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  • Methods for determining the development space in the conservation and utilization planning of uninhabited islands,.

    Ji, Houde; Luo, Meixue; Yang, Shunliang; Sun, Qinqin (2016)
    Marine Science Bulletin
    The conservation and utilization planning of uninhabited islands is an important part of island management system, which is also the link between island administrators and users. How to scientifically and reasonably determine the development space is the core and difficulty in the planning. In this paper, taking the conservation and utilization planning of the Dashan Island and Ding Island as the example, methods of determining the development space for the highly sensitive ecological islands in the premise of ensuring ecological safety space are explored. According to the ecological status of islands, intensity of human disturbance is confirmed as the main assessment factor and assigned based on different space uses, which is used to assess the status of human disturbance. Results suggest the status of island human disturbance is on the slight level and the magnitude is very low, which is consistent with the reality. Also the results show the adaptability of the model. The threshold is used to calculate the development space of the island, which is the slight level of human disturbance in the model. Finally, the applicable scope of this method is discussed.
  • Comparison of spectral partitioning techniques for wind wave and swell.

    Li, Shuiqing; Zhao, Dongliang (2012)
    Marine Science Bulletin
    The ocean waves are generally mixed with wind wave and swell. In order to separate these two kinds of ocean waves, many wave spectral partitioning techniques have been proposed. In this study, a two-dimensional(2D) and three one-dimensional (1D) wave spectral partitioning techniques (denoted as PM, WH, and JP) are examined based on the model simulations and in-situ observations. It is shown that the 2D technique could provide the most reliable results as a whole. Compared with 2D technique, PM and JP techniques obviously overestimate the wind-wave components, and the same situation happens for WH technique at low wind speed. With the adjustment of the partitioning frequency ratio, the 1D PM technique is modified, in which the result agree well with that of the 2D scheme.
  • Changes in magnetic susceptibility and grain size of Holocene sediments of the Pearl River estuary and climate changes reflected by them,

    Cao, Linglong; Wang, Ping; Wang, Jianhua; Wang, Xiaojing; Yang, Jie (2012)
    Marine Science Bulletin
    Through the Pearl River Estuary Wan Qing-sha W2 core AMS 14C dating of sediments, combining with paleomagnetic test, pollen analysis, and comprehensive comparison with other relevant records, the regional framework of Holocene age was established. Using the combined feature grain size and magnetic susceptibility proxies for the environment, climate change information in the area since about 6 000 cal yr BP was obtained. The result showed the area since the middle Holocene had experienced three stages climate changes of warm and dry - cool and wet temperature and humidity. South area of China in the late Holocene climate (especially rainfall) had important changes, corresponding to the Northern Hemisphere solar radiation reducing, air temperature decreasing, Asian monsoon weakening, and it had close ties with activities to strengthen El Nino - Southern Oscillation events.
  • An approach to estimate tidal dissipation with single-point high-frequency ground wave radar data <OT>=单点高频地波雷达资料估算潮能耗散的方法.

    Mao, Huabin; Chen, Ju; Qiu, Chunhua; Lian, Shumin (2012)
    Marine Science Bulletin
    Using the single-point ground wave (GW) radar data at Shensi Station and the water level data at three stations (Shengsi, Luchaogang and Daishan), the authors obtained the flow vectors from the radial velocity of GW radar observation, and calculate four sub-tidal harmonic constants (O1, K1, M2 and S2). The tidal characteristics derived from the GW radar dataset agreed well with those from the tidal gauge data. The authors also analyzed the tidal energy flux and tidal energy dissipation rate. There was a good relationship between the tidal energy dissipation rate and topography. The study showed a good way to calculate tidal energy dissipation rate using GW radar data.
  • Analysis of tidal and residual currents across semi-enclosed bay mouth based on shipboard ADCP measurements.

