Field experiments of multi-channel oceanographic fluorescence lidar for oil spill and chlorophyll-a detection     

Xiaolong Li  Chaofang Zhao  Youjun Ma  Zhishen Liu 《中国海洋大学学报(英文版)》2014,13(4):597-603

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   

浅谈雷电灾害的调查与鉴定     

陈健 《气象研究与应用》2014,(1):104-106

通过对广西雷灾调查鉴定的现状的分析,找出雷电灾害调查工作存在的不足,提出加强雷灾事故调查鉴定能力建设的对策.  相似文献   

一次春季黄海海雾和东海层云关系的研究   总被引：2，自引：1，他引：1  

张苏平  刘飞  孔扬 《海洋与湖沼》2014,45(2):341-352

结合多种观测数据和数值模拟结果对2011年3月12—13日的一次黄海海雾过程进行分析。观测数据分析表明:此次黄海海雾过程与东海层云之间存在密切的联系。地面高低压位置为水汽从层云区向北输送提供了有利的环流条件;黄海上空天气尺度下沉运动,加强了海洋大气边界层(MABL)层结的稳定性,MABL顶自南向北高度降低,有利于水汽在向北输送过程中不断向海面聚集;下沉导致的干层以及逆温层对海雾的发生发展起重要作用。模式结果进一步证明天气尺度下沉运动与MABL内的下沉在29°—30°N附近同位相叠加,使得该海区上空的下沉运动明显增强,边界层高度迅速下降。下沉可能会导致气块温度升高,云滴蒸发,来自层云区的水汽随流场向北向下输送逐渐接近冷海面凝结成雾,近海面水汽的平流输送使海雾进一步向北发展。本研究为海雾预报提供新的参考思路。  相似文献   

南黄海磁性基底特征分析和综合解释     

邢涛  张训华  张向宇 《海洋与湖沼》2014,45(5):946-953

本文利用南通幅区域地质调查的重磁异常数据,在重磁异常特征分析的基础上,采用一维频谱分析法对南黄海进行磁性基底反演。结果表明:南黄海属于扬子块体向海域的延伸,具有元古代结晶基底和古生代褶皱基底的双基底结构,其磁性基底深度在2—10km之间变化,是褶皱基底与磁性层最小埋深的结合,在坳陷和隆起上表现不同。通过利用综合地质和地球物理综合方法,对南黄海区域的四大构造单元华北—狼林地块、扬子—京畿地块、华南—岭南地块、东海大陆架进行重磁异常变化特征和磁性基底特征分析,为研究区断裂等区域构造特征解释提供了依据。  相似文献   

胶州湾沉积物中有机硫来源及成因机制的研究     

黄香利  朱茂旭  陈良进  李铁 《海洋学报》2014,36(6):50-57

有机硫是海洋沉积物中重要的硫形态,其中成岩有机硫对有机质保存和微量元素形态具有重要影响。利用化学提取及硫稳定同位素研究了胶州湾沉积物中碱可提取的腐殖酸硫(HA-S)、富里酸硫(FA-S)以及铬不可还原有机硫(non-CROS)的垂直分布、来源及形成机制。结果表明,non-CROS、HA-S以及FA-S的含量范围分别为19.1~52.6、3.35~7.82和27.3~38.6μmol/g,均处于其他许多近海沉积物中含量的低值区,且3者均为海洋生物有机硫和成岩有机硫的混合物。HA-S和nonCROS以海洋生物有机硫为主,其份数分别为65%~68%和67%~77%,而FA-S则以成岩有机硫为主(54%~73%)。相对于生物有机硫,成岩有机硫更易被碱和酸性Cr(Ⅱ)溶液提取,因此腐殖质硫和non-CROS都不能全面反映沉积物中有机硫的组成和来源。黄铁矿和腐殖质中成岩有机硫含量随深度的同步增加表明黄铁矿形成并未明显地竞争性抑制有机质硫化。  相似文献   

Can management effort be predicted for marine protected areas? New considerations for network design     

《Marine Policy》2014

This study examined the level of management complexity (simultaneously occurring licensed human activities) within the currently designated Marine Protected Areas (MPAs) in Scottish waters and through modelling and statistical analysis determined which variables play an important role in defining the level of management effort required for each MPA. This study utilised surveyed distribution data for Priority Marine Features and modelled distribution data showing potential “Most Suitable” Priority Marine Feature habitat through the species distribution model, Maxent. Prediction indicators were developed through Spearman׳s Rank coefficients and a linear regression model. Results showed that, (1) there was a significant negative correlation between the management complexity score within 5 km of a MPA and the number of casework events (defined as any work or statutory consultation associated with an MPA, such as planning applications, discharges or new fisheries); and (2) a significant positive correlation between the number of casework events and location, number of features, and the type of features and most suitable scores. Calculations showed that Lochs Duich, Long and Alsh, Loch Sunart, Loch Sween and Loch Creran may potentially require most effort to manage once they are designated as MPAs. This study showed that it is possible to evaluate options within an MPA network to achieve cost effective options for the biodiversity and socio-economic objectives of MPA networks and that some MPAs are likely to be more efficient than others in terms of management time.  相似文献   

