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1.
Marine ecosystem services are the benefits which people obtain from the marine ecosystem, including provisioning ser-vices, regulating services, cultural services and supporting services. The human species, while buffered against environmental changes by culture and technology, is fundamentally dependent on the flow of ecosystem services. Marine ecosystem services be-come increasingly valuable as the terrestrial resources become scarce. The value of marine ecosystem services is the monetary flow of ecosystem services on specific temporal and spatial scales, which often changes due to the variation of the goods prices, yields and the status of marine exploitation. Sensitivity analysis is to study the relationship between the value of marine ecosystem services and the main factors which affect it. Uncertainty analysis based on varying prices, yields and status of marine exploitation was carried out. Through uncertainty analysis, a more credible value range instead of a fixed value of marine ecosystem services was obtained in this study. Moreover, sensitivity analysis of the marine ecosystem services value revealed the relative importance of different factors.  相似文献   

2.
 海面溢油对生态环境造成了严重危害,故及早发现和尽快处理对降低事故影响和经济损失起着至关重要的作用。合成孔径雷达(SAR)是观测海面溢油、快速检测和事故态势分析判断的有效技术途径。本文针对SAR图像的海面溢油检测,提出了一种特征概率函数的双阈值分割方法。首先,通过高低阈值分割提取不同层次的灰度信息,再利用密度估计提取灰度的空间分布信息,然后,通过构建概率函数对油膜和类油膜区域进行形态学分类,最后,结合辅助信息,获得最终的海面溢油检测结果。本文利用香港中文大学卫星地面站接收的ENVISAT ASAR图像开展实验,结果表明,本文提出的方法能够准确地排除由风场或者水流场导致的低散射区域,有效地检测和识别生成不久的中型油膜,从而有助于溢油事故的早期预警与处置。  相似文献   

3.
Marine oil spills are among the most signifi cant sources of marine pollution. Synthetic aperture radar(SAR) has been used to improve oil spill observations because of its advantages in oil spill detection and identifi cation. However, speckle noise, weak boundaries, and intensity inhomogeneity often exist in the oil spill regions of SAR imagery, which will seriously aff ect the accurate identifi cation of oil spills. To enhance marine oil spill segmentation of SAR images, a fast, edge-preserving framework based on the distance-regularized level set evolution(DRLSE) model was proposed. Specifi cally, a bilateral fi lter penalty term is designed and incorporated into the DRLSE energy function(BF-DRLSE) to preserve the edges of oil spills, and an adaptive initial box boundary was selected for the DRLSE model to reduce the operation time complexity. Two sets of RadarSat-2 SAR data were used to test the proposed method. The experimental results indicate that the bilateral filtering scheme incorporated into the energy function during level set evolution improved the stability of level set evolution. Compared with other methods, the proposed improved BF-DRLSE algorithm displayed a higher overall segmentation accuracy(97.83%). In addition, using an appropriate initial box boundary for the DRLSE method accelerated the global search process, improved the accuracy of oil spill segmentation, and reduced computational time. Therefore, the results suggest that the proposed framework is eff ective and applicable for marine oil spill segmentation.  相似文献   

4.
Marine risers play a key role in the deep and ultra-deep water oil and gas production. The vortex-induced vibration (VIV) of marine risers constitutes an important problem in deep water oil exploration and production. VIV will result in high rates of structural failure of marine riser due to fatigue damage accumulation and diminishes the riser fatigue life. In-service monitoring or full scale testing is essential to improve our understanding of VIV response and enhance our ability to predict fatigue damage. One marine riser fatigue acoustic telemetry scheme is proposed and an engineering prototype machine has been developed to monitor deep and ultra-deep water risers’ fatigue and failure that can diminish the riser fatigue life and lead to economic losses and eco-catastrophe. Many breakthroughs and innovation have been achieved in the process of developing an engineering prototype machine. Sea trials were done on the 6th generation deep-water drilling platform HYSY-981 in the South China Sea. The inclination monitoring results show that the marine riser fatigue acoustic telemetry scheme is feasible and reliable and the engineering prototype machine meets the design criterion and can match the requirements of deep and ultra-deep water riser fatigue monitoring. The rich experience and field data gained in the sea trial which provide much technical support for optimization in the engineering prototype machine in the future.  相似文献   

