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黄土区工程堆积体陡坡坡面径流调控工程措施的减沙效应 预览
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作者 张乐涛 董俊武 +7 位作者 袁琳 朱雅琴 黄增玉 李婉璐 王慧慧 唐林昊 田红卫 高照良 《农业工程学报》 EI CAS CSCD 北大核心 2019年第15期101-109,共9页
定量分析减少径流和改变水沙关系在泥沙调控中的不同作用,对于深刻理解径流调控措施的水土保持效益具有重要意义。以黄土区工程堆积体陡坡坡面(36°)为例,探讨了野外模拟径流冲刷试验条件下,不同工程措施及其组合调控坡面径流的水... 定量分析减少径流和改变水沙关系在泥沙调控中的不同作用,对于深刻理解径流调控措施的水土保持效益具有重要意义。以黄土区工程堆积体陡坡坡面(36°)为例,探讨了野外模拟径流冲刷试验条件下,不同工程措施及其组合调控坡面径流的水沙效应及其作用效率。结果表明:1)不同工程措施均能较好地调控坡面径流侵蚀过程,不同情形下的产流时间控制比为2~20,径流量控制比为0.45~0.78,产沙量控制比为0.20~0.59;平均含沙量控制比为0.38~0.79;2)减流控沙作用是工程措施调控坡面侵蚀产沙的主要原因,水沙关系调沙作用则受减流控沙作用的制约;3)水平阶类措施的水沙关系调沙量与减流控沙量呈线性正相关,当减流控沙量超过一定临界值时,水沙关系才开始发挥调沙作用;水平沟类措施的水沙关系调沙量与减流控沙量呈二次函数关系,水沙关系调沙量存在极大值;4)水平沟类措施调控泥沙的作用效率高于水平阶类措施,水平沟+鱼鳞坑的组合可很好地发挥减流控沙和水沙关系调沙作用的潜力(55%),使二者在较高的水平上维持相对平衡;因此,不同工程措施与组合的实际应用应以具体的水土保持效益和防治目标为布设依据。研究可为堆积体陡坡治理的工程措施优化提供理论参考。 展开更多
关键词 侵蚀 泥沙 径流 水沙关系 泥沙调控能力 效率系数 弃土堆积体
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Development of benthic macroinvertebrates sediment index (BSI) for bioassessment of freshwater sediment 预览
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作者 Pil Jae Kim Jong Hyeon Lee +1 位作者 In Ae Huh DongSoo Kong 《国际泥沙研究:英文版》 SCIE 2019年第4期368-378,共11页
Sediment quality has been evaluated in a variety of ways since the early 1990s in studies from Europe. In South Korea, most studies have used an indicator value for benthic macroinvertebrates based on water quality, n... Sediment quality has been evaluated in a variety of ways since the early 1990s in studies from Europe. In South Korea, most studies have used an indicator value for benthic macroinvertebrates based on water quality, not sediment quality. To date, few studies have examined the biological integrity of benthic macroinvertebrate communities in South Korea. In the current study, the tolerance valency and value in samples and the indicator weight values were measured for 43 benthic macroinvertebrate taxa from 73 sampling units in South Korea from 2014 to 2016. Total organic carbon, the amount of heavy metals, and total ammonia nitrogen were analyzed. The average grade for each pollutant was used as the sediment quality index. A benthic macroinvertebrates sediment index was developed for bioassessment of freshwater sediment. The benthic macroinvertebrates sediment index, which is based on the relative frequency of occurrence of macroinvertebrates, was highly correlated with pollution levels in the sediment. This index can be used in the field to assess the contamination of freshwater sediment. As the sample size was small in the current study and there were taxonomic limitations of Chironomidae larvae, further research is needed to improve the reliability of the benthic macroinvertebrates sediment index. 展开更多
关键词 BENTHIC MACROINVERTEBRATES BIOASSESSMENT FRESHWATER SEDIMENT SEDIMENT quality INDEX
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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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Development and Application of an in Situ Penetrator for Rapid Strength Testing of Submarine Sediment 预览
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作者 ZHANG Minsheng WANG Zhenhao +2 位作者 WANG Xiuhai WEN Mingzheng HONG Bo 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期328-338,共11页
