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近15年来长江口控制站徐六泾悬沙变化特征研究
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作者 刘帅 何青 +2 位作者 谢卫明 郭磊城 沈芳 《长江流域资源与环境》 CAS CSSCI CSCD 北大核心 2019年第5期1197-1204,共8页
基于近15年的实测数据,分析给出了长江河口控制站徐六泾悬沙浓度和组成的变化特性。研究表明:徐六泾站多年平均表层(2003~2017年)、中层和底层(2010~2017年)含沙量分别为0.07、0.07和0.13 g/L;表层(2004~2017年)、中层和底层(2009~2017... 基于近15年的实测数据,分析给出了长江河口控制站徐六泾悬沙浓度和组成的变化特性。研究表明:徐六泾站多年平均表层(2003~2017年)、中层和底层(2010~2017年)含沙量分别为0.07、0.07和0.13 g/L;表层(2004~2017年)、中层和底层(2009~2017年)的中值粒径分别为7.3、9.4和11.0μm。研究期间,年平均含沙量呈显著下降趋势,洪季较枯季降幅更明显。其中2015~2017年均洪枯季表层含沙量较2003~2005年均值分别降低了57%和20%;表层含沙量在2008年出现明显降低的拐点,2008年之后的洪枯季表层含沙量较之前分别降低56%和44%。悬沙粒度具有一定的波动变化,但没有显著趋势性变化特征,或与样本数量限制和流域内人类活动有关。 展开更多
关键词 长江河口 徐六泾 悬移质泥沙 含沙量 粒度
三峡水库区间来沙量估算及水库排沙效果分析 预览
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作者 刘尚武 张小峰 +2 位作者 许全喜 张欧阳 黄俊健 《湖泊科学》 EI CAS CSCD 北大核心 2019年第1期28-38,共11页
三峡水库是控制和开发长江的重要工程,具有巨大的防洪、发电、航运等综合效益.水库排沙比是反映水库拦截泥沙程度的重要指标.针对目前三峡水库排沙比计算没有考虑三峡水库区间来沙,结果偏大的问题,依据三峡水库区间水文站2003-2016年实... 三峡水库是控制和开发长江的重要工程,具有巨大的防洪、发电、航运等综合效益.水库排沙比是反映水库拦截泥沙程度的重要指标.针对目前三峡水库排沙比计算没有考虑三峡水库区间来沙,结果偏大的问题,依据三峡水库区间水文站2003-2016年实测水文资料,采用水文学法估算了三峡水库区间月、年入库输沙量,分析了三峡水库排沙效果及主要影响因素.结果表明:1)三峡水库区间年均来沙量约1775×10^4t,占总入库沙量的10.3%,近年来沙占比有所增大,其中2013-2016年来沙量占总入库沙量的26.9%;2)三峡水库年均排沙比为21.6%,其中围堰蓄水期为34.1%,初期蓄水期为17.0%,试验性蓄水期为15.4%;3)三峡水库采用"蓄清排浑"方式运行,主汛期7-9月的排沙比一般大于枯季,但2013年以后,出现了主汛期排沙比小于枯季的现象;4)入库细颗粒泥沙的排沙比大于粗颗粒泥沙,其中粒径d≤0.062mm的细颗粒泥沙排沙比为23.4%,0.062mm<d≤0.125mm和d>0.125mm的中粗沙排沙比分别为5.5%和11.1%;5)三峡水库排沙比汛期主要受V/Q影响,枯季主要受入库含沙量的影响;当V/Q约为170×10^4s时,水库排沙效果最差;分别建立了汛期和枯季排沙比经验计算式.本文的研究成果可为三峡水库水沙优化调度等提供参考. 展开更多
关键词 悬移质 排沙比 来沙量 三峡水库区间
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Turbulence and suspended sediment processes in the Garonne Rivertidal bore in November 2016 预览
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作者 David Reungoat Xinqian Leng Hubert Chanson 《国际泥沙研究:英文版》 SCIE 2019年第5期496-508,共13页
A tidal bore is a water discontinuity at the leading edge of a ood tide wave in estuaries with a large tidal range and funneling topography. New measurements were done in the Garonne River tidal bore on 14 15 November... A tidal bore is a water discontinuity at the leading edge of a ood tide wave in estuaries with a large tidal range and funneling topography. New measurements were done in the Garonne River tidal bore on 14 15 November 2016, at a site previously investigated between 2010 and 2015. The data focused on long, continuous, high-frequency records of instantaneous velocity and suspended sediment con- centration (SSC) estimate for several hours during the late ebb, tidal bore passage and ood tide. The bore passage drastically modi ed the ow eld, with very intense turbulent and sediment mixing. This was evidenced with large and rapid uctuations of both velocity and Reynolds stress, as well as large SSCs during the ood tide. Granulometry data indicated larger grain sizes of suspended sediment in water samples compared to sediment bed material, with a broader distribution, shortly after the tidal bore. The tidal bore induced a sudden suspended sediment ux reversal and a large increase in suspended sedi- ment ux magnitude. The time-variations of turbulent velocity and suspended sediment properties indicated large uctuations throughout the entire data set. The ratio of integral time scales of SSC to velocity in the x-direction was on average TE,SSC/TE,x 0.16 during the late ebb tide, compared to TE,SSC/ TE,x 0.09 during the late ood tide. The results imply different time scales between turbulent velocities and suspended sediment concentrations. 展开更多