5.
The dynamic microcosms were used to evaluate the effect of oil spills on microbial ecological system in marine sediment and the enhancement of nutrient on the oil removal. The function and structure of microbial community caused by the oil pollution and phosphate dosage were simultaneously monitored by dehydrogenase activity assay and PCR-denaturing gradient gel electrophoresis (DGGE) techniques. The results indicated that the amount of total bacteria in all dynamic microcosms declined rapidly with incubation time. The number of petroleum-degrading bacteria and the activity of sediment dehydrogenase were gradually enhanced by petroleum in the oil-treated microcosms, while they both showed no obvious response to phosphate dosage. In comparison, phosphate spiked heterotrophic bacteria and they showed a significant increase in amount. DGGE profiles indicated that petroleum dosage greatly changed community structure, and the bacteria belonged to class Deltaproteobacteria, and phyla Bacteroidetes and Chlorobi were enriched. This study demonstrated that petroleum input greatly impacted the microbial community structure and consequently the marine sediment petroleum-degrading activity was enhanced. Phosphate dosage would multiply heterotrophic bacteria but not significantly enhance the petroleum degradation.  相似文献   

6.
国际海洋新秩序及其对我国海洋经济的影响   总被引:1,自引:0,他引:1  
国际海洋新秩序的形成以<联合国海洋法公约>的生效为标志.<公约>不仅赋予了沿海国对200 n mile专属经济区的主权权利等海洋权益,带来国际海洋形势的新趋势,而且会对我国海洋经济产生重要影响.<公约>的生效一方面促进了我国海洋法律的建设进程,扩大了海洋管辖;另一方面又使我国海洋经济权益受到新的威胁.专属经济区制度对我国海洋渔业生产和管理也将产生重要影响.  相似文献   

7.
China is a country with a vast marine territory whose area covers one third of the total land territory area. With the exploitation of marine resources and the development of marine economy, marine economic regions have been formed gradually. We shouldn’t ignore them when we divide economic regions throughout the whole nation, especially in our country. In this paper, we’ Il expand division principles, practice and methods of marine comprehensive economic region. Liaoning Province, facing the Yellow Sea and the Bohai sea, is not only a part of Round-the-Bohai Sea Economic Region, but a part of national marine econemic region. Through evaluating marine resources of Liaoning, and analyzing development of marine economy, composition of marine industries and distributional characteristic of marine economy, Liaoning marine region is divided into Bohai Sea marine economic region and Yellow Sea marine economic region based on differences of marine economy. Thereby we go further into the formation of regional marine economic region and distributional mechanism of regional marine economy. Foundation item: Subsidized by the National Natural Science Foundation of China(49671022). Biography: ZHANG Yao-guang(1934–), male, a native of Shanghai City, professor. His research interest includes marine economic geography.  相似文献   

8.
China is a large marine country. Developing marine economy is an effective way to solve a series of problems with which man is faced, such as the want of natural resources, space limitation, the environmental deterioration, etc. This article analyzes the rich resources of marine biology, harbor, offshore oil and natural gas and coastal tourism resources in China and describes the developing features and regional differences of marine economy. To realize the sustainable development of marine economy in China, what we need to do are as follows: 1 ) to list exploiting ocean into national development strategy; 2) to realize integrated economy of sea and land; 3) to develop ocean by science and technology; 4) to perfect legal institution of marine environment; 5) to establish new idea of sea defending.  相似文献   

9.
Based on dynamic response signals a damage detection algorithm is developed for marine risers. Damage detection methods based on numerous modal properties have encountered issues in the researches in offshore oil community. For example, significant increase in structure mass due to marine plant/animal growth and changes in modal properties by equipment noise are not the result of damage for riser structures. In an attempt to eliminate the need to determine modal parameters, a data-based method is developed. The implementation of the method requires that vibration data are first standardized to remove the influence of different loading conditions and the autoregressive moving average (ARMA) model is used to fit vibration response signals. In addition, a damage feature factor is introduced based on the autoregressive (AR) parameters. After that, the Euclidean distance between ARMA models is subtracted as a damage indicator for damage detection and localization and a top tensioned riser simulation model with different damage scenarios is analyzed using the proposed method with dynamic acceleration responses of a marine riser as sensor data. Finally, the influence of measured noise is analyzed. According to the damage localization results, the proposed method provides accurate damage locations of risers and is robust to overcome noise effect.  相似文献   

10.
西北农牧交错带生态环境脆弱,区位特殊性和生态重要性使其在我国社会经济发展和生态环境保护方面具有重要战略意义。通过对该区域进行土地利用优化配置,使有限的土地资源支撑起生态环境保护和经济发展的重任是本文的出发点。多目标遗传算法和FLUS模型的应用可以从多方面(数量结构、空间布局、综合效益)完善土地利用优化配置,为土地利用优化配置提供更多的选择方案。本文选用多目标遗传算法和FLUS模型对该区域进行2025年的土地利用变化模拟,通过设置自然发展、生态保护优先、经济发展优先、生态-经济均衡4种情景,探讨了如何在兼顾生态环境保护与社会经济发展的情况下进行土地利用的优化配置。结果表明,基于生态-经济均衡情景下的优化方案,土地利用类型的数量结构和空间布局更为合理,其综合效益优于另外3种情景。该情景在合理限制经济发展速度的前提下,使生态建设获得稳定发展,其经济效益较生态保护优先情景下增长了8.96%,生态效益较经济发展优先情景下增长了0.77%,在生态保护与经济发展2种目标之间达到平衡,为西北农牧交错带的土地利用规划提供了决策辅助。  相似文献   