In marine engineering,the strength of a submarine sediment is an indispensable parameter for assessment of construction.In this study,a free-fall cone penetrator named IPen was developed to realize a rapid and efficie... In marine engineering,the strength of a submarine sediment is an indispensable parameter for assessment of construction.In this study,a free-fall cone penetrator named IPen was developed to realize a rapid and efficient measurement of sediment strength.The equipment is characterized by modular design and self-contained data acquisition.It is equipped with an acceleration sensor,a water pressure sensor,and a piezocone penetration test(CPTu)probe.It is designed to be released from near seabed surface with a releaser and then fall freely to provide a higher penetration velocity.Its maximum working depth is approximately 2500m and maximum penetration depth is approximately 3 m.To derive the correlation between penetration resistance and sediment strength,a calibrator was devised to determine the penetration-rate factor.In addition,the factor applicable to in situ test points was determined in laboratory experiments.In June 2016,the IPen was tested in situ in the South Yellow Sea,China,during a shared voyage funded by the National Science Foundation.Meanwhile,undisturbed column samples were collected for laboratory tests.Based on the in situ test results,it was demonstrated that the IPen could accurately record the working states of various sensors during the freely falling course.IPen test results reliably reflected the sediment strength at all the testing points when compared with laboratory calibration tests,in situ vane tests and penetration tests,laboratory penetration tests,and unconsolidated and undrained triaxial compression tests. 展开更多
关键词 SUBMARINE SEDIMENT free-fall CONE PENETRATION test SEDIMENT strength the Yellow Sea penetration-rate factor
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夏季东、黄海沉积物中甲烷的分布和沉积物-水界面通量 预览
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作者 叶旺旺 谷雪霁 +2 位作者 康绪明 刘素美 张桂玲 《海洋科学》 CAS 北大核心 2019年第7期77-86,共10页
沉积物释放是海洋环境中甲烷(CH4)的重要来源。通过2013年7月和8月两个航次,对东、黄海泥质区沉积物中CH4浓度的垂直分布和沉积物-水界面通量进行了研究。结果表明,除个别站位外,黄海沉积物(50cm以浅)中CH4的浓度变化范围在0.2~1.0μmo... 沉积物释放是海洋环境中甲烷(CH4)的重要来源。通过2013年7月和8月两个航次,对东、黄海泥质区沉积物中CH4浓度的垂直分布和沉积物-水界面通量进行了研究。结果表明,除个别站位外,黄海沉积物(50cm以浅)中CH4的浓度变化范围在0.2~1.0μmol/L之间,长江口及浙闽沿岸附近的沉积物中CH4浓度则要更高(1.0~2.0μmol/L),而东海东部海域沉积物中CH4浓度波动范围为0.2~3.0μmol/L。总体来说,东、黄海沉积物中CH4浓度偏低,这可能与观测到的高浓度硫酸盐(>20mmol/L)有关。通过整柱密室培养实验估算出东、黄海沉积物-水界面CH4释放速率在0.64~2.12μmol/(m^2·d)之间,东、黄海沉积物CH4释放总量为6.7×10^8mol/yr;但采用菲克定律估算的CH4扩散通量则要比现场培养的结果低2~5倍,表明不同的方法在估算沉积物-水界面CH4通量上还具有一定的不确定性。 展开更多
关键词 东海 沉积物 甲烷 硫酸盐 沉积物-水界面通量
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基于小流域尺度的黔北喀斯特地区产流产沙特征 预览
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作者 李瑞 陈康 +4 位作者 刘瑞禄 顾再柯 文雅琴 黎庆贵 刘凤仙 《农业工程学报》 EI CAS CSCD 北大核心 2019年第11期139-147,共9页
目前,中国西南喀斯特地区流域尺度产流产沙长期定位观测试验报道较少,且其相关机制的探讨不足。该文基于小流域尺度,分析典型喀斯特小流域产流产沙特征,定性、定量探讨喀斯特小流域产流产沙的主要影响因子。选取位于贵州北部的典型喀斯... 目前,中国西南喀斯特地区流域尺度产流产沙长期定位观测试验报道较少,且其相关机制的探讨不足。该文基于小流域尺度,分析典型喀斯特小流域产流产沙特征,定性、定量探讨喀斯特小流域产流产沙的主要影响因子。选取位于贵州北部的典型喀斯特小流域-遵义浒洋水小流域为研究区,采用小流域控制站定位观测法,在4年连续观测的基础上,分析浒洋水小流域月际、年际产流产沙特征,并重点分析了降雨对小流域产流产沙的影响。结果表明:受喀斯特地区特殊的"二元"侵蚀环境等因素影响,浒洋水小流域产流、产沙高峰不同期,产流高峰出现在10月,多年月均值为63.9万m^3,而产沙高峰为6月,116.21t。显著性检验则表明,浒洋水小流域月际产流无显著差异(P>0.05),但6月产沙则显著高于1、2、3及12月(P<0.05),其他月份间产沙无显著差异(P>0.05);受年度降雨的影响,2010-2013年,无论是产流还是产沙,2013年均显著高于其他年份(P<0.05)。研究期间,小流域多年平均输沙模数为215.32 t/(km2·a),这一结果与贵州省公布的贵州喀斯特区土壤侵蚀模数279.47t/(km2·a)接近;该小流域降雨对产流产沙影响显著,降雨强度(I60)同产流产沙在0.05水平上显著相关,而降雨量同产流产沙则在0.01水平上显著相关。结果可为喀斯特地区的水土流失治理提供参考。 展开更多
