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1.
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   

2.
黄河流域环境对水资源开发承受力的思考   总被引:8,自引:0,他引:8  
尹国康 《地理学报》2002,57(2):224-231
根据黄河1919-1999年系列水沙资料,系统分析了其下游水沙变化时空过程,揭示了其发生断流原因及由此引发的环境问题,模拟了不同历史时期水情条件下环境用水需求量,并对如何提高黄河水资源开发承受能力,如何满足其环境用水提出看法。  相似文献   

3.
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   

4.
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   

5.
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  
师长兴 《地理研究》2021,40(4):1125-1133
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   

6.
7.
The Yellow River is one of the largest riverine sediment routing system in the world. Like many other rivers, the sediment load of the Yellow River can not be regarded as constant in its long history due to changes in climate and human activities. This study determined sediment storage on the floodplains of the lower Yellow River in five historical periods after the year 602 bc mainly based on data of 93 boreholes, 182 radiocarbon dates in the Huang‐Huai‐Hai Plain and maps of historical changes of the lower Yellow River channel. Furthermore, the mean annual sediment outputs from the upper and middle reaches of the Yellow River were calculated in the five periods through investigating the sediment delivery ratio of the lower Yellow River under different conditions of artificial levees. Our findings suggest that the sediment output from the upper and middle Yellow River increased slowly before the year around 1128, but was lower than half of the current value on average. It has been in the past about 1000 years that the sediment output from the upper and middle Yellow River escalated. The Loess Plateau is the principal sediment source of the Yellow River. The comparison of historical changes in sediment load of the lower Yellow River with those in the natural conditions and in human activities on the plateau reveals that the changes in sediment yield from the plateau could be attributed mainly to the variations of population, cultivating area, and climate changes on the plateau.  相似文献   

8.
Sedimentation in the lower reaches of the Yellow River is a major problem requiring implementation of large-scale control measures in the upper and middle drainage basin. For maximum benefit, major sediment generation areas must be delimited. For this purpose, the upper and middle drainage basin of the Yellow River has been divided into four major sediment and water source areas. A series of databases of runoff and sediment yields from these source areas and for the corresponding quantities of sedimentation in the lower Yellow River channel have been established. On this basis, a set of multiple-regression equations has been established that define the relationships between sedimentation in the lower Yellow River and the yearly or event-based runoff and sediment yields from the four source areas or subsystems. Based on the regression equations obtained, the contribution of the four major source areas to the sedimentation in the lower Yellow River channel can be estimated. The results obtained indicate that, given other factors, for each ton of sediment reduced from the coarse-sediment producing area (CSA), the sediment deposited in the lower Yellow River would be reduced by 0.455 ton; for each ton of sediment reduced from the fine-sediment producing area (FSA), the sediment deposited in the lower Yellow River would be reduced by 0.154 ton only. Therefore, if limited erosion control measures are applied to the coarse-sediment producing area, the benefits for sedimentation reduction in the lower Yellow River will be much larger than if similar resources are applied to the fine-sediment producing area.  相似文献   

9.
黄河中下游水沙变化趋势   总被引:2,自引:0,他引:2  
齐璞 《地理研究》1989,8(2):74-81
本文论述由于黄河上游清水区水资源的优先开发,中上游地区工农业用水的增长,而黄河中游地区的水土保持和支流治理的减沙作用不甚明显,龙羊峡水库投入运用后,汛期进入河口镇的水量大幅度减少,使汛期进入黄河下游的基流减小含沙量增加,高含沙洪水出现的机会增多.面临水少沙多的不利情况,应加强宽浅河道的改造及利用窄深河道输送高含沙水流的研究.  相似文献   