    Li, Xibin; Sun, Xiaoyan; Yao, Zhigang (2012)
    Marine Science Bulletin
    Based on 25 hours shipboard ADCP measurements across semi-enclosed bay mouth(Kemen Channel), time series of tidal currents over 12 sites, which distribute evenly along the transect, were constructed to improve our understanding of tidal characteristics and residuals in this region. The tidal currents in Kemen Channel were identified as the regular semidiurnal and reversing tidal flows, with its behaviour more like standing waves. Moreover, the flood currents in the lower layers were found to be ahead of that in the upper layers and vice versa for ebb tides. The major of tidal ellipse for M2 constituent was found to be larger close to the southern side of the channel, with its incline also increasing toward the south. The signs of M4 constituent were also found mainly nearby the end points of this transect, indicating the importance of nonlinearity in tidal dynamics due to the shallower topography. A two-layer structure was found for the residual currents in Kemen Channel, flowing northeastwardly out of the Bay in upper 20 m and southwestwardly into the bay in the lowers. Besides approximate 4.81x108 m3 water exchanges were determined between the Luoyuan Bay and outer seas by the calculation of tidal flux through Kemen Channel.
  • Internal tides in the northern South China Sea from 20-day in-situ mooring observations in 1998

    Cai, Yang; Guo, Pu; Fang, Wendong (2012)
    Marine Science Bulletin
    20-day in-situ ADCP current and CTD data are used to investigate the characteristics and energy of the internal tides in the northern South China Sea (NSCS). The results show that the O1, K1, M2 and S2 constituents of internal tides are energetic and diurnal constituents (O1 and K1) are dominating. In the observational period, the current vectors of these four constituents all rotate clockwise and the maximum semi-major axe of internal tidal ellipses is more than 14 cm/s. The variation of ocean temperature shows that the internal tides present obvious quasi-diurnal oscillation and the average amplitude reaches 50 m. Furthermore, these internal tides carry high energy and appear to be intermittent. The maximum values of KE (PE) during the observational period are up to 2 (3.5) kJ/m2 for diurnal internal tides, and up to 1 (1.5) kJ/m2 for semidiurnal internal tides.
  • Correction of seabed layer thickness in processing subbottom profile data.

    Wang, Fangqi; Hu, Guanghai; Dong, Lifeng; Tao, Changfei (2012)
    Marine Science Bulletin
    The subbottom profiling is an important means of marine engineering survey, hazardous geology study and continental shelf scientific research. The accuracy of subbottom profile data interpretation has a direct impact on the research and investigation results. Because some of profilers’ transducer and hydrophone are separately installed, when the survey area is very shallow, distortion of shallow layers will be caused if it is seen as a self-excited and self-collected single-channel seismic system. According to the principle of subbottom profiler, the distortion correction formula is deduced and analyzed, providing actual value to using C-View software to interpret such subbottom profile data more accurately. In addition, the seabed sediments sound velocity is one of the key parameters when acquiring and processing the subbottom profile data. On the basis of comparing some sound velocity forecasting empirical equations, the LU Bo’s equation was considered the most appropriate to predict the seabed sediments, sound velocity at near-shore of China. In a survey of an artificial island site, the LU Bo’s equation and the porosity data obtained from geological drilling were utilized to predict the sediments sound velocity, and the sound velocity structure profile was plotted, which was applied in processing the subbottom profile data of the artificial island investigation. The method of using porosity data to predict sediments sound velocity in processing subbottom profile data can improve the interpretation accuracy and it’s of practical significance.
  • Distribution of clay minerals in surface sediments off Yangtze River estuary.

    Lan, Xianhong; Zhang, Zhixun; Li, Rihui; Wang, Zhongbo; Chen, Xiaohui; Tian, Zhenxing (2012)
    Marine Science Bulletin
    Based on the clay minerals, content analysis from 187 stations in the surface sediments, this paper dealt with the assemblages and the distributions of clay minerals in the surface sediments off the Yangtze River estuary. The research results showed that the illite dominates the surface sediments off the Yangtze River estuary with the smectite or kaolinite the second rank and chlorite the third rank; the illite-smectite- kaolinite- chlorite-assemblage is the main type of the clay minerals assemblage in the area, with the illite-kaolinite-chlorite-smectite -type as the second rank; the source of clay mineral is mainly from the Yellow River and the Yangtze River. The Q-type cluster analysis show that sediments from both recent and ancient Yellow River were deposited mainly in the northeast part of the study area to the north of 29°30′. Substance from the Yangtze River was deposited mainly in the western and middle parts off the Yangtze River estuary.
  • Preliminary analysis on the interdecadal variation characteristics of typhoon over the Northwestern Pacific in the past sixty years.