关键词 流域 侵蚀 径流 喀斯特 黔北 坡面尺度 产沙 输沙模数 浒洋水
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Effects of rainfall patterns on runoff and rainfall-induced erosion 预览
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作者 Morteza Alavinia Farzin Nasiri Saleh Hossain Asadi 《国际泥沙研究:英文版》 SCIE 2019年第3期270-278,共9页
Rainfall-induced erosion involves the detachment of soil particles by raindrop impact and their transport by the combined action of the shallow surface runoff and raindrop impact.Although temporal variation in rainfal... Rainfall-induced erosion involves the detachment of soil particles by raindrop impact and their transport by the combined action of the shallow surface runoff and raindrop impact.Although temporal variation in rainfall intensity(pattern)during natural rainstorms is a common phenomenon,the available information is inadequate to understand its effects on runoff and rainfall-induced erosion processes.To address this issue,four simulated rainfall patterns(constant,increasing,decreasing,and increasing-decreasing)with the same total kinetic energy were designed.Two soil types(sandy and sandy loam)were subjected to simulated rainfall using 15 cm×30 cm long detachment trays under infiltration conditions.For each simulation,runoff and sediment concentration were sampled at regular intervals.No obvious difference was observed in runoff across the two soil types,but there were significant differences in soil losses among the different rainfall patterns and stages.For varying-intensity rainfall patterns,the dominant sediment transport mechanism was not only influenced by raindrop detachment but also was affected by raindrop-induced shallow flow transport.Moreover,the efficiency of equations that predict the interrill erosion rate increased when the integrated raindrop impact and surface runoff rate were applied.Although the processes of interrill erosion are complex,the findings in this study may provide useful insight for developing models that predict the effects of rainfall pattern on runoff and erosion. 展开更多
关键词 RAINFALL pattern SEDIMENT CONCENTRATION Soil LOSS SEDIMENT transport mechanisms
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典型盐碱地改良区农田排水沟水体与底泥界面氧通量研究 预览
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作者 潘延鑫 冯绍元 +2 位作者 罗纨 贾忠华 井思媛 《水利学报》 EI CSCD 北大核心 2019年第7期835-843,共9页
农田排水沟水体与底泥中的氧含量决定了底泥中各种生源要素的最终归趋,对维持农田排水沟的水环境至关重要。本论文以陕西富平县卤泊滩盐碱地改良区农田排水沟水体与底泥为研究对象,从环境微界面角度出发,根据多年监测数据构建室内试验,... 农田排水沟水体与底泥中的氧含量决定了底泥中各种生源要素的最终归趋,对维持农田排水沟的水环境至关重要。本论文以陕西富平县卤泊滩盐碱地改良区农田排水沟水体与底泥为研究对象,从环境微界面角度出发,根据多年监测数据构建室内试验,采用高分辨率微环境固液剖面传感系统(丹麦Unisense微电极系统),探究了研究区农田排水沟水体与底泥界面氧通量变化规律。研究结果表明:底泥中的溶解氧随深度的增加逐渐减小,直至溶解氧浓度为零,到达厌氧层;溶解氧剖面浓度的实测值与Profile模型模拟值的相关系数均在0.995以上,表明该模型能客观地描述溶解氧在农田排水沟水体与底泥扩散边界层和底泥中的分布;农田排水沟上游不同监测点位的底泥含氧层厚度在3.5~6 mm之间,而下游监测点位的底泥含氧层厚度约为1.5 mm,差异显著;通过氧浓度线性分布、剖面拐点法得到氧气扩散边界厚度,上游监测点位的氧气扩散边界层厚度基本在1 mm,而下游监测点位的氧气扩散边界层厚度减少至0.2 mm。农田排水沟水体与底泥界面氧通量的测定,对于认识农田排水沟底泥的地球化学过程及水环境作用机理具有重要意义,可为农田排水沟水环境治理提供参考依据。 展开更多
关键词 农田排水沟 底泥 界面 扩散边界层 氧通量
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Two-thousand years of debates and practices of Yellow River training strategies 预览
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作者 Zhaoyin Wang Cheng Liu 《国际泥沙研究:英文版》 SCIE 2019年第1期73-83,共11页
