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1.
基于多目标决策模型的如东近岸浅滩适宜围填规模研究   总被引:2,自引:0,他引:2  
适宜的围填海规模能够最大限度的协调岸滩围填和海洋资源环境保护的关系。以江苏辐射沙脊海域如东近岸浅滩围填海为例,运用多目标决策理论与方法,综合考虑围填海对动力泥沙环境、海洋生态环境、资源综合开发和社会经济影响,建立围填海适宜规模评价指标体系,构建适宜围填规模评价决策模型。并对该岸段不同的围填规模方案进行计算,据此推荐围堤前沿线位于+5 m的围填海方案是该岸段的适宜围填规模。对围填海适宜规模的研究手段和方法进行了探索和尝试。提出的研究方法及推荐的如东岸段近岸浅滩适宜围填规模可为江苏滩涂资源的开发提供参考。  相似文献   

2.
围填海生态环境效应评价方法研究   总被引:2,自引:0,他引:2  
分析了围填海对海洋生态系统的影响,构建了包括生物效应、生态系统功能效应和环境效应三方面的围填海生态环境效应评价指标体系,初步提出了各指标评价标准的确定方法;建立了层次分析法与赋值综合评价法相结合的围填海生态环境效应综合评价模型,为客观评价围填海生态环境效应提供科学依据。应用该方法实例评价大连市庄河海域围填海生态环境效应,结果表明该海域围填海造成生态环境效应影响严重,应该严格控制该海域围填海工程。  相似文献   

3.
基于可持续发展角度,运用环境经济学理论和方法,建立效益和费用评估模型.按照生态系统服务理论将围填海造成的生态损失货币化,作为经济成本的一部分,参与围填海方案经济效益评价.本文对罗源湾多个围填海方案进行综合评价,并对其进行排序,寻求适宜方案.  相似文献   

4.
针对围填海不同规模方案的选择问题,目前已有很多文献建立了评价指标体系,然而利用数学算法进行评价研究的还比较少。文章以现存的评价指标体系和专家评分为基础,利用语言层次分析法(LAHP)来计算各个评价指标的权重,并采用多属性决策方法——逼近理想点法(TOPSIS)对不同规模的围填海方案进行排序,从而选出最优方案。进一步用实际的例子,说明了利用LAHP-TOPSIS方法进行方案排序的步骤,给出了评价结果。结果显示:文章提出的评价方法能够为沿海及港口城市围填海方案提供有效的评价工具,对于围填海规模方案选择具有重要意义。  相似文献   

5.
围填海工程平面设计评价方法探讨   总被引:1,自引:0,他引:1  
以盘锦辽滨沿海经济区区域建设用海规划和长兴岛临港工业区区域建设用海规划为应用示范案例,开展了围填海工程平面设计评价方法的应用示范研究。结果表明,本研究建立的围填海工程平面设计评价方法体系具有较广泛的适用性和实用性,可以指导和促进我国围填海工程平面设计向离岸式、岛群式、组团式方向发展。盘锦辽滨沿海经济区区域建设用海规划围填海工程平面设计综合评价数值达到0.88,属于Ⅴ等级,平面设计优秀。长兴岛临港工业区区域建设用海规划围填海工程平面设计综合评价值0.68,属于Ⅳ等级,平面设计优良。  相似文献   

6.
依据珊瑚礁生物海岸的资源和生态特点,通过分析识别近岸围填海对珊瑚礁生态影响的主要因子和生态服务功能的影响,构建珊瑚礁生物海岸围填海适宜性的评价指标体系,选取珊瑚礁资源、环境、生态和经济为分层指标,确定分层指标的权重以及各项指标的标准和权重,采用综合指数评价分级围填海的适宜性为IHI<0.75为Ⅰ级,可以实施围填;IHI=0.75~1.2为Ⅱ级,限制围填,IHI>1.2为Ⅲ级,严禁围填。就珊瑚礁海岸围填海适宜性的分级提出珊瑚礁资源限制性指标以及评估方法的应用。  相似文献   

7.
胡聪  尤再进  毛海英 《海洋科学》2016,40(8):150-156
为了拓展发展空间,围填海已经成为沿海国家海洋开发活动的重大举措,围填海带来巨大的社会和经济效益的同时,对海洋资源会产生许多不利影响,要确定围填海对海洋资源影响程度,急需采用适宜的评价指标体系。分析了受围填海开发活动影响的海洋资源及其影响程度评价指标和权重的确定方法,构建了用于评价围填海开发活动对海洋资源产生影响程度的层次结构指标体系。利用德尔菲法通过三轮专家咨询给出了影响评价指标的权重。研究结果表明:围填海开发活动影响的海洋资源可划分为港航资源、旅游资源、渔业资源、空间资源和其他资源5个方面,在20个评价指标中,浅海滩涂损失率、自然岸线损失比例和珍稀物种资源损失价值的权重较大,陆域空间利用率、人工岸线增加比例、游客增长率、旅游开发投资和海域使用金的权重较小。  相似文献   

8.
围填海活动受到社会经济发展的驱动,其实施会对海洋生态环境产生较大的影响,多种因素之间的相互作用,构成了一类复杂系统。针对象山港海域4个工业与城镇建设区的适宜性评价问题,文章引入岩石工程系统(rock engineering systems,RES)理论的相互作用矩阵计算围填海驱动因素及生态环境影响因子的权重,采用加权模型计算评价对象的适宜性。结果表明,基于RES相互作用矩阵的权重确定方法具有合理性和可行性,适宜性评价结果与实际情况相符,可以为其他区域围填海适宜性评价提供参考。  相似文献   

9.
基于环境经济学和统计学的基础理论和评估方法,确定了船舶工业用海、港口用海、旅游娱乐用海、其它工业用海等重点用海行业,构建了适用于我国海湾的围填海适宜性评价体系,具体包括海岸、动力、冲淤、生物和水质等5个方面适宜性条件指标;在此基础上,测算确定了我国海湾围填海的区位适宜性参数和资源环境适宜性参数;最后,以海州湾北侧为例进...  相似文献   

10.
崔东阳  彭蓉  陈沛歆  唐琳 《海洋科学》2021,45(7):121-126
借鉴《海域定级技术指引(试行)》,本研究构建了深圳市填海类用海的海域定级指标体系,创新性地引入一票否决机制,并将工业、交通运输、渔业基础设施等填海用海和城镇建设填海用海合并,统一为填海类用海进行定级。采用专家打分法确定定级因素和评价因子及其权重,通过聚类分析方法和变异系数(CV)来校核级别,将填海类用海划分为4个级别。该研究为沿海地区开展填海类用海定级提供参考。  相似文献   

11.
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.  相似文献   

12.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

13.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

14.
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.  相似文献   

15.
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone.  相似文献   

16.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics.  相似文献   

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19.
《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   

20.
Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.  相似文献   

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