10.
薛春汀  周良勇 《地理研究》2010,29(11):1961-1970
现在的洪泽湖和淮河中游河道不断淤高,致使淮河中游洪涝不断。入洪泽湖后淮河水主要流入长江。而苏北北部地区需要水,因入海泥沙数量太少而致海岸侵蚀问题不能根本解决,那里需要淮河的泥沙。为改变这种不合理的格局。在洪泽湖北岸和浅水区开挖与洪泽湖分离的河道,连接完成远期工程的淮河入海水道和拓宽、挖深的淮沭河—北六塘河—新沂河水道,使淮河水沙只经过这两条水道到达黄海,改变淮河水沙不合理的资源分配。新水道路程短,比降大,使洪泽湖和淮河中游河道不再淤高,并将进一步使淮河中游水道刷深,减轻淮河中游洪涝灾害,并为洪泽湖湖底高程降低创造条件。通过分析现在淮河的输沙量、输沙模数,与历史时期和其他流域对比,认为连云港至射阳河口这段海岸将改变为北部稳定,南部缓慢进积,形成新的淮河三角洲,彻底解决苏北海岸侵蚀问题。  相似文献   

11.
The Yellow River basin is well known for its high sediment yield. However, this sediment yield has clearly decreased since the 1980s, especially after the year 2000. The annual average sediment yield was 1.2 billion tons before 2000, but has significantly decreased to 0.3 billion tons over the last 10 years. Changes in discharge and sediment yield for the Yellow River have attracted the attention of both the Central Government and local communities. This study aimed to identify the individual contributions of changes in precipitation and human activities (e.g. water conservancy projects, terracing, silt dams, socio-economic and needs, and soil and water conservation measures) to the decrease in discharge and sediment yield of the Yellow River. The study used both improved the hydrological method and the soil and water conservation method. The study focused on discharge analysis for the upper reaches and the investigation of sediments for the middle reaches of the river. The results showed that discharge and sediment yield have both presented significant decreasing trends over the past 50 years. Precipitation showed an insignificant decreasing trend over the same period. The annual average discharge decreased by 5.68 billion m3 above Lanzhou reach of the Yellow River from 2000 to 2012; human activities (e.g. socio-economic water use) contributed 43.4% of the total reduction, whereas natural factors (e.g. evaporation from lakes, wetlands and reservoirs) accounted for 56.6%. The decrease in annual discharge and sediment yield of the section between Hekouzhen station and Tongguan station were 12.4 billion m3 and 1.24 billion tons, respectively. Human activities contributed 76.5% and 72.2% of the total reduction in discharge and sediment yield, respectively, and were therefore the dominant factors in the changes in discharge and sediment yield of the Yellow River.  相似文献   

12.
黄河中游土壤侵蚀与下游古河道三角洲演化的过程响应   总被引:10,自引:7,他引:10  
根据黄土高原土壤侵蚀的周期特点,结合华北平原古河道,古三角洲的演化过程,应用泥沙输移的过程响应,分析了晚更新世以来黄河中游黄土高原土壤侵蚀与下游古河道,三角洲演化的关系,在人类历史之前,黄土高原土壤侵蚀基本上遵循自在生态环境演化规律,强裂侵蚀期发生在干冷向湿湿气候转化的过渡期,在强裂侵蚀的初期是古道形成期,强烈侵蚀期发生在干冷向温湿气候转化的过渡期,在强裂侵蚀的期是古河道形成期,强烈侵蚀的外营力迭加了人为作用,黄河下游河游泳以改道,三角洲横向扩展发生在强烈侵蚀的衰退期,人类历史时期,土壤侵蚀的外营力迭加了人为作用,破坏了地质历史时期的规律性,土壤侵蚀强度越来越强,基本上按照旱涝变化频率而演化,干冷期降雨不均匀系数增加,土训侵蚀加重,径流量较少,河床以淤积为主,是古河道形成期,正常年黄河泥少输移比接近于一,是三角洲进积期,温湿期降雨量增加,径流量加大,下游河流改道,三角洲横向发展。  相似文献   