Throughout the history of China,the Yellow River has been associated with flood disasters and changes in the course of its lower reaches because of sedimentation.From 602 B.C.to 1949 the river experienced 1593 levee b... Throughout the history of China,the Yellow River has been associated with flood disasters and changes in the course of its lower reaches because of sedimentation.From 602 B.C.to 1949 the river experienced 1593 levee bursts,flooding vast areas,and claiming millions of human lives.The river shifted its main course by avulsion 26 times with the apex around Zhengzhou,resulting in devastating calamities and numerous old channels.Training of the Yellow River has a history of more than 3000 yr.Levee construction has been the major strategy for flood control.Two extremely different strategies has been proposed and practiced in the past 2000 yr,i.e.the“wide river and depositing sediment”strategy and the“narrow river and scouring sediment”strategy.This paper analyzes the levee breaches and flood disasters in the past 2000 yr and compares the results of the two extremely different strategies.The“narrow river and scouring sediment”strategy has only short term effects on levee breach control and flood mitigation.The“wide river and depositing sediment”strategy can essentially mitigate flood disasters and reduce levee breaches for a long term period of time.The“wide river and depositing sediment”strategy has been used and no levee breach has occurred in the past 67 yr,which has been the only periods of more than 50 yr with no levee breaches in the history of the Yellow River since 700 A.D.Modern flood and sedimentation management methods have also been introduced,and the strategy of applying the“widen the river and enhance the levees”approach for the upper and lower reaches management is proposed. 展开更多
关键词 Yellow RIVER LEVEE breaches AVULSION Wide RIVER and depositing SEDIMENT STRATEGY Narrow RIVER and SCOURING SEDIMENT STRATEGY
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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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Sediment Transport Capacity Under the River-Tide Interaction in the Changjiang Estuary 预览
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作者 FENG Zhi-yong TAN Guang-ming XIA Jun-qiang 《中国海洋工程:英文版》 SCIE EI CSCD 2019年第2期207-218,共12页
Sediment transport capacity is a fundamental parameter in sediment transport theory and its accurate calculation is important from both theoretical and engineering viewpoints. The capacity of sediment transport has be... Sediment transport capacity is a fundamental parameter in sediment transport theory and its accurate calculation is important from both theoretical and engineering viewpoints. The capacity of sediment transport has been studied extensively by many researchers in the last decades. Nevertheless, the underlying mechanism behind sediment transport capacity in estuaries remains poorly understood. The current study aims to explore the impact of the river–tide interaction on sediment transport and establish a formula of sediment transport capacity under the river–tide interaction. The impact of the river–tide interaction on the hydrodynamics and sediment dynamics in the Changjiang Estuary was analyzed, a practical method for describing the variation in tide-runoff ratio was established, and a formula of sediment