The Sediment Source and Transport Trends around the Abandoned Yellow River Delta,China

Sediment source and transport trends are influenced by various hydrodynamic factors, and thus play important roles in sedimentary evolution and coastal stability. To examine sediment transport trends around the abandoned Yellow River delta promontory and its erosion mechanism, we employ empirical orthogonal function (EOF) analysis to study sedimentary characteristics and transport trends of the abandoned Yellow River delta in northern Jiangsu Province, China. The results showed that: (1) the main sediment source in the abandoned Yellow River delta is the submarine coastal slope and both sides of the abandoned Yellow River Delta; (2) the main hydrodynamics controlling sediment transport is the current that runs along the shore, coupled with waves, especially southward currents; (3) the sediment of the study area was redistributed under hydrodynamics; coarse sediments were eroded and broadly transported to the south. Therefore, it is concluded that the sediment sources and transport have important influence on coastal evolution: the sediment source area shows mass loss of deposits and erosion; deposits in the submarine coastal slope provide the source and were continuously eroded to provide materials to other places as a sediment source.     

Spreading-rate dependence of hydroacoustic and teleseismic seismicity of ridge-transform systems: East Pacific Rise,Galapagos Ridge,and Mid-Atlantic Ridge

Seismicity in ocean ridge-transform systems reveals fundamental processes of mid-ocean ridges, while comparisons of seismicity in different oceans remain rare due to a lack of detection of small events. From 1996 to2003, the Pacific Marine Environmental Laboratory of the National Oceanic and Atmospheric Administration(NOAA/PMEL) deployed several hydrophones in the eastern Pacific Ocean and the northern Atlantic Ocean.These hydrophones recorded earthquakes with small magnitudes, providing us with...     

Distribution and invasion of Spartina alterniflora within the Jiaozhou Bay monitored by remote sensing image

Spartina alterniflora as an alien invasive plant, poses a serious threat to the ecological functions of the coastal wetland of the Jiaozhou Bay. As of 2019, the distribution area of S. alterniflora in the Jiaozhou Bay has reached more than 500 hm². For this reason, combined with field surveys, remote sensing monitoring of the invasion S.alterniflora in the Jiaozhou Bay has been carried out. To accurately identify S. alterniflora within the Jiaozhou Bay coastal wetland, we used a new m...     

基于构造演化分析的古近系储层预测:以辽西凸起中段沙河街组为例

辽西凸起中段古近系沙河街组缺乏规模性圈闭,储层横向变化快、预测难度大,滚动勘探一直难有较大突破.针对构造、储层问题,采用基于构造演化分析的古近系储层预测方法,综合运用裂变径迹构造反演和空间平衡剖面技术,开展构造演化精细分析,改变传统地层沉积模式,提出辽西凸起高部位发育沙河街组地层的新认识,指导构造解释调整,新增沙河街组...     

InSAR detection of residual settlement of an ocean reclamation engineering project: a case study of Hong Kong International Airport

Man-made land or islands that are reclaimed from the sea are suitable for building airports, harbors, and industry parks for material transportation because of their broad air and land spaces. However, the reclaimed foundation settlement process is of public concern, including the continuous impact of ocean processes on its stability. The majority of the buildings and facilities of Hong Kong International Airport (HKIA) are built on a reclaimed foundation. The reclaimed foundation has been in residual settlement since completion of the filling project in 1994. In this study, we use persistent scatterer interferometry (PSI) and ENVISAT (European Satellite) advanced synthetic aperture radar (ASAR) data to detect the residual settlement rates from 19 April 2006 to 9 January 2008. We use ground truth data to develop empirical correction models for correcting systematic biases in the ASAR PSI-detected settlement rates. The corrected data follow the Lorentz distribution well, implying that the residual settlement process is dominated by two modes or categories of settlement rates. The first category represents a relatively stable state and the second category represents a continuous settlement state. A ground settlement rate map of HKIA shows that an area of the Passenger Terminal Building and an area of the Southern Runway are two relatively stable areas. There are two major continuous settlement areas. One covers the airport Midfield. Another is along the coastline, implying that attention should be paid to impacts of ocean processes on the stability of airport foundations.     

