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961.
以Hela细胞为研究对象,通过四氮唑蓝(MTT)比色法、光学显微镜观察、Giemsa染色以及DNA凝胶电泳,研究了几种产YTXs的赤潮藻种多边舌甲藻(Lingulodinium polyedrum)CCMP1931,具刺膝沟藻(Gonyaulax spinifera)CCMP409,网状原角藻(Protoceratium reticulatum)CCMP2776粗提液对细胞的凋亡诱导作用,并通过LC-MS/MS分析各粗提液的成分及毒性大小。结果表明:CCMP1931、CCMP409、CCMP2776均对Hela细胞有毒性作用,能引起细胞凋亡事件,同时,分析其毒素成分发现,3种藻均能产生YTX及其衍生物,且相对毒力大小为CCMP2776CCMP1931CC-MP409。  相似文献   
962.
根据鸭绿江西水道口外两个站位大小潮实测悬沙数据,结合表层沉积物特征及潮流动力分析结果,从悬沙浓度、悬沙输沙量和悬沙粒级3个方面,分析了悬浮泥沙浓度大小潮时空变化特征及其与潮汐、潮流动力因素的关系,净输沙量特征及输沙方向、悬沙各粒级百分含量与涨落潮及泥沙沉积物之间的关系等内容。计算分析表明:影响悬沙动力特征的主要因素为空间位置、动力强弱及泥沙源;1#站位细粒沉积物丰富,潮流及输沙受口门地形控制,2#站位地形平坦,沉积物颗粒粗,泥沙源来自异地;悬沙浓度受潮流、潮汐动力影响呈规律性变化,输沙量受潮流动力、泥沙来源双重影响;两个站位悬沙粒级百分含量随涨落潮的峰值变化及与流速、流向、潮位的对应关系的不同,有效的指示了沉积物空间分布特征,反映了外部环境对悬沙的作用过程。  相似文献   
963.
海洋特别保护区是海洋保护区的类型之一,海洋特别保护区是指在我国管辖海域以海洋资源可持续利用为宗旨,对海洋资源密度高、产业部门多、开发强度大,生态敏感和脆弱的海域,依法划定出一定范围的海域予以特殊保护管理,以确保科学、合理,安全、持续地利用各种海洋资源,达到最大的社会经济效益。文章对山东省海洋特别保护区的现状、问题进行分析并提出相应的发展对策建议。  相似文献   
964.
黄海冷水团的化学水文学特征   总被引:2,自引:1,他引:1  
Based on the field data obtained during summer cruises in 2006, the overall perspective of chemical and hydrographic characteristics of the Yellow Sea Cold Water Mass(YSCWM) are discussed through the crossYSCWM transect profiles and horizontal distributions of hydrological and chemical variables, with emphasis on the differences between the northern Yellow Sea Cold Water Mass(NYSCWM) and the southern Yellow Sea Cold Water Mass(SYSCWM). The results show that YSCWM is characterized by low temperature(10°C) and dissolved oxygen(DO) concentration, high salinity(32.0) and nutrient concentrations. Compared to the SYSCWM, the NYSCWM possesses lower values of temperature, salinity and nutrient concentrations but higher values of DO.Also its smaller variation ranges of variables(except for temperature) demonstrate that NYSCWM is more uniform than that of SYSCWM. In addition, thermocline is more intensive in the SYSCWM than that of NYSCWM.Furthermore, DO and Chl a maxima appear at the depth of 30 m in the SYSCWM, while these phenomena are not obvious in the NYSCWM.  相似文献   
965.
一定厚度的油膜对海浪的抑制模型研究   总被引:1,自引:0,他引:1  
本文结合海浪谱的作用量平衡方程,给出了一定厚度油膜对海浪的抑制模型,该模型不仅与油膜的物理参数有关,而且与环境参数有关。文中开展了抑制比对这些参数的敏感性分析,数值模拟结果表明:动力学粘性,表面/界面弹性、油膜厚度、油膜覆盖率等参数对抑制比的影响较大,但油膜的其他物理学参数如:密度、表面/界面张力,表面/界面粘度几乎对抑制比不产生影响;而且,文中还发现风速和风向对抑制比的影响较大。一般情况下,油膜对雷达回波信号的抑制,只需考虑油膜对海浪的抑制作用;但对厚乳化溢油而言,还应考虑到介电常数的减小对雷达回波信号的抑制。将本文建立的抑制比模型所得结果与墨西哥湾溢油事故期间的15景ENVISAR ASAR影像所得抑制比结果进行了比较。  相似文献   
966.
The Fukushima nuclear accident in 2011 released large amounts of radionuclides, including ~(137)Cs, into the Pacific Ocean. A quasi-global ocean radioactive transport model with horizontal grid spacing of 0.5°×0.5° and 21 vertical layers was thereafter established to study the long-term transport of the Fukushima-derived ~(137)Cs in the ocean.The simulation shows that the plume of ~(137)Cs would be rapidly transported eastward alongside the Kuroshio Current and its extensions. Contaminated waters with concentrations lower than 2 Bq/m3 would reach the west coast of North America 4 or 5 years after the accident. The ~(137)Cs tends to be carried, despite its very low concentration, into the Indian and South Pacific Oceans by 2016 via various branches of ocean currents.Meanwhile, the ~(137)Cs concentrations in the western part of the North Pacific Ocean decrease rapidly with time. Up to now the highly contaminated waters have remained in the upper 400 m, showing no evidence of significant penetration to deeper layers.  相似文献   
967.