    Yu, Fan; Zhang, Tao; Li, Pei; Li, Xiangjun (2012)
    Marine Science Bulletin
    Using typhoon data over the Northwestern Pacific (NWP) in 60 years (1950-2009), the interdecadal variations of typhoon frequency, track and intensity are statistically analyzed. The results showed that the frequency of typhoon over the NWP was high in 1960s and low in 1970s. From the late 1990s, the frequency is low again. The track of typhoon was mainly shifting, and the average track was at the southern NWP in 1960s and 1970s, but in recent 10 years, the track was at the northern NWP. The intensity of typhoon was strong in 1950s and 1960s, but becomes weak in recent 25 years. In high frequency periods of typhoon, the subtropical high of NWP was weak and its position appears easternly. The distribution of Sea Surface Temperature (SST) shows characteristics of “La Nina” event. In low frequency periods of typhoon, the subtropical high of NWP is strong and its position appears westernly. The distribution of SST shows characteristics of “El Nino” event.
  • Study of the water quality in Liaohe Park based on the model of GAM.

    Song, Wenping; Dai, Yuanyuan; Dong, Yubo (2012)
    Marine Science Bulletin
    This paper assesses the quality of Daliao river through Liaohe Park based on the model of GAM for water quality analysis and the monitoring data from 2006 to 2011.The results showed that the value of pH per year tended to the average; the DO in 2011 was much higher than that in other years, and the DO in 2006 was lower than the standard value; the quality risk in six sections was still higher than the standard value in 2007, which was caused by the high concentrations of COD. However, the value of ammonia nitrogen changes was only 40% related to DO and COD.
  • Discussion on storm-induced liquefaction of the superficial stratum in the Yellow River subaqueous delta.

    Xu, Guohui; Sun, Yongfu; Yu, Yueqian; Lin, Lin; Hu, Guanghai; Zhao, Qingpeng; Guo, Xiujun (2012)
    Marine Science Bulletin
    Geological disasters on the superficial seafloor were revealed in geological investigation on the Yellow River subaqueous delta. Combined with dynamic triaxial tests and wave flume experiments, occurring conditions and forming patterns of liquefaction as well as motion of the liquefied soil were explained in this paper. Based on the viewpoint that the geological disasters were formed due to silty soil liquefaction under storm waves, re-stratification issue of the superficial stratum was analyzed. Movement of the liquefied soil agreed with the wave, leading to differentiation of the soil particles. Research issues in respect of geological, environment and engineering of storm-induced liquefaction were also discussed.
  • Distribution characteristic and variation trend of planktonic dinoflagellate in the Taiwan Strait from 2006 to 2007.

    Lin, Gengming; Yang, Qingliang; Lin, Weihan; Wang, Yu (2012)
    Based on 4 cruise surveys from July 2006 to October 2007 in the Taiwan Strait, the species composition, community structure and spatio-temporal distribution of dinoflagellate were studied. A total of 131 dinoflagellates belonging to 18 genera were identified. The population was dominated by hyperthermal and hyperhaline species accounting for 72.52% of the total species. Eurythermal and euryhaline species were the second most common one accounting for 25.19% of the total species. It was only 2.29% for neritic species. The maximum species number occurred in summer, while the maximum cell density appeared in spring. The average dinoflagellate cell density was 404.96×104 cells/m3. It showed that the dinoflagellate cell density increased from the nearshore waters to the open sea and from the north to the south. Compared with the results during 1984-1985, the horizontal distribution pattern and seasonal variation of the dinoflagellate have not changed significantly, but the dinoflagellate cell density increased by 3.01 times. Further analysis of the dinoflagellate abundance variations both in the spatial and temporal aspects, indicated that the abundance of dinoflagellate increased more significantly in cold seasons, and there was a larger increase in the north of the Taiwan Strait. Besides,the dinoflagellate community structure changed notably. It showed that the diversity and evenness index were relatively high, and the proportion of dinoflagellate cell density to the total phytoplankton increased.
  • A non-parametric indicator Kriging method for generating coastal sediment type map.

