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1.
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   

2.
围填海工程对莱州湾水动力条件的影响   总被引:1,自引:0,他引:1  
本文采用数值模拟的方法研究了2003—2013年10年来围填海工程建设对莱州湾水动力环境的影响。结果表明2003—2013年围填海工程的建设导致了莱州湾海域面积减小7.38%;围填海工程使莱州湾流速整体呈减小趋势,流速减小超过4cm/s面积约占整个海湾面积的24.3%,流速增加大于4cm/s区域仅占4.0%,流向变化整体较小;莱州湾的纳潮量明显减小,平均纳潮量减小了5.57%;围填海工程建设使莱州湾水交换率略有减小。围填海工程弱化了莱州湾的海湾属性。  相似文献   

3.
环三沙湾区域是海峡西岸经济区重要组成部分,经济发展迅速,围填海活动频繁。为了全面摸清三沙湾围填海状况,以美国Landsat系列卫星影像为数据源,采用人机交互的方式提取了1982—1991年、1991—2001年和2001一2013年间的围填海信息,并进行了时空变化分析。结果表明:研究区30余年来围填海活动频繁,围填海总面积为16 122.99 hm~2,围填海利用类型以水产养殖为主;三个时间段中,1991—2001年间围填海面积最大,为9 950.53 hm~2;空间分布上,三沙湾沿岸围填海主要分布在宁德市,其中福安市围填海面积最大。结合相关资料分析发现,研究区围填海变迁与当地的经济发展历程一致。  相似文献   

4.
人类对海岸带的开发利用活动改造了岸线形态,严重改变海洋区域性流场、水下地形形态及沉积物分布。利用单波束测深、沉积物采样分析等手段,查明研究区海底地形地貌和沉积物分布特征,探讨其沉积物来源。结果显示:①钦州湾水下地形复杂多变,水深为0~20 m,分为中部钦州湾外湾水下地形区、东部三娘湾水下地形区、西部防城港东侧水下地形区及南部湾外水下地形区等4个区域;②地貌分为潮控三角洲、潮流沙脊群、潮流冲刷槽和水下岸坡4个主要海底地貌单元以及潮滩、海蚀平台等潮间带地貌单元;③钦州湾砂质沉积分布广泛,占70%,自茅尾海口门向外海沉积物粒径逐渐变粗,由砂质泥变为泥质砂,再过渡为细砂和中粗砂。沉积物碎屑矿物主要由石英、长石、岩屑、钛铁矿、白钛石和电气石组成,粘土矿物以高岭石为主,其次为伊利石、蒙脱石,沉积物来源为近源河流的陆源输入为主。随着围填海和堤坝建设,钦州湾外湾海岸形态变化巨大,伴随着落潮流速大于涨潮流速的峡道效应,水下地形呈现出槽脊规模和高差加剧,近岸淤积加重的特点。  相似文献   

5.
为研究围填海工程对海湾水动力环境的影响,本文基于二维数值模型MIKE21,建立了东山湾附近海域的潮流模型。对比观测数据发现,大潮期间的最高、最低潮位模拟误差在6 cm以内,小潮期间的误差相对较大;流速和流向的模拟误差在9%左右,最大误差出现在转流时刻;总体来看,模拟结果与观测数据吻合良好。在此模型基础上,研究了东山湾围填海前、后潮流动力、水体半交换时间和纳潮量等水动力要素的变化。结果表明:围填海后大范围的涨落流态与围填海前保持一致,大体上仍然呈现S-N走向,涨潮流偏N向,落潮流偏S向,往复流特征较为明显;从局部流场来看,涨落潮流场发生了一定的变化,围填海区域南、北两侧的流矢变化较为明显,涨潮流矢由偏N向改为偏E向,而落潮流矢由偏S向改为偏W向,同时受到围填海区域岸线的遮蔽效应,围填海南、北两侧水域的流速也有一定减弱,而西侧的流速则有一定增强;围填海实施前的水体半交换时间为220.5 h,实施后时间为239.4 h;纳潮量变化为-2.5%左右。研究表明,围填海工程对东山湾水动力环境的影响主要集中在工程区域附近,其对泥沙冲淤、生态环境等的影响将在后续研究中进一步探讨。  相似文献   