11.
多元指标的海上溢油信息提取   总被引:1,自引:0,他引:1  
 海上溢油给海洋生态环境带来了巨大的影响,甚至需要几十年才能恢复。运用卫星遥感进行海上溢油监测已成为目前溢油监测的主要手段。本文对海上溢油遥感监测方法进行了分析,鉴此,提出了一种SAR数据的多元指标溢油信息提取方法。首先,对图像进行分割,然后,建立溢油形状参数、纹理特征指数、物理特性指数等主要指标,并以层次分析法得出每一类指标的权重。针对每一类指标,以经现场验证的溢油图像为基础,选择形状参数,如周长与面积比值、复杂度等,建立溢油形状判读等级;选择纹理特征参数,以灰度共生矩阵的相关性、熵、变化等来表达溢油的纹理特性,建立溢油纹理特征判断等级;选择溢油物理特征,如溢油与海水的标准差、均方根差、对比度等,建立溢油物理参数判断等级。在此基础上,建立海上溢油遥感信息提取指数,计算分割图斑的溢油遥感信息提取指数,以此判断溢油遥感信息提取的置信度,为溢油识别提供依据。  相似文献   

12.
In order to archive,quality control and disseminate a large variety of marine data in a marine data exchange platform,a marine XML has been developed to encapsulate marine data,which provides an efficient means to store,transfer and display marine data.This paper first presents the details of the main marine XML elements and then gives an example showing how to transform CTD-observed data into Marine XML format,which illustrates the XML encapsulation process of marine observed data.  相似文献   

13.
本文基于张家界市土地利用/土地覆盖变化,通过改进的生态系统服务价值与生态足迹的方法,测算了研究区域的生态补偿额度。研究表明:(1)从2001~2013年张家界市各县(区)生态系统服务价值变化率来看,永定区呈下降态势;增幅最大的是武陵源区,其次是桑植县,慈利县增幅最小。(2)2013年张家界市的人均生态足迹为1.3625 hm~2,而实际生态承载力为0.9556 hm~2,人均可利用生态承载力为0.8409 hm~2,则人均生态赤字为-0.5215 hm~2。(3)计算出了张家界市各县(区)的生态补偿标准,其中慈利县需要支付的生态补偿量最高,为18.61亿元;其次是永定区,为10.49亿元;再次是武陵源区,为582.12万元;最小的是桑植县,为359.70万元。评价结果将促进张家界市生态环境保护和经济社会的可持续发展。  相似文献   

14.
1INTRODUCTIONForestbiodiversityprovidesawiderangeofindirectbenefitstohumanbeing.Whiletheremaybelittlecon-sensusonwhetherthevariouselementsofforestbiodi-versitycanbevaluedineconomicterms, itisincreas-inglyrecognizedthatthesevaluesandtheroleofbio-diversityinmaintainingecologicalservicesareessen-tialtothehumankind.Thenotionofindirectusevalueofbiodiversityhasbeenassociatedwithaminimumlevelofecosysteminfrastructure, withoutwhichtherewouldnotbethegoodsandservicesprovidedbyit(FARNWORTHetal.,1…  相似文献   

15.
A Multi-channel Oceanographic Fluorescence Lidar (MOFL), with a UV excitation at 355 nm and multiple receiving channels at typical wavelengths of fluorescence from oil spills and chlorophyll-a (Chl-a), has been developed using the Laser-induced Fluorescence (LIF) technique. The sketch of the MOFL system equipped with a compact multi-channel photomultiplier tube (MPMT) is introduced in the paper. The methods of differentiating the oil fluorescence from the background water fluorescence and evaluating the Chl-a concentration are described. Two field experiments were carried out to investigate the field performance of the system, i.e., an experiment in coastal areas for oil pollution detection and an experiment over the Yellow Sea for Chl-a monitoring. In the coastal experiment, several oil samples and other fluorescence substances were used to analyze the fluorescence spectral characteristics for oil identification, and to estimate the thickness of oil films at the water surface. The experiment shows that both the spectral shape of fluorescence induced from surface water and the intensity ratio of two channels (I 495/I 405) are essential to determine oil-spill occurrence. In the airborne experiment, MOFL was applied to measure relative Chl-a concentrations in the upper layer of the ocean. A comparison of relative Chl-a concentration measurements by MOFL and the Moderate Resolution Imaging Spectroradiometer (MODIS) indicates that the two datasets are in good agreement. The results show that the MOFL system is capable of monitoring oil spills and Chl-a in the upper layer of ocean water.  相似文献   