中国对虾(Penaeus chinensis)幼体血液循环的活体观察

溞对中国对虾早期幼体的循环系统及血液流向进行了活体观察 ,描述了中国对虾早期幼体发育阶段中幼体循环系统血管的走向与分布、血液的流向及循环路径等 ,比较各期幼体循环系统的形态 ,并探讨对虾早期幼体循环系统的发育过程。     

黄条鰤贮藏挥发性化合物的研究

用气相色谱仪和气—质联机等方法对黄条鱼师的腐败挥发性化合物进行了定性和定量分析。这将有利于对黄条做一步的生化性质分析和制定其鲜品的国家标准。样品在２５℃贮藏５ｄ期间，测定了某些化学指标。结果表明在贮藏１ｄ后，鱼肉变腐臭，挥发性碱基化合物三甲胺和二甲基在贮藏中增加。在５ｄ的贮藏期间发现的挥发性有机酸包括乙酸、丙酸、丁酸、异丁酸、戊酸、异成酸，并且它们的含量不断增加，检测出脂肪氧化产物和含硫化合物，正己醛、３—辛酮、３，５—丰二烯—２—酮，２—壬酮辛烯—３—醇，二甲基三硫化物、１Ｈ—吲哚等都是黄条腐败时产生的重要挥发性化合物。应指出的是，２—甲基丁醇、庚醇、苯酚、辛烯—３—醇己醛是黄条中所特有的化合物，其余化合物与其它鱼类的挥发性化合物几乎相近。     

自由投放式声学多普勒海流剖面观测及数据处理

自由投放式声学多普勒海流剖面（FADCP）观测以“自由落体”方式进行采样,其不依赖于测船钢缆牵引即可对全深度海流进行观测,观测稳定性较下放式声学多普勒海流剖面（LADCP）大幅提升,有效减少了观测值之中的不规则运动。2021年4月与9月在南海西沙海域开展的FADCP观测实验获得了两个断面包含16个站的海流及CTD资料。基于静置期间的真实底流观测,各站全深度的海流剖面采用剪切法获得,潜标附近站位剖面与潜标观测剖面相比,平均流速偏差为3 cm/s。观测断面捕捉到了西沙海域两个时期的气旋涡,其垂直结构比HYCOM模拟更精细,表层流与绝对地转流契合。研究表明,FADCP对测船要求低、数据质量高,其后处理简便且结果良好,但无法对特定水层实施补充观测。     

起伏海面的雷电电磁场传播特征及其对闪电定位精度的影响

为了研究起伏海面对雷电电磁传播的影响,本文利用Barrick表面阻抗理论和Wait近似算法,采用改进二维分形海面模型模拟起伏海面,利用数值模式,分析起伏海面的雷电电磁传播特征,并进一步讨论了起伏海面对时差法闪电定位系统定位精度的影响。结果表明:起伏海面对垂直电场和磁场的峰值的影响不显著,但会引起波形的上升期时间的延长,浪高越大,影响越明显;随着观测距离的增加,雷电垂直电场波形的上升时间逐渐变长;风速的变化与雷电垂直电场波形的上升时间成正比;由于海面起伏引起雷电电磁场波形在传播中的变化会影响基于时差法闪电定位系统的定位精度,定位误差可达几至十几公里。     

沉积物粒度组分空间预测的神经网络残余kriging方法

针对近海表层沉积物粒度组分空间变异的尺度差异性,提出了基于广义回归神经网络残余kriging的沉积物粒度组分空间预测方法,并以海州湾沉积物粒度数据为基础,分析了其在沉积物粒度组分空间预测和底质类型制图中的应用效果。结果表明,广义回归神经网络残余kriging方法能够获得比普通kriging方法更高的沉积物粒度组分空间预测精度,并且其底质类型的总体空间预测精度达到85%以上,相应的Kappa系数也在0.8以上,显示底质制图的预测类型与样本的实测类型具有较高的一致性。新方法对于开展定量化的沉积物粒度组分空间预测和底质类型制图具有参考价值。