6.
围填海工程的平面设计关系到海洋资源的合理利用,也直接关系到用海项目的生态环境影响,国家海洋局对此提出了指导性意见,而在高含沙量海域,如何应用"意见"提供的3种平面设计方式值得思考。本文结合宁波镇海泥螺山北侧区域建设用海规划,对高含沙量海域围填海项目平面设计问题进行了有益的探讨。分析表明,"意见"倡导的3种平面设计方式并不适合于泥螺山北侧围填海建设,通过结合当地实际情况,提出了3种平面设计方案,从环境、经济和技术等方面综合比较,得出推荐方案。  相似文献   

7.
悬浮物作为污染物示踪剂,对研究海区陆源污染扩散、分布极为重要。利用2008-2017年渤海多个航次的现场实测光谱和悬浮物浓度数据,研究了渤海表层悬浮物浓度遥感反演算法,发现秦皇岛海域悬浮物算法不同于其他渤海区域。将反演算法应用于GOCI静止卫星影像,得到2015年9月13日8个时相的渤海悬浮物浓度空间分布形态,并探讨了8 h短周期内的变异幅度。研究结果表明:渤海大部分悬浮物浓度较低(0~10 mg/L),短周期内变异幅度很小;悬浮物高值主要分布在以黄河三角洲为中心的渤海湾、莱州湾沿岸一带(最高可达300 mg/L),短周期内变异幅度大(60 mg/L以上,可达200 mg/L);辽东湾辽河口区域、复州湾、金州湾附近海域悬浮物浓度相对较高,金州湾部分区域短周期内变异幅度较高,或与该区域围填海等人为活动有关。  相似文献   

8.
本文以莱州湾海洋环境为研究对象,采用数值模拟,分别从海域空间、水动力和生态环境3个方面,分析了2000—2005年、2005—2010年和2010—2013年莱州湾3个阶段围填海工程对其海洋环境产生的累积影响。结果表明,2000—2013年围填海工程导致莱州湾的海域面积减小了约6.3%,岸线长度增加了18.1%;影响流速等级为Ⅲ级的海域面积累积约1 069km~2,大、小纳潮量分别减少了3.81%和4.76%;围填海工程还导致莱州湾的生物资源多样性程度和数量下降。十几年来的围填海对莱州湾海洋环境的累积影响较大。  相似文献   

9.
广东海岸线漫长而曲折,围填海已成为沿海地区缓解工业及城市建设用地紧张的最有效途径。文章在分析广东沿海应因地制宜选择围填海适宜性评价体系的基础上,提出规范区域建设用海规划、改进围填海总体布局与平面设计的必要性,总结在围填海占用滨海湿地、导致近海环境污染和生物多样性减少的背景下,围填海应充分关注公众利益,避免不同利益群体间的矛盾与冲突,并从构建围填海生态补偿评估标准、多渠道筹备围填海生态补偿资金、公众积极参与围填海生态补偿等方面,探讨广东沿海围填海过程中引入和完善生态补偿机制的重要性,为依法、规范开展围填海活动提供相关决策参考,实现广东沿海大开发与海洋生态环境保护和谐、可持续发展。  相似文献   

10.
利用1985—2018年6个时间段的Landsat TM、ETM、OLI遥感影像,使用面向对象的遥感提取方法,通过选取空间利用结构、开发利用程度、景观指数及质心转移分析了沧州市围填海空间格局变化特征。结果表明:33年间研究区内围填海活动剧烈,1985—2018年,沧州近岸海域新增围填海面积137.05 km2,围填用海规模随时间变化不断扩大。1985—2003年,围填海空间利用结构和类型经历了从以围填养殖用海为主到各类型围填用海兼备的演化过程。研究区内围填海强度逐渐上升,2018年围填海开发强度指数达到274.55。港口用海逐渐成为沧州近海海域围填海的主要类型,围海养殖用海次之。1985—2018年,沧州市围填海景观的聚集度指数与蔓延度指数均较高,平均聚集度指数高达99.4004,围填海景观分布具有较强的规律性。沧州市围填海质心不断向东南方向移动,说明沧州市围填海开发的重点区域逐步迁移至沧州南部海域。在当前围填海现状下,应注重后续围填海开发活动的合理规划和集约利用。  相似文献   