关键词 TIDAL BORE Garonne RIVER HYDRODYNAMICS Suspended SEDIMENT Field observations Turbulence-sediment suspension interactions
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Numerical Study on Seasonal Transportation of the Suspended Sediments in the Modern Yellow River Mouth Effected by the Artificial Water and Sediment Regulation 预览
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作者 WANG Nan QIAO Lulu +5 位作者 LI Guangxue ZHONG Yi SONG Dehai DING Dong GAO Fei JI Fengying 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第1期20-30,共11页
Since 2002,an artificial water and sediment regulation(AWSR)has been carried out,which largely reduced water and sediment discharged from the Yellow River into the Bohai Sea.Although the sediment transport in the Yell... Since 2002,an artificial water and sediment regulation(AWSR)has been carried out,which largely reduced water and sediment discharged from the Yellow River into the Bohai Sea.Although the sediment transport in the Yellow River Mouth(YRM)has been observed and modeled intensively since AWSR,but preferentially for the non-storm conditions.In this study,a three-dimensional current-wave-sediment coupled model,DHI-MIKE numerical model,was used to examine the seasonal suspended-sediment transport in the YRM after the AWSR.Results show that the seasonal distribution of suspended-sediments in the YRM is dominated by wind and wave rather than river input.The major transport pathway of suspended-sediments is from the western Laizhou Bay to the Bohai Strait during the winter monsoon,especially in storm events.In addition,about 66%of the river sediments deposit within 30km of the YRM,which is smaller than previous estimations.It suggests that the YRM has been eroded in recent decades. 展开更多
关键词 YELLOW River MOUTH artificial water and SEDIMENT regulation MIKE suspended-sediment transport SEASONAL variation
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Mechanism of Phase Lag Between Current Speed and Suspended Sediment:Combined Effect of Erosion,Deposition,and Advection 预览
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作者 ZHU Zichen WANG Yongzhi +3 位作者 HU Zejian BIAN Shuhua ZHANG Yongqiang XIONG Congbo 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第1期43-56,共14页
To retrieve and explain the phase lag between current speed and suspended sediment concentration(SSC),erosion,deposition,and advection were isolated as primary processes of sediment movement in a three-dimensional mod... To retrieve and explain the phase lag between current speed and suspended sediment concentration(SSC),erosion,deposition,and advection were isolated as primary processes of sediment movement in a three-dimensional model.The response time was proved to be one of the reasons for the phase lag,as time is needed for suspension to diffuse from bottom to surface.A fitted Shields diagram was introduced into the model to reflect the relationship between SSC and shear stress,between shear stress and critical shear stress,as well as between SSC and critical shear stress for erosion.It takes some time for shear stress to increase to the critical value after high or low tide,and this was proved to be an important contributor to the phase lag.Overall,the variation of vertically