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1.
The delta evolution and erosion process of the abandoned Yellow River Delta (AYRD) have been extensively studied. However, the variation of sediment at a large littoral scale along the north coast of Jiangsu is less understood. In this study, the data of surface sediment samples obtained in the littoral area of the Yellow River Delta in 2006 and 2012 is used to study the sediment variability and sediment transport trends by using the geostatistics analysis tool and the grain size trend analysis model. In order to ensure the applicability of the model, the geostatistics method is used to determine the characteristic distance (Dc) with the average range value (Ao) of grain size parameter. Filtering method (removing data that not at a sampling station) is used to improve accuracy of data selection. The results show that sedimentary spatial correlation in Lianyun Port area and southern part of the abandoned Yellow River Delta (AS) is better than that in the northern part of the abandoned Yellow River Delta (AN). Sediment in the area is found to be anisotropy at the northeast-southeast direction. The grain size trend analysis reveals that the sediment trend is towards bayhead and southerly in the Haizhou Bay, southeasterly along the shoreline in the south Lianyun Port, northwesterly in AN and easterly-southeasterly in AS respectively. The investigation of possible relationships between Dc, Ao, sediment transport and delta evolution shows a close link between Dc and Ao of one sediment combination. It is also found that sediment transport trends could reasonably represent the delta evolution to a certain degree. 相似文献
2.
黄海粘土沉积物的来源与分布 总被引：4，自引：0，他引：4
本文根据区域自然地理原理,划分黄海粘土沉积物的补给区,在粘土矿物鉴定的基础上,用法方程定量探明黄海粘土沉积物的来源与分布,绘出黄海粘土沉积物分布图。图示:黄海来源于长江的粘土沉积物的分布面积,占其总面积的56.5%,来源于黄河的占43.5%。粘土沉积物的分布同洋流、海流的分布相吻合。 相似文献
3.
近60年黄河水沙变化及其对三角洲沉积的影响 总被引：1，自引：1，他引：0
In order to find out the variation process of water-sediment and its effect on the Yellow River Delta, the water discharge and sediment load at Lijin from 1950 to 2007 and the decrease of water discharge and sediment load in the Yellow River Basin caused by human disturbances were analyzed by means of statistics. It was shown that the water discharge and sediment load into the sea were decreasing from 1950 to 2007 with serious fluctuation. The human activities were the main cause for decrease of water discharge and sediment load into the sea. From 1950 to 2005, the average annual reduction of water discharge and sediment load by means of water-soil conservation practices were 2.02×109 m3 and 3.41×108 t respectively, and the average annual volume by water abstraction for industry and agriculture were 2.52×1010 m3 and 2.42×108 t respectively. The average sediment trapped by Sanmenxia Reservoir was 1.45×108 t from 1960 to 2007, and the average sediment retention of Xiaolangdi Reservoir was 2.398×108 t from 1997 to 2007. Compared to the data records at Huanyuankou, the water discharge and sediment load into the sea decreased with siltation in the lower reaches and increased with scouring in the lower reaches. The coastline near river mouth extended and the delta area increased when the ratio of accumulative sediment load and accumulative water discharge into the sea (SSCT) is 25.4–26.0 kg/m3 in different time periods. However, the sharp decrease of water discharge and sediment load into the sea in recent years, especially the Yellow River into the sea at Qing 8, the entire Yellow River Delta has turned into erosion from siltation, and the time for a reversal of the state was about 1997. 相似文献
4.
Changxing Shi David Dian Zhang 《Geografiska Annaler: Series A, Physical Geography》2005,87(3):461-471
This study investigates the sediment fluxes through the Yellow River sediment routing system, which are among the largest in the world, by constructing a sediment budget of the system over the period from 1855 to 1968. The framework of the sediment budget includes four functional units with the upper and middle reaches of the river as the sediment source and its lower reaches, its delta, and the deep sea as the sediment sinks. Sediment yield from the source and amounts of deposition in the lower Yellow River and the modern Yellow River delta were estimated for completing the sediment budget. The sediment budget produced for the period from 1855 to 1968 was characterized by a sediment input of 1.837 × 1011 tonnes and a distribution of the sediment between the lower Yellow River, the delta, and the deep sea of 64%, 33%, and 3%, respectively. The details of the sediment budget show that the importance of sedimentation in the lower Yellow River changed greatly with variations in the condition of the dykes and other human activities. A comparison of the sediment budgets of the delta for different timescales shows that the proportion of sediment dispersed to the deep sea decreases as the timescale over which the sediment fluxes are investigated increases. 相似文献
5.
