwould be restricted by the loading arm,which is connected to LNG carrier's manifold.An example of125,000m~3 LNG carrier moored to a jetty exposed to a set of environment conditions is given.Amathematical model which is based on the equations of motion in the time domain is used to the analysisof LNG moored to an offshore jetty exposed to waves,swell,wind and current.By means of a time do-main computer program TERMSIM computations are carried out to determine and optimize the lay-outand/or orientation of the jetty and mooring gear in terms of forces in mooring lines and fenders and theenvelope of motions of the loadi  相似文献   

15.
A data-driven model has been developed to analyse the long-term evolution of a sandbank system and to make ensemble predictions in a period of 8 years. The method uses a combination of empirical orthogonal function (EOF) analysis, (to define spatial and temporal patterns of variability), jack-knife resampling, (to generate an ensemble of EOFs), a causal auto-regression technique, (to extrapolate the temporal eigenfunctions), and straightforward statistical analysis of the resulting ensemble of predictions to determine a ‘forecast’ and associated uncertainty. The methodology has been applied to a very demanding site which includes a curved shoreline and a group of mobile nearshore sandbanks. The site is on the eastern coast of the UK and includes the Great Yarmouth sandbanks and neighbouring shoreline. A sequence of 33 high quality historical survey charts reaching back to 1848 have been used to analyse the patterns and to predict morphological evolution of the sandbank system. The forecasts demonstrate an improved skill relative to an assumption of persistence, but suffer in locations where there are propagating features in the morphology that are not well-described by EOFs.  相似文献   

16.
Guifang Xue 《Marine Policy》2006,30(6):651-658
The paper discusses China's policy adjustment responding to flag state responsibilities of the Fish Stocks Agreement and the Compliance Agreement. China's incorporation and application of the management measures of the two instruments into its domestic legislations regarding distant water fishing vessels is examined to illustrate China's compliance as a flag state. It will be shown that China has taken concrete steps to bring its management practice in line with the requirements of international fisheries instruments and has endeavoured to respond to the two instruments positively. However, China needs to set priorities to improve its overall management capacity so as to make it ready to ratify the two instruments and to live up to their terms.  相似文献   

17.
Development of ocean community systems relating to the Taiwan Strait Tunnel (TST) project, with regionalization and multistage approach is proposed. The purposes of these systems are to assist the development of coastal marine lands and harbor facilities and to develop connecting isolated islands into an organized community by means of embankment roadways, tunnels, bridges, ferryboats, and so on. The major aim of such an approach is to develop the isolated abandoned islands into useful land improvement, expand the forest, agriculture, and fishing industries and other resources to generate additional revenue to subsidize some of the cost for building the TST. This article points out the systems' importance, outlines the general procedures, and discusses a possible transportation network connecting islands with land; and the outlines development of the knowledge-based expert system computer program to be applied to the ocean community systems relating to the TST project.  相似文献   

18.
东海PN断面夏季温盐及化学要素的分布特征   总被引:9,自引:2,他引:9  
刘兴泉 《海洋与湖沼》2001,32(2):204-212
由东海PN断面夏季温鼻度及化学要素CTD资料分析表明,东海夏季的温跃层和盐跃层在次表层生成,其强度随着跃层自陆架坡折区至近岸和外海的上移逐渐减弱。陆架区近表层的温度和盐度呈垂直均匀分布,冲绳海槽次表层呈高温、高盐,近表层呈高温,近表层呈高温、低盐,底层呈低温、次高盐特征。溶解氧浓度自近岸到外海由低变高,表层至底层溶解氧浓度在陆架区由高变低,冲绳海槽区则先由低变高然后又由变低。总二氧化碳浓度自表层至底层和自陆架坡折区到近岸和外海由低变高。磷酸盐和硅酸盐浓度自近岸至外海由高变低,而自表层至底层由低变高。陆架区的近表层和陆架坡折区分别有一个高碱度区。温盐及化学要素的分布特征与夏季海区垂直环流的反气旋运动、长江冲淡水及黑潮水入侵和海面强热辐射有关。此外,化学要素分布还与夏季海区的温盐结构、表混合层与大气间二氧化碳气体交换及表混合层中碳和营养盐光合作用的利用有关。  相似文献   

19.
水产养殖病害及其药物控制与水产品安全   总被引:9,自引:0,他引:9  
针对目前我国水产养殖过程中对发生的病害多采用药物控制极易造成因药物使用不当或盲目用药等原因,使细菌产生耐药性、水产品中出现药物残留、养殖环境不断恶化的同时,最终会影响食品安全的现状。从常见病毒病、细菌病,以及寄生虫病等论述开展对药物残留毒性研究,重视专用渔药研制、加强用药指导,减少用药盲目性等工作的重要性。  相似文献   

20.
浙江省为远洋渔业大省,但远洋渔业产业结构不均衡,过洋渔业有进一步的发展潜力。文章介绍浙江省过洋渔业发展现状,分析目前浙江省在亚洲、南美洲、非洲和大洋洲主要入渔国的资源状况和发展前景,从面临的挑战和有利的条件进一步分析浙江省过洋渔业的发展形势。在此基础上,结合当前国家远洋渔业政策,提出浙江省过洋渔业的发展建议,包括统一思想认识,转变发展方式;强化政策支持,解决发展短板;调整捕捞作业结构,促进平衡发展;鼓励兼并重组,培育现代规模企业;加快渔船建造和改造,提升渔船现代化水平;加强制度建设,保障健康发展;明确安全职责,促进合法合规生产;加大科技投入,加强科技支撑;从严培训教育,提高从业人员素质;发挥行业协会作用,强化行业自律。  相似文献   

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