transport capacity considering the impact of river–tide interaction was proposed by introducing the tide-runoff ratio. The new method bridged the gap between two well-known sediment transport capacity methods by considering the variation in the index a for the gravitational term and overcomes the drawback of distinguishing flood/dry season or spring/ebb tide in the calculation of estuarine sediment transport. A large amount of flow and sediment data obtained from the Changjiang Estuary were collected to verify the proposed formula. The effect of salt-fresh water mixture and the morphological evolution on sediment transport capacity of the Changjiang Estuary were discussed. 展开更多
关键词 SEDIMENT transport capacity RIVER TIDE INTERACTION hydrodynamics and SEDIMENT dynamics Changjiang ESTUARY (Yangtze Estuary)
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Dynamic hydraulic jump and retrograde sedimentation in an open channel induced by sediment supply: experimental study and SPH simulation
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作者 ZHENG Xiao-gang CHEN Ri-dong +2 位作者 LUO Min KAZEMI Ehsan LIU Xing-nian 《山地科学学报:英文版》 SCIE CSCD 2019年第8期1913-1927,共15页
Mountainous torrents often carry large amounts of loose materials into the rivers, thus causing strong sediment transport. Experimentally it was found for the first time that when the intensive sediment motion occurs ... Mountainous torrents often carry large amounts of loose materials into the rivers, thus causing strong sediment transport. Experimentally it was found for the first time that when the intensive sediment motion occurs downstream over a gentle slope, the siltation of the riverbed is induced and the sediment particles can move upstream rapidly in the form of a retrograde sand wave, resulting in a higher water level along the river. To further study the complex mechanisms of this problem, a sediment mass model in the framework of the Smoothed Particle Hydrodynamics(SPH) method was presented to simulate the riverbed evolution, sediment particle motion, and the generation and development of dynamic hydraulic jump under the condition of sufficient sediment supply over a steep slope with varying angles. Because the sediment is not a continuous medium, the marker particle tracking approach was proposed to represent a piece of sediment with a marked sediment particle. The twophase SPH model realizes the interaction between the sediment and fluid by moving the bed boundary particles up and down, so it can reasonably treat the fluid-sediment interfaces with high CPU efficiency. The critical triggering condition of sediment motion, the propagation of the hydraulic jump and the initial siltation position were all systematically studied. The experimental and numerical results revealed the extra disastrous sediment effect in a mountainous flood. The findings will be useful references to the disaster prevention and mitigation in mountainous rivers. 展开更多
关键词 DYNAMIC hydraulic jump RETROGRADE SEDIMENTATION SEDIMENT supply Mountainous river Smoothed PARTICLE Hydrodynamics MARKED SEDIMENT PARTICLE
半封闭海湾内电厂建设水沙条件研究 预览
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作者 李文丹 郑玮 +1 位作者 韩志远 解鸣晓 《水道港口》 2019年第4期404-410,共7页