黄河口泥沙淤积估算问题和方法——以钓口河亚三角洲为例 总被引：11，自引：1，他引：10
以往在黄河三角洲沉积量的估算中,对沉积物干容重和计算边界等问题不够重视,导致计算结果存在明显出入。本项研究通过广泛收集资料和大量采样分析得到了多种沉积环境下沉积物干容重的计算模型,结合三角洲沉积结构分析和利用地形测量数据,计算了黄河口钓口河流路时期亚三角洲不同时期的沉积量。其中1965年至1974年间钓口河亚三角洲前缘坡脚以内的总淤积量为71.0亿t。其平均干容重为1.36g/cm3。这一干容重用于估算其它亚三角洲沉积量不会造成明显误差。认为忽略三角洲下松软沉积层的压实沉降、三角洲平原相和前缘相中粘性土与非粘性土干容重的差别以及来沙量的测量误差对计算结果影响较小。 相似文献
6.
在全新世时间尺度内,沉积记录主要受控于沉积物供给、输运和堆积过程等因素。对废黄河沉积记录的深入分析可以反演黄河南流夺淮过程中沉积物的“源”-“汇”关系。基于废黄河故道沉积记录中重矿物和地球化学元素特征,并结合与现代黄河沉积物的对比,揭示废黄河沉积记录中物质来源的信息。结果表明,废黄河故道沉积物中重矿物平均含量为0.19%,种类多达15余种,以稳定矿物为主,不同矿物的时空变化差异较大。废黄河故道泥质和砂质沉积物中,地球化学元素表现出明显的时空变化规律,随深度递增元素含量可分为降低、稳定和增加趋势。对比现代黄河沉积物,发现废黄河故道沉积物中稳定和极稳定矿物相对含量较高,泥质沉积物中更多地富集Zn,Ni,Al,Ba,Cu,Li,K等元素。这一差异性反映出其它不同河流物质补给而产生的影响,淮河沉积物中重矿物和地球化学元素的研究为该论断提供了佐证。 相似文献
7.
Five diagnostic experiments with a 3D baroclinic hydrodynamic and sediment transport model ECOMSED in couple with the third generation wave model SWAN and the Grant–Madsen bottom boundary layer model driven by the monthly sediment load of the Yellow River, were conducted to separately diagnose effects of different hydrodynamic factors on transport of suspended sediment discharged from the Yellow River in the Bohai Sea. Both transport and spatio-temporal distribution of suspended sediment concentration in the Bohai Sea were numerially simulated. It could be concluded that suspended sediment discharged from the Yellow River cannot be delivered in long distance under the condition of tidal current. Almost all of sediments from the Yellow River are deposited outside the delta under the condition of wind-driven current, and only very small of them are transported faraway. On the basis of wind forcing, sediments from the Yellow River are mainly transported north-northwestward, and others which are first delivered to the Laizhou Bay are continuously moved northward. An obvious 3D structure characteristic of sediment transport is produced in the wind-driven and tide-induced residual circulation condition. Transport patterns at all layers are generally consistent with circulation structure, but there is apparent deviation between the depth-averaged sediment flux and the circulation structure. The phase of temporal variation of sediment concentration is consistent with that of the bottom shear stress, both of which are proved to have a ten-day cycle in wave and current condition. 相似文献
8.
废黄河三角洲的演变* 总被引：20，自引：1，他引：19
本文主要根据历史文献,论述1194～1855年的古黄河口泥沙堆积形式、速率及其沉积特点,并探讨了废黄河三角洲形成机理和类型,以及尾闾变迁对下游河道的影响。认为在黄河南流夺准入黄海过程中,河口和三角洲发育具有明显的阶段性;前、后两期形成不同类型的三角洲,前期为径流一潮汐型,后期转化为径流一波浪型;后期河口迅速延伸,河口基准面相对抬升所引起的溯源淤积可达河南境内。 相似文献
9.