integrated SSC is influenced by erosion mass flux,deposition mass flux,and advection flux.The phase pattern of erosion mass flux is consistent with the pattern of current if there was no wave action.However,phase difference is produced by the influence of deposition mass flux and advection.In this study,SSC peak/trough mostly occurred near the moment erosion mass flux approximately equaled deposition mass flux and would be impacted by advection.The time required for instantaneous variation of suspension to get to 0 after current peak/trough represents the phase lag between current speed and SSC. 展开更多
关键词 phase LAG SEDIMENT transport critical SHEAR stress suspended SEDIMENT
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江苏射阳南区海域海洋悬沙粒度分析 预览
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作者 晏彪 袁震洲 +1 位作者 李厚贵 朱俊 《科技创新与应用》 2019年第19期85-87,91共4页
通过布设的悬沙采集站点获取的120个悬沙粒度样品,对江苏射阳南区海域的海洋悬沙类型、粒级组成、含量及平均粒径、分选系数、偏差、峰态、中值等粒度参数进行了统计分析,揭示了悬沙在冬、夏季大、中、小潮期间不同的特性,分析结果对工... 通过布设的悬沙采集站点获取的120个悬沙粒度样品,对江苏射阳南区海域的海洋悬沙类型、粒级组成、含量及平均粒径、分选系数、偏差、峰态、中值等粒度参数进行了统计分析,揭示了悬沙在冬、夏季大、中、小潮期间不同的特性,分析结果对工程设计和施工具有重要的指导意义。 展开更多
关键词 海洋水文 悬沙 粒度参数 统计分析
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三峡工程蓄水以来九江-湖口河段河道冲淤分析 预览
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作者 罗红雨 曹双 方波 《科技风》 2019年第8期216-217,共2页
三峡工程于2003年6月进入围堰发电期。汛期按135.0m运行,枯季按139.0m水位运行;2006年汛后实施二期蓄水。为动态了解三峡水库蓄水后坝下游河道的冲淤变化情况,同时为更好地满足三峡水库科学调度的需要,本文系统的分析了宏观环境的改变... 三峡工程于2003年6月进入围堰发电期。汛期按135.0m运行,枯季按139.0m水位运行;2006年汛后实施二期蓄水。为动态了解三峡水库蓄水后坝下游河道的冲淤变化情况,同时为更好地满足三峡水库科学调度的需要,本文系统的分析了宏观环境的改变及河道地形的冲淤:三峡工程蓄水前后大通水文站及九江水文站水、沙变化情况,并依据2016年10月九江至湖口河段固定断面观测资料,和2017年河道地形观测资料,分析2017年度九江至湖口河段河床冲淤变化情况。结果表明:三峡工程蓄水以来,上游来水量略减、来沙量锐减,该段河道近期略有微淤,但总体处于冲刷态势,主要冲淤发生在河槽部位。 展开更多
关键词 三峡工程 河道演变 径流量 悬移质 输沙量
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闽江口B6区块采砂悬浮泥沙扩散数值模拟研究 预览
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作者 余钦明 《渔业研究》 2019年第3期195-206,共12页
本文基于非结构网格有限体积的FVCOM海洋模型,应用已建立的悬浮泥沙扩散方程对FVCOM模型中的悬浮泥沙模型进行了修改,构建了闽江口附近海域潮汐潮流悬浮泥沙模拟模型。应用闽江口实测潮汐潮流数据对模型开展了验证,验证结果表明模型可... 本文基于非结构网格有限体积的FVCOM海洋模型,应用已建立的悬浮泥沙扩散方程对FVCOM模型中的悬浮泥沙模型进行了修改,构建了闽江口附近海域潮汐潮流悬浮泥沙模拟模型。应用闽江口实测潮汐潮流数据对模型开展了验证,验证结果表明模型可以较好地模拟闽江口潮汐潮流运动特征,可以用于开展B6区块海域采砂悬浮泥沙扩散的模拟研究工作。采用建立的数学模型对不同采砂方案引起的悬浮泥沙运动扩散进行了数值模拟计算,计算过程中针对不同采砂启动时刻,分别设定涨急和落急时刻,分析悬浮泥沙最大影响范围,给出10、50、100mg/L悬浮泥沙等值线图。悬浮泥沙影响范围的计算结果表明,悬浮泥沙对周围海洋环境敏感保护目标影响小。 展开更多
关键词 悬浮泥沙 潮汐潮流 采砂 数值模拟 FVCOM
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半日潮流作用下悬移质泥沙的运动特征及其影响因素研究 预览
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作者 朱子晨 张莞君 +2 位作者 胡泽建 刘建强 熊丛博 《海洋学报》 CAS CSCD 北大核心 2019年第6期37-47,共11页
本文通过建立一维水深平均悬沙模型,对典型潮流控制的水道内悬沙运动特征进行研究。模型以泥沙再悬浮、沉降和平流为主要物理过程,动力因素包含M2、S2分潮及余流,采用湄洲湾2007年8月潮位、潮流、悬沙、底质同步观测资料进行分析和验证... 本文通过建立一维水深平均悬沙模型,对典型潮流控制的水道内悬沙运动特征进行研究。模型以泥沙再悬浮、沉降和平流为主要物理过程,动力因素包含M2、S2分潮及余流,采用湄洲湾2007年8月潮位、潮流、悬沙、底质同步观测资料进行分析和验证。通过三角傅里叶分析,将悬沙的时间序列分解为12个主要的谐波分量,其中主要分量包括:M2分潮作用下产生的具有M2倍潮角速度的1/4日分潮项,M2与S2分潮共同作用下且角速度为两分潮角速度之和的1/4日分潮项,及水平悬沙梯度、余流与M2分潮共同作用下具有M2分潮角速度的半日潮项。悬沙在时间上的平均值受到余流、悬沙水平梯度、M2分潮流及悬沙起动条件等因素控制。余流导致了悬沙序列中相邻周期之间的不对称性。反映泥沙特性的参量对悬沙的曲线特征具有重要影响,泥沙沉降速度影响悬沙的相位,并影响其振幅;再悬浮有关的参量仅影响各谐波分量的振幅,但不影响相位。 展开更多
关键词 悬移质泥沙 三角傅里叶分析 再悬浮 M2分潮 S2分潮 余流
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The impact of climate change and human activities on streamflow and sediment load in the Pearl River basin 预览
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作者 Chuangshou Wu Changchen Ji +4 位作者 Benwei Shi Yaping Wang Jianhua Gao Yang Yang Jinbin Mu 《国际泥沙研究:英文版》 SCIE 2019年第4期307-321,共15页