文章通过现场实测的波浪、潮位、潮流、含沙量、底质等资料分析,岸滩演变分析以及沿岸输沙数值模拟和波浪、潮流、泥沙数学模型计算,对福建省莆田市兴化湾西侧海域建设某电厂的水动力泥沙条件进行了研究论证。主要研究成果表明:(1)工程... 文章通过现场实测的波浪、潮位、潮流、含沙量、底质等资料分析,岸滩演变分析以及沿岸输沙数值模拟和波浪、潮流、泥沙数学模型计算,对福建省莆田市兴化湾西侧海域建设某电厂的水动力泥沙条件进行了研究论证。主要研究成果表明:(1)工程位于兴化湾口石城南侧岬湾内,东南面临开敞海域,潮差大、湾内潮流较弱、水体含沙量低、泥沙来源有限。(2)工程海域海床长期处于稳定状态,且沿岸输沙微弱。(3)电厂取水口位于岬角南侧-7.5m等深线附近水域,取水明渠内泥沙淤积强度较小。综上,工程海域具有良好的建厂条件。 展开更多
关键词 潮流 泥沙 电厂 沿岸输沙 莆田
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疏勒河流域泥沙分布规律及水沙关系研究
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作者 严宇红 黄维东 +1 位作者 吴锦奎 黄晨璐 《干旱区地理》 CSCD 北大核心 2019年第1期47-55,共9页
泥沙是影响河流健康和水环境的重要因素之一,受气候变化和人类活动的影响,流域水文要素和下垫面条件发生了较大变化,尤其是实施大规模的水土保持措施后,部分河流的泥沙含量大幅减少,但在河西内陆河流域发源于祁连山西端的疏勒河流域,受... 泥沙是影响河流健康和水环境的重要因素之一,受气候变化和人类活动的影响,流域水文要素和下垫面条件发生了较大变化,尤其是实施大规模的水土保持措施后,部分河流的泥沙含量大幅减少,但在河西内陆河流域发源于祁连山西端的疏勒河流域,受降水条件和人类活动的影响,河流泥沙呈增加趋势。应用疏勒河流域实测长系列水文资料,采用水文统计法、差积曲线法、趋势检验法、突变检验法、非线性复相关模型法等方法,分析了流域泥沙时空分布规律及水沙关系,结果表明:疏勒河干流昌马堡站年输沙量为333. 5×10^4t,至下游潘家庄站减少到223. 5×10^4t;党河党城湾站年输沙量为76. 56×10^4t,至下游沙枣园站增加到121. 3×10^4t;疏勒河干流输沙量主要集中在汛期7~8月,占全年的81. 9%~84. 0%,党河流域输沙量主要集中在4~8月,占全年的92. 3%;流域泥沙变化总体呈增加趋势,突变点1998年以后,年输沙量增加了86. 3%~148. 2%。建立了潘家庄站降水-泥沙、径流-泥沙以及年输沙量-年径流量-年最大洪峰流量关系模型,相关系数达到0. 717~0. 858。流域出山口以上对泥沙的影响因素主要是降水,出山口以下主要是修建水库、水电站、引水工程、河道采砂等人类活动影响。随着国家对内陆河流域祁连山和河西走廊的日益关注,以及全国河长制的推行,河流生态健康已经提上日程,研究疏勒河流域泥沙分布规律及水沙关系,对国家实施西部生态安全战略、区域生态环境修复治理、水资源可持续利用等具有重要意义。 展开更多
关键词 泥沙 分布规律 趋势变化 水沙关系 疏勒河
乐安河水体重金属出入河通量探究 预览
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作者 汪艳芳 武心嘉 +2 位作者 戚晓明 白夏 杨兰 《环境监测管理与技术》 CSCD 2019年第4期60-63,共4页
在分析乐安河沿程水质的基础上,将乐安河全年按丰水期、平水期、枯水期分别统计进出水量、总重金属及溶解态重金属年出入河通量。结果表明:乐安河总重金属质量浓度及溶解态重金属质量浓度呈先上升后下降趋势,出水水质仍能达到Ⅲ类水质标... 在分析乐安河沿程水质的基础上,将乐安河全年按丰水期、平水期、枯水期分别统计进出水量、总重金属及溶解态重金属年出入河通量。结果表明:乐安河总重金属质量浓度及溶解态重金属质量浓度呈先上升后下降趋势,出水水质仍能达到Ⅲ类水质标准;2016年乐安河内新增Cu、Zn、Pb质量分别为36.968t、51.39t、0.288t;乐安河内每年可新增重金属量已逐年减少,大量重金属元素将最终排入鄱阳湖内。 展开更多
关键词 重金属 通量 水质 沉积物 乐安河
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Relationship between heavy metals and dissolved organic matter released from sediment by bioturbation/bioirrigation
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作者 Yi He Bin Men +3 位作者 Xiaofang Yang Yaxuan Li Hui Xu Dongsheng Wang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第1期216-223,共8页
Organic matter (OM)is an important component of sediment.Bioturbation/bioirrigation can remobilize OM and heavy metals that were previously buried in the sediment.The remobilization of buried organic matter,thallium (... Organic matter (OM)is an important component of sediment.Bioturbation/bioirrigation can remobilize OM and heavy metals that were previously buried in the sediment.The remobilization of buried organic matter,thallium (Tl),cadmium (Cd),copper (Cu)and zinc (Zn)from sediment was studied in a laboratory experiment with three organisms:tubificid, chironomid larvae and loach.Results showed that bioturbation/bioirrigation promoted the release of dissolved,organic matter (DOM)and dissolved Tl,Cd,Cu and Zn,but only dissolved Zn concentrations decreased with exposure time in overlying water.The presence of organisms altered'the compositions of DOM released from sediment, considerably increasing the percentage of fulvic acid-like materials (FA)and humic acidlike materials (HA).In addition,bioturbation/bioirrigation accelerated the growth and reproduction of bacteria to enhance the proportion of soluble microbial byproduct-like materials (SMP).The DOM was divided into five regions in the three-dimensional excitation emission matrix (3D-EEM),and each part had different correlation with the dissolved heavy metal concentrations.Dissolved Cu had the best correlation with each of the DOM compositions,indicating that Cu in the sediment was in the organic-bound form. Furthermore,the organism type and heavy metal characteristics both played a role in influencing the remobilization of heavy metal. 展开更多