16.
界定生态安全的概念需要将生态安全与环境保护、生态破坏、生态风险等相关概念进行甄别:保障生态安全与环境保护并非同一概念,生态安全立法规制的对象不仅仅针对生态破坏行为,实现生态安全的途径是对生态风险进行有效控制。与法的其他价值目标相比,生态安全是社会的"底座安全"因而成为法秩序的基本价值追求。将保障生态安全作为一种新的理念融入环境法体系,以赋予公众生态安全权为突破口,确认生态安全的实体性权能并落实公民的生态安全知情权、生态安全管理参与权、生态安全请求权等程序性权能,对公众的生态安全利益提供全面保护和制度化救济,是为我国生态安全立法的现实路径选择。  相似文献   

17.
【目的】研究提高船舶主机燃料的综合利用率。【方法】结合MAN 6S50ME型船舶柴油机的余热能量特性和循环热力过程特点,分别建立基本循环、缸套水预热循环和回热循环等三种船舶余热利用有机朗肯循环系统模型,对三种余热利用系统的热力性能与经济性能进行计算和分析。【结果与结论】在三种循环系统中,缸套水预热循环的综合性能更具优势,在循环压力为2000 kPa时,系统的综合性能达到最优,循环净功为555.35 kW,热效率可达18.27%,循环发电净收益提高39.64%。研究结果可为船舶柴油机余热利用系统的设计和优化提供一定的理论指导。  相似文献   

18.
With the using up of land resources, people are beginning to pay attention to the exploitation of the ocean and the use of marine resources is becoming more and more intense. Whether and how the ocean can be sustainably exploited as it is being exploited is an academic hot topic. This question is addressed in this paper based on the theories of carrying capacity of a marine region and marine eco-compensation, and the amount of the loss is calculated by the method of Time Value of Capital. This thesis covers the study of eco-compensation between two specific subjects with clear compensation objects, and as a defined approach and standard, the proposed method has good operability and positive practical significance in the good use of the ocean.  相似文献   

19.
斯里兰卡是海上丝绸之路沿线重要的节点国家,其周边海域生态环境变化与经济发展、休闲生活和食品安全密切相关。利用2002—2017年的MODIS遥感反演产品对斯里兰卡岛周边海域、关键节点港口科伦坡的生态环境参数年际变化规律分别进行分析和2003—2012年的MERIS遥感反射率产品对保克海峡进行水体类型时空分析,结论如下:① 研究区内光合作用有效辐射高值出现在马纳尔湾,海域沿岸浮游植物生物量相对较高,与海表温度负相关,外海浮游植物生物量极低,与透明度负相关。② 科伦坡港附近水温(海表温度)、海面光照强度(光合作用有效辐射)、水体清洁度(海水透明度)、海洋食物网基础的浮游植物生物量(叶绿素浓度)和浮游植物净初级生产力最大值分别出现在4月、3月、3月、8月、7月,致灾因素重点关注8月潜在的赤潮。③ 保克海峡浑浊带的源头是印度的卡里梅尔角,由高韦里河携带大量泥沙造成。这有助于了解和认识高时空变化的保克海峡及斯里兰卡周边海域在不同时间-空间的海洋生态环境。  相似文献   

20.
长江三角洲土地资源遥感动态分析   总被引:5,自引:2,他引:3  
对土地资源需求的增长与有限的土地资源量之间的矛盾 ,是长江三角洲区域经济持续发展的主要矛盾之一。随着长江三角洲区域经济的快速发展 ,城市化、工业化进程加快 ,土地资源在高强度的开发中发生快速变化。在经济发展的同时 ,人与土地资源的矛盾更加尖锐 ,成为当前制约国民经济持续、协调发展的重要因素。长江三角洲地区是我国经济高度发达的地区之一 ,也是我国历史上少有的大面积粮食高产、稳产区。本文在利用遥感和 GIS技术对 1985~ 2 0 0 0年间全区土地资源进行动态分析 ,特别是在对耕地资源数量的定量分析基础上 ,结合区域土地资源的结构变化特点 ,深入研究其时空过程及动态变化规律 ,探索长江三角洲地区耕地动态平衡的措施与土地资源合理利用的对策 ,为区域农业持续发展服务。  相似文献   

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