This paper uses monthly streamflow, suspended sediment concentration, and meteorological data to examine the impact of human activity and climate change on streamflow and sediment load in the Pearl River basin from th... This paper uses monthly streamflow, suspended sediment concentration, and meteorological data to examine the impact of human activity and climate change on streamflow and sediment load in the Pearl River basin from the 1950s to the 2000s. The influences of climate change and human activities on hydrological processes were quantitatively evaluated using the Mann–Kendall abrupt change test and power rating curves. The results showed that:(1) abrupt changes and turning points in streamflow occurred in 1963, 1983, and 1991 which were found to be consistent with global ENSO events and volcanic eruptions. However, abrupt changes in sediment load showed significant spatial differences across the Pearl River basin. For the Xijiang River, an abrupt change in sediment load occurred in 2002, and after 2007 the change becomes significant at the 95% confidence level. At Beijiang and Dongjiang, abrupt changes in sediment load occurred in 1998 and 1988, respectively.(2) The time series of sediment load data was divided into four periods according to abrupt changes. The contribution of climate change and human activities is different in the different rivers. For the Xijiang River, compared with the first period, climate change and human activities contributed 83% and 17%, respectively, to the increasing sediment load during the second period. In the third period, the variation of sediment load followed a decreasing trend. The contribution from climate change and human activities also changed to t236% and -136%, respectively. In the fourth period, climate change and human activities contributed -32% and t132%, respectively. Meanwhile, For the Beijiang River, climate change and human activities contributed 90% and 10% in the second period, the contribution of climate change increased to t115% and human activities decreased to -15% in the third period. In the fourth period, the value for climate change decreased to t36% and human activities increased to t64%. For the Dongjiang River, the contribution of human activities was from 展开更多
关键词 PEARL river Streamflow Suspended sediment concentration Climate change Human activities MANN-KENDALL test
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Response of the sediment geochemistry of the Changjiang River(Yangtze River) to the impoundment of the Three Gorges Dam
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作者 Hao Wang Xiangbin Ran +4 位作者 Jingxi Li Jun Liu Wentao Wu Menglu Li Jiaye Zang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第9期161-173,共13页
Based on the measurement of major and trace elements in suspended sediments in the low reaches of the Changjiang River during throughout a whole hydrologic year, the origins, seasonal variations, and fluxes of multiel... Based on the measurement of major and trace elements in suspended sediments in the low reaches of the Changjiang River during throughout a whole hydrologic year, the origins, seasonal variations, and fluxes of multielements and the human impacts on multielements transport processes have been analyzed along with the influence of weathering in the Changjiang River basin. The results show that