关键词 Bioturb ation/bioirrigation HEAVY metal SEDIMENT DOM
An interpretation of wave refraction and its influence on foreshore sediment distribution 预览
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作者 Vincent Jayaraj Joevivek Nainarpandian Chandrasekar +2 位作者 Ramakrishnan Jayangondaperumal Vikram Chandra Thakur Krishnan Shree Purniema 《海洋学报:英文版》 SCIE CAS CSCD 2019年第5期151-160,共10页
To analyze the grain size and depositional environment of the foreshore sediments,a study was undertaken on wave refraction along the wide sandy beaches of central Tamil Nadu coast.The nearshore waves approach the coa... To analyze the grain size and depositional environment of the foreshore sediments,a study was undertaken on wave refraction along the wide sandy beaches of central Tamil Nadu coast.The nearshore waves approach the coast at 45°during the northeast(NE)monsoon,at 135°during the southwest(SW)monsoon and at 90°during the non-monsoon or fair-weather period with a predominant wave period of 8 and 10 s.A computer based wave refraction pattern is constructed to evaluate the trajectories of shoreward propagating waves along the coast in different seasons.The convergent wave rays during NE monsoon,leads to high energy wave condition which conveys a continuous erosion at foreshore region while divergent and inept condition of rays during the SW and non-monsoon,leads to moderate and less energy waves that clearly demarcates the rebuilt beach sediments through littoral sediment transport.The role of wave refraction in foreshore deposits was understood by grain size and depositional environment analysis.The presence of fine grains with the mixed population,during the NE monsoon reveals that the high energy wave condition and sediments were derived from beach and river environment.Conversely,the presence of medium grains with uniform population,during SW and non-monsoon attested less turbulence and sediments were derived from prolong propagation of onshore-offshore wave process.These upshots are apparently correlated with the in situ beach condition.On the whole,from this study it is understood that beaches underwent erosion during the NE monsoon and restored its original condition during the SW and non-monsoon seasons that exposed the stability of the beach and nearshore condition. 展开更多
关键词 foreshore GRAIN size wave REFRACTION SEDIMENT transport BEACH INDIA
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一种批量连续提取沉积物中无机磷的微量测定方法
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作者 袁聪 华祖林 +3 位作者 丁珏 沈健 聂永平 倪效欣 《分析试验室》 CAS CSCD 北大核心 2019年第5期548-552,共5页
发展了一种批量连续提取沉积物中反应性无机磷的微量测定方法。以2 mL规格的圆底旋盖离心管为提取容器,对沉积物中的弱吸附态磷、铁锰结合态磷、铝结合态磷和钙结合态磷进行提取。利用酶标仪自行建立磷钼蓝微量比色方法测定上清液中磷... 发展了一种批量连续提取沉积物中反应性无机磷的微量测定方法。以2 mL规格的圆底旋盖离心管为提取容器,对沉积物中的弱吸附态磷、铁锰结合态磷、铝结合态磷和钙结合态磷进行提取。利用酶标仪自行建立磷钼蓝微量比色方法测定上清液中磷的浓度,其检出限为3μg/L,RSD在6%以内。同时,使用微量测定法对大沙河湿地、骆马湖等5个研究区沉积物中各形态无机磷的含量进行检测,精密度较好。运用Kruskal-Wallis非参数检验法与常规方法测得的结果进行比较,两种方法无显著性差异。方法为湖泊沉积物中磷形态的获取提供了新的路径。 展开更多
关键词 沉积物 连续提取 无机磷 磷形态 微量比色 批量
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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