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31.
于1997年6月-1998年5月用现场方法测定了烟台四十里湾海区总颗粒物质(TPM)、颗粒有机物(POM)现存量和栉孔扇贝同化率(AE)周年变化,并分析栉孔扇贝同化率与海区温度、盐度、TPM和POM的关系。结果表明,(1)整个海区TPM现存量秋季最高,其次为春季和冬季,夏季最低;海区POM含量变化不大,在1.34-1.65mg/L之间;栉孔扇贝同化率在春、夏、秋三了较高,冬季较低,其中在秋末冬初(  相似文献   
32.
北部湾潮致、风生和热盐余流的三维数值计算   总被引:7,自引:2,他引:7  
基于二阶湍流闭合模型计算涡动粘性系数的POM三维水动力模式,研究采用细网格,考虑了6个岛屿的影响,海底磨擦系数进行划片取值,把作为强迫力的潮汐、风力和热盐统一在一个模型中,诊断计算并获得了北部湾三维潮致-风生-热盐余流。用实测资料对计算结果进行了验证,显示了本研究结果的合理性。同时给出了潮致余流、风生流和热盐余流,并且对各因子的作用做了比较和分析,结果表明风生流占主要成分。  相似文献   
33.
基于POM(Princeton Ocean Model)海洋模式,对南海不同深度环流的季节性变化进行了数值模拟研究。模拟结果表明:南海表层和上层环流受季风影响,在夏季西南季风驱动下,南海表层环流在南部呈现强反气旋式结构,在南海北部则是一个弱的气旋环流;在冬季东北季风驱动下,南海表层环流结构呈气旋式,并且明显加强了沿越南沿岸向南流动的西边界流;春季和秋季为南海季风的转换期,其对应的环流特征也处于冬季环流与夏季环流的过渡流型,流速与冬季和夏季相比较弱。南海200m层环流的季节变化与表层相似。在500与1 000m层,则出现许多处中尺度漩涡,流场也变得较为紊乱。  相似文献   
34.
基于三维全动力POM海洋模式,根据2008年6月1日海监飞机监测绿潮所在位置,采用拉格朗日粒子追踪法反向积分,追溯绿潮来源。数值模拟结果显示,回溯至5月中旬,绿潮主要来源于黄海南部江苏连云港和盐城近海海域。黄海绿潮溯源数值模拟,为政府相关部门了解绿潮的源头,并采取相应的措施提供依据,进而为保护生态环境、防灾减灾做贡献。  相似文献   
35.
INTRODUCTIONInearly 1 96 0’s,thetideandtidalcurrentintheBeibuGulfwereobservedandanalysedbyChinaincooperationwithVietnam1) .ThesystematicstudiesoftideandtidalcurrentintheBeibuGulfwerefirstcarriedoutbyFang (1 986 ) .Thehistoryofnumericalstudyoftideandtidalcurrent…  相似文献   
36.
广西近海海水溶质稀释扩散现场实验与COD潮扩散数值模拟   总被引:1,自引:0,他引:1  
海水的稀释扩散是一个十分复杂的问题.在近岸海域,弯曲的海岸线、不同的水深、变化的天气、随机的海浪和周期性的潮汐潮流都对海水的扩散产生直接影响.Joseph和Sendner[1],Okubo[2],及国内的张法高[3]、李培泉[4]、周家义[5]、姜太良[6]等进行了现场实验或数值方面的研究.1992~1996年,我们对广西近海海洋环境进行了8个航次的综合调查,并在广西廉州湾和铁山港进行了数次海水稀释扩散现场实验.  相似文献   
37.