气候模式FIO-ESM对2015/16年厄尔尼诺的预测   总被引:1,自引:0,他引:1  
Recently atmospheric and oceanic observations indicate the tropical Pacific is at the El Ni?o condition. However,it's not clear whether this El Ni?o event of this year is comparable to the very strong one of 1997/98 which brought huge influence on the whole world. In this study, based on the Ensemble Adjusted Kalman Filter(EAKF)assimilation scheme and First Institute of Oceanography-Earth System Model(FIO-ESM), the assimilation system is setup, which can provide reasonable initial conditions for prediction. And the hindcast results suggest the skill of El Ni?o-Southern Oscillation(ENSO) prediction is comparable to other dynamical coupled models. Then the prediction for 2015/16 El Ni?o by using FIO-ESM is started from 1 November 2015. The ensemble results indicate that the 2015/16 El Ni?o will continue to be strong. By the end of 2015, the strongest strength is very like more than 2.0°C and the ensemble mean strength is 2.34°C, which indicates 2015/16 El Ni?o event will be very strong but slightly less than that of 1997/98 El Ni?o event(2.40°C) calculated relative a climatology based on the years1992–2014. The prediction results also suggest 2015/16 El Ni?o event will be a transition to ENSO-neutral level in the early spring(FMA) 2016, and then may transfer to La Ni?a in summer 2016.  相似文献   
968.
Generation, morphology, and distribution of authigenic minerals directly reflect sedimentary environment and material sources. Surface sediments were collected from the western Gulf of Thailand during 2011–2012, and 159 samples were analyzed to determine detrital minerals. Authigenic minerals, including siderite, pyrite, and glauconite, are abundant whereas secondary minerals, such as chlorite and limonite, are distributed widely in the study area. Siderite has a maximum content of 19.98 g/kg and appears in three types from nearshore to continental shelf, showing the process of forming-maturity-oxidation. In this process, the Mn O content in siderite decreases, but Fe_2O_3 and Mg O content increase. Colorless or transparent siderite pellets are fresh grains generated within a short time and widely distributed throughout the region; high content appears in coastal area where river inputs are discharged. Translucent cemented double pellets appearing light yellow to red are mature grains; high content is observed in the central shelf. Red-brown opaque granular pellets are oxidized grains,which are concentrated in the eastern gulf. Pyrite is mostly distributed in the central continental shelf with an approximately north–south strip. Pyrite are mainly observed in foraminifera shell and distributed in clayey silt sediments, which is similar to that in the Yangtze River mouth and the Yellow Sea. The pyrite in the gulf is deduced from genetic types associated with sulfate reduction and organic matter decomposition. Majority of glauconite are granular with few laminar. Glauconite is concentrated in the northern and southern parts within the boundary of 9.5° to 10.5°N and is affected by river input diffusion. The distribution of glauconite is closely correlated with that of chlorite and plagioclase, indicating that glauconite is possibly derived from altered products of chlorite and plagioclase. The K_2O content of glauconite is low or absent, indicating its short formation time.  相似文献   
969.
1973 年以来射阳河口附近海岸蚀淤变化遥感分析   总被引:1,自引:0,他引:1  
闫秋双  刘荣杰  马毅 《海洋科学》2015,39(9):94-100
以射阳河口北部扁担港口和射阳河口南部斗龙港口之间的海岸作为研究区,基于1973,1987,2000和2013年四期Landsat影像提取了该岸段岸线,并进行了时空变化分析。结果表明,射阳河口以北的扁担港口—射阳河口岸段仍处于侵蚀状态,呈现侵蚀—淤积—缓慢侵蚀的变化格局,40 a间侵蚀面积为12.6 km2,淤积面积为1.0 km2;射阳河口以南的射阳河口—斗龙港口岸段处于淤积的态势,呈现淤积—快速淤积—缓慢淤积的格局,40 a间淤积的面积为223.1 km2,仅在2000~2013年间该岸段北部出现了侵蚀。结论是虽然射阳河口以南岸段仍总体处于淤积的过程中,但是近年来江苏海岸的侵蚀范围已经扩展到了射阳河口以南,这证明了江苏海岸侵蚀岸段有进一步扩大的趋势。  相似文献   
970.
利用多代卫星测高数据计算中国近海及邻域重力异常   总被引:1,自引:0,他引:1  
为提高海洋重力场数据的精度和空间分辨率,联合Jason-1/2、T/P、Envisat、ERS-1/2、Geosat等多代卫星测高数据计算中国近海及邻域(0°~42°N,100°~140°E)2′×2′重力异常。对卫星测高数据分别进行共线处理和自交叉点平差,并以T/P卫星测高数据为基准进行多星数据联合平差,有效削弱了卫星测高数据的时变影响和不协调性;利用逆Vening-Meinesz公式计算重力异常,与船测重力相比,均方根误差为5.4 mgal。结果表明,通过引入高精度的卫星测高数据,结合多项平差处理手段,提高了海洋重力异常的计算精度。  相似文献   
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