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排序方式: 共有207条查询结果,搜索用时 15 毫秒
91.
92.
植被护坡作为一种有效兼顾生态环境保护及边坡治理的护坡技术,在工程实践中得到了广泛的推广和应用。然而植被护坡技术的研究成果却滞后于工程应用。文章结合国内外对于植物根系加筋土剪切试验的成果,根据试验土样及方法的不同,将植物根系加筋土试验分为原状根系加筋土直接剪切试验、原状根系加筋土三轴剪切试验、重塑根系加筋土三轴剪切试验以及重塑加筋土直接剪切试验等四类,分别介绍了上述试验的试验方法、试验工况,并总结分析了根系对于土体抗剪强度的增强作用、根系加筋土强度在各工况组合下的变化规律,指出了存在的问题及后续开展研究的方向,以期为后续植物根系加筋土剪切试验的开展提供一定的参考。 相似文献
93.
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
94.
三维植被网路基边坡防护工艺 总被引:6,自引:0,他引:6
三维立体植被网作为一种塑料新型的坡面防护材料问世,它具有较好的使用性能和推广价值,本文中突出介绍了其结构特点及施工工艺等内容。 相似文献
95.
96.
介绍了沧州地区沿海环境基本状况,从结构设计、防腐混凝土、防腐涂层等方面对桥梁防腐采取对策,对防腐混凝土、防腐涂层提出施工要求,通过综合措施达到桥梁混凝土耐久性要求。 相似文献
97.
Desiderius C. P. Masalu 《Coastal management》2013,41(4):347-359
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
98.
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
99.
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
100.
Rodney J. James 《Coastal management》2013,41(2):149-160
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