most element contents were high in both autumn and winter and low in summer, which was largely caused by the dilution of discharge. Weathering detritus in the Changjiang River basin is the main source of most elements in suspended sediments. However, riverine pollution could bring more loadings of Cd, Pb, As and Zn into river water than it did a few decades ago. The annual average fluxes of Cd, Pb and Zn, which are major contamination elements, to the sea were 179 ± 21 tons/year, 7810 ± 675 tons/year, and 12,000 ± 1320 tons/year,respectively, in which approximately 8.7%, 11.9% and 2.7% of their loadings, respectively,were contributed by pollution inputs. Element exports mainly occurred in the summer(44.4%–57.4%) in the lower part of the Changjiang River. A general relationship between sediment retention and element content suggests a positive feedback mechanism for the decreased number of particles, in which element riverine loadings are reduced due to the enhanced trapping effect by the Three Gorges Dam(TGD). Compared to those in 1980,current element shares of the Changjiang River compared to the global budget have declined due to the construction of the TGD. 展开更多
关键词 CHANGJIANG RIVER Suspended SEDIMENT Metal ELEMENT Human activity TGD
山东半岛东部海域泥质区冬季悬浮泥沙时空变化及输运机制 预览 被引量:1
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作者 冷星 朱龙海 胡日军 《中国海洋大学学报:自然科学版》 CAS CSCD 北大核心 2019年第4期106-116,8共12页
根据2015年12月山东半岛东部海域4个站位25 h同步连续定点海流观测和悬浮泥沙取样资料,分析了研究区悬浮泥沙浓度、粒度时空分布特征和变化规律;通过计算再悬浮与沉积通量、理查森数并结合通量机制分解法,探讨了影响悬浮泥沙变化的因素... 根据2015年12月山东半岛东部海域4个站位25 h同步连续定点海流观测和悬浮泥沙取样资料,分析了研究区悬浮泥沙浓度、粒度时空分布特征和变化规律;通过计算再悬浮与沉积通量、理查森数并结合通量机制分解法,探讨了影响悬浮泥沙变化的因素,揭示了悬沙输运机制。结果表明,涨潮时段悬浮泥沙浓度略大于落潮时段,悬浮泥沙浓度与潮流流速大致呈正相关关系,且存在轻微的滞后现象;悬浮泥沙类型均为粘土质粉砂,分选差,存在再悬浮现象;悬浮泥沙垂向混合剧烈,个别时段有轻微的层化现象,平流输运是造成该海域悬浮泥沙输运的最主要因素。 展开更多
关键词 山东半岛 悬浮泥沙 泥质沉积体 再悬浮 通量机制分解
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Determination of the particle load based on detailed suspended sediment measurements at a hydropower plant 预览
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作者 Anant Kumar Rai Arun Kumar 《国际泥沙研究:英文版》 SCIE 2019年第5期409-421,共13页
Suspended sediment particles contained in inflows of water systems of hydropower plants (HPPs) cause hydro-abrasive erosion of the hydraulic turbines and structures leading to significant maintenance costs, efficiency... Suspended sediment particles contained in inflows of water systems of hydropower plants (HPPs) cause hydro-abrasive erosion of the hydraulic turbines and structures leading to significant maintenance costs, efficiency reductions, and downtime. Relevant parameters such as suspended sediment concentration (SSC), particle size distribution (PSD), shape, and mineralogical composition were measured with an online multi-frequency acoustic instrument and based on manually taken samples from the end of the sand trap of the Toss HPP in the Himalayan region, India. In the laboratory, the samples were analyzed using the gravimetric method, laser diffraction, turbidity, dynamic digital image processing, scanning electron microscope, petrography analysis, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The online instrument and the samples provided measurement results at a single point. To investigate vertical gradients in concentration and particle sizes, additional samples were collected 9 times at 7 relative water depths. The SSC, most particle sizes, and particle shape