    Liu, Fucheng; Peng, Jun; Zhang, Cunyong (2012)
    Marine Science Bulletin
    Coastal sediment type map has been widely used in marine economic and engineering activities, but the traditional mapping methods had some limitations due to their intrinsic assumption or subjectivity. In this paper, a non-parametric indicator Kriging method has been proposed for generating coastal sediment map. The method can effectively avoid mapping subjectivity, has no special requirements for the sample data to meet second-order stationary or normal distribution, and can also provide useful information on the quantitative evaluation of mapping uncertainty. The application of the method in the southern sea area of Lianyungang showed that much more convincing mapping results could be obtained compared with the traditional methods such as IDW, Kriging and Voronoi diagram under the same condition, so the proposed method was applicable with great utilization value.
  • Establishment and data analysis of sea-state monitoring system along Taiwan coast.

    Feng, Xiangbo; Wang, Hao; Yan, Yixin (2012)
    Marine Science Bulletin
    Taiwan Island is at the joint of Eurasian Continent and Pacific Plate, under threatening of typhoons and northeasterly strong winds. Consequently, enormous human lives and properties are lost every year. It is necessary to develop a coastal sea-state monitoring system. This paper introduces the coastal sea-state monitoring system (CSMS) along Taiwan coast. The COMC (Coastal Ocean Monitoring Center in National Cheng Kung University) built the Taiwan coastal sea-state monitoring system, which is modern and self-sufficient, consisting of data buoy, pile station, tide station, coastal weather station, and radar monitoring station. To assure the data quality, Data Quality Check Procedure (DQCP) and Standard Operation Procedure (SOP) were developed by the COMC. In further data analysis and data implementation of the observation, this paper also introduces some new methods that make the data with much more promising uses. These methods include empirical mode decomposition (EMD) used for the analysis of storm surge water level, wavelet transform used for the analysis of wave characteristics from nearshore X-band radar images, and data assimilation technique applied in wave nowcast operation. The coastal sea-state monitoring system has a great potential in providing ocean information to serve the society.
  • Climate warming and sea level rise.

    Yue, Jun; Dong, Yue; Wu, Sangyun; Geng, Xiushan; Zhao, Changrong (2012)
    Marine Science Bulletin
    Based on a large number of actual data, the author believe that the modern global warming and sea level rise resulted from climate warming after the cold front of the Little Ice Age about 200 years ago and the developmnet of the sea level rise phase. In the past 30 years, the rate of sea level rise was increasing, which is under the background of the average temperature uplift 0.2F°(0.11 °C)every 10 years in succession from the 1980s to the past 10 years this century. On the basis of the absolute and relative sea-level rise rate that was calculated from the tidal data during the same period at home and abroad in the last 30 years, in accordance with the resolutions of the 2010 climate conference in Cancun, at the same time, considering the previous prediction and research, the world’s sea levels and the relative sea level in Tianjin, Shanghai, Dongying, Xiamen, Haikou and other coastal cities that have severe land subsidence in 2050 and 2100 are calculated and evaluated.
  • Analysis on the time variation and cycle of observed Argo profile data.

    Zhang, Shengmao; Wu, Yumei; Yang, Shenglong (2012)
    Marine Science Bulletin
    The remote sensing data which are used by marine fishery forecast only can get the information of ocean surface, while Argo data can provide fishery forecast with temperature and saltinity data of deeper area. To use Argo data in cycle, we need to compute its circle to improve the quality of forecast. In 2001- 2008 , the longer circle was 62.7 days and 117.5 days , and the shorter circle was 4.9 days and 9.8 days, which were obtained by power spectrum estimation. And there was an unobvious circle of 7 days. There existed big changes in observed profile data amount between years and within a year.
  • Modeling of ocean mesoscale eddy and its application in the underwater acoustic propagation.

