南海北部琼东南盆地中央峡谷成因新认识   总被引：3，自引：0，他引：3  

王亚辉  张道军  赵鹏肖  陈扬  黄灿  苏榆丰 《海洋学报》2016,38(11):97-104

通过对区域构造断裂体系和逐渐连片的高分辨率三维地震资料的精细解析,认识到琼东南盆地中央峡谷的形成机制除了与晚中新世区域构造变动、大规模海平面下降、充足物源供给以及凹槽型古地形特征等因素相关之外,还存在另外一个非常重要因素:峡谷底部早期隐伏断裂带的存在。研究表明:琼东南盆地中央坳陷带发育平行于陆架坡折的大规模深水峡谷,峡谷底部发育大型走滑断层以及走滑断层派生出一系列次级断层形成的地层破碎带,认识到峡谷的形成、规模以及展布方向均受断裂带影响;相应地峡谷的充填及演化亦是受物源、海平面变化、重力流作用等多种因素共同作用和相互叠加的过程。从而为研究经历了裂陷期和坳陷期盆地演化过程形成的大型峡谷提供了科学依据。  相似文献   

珠江口海域主导光学因子的遥感分类及其变化特征     

姜广甲  段国钦  黄志雄  蔡伟叙  卢楚谦  苏文  阳杰  张纯超 《海洋学报》2016,38(9):64-75

基于2014年5月和8月珠江口海域的现场和实验测量数据,分析了光学因子和生态参数的动态变化特征,并找出该海域的主导光学因子;基于模拟的MODIS数据,构建了水体组分特征波长处吸收系数的遥感反演模型,并结合MODIS卫星遥感影像,依据IOCCG规则对主导光学因子进行遥感分类,揭示了珠江口海域2014年逐月水体主导光学因子的动态变化特征。结果表明,珠江口海域水体以a_d、a_g以及两种共同主导类型为主,并且a_g、a_d两种光学因子主导类型所占比例最大,其次是a_g主导类型,a_d主导类型所占比例最小。同时发现a_d（442）、a_dg（442）均与无机悬浮物浓度有较好的正相关关系,说明CDOM和悬浮泥沙具有相似的来源和动力变化过程。  相似文献   

Spatiotemporal distributions of influential tropical cyclones and associated economic losses in China in 1984–2015     

Yanjun Wang  Shanshan Wen  Xiucang Li  Fischer Thomas  Buda Su  Run Wang  Tong Jiang 《Natural Hazards》2016,84(3):2009-2030

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Long-term effects of di-octyl phthalate on the expression of immune-related genes in <Emphasis Type="Italic">Tegillarca granosa</Emphasis>     

王稷  李晔  戴娟  苏秀榕  李成华  沈灵灵 《中国海洋湖沼学报》2016,34(3):423-429

Di-octyl phthalate (DOP) is widely used as a plasticizer in the plastics industry. As a result, DOP is often found in marine water ecosystems where many species are exposed to it. Our objective was to evaluate the effect of long-term (14 d) DOP exposure (2.6, 7.8, or 31.2 mg/L) on the expression of immunerelated genes in Tegillarca granosa. The expression of small heat shock protein (sHSPs) and tissue inhibitor of metalloproteinase (TIMP) were highest in clams exposed to 31.2 mg/L DOP on days 7 and 14. The relative expression of Tg-ferritin, superoxide dismutase (SOD), and metallothionein (MT) increased initially then decreased as the concentration of DOP increased. The hemoglobin of T. granosa (Tg-HbI) exhibited two distinct expression patterns at two time points. Our results suggest that the immune response of T. granosa against DOP pollution varies depending on the dose. Additionally, we identified some immune-related genes that are promising candidates for biomarkers of DOP.  相似文献   

基于大气电场资料的雷电临近预警研究     

秦微  张其林  姜苏  陈媛  苏建峰 《南京气象学院学报》2016,8(3):247-251

通过分析深圳地区2012年6—9月17次雷暴过程的电场观测资料,并结合广东省闪电定位资料,发现当雷暴云移近电场仪测站时,在测站的防护区内(距测站10 km半径范围内),闪电发生前的电场幅值快速增加且伴随有快变抖动的现象,并且快变抖动和闪电的发生具有0-1化对应关系,即当有电场的快变抖动出现的情况下,电场达到一定阈值并维持一段时间后,防护区内发生闪电的可能性很大.因此根据大气电场的波形特征,提取出与闪电相关性较高的因子,利用多元回归技术建立一套预报方程,根据该预报方程得出最佳预警参数.结果表明:当大气电场阈值达到0.86 kV/m,且在10.73 min内电场能维持在阈值上,并伴随有电场的抖动时,在防护区内发生闪电的可能性很大,预警准确率达53%.  相似文献   