半封闭高密度筏式养殖海域水动力场的数值模拟   总被引:9,自引:0,他引:9  
基于2006年4月和7月在中国北方典型筏式养殖海域--桑沟湾的潮流特征的观测,对养殖设施(筏架与浮子等)和养殖生物(海带等)带来的阻力分别进行参数化,修改POM模型,对桑沟湾水动力场进行模拟,进而以此水动力模型驱动水质模型模拟该湾半交换时间,并与不考虑养殖阻力的模拟结果进行比较.结果表明:(1) 加入养殖阻力的水动力模型能模拟出更加真实的潮流流速大小和垂直结构特征,即筏式养殖活动带来的潮流上边界层的存在.(2) 由于养殖活动的影响,桑沟湾的流速减小40%,平均半交换时间延长71%.因此,如果忽视养殖活动本身对海水流动的阻碍作用,会高估桑沟湾的流速大小,高估营养盐和颗粒物的更新补充速度,进而影响对该养殖海域的养殖容纳量的评估.  相似文献   
38.
According to the earlier international studies on the coupled ice-ocean model and the hydrology, meteorology, and ice features in the Bohai Sea, a coupled ice-ocean model is developed based on the National Marine Environment Forecast Center's (NMEFC) numerical forecasting ice model of the Bohai Sea and the Princeton ocean model (POM).In the coupled model, the transfer of momentum and heat between ocean and ice is two-way, and the change of ice thickness and concentration depends on heat budget not only at the surface and bottom of ice, but also at the surface of open water between ices. The dynamic and thermodynamic coupling process is expatiated emphatically. Some thermodynamic parameters are discussed as well.  相似文献   
39.
Peatlands cover a very small area of the Earth, but store globally significant quantities of carbon and export disproportionate quantities of fluvial organic carbon, especially when the peatlands are degraded or disturbed. Peatland headwater catchments with high concentrations of dissolved and particulate organic carbon (DOC and POC) provide an opportunity to investigate the possibility of competing effects that could lead to enhanced or diminished turnover of DOC in the presence of POC. Both POC and DOC can be degraded by light and microbes, producing smaller molecules and releasing CO2 and CH4 to the atmosphere, and POC can inhibit light penetration, stabilize DOC by providing adsorption sites and providing surfaces for microbes to interact with DOC. However, the majority of peatland fluvial carbon studies are conducted using filtered water samples, and measure only the DOC concentration, so the impact of the particulate organic matter (POM) on in-stream processing of organic carbon is relatively unknown. It is therefore possible that studies have underestimated carbon transformations in rivers as they have not considered the interaction of the particulate material on the dissolved concentrations; there could be higher losses than previously estimated, increasing the contribution of peatland headwaters to GHG emissions. In this study, we assessed if the current approach of DOC degradation studies accurately represent the impact of POM on DOC degradation, by quantifying DOC production from POM, and therefore POC, over time in water with manipulated POM concentrations. Both filtered and unfiltered water lost 60% of the DOC over 70 hours, whereas the treatment with additional POM lost only 35%. The results showed that filtering does not significantly impact the DOC degradation rates; however, when the POC concentration was doubled, there was a significant reduction in DOC degradation, suggesting that filtering would still be necessary to get accurate rates of DOC transformations in waters with high POC concentrations.  相似文献   
40.
基于虚拟偏移距方法的各向异性转换波保幅叠前时间偏移   总被引:1,自引:1,他引:1  
In this paper, we use the method of pseudo-offset migration (POM) to complete converted wave pre-stack time migration with amplitude-preservation in an anisotropic medium. The method maps the original traces into common conversion scatter point (CCSP) gathers directly by POM, which simplifies the conventional processing procedure for converted waves. The POM gather fold and SNR are high, which is favorable for velocity analysis and especially suitable for seismic data with low SNR. We used equivalent anisotropic theory to compute anisotropic parameters. Based on the scattering wave traveltime equation in a VTI medium, the POM pseudo-offset migration in anisotropic media was deduced. By amplitude-preserving POM gather mapping, velocity analysis, stack processing, and so on, the anisotropic migration results were acquired. The forward modeling computation and actual data processing demonstrate the validity of converted wave pre-stack time migration with amplitude-preservation using the anisotropic POM method.  相似文献   
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