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61.
This study presents evidence from the Cuyutlàn lagoon, which demonstrates that aquaculture can be socially acceptable, economically viable and environmentally friendly when consideration is first taken of the local circumstances and environment. This evidence was obtained through a user survey, which asked key questions of the local fishing community. These questions aimed to determine the desires and needs of the local community in the context of the local environment. The results from this survey of 56% of the fishing community were presented. The wishes of the fishing community are discussed and a compromise suggested for a sustainable aquaculture for the Cuyutlàn lagoon.  相似文献   
62.

Development of awareness and capacity is a central component to the delivery of ICM and spans from local communities to national-level politicians. Education and training activities associated with ICM must be extremely varied to match both the existing capacity and role that the stakeholders play within the process of ICM. Consequently, there cannot be considered any effective “generic” ICM training; training must be tailored to match the requirements of target groups. The transfer and uptake of good-practice thus becomes an important aspect of quality enhancement in ICM capacity development. Six case studies from the Asia-Pacific region are presented that show diverse and innovative examples of good practice. A comparative analysis of these case studies is carried out in terms of institutional level of impact. In addition a generic systems-based evaluation framework is used to determine the extent to which the training impacts upon ICM implementation indicators. It is concluded that the exchange, transfer, and translation to local conditions of appropriate good practice in ICM capacity development can be an important element in enhancing the impact of ICM programs on the coastal environments and societies. Furthermore, there appears to be a positive link between the involvement of national/state/regional stakeholders in capacity-building initiatives and impacting a wider variety of indicators of ICM delivery.  相似文献   
63.
本文通过辽宁省滨海公路大连市金州北海至葫芦套段七顶山盐场废弃盐滩软基处理的施工,总结了抛石挤淤、堆载预压、强夯置换等软基处理方法在滨海地区软基处理中的综合应用、施工工艺、质量控制手段和质量检验方法。  相似文献   
64.
阐述了南通临海公路混凝土桥梁结构耐久性设计需要从结构用材料的自身特性、混凝土结构的设计和施工质量、桥梁结构所处的环境、构件的使用条件和防护措施等方面考虑。  相似文献   
65.
规划城际铁路台温连接线全长54.95km,连接温州S2线、台州S1线。三线运营组织方式相互关联,对轨道交通整体布局和效能的发挥具有重要影响。采用行车专业设计分析方法,研究了全贯通、部分贯通、独立运营三种行车组织方案。研究结果表明:部分贯通方案兼顾本线、跨线客流,开行跨线大交路和本线小交路列车,但本线两端终点站须进行方案改造。部分贯通方案在工程设计和多元化投资上均留有余地,是较为合理可行的方案。  相似文献   
66.
Both the loggerhead sea turtle (Caretta caretta) and the green turtle (Chelonia mydas) live, feed, and nest in the Mediterranean, mostly on the beaches of Turkey and Greece. The greatest threat to the survival of Caretta caretta has been found to be on the sandy beaches where their lives begin. In this study, the digital terrain model (DTM) of the Iztuzu Beach in Turkey where the Caretta caretta sea turtles lay their eggs was prepared using a global positioning system (GPS) and a geographic information system (GIS). A flexible coastal geographic information system was prepared integrating the DTM with digitally processed satellite images and ground truth of the nesting area and its surroundings. Researchers, decision makers, other end users, or sea turtle experts can find and query any environmental information having a possible impact on the nesting area using a computer-based GIS database. A multidate monitoring of the nesting area allows users to extract and compare much information about the location and condition of the nests and will help researchers develop better strategies for protecting sea turtles.  相似文献   
67.
An assumption underlying the growing support for marine protected areas (MPAs) is that they meet conservation goals and provide economic benefits to fisheries and ecotourism. However, support for MPAs will be at risk if managers cannot assess whether various MPA objectives are being fulfilled. Current approaches to MPA management emphasize the need to evaluate performance criteria; however, there is little consensus on criteria and their evaluation. We propose a marine protected area evaluation model (MPAEM), based on and modified from a multidisciplinary approach used to assess the sustainability of fisheries, called rapid appraisal of fisheries (Rapfish). The application of the MPAEM was explored in a pilot study of 20 MPAs located in different regions of the world. Results indicate that the MPAEM can be used to evaluate MPA management effectiveness. However, the manner in which the evaluation attributes are scored and ways of engaging user groups should be explored before MPAEM can become part of the day-to-day management of MPAs.  相似文献   
68.
