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1.
黄河中下游水沙变化趋势 总被引：2，自引：0，他引：2
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
2.
黄河中游流域环境要素对水沙变异的影响 总被引：15，自引：7，他引：15
目前 ,黄河中游地区流域的水沙变化主要以水文法和水保法研究为主。由于黄河中游具有明显的自然地带性分布特征 ,流域系统的水沙过程受到环境要素的综合影响。本文根据黄河中游河口镇至龙门区间已控一级支流的测站资料 ,采用地理环境要素法分析水沙变异及成因。研究表明 ,河龙区间流域径流量和输沙量与地理环境因子的影响密切相关。 2 0世纪 70年代以来 ,降雨减水减沙作用不断减小 ,随着水土保持措施的提高 ,人类活动减水减沙所占比重不断增大。 70年代与 80年代气候波动和人类活动影响的平均减水减沙作用分别为5 3 4 %、 2 8 6 %和 4 6 6 %、 71 4 %。 相似文献
3.
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
4.
This paper examines the changes in the time series of water discharge and sediment load of the Yellow River into the Bohai Sea. To determine the characteristics of abrupt changes and multi-scale periods of water discharge and sediment load, data from Lijin station were analyzed, and the resonance periods were then calculated. The Mann-Kendall test, order clustering, power-spectrum, and wavelet analysis were used to observe water discharge and sediment load into the sea over the last 62 years. The most significant abrupt change in water discharge into the sea occurred in 1985, and an abrupt change in sediment load happened in the same year. Significant decreases of 64.6% and 73.8% were observed in water discharge and sediment load, respectively, before 1985. More significant abrupt changes in water discharge and sediment load were observed in 1968 and 1996. The characteristics of water discharge and sediment load into the Bohai Sea show periodic oscillation at inter-annual and decadal scales. The main periods of water discharge are 9.14 years and 3.05 years, whereas the main periods of sediment load are 10.67 years, 4.27 years, and 2.78 years. The significant resonance periods between water discharge and sediment load are observed at the following temporal scales: 2.86 years, 4.44 years, and 13.33 years. Water discharge and sediment load started to decrease after 1970 and has decreased significantly since 1985 for several reasons. Firstly, the precipitation of the Yellow River drainage area has reduced since 1970. Secondly, large-scale human activities, such as the building of reservoirs and floodgates, have increased. Thirdly, water and soil conservation have taken effect since 1985. 相似文献
5.
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
6.
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
7.
黄河下游2300年以来沉积速率的变化 总被引：11，自引：0，他引：11
采用沉积学方法提取沉积速率的记录,利用历史文献研究的方法提取气候与人类活动变化的信息,对黄河下游2300年以来的沉积速率的变化及其与气候、植被及人类活动的关系进行了研究,揭示黄河流域地貌系统对气候变化及人类活动所导致的土地覆被、土地利用方式变化的响应过程。研究表明,黄河流域地貌系统中的下游沉积带对于中游侵蚀带的响应是灵敏的,流域植被和土地利用方式的变化,是导致下游河道沉积加速的主导因素;这种变化主要取决于人类活动,同时与气候的变化也有一定关系。在沉积加速的过程中,公元7世纪至10世纪以及18世纪中叶以来,表现为两个突变时期。 相似文献
8.
近60 年黄河入海水沙多尺度变化及其对河口的影响 总被引：9，自引：0，他引：9
基于1950-2008 年利津站月均径流量和输沙量的时间序列资料,采用小波分析的方法研究了黄河入海水沙多尺度变化,并结合不同年份的黄河口岸线和口门地形资料分析了水沙变化对河口演变的影响。结果表明：黄河入海水沙具有3 个不同时间尺度的显著周期变化,其与厄尔尼诺事件有关,不同尺度下的入海水沙丰枯变化不同;受流域降水和人类活动的影响,入海水沙长期呈减少趋势,并具有阶段变化的特征;入海水沙变化深刻影响着河口演变,不同时期行水河口的岸线延伸速率与河口来沙量有关,亿t 泥沙岸线延伸量与来沙系数显著相关,自1976 年清水沟流路入海以来,河口水下三角洲表现为淤积,淤积程度与入海水沙量密切相关。 相似文献
9.
