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1.
Like many delta systems, the coastal zoneof the Nile delta has been designated as avulnerable zone to a rising sea level as aconsequence of expected climate changescombined with geological and human factors.In view of the understanding of thesefactors, a degree of vulnerabilityanalysis has been carried out to betterlocate which sectors need to be assessedand adapted to possible sea level rise(SLR) for the Nile delta-Alexandria region of Egypt.Results reveal that not all of the coastalzones of the Nile delta are vulnerable toaccelerated sea-level rise at the samelevel. Based on multiple criteria the Niledelta-Alexandria coast can be categorizedinto vulnerable (30%), invulnerable (55%)and artificially protected coastalstretches (15%). These criteria include:local subsidence or uplifting, relativesea-level rise (RSLR), land topography,width of lagoon barriers, beach-face slope,high-elevated features such as dunes andridges, eroding and accreting coastlinesand protection works.Moreover, this study evaluates thelong-term relative sea-level rise andsubsidence rates along the Nile delta andAlexandria coasts. Statistical analysis oflong-term tide gauge data recorded atAlexandria, Burullus and Port Said yieldsvalues of 1.6, 1.0 and 2.2 mm/yr,respectively. These values of relativesea-level rise and long-term subsidencerate obtained from age-dated sediment coresections are inconsistent: long-termsubsidence appears to be larger (maximum of7 mm/ yr). This discrepancy might beexplained if the subsidence is episodic,and occurs rather abruptly during majorearthquakes that occur every few hundredyears associated with fault trend lines.Rising sea levels could have significantlongterm impacts on the Nile delta,including the distribution of ground watersalinity and erosion of the narrow andlow-lying barriers of the Burullus andManzala lagoons. Adaptive measures alongthe study area particularly those relatedto coastal protective structures are alsoevaluated.  相似文献   

2.
杨曦  王中良 《地球与环境》2014,42(2):157-161
相对海平面上升是一个缓慢、渐进过程,但长期的积累可以使得上升幅度相当可观,从而加剧风暴潮、海岸侵蚀、海水入侵和咸潮等灾害致灾程度。基于验潮位监测和卫星观测结果显示,全球海平面在20世纪中期平均上升1.5~2.0 mm/a,而近30年中国沿海海平面上升速率为2.6~2.7 mm/a,高于全球平均值。渤海湾天津地区由于地面沉降显著,而导致相对海平面大幅度上升。滨海地区地面沉降速率在未来50至100年内可能会稳定在1.0~2.0 cm/a范围,结合目前海平面上升速率2.7 mm/a,总的相对海平面上升速率处于12.7~22.7 mm/a范围。由此估计,到2050年,天津地区相对海平面将比2012年高出48.3~86.3 cm,而到2100年,将比2012年高出111.8~199.8 cm。  相似文献   

3.
海南岛四周以自然岸线为主,其中砂质岸线占岸线总长度的43.1%,极易遭受侵蚀,海岸侵蚀造成的海岸坍塌、岸线后退造成的大片土地资源及滩涂流失、海防林损毁等在海南岛四周沿岸均有发生。本文通过现场调查和多年监测资料,选出七处典型侵蚀岸段,对各岸段海岸侵蚀的特点进行分析,认为海南岛不同岸段的侵蚀主导因素各不相同,主要为河口冲刷侵蚀型、热带气旋浪潮影响侵蚀型、人工构筑物影响侵蚀型和自然水动力与地形配合侵蚀型四种类型,同时根据监测资料对各岸段海岸侵蚀强度进行评价。  相似文献   

4.
Coastal flooding affects physical and social place attachments. Values-based approaches to climate change adaptation examine how risks to place attachments are distributed within and among communities, with a view to informing equitable adaptation policies. In this nascent body of research, divergent theoretical frameworks and empirical approaches to measuring social values are evolving. While some studies explore the things people value about their everyday lives generally—the lived values approach, others locate specific social and cultural values in geographic space—the landscape values mapping approach. This study aims to compare the explanatory value of these two approaches for understanding the social risks of sea-level rise, and appraise whether either or both approaches are likely to meet local adaptation planning needs. It does this by examining the potential social impacts of sea-level rise in Kingston Beach, Australia, informed by a mail-out survey of the community. The lived values approach identified that the natural environment, scenery, relaxed lifestyle and safety are highly important to local residents, while the landscape values mapping approach revealed that Kingston Main Beach is the most highly valued of eight coastal landscape units. Incorporating the landscape values mapping into the lived values cluster analysis revealed that while Kingston Main Beach is highly important for its recreational value to some members of the community, for others manmade features such as community halls or sports ovals may be of higher importance because they facilitate social interactions. There is potential to further integrate these two approaches to better inform adaptation policy about how lived and landscape values are distributed among communities, where they are located in space and whether they change over time. A deeper understanding of such assigned values can lead to improved engagement with coastal residents to inform adaptation policy now and into the future.  相似文献   