13.
近百年来长江口启东嘴潮滩沉积物质来源及定量估算   总被引:2,自引:0,他引:2  
张云峰  张振克  任航  高磊  丁海燕 《地理学报》2018,73(11):2105-2116
河流入海输沙是海岸稳定的重要物质基础。启东嘴潮滩位于长江北支口门,与江苏海岸线交汇,陆海相互作用强烈。利用电感耦合等离子体质谱仪测定了岩芯沉积物QDZ-1的地球化学元素。根据地球化学元素的分布特征和富集系数,分析了物源指示意义,表明启东嘴潮滩沉积物受到长江物质和南黄海物质的共同影响。基于地球化学元素的沉积物端元定量判识方法,对不同物质来源的贡献率进行了定量估算。在1930年前启东嘴潮滩沉积物主要来自长江的入海输沙,贡献率为68.1%,随着长江北支河槽的衰退,贡献率逐渐减少,在1930-1972年间为38.5%,到1972年后减少到17.5%。苏北沿岸流携带向南输运的南黄海物质,贡献率逐渐增加,在1930年前为27.1%,在1930-1972年间为55.6%,到1972年后增加到75.9%,成为启东嘴潮滩主要物质来源。沉积物来源的阶段性变化,在时间上与北支水动力的阶段性变化基本吻合。  相似文献   

14.
黄河是世界闻名的多沙性河流,历史时期就不断淤积、决口改道,且淤积速度不断加快,决口改道的频率也在不断增加。黄河下游地上河的发展和演变是自然因素和人类活动综合作用的结果。历史时期流域内人口的增加、耕作方式的改变及其对植被造成的破坏都对中游地区侵蚀的加剧、来沙的增加,以及下游地区河道的淤积及决口改道的发生带来不同程度的影响。  相似文献   

15.
黄河游荡河段河床形态调整对洪水过程的响应   总被引:1,自引:1,他引:1  
以黄河流域1950~1985年200余场洪水资料为基础,并增加了最近的实验资料,分析了黄河下游游荡河段不同含沙量沙水过程中河床形态的调整过程,结果表明,由洪水过程所导致的河床形态变化是相当剧烈的。且与含沙量密切相关,表现出非线性的变化规律,当含沙量较小时,随含沙量的增大,洪水后河床宽深比增大,当含沙量增大到一定程度后再增大时,宽深比随含沙量的增大而减小,这一结果为修正Schumm关于河床形态变化的定性预测关系提供了新的依据。  相似文献   

16.
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   

17.
分析黄河口钓口河亚三角洲不同时期泥沙沉积速率和水沙条件变化,发现来沙输沙率是影响黄河三角洲沉积速率的主要因素,随输沙率增加三角洲泥沙沉积速率增大.来水流量和来沙粒度组成变化对沉积速率的影响不明显.还发现来水含沙量与三角洲泥沙淤积占来沙的比例(沉积比)之间为双值关系,在某一含沙量时沉积比达最大值.对比显示,在河口河道畅通,沙嘴突出时期,三角洲泥沙沉积比反而比河口改道初期大,意味着集中水流入海可能降低海流带走泥沙的比例.另外,根据前三角洲的地形测量资料分析发现,进入远海的泥沙随距离增加呈指数递减.对黄河口这些独特的泥沙扩散规律发生机理进行了深入分析.  相似文献   

18.
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   

19.
近60年黄河水沙变化过程及其对三角洲的影响   总被引:12,自引:2,他引:10  
为了了解黄河水沙变化过程及其对三角洲的影响,本文运用统计学方法对利津站1950-2007年的水沙数据以及流域人类活动引起的减水减沙数据进行了分析,结果表明:1950-2007年黄河人海水沙量明显减少,且年际波动比较剧烈.人类活动的影响是人海水沙量减少的主要原因.1950.2005年,水土保持年均减水减沙量分别为20.2亿m3和3.41亿t;工农业年均引水引沙量分别为251.64亿m3和2.42亿t;干流库区拦沙量,三门峡水库1960-2007年年均淤积1.45亿m3,小浪底水库1997-2007年年均淤积2.398亿m3.相比于花园口站的水沙量,下游河道以淤积为主,人海水沙量减少;以冲刷为主,人海水沙毋增加.当不同时期人海总水沙量比为0.0257 t/m3左右时,河口附近岸线延伸,三角洲面积增加.但近来年入海水沙量的急剧减少,特别是黄河口清8出汉以后,整个黄河三角洲由淤积转变为侵蚀,冲淤状态发生逆转的时间约在1997年.  相似文献   

20.
废黄河三角洲的演变*   总被引:20,自引:1,他引:19  
李元芳 《地理研究》1991,10(4):29-39
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   

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