黄河三角洲造陆过程中的陆域水沙临界条件研究 总被引：26，自引：5，他引：26
黄河三角洲发育是河口区河流动力及陆域物质通量与海洋动力及海域物质通量相互作用的产物 ,三角洲造陆速率取决于上述两方面的对比关系。当上述两方面处于平衡时 ,三角洲造陆处于临界状态 ,即净造陆速率为零 ,与之相联系的入海泥沙量和径流量可视为黄河三角洲造陆过程的临界水沙条件。运用经验统计方法估算出 :当入海年沙量Qs为 2 78亿t/a、入海年水量Qw为 76 7亿m3时 ,或者当关系式 3 1934Qs+ 0 0 85 6Qw=17 94得到满足时 ,黄河三角洲造陆过程处于临界平衡状态。在黄河流域的环境管理中 ,应将上述两项临界值作为约束条件。黄河流域生态用水量的内涵应予以扩展 ,维持三角洲造陆平衡所必须的入海径流量 ,应作为黄河流域的生态用水量。 相似文献
10.
Five diagnostic experiments with a 3D baroclinic hydrodynamic and sediment transport model ECOMSED in couple with the third
generation wave model SWAN and the Grant-Madsen bottom boundary layer model driven by the monthly sediment load of the Yellow
River, were conducted to separately diagnose effects of different hydrodynamic factors on transport of suspended sediment
discharged from the Yellow River in the Bohai Sea. Both transport and spatio-temporal distribution of suspended sediment concentration
in the Bohai Sea were numerially simulated. It could be concluded that suspended sediment discharged from the Yellow River
cannot be delivered in long distance under the condition of tidal current. Almost all of sediments from the Yellow River are
deposited outside the delta under the condition of wind-driven current, and only very small of them are transported faraway.
On the basis of wind forcing, sediments from the Yellow River are mainly transported north-northwestward, and others which
are first delivered to the Laizhou Bay are continuously moved northward. An obvious 3D structure characteristic of sediment
transport is produced in the wind-driven and tide-induced residual circulation condition. Transport patterns at all layers
are generally consistent with circulation structure, but there is apparent deviation between the depth-averaged sediment flux
and the circulation structure. The phase of temporal variation of sediment concentration is consistent with that of the bottom
shear stress, both of which are proved to have a ten-day cycle in wave and current condition. 相似文献
11.
黄河口不同粒度泥沙沉积与扩散分析 总被引：1，自引：0，他引：1
本文采集和收集大量黄河三角洲沉积物剖面和钻孔泥沙粒度资料以及黄河口来沙粒度组成数据,定量研究了黄河口泥沙的沉积与扩散特征.结果 显示黄河口来沙以粉砂为主,黏土次之,砂最少,年均中值粒径无长期变化趋势.黄河三角洲平原相泥沙与来沙的黏土、粉砂和砂含量无显著差异;前缘相泥沙比来沙的黏土含量较低,砂含量较高;前三角洲相泥沙比来... 相似文献
12.
7000年来渤海西岸、南岸海岸线变迁 总被引：3，自引：0，他引：3
渤海西岸、南岸从全新世海侵边界至现在海岸线之间的海岸低地是7 000 a B.P.以来多个三角洲进积的结果.由于黄河人海泥沙数量巨大,导致下游河道频繁摆动,活动三角洲(超级叶瓣)位置多次变迁.滦河三角洲活动叶瓣位置也多次变迁.海岸线变迁受三角洲演化控制:活动期推进、废弃初期后退和之后的长期稳定,表现分片突进模式.整体来说研究区各时期海岸线表现出局部突出、局部内凹特点.在这样的三角洲群地区不可能出现近乎匀速的平推式海岸变迁. 相似文献
13.
In order to find out the variation process of water-sediment and its effect on the Yellow River Delta, the water discharge and sediment load at Lijin from 1950 to 2007 and the decrease of water discharge and sediment load in the Yellow River Basin caused by human disturbances were analyzed by means of statistics. It was shown that the water discharge and sediment load into the sea were decreasing from 1950 to 2007 with serious fluctuation. The human activities were the main cause for decrease of water discharge and sediment load into the sea. From 1950 to 2005, the average annual reduction of water discharge and sediment load by means of water-soil conservation practices were 2.02×109 m3 and 3.41×108 t respectively, and the average annual volume by water abstraction for industry and agriculture were 2.52×1010 m3 and 2.42×108 t respectively. The average sediment trapped by Sanmenxia Reservoir was 1.45×108 t from 1960 to 2007, and the average sediment retention of Xiaolangdi Reservoir was 2.398×108 t from 1997 to 2007. Compared to the data records at Huanyuankou, the water discharge and sediment load into the sea decreased with siltation in the lower reaches and increased with scouring in the lower reaches. The coastline near river mouth extended and the delta area increased when the ratio of accumulative sediment load and accumulative water discharge into the sea (SSCT) is 25.4–26.0 kg/m3 in different time periods. However, the sharp decrease of water discharge and sediment load into the sea in recent years, especially the Yellow River into the sea at Qing 8, the entire Yellow River Delta has turned into erosion from siltation, and the time for a reversal of the state was about 1997. 相似文献
14.
