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41.
以青岛市为例,通过因子分析法从10个指标中选取影响沿海地区海洋生态环境承载力动态变化的3个主因子,将其归为二方面的因素,第一主因子为人口和经济因素,第二主因子和第三主因子为海洋环境污染因素.依据这3个主因子的因子得分,用熵值法进行赋权,计算了1998~2005年青岛市海洋生态环境承载力的综合得分,进而得出,虽然青岛市海洋生态环境承载力的两大主要压力(人口和经济)逐年增长,但其仍朝良好的方向发展,并对引起这一结果的主要原因进行了解释,从而为海洋生态环境承载力的定量化计算提供了理论依据,对沿海地区的海洋生态环境管理有重要意义.  相似文献   
42.
在分析青岛市旅游发展现状的基础上,选取生物多样性、旅游资源丰富度等共27个因子,构建区域旅游生态环境的评价体系,运用模糊数学方法和AHP法对各层指标进行权重计算,最后建立生态因数模型对青岛市所辖12个区市的旅游生态环境进行评价。结果表明:青岛市所辖区市可划分为四级旅游生态环境可持续发展程度类型区;在诸多评价因子中,以区域经济环境对旅游生态环境的贡献值最大,其次为生态环境各项因子。  相似文献   
43.
国家级新区具有产城融合发展的示范作用,这种示范作用是否达到政策预期是值得探讨的。研究基于产城相互作用机制,构建了产城融合指标体系,运用熵值法、耦合协调度模型对舟山群岛新区和西海岸新区两个地区2014—2018年产业发展与城市功能的发展水平,以及两者之间的协调度进行了测度和分析。结果发现:①两新区初期均呈现出不同程度的不平衡状况,但整体趋于良性发展。②后期两区在一定程度上实现了产城融合,不过发展空间仍然较大。③两新区由于发展条件不一,呈现出不同的发展态势。鉴于此,国家级新区在推进城市产城融合时应遵循因地制宜的原则,及时根据新区的发展现状采取相应的发展调控策略。  相似文献   
44.
青岛市中水回用研究   总被引:2,自引:0,他引:2  
青岛是一个水资源严重短缺的城市,研究中水回用对缓解青岛用水紧张和节约水资源都有积极的意义.研究了青岛市中水回用的必要性、可行性及现状,进而提出了推进青岛中水回用的有关对策.  相似文献   
45.
Reports on Gulf War illness (GWI) implicated the use of the pesticide permethrin (PER), and the insect repellent N,N-diethyl-m-toluamide (DEET), in its etiology, as well as pyridostigmine bromide (PB), which was given as a prophylactic treatment against nerve agent exposure. Using Affymetrix microarrays the genomic response of human neuronal SHSY-5Y cells to 10 days of exposure to these agents was characterized and profiles of gene modulation unique to each treatment were demonstrated. In particular, a significantly greater impact of PER was observed compared to the other treatments. The Ingenuity Pathway Analysis knowledgebase was used to analyze the genomic datasets and attribute functional consequences to the effects of related genes, which were significantly up- or down-regulated in response to different treatments. Canonical pathways shown to be significantly modulated at the genomic level in response to exposure included cellular mechanisms, which might contribute to the clinical presentation in GWI patients and thus be targeted for further investigation as potential targets for therapeutic intervention.  相似文献   
46.
We analysed fisheries trends in the northern region of the Gulf of California, within the Biosphere Reserve of the Upper Gulf of California and Colorado Delta River and the Vaquita Refuge Area, and suggest measures to protect the vaquita, Phocoena sinus. We compiled and analysed catch reports of artisanal fishermen in the three fishing communities of the Upper Gulf of California (San Felipe in the State of Baja California, and Golfo de Santa Clara and Puerto Peñasco in the State of Sonora) from 1995 to 2007. This information was categorised with respect to geographic information systems, and all fishing sites within two marine protected areas in the region were identified. In addition, from a survey based on direct interviews with artisanal fishermen in each of the three ports, we identified that 23% of fishermen will continue fishing despite on-going fishing buy-out programmes in the region. We suggest several specific courses of action to decrease the fishing impact on this critically endangered cetacean. However, given the critical situation of this critically endangered species, it is very uncertain whether enforcing a no-take zone within the biosphere reserve and the Vaquita Refuge Area, or even a wider fishing moratorium, will be enough to save this endangered species from extinction.  相似文献   
47.
