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1.
The Huanghe (Yellow) River, with annual sediment discharge about 11 ×108tons, contributes about 17% of the fluvial sediment discharge of world's 21 major rivers to the ocean because its middle reaches flow across the great Loess Plateau of China. Sediment discharge of the Huanghe River has a widespread and profound effect on sedimentation of the sea. The remarkable shift of its outlet in 1128-1855 A.D. to the South Yellow Sea formed a large subaqueous delta and provided the substrate for an extensive submarine ridge field.The shift of its outlet in the modern delta every 10 years is the main reason why with an extremely heavy sediment input and a micro- tidal environment, the Huanghe River has not succeeded in building a birdfoot delta like the Mississippi. The Huanghe River has consistently brought heavy sediment input to sea at least since 0.7 myr.B.P. Paleochannels, paleosols, cheniers and fossils on the sea bottom indicate that the Yellow Sea was exposed during the late Quaternary glacial low-sea l 相似文献
2.
Global carbon cycling is a significant factor that controls climate change.The centennial-scale variations in total organic carbon(TOC)contents and its sources in marginal sea sediments may reflect the influence of human activities on global climate change.In this study,two fine-grained sediment cores from the Yellow Sea Cold Water Mass of the South Yellow Sea were used to systematically determine TOC contents and stable carbon isotope ratios.These results were combined with previous data of black carbon and (210)~Pb dating from which we reconstructed the centennial-scale initial sequences of TOC,terrigenous TOC(TOC_(ter))and marine autogenous TOC(TOC_(mar))after selecting suitable models to correct the measured TOC(TOC_(cor)).These sequences showed that the TOC_(ter) decreased with time in the both cores while the TOC_(mar) increased,particularly the rapid growth in core H43 since the late 1960s.According to the correlation between the Huanghe(Yellow)River discharge and the TOC_(cor),TOC_(ter),or TOC_(mar),we found that the TOC_(ter) in the two cores mainly derived from the Huanghe River and was transported by it,and that higher Huanghe River discharge could strengthen the decomposition of TOC_(mar).The newly obtained initial TOC sequences provide important insights into the interaction between human activities and natural processes. 相似文献
3.
There widely occur stretches of permafrost at more than 3,800-4,200 meters above sea level in the source area of the Huanghe (Yellow) River. The periglacial geomorphology develops quite well, including frozen disintegration geomorphology, freezing and thawing geomorphology in cold environments, periglacial dune, buried ices and fossil periglacial phenomena. In light of the relation between stratigraphy and periglacial phenomena, three periglacial periods can be divided, which are the Middle Pleistocene periglacial period, the Late Pleistocene periglacial period and modern periglacial period. 相似文献
4.
Paleo-fluvial sedimentation on the outer shelf of the East China Sea during the last glacial maximum 总被引：1，自引：0，他引：1
Evidence from lithology, foraminiferal assemblages, and high-resolution X-ray fluorescence scanning data of core SFK-1 indicates tidally influenced paleo-fluvial sedimentation during the last glacial maximum (LGM) on the outer shelf of the East China Sea. The paleo-fluvial deposits consist of river channel facies and estuarine incised-valley-filling facies. Different reflections on the seismic profile across core SFK-1 suggest that the river channels shifted and overlapped. River channel deposition formed early in the LGM when sea level fell and the estuary extended to the outer shelf. Channel sediments are yellowish-brown in color and rich in foraminifera and shell fragments owing to the strong tidal influence. Following the LGM, the paleo-river mouth retreated and regressive deposition of estuarine and incised-valley-filling facies with an erosion base occurred. The river channel facies and estuarine incised-valley-filling facies have clearly different sedimentary characteristics and provenances. The depositional environment of the paleoriver system on the wide shelf was reconstructed from the foraminiferal assemblages, CaCO3 content and Ca/Ti ratio. The main results of this study provide further substantial constraints on the recognition of late Quaternary stratigraphy and land-sea interactions on the ECS shelf. 相似文献
5.