were found to be evenly distributed over depth except d90, i.e. the diameter which is not exceeded by 90% of the particle mass. d90 measured at 76% of the water depth was in the range of fine sand and was multiplied by 1.05 to obtain an average value representative for the entire depth. Improved methodologies to quantify both particle shape and size in an analytical model for hydro-abrasive erosion are proposed. Also, the PSD measuring performance of laser diffraction and dynamic imaging was studied and similar values of the median particle sizes were obtained from both instruments. Further, multi-frequency acoustic, turbidity and laser diffraction techniques were found suitable for SSC measurement at the test case HPP. 展开更多
关键词 Suspended sediment concentration Hydro-abrasive EROSION HYDROPOWER PARTICLE size distribution PARTICLE shape MINERALOGICAL composition
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A SEM-based method to determine the mineralogical composition and the particle size distribution of suspended sediment 预览
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作者 Sylvain Pinet Bruno Lartiges +1 位作者 Jean-Michel Martinez Sylvain Ouillon 《国际泥沙研究:英文版》 SCIE 2019年第2期85-94,共10页
A robust method for characterizing the mineralogy of suspended sediment in continental rivers is introduced. It encompasses 3 steps: the filtration of a few milliliters of water, measurements of X-ray energy dispersiv... A robust method for characterizing the mineralogy of suspended sediment in continental rivers is introduced. It encompasses 3 steps: the filtration of a few milliliters of water, measurements of X-ray energy dispersive spectra using Scanning Electron Microscopy (SEM), and robust machine learning tools of classification. The method is applied to suspended particles collected from various Amazonian rivers. A total of more than 204,000 particles were analyzed by SEM-EDXS (Energy Dispersive X-ray Spectroscopy), i.e. about 15,700 particles per sampling station, which lead to the identification of 15 distinct groups of mineralogical phases. The size distribution of particles collected on the filters was derived from the SEM micrographs taken in the backscattered electron imaging mode and analyzed with ImageJ freeware. The determination of the main mineralogical groups composing the bulk sediment associated with physical parameters such as particle size distribution or aspect ratio allows a precise characterization of the load of the terrigenous particles in rivers or lakes. In the case of the Amazonian rivers investigated, the results show that the identified mineralogies are consistent with previous studies as well as between the different samples collected. The method enabled the evolution of grain size distribution from fine to coarse material to be described in the water column. Implications about hydrodynamic sorting of mineral particles in the water column are also briefly discussed. The proposed method appears well suited for intensive routine monitoring of suspended sediment in river systems. 展开更多
关键词 MINERALOGY SCANNING ELECTRON MICROSCOPY Suspended SEDIMENT Machine learning PARTICLE size distribution
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Artificial neural network simulation for prediction of suspended sediment concentration in the River Ramganga, Ganges Basin, India 预览