Based on sediment and discharge flux data for the Yellow River, realistic forcing fields and bathymetry of the Bohai Sea,
a suspended sediment transport module is driven by a wave-current coupled model to research seasonal variations and mechanisms
of suspended load transport to the Bohai Sea. It could be concluded that surface sediment concentration indicates a distinct
spatial distribution characteristic that varies seasonally in the Bohai Sea. Sediment concentration is rather high near the
Yellow River estuary, seasonal variations of which are controlled by quantity of sediment from the Yellow River, suspended
sediment concentration reaches its maximum during summer and fall. Furthermore, sediment concentration decreases rapidly in
other seas far from the Yellow River estuary and maintains a very low level in the center of the Bohai Sea, and is dominated
by seasonal variations of climatology wind field in the Bohai Sea. Only a small amount of sediments imported from the Yellow
River are delivered northwestward to the southern coast of the Bohai Bay. Majority of sediments are transported southeastward
to the Laizhou Bay, where sediments are continuously delivered into the center of the Bohai Sea in a northeastward direction,
and part of them are transported eastward alongshore through the Bohai Strait. 69% of sediments from the Yellow River are
deposited near the river delta, 31% conveyed seaward, within which, 4% exported to the northern Yellow Sea through the Bohai
Strait. Wind wave is the most essential contributor to seasonal variations of sediment concentration in the Bohai Sea, and
the contribution of tidal currents is also significant in shallow waters when wind speed is low. 相似文献
15.
Based on sediment and discharge flux data for the Yellow River, realistic forcing fields and bathymetry of the Bohai Sea, a suspended sediment transport module is driven by a wave-current coupled model to research seasonal variations and mechanisms of suspended load transport to the Bohai Sea. It could be concluded that surface sediment concentration indicates a distinct spatial distribution characteristic that varies seasonally in the Bohai Sea. Sediment concentration is rather high near the Yellow River estuary, seasonal variations of which are controlled by quantity of sediment from the Yellow River, suspended sediment concentration reaches its maximum during summer and fall. Furthermore, sediment concentration decreases rapidly in other seas far from the Yellow River estuary and maintains a very low level in the center of the Bohai Sea, and is dominated by seasonal variations of climatology wind field in the Bohai Sea. Only a small amount of sediments imported from the Yellow River are delivered northwestward to the southern coast of the Bohai Bay. Majority of sediments are transported southeastward to the Laizhou Bay, where sediments are continuously delivered into the center of the Bohai Sea in a northeastward direction, and part of them are transported eastward alongshore through the Bohai Strait. 69% of sediments from the Yellow River are deposited near the river delta, 31% conveyed seaward, within which, 4% exported to the northern Yellow Sea through the Bohai Strait. Wind wave is the most essential contributor to seasonal variations of sediment concentration in the Bohai Sea, and the contribution of tidal currents is also significant in shallow waters when wind speed is low. 相似文献
16.