Coastal erosion is one of the major coastal problems currently facing Tanzania. Several factors, including sea level rise, geology, and rapid coastal population growth accompanied by rapid increase of human activities that interfere with natural processes, have been linked to the problem. One of the human activities that have been well linked to the problem of coastal erosion is illegal sand mining along beaches, coastal streams/rivers, and other restricted areas. This causes localized accelerated/ severe coastal erosion and enormous environmental degradation and threat to coastal properties. Illegal sand mining is presently a big industry in Tanzania, employing many youths, and has become a social, economical, and environmental problem. Thus, it is a sensitive issue. The problem of illegal sand mining in Tanzania is revisited, and possible measures to control it are proposed. Measures that can help to reduce/eliminate illegal sand mining are: governments to address effectively the problem of unemployment and poverty in the society by formulation of effective policies, including the total liberalization of the labor market and reduction of the tax burden and regulations on potential employers; identifying alternative sources of sand that are environmentally safe to mine, of good quality, and easily accessible; launching well-focused mass education on the problem of coastal erosion; encouraging formation of legally registered associations of sand-miners that will work closely with relevant authorities to curb illegal sand mining; and strengthening of governance and improving research funding in the country.  相似文献   
69.
Satellite images of surface chlorophyll-a concentration measured by the sea-viewing wide field-of-view sensor (SeaWiFS) and of sea surface temperature derived from advanced very high resolution radiometer (AVHRR) measurements, combined with in-situ drifter measurements of surface currents, and ancillary wind, Po River discharge and surface salinity data, are used to describe the surface dynamics in the northern Adriatic during the period September–October 1997.The satellite observations revealed very complex mesoscale dynamics, with time scales of a day or two and length scales of about 10 km, including the meandering and instability of basin-scale currents (e.g., the western coastal layer), jets/filaments and eddies. In addition, the two typical patterns of the Po River plume are observed and qualitatively explained in terms of wind forcing. A basin-wide double gyre pattern spreads the rich runoff water across most of the northern Adriatic from mid-September to early October, following Bora wind events and under stratified sea conditions. In contrast, in late October the Po plume is confined to the coast due to weaker winds and de-stratified conditions. This variability in the Po River plume extension is also confirmed by in-situ salinity measurements.  相似文献   
70.
A data and dynamics driven approach to estimate, decompose, organize and analyze the evolving three-dimensional variability of ocean fields is outlined. Variability refers here to the statistics of the differences between ocean states and a reference state. In general, these statistics evolve in time and space. For a first endeavor, the variability subspace defined by the dominant eigendecomposition of a normalized form of the variability covariance is evolved. A multiscale methodology for its initialization and forecast is outlined. It combines data and primitive equation dynamics within a Monte-Carlo approach.The methodology is applied to part of a multidisciplinary experiment that occurred in Massachusetts Bay in late summer and early fall of 1998. For a 4-day time period, the three-dimensional and multivariate properties of the variability standard deviations and dominant eigenvectors are studied. Two variability patterns are discussed in detail. One relates to a displacement of the Gulf of Maine coastal current offshore from Cape Ann, with the creation of adjacent mesoscale recirculation cells. The other relates to a Bay-wide coastal upwelling mode from Barnstable Harbor to Gloucester in response to strong southerly winds. Snapshots and tendencies of physical fields and trajectories of simulated Lagrangian drifters are employed to diagnose and illustrate the use of the dominant variability covariance. The variability subspace is shown to guide the dynamical analysis of the physical fields. For the stratified conditions, it is found that strong wind events can alter the structures of the buoyancy flow and that circulation features are more variable than previously described, on multiple scales. In several locations, the factors estimated to be important include some or all of the atmospheric and surface pressure forcings, and associated Ekman transports and downwelling/upwelling processes, the Coriolis force, the pressure force, inertia and mixing.  相似文献   
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