5.
Globally, sea level has been rising for more than the last one hundred years, and is expected to do so into the foreseeable future, and at an accelerating rate. The direct influences of sea-level rise on water resources come principally from the following: new or accelerated coastal erosion; more extensive coastal inundation and higher levels of sea flooding; increases in the landward reach of sea waves and storm surges; seawater intrusion into surface waters and coastal aquifers; and further encroachment of tidal waters into estuaries and coastal river systems. The impacts of sea-level rise are likely to be felt disproportionately in certain areas, reflecting both natural and socio-economic factors that enhance the levels of risks. The opportunity to learn about the likely nature of, and most appropriate adaptation to, the anticipated impacts of sea-level rise on water resources is arguably best developed in rapidly subsiding coastal areas, and especially in low-lying deltas where subsidence rates are typically much larger than the historic rise in global mean sea level. Significantly, such areas are often major centres of population and of economic activity, thereby highlighting the human dimensions of sea-level rise. Sound management of the risks to water resources associated with sea-level rise requires enhancing adaptive capacity, mainstreaming adaptation, harmonizing responses to extreme events, variability and long-term change and strengthening regional and international cooperation and coordination. In this regard, the policies and initiatives of international organisations are not always entirely consistent with the needs of developing countries.  相似文献   

6.
以Landsat ETM/ TM影像为主要数据源,采用人机交互的方式提取了1990~2017年间6期乐清湾海岸线。利用马尔科夫矩阵法计算了滩涂转化规律,并按照年份进行岸线和海岸湿地变迁分析。结合当地相关资料,开展了乐清湾区域海岸线和海岸湿地变化的驱动力分析。结果表明:乐清湾岸线以人工岸线为主,岸线变化剧烈,变化速率分布不均,海岸湿地的变化整体面积变化不大,其中人工湿地主要由自然滩涂湿地转化而来,人类围填是乐清湾海岸线和海岸湿地变迁的主要因素。  相似文献   

7.
Coastal regions worldwide are during the process of rapid urban expansion. However, expanded urban settlements in land-sea interfaces have been faced with unprecedented threats from climate change related hazards. Adaptation to coastal hazards has received increasing attention from city managers and planners. Adaptation and land management practices are largely informed by remote sensing and land change modeling. This paper establishes a framework that integrates land change analysis, coastal flooding, and sea level rise adaptation. Multilayer perceptron neural network, similarity learning, and binary logistic regression were applied to analyze spatiotemporal changes of residential, commercial, and other built-up areas in Bay County, Florida, USA. The prediction maps of 2030 were produced by three models under four policy scenarios that included the population relocation strategy. Validation results reveal that three models return overall acceptable accuracies but generate distinct landscape patterns. Predictions indicate that planned retreat of residents can greatly reduce urban vulnerability to sea level rise induced flooding. While managed realignment of the coast brings large benefits, the paper recommends different mixes of adaptation strategies for different parts of the globe, and advocates the application of reflective land use planning to foster a more disaster resilient coastal community.  相似文献   

8.
渤海湾岸线变化(2003—2011年)对近岸海域水质的影响   总被引:6,自引:1,他引:5  
为研究渤海湾岸线对近岸海域水质的影响,本研究首先阐述了2003、2010和2011年的渤海湾海岸线变迁情况,采用数值模拟的方法研究了由岸线变迁引起的渤海湾水动力条件的变化情况,之后应用综合污染指数法筛选出渤海湾近岸海域的2003、2010、2011年的主要污染指标,并探讨了因岸线变化引起的渤海湾近岸海域主要污染指标污染范围的变化情况.结果表明,与2003年相比,2010年渤海湾的各个港口都有了很大程度的扩张,部分滩涂地区变成陆地;渤海湾余流场的主要变化是天津港北部存在的逆时针余流消失,天津港南部至黄骅港北部间的逆时针沿岸余流有所减小;渤海湾2003、2010和2011的水质的主要污染指标为营养盐类、重金属类的Zn和Pb;渤海湾近岸海域主要污染指标的污染范围有所扩大,污染物高值区有向渤海湾东北海域扩展的趋势.  相似文献   