为了更好地利用青岛崂山区地下空间资源,在全面分析该区地形、地质、水文等条件的基础上,结合岩土工程勘察原始数据和现场水样调查分析报告,根据模糊数学理论和专家经验,遴选出地形地貌、地质构造、工程地质、水文地质、洪水淹没、人口密集程度为评价因子并确定各因子的权重,研究构建了该区地下空间利用评价模型。将评价模型与GIS相结合,利用ArcGIS强大的空间分析功能,采用定量分析的方法得到地下空间利用适宜性分区。研究表明青岛崂山区地下空间建设适宜区面积为106.1km^2,占评价区域面积的73.8%;一般区域面积为26.5km^2,占评价区域面积的18.4%;不适宜区域面积为11.14km^2,占评价区域面积的7.8%。  相似文献   
48.
Coastal areas of Iran are heavily affected by urbanisation, industrialisation, and maritime activities. One consequence of this environmental pressure is the contaminants accumulation, as heavy metals, into the marine ecosystem. In this review, the coastal areas in the north and south of the country were assessed for lead (Pb) contamination of, one of the most toxic metals found in the environment. All studies conducted during 2006–2016 with at least 10 specimens that reported the mean and standard deviation of Pb were considered in this review. Heterogeneity between studies was assessed using the Q and I2 statistics. The Pb mean concentration overall studies was estimated to be 21.88?µg/g (95% CIs: 16.25–27.50). Random effect model showed no statistical difference in mean Pb concentration levels between south and north coasts. However, the variability in Pb mean concentrations within southern coasts was considerable and statistically significant. Moreover, the Pb concentrations in the northern coasts of Persian Gulf and Oman Sea, in south of Iran, decreased in the following order Hormozgan > Khuzestan > Sistan-VA-Balluchestan > Bushehr while in the southern coasts of Caspian Sea, in north of Iran, decreased in the order Guilan > Mazandaran > Golestan.  相似文献   
49.
The export of wetland-derived materials to the coastal ocean (i.e., the “Outwelling” hypothesis) has received considerable attention over the past several decades. While a number of studies have shown that estuaries export appreciable amounts of nutrients and carbon, few studies have attempted to estimate the importance of estuarine sources for the coastal carbon budgets in river-dominated coastal ecosystems. A novel tidal prism model was developed to examine estuarine-shelf exchanges in the Barataria estuary, a deltaic estuary located in the north-central Gulf of Mexico. This estuary has been the site of a massive wetland loss, and it has been hypothesized that carbon export from the eroding coastal wetlands supports the development of a large hypoxic zone in the coastal Gulf of Mexico. The model results show that the Barataria estuary receives nitrogen through the tidal passes and releases carbon to the coastal ocean. The mean calculated tidal water discharge of 6930 m3 s−1 is equivalent to about 43% of the lower Mississippi River discharge. The annual total organic carbon (TOC) export is 109 million kg, or 57 gC m2 yr−1 when prorated to the total water area of the estuary. This carbon export is equivalent to a loss of 0.5 m of wetland soil horizon over an area of 8.4 km2, and accounts for about 34% of the observed annual wetland loss in the estuary between 1978 and 2000. Compared to the lower Mississippi River, the Barataria estuary appears to be a very small source of TOC for the northern Gulf of Mexico (2.7% of riverine TOC), and is unlikely to have a significant influence on the development of the Gulf's hypoxia.  相似文献   
50.
液压爬模在泰州大桥南塔施工中的安全控制   总被引:2,自引:0,他引:2  
液压爬模具备自动爬升、操作简便、作业人员少、施工效率高、外观质量好等优点,其施工工艺和技术也比较成熟,在不少大中型工程建设项目中得到广泛应用。液压爬模的操作平台和爬升系统为一整体,液压驱动装置能实现整体均匀爬升,其安全性能有了明显提高。但液压爬模结构复杂且体积庞大,其安装、调位和脱模以及模板的收分等操作和使用环节的安全风险很大,容易出现模板坍塌、高处坠落、物体打击等事故,是施工中安全控制的重点。泰州大桥南塔工程引进了液压自动爬模系统来进行塔身浇注施工,施工中的安全控制措施取得了良好的效果。本研究将以泰州大桥南塔工程为背景,对液压爬模在塔柱施工过程中的危害因素进行分析并提出相应的控制措施,可供类似工程借鉴。  相似文献   
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