本文通过钱塘江深切谷的论述对末次冰期深切谷的恢复主要依据下列证据进行：（1）谷底为侵蚀不整合面，为末次冰期海平面下降，河流侵蚀切割所致；（2）谷内为异常厚的河流沉积物所充填，是冰后期海平面上升时形成，其中河漫滩沉积年代约14000～7500a以前；（3）深切谷之上被海相地层覆盖。超浅层生物气田分布在深切谷内，当今河流及全新世晚期河口湾与末次冰期深切谷既有区别又有继承性，其流域是浅层生物气藏分布的有利地段。 相似文献
6.
In an estuary,tidal,wave and other marine powers interact with the coast in different ways and affect estuary morphology as well as its evolution.In the Huanghe(Yellow) River estuaries and nearby delta,there are many small sediment-affected estuaries with a unique morphology,such as the Xiaoqing River estuary.In this study,we investigated the special evolution and genetic mechanism of the Xiaoqing River estuary by analyzing graphic and image data with a numerical simulation method.The results show that NE and NE-E tide waves are the main driving force for sandbar formation.Sediment shoals have originated from huge amounts of sediment from the Huanghe River,with consequent deposition at the Xiaoqing River mouth.The lateral suspended sediments beyond the river mouth move landward.Siltation takes place on the northern shoreline near the river mouth whereas erosion occurs in the south.The deposits come mainly from scouring of the shallow seabed on the northern side of the estuary.Storm surges speed up deposition in the estuary.Development of the sediment shoals has occurred in two steps involving the processes of growth and further southward extension.Although the southward shift increases the river curvature and length,the general eastward orientation of the estuary is unlikely to change.Processes on the adjacent shorelines do not affect the development of the sediment shoals.The study presents a morphodynamic evolutionary model for the Xiaoqing River estuary,with a long-term series cycle,within which a relatively short cycle occurs. 相似文献
7.
One of the most important factors controlling the morphology of the modern Huanghe(Yellow) River delta is consolidation settlement, which is impacted by fast deposition, high water content, and low density of seafloor sediment. Consolidation settlement of the Huanghe River subaqueous delta was studied based on field data, laboratory experiments on 12 drill holes, and the one-dimensional consolidation theory. Results show that vertical sediment characteristics varied greatly in the rapidly forming sedimentary bodies of the modern Huanghe River subaqueous delta. Sediments in the upper parts of drill holes were coarser than those in the deeper parts, and other physical and mechanical properties changed accordingly. On the basis of the one-dimensional consolidation theory and drilling depth, the final consolidation settlement of drill holes was between 0.6 m and 2.8 m, and the mean settlement of unit depth was at 1.5–3.5 cm/m. It takes about 15–20 years for the consolidation degree to reach 90% and the average sedimentation rate within the overlying 50 m strata was at 5 cm/a to 12 cm/a. This study helps to forecast the final consolidation settlement and settlement rate of the modern Huanghe River subaqueous delta, which provides key geotechnical information for marine engineers. 相似文献
8.
Investigations and studies for years all demonstrated that there is a patch of fine-grained mud in the central area of the
South Yellow Sea. However, scientists have different opinions on its material source, genesis, and sedimentation intensity.
Some believe that the materials come from the Huanghe River, some think that the mud area represents the depocentre of the
South Yellow Sea, and some consider it as “relict mud”. The authors' geochemical study reveals that the mud is multi-sourced,
yet the material supply is not ample, and that a little amount of fine-grained suspended materials deposited slowly under
the dynamic action of a cyclonic gyre formed the modern muddy sediment, which is named “multi-source modern mud”.
Project supported by the National Natural Science Foundation of China, contribution No. 1646 from the Institute of Oceanology,
Academia Sinica. 相似文献
9.
Based on the data from gauging stations,the changes in water discharge and sediment load of the Huanghe (Yellow)River were analyzed by using the empirical mode decomposition(EMD)method.The results show that the periodic oscillation of water discharge and sediment load of the Huanghe River occurs at the interannual,decadal,and multi-decadal scales,caused by the periodic oscillations of precipitation,and El Nio/Southern Oscillation(ENSO)affects water discharge by influencing precipitation distribution and contributes to periodic varations in precipitation and water discharge at interannual timescale.The water discharge and sediment load of the Huanghe River have decreased since the 1960s under the influence of precipitation and huamn activities,and human activities attribute more than precipitation to the reduction in the water discharge and sediment load,furthermore,water abstraction and water-soil conservation practices are the main causes of the decrease in water discharge and sediment load,respectively.The reduction in sediment load has directly impacted on the lower reaches of the Huanghe River and the river delta, causing considerable erosion of the river channel in the lower reaches since the 1970s along with River Delta changing siltation into erosion around 2000. 相似文献
10.