11.
填海造陆已经成为全球沿海地区缓解土地短缺、促进社会发展和经济增长的重要手段。随着快速工业化和城市化过程,亚洲已经成为填海造陆的中心。从天津滨海新区到唐山曹妃甸新区,在渤海西北岸正在进行的填海工程其规模在世界上名列前茅。为了剖析海岸带发展的环境因素并促进其可持续发展,对渤海西北岸填海造陆的生态损失采取了回顾性和预测性评价,从生态系统服务角度货币化计算了供给、调节、支持、文化四大类10个方面的生态损失。结果表明:2000-2010年填海造陆的生态损失为9.719亿美元,2010-2020年新增填海造陆的生态损失将达7.021亿美元,其中气体调节和水产品供应方面的损失最大。针对填海造陆可持续发展,提出相关建议,包括:在综合评估基础上的合理规划;减少填海造陆面积;优化填海区土地结构;采用“低影响”开发模式填海;采用生态补偿机制,等。  相似文献   

12.
Gas hydrates are common within near-seafloor sediments immediately surrounding fluid and gas venting sites on the continental slope of the northern Gulf of Mexico. However, the distribution of gas hydrates within sediments away from the vents is poorly documented, yet critical for gas hydrate assessments. Porewater chloride and sulfate concentrations, hydrocarbon gas compositions, and geothermal gradients obtained during a porewater geochemical survey of the northern Gulf of Mexico suggest that the lack of bottom simulating reflectors in gas-rich areas of the gulf may be the consequence of elevated porewater salinity, geothermal gradients, and microbial gas compositions in sediments away from fault conduits.  相似文献   

13.
为详细掌握围填海存量资源状态,提高海域空间资源监管精细化水平,本文提出围填海存量资源概念,并将围填海存量资源划分为围而未填区域、填而未建区域、低密度建设区域、低洼坑塘、低效盐田和低效养殖池塘等6种类型,以及工业区、城镇区等围填海存量资源的消耗类型。在此基础上,采用高空间分辨率卫星遥感影像,建立了面向对象的围填海存量资源遥感影像分类提取方法与技术流程,构建了围填海存量资源指数,并以营口市南部海岸区域为例进行了实证研究。结果表明:(1)面向对象的围填海存量资源遥感影像分类提取方法能够精细地提取围填海存量资源信息,准确率达到90%以上;(2)填而未建区域、低效盐田、低效养殖池塘占研究区围填海存量资源总面积的62.51%,研究区围填海存量资源指数为0.49,但内部差异明显,北部区域为0.66,中部区域为0.44,南部区域为0.37。  相似文献   

14.
Study of the major Asian rivers discharge to the ocean reveals variations of their water discharges and sediment loads.and local characteristics of river sediment concentrations.On the basis of this,the Asian rivers fall into three regions,including Eurasia Arctic,East Asia,Southeast and South Asia Regions.The Eurasia Arctic Region is characterized by the lowest sediment concentration and load,while the East Asia Region is of the highest sediment concentration and higher sediment load,and the South-East and South Asia Region yields Higher Sediment concentration and highest sediment load. The sediment loads of these regions are mainly controlled by climate,geomorphology and tectonic activity.The Eurasia Arctc rivers with large basin areas and water discharge,drain low relief which consists of tundra sediment,thus causing the lowest sediment load.The East Asia rivers with small basin areas and lowest water discharges,drain extensive loess plateau,and transport most erodible loess material,which results in highest sediment concentration.The SE and South Asia rivers originating from the Tibet Plateau have large basin areas and the largest water discharges because of the Summer Monsoon and high rainfall influence,causing the highest sediment load.In Asia,tectonic motion of the Tibet Plateau Plays an important role.Those large rivers originating from the Tibet Plateau trasport about 50% of the world river sediment load to ocean annually,forming large estuaries and deltas,and consequently exerting a great influence on sedimentation in the coastal zone and shelves.  相似文献   

15.
This paper presents a simplified approach to assess the effects of global warming on global coastal groundwater resources over the next century based on the smallest but necessary number of elements such as rainfall, temperature, hydraulic conductivity of the aquifers, and population changes regarding the consumption of groundwater. The positive aspect in this approach is that there is availability of the above elements in the majority of the planet. Methodology includes a sharp interface concept model and simplified estimation of groundwater recharge using limited climate data. The evaluation shows that the future climate changes would decrease fresh groundwater resources in Central American, South American, South African and Australian regions whereas most of the areas in Asia, except South-East Asia. Combinations of fresh groundwater loss and global population are considered to state the vulnerability of future fresh groundwater supply. Vulnerability assessment shows that South Asia, Central America, North Africa and the Sahara, South Africa and the Middle East countries are highly vulnerable whereas, Northern Europe, Western part of South America, New Zealand and Japan are less vulnerable with respect to future fresh groundwater supply. Further, this paper highlights the necessity Integrated Coastal Management (ICM) practices in these vulnerable coastal regions to ensure the sustainable development in coastal regions.  相似文献   