Andrew G. Warne Robert H. Meade William A. White Edgar H. Guevara James Gibeaut Rebecca C. Smyth Andres Aslan Thomas Tremblay 《Geomorphology》2002,44(3-4)
Interacting river discharge, tidal oscillation, and tropical rainfall across the 22,000 km2 Orinoco delta plain support diverse fresh and brackish water ecosystems. To develop environmental baseline information for this largely unpopulated region, we evaluate major coastal plain, shallow marine, and river systems of northeastern South America, which serves to identify principal sources and controls of water and sediment flow into, through, and out of the Orinoco Delta.The regional analysis includes a summary of the geology, hydrodynamics, sediment dynamics, and geomorphic characteristics of the Orinoco drainage basin, river, and delta system. Because the Amazon River is a major source of sediment deposited along the Orinoco coast, we summarize Amazon water and sediment input to the northeastern South American littoral zone. We investigate sediment dynamics and geomorphology of the Guiana coast, where marine processes and Holocene history are similar to the Orinoco coast.Major factors controlling Orinoco Delta water and sediment dynamics include the pronounced annual flood discharge; the uneven distribution of water and sediment discharge across the delta plain; discharge of large volumes of water with low sediment concentrations through the Río Grande and Araguao distributaries; water and sediment dynamics associated with the Guayana littoral current along the northeastern South American coast; inflow of large volumes of Amazon sediment to the Orinoco coast; development of a fresh water plume seaward of Boca Grande; disruption of the Guayana Current by Trinidad, Boca de Serpientes, and Gulf of Paria; and the constriction at Boca de Serpientes. 相似文献
17.
基于遥感和GIS的江苏省海岸线时空变化 总被引：5，自引：0，他引：5
以江苏省海岸1973-2012年的Landsat MSS/TM/ETM+遥感影像为数据源,利用遥感和GIS技术,对江苏省海岸线的时空变化进行分析。结果表明：显著侵蚀岸段以废黄河口为中心,北至新淮河口,南至双洋港,长度约79.05 km,占研究区岸线总长度的8%;淤涨岸段以弶港为中心,北至运粮河口,南至新中港,长约715.50 km,占72%;其它部分稳定岸段与淤涨岸段相间存在。最大侵蚀速率为-23.37±11.92 m/a,位于废黄河口南侧;最大淤涨速率为445.37±66.80 m/a,位于射阳河口南侧。围垦是江苏省岸线变化的主要因素。总的来看,1973年以来40年间共围垦1912.4 km2,1980年前后出现了一个围垦高峰,之后围垦强度明显减弱且进入休养期,90年代以后围垦又普遍加强。 相似文献
18.
The Yellow River is unique among the major rivers of the world because of its extremely heavy sediment load in relation to its small discharge. The Yellow River has changed courses numerous times during the past 5000 to 6000 years. With its large sediment load, most of which comes from the Loess Plateau of central China, the river has created a number of deltas along the coast of northern China. The abandoned deltas are eroding, whereas the present delta being formed in Bohai Bay is growing rapidly. Human activity, including extensive agriculture, heavy water consumption, the use of river-control structures, and war, has been responsible for many of the changes occurring in the Yellow River and its delta. [Key words: hydrology, loess, floods, Yellow River, Bohai Bay, China.] 相似文献
19.
黄河下游泥沙输移数值模拟 总被引：2，自引：0，他引：2
本文从数学模型入手,探讨黄河下游在多年平均来水来沙条件下,泥沙输移与泥沙淤积的特性,得出黄河下游泥沙沿程淤积分布不均匀主要是由于粗沙、中沙沿程淤积不均匀造成的,如果使来沙减少42.6%,黄河下游可望达到冲淤平衡. 相似文献
20.
黄河三角洲沉积物的自然固结压实过程及其影响 总被引：15，自引：2，他引：13
对黄河三角洲及下伏沉积物的压实量和压实过程及其引起的地面沉降进行了分析研究。分析认为,在厚度为15 m的新淤积的黄河三角洲沉积重压下,前三角洲粘土和下伏海相粘土总固结量可达约1.35 m,海湾或烂泥湾及前三角洲和海相粘土总压缩量为1.48 m。这些粘土层在亚三角洲建设时期就开始受压固结,但是在亚三角洲废弃后,仍要经过几十年自然固结才会基本完成。除去前10年的固结量,前三角洲粘土与下伏海相粘土叠加形成的14 m厚粘土在随后的27年内可能会压缩50 cm;而海湾或烂泥湾及前三角洲和海相粘土叠加成的20 m厚粘土在50年内可能会压缩86 cm,两者的年平均压缩速率都超过17 mm/a。固结量和速率与上负沉积物重量成正比,而亚三角洲沉积厚度从沉积中心向外围逐渐减少,所以下伏粘土固结量和速率也向周围逐渐降低。但从亚三角洲沉积厚度分布情况看,在大范围内,下伏粘土固结引起的地面沉降在几十年内都将比较明显,从而可能加重三角洲地区风暴潮和海岸侵蚀灾害,降低已有灾害防治工程的作用。 相似文献