Clay minerals and geochemistry of the bottom sediments in the northwestern East China Sea 总被引：1，自引：0，他引：1
Jeungsu YOUN Shouye YANG Yong Ahn PARK 《中国海洋湖沼学报》2007,25(3):235-246
Clay minerals of 34 sediments collected from the northwestern continental shelf of the East China Sea have been determined by X-ray diffraction analysis. The clay mineral distribution is mainly controlled by the sediment source and the dominant circulation pattern. The predominant clay mineral in our study area is illite comprising more than 67% of the whole clay fraction. The highest concentration of illite (>68%) is found in the southeastern offshore parts beyond the reach of terrigenous input from the Jeju Island. It means that these illites are largely transported by the Kuroshio Current from the South China Sea (SCS). Smectite is highly concentrated in the northwest middle part and in the outer-shelf mud patch. It seems to be due to the high supply of smectite transported from China where fine-grained sediments are discharged from modern and ancient Huanghe (Yellow) River. The relatively high abundant kaolinite is likely derived from the Changjiang (Yangtze) River via the Taiwan Warm Current. In contrast, large amounts of chlorite and high chlorite/kaolinite ratios occur in the northwestern area, reflecting the transportation by the Yellow Sea Coastal Current from the southern Yellow Sea. The discrimination diagrams clearly show that the sediments in the northwestern East China Sea are ultimately sourced from Chinese rivers, especially from the Huanghe River, whereas the sediment in the northeast part might come from the Jeju Island. The muddy sediments of the Changjiang River’s submerged delta have much lower 87Sr/86Sr ratios (0.716 2–0.718 0) than those of the Shandong Peninsular mud wedge (0.721 6–0.724 9), which are supposed to be originated from the Huanghe River, suggesting the distribution pattern of 87Sr/86Sr ratios as a new tracer to discriminate the provenance of shelf sediments in the study area. The 87Sr/86Sr ratios of the outer-shelf muddy sediments ranged from 0.7169 to 0.7216 in a wide range and was between those of the Huanghe River and Changjiang River sediments, suggesting multiple sources of the sediment in the area. 相似文献
11.
INTRODUCTIONPhosphorus (P)isanimportantlimitingelementinglobaloceanicproductivity (Holland ,1 978) ,soknowledgeofPisakeytobetterunderstandingofthecyclingofcarbon ,nitrogen,sulfur,andothernu trientelements.Inasimplemassbalancemodel,thelevelofdissolvedPintheoceanisafunctionoftherateofinputviarivers,andtherateofoutputviadepositioninsediments.Inthepresentstudy,thefocusisontheriverinePinputbytheHuangheRiver (YellowRiver)totheBohaiSea,andespeciallyontheamountofPsolubilizedfromsolidphasesupo… 相似文献
12.
Ma Yanyan Li Guangxue Ye Siyuan Zhang Zhiheng Zhao Guangming Li Jingyang Zhou Chunyan Ding Wenjie Yang Xin 《中国海洋湖沼学报》2010,28(6):1362-1370
The water and sediment discharge regulation (WSDR) project, which has been performed since 2002 before flood season every
year, is of great significance to the river management in China. Until 2007, six experiments have been fulfilled to evaluate
the effect of the project on the natural environment. To fill the gap of investigations, a study on flood and suspended sediment
transportation and channel changing along the distributary channel of the Huanghe (Yellow) River was conducted during the
WSDR project period in 2007. The lower channel was scoured rapidly and the channel became unobstructed gradually several days
after the flood peak water was discharged from the Xiaolangdi Reservoir. Within four days after the flood peak at 3 000 m3/s entered the distributary, the channel in the river mouth area was eroded quickly. Both the mean values of area and depth
of the main channel were tripled, and the maximum flood carrying capacity increased to 5 500 m3/s or more. Then, the river channel was silted anew in a very short time after completion of the WSDR. Favored by the WSDR
project, the river status in April 2008 became better than that of the year before. The adjustment ranges of main channel
parameters were about 30%, 10%, and 10% at sections C2, Q4, and Q7, respectively. The process of rapid erosion-deposition
was more active 15 km away in the channel from the river mouth due to the marine influence. It is reasonable for discharging
sediment at concentration peak from Xiaolangdi Reservoir at the end of the flood peak. As a result, the sediment peak reached
the river mouth about two days later than that of the water current. In addition, the WSDR project has improved the development
of the estuarine wetland. Wetland vegetation planted along the river banks restrained the water flow as a strainer and improved
the main channel stability. It is suggested to draw water at mean rate of 150 m3/s from the Huanghe River during flood periods, because at the rate the water in the wetland would be stored and replenished
in balance. Moreover, we believe that cropland on the river shoal of the lower Huanghe River should be replaced by wetland.