JIONGXIN XU 《Geografiska Annaler: Series A, Physical Geography》2008,90(2):173-186
The amount of the sediment deposition in the Yichan-Wuhan reach of the middle Yangtze River (also known as Changjiang River) has been determined using the concept of sediment budget at the channel-reach scale. The fill-scour processes of the middle Yangtze River were studied during the period 1956–1997 in response to the variation in sediment load and flow inputs. The results show that 13.3% of the net input of sediment was deposited in the studied river reach. Since 1956, the output sediment load of the studied reach increased with time to 1981, followed by a decline. The increase in output before 1981 can be related to the man-made bend neck-cutoff which caused a decrease in the sediment load diverted through the 'three outfalls' (i.e. the three distributaries from the Yangtze main stem to the Dongting Lake) and increased the sediment-carrying capacity of the river. Thereby, the river could transport more sediment to the outlet of the studied river reach. The decrease in the sediment load output after 1984 was directly due to the decreased sediment load at Yichang station. Multiple regression equations have been established to assess the contributions of influencing factors to the variation in sediment deposition amount in the studied river reach. 相似文献
10.
随着气候的变化以及人类活动的加剧,世界上一些河流的径流和输沙量发生了明显的改变。查明流域的水沙特征、变化趋势及驱动因素是流域治理和管理中面临的重要问题。以黄河上游的十大孔兑为研究对象,利用1958-2015年的实测资料,采用线性趋势法、非参数Mann-Kendall趋势检验法对典型孔兑毛不拉、西柳沟、罕台川的年降雨、径流、泥沙、洪水过程进行了系统分析。结果表明：毛不拉和西柳沟年水沙序列下降趋势显著,罕台川下降趋势不显著,但近10 a比之前水沙明显减少;三个孔兑21世纪和20世纪观测到的2次洪水过程相比,产生洪水的降雨差别不大,但后一次洪峰流量和含沙量都显著降低;与1990年之前相比,1991-2015年各孔兑高强度降雨变化程度相对水沙变化不大。通过遥感影像解译,发现自20世纪90年代以来,随着退耕还林还草、封禁、休牧等水土保持工程陆续实施,十大孔兑土地利用变化显著,植被盖度明显增加,由此改变了该区域降雨-产流-产沙过程,引起1990年以后产水产沙的剧烈减少。 相似文献
11.
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
12.
基于高要（西江）、石角（北江）和博罗（东江）水文站1954-2011 年的连续径流量和输沙率资料,采用Mann-Kendall 非参数秩次检验和小波分析的方法,分析珠江流域的入海水沙通量变化特征。结果显示：（1）1954-2011 年珠江的入海径流量没有明显变化趋势,但输沙率呈明显下降趋势,其间不同阶段的变化趋势不同：1954-1983 年珠江水沙均处于增长阶段,该阶段气候变化和人类活动对输沙的贡献率分别是70%和30%;1984-1993 年珠江水沙通量呈先降后升（1989 年是转折点）波动阶段,主要与气候变化有关;1994-2011 年珠江的水沙通量均呈下降趋势;气候变化和人类活动对输沙率下降的贡献率分别是20%和80%。（2）龙滩水库蓄水后的2007-2011 年与2006 年以前相比,珠江年均入海径流量减少了14%,而年均入海输沙率是减幅达到70%。这一时期水库蓄水和水土保持对输沙率减少的贡献率达到90%以上;（3）珠江的水沙通量变化具有明显年代际周期和年际周期变化特征,且不同子流域的周期有所不同。例如西江的径流量主要存在24 年和13 年的年代际周期以及4~7 年的年际周期,而输沙率主要存在16 年左右和10 年左右的年代际周期和4~7 年的年际周期;北江径流量主要存在12 年左右年代际周期和2 年左右以及8 年左右的年际周期和和输沙率年代际周期主要13-16 年,而年际周期是4~7 年和2~3 年;东江的径流和输沙率主要存在12 年左右年代际周期和2 年左右以及6 年左右的年际周期。这些年代际和年际变化周期与珠江流域降雨量的变化周期有较好关联性。 相似文献
13.