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作者 Mohd Yawar Ali Khan Fuqiang Tian +1 位作者 Faisal Hasan Govind Joseph Chakrapani 《国际泥沙研究:英文版》 SCIE 2019年第2期95-107,共13页
The relation between the water discharge (Q) and suspended sediment concentration (SSC) of the River Ramganga at Bareilly, Uttar Pradesh, in the Himalayas, has been modeled using Artificial Neural Networks (ANNs). The... The relation between the water discharge (Q) and suspended sediment concentration (SSC) of the River Ramganga at Bareilly, Uttar Pradesh, in the Himalayas, has been modeled using Artificial Neural Networks (ANNs). The current study validates the practical capability and usefulness of this tool for simulating complex nonlinear, real world, river system processes in the Himalayan scenario. The modeling approach is based on the time series data collected from January to December (2008-2010) for Q and SSC. Three ANNs (T1-T3) with different network configurations have been developed and trained using the Levenberg Marquardt Back Propagation Algorithm in the Matlab routines. Networks were optimized using the enumeration technique, and, finally, the best network is used to predict the SSC values for the year 2011. The values thus obtained through the ANN model are compared with the observed values of SSC. The coefficient of determination (R2), for the optimal network was found to be 0.99. The study not only provides insight into ANN modeling in the Himalayan river scenario, but it also focuses on the importance of understanding a river basin and the factors that affect the SSC, before attempting to model it. Despite the temporal variations in the study area, it is possible to model and successfully predict the SSC values with very simplistic ANN models. 展开更多
关键词 ANN Water DISCHARGE Suspended SEDIMENT concentration PREDICTION Ramganga RIVER HIMALAYAS
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The influence of runoff and wind on the dispersion patterns of suspended sediment in the Zhujiang(Pearl) River Estuary based on MODIS data 预览
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作者 Suying Ou Qingshu Yang +3 位作者 Xiangxin Luo Fan Zhu Kaiwen Luo Hao Yang 《海洋学报:英文版》 SCIE CAS CSCD 2019年第3期26-35,共10页
Cloud-free moderate-resolution imaging spectroradiometer(MODIS) images of the Zhujiang(Pearl) River Estuary(ZRE) taken between 2002 and 2012 are retrieved and used to study the spatial and temporal patterns of suspend... Cloud-free moderate-resolution imaging spectroradiometer(MODIS) images of the Zhujiang(Pearl) River Estuary(ZRE) taken between 2002 and 2012 are retrieved and used to study the spatial and temporal patterns of suspended sediment concentrations(SSCs) across the estuary under runoff, wind, and tropical storm conditions.Five typical dispersal patterns of suspended sediments in the estuary are defined: Case I shows generally low SSCs under low dynamics;Case Ⅱ shows a river-dominant dispersal pattern of suspended sediments from the outlets,particularly from Modaomen, Jiaomen, Hengmen, and others;Case Ⅲ shows wind-dominant dispersal of high SSCs derived from the west shoal and southwesterly transport under a strong NE wind;Case IV is the combination of relatively large runoff and wind;and Case V is caused by a strong tropical storm with high river discharge and wind, which is characterized by the high SSCs across the entire estuary that are transported eastward by winddriven and buoyancy currents outside the estuary. Runoff is a dominant factor that controls seasonal and annual SSC variations in the ZRE, with the area of high SSCs being largest in the summer and smallest in the spring. The correlation coefficients between the monthly averaged river-suspended sediment discharge and the area of the high SSCs are approximately 0.6. The wind power over the west shoal increases with a wind speed, which induces more sediment resuspension and shows a close relationship between the wind speed and high SSC area. 展开更多
