Floodplain hydrology of the Mekong Delta,Vietnam     

Nguyen Nghia Hung  José Miguel Delgado  Vo Khac Tri  Le Manh Hung  Bruno Merz  András Bárdossy  Heiko Apel 《水文研究》2012,26(5):674-686

The Mekong Delta is one of the largest and most intensively used estuaries in the world. Each year it witnesses widespread flooding which is both the basis of the livelihood for more than 17 million people but also the major hazard. Therefore, a thorough understanding of the hydrologic and hydraulic features is urgently required for various planning purposes. While the general causes and characteristics of the annual floods are understood, the inundation dynamics in the floodplains in Vietnam which are highly controlled by dikes and other control structures have not been investigated in depth. Especially, quantitative analyses are lacking, mainly due to scarce data about the inundation processes in the floodplains. Therefore, a comprehensive monitoring scheme for channel and floodplain inundation was established in a study area in the Plain of Reeds in the northeastern part of the Vietnamese Delta. This in situ data collection was complemented by a series of high‐resolution inundation maps derived from the TerraSAR‐X satellite for the flood seasons 2008 and 2009. Hence, the inundation dynamics in the channels and floodplains, and the interaction between channels and floodplains, could be quantified for the first time. The study identifies the strong human interference which is governed by flood protection levels, cropping patterns and communal water management. In addition, we examine the tidal influence on the inundation in various parts of the Delta, since it is expected that climate change‐induced sea level rise will increase the tidal contribution to floodplain inundation. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

潮汐对精密单点定位的影响     

肖亮明  蒋胜华 《测绘信息与工程》2010,35(1):19-21

基于IERS2003协议，介绍了地球固体潮，海潮，极潮等改正模型，叙述了各潮汐项改正步骤，分析了各类潮汐改正模型的量级及对精密单点定位的影响。  相似文献   

Characteristics Analysis and Risk Assessment of Extreme Water Levels Based on 60-Year Observation Data in Xiamen,China     

MIAO Qingsheng  YUE Xinyang  YANG Jinkun  WANG Zhifeng  XU Shanshan  YANG Yang  CHU Siqi 《中国海洋大学学报(英文版)》2022,21(2):315-322

Extreme water levels are related to astronomical tides and storm surges.Eleven typhoon systems,which have caused extreme water level rises,were selected based on 60-yr water level data from the Xiamen tide gauge station.In these 11 typhoon systems,the astronomical tide component accounts for 71%-95%of the total water level.The Gumbel distribution of extreme water level rise was estimated,and the impact of typhoon surges on water levels during the return period was analyzed.The ex-treme tide levels caused by typhoons Herb(1996)and Dujuan(2015)are much higher than those of other typhoons and correspond to the return period of 76 yr and 71 yr,respectively.The differences of sea levels in the presence and absence of these two typhoons in the 10-100 yr return period are 5.8-11.1 cm.For the 100-yr return period,the total risks within 10,25,50,and 100 yr increase by 94.3%,85.4%,72.9%,and 54.4%,respectively,if the Herb and Dujuan are not considered.Assuming that typhoon Herb(1996)occurred during the highest astronomical tide,it will produce a water level higher than that of the 1000-yr return period.Sea level rise has an important influence on the water level return period,and the contribution of nonlinear sea level rise in the next 100 yr is estimated to be 10.34%.  相似文献   

南海北部—观测点内潮特征的初步分析   总被引：2，自引：0，他引：2  

邱章  徐锡祯  龙小敏 《热带海洋学报》1996,(4)

采用功率谱分析、调和分析等方法，对南海北部－观测点连续９ｄ（１９８８年５月８—１６日）的温度。盐度和海流及跨越该期间较长的（１９８８年４月２４日－７月２２日）潮位资料进行了分析研究。结果表明，观测点存在着一种内潮现象，其波动的周期在２４ｈ左右，它传播的方向大体是偏北。  相似文献   

黄骅沿海赤潮发生机制的初步探讨          下载免费PDF全文

张启东 《海洋科学》1993,17(6):57-60

报道了黄骅沿海赤潮发生的过程和形成赤潮的生物种类及造成的危害,并对赤潮成因作了初步分析。  相似文献   

大气散射对采用归一化植被指数进行赤潮遥感监测的影响研究   总被引：3，自引：0，他引：3  

唐军武  丁静  王其茂  马超飞 《海洋学报》2004,26(3):136-142

1　引言近年来赤潮灾害在我国海域频繁发生,对沿海环境、经济和人民生产生活都造成一定的影响,因此对赤潮进行实时监测并业务化运行就显得尤其重要.赤潮遥感监测是目前常用手段之一,在实践中取得了一定的效果,但到目前为止还没有一种成熟的算法能用于业务化监测赤潮的发生.很多研究人员借鉴归一化植被指数(NDVI)阈值法、海表温度(SST)异常等来判断赤潮的发生,但归一化植被指数阈值法经常会出现误判或无法区分正常与异常水体的情况.该阈值范围由先验知识得到,没有定量的理论依据.归一化植被指数是陆地遥感中用以表征地表植物覆盖程度和健…  相似文献   

浙江近海夜光藻的分布及其生态学特点   总被引：4，自引：1，他引：4  

陆斗定  张志道 《海洋学研究》1994,12(3):62-69

本文利用历次夜光藻调查资料，阐述了其在浙江近岸海域的分布特点，丰度高峰主要出现在春秋季，夏季亦存在暴发性增殖的可能性，冬季则基本见不到夜光藻的踪迹。杭州湾口等水体浑浊区是夜光藻的低丰度区，仅在春夏季有零星出现，这与水体透明度低、悬浮泥沙含量高及强烈的水动力因子等密切相关。在时间尺度上，夜光藻丰度呈上升趋势，根本原因是海域富营养化加剧的结果。  相似文献   

两层分层流体中初始内孤立波分裂的数值研究     

徐肇廷  贾村  陈旭  文凡 《中国海洋大学学报(自然科学版)》2006,36(3):345-348

本文导得了1个研究内波分裂的射线型二维KdV方程。利用这一方程的一维退化方程进行了实验室尺度下孤立子型内波分裂的数值研究。数值结果表明,深水区的初始内孤立波和实测的内孤立波(内潮)在通过陆坡区时都会产生分裂,并在陆架上(浅水区)生成一内孤立子波列。这表明在实际海洋条件下,深海区内潮的分裂是陆架上海洋内孤立子波包(或波列)生成的主要机制之一。  相似文献   

卡尔曼滤波在GPS潮位数据处理中的应用     

赵力  付晓  刘世萱  张占一 《海洋技术学报》2007,26(4):35-36,71

利用RTK GPS技术测量潮位数据时,在把具体的潮位数据提取出来以后还会存在很多的异常点或不确定点,因此我们要在提取出具体波动的过程中实时的修正,才能得到有效的资料。文中简要介绍了卡尔曼滤波的基本原理,以及如何应用于GPS潮位数据的处理,并通过试验讨论卡尔曼滤波在数据处理中的效果。  相似文献   

Biochemical Mechanism of the Eutrophication and Its Prevention—the Deep Treatment of Waste Water and Its Denitrification and Dephosphorization     

李红山  黎松强 《海洋通报(英文版)》2003,5(1):32-39

Biochemical mechanism of forming the red tide is discussed in this paper.The existence of a large number of nitrates and phosphates in the eutrophic water is the prerequisite of explosive increase of algae and the forming of red tide.Reduction of eutrophication is an important approach to preventing the red tide.The method of deep treatment of the waste water and its denitrification and dephosphorization are introduced,and a new opinion on the red tide formation and fundamental prevention is put forward.  相似文献