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921.
渤海西北岸填海造陆的生态损失及其对海岸带可持续发展的启示 总被引:1,自引:0,他引:1
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
922.
采用2005年采集的SPORT5卫星遥感影像和2015年采集的GF-1卫星遥感影像,分别对2006-2014年之间营口月亮湾海岸空间整治项目实施前后的海岸景观格局进行监测,在此基础上构建了沙滩面积系数、适宜游乐水域指数、主体功能度指数、景观多样性系数、景观变化指数等评估指标,评估了营口月亮湾海岸空间整治效果。结果表明:营口月亮湾沙滩养护工程实施后沙滩面积大幅增加,沙滩面积系数为2.44,适宜游泳嬉水娱乐区面积略有增加,适宜游乐区指数为1.10。海岸空间整理工程实施使月亮湾海岸游乐功能分区明显,月亮湖公园、高尔夫休闲区、山海广场区、农业生态旅游度假区和滨海嬉水观光区主体功能度指数分别达到0.89、0.76、0.68、0.65和0.77。海岸景观美化工程整体改变了海岸景观格局,使各功能分区海岸景观多样性提高,海岸景观格局更为优化,总体景观多样性系数达到1.13,景观变化指数达到0.30。 相似文献
923.
A two-dimensional depth-integrated numerical model is refined in this paper to simulate the hydrodynamics, graded sediment transport process and the fate of faecal bacteria in estuarine and coastal waters. The sediment mixture is divided into several fractions according to the grain size. A bed evolution model is adopted to simulate the processes of the bed elevation change and sediment grain size sorting. The faecal bacteria transport equation includes enhanced source and sink terms to represent bacterial kinetic transformation and disappearance or reappearance due to sediment deposition or re-suspension. A novel partition ratio and dynamic decay rates of faecal bacteria are adopted in the numerical model. The model has been applied to the turbid water environment in the Bristol Channel and Severn estuary, UK. The predictions by the present model are compared with field data and those by non-fractionated model. 相似文献
924.
目前,旅游业已经成为国民经济发展中的重要产业,而旅游业的发展需要外部资金的支持,因此,能否吸引外来资金是一个关系旅游业能否可持续发展的重要问题~([1])。本文尝试构建包含经济环境、旅游业发展、区域条件和外部环境4个层面共32个指标的旅游投资环境评价指标体系,运用因子分析法对我国东部沿海十省市的旅游投资环境进行了综合测评与排序。结果显示,广东省旅游投资环境最好,河北的最差。广东省的各项指标值均高于其他省市,说明其投资吸引力最强。而其他省市各有优劣之处,建议在以后的发展中逐渐改善劣势从而达到改善旅游投资环境。 相似文献
925.
福建省海岸带脆弱生态环境信息图谱研究 总被引:2,自引:0,他引:2
陈菁 《地球信息科学学报》2010,12(2):159-166
海岸带是陆地和海洋的交接地带,随着沿海经济的发展和对外开放,对海岸带的各种开发活动,一方面促进了沿海地区的经济发展,另一方面也使海岸带面临的压力越来越大,如人口增多、资源消耗、环境污染严重等。此外,海岸带的自然灾害频繁,常见的有台风、干旱和地震,海岸带生态环境呈现出典型脆弱性的特征。以地学信息图谱的方法论对海岸带脆弱生态环境进行研究:首先,它依托由对地观测技术、实地调查及社会经济统计而建立起的时空数据库,通过数据挖掘与知识发现,产生征兆图谱;然后,结合评价和时空分析模型及G IS提取诊断图谱;最后,在预测模型的支持下产生实施图谱,从而形成决策方案。实践证明,通过信息图谱能够更直观地反映海岸带脆弱生态环境,包括其现状、驱动因素,以及未来变化趋势,为海岸带的可持续发展规划决策、环境管理,以及防灾减灾对策的制定提供重要的科学依据。 相似文献
926.