These activities should achieve the Huanghe River management strategy of “To concentrate flow to scour sediment, stabilize
the main channel, and regulate water and sediment”. 相似文献
13.
Ｒｉｖｅｒｗａｔｅｒｒｅｓｏｕｒｃｅｉｓｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔｃｏｍ ｐｏｎｅｎｔｏｆｗａｔｅｒｒｅｓｏｕｒｃｅｓｉｎＣｈｉｎａ .ＣｏｍｐｒｅｈｅｎｓｉｖｅａｎｄｓｐｅｃｉｆｉｃｒｅｓｅａｒｃｈｅｓｏｎｒｉｖｅｒｗａｔｅｒｃｈｅｍｉｓｔｒｙｉｎＣｈｉｎａｈａｖｅｂｅｅｎｃａｒｒｉｅｄｏｕｔｓｉｎｃｅｔｈｅ 1950ｓ.Ｔｈｅｏｂ ｊｅｃｔｉｖｅｏｆｔｈｉｓｐａｐｅｒｉｓｔｏｒｅｖｉｅｗｔｈｅｐｒｏｇｒｅｓｓｉｎｔｈｅｒｅｓｅａｒｃｈｏｎｒｉｖｅｒｗａｔｅｒｃｈｅｍｉｓｔｒｙｉｎＣｈｉｎａ ,ｅｓ… 相似文献
14.
根据收集到的日照市海岸带浅地层剖面测量调查资料,把多条浅地层剖面中出露的古河道断面推测性地连接起来,重建了以往的古河道体系,综合分析了日照市海岸带古河道的分布特征。日照近海区域存在一个主干河道呈SW-NE走向的梳状河道网,古河道形成于距今约4.4万a的末次冰期。古河道的形成是河流的侵蚀、搬运、沉积及后期的海平面上升、潮汐改造等多种因素共同作用的结果。在末次冰期,研究区内气候湿润,河流流速较大,河流搬运泥沙的能力较强,长期侵蚀作用形成下切古河道,在古河道中容易形成淤积较多河流携带的砂体。古河道断面形态主要呈U形、V形、W形、箱形和倒梯形。主干河道北西侧,分支河道较密,南东侧分支河道较稀疏。主河道长约40km,横截面由南西向北东逐渐变宽,最宽处达4km。分支河道多数以NW向为主,少数为NE向,长度介于8~20km之间,宽度约为1~3km。古河道主要位于16~24m水深的闭合深度以外区域,对其中的砂体经过粒度筛选可作为将来进行人工抛沙的砂源。 相似文献
15.
The sedimentary history of a Huanghe(Yellow)River delta lobe can be divided into four stages.In the first stage,the crevasse splays and short-lived distributary channel deposits in the subaerial deltaand sheet silt in the subaqueous delta were well developed.In the second stage,further differentiationof sedimentary environments occurred in the subaerial delta lobe(distributary channel,natural levee,flood plain,central lower delta plain and lateral lower delta plain)and the subaqueous delta lobe(prodelta,delta front and delta lateral).In the third stage,crevasse splay and short-lived distributarychannel deposits mostly occurred in the lower or lower-middle part of the subaerial delta lobe,andsheet silt accumulated off the river mouth.In the fourth stage,the abandoned lobe was reworked.The common vertical sequence of the modern Huanghe River delta showed alternating clayey silt andsilt layers.A complete sequence from prodelta to upper delta plain was commonly composed of twoor more delta lobes. 相似文献
16.