Marine governance of European Seas: Introduction     

《Marine Policy》2014

This introduction explains the context and structure of a block of articles developed as part of the governance work packages of the FP7 project: “Options for Delivering Ecosystem-based Marine management” (ODEMM).  相似文献   

Consolidation and creep behaviors of two typical marine clays in China   总被引：2，自引：1，他引：1  

蒋明镜  刘静德  尹振宇 《中国海洋工程》2014,28(5):629-644

This paper presents an experimental investigation into the deformation characteristics of two typical marine clays obtained from Dalian and Shanghai, respectively, in China. Three kinds of laboratory tests, i.e. conventional oedometer tests, one-dimensional and triaxial creep tests were carried out. The results obtained from consolidation tests demonstrate linear v e ？ log？ relationships for Shanghai clay at normally consolidated state, while partly or even global non-linearrelationships for Dalian clay. The compression index c C for both clays follows the correlation of Cc=0.009（WL-10）where WL is the liquid limit of soil. The relationship between v log Kv （ Kv is the hydraulic conductivity of soil） and voidratio e is generally linear and the hydraulic conductivity change index kv C can be described by their initial void ratio forboth clays. The secondary compressibility of Dalian clay lies in medium to high range and is higher than that of Shanghaiclay which lies in the range of low to medium. Furthermore, based on drained triaxial creep tests, the stress-strain-timerelationships following Mesri＇s creep equation have been developed for Dalian and Shanghai clays which can predict thelong-term deformation of both clays reasonably well.  相似文献   

2011年南黄海辐射沙脊群海域浮游植物种类组成和密度的时空变化     

魏永杰  李伯康  曹维  蔡燕红  黄秀清  费岳军 《台湾海峡》2014,(2):190-197

于2011年2～12月,在南黄海辐射沙脊群海域设置6个采样站位,每逢双月份调查1次,研究该海域浮游植物密度及优势种的时空变化.调查共获得浮游植物87种,以硅藻种类最多.浮游植物密度呈周年双峰变化,分别在4月和8月成峰,4月峰值最大,水样浮游植物平均密度为1.59×104cells/dm3,网样浮游植物平均密度为2.71×106cells/m3,8月峰次之,水样浮游植物的平均密度为1.28×104cells/dm3,网样浮游植物平均密度为7.38×105cells/m3;浮游植物密度在2月和4月,北高南低,6月和8月中部高,外围较低,10月和12月南部高北部低.2月和4月,中肋骨条藻（Skeletonema costatum）为第一优势种,6月和12月虹彩圆筛藻（Coscinodiscus oculus-iridis）为第一优势种,8～10月琼氏圆筛藻（Coscinodiscus jonesianus）为第一优势种,枯水期（2月）铁氏束毛藻（Trichodesmium thiebautii）在局部海域形成优势.  相似文献   

东山湾表层沉积物5种重金属元素含量分布及其与主要环境因子的关系     

郑盛华  杨妙峰  席英玉  陈宇锋  蔡建堤  陈财珍  钟硕良 《台湾海峡》2014,(2):251-257

根据2011年8月福建东山湾12个站位表层沉积物中5种重金属含量调查,探讨了它们的分布趋势、相互关系、影响因素,并运用潜在生态风险指数法对重金属污染进行风险评价.结果表明,该海域表层沉积物中重金属Cu含量变化范围在5.53～22.40 mg/kg之间,平均值为15.10 mg/kg;Pb含量变化范围在28.9～42.6 mg/kg之间,平均值为35.0 mg/kg;Zn含量变化范围在34.8～133.9 mg/kg之间,平均值为95.9 mg/kg;Cd含量变化范围在0.031～0.078 mg/kg之间,平均值为0.059 mg/kg;Cr含量变化范围在19.2～91.8 mg/kg之间,平均值为62.5 mg/kg.重金属含量的分布呈现湾顶（3、11号站）高、湾外（7号站）低的格局;沉积物中有机质对重金属含量的分布起着重要作用;重金属Cu、Zn和Cr的含量随着沉积物粗颗粒组分（63～2 000μm）含量的增大而降低,成负相关关系（p〈0.05）;Cr的含量随着粘土组分（〈1μm）含量的增大而增大,成正相关关系（p〈0.05）.除了湾顶3号站Cr（含量为91.8 mg/kg）以外,其他重金属元素含量均符合《海洋沉积物质量》一类标准;各元素潜在生态危害系数Ei r大小顺序为Cd〉Pb〉Cu〉Cr〉Zn,所有站位重金属潜在生态危害指数RI均远小于90,属低度生态风险,表明东山湾沉积环境基本良好.  相似文献