厦门港刘五店航道海域溢油扩散数值模拟   总被引：2，自引：0，他引：2  

许婷 《海洋学研究》2011,29(1):90-95

利用MIKE 21 HD模块建立了厦门湾二维水动力模型,经2008年最新实测资料,验证了模型的可靠性和适用性,模拟结果为厦门湾刘五店航道二维溢油模型的建立提供水动力基础数据.利用MIKE21 SA模块建立厦门湾刘五店航道二维溢油模型,应用"油粒子"模型模拟输移、风化和热量迁移等过程,对刘五店航道一期工程溢油泄露事故进行...  相似文献   

Resource-based view of sustainability engagement     

《Global Environmental Change》2015

This research examines local sustainability planning processes under the label of Local Agenda 21 in Italy from a resource-based view. Two types of resources, municipal (or internal resources) and relational resources, are considered. Relational resources stem from (1) dyadic relationships with higher levels of government and (2) network relationships (municipality-higher level of government-municipality). A model is proposed in which the integration of these resources explains the engagement of municipal authorities with Local Agenda 21-type processes. The model is tested by considering the perceptions of 108 local senior officials and politicians who are in charge of Local Agenda 21 processes in Italy. The respondents account for 31% of the members of a formal Italian Local Agenda 21 network. The results show moderate to low engagement with Local Agenda 21 processes, which is explained by moderate to poor levels of relational resources. Our findings indicate that local authority engagement with Local Agenda 21-type processes requires a systemic perspective, where higher levels of government and municipalities integrate and combine their resources and create new purposefully led resources through regular and intense interactions.  相似文献   

Assessing hydrological model predictive uncertainty using stochastically generated geological models          下载免费PDF全文

Xin He  Anker Lajer Højberg  Flemming Jørgensen  Jens Christian Refsgaard 《水文研究》2015,29(19):4293-4311

In distributed and coupled surface water–groundwater modelling, the uncertainty from the geological structure is unaccounted for if only one deterministic geological model is used. In the present study, the geological structural uncertainty is represented by multiple, stochastically generated geological models, which are used to develop hydrological model ensembles for the Norsminde catchment in Denmark. The geological models have been constructed using two types of field data, airborne geophysical data and borehole well log data. The use of airborne geophysical data in constructing stochastic geological models and followed by the application of such models to assess hydrological simulation uncertainty for both surface water and groundwater have not been previously studied. The results show that the hydrological ensemble based on geophysical data has a lower level of simulation uncertainty, but the ensemble based on borehole data is able to encapsulate more observation points for stream discharge simulation. The groundwater simulations are in general more sensitive to the changes in the geological structure than the stream discharge simulations, and in the deeper groundwater layers, there are larger variations between simulations within an ensemble than in the upper layers. The relationship between hydrological prediction uncertainties measured as the spread within the hydrological ensembles and the spatial aggregation scale of simulation results has been analysed using a representative elementary scale concept. The results show a clear increase of prediction uncertainty as the spatial scale decreases. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Shoreline spatial and temporal response to natural and human effects in Boujagh National Park,Iran     

Morteza Karimi  Jamal Mohammad Vali Samani  Mehdi Mazaheri 《国际泥沙研究》2021,36(5):582-592

Shoreline variation and river deltas are among the most dynamic systems in marine environments. The related different variations in spatial and temporal scales play significant roles in land planning and different management applications. Modeling the dynamics of seashore of Boujagh National Park (BNP) which is located on the southern coast of the Caspian Sea in the Sefidrud Delta (SD), considering natural and anthropogenic factors, was the main objective of the current study. To achieve this goal, a combination of remote sensing data, historical data, and numerical simulations was utilized. The BNP covers an area of 3,270 ha and includes two international wetlands, Boujagh and Kiashahr. In earlier periods, this area faced severe morphological changes whereas recently its shoreline has experienced gradual variations. Accordingly, at the first stage, the shoreline variation from 2006 to 2017 was extracted by processing and classifying Operational Land Imager (OLI) and Thematic Mapper (TM) images from Landsat satellites using the Maximum Likelihood approach. In the second stage, the two dimensional MIKE21 model was utilized to identify wave and coastal current patterns and parameters for the year 2015. Morphologically, the results showed that, the shoreline of the BNP is affected by several natural and anthropogenic factors. Seaward advancement of the shoreline occurred in zones A (east zone) and C (west zone) due to Caspian Sea Level drop and sedimentation while retreating occurred at Zone B (north zone) influenced by wave and current patterns and reduction of the Sefidrud River flows. Also, the results imply that maintaining the existing conditions results in the disappearance of a considerable part of the ecological area in the BNP. Hence, to manage and preserve the coastline of the BNP complying with the current anthropogenic and natural factors, it is vital to take necessary management measures.  相似文献   

基于Boussinesq波浪模型的港池波浪数值模拟与泊稳分析          下载免费PDF全文

吴亚楠  武贺  周庆伟  马勇 《海洋通报》2021,(3)

基于Boussinesq方程的MIKE21-BW模型,建立等水深、双突堤式的波浪数值港池,采用不同的波浪入射方向和双突堤口门宽度,分别对波浪经双突堤后的绕射情况进行模拟。根据《港口与航道水文规范》中的计算参数和突堤绕射系数结果,对BW模型进行率定和验证,结果表明二者吻合度较好,可以较好地描述港池的泊稳状况。在此基础上,利用MIKE21-BW模型对秦皇岛某港口防波堤工程的不同布局方案进行模拟计算和泊位稳定性分析,提出了工程设计方案建议。  相似文献   

