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951.
952.
953.
A class of coupled system of the E1 Ni(n)o/La Ni(n)a-Southern Oscillation (ENSO) mechanism is studied. Using the perturbed theory, the asymptotic expansions of the solution for ENSO model are obtained and the asymptotic behavior of solution for corresponding problem is considered. 相似文献
954.
955.
With the development of modern oceanic observation technologies,coastal survey data have been experiencing a substantial growth.The integration management of the data from different disciplines,different sources and different formats has become a major research field in coastal geomorphology by using Geographic Information System (GIS).This paper puts forward a new methodology framework of GIS techniques in coastal ocean geomorphology,including data acquisition,process,analysis,and representation.It focuses on some major GIS techniques to study the land-ocean interaction mechanism,such as spatial analysis,submarine topography model and three-dimension (3D) visualization,and apply its result to coastal urban planning,harbor site selection and geomorphology environment about coral reef and islands on the continental shelf.The case studies cover the whole coastal ocean to serve the social community,economical development and diplomatic rights for decision-making all round in the coastal zone.The research shows clearly that the application of coastal multi-source geospatial platform has changed the traditional coastal geomorphology science dramatically from its research scope,fields and methods,however,as made clear in this paper,extracting accurate information from remote sensing data and GIS databases for coastal geomorphological applications is a nontrivial challenge that requires the combined knowledge and skills of information scientists and geomorphologists. 相似文献
956.
Multivariate analysis of fluorescence and source identification of dissolved organic matter in Jiaozhou Bay, China 总被引:1,自引:0,他引:1
Hierarchical clustering analysis and principal component analysis (PCA) methods were used to assess the similarities and dissimilarities of the entire Excitation-emission matrix spectroscopy (EEMs) data sets of samples collected from Jiaozhou Bay, China. The results demonstrate that multivariate analysis facilitates the complex data treatment and spectral sorting processes, and also enhances the probability to reveal otherwise hidden information concerning the chemical characteristics of the dissolved organic matter (DOM). The distribution of different water samples as revealed by multivariate results has been used to track the movement of DOM material in the study area, and the interpretation is supported by the results obtained from the numerical simulation model of substance tracing technique, which show that the substance discharged by Haibo River can be distributed in Jiaozhou Bay. 相似文献
957.
Mohamed Ali Kalefa El-Ghali Sadoon Morad Howri Mansurbeg Miguel Angel Caja George Ajdanlijsky Neil Ogle Ihsan Al-Aasm Manhal Sirat 《Marine and Petroleum Geology》2009
Sequence stratigraphy of fluvial deposits is a controversial topic because changes in relative sea level will eventually have indirect impact on the spatial and temporal distribution of depositional facies. Changes in the relative sea level may influence the accommodation space in fluvial plains, and hence have impact on types of fluvial system, frequency of avulsion, and style of vertical and lateral accretion. This study aims to investigate whether depositional facies and changes in the fluvial system of the Lower Triassic Petrohan Terrigenous Group sandstones (NW Bulgaria) in response to changes in the relative sea level have an impact on the spatial and temporal distribution of diagenetic alterations. 相似文献
958.
Validation of the AZTI's Fish Index (AFI), proposed for the Basque Country (northern Spain), in assessing fish quality within the Water Framework Directive (WFD), is undertaken. The response to anthropogenic pressure is investigated, in setting the boundaries between the different quality status classes. Hence, 12 estuaries were sampled, at different frequencies, between 1989 and 2007, by means of a beam trawl. Significant (p < 0.0001) correlations were found between the AFI and oxygen saturation and ammonia. Oxygen quality standards are used to set boundaries between quality classes. Then, the AFIs obtained are compared with different anthropogenic pressures, including urban and industrial discharges, engineering works and dredging. The effects of the removal of some of these pressures are also studied. The total number of pressures within an estuary shows significant (p < 0.009) negative correlation with AFI, explaining between 51 and 62% of the variability in fish quality. The impact of pressures upon fish and demersal assemblages is detected as required by the WFD. Nonetheless, further investigation and intercalibration of the methods used, are necessary. 相似文献
959.
Jrg Aßmus Webjrn Melle Dag Tjstheim Martin Edwards 《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(21-22):1895
The plankton abundance data of the Continuous Plankton Recorder (CPR) route from Bergen or Rotterdam to Weather Station Mike (6444′N, 2E) from 1949 to 1981 were analysed for long-term trends and seasonal production cycles, and were related to environmental data. The data were explored using the canonical correlation analysis and nonparametric techniques like the Nadaraya–Watson regression. While large copepods such as Calanus spp. and Metridia lucens did not show any temporal trends, a sharp decrease in the abundances of smaller copepods and phytoplankton was observed after 1960. The temporal trends were not related to the NAO, but did show a correlation with the wind direction. Seasonal abundance curves showed that production of both phytoplankton and zooplankton taxa started earlier in coastal water compared to Atlantic water. From the 1950s to the 1970s most taxa showed a delay in the start of the seasonal production cycles, indicating a reduction in the length of the productive cycle. This may to some extent explain the reduced abundance of smaller copepods, phytoplankton and other species during the 1960s and 1970s. 相似文献
960.
改进型经验正交函数海洋声速剖面预报方法 总被引:1,自引:0,他引:1
鉴于深海温跃层以下往往声速值缺乏,声速剖面不完整的原因,提出一种声速剖面的预报方法:在传统经验正交函数预报法基础上,首先改进协方差矩阵的求解方法,将原始数据的空间信息和时间信息有效地融合到协方差矩阵中,通过由大量实测数据统计得出的时间函数的经验公式,得到合成剖面,将二者结合,把不完整剖面垂直向下延拓到海底,较为有效地解决了传统方法求解协方差矩阵和时间函数较粗糙的问题,给出了完整的海洋声速剖面的准确预报.实测数据检验结果表明,改进方法的预报精度比传统方法有了很大提高. 相似文献