基于Budyko假设和分形理论的水沙变化归因识别——以北洛河流域为例 总被引：1，自引：0，他引：1
全球气候变化及人类活动深刻影响了区域水文过程,进行水沙变化归因识别对流域生态保护和高质量发展尤为重要。基于Budyko假设和分形理论,采用弹性系数法,对北洛河流域上（丘陵沟壑区）、中（土石山林—高塬沟壑区）、下游（渭北旱塬农区）3种不同地貌和植被类型区1959—2019年的水、沙通量变化进行归因分析。结果表明,北洛河上、中、下游径流量均显著减少,由20世纪60年代的35 mm、32 mm、34 mm,减少到21世纪10年代的19 mm、24 mm、6 mm,60 a减少率分别为0.3 mm a-1、0.2 mm a-1、0.4 mm a-1。上游输沙量极显著减少,中游降低趋势不显著,下游显著减少,由20世纪60年代的99×106 t、8×106 t、3×106 t,减少到21世纪10年代的10×106 t、3×106 t、0.3×106 t,60 a减少率分别为1.5×106 t a-1、0.04×106 t a-1、0.1×106 t a-1。20世纪70年代以来,上游径流变化逐渐受人类活动影响,且影响程度逐渐增强,21世纪10年代人类活动贡献率达66.3%;气候变化是中游径流变化的主控因子,21世纪10年代降雨和潜在蒸散发的贡献率分别为77.0%和20.2%;下游径流减少主要为人类活动影响,21世纪10年代其贡献率为64.3%。对比20世纪60年代流域输沙量变化始终受人类活动主导,21世纪10年代人类活动对上、中、下游输沙量减少的贡献率分别为80.7%、59.2%和92.7%。上游人类活动对输沙量减少的贡献中,退耕还林等沟坡措施和沟道工程措施分别为39.0%、42.7%,中、下游人类活动贡献的估算结果反映出高植被覆盖区和农区汲水灌溉对区域水、沙的影响特征。 相似文献
14.
Based on hydrological data observed at Lijin gauging station from 1950 to 2008, the temporal changes of water discharge and sediment load of the Yellow River into the sea were analyzed by the wavelet analysis, and their impacts on the estuary were investigated in different periods based on the measured coastline and bathymetry data. The results show that: (1) there were three significant periodicities, i.e. annual (0.5-1.0-year), internnual (3.0-6.5-year) and decadal (10.1-14.2-year), in the variations of water discharge and sedi- ment load into the sea, which might be related to the periodic variations of El Nino and Southern Oscillation at long-term timescales. Variations of water discharge and sediment load were varying in various timescales, and their periodic variations were not significant during the 1970s-2000s due to strong human disturbances. (2) The long-term variation of water discharge and sediment load into the sea has shown a stepwise decrease since the 1950s due to the combined influences of human activities and precipitation decrease in the Yellow River Basin, and the human activities were the main cause for the decrease of water discharge and sediment load. (3) The water discharge and sediment load into the sea greatly influenced the evolution of the Yellow River Estuary, especially the stretch rate of coastline and the deposition rate of the sub-aqueous topography off the estuary which deposited since 1976. 相似文献
15.
1950-2008年黄河入海水沙变化(英文) 总被引：1，自引：0，他引：1
Based on hydrological data observed at Lijin gauging station from 1950 to 2008, the temporal changes of water discharge and sediment load of the Yellow River into the sea were analyzed by the wavelet analysis, and their impacts on the estuary were investigated in different periods based on the measured coastline and bathymetry data. The results show that: (1) there were three significant periodicities, i.e. annual (0.5-1.0-year), internnual (3.0-6.5-year) and decadal (10.1-14.2-year), in the variations of w... 相似文献
16.
黄河上中游产水产沙系统与下游河道沉积系统的耦合关系 总被引：33，自引：4，他引：33
本文在黄河为例，动用数理统计方法，研究了河流流域系统中产水产沙子系统与河道沉积子系统之间的关系，得到了描述这种耦合关系的多元回归模型。运用这一模型，可以定量回答来自上中游不同来源区的泥沙，各有多大比例淤在下游河道中的问题。 相似文献
17.