9.
Carbon dioxide (CO2) emissions from aquatic ecosystems are important components of the global carbon cycle, yet the CO2 emissions from coastal reservoirs, especially in developing countries where urbanization and rapid land use change occur, are still poorly understood. In this study, the spatiotemporal variations in CO2 concentrations and fluxes were investigated in Wenwusha Reservoir located in the southeast coast of China. Overall, the mean CO2 concentration and flux across the whole reservoir were 41.85 ± 2.03 µmol/L and 2.87 ± 0.29 mmol/m2/h, respectively, and the reservoir was a consistent net CO2 source over the entire year. The land use types and urbanization levels in the reservoir catchment significantly affected the input of exogenous carbon to water. The mean CO2 flux was much higher from waters adjacent to the urban land (5.05 ± 0.87 mmol/m2/hr) than other land use types. Sites with larger input of exogenous substance via sewage discharge and upstream runoff were often the hotspots of CO2 emission in the reservoir. Our results suggested that urbanization process, agricultural activities, and large input of exogenous carbon could result in large spatial heterogeneity of CO2 emissions and alter the CO2 biogeochemical cycling in coastal reservoirs. Further studies should characterize the diurnal variations, microbial mechanisms, and impact of meteorological conditions on reservoir CO2 emissions to expand our understanding of the carbon cycle in aquatic ecosystems.  相似文献   

10.
Climate change may affect the frequency, intensity, and geographic distribution of severe coastal storms. Concurrent sea-level rise would raise the baseline of flooding during such events. Meanwhile, social vulnerability factors such as poverty and disability hinder the ability to cope with storms and storm damage. While physical changes are likely to remain scientifically uncertain into the foreseeable future, the ability to mitigate potential impacts from coastal flooding may be fostered by better understanding the interplay of social and physical factors that produce human vulnerability. This study does so by integrating the classic causal model of hazards with social, environmental, and spatial dynamics that lead to the differential ability of people to cope with hazards. It uses Census data, factor analysis, data envelopment analysis, and floodplain maps to understand the compound social and physical vulnerability of coastal residents in the city of Revere, MA, USA. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

11.
Managing risk by adapting long-lived infrastructure to the effects of climate change must become a regular part of planning for water supply, sewer, wastewater treatment, and other urban infrastructure during this century. The New York City Department of Environmental Protection (NYCDEP), the agency responsible for managing New York City’s (NYC) water supply, sewer, and wastewater treatment systems, has developed a climate risk management framework through its Climate Change Task Force, a government-university collaborative effort. Its purpose is to ensure that NYCDEP’s strategic and capital planning take into account the potential risks of climate change—sea-level rise, higher temperature, increases in extreme events, changes in drought and flood frequency and intensity, and changing precipitation patterns—on NYC’s water systems. This approach will enable NYCDEP and other agencies to incorporate adaptations to the risks of climate change into their management, investment, and policy decisions over the long term as a regular part of their planning activities. The framework includes a 9-step Adaptation Assessment procedure. Potential climate change adaptations are divided into management, infrastructure, and policy categories, and are assessed by their relevance in terms of climate change time-frame (immediate, medium, and long term), the capital cycle, costs, and other risks. The approach focuses on the water supply, sewer, and wastewater treatment systems of NYC, but has wide application for other urban areas, especially those in coastal locations.  相似文献   

12.
厦门海岸线遥感动态监测研究   总被引:2,自引:0,他引:2  
以厦门地区海岸影像为研究对象,根据不同海岸类型的地貌特点,采用不同的海岸线遥感解译方法提取出1987年、1997年和2007年的海岸线,并进行岸线变迁原因分析,研究结果表明:人工海岸、基岩海岸、砂质海岸及红土海岸的海岸线解译标志明显,提取效果较好,基本能够实现计算机自动提取;淤泥质海岸在遥感图像上呈现复杂的边缘,无理想的线性特征自动提取技术,是海岸线提取中的难点.  相似文献   