关键词 Zhujiang(Pearl) River ESTUARY suspended sediment concentration(SSC) moderate-resolution imaging SPECTRORADIOMETER WIND RUNOFF TIDES
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Ⅱ类水体悬移质泥沙含量遥感反演综述 预览
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作者 杨佳 范建容 +2 位作者 张茜彧 于江 朱昕 《人民长江》 北大核心 2019年第7期98-103,共6页
悬移质泥沙是水环境的重要参数之一,其含量的变化对流域生态环境有着多方面的影响。传统研究方法能够实现悬移质泥含量的精确分析,但存在布点有限、时效不足等问题,而遥感技术可弥补传统研究方法的不足,实现大面积水域的同步观测。基于... 悬移质泥沙是水环境的重要参数之一,其含量的变化对流域生态环境有着多方面的影响。传统研究方法能够实现悬移质泥含量的精确分析,但存在布点有限、时效不足等问题,而遥感技术可弥补传统研究方法的不足,实现大面积水域的同步观测。基于悬移质泥沙含量遥感反演的4类模型:物理模型、半分析模型、经验模型、人工智能算法模型,总结了Ⅱ类水体悬移质泥沙含量遥感反演的研究进展,探讨了反演研究中存在的离水辐亮度提取难度大、混合像元不易分解等问题,并针对我国内陆山区河流,提出山区Ⅱ类水体悬移质泥沙含量遥感反演发展面临的关键问题。 展开更多
关键词 Ⅱ类水体 悬移质泥沙 卫星遥感 反演模型 内陆山区河流
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基于蚁群算法的超声波水体悬移质浓度测量研究 预览
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作者 张述仁 徐雅 +3 位作者 谢代梁 徐志鹏 刘铁军 王月兵 《传感技术学报》 CAS CSCD 北大核心 2019年第8期1163-1168,共6页
水体悬移质浓度测量是水文观测的重要内容之一,对于我国水资源的保护和管理具有重大意义。现有的测量方法不能同时满足实时、高精度、大量程等测量需求,针对悬移质浓度测量中颗粒粒径分布与浓度相互耦合的问题,提出了基于蚁群算法的超... 水体悬移质浓度测量是水文观测的重要内容之一,对于我国水资源的保护和管理具有重大意义。现有的测量方法不能同时满足实时、高精度、大量程等测量需求,针对悬移质浓度测量中颗粒粒径分布与浓度相互耦合的问题,提出了基于蚁群算法的超声波水体悬移质浓度测量方法。搭建了超声波水体悬移质参数测量系统,对不同粒径、不同浓度的悬移质水样进行了超声衰减实验,并采用蚁群算法对水体悬移质浓度进行了反演。研究表明:当蚂蚁数量为20、蚂蚁最大移动次数为90、转移概率为0.6、信息素挥发系数为0.4时,蚁群算法的性能达到最佳,三种粒径下各组水样的测量浓度相对误差分布分别为±10%、±13%、±15%,实验结果与参考值较为一致,该方法可为悬移质浓度测量提供一定的借鉴。 展开更多
关键词 超声波 蚁群算法 悬移质 浓度 固液两相流
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植被群落对悬移质沉积的影响研究 预览
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作者 张斌 马旭东 《实验科学与技术》 2019年第4期15-18,39,共5页
目前针对水流中悬移质泥沙沉积量的观测方法相对较少,该文首先提出了一种采用可移动玻璃片收集沉积的悬移质,再配合烘干机、精密天平等仪器观测悬移质泥沙净沉积量的方法。然后将该方法用于观测植被群落对悬移质泥沙淤积量与淤积分布的... 目前针对水流中悬移质泥沙沉积量的观测方法相对较少,该文首先提出了一种采用可移动玻璃片收集沉积的悬移质,再配合烘干机、精密天平等仪器观测悬移质泥沙净沉积量的方法。然后将该方法用于观测植被群落对悬移质泥沙淤积量与淤积分布的影响。研究发现,在植被群落尾端会存在一个悬移质沉积区,紧接着会出现一个沉积量减小的区域,经分析认为该现象与植被群落后端的卡门涡街影响密不可分。该观测方法实现了对水槽内水沙循环过程中悬移质沉积量的有效且准确采集,并可为污染物落淤研究等方面的观测方法提供参考。 展开更多
关键词 水槽试验 悬移质 测量方法 植被群落 卡门涡街
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水源水库季节性分层及悬浮物行为对铁锰迁移的影响——以辽宁省碧流河水库为例 预览
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作者 姜欣 朱林 +1 位作者 许士国 谢在刚 《湖泊科学》 EI CAS CSCD 北大核心 2019年第2期375-385,共11页
铁和锰是氧化还原敏感的元素,水源水库热分层引起的底层水体缺氧造成了沉积物中铁和锰的释放,对城市供水造成了极大的影响.以往鲜有悬浮物行为对铁和锰在水库水-沉积物界面迁移影响的研究,于2014年2月-2015年2月对碧流河水库深水区的水... 铁和锰是氧化还原敏感的元素,水源水库热分层引起的底层水体缺氧造成了沉积物中铁和锰的释放,对城市供水造成了极大的影响.以往鲜有悬浮物行为对铁和锰在水库水-沉积物界面迁移影响的研究,于2014年2月-2015年2月对碧流河水库深水区的水、悬浮物以及沉积物铁和锰的垂向分布特征进行综合调查分析,并进一步分析铁和锰的季节性变化规律及悬浮物行为对其的影响. Spearman相关分析结果表明铁浓度与总悬浮固体、总氮和总磷的相关性较大;锰浓度与总悬浮固体、溶解氧、pH和总氮的相关性较大.进一步讨论分析表明碧流河水库的热分层、底层缺氧以及沉积物再悬浮是影响铁和锰浓度的重要因素,水库铁和锰的季节变化规律存在差异.分层期溶解态的锰在底层累积,平均浓度达到0.18 mg/L,而沉积物中溶解态的铁释放很少.混合期水库的中上层锰浓度升高,达到了0.07 mg/L.沉积物的再悬浮是水库底层水体中铁的主要来源,底层颗粒态铁的平均浓度约为0.3 mg/L.絮凝的颗粒物以及其吸附的锰在水库长期悬浮,难以沉积到水库底部,使得悬浮物中Mn的含量显著高于表层沉积物,约为沉积物的7倍.建议应在碧流河水库采用分层取水、水库曝气以及联合供水等措施,以减少铁和锰的浓度升高对供水产生的影响,保障大连市城市供水安全. 展开更多
关键词 悬浮物 分层 水源水库 碧流河水库
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