The results of an investigation carried out during June 2005 to May 2007 on bloom-forming phytoplankton species composition and abundance in the Parangipettai and Coleroon coastal waters(Southeast coast of India) are reported.Air and surface water temperatures(℃) varied from 25.1 to 30.1 and 24.5 to 28.5,respectively,in the former waters and from 25.5 to 31.2 and 25.0 to 29.3 in the latter waters.The respective salinities varied from 6.0 to 28.5 and 5.0 to 33.1 and the respective pH ranged between 7.0 and 8.3 and 7.2 and 8.3.Correspondingly,the dissolved oxygen content varied from 3.1 to 7.5 and 3.1 to 7.9 mgL-1 while the light extinction coefficient(LEC) values ranged between 3.1 and 10.1 and 1.8 and 11.0.The content ranges of inorganic nutrients,i.e.,nitrate,nitrite,phosphate and silicate(μmolL-1),in the Parangipettai and Coleroon coastal waters were:6.5-27.0;1.0-8.9;0.1-3.0 and 15.0-140 and 10.1-23.4;1.2-8.9;0.2-3.1 and 55-125 respectively.The chlorophyll a contents in both waters ranged from 2.0-7.5 μgL-1.Presently,124 phytoplankton species representing different classes were recorded in the Coleroon coast,viz,Bacillariophyceae(77);Dinophyceae(19);Cyanophyceae(15);Chlorophyceae(10) and Chrysophyceae(3),whereas 117 phytoplankton species were recorded in the Parangipettai coast,viz,Bacillariophyceae(66);Dinophyceae(22);Cyanophyceae(19);Chlorophyceae(7) and Chrysophyceae(3).The phytoplankton cell abundance in the Parangipettai and Coleroon coastal waters varied from 290 to 111662 and 140 to 132 757 cells L-1,respectively,with peak diversity(3.38 and 3.52 bits ind-1.) recorded in summer.The maximum abundance occurred in summer coinciding with the stable hydrographical conditions.The seasonal distribution and abundance of phytoplankton are discussed in relation to hydrographical parameters.Totally 31 and 24 species of phytoplankton were found to be bloom-forming in the Parangipettai and Coleroon coastal waters,respectively.Presently Trichodesmium bloom was also observed,which appeared at the 10 fathom level of the coastal water and quickly spread to the marine zone of the Vellar estuary and near the mouth region of the mangrove waters.The Parangipettai and Coleroon coastal waters are subject to long term fluctuations in physico-chemical conditions depending upon the seasonal tidal range and freshwater influx,resulting in a continuous exchange of organic,inorganic,plant and animal matters. 相似文献
927.
928.
A multi-residual method based on stir bar sorptive extraction coupled with thermal desorption-gas chromatography-mass spectrometry (SBSE-TD-GC-MS) has been developed to measure 49 organic pollutants (organochlorine pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polybrominated diphenyl ethers and nonylphenol) in seawater. Using 100 ml of water, the method exhibited good linearity, with recoveries between 86% and 118% and relative standard deviation between 2% and 24% for almost all compounds. The method was applied to determine target contaminants in Catalonian seawater, including coastal areas, ports and desalination plant feed water. Overall individual compound levels oscillated between 0.16 and 597 ng l−1; PAHs and nonylpenol were the compounds found at the highest concentrations. The method provided LODs between 0.011 and 2.5 ng l−1, lower than the Environmental Quality Standards (EQS) fixed by Directive 2008/105/EC. In compliance with the directive, this method can be used as a tool to survey target compounds and is aimed at protecting coastal ecosystems from chemical pollution. 相似文献
929.
930.
Katsuto Uehara Pramot Sojisuporn Yoshiki Saito Thanawat Jarupongsakul 《地球表面变化过程与地形》2010,35(14):1701-1711
Seasonal variation in seabed elevation in the muddy intertidal zone of the Chao Phraya River delta, an area of serious coastal erosion for 40 years, was assessed using information on waves and tides predicted by numerical simulations. The study area is under the influence of the Southeast Asian monsoon climate and lies in the innermost part of a sheltered gulf, across which a low‐gradient slope has developed. Observations, aimed at evaluating the effectiveness of a prototype breakwater on mitigating coastal erosion, indicated that the seasonal variation in the seabed elevation, typically about 30 cm, was caused primarily by seasonal changes in wave direction and height. The breakwater seems to have contributed to a net rise in the seabed level at sites behind the structure. Seabed erosion was most apparent during the northeast monsoon, when waves are weak. Erosion under this low wave energy state was attributed to the combined effect of wave breaking and the low tidal level. A difference in the observed seabed accretion rate between the transitional intermonsoon period and the succeeding southwest monsoon period was attributed to the direction of the wave energy flux; offshore sediments seem to have been supplied efficiently to the study area by waves during the transitional period. Another potential cause of seabed erosion and accretion during the wet southwest monsoon season was the discharge of water and sediments from local canals associated with intense tropical rainfall; this discharge seems to be linked to land use in the coastal area. The results of this study show the importance of monitoring across‐shore sediment transport for better understanding of coastal erosion processes. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献