16.
Coastal hypoxia and anoxia have become a serious environmental problem in many coastal ecosystems, and recent evidence suggests an increase in the number of systems experiencing hypoxia globally and an increased frequency and duration of hypoxia in many historically hypoxic systems. Eutrophication, low physical energy and large freshwater input are some of the most important factors, which lead to the development of hypoxia in coastal areas. The Amvrakikos Gulf, located in western Greece, is one of the most important protected areas in Greece and in Europe and past studies indicated that some regions of the Gulf experience hypoxia. Despite the importance of the Amvrakikos Gulf ecosystem, little is known about key ecological, chemical, and physical processes in the Gulf and their relationship with oxygen depletion. In the present study, authors try to answer some important questions regarding the distribution and variation of the hypoxic zone. After a year of measurements, it was concluded that according to spatial distribution of DO, the gulf can be divided into two parts, the western and eastern areas, with important differences occurring between them. Within the western area, the water column was well oxygenated during winter and spring and hypoxic conditions occurred only in summer and autumn. The eastern area was hypoxic throughout the year and anoxic conditions occurred only during autumn. In conclusion, taking into account the author’s measurements and previous studies, the seasonally hypoxic eastern area in 1987 converted into a seasonally anoxic area in 2009 and the western part of the gulf, remained seasonally hypoxic, indicating the degradation of the gulf’s environmental state within the last 20 years.  相似文献   

17.
胶州湾是世界上少有的半封闭天然良港,水深域阔,应以建港为主;目前青岛港年吞吐能力己达8430万t,1997年吞吐量6916万t,集装箱103万TEU,具备建设国际航运中心的各项条件。而在胶州湾建设跨海大桥后将会破坏湾内两个锚地和削弱港口功能,是胶州湾持续利用和青岛可持续发展的障碍。  相似文献   

18.
The evolution of oil pollution in the Gulf of Mexico from April 20 to May 28, 2010, which resulted from the accident on the BP Deepwater Horizon oil platform that occurred on April 20, 2010, is reviewed. The development of the situation was traced on the basis of a joint analysis of optical and radar images (RIs), which proved to be very effective since the optical images made it possible to exclude the areas of calm on the RIs from consideration, and the RIs gave more complete information about dimensions of the areas covered with oil films indiscernible on optical images. It is shown that the mesoscale water dynamics is of prime importance in oil pollution transport in the gulf; therefore, almost all model predictions of a giant oil spill drift were not justified.  相似文献   

19.
The three-parameter generalized-extreme-value (GEV) model has been recommended by FEMA [FEMA (Federal Emergency Management Agency of the United States), 2004. Final Draft Guidelines for Coastal Flood Hazard Analysis and Mapping for the Pacific Coast of the United States. http://www.fema.gov/library/viewRecord.do?id=2188] for frequency analysis of annual maximum water levels in the Pacific coast of the United States. Yet, the GEV model's performance in other coastal areas still needs to be evaluated. The GEV model combines three types of probability distributions into one expression. The probability distributions can be defined by one of the three parameters of the GEV model. In this study, annual maximum water levels at nine water-level stations with long history data (more than 70 years) were chosen for analysis in five coastal areas: Pacific, Northeast Atlantic, East Atlantic, Southeast Atlantic, and Gulf of Mexico coasts. Parameters of the GEV model are estimated by the maximum likelihood estimation (MLE) method. Results indicate that probability distributions are characterized by the GEV Type III model at stations in the Pacific, Northeast, and East Atlantic coastal areas, while they are described by GEV Type II in stations of the Southeast Atlantic and Gulf of Mexico coastal areas. GEV model predictions of extreme water levels show good correlation to observations with correlation coefficients of 0.89 to 0.99. For predictions of 10% annual maximum water levels, the GEV model predictions are very good with errors equal to or less than 5% for all nine stations. Comparison of observations and GEV model estimations of annual maximum water levels for the longest recorded return periods, close to 100 years, revealed errors equal to or less than 5% for stations in the Pacific and Northeast Atlantic coastal areas. However, the errors range from 10% to 28% for other stations located in the East and Southeast Atlantic coasts as well as Gulf of Mexico coastal areas. Findings from this study suggest caution regarding the magnitudes of errors in applying the GEV model to the East and Southeast Atlantic coasts and Gulf of Mexico coast for estimating 100-year annual maximum water levels for coastal flood analysis.  相似文献   

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