    Li, Jiaxun; Zhang, Ren; Liu, Chenzhao; Fan, Hongjun (2012)
    Marine Science Bulletin
    Aiming at the influence of ocean mesoscale eddy on underwater acoustic propagation, a theoretical computation model of ocean mesoscale eddy was established based on the in-situ hydrographic data in the sea area of ocean mesoscale eddy. An underwater acoustic model-MMPE was used to simulate the acoustic propagation under the influence of different types, different intensities and positions of eddies, and different frequencies and depths of sources. It is found that warm-core eddy can make the convergence zone "move back" and the width of it increases, while cold-core eddy can make the convergence zone "move forward" and the width of it decreases. The bigger the intensity of eddy, the more notable the "forward "or "back "effect. Sound source located depths and source frequencies can change the acoustic propagation characteristics in the eddy area.
  • Distribution of heavy metals in suspension in Bohai Bay

    Dong, Yubo (2016)
    Marine Science Bulletin
    Selecting suspension sample 51 stations in Bohai Bay contents of heavy metals(Fe, Mn, Si, Ba) analysis, studied the distribution of the suspension of heavy metals. It Showed that in the study area, the content of iron was the highest, silicon content was lowest; in descending order: Fe>Mn>Ba>Si; the coefficient of variation is between 7.60 and 110.35; except barium greater the degree of dispersion (coefficient of variation is greater than 100).With the samples of stations, the 4 kinds of heavy metals are from low to high, from the south to the north. Silicon content was the highest in 51 stations. The other 3 elements appeared in 50 stations.
  • Effects of salinities on the growth and nutrient composition in the muscle of Exopalaemon carinicauda

    Jiang, Jufeng; Wu, Huimin; Guo, Huayang; Zhang, Zhenguo; Liu, Xiaolian; Xia, Sudong; Zhuang, Baolu; Fu, Zhiru (2016)
    Marine Science Bulletin
    The effect of salinity on the growth and muscle nutritional quality of the Exopalaemon carinicauda was studied through testing the survival rate, specific growth rate, muscle nutrient composition, amino acid composition and content by the culturing in different salinities(0-30).The results showed that the survival rate of salinity (0-30) had no significant difference (P>0.05), and the specific growth rates at salinity 15 and salinity 20 were significantly higher than others(P>0.05); the muscle moisture content and the crude fat content significantly decreased(P<0.05), while the muscle crude protein content significantly increased with an increase in the environment salinity from 0 to 30(P <0.05).The crude ash content with salinity increase had a slight increase; the muscle crude protein content (18.2) at salinity 15 was significantly higher than that at salinity 0,5, or 10(P <0.05), but there was no significant difference between salinity 15 and salinity 20(P>0.05). No significant difference was found in total amino acid content or total essential amino acid content from salinity 0 to 30(P>0.05). Total delicious amino acid content at salinity 15-30 was significantly higher than those at salinity 0-10 (P<0.05), while there was no significant difference from salinity 15 to 30(P>0.05). The results suggest that the suitable salinity for muscle nutritive value ranges from 15 to 30, and the Exopalaemon carinicauda can potentially be cultured above the salinity 15.
  • A preliminary study on food consumption, preference and day-night predatory difference of Asterias amurensis on Scapharca broughtonii

    Zhang, Tianwen; Liu, Guangbin; Liu, Enfu; Zheng, Yongyun; Qiu, Zhaoxing (2016)
    Marine Science Bulletin
    In order to study the food consumption, preference and day-night predatory difference of Asterias amurensis on Scapharca broughtonii, the experiments were carried out at the temperatures ranging from 16 ℃ to 20 ℃, salinity of 28.2 ± 2.1, dissolved oxygen of 7.5±0.7 mg/L and pH of 8.0 ± 0.3.The results provided basic data for promoting steady and healthy development of the multiplication and cultivation of S. broughtonii. The results of food consumption suggested that the food intake of starfish increased with the density of S. broughtonii at all conditions. The food consumption of starfish in different sizes on S. broughtonii in the same size had no significant difference (p>0.05), but it was significantly different among S. broughtonii in different sizes. The starfish had the highest feeding rate on the smallest S. broughtonii. Our findings also verified the positive relation between the weight of food intake of starfish in different sizes on the density and size of S. broughtonii. The feeding rhythm of starfish on S. broughtonii in different sizes showed a certain day-night difference, higher at night than in the day. The maximum food consumption occurred when the size of S. broughtonii became larger. The results showed that 30 ind/m2 was the suitable sea bottom sowing density for S. broughtonii. Our data indicated that the ability to avoid predators and rivals increased as the shell length rose. Based on prey selectivity, bivalves that have a lower commercial value may be used to clear away A. amurensis.

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