基于MIKE 11的北京市典型区域降雨径流特征研究     

梁灵君  杨忠山  刘超 《水文》2012,(1):39-42,28

以北京城市化发展区凉水河大红门闸控制流域为典型区域,在分析区域20世纪80年代到2000年后下垫面变化特征的基础上,结合区域同时期的降水和径流资料,采用MIKE11软件中的UR-BAN模块构建流域降雨径流模型,以流域模拟流量和实测流量拟合效果最佳为原则,利于多场次的实测降水进行降雨径流的模拟分析,研究区域城市化发展对水文特性变化的影响。  相似文献   

黑龙江二十一站-宝兴沟( 铜) 金矿床特征及其热液成矿系统     

张纯歌  李庆录  宋贵斌  张春辉 《世界地质》2012,31(3):505-514

二十一站-宝兴沟( 铜) 金矿床( 点) 位于上黑龙江断陷盆地的东南部。区域地质背景及典型矿床研究表明,矿床不仅受NE 向断裂构造控制,还受其同期的岩浆岩控制。对宝兴沟金矿床的流体包裹体测试结果、矿床围岩蚀变和与火山穹窿构造间的关系等研究,表明宝兴沟金矿可能是中硫型浅成低温热液型矿床,二十一站和十五里桥( 铜) 金矿床可能是高硫型浅成低温热液型矿床( 点) 。区域地质特征、遥感解译、航磁异常及Au、Ag、Cu 化探异常分布特征显示了本区可能存在两种环境的斑岩型--浅成低温热液型成矿热液系统。在此基础上,结合铜元素化探异常和火山穹窿等特征,提出了在十五桥金矿床、二十一站铜金矿一带寻找斑岩型铜钼矿化类型,在NW、NNE 向构造带内找寻与浅成低温热液系统有关的矿床。  相似文献   

晋县凹陷未熟蒸发岩沉积物中C22-C27甾烯和C24-C30四环萜烷的检出     

陈腾水  徐忠辉  刘菊  卢鸿  盛国英  彭平安  Kliti Grice  Paul Greenwood 《地球化学》2009,38(3):289-298

晋县凹陷赵芯2井（2459m,Ezk）低熟蒸发岩样品中检出了异常分布的C22-C27甾烯和C24-C30四环萜烷（17,21-断藿烷）,但在同井更深、成熟度相对更高的沉积物中并未检出。实测镜质组反射率R^0=0．43％以及芳烃馏分中有高丰度的苯并噻吩和多烷基化的二苯并噻吩,说明热催化作用成因是不可能的,微生物参与成为最可能的生成途经。沉积抽提物未显示出常规生物降解的痕迹,因此这些化合物很可能是在早期成岩阶段特定微生物作用的结果。该区油样中检出的C21-C29甾烷的特征与同时检出的C22-C27甾烯特征一致,进一步表明微生物作用的可能性;高丰度的C24-C30四环萜烷（17,21-断藿烷）和常规藿烷、甲基藿烷相匹配,以及高丰度的C22-C27甾烯和规则甾烷缺失相匹配,特别是芳烃馏分中多取代二苯并噻吩类有机含硫化合物的检出,均表明异常分布的C22-C27甾烯与C24-C30四环萜烷类似,很可能是早期成岩阶段微生物改造作用下的产物。  相似文献   

进入21世纪的中国农业气象研究   总被引：9，自引：0，他引：9  

王春乙  张雪芬  孙忠富  吕厚荃  潘学标 《气象学报》2007,65(5):815-824

文中简要回顾了中国农业气象的发展历程,并将现代农业气象研究划分为3个阶段:20世纪50—60年代初创起步阶段、70—80年代恢复发展阶段及90年代以后的快速发展阶段。从作物资源利用、农业气候资源与区划研究、作物产量预报和遥感估产技术、农业气象灾害研究、气候变化对农业与生态影响研究等方面重点介绍了现代农业气象科研工作的主要研究成果和进展;从未来气候变化带来的问题、农业生产和可持续发展需求、农业气象科研中存在的薄弱环节等方面,提出了气候变化影响下农业气象灾害防灾减灾技术研究、气候资源高效利用技术研究、有关国家粮食安全关键技术研究、农业气象现代化观测技术研究、作物生态系统模拟与定量化评估技术研究、设施与特色农业气象及现代生物技术的环境调控技术研究、农业气象基础理论研究等方面农业气象未来的重点研究领域和发展方向。  相似文献   

2010—2100年淮河径流量变化情景预估   总被引：2，自引：0，他引：2       下载免费PDF全文

高超  曾小凡  苏布达  闻余华  朱进  吴必文 《气候变化研究进展》2010,6(1):15-21

根据淮河流域14个气象站点1964—2007年观测降水量与温度数据和ECHAM5/MPI-OM模式在3种排放情景下对该流域2001—2100年的气候预估,利用人工神经网络模型预估淮河蚌埠站2010—2100年逐月径流量变化。计算结果表明:3种排放情景下2010—2100年淮河径流量年际变化幅度差异较大,SRES-A2情景总体处于波动上升趋势,其中2051—2085年上升趋势显著;SRES-A1B情景2024—2037年年平均流量显著降低;SRES-B1情景年平均流量的变率甚小。季节分析表明:春季径流量在2010—2100年变幅最小,距平百分率在-15.1%～18.6%之间小幅波动。夏季平均流量在2040年代前呈下降趋势,之后小幅波动上升。秋、冬季平均流量SRES-A2和SRES-A1B情景变幅显著,其中,秋季SRES-A2情景2060年代距平百分率下降达50.6%,为3种情景下各季节径流量降幅之最;冬季SRES-A1B情景2050年代其增幅达到54.7%,亦为上升幅度之最。  相似文献