To decipher the sedimentary evolution and environmental changes since the late Last Deglaciation, two gravity cores were analyzed from the western North Yellow Sea (NYS). The two cores (B-L44 and B-U35) were sampled for grain size, clay minerals, detrital minerals, and 14C dating. They are comparable in lithofaies, and the observed succession was divided into four depositional units based on lithology and mineral assemblages, which recorded the postglacial transgression. Depositional unit 4 (DU 4) (before 11.5 ka) was characterized with enrichment in sand, and was interpreted as nearshore deposits in shallow water during the Younger Dryas Event. DU 3 (11.5-9.6 ka) displayed a fining-upward succession composed of sediments from local rivers, such as the Huanghe (Yellow) River, and from coastal erosion, which clearly were related to the Early Holocene transgression. Stable muddy deposition (DU 2) in NYS began to form at about 9.6 ka, which received direct supply of fine materials from the Shandong subaqueous clinoform. It is believed that the Yellow Sea circulation system played a major role in controlling the formation of fine sediment deposition in DU 1 (after 6.4 ka) after the sea level maximum. 相似文献
17.
Ｉ．ＧＲＡＩＮＳＩＺＥＯＦＬＯＡＤ１．ＧｒａｉｎＳｉｚｅｏｆＬｏａｄｆｒｏｍｔｈｅＨｕａｎｇｈｅＲｉｖｅｒＴｈｅｓｕｓｐｅｎｄｅｄｌｏａｄｓａｍｐｌｅｄｆｒｏｍｔｈｅＨｕａｎｇｈｅＲｉｖｅｒｍａｉｎｌｙｃｏｍｐｒｉｓｅｓｓｉｌｔｗｈｏｓｅｃｏｎｔｅｎ... 相似文献
18.
THE DESTRUCTION OF ANCIENT ECOLOGICAL ENVIRONMENT AND THE MOVEMENT OF CIVILIZATION CENTER IN CHINA 总被引：1，自引：0，他引：1
孔繁德 《中国地理科学(英文版)》1992,2(4):382-388
China is one of the ancient civilization countries. Owing to the blind reclamation, the vegetation had been destroyed, causing soil erosion and desertification, and making the civilization center move to the Changjiang (Yangtze) River valley from the Huanghe (Yellow) River. This movement began in the Qin and Han dynasties (221 B.C-220 A.D.) because at that time the large-scale reclamation was felled, the grassland was reclaimed into farmland, the vegetation was seriously destroyed in the loess and north of the Huanghe River, and the climate was getting colder; and the turn from north to south occurred in the Sui and Tang dynasties (581-907 A.D.) and completed in the Song Dynasty (960-1279 A.D.). However, at present the vegetation damage of the Changjiang River valley is very serious too and the silt carrying capacity of the Changjiang River is increasing sharply; thus the Changjiang River is in danger of becoming a second Huanghe River, so we must pay attention to the protection of ecological environmen 相似文献
19.
According to the analysis of grain size, mineral composition and inclusion in quartz grain of the suspended and bed load sampled
from the Changjiang (Yangtze) River and the Huanghe (Yellow) River, the authors reveal the differentiation of loads between
the two rivers. In the Huanghe River the size of suspended load is coarser than that in the Changjiang River, while the bed
load is on the contrary. Through heavy mineral analysis, the biotite content of the Huanghe River loads is much higher than
that of the Changjiang River, and the monomorillonite content of the former is about two times higher than the latter. All
those may be attributed to the effects of different material sources and hydraulic conditions on load. The analysis of inclusion
in quartz grain definitely illustrates the environmental difference of material sources between the two rivers. In the meantime,
it provides a new method in seeking source of river load.
Subsidized by the National Natural Science Foundation. This paper is attributed to careful guidance from Prof. Wang Ying &
Prof. Shi Yunliang. 相似文献
20.
黄河中游黄土高原区河川基流特点及变化分析 总被引：2，自引：0，他引：2
由于气候变化和人类活动的影响。黄土高原河川基流呈显著下降趋势。对黄河径流量减少产生一定影响。采用日流量过程线切割法计算了河龙区间黄土高原主要支流的基流量。结合地形地貌、水文地质条件，分析了不同地貌类型支流基流的特点，初步分析了影响基流变化的各种因素。认为河龙区间基流变化对黄河水资源影响较大。 相似文献