13.
为了预防和减轻未来海平面上升所造成的淹没对山东沿渤海湾地区的影响,本文采用IPCC全球平均海平面上升数据、沿渤海湾地区地壳垂直运动数据、东风港潮位数据预测2100年100 a一遇的潮位线数据,并借助数字高程模型(DEM)、地理信息系统(GIS)预测海平面上升对潮位线位置的影响。研究结果为:(1)表达2100年潮位线位置的数据;(2)与2000年相比,2100年100 a一遇风暴潮增加的淹没区的空间分布图;(3)与2000年相比,2100年100 a一遇风暴潮增加的淹没区面积和向陆推进距离。预测结果表明:(1)2100年淹没范围随海平面上升幅度增加而增加;(2)相对于2000年,2100年新增的淹没区主要分布于研究区的中西部地区;(3)新增淹没地区人口、工业、农、林、牧、渔业将受到严重影响。  相似文献   

14.
As pressures on coastal zones mount, there is a growing need for frameworks that can be used to conceptualize complex sustainability challenges and help organize research that increases understand about interacting ecological and societal processes, predicts change, and supports the management, persistence, and resilience of coastal systems. The Driver–Pressure–State–Impact–Response (DPSIR) framework is one such approach that has been adopted in some coastal zones around the world. Although the application of the DPSIR framework has considerable potential to bridge the gap between scientific disciplines and link science to coastal policy and management, current applications of DPSIR in coastal environments have been limited and new innovations in the application of the DPSIR model are needed. We conducted a structured review of literature on the DPSIR framework as applied to the function, process and components of complex coastal systems. Our specific focus was on how the DPSIR framework has been used as a tool to organize sophisticated empirical scientific research, support transdisciplinary knowledge at a level appropriate for building understanding about coastal systems, and how adopting a DPSIR approach can help stakeholders to articulate and structure challenges in coastal systems and use the framework to support policy and management outcomes. The review revealed that DPSIR models of coastal systems have been largely used to support and develop conceptual understanding of coastal social–ecological systems and to identify drivers and pressures in the coastal realm. A limited number of studies have used DPSIR as a starting point for semi-quantitative or quantitative analyses, although our review highlights the continued need for, and potential of, transformative quantitative analyses and transdisciplinary applications of the DPSIR framework. The DPSIR models we reviewed were predominantly single sector, encompassing ecological or biophysical factors or focusing primarily on socio-cultural dimensions rather than full integration of both types of information. Only in eight of 24 shortlisted articles did researchers actively engage decision-makers or citizens in their research: given the potential opportunity for using DPSIR as a tool to successfully engage policy-makers and stakeholders, it appears that the DPSIR framework has been under-utilized in this regard.  相似文献   

15.
Sea-level rise due to climate change creates new risks of submersion in coastal areas that must be taken into account. Although these are long-term risks for 2100, it is important to anticipate possible consequences in order to identify the most vulnerable areas or issues and develop the appropriate adaptation policies. The aim of this paper is to examine the consequences of such sea-level rise for wetlands in the Languedoc-Roussillon region (France) which is particularly at risk of submersion. The analysis is based on the worst case scenario of a one meter sea level rise by 2100, with a variety of adaptive strategies: denial, laissez-faire and strategic retreat of infrastructure and buildings. This latter strategy assumes that the retreat wetlands is unconstrained. The evaluation examines the losses and transformations of ecological habitats, depending on their distance from salt water. Estimating damages and benefits requires first, to study the evolution of the services supplied by different habitats and second, to estimate the value of the economic impact. This approach demonstrates the superiority of a strategic retreat policy which would halve the damages resulting from submersion.  相似文献   

16.
海岸线对海平面上升、海岸侵蚀、港湾淤积、湿地生态资源和近海海域环境等具有重要指示作用。利用遥感(remote sensing, RS)和地理信息系统(geographic information system, GIS)技术获取苏北海岸在1978年至2018年5期海岸线数据,对海岸线长度变化、岸线速率变化以及岸线类型转变进行分析,并以河口为分界点对岸线变迁特征分段分析。结果表明:(1)40 年间研究区岸线总长度大致呈现递减趋势,岸线类型变化较为明显,随时间推移人工岸线和自然岸线分别表现为增长和削弱的趋势。(2)研究区在1978年至2018年,海岸线向海域推进速率远大于海岸线向陆域推进速率。(3)1978年至1988年,射阳河口至新阳港口之间的海岸线推进速率最为明显,主要以自然淤长的方式向海域推进,岸线平均端点速率(end point rate, EPR)为281.4 m/a;在1988至1998年,新阳港口到斗龙港口之间岸线推进速率最为明显,主要以自然淤长方式向海域推进,平均EPR为535.5 m/a;在1998年至2008年,斗龙港口到大丰港口之间岸线推进速率最为明显,主要以人工围垦方式向海域推进,平均EPR为502.1 m/a;在2008年至2018年,梁垛河口到方塘河口之间岸线推进速率最为明显,主要以人工围垦方式向海域推进,平均EPR为347.7 m/a。  相似文献   