质量守恒的订正算法在GRAPES_GFS中的应用   总被引：1，自引：0，他引：1       下载免费PDF全文

苏勇  沈学顺  张倩 《应用气象学报》2016,27(6):666-675

如何在长时间积分的过程中保证模式大气的质量守恒是数值模式动力框架面临的基本问题之一,对于半拉格朗日动力框架来说, 在理论上要满足质量守恒面临着诸多的困难,质量订正方案不失为一种简单可行的选择。中国气象局数值预报中心的GRAPES_GFS (Global-Regional Assimilation and PrEdiction System, Global Forecast System) 在长时间积分过程中质量损失问题较为明显,该研究工作借鉴C-CAM (Climate-Community Atmosphere Model) 中对地面气压进行订正控制模式质量守恒的思路,在GRAPES_GFS中开发了一种对每个网格内的质量按照不同权重系数进行调整、控制模式大气总质量守恒的算法。经过一系列的试验,验证了该方法在GRAPES_GFS中的可行性,在保证模式质量守恒的情况下可有效减小高度场的预报偏差,缓解模式预报结果中天气系统偏弱的问题,在实际业务预报中有一定应用价值。  相似文献   

Comparing the spatial extent of Atlantic basin tropical cyclone wind and rain fields prior to land interaction     

Qiao Guo 《自然地理学》2016,37(1):5-25

Understanding changes in the size of tropical cyclone (TC) wind and rain fields before landfall can improve identification of areas that may experience damage. We examine 25 Atlantic basin TCs for 36 h before gale-force winds (R17) cross land. Rain field extents are measured from satellite estimates of rain rates using a Geographic Information System. In each quadrant, R17 is obtained from the Extended Best Track data-set and correlated with the extent of the rain field. In general, both fields expand prior to landfall. The non-linearity of this trend poses problems for persistence forecast models. The largest wind fields are located over the Atlantic Ocean. Correlations between wind and rain field extent are strongly positive for Atlantic cases regardless of whether extratropical transition (ET) occurs and are associated with the direction of vertical wind shear. Poor correlations exist for Gulf observations. Rain fields extend farther towards the east during ET when vertical wind shear is stronger, but wind fields are not significantly different when separating cases based on whether or not ET occurs. As rain fields extend farther than wind fields in 33% of Gulf cases, moderately heavy rainfall may commence before damaging winds arrive, decreasing the time available for preparedness activities.  相似文献   

中国海洋渔业资源可持续利用的动态评价与空间分异   总被引：1，自引：1，他引：0  

孙康  周晓静  苏子晓  张华 《地理科学》2016,36(8):1172-1179

运用基于多智能体遗传算法的投影寻踪模型和核密度估计模型,对2003~2012年中国沿海11个省市（不含港澳台）海洋渔业资源可持续利用水平的时空格局演化进行测度。研究结果表明：从投影方向上看,捕捞技术、捕捞强度和渔业产业结构等,逐渐上升为影响海洋渔业资源可持续利用水平的重要因子;从时空格局上看,上海的海洋渔业资源可持续利用属于高水平区板块,天津、河北、江苏、浙江和广西属于中等水平区板块,辽宁、山东、福建、广东和海南属于低水平区板块;从总体上看,海洋渔业资源可持续利用呈现不可持续性,具体表现为时间演化可持续,空间演化不可持续,时空演化呈现出不可持续的两极分化趋势。未来高水平区板块应保持原来的发展模式,中等水平区板块的可持续利用路径选择是保中争高,低等水平区板块的可持续利用路径选择是追中攀高。  相似文献   

红树植物中铝的示波极谱滴定     

杨孙楷  苏循荣 《台湾海峡》1992,11(4):359-362

锌在示波极谱图上具有敏锐的切口,在pH为2～3的HCl-NaCl介质中,可用EDTA直接滴定铝。当滴加EDTA至切口消失时,即达到滴定终点。对红树植物体中铝的分析结果表明:此方法具有直观、操作简便、分析快速的优点,回收率相对误差在10%左右。几种红树体的不同部分铝的质量分数(干重计)分别是:叶为(6.69～29.9)×10~(-3),树干为(1.91～26.8)×10~(-3),常年生树枝为(5.54～29.8)×10~(-3).  相似文献   

Simulation of the seasonal thermal structure in the Bohai Sea   总被引：1，自引：0，他引：1  

Huang Daji  Su Jilan  Chen Zongyong 《海洋学报(英文版)》1995,14(4):461-474

The seasonal thermal structure in the Bohai Sea are examined with a three-dimensional boroclinic primitive equation model for shelf sea.The evolution of the seasonal thermal stratification is well simulated.The stratification appears early in April,first in the area off Qinhuangdao and it is well developed in the middle of May.It intensifies with synoptic and neap-spring fluctuations throughout the summer and reaches its maximum in the middle of July.Eventually,it is destroyed at the end of September.There are cold water belts between well-mixed and stratified regions.They are loGated on the mixed side of tidal fronts,and coincide with the isolines for a temperature difference of 1-2℃ between surface and bottom.The sea surface temperature (SST) distribution shows local maxima at the head of three bays and to the south of Qinhuangdao during the summer.The Bohai Sea responds to the variability in the atmospheric forcing and in tides with the synoptic and neap-spring variations of SST,as well as in the stratification and in variable positions of tidal fronts.  相似文献