气候变化对径流的影响是全球变化研究领域的重点问题。论文采用BCC-CSM1-1模拟的过去千年(850—2012年)气候与水文变化数据,基于Budyko假设与傅抱璞公式开展了中世纪气候异常期(MCA)、小冰期(LIA)和现代暖期(MWP)黄河中、上游径流变化及其归因分析。结果表明：① 在3个气候特征期之间,上游地区径流与气候冷暖变化位相相同,MWP时期径流最高,LIA时期径流最低;中游地区径流则与气候冷暖变化位相相反,LIA径流最高,MCA径流最低。② 径流对各因子的敏感性不仅存在地理差异,而且受特征期之间气候冷暖转变的影响。中游地区径流对降水和潜在蒸发的弹性系数(绝对值)大于上游,且在冷转暖过程中的弹性系数(绝对值)略大于暖转冷过程。同时,持续偏暖过程中、上游地表变化的弹性系数(绝对值)均明显大于暖转冷与冷转暖过程。③ 3个特征期之间径流差异主要由降水主导,地表变化影响甚微,但潜在蒸发的作用存在地域差异,上游地区潜在蒸发部分抵消了降水变化的贡献而中游地区潜在蒸发则加强了降水导致的径流变化。研究量化了黄河流域各因子对过去千年百年尺度径流变化的贡献,明确了不同气候转变期各因子贡献的差异,为更好地研究径流量多尺度变化及其成因奠定了基础。 相似文献
18.
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
19.
水沙条件对黄河下游河道输沙功能的影响 总被引：4，自引：3，他引：1
提出河道输沙功能指标Fs为进入某一河道的泥沙总量(干流与支流输入沙量之和)与输出这一河道的泥沙量之比。河道输沙功能与来水量和来沙量有密切关系,若来水减少,来沙增多,则河道输沙功能减弱。来沙中大于0.05 mm粗泥沙含量百分比与河道输沙功能指标成负相关。来沙系数、特别是粗泥沙的来沙系数,是决定黄河下游输沙功能的重要因子;来沙系数越大,则河道输沙功能指标越低。场次洪水的输沙功能指标随场次洪水最大含沙量的增大而降低,历年河道输沙功能指标随各年中高含沙水流频率的增高而降低。小浪底水库修建后,为我们通过调水调沙提高河道输沙功能提供可能。研究表明,场次洪水平均含沙量35 kg/m3,或场次洪水平均来沙系数为(0.015 kg·s)/m6,是在调水调沙中实现河道输沙功能优化的最优含沙量和最优来沙系数,平滩流量则是实现河道输沙功能最大化的最优流量级。 相似文献
20.
黄河下游河道输沙功能的时间变化及其原因 总被引：6，自引：4，他引：2
以输出某一河道的泥沙总量与进入这一河道的泥沙量之比来定义河道输沙功能,以此为指标研究了黄河下游输沙功能的时间变化。研究表明,近50年来黄河下游河道输沙功能表现出随时间而减小的明显趋势。在总的减小趋势中,由于水库运用方式与下游水沙组合的不同,河道输沙功能指标具有明显的差异,可以划分为6个阶段。19861997年,由于降水偏少,且人类大量引水,黄河下游进入连续枯水的水文系列,河道萎缩,输沙功能迅速降低,此时段中输沙功能指标的时段平均值为0.62,为有水沙记录以来最低的时期。对于黄河下游输沙功能指标与流域因子和河道特性因子的时间变化系列进行了比较,以揭示输沙功能减小的原因。结果表明,黄河下游河道输沙功能指标与流域平均年降水量、兰州站和三门峡站汛期径流占年径流百分比、游荡段典型断面平滩水位下断面面积、花园口站和高村站水面比降等因子有同步减小的关系,并随流域水土保持面积、人类引水量及其占天然径流量比率的增大而增大,说明这些因子的变化导致了黄河下游输沙功能的减弱。 相似文献