17.
Climate change impacts on the hydrological cycle, e.g. leading to changes of precipitation patterns, have been observed over several decades. Higher water temperatures and changes in extremes hydrometeorological events (including floods and droughts) are likely to exacerbate different types of pressures on water resources with possible negative impacts on ecosystems and human health. In addition, sea-level rise is expected to extend areas of salinisation of groundwater and estuaries, resulting in a decrease of freshwater availability for humans and ecosystems in coastal areas. Furthermore, climate-related changes in water quantity and quality are expected to affect food availability, water access and utilisation, especially in arid and semi-arid areas, as well as the operation of water infrastructure (e.g. hydropower, flood defences, and irrigation systems). This paper serves as an introduction to the special issue of Environment Science & Policy dealing with climate change impacts on water-related disasters. It provides a brief background about relevant EU water policies and examples of EU-funded research trends which illustrate on-going efforts to improve understanding and modelling of climate changes related to the hydrological cycles at scales that are relevant to decision making (possibly linked to policy).  相似文献   

18.
基于数学模型的海平面上升对咸潮上溯的影响   总被引:3,自引:2,他引:1  
气候变化导致的海平面上升对沿海地区构成极大的威胁,海平面上升已经成为全球重要的环境问题,受到社会各界的高度重视。研究建立了一维动态潮流-含氯度数学模型,计算了海平面上升对咸潮上溯的影响,结果显示:250 mg/L的咸度线随着上游来水频率的增大,咸潮上溯距离明显增大;一定上游来水条件下,随着海平面的上升,咸潮上溯界线向上游方向移动显著。并详细计算了代表口门在海平面上升10 cm、30 cm和60 cm的情况下,咸潮界线的具体上移距离,以期给三角洲地区城市供水、农业灌溉引水等提供理论指导,减轻海平面上升危害,以确保21世纪中国沿海地区资源、环境、经济和社会的可持续发展。  相似文献   

19.
科尔沁沙地及其周围地区土地利用变化的情景分析   总被引:19,自引:0,他引:19  
根据科尔沁沙地及其周围地区过去15年(1985~2000年)土地利用的时空动态变化、2000年的土地利用格局以及2010年的土地利用规划数据,构建了模拟研究地区土地利用变化的CLUE-S模型。在该模型的支持下,论文分别对研究地区未来10年(2000~2010年)土地利用变化格局的马尔柯夫情景和规划情景进行了模拟,然后,通过2000年土地利用现状图与2010年情景模拟图的叠加,分析了在以上两种情景下土地利用变化的共同之处及差异。研究结果对完善科尔沁沙地及其周围地区土地利用变化的动态管理具有重要意义。  相似文献   

20.
This paper reports sea level rise (SLR) scenarios causing land loss, environmental degradation and destruction of infrastructure in the Saudi coast of the Arabian Gulf. Human development structures such as, sea ports, desalination plants, industrial establishments, commercial buildings, fish farms etc. will be impacted, leading to great economic losses. A systematic analysis on the current environmental setting of east coast of Kingdom of Saudi Arabia (KSA) versus the existing infrastructure assets indicates that a 1?m sea level rise in Arabian Gulf affects approximately 650?km2 land area, along the Saudi coastline of ~1,800?km in 1:50,000 scale. Three simulation scenarios were created with respect to 1?m, 2?m and 3?m rises from the present mean sea level and its impacts were assessed. Maps depicting major infrastructure assets, ecologically sensitive elements, historical locations, anthropogenic zones, and Environmental Sensitivity Indices (ESI) were used for overlaying the sea level change map, in a Geographic Information System (GIS) platform. In general, the Jubail Marine Park area will have serious impact due to SLR. The inundation of low?Clying lands will affect the mangroves species of Dawhat Ad Dafi, coral reefs, coastal salt marshes, groundwater aquifers, and fish stocks. The risk of inundation on the Abu Ali Island, given their status as marine sanctuary of international importance, is particularly high. As an adaptation strategy, it is proposed that the KSA should implement Integrated Coastal Zone Management Plan (ICZMP) for the Arabian Gulf coast without further delay for the protection of its vulnerable resources and for sustainable development.  相似文献   

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