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1.
Jiongxin Xu 《水文研究》2005,19(9):1871-1882
In the past 30 years, the measured annual river flow of the Yellow River has declined significantly. After adding the diverted water back to get the ‘natural’ annual river flow, the tendency of decrease can still be seen. This indicates that the river flow renewability of the Yellow River has changed. The river flow renewability is indexed as the ratio of annual ‘natural’ river flow to annual precipitation over a river drainage basin, where the ‘natural’ river flow is the measured annual river flow plus the annual ‘net’ water diversion from the river. By using this index, based on the data from the drainage area between Hekouzhen and Longmen stations on the middle Yellow River, a study has been made of the river flow renewability of the Yellow River in the changing environment of the past 50 years. The river flow renewability index (Irr) in the drainage area between Hekouzhen and Longmen in the middle Yellow River basin has been found to decline significantly with time. In the meantime, annual precipitation decreased, annual air temperature increased, but the area of water and soil conservation measures has been increased. It has been found that Irr is positively correlated with the areal averaged annual precipitation, but negatively correlated with annual air temperature. There is close, negative correlation between Irr and the area of water and soil conservation measures including land terracing, tree and grass planting and checkdam building, implying that water and soil conservation measures have reduced the river flow renewability. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

2.
Characteristics of annual runoff variation in major rivers of China   总被引：1，自引：0，他引：1  
The statistical properties of annual runoff in major rivers of China are studied based on the theory of stochastic process and technology of time series analysis. These properties include the characteristics of intra‐annual and inter‐annual variations of runoff, trends, abrupt changes and periodicities. The new findings from the intensive calculations and appropriate analysis of data in longer period are as follows: (i) compared with the nonuniformity of intra‐annual runoff before 1980, the nonuniformity of intra‐annual runoff in China generally decreased after 1980, except for Huaihe River and Songhua River; (ii) compared with the annual runoff before 1980, the annual runoff in China generally decreased after 1980 except for WangJiaba station in Huaihe River and Ha‐Erbin station in Songhua River; the frequency of continuous low flow and continuous high flow in Haihe River and the downstream of Yellow River is higher than those in other rivers in China; (iii) annual runoff shows a downward trend in major rivers of China especially in Haihe River, Liao River and the midstream and downstream of Yellow River; (iv) there exist certain abrupt changes of annual runoff in major rivers of China; the abrupt change‐points are different among different river basins; and (v) almost periodicities of annual runoff sequences in major rivers of China are generally 20 years below, that is, 3~7 and 12~20 years. The reasons for these changes are mainly caused by climate change and human activities. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

3.
We analyzed long daily runoff series at six hydrological stations located along the mainstem Yellow River basin by using power spectra analysis and multifractal detrended fluctuation analysis (MF-DFA) technique with aim to deeply understand the scaling properties of the hydrological series in the Yellow River basin. Research results indicate that: (1) the runoff fluctuations of the Yellow River basin exhibit self-affine fractal behavior and different memory properties at different time scales. Different crossover frequency (1/f) indicates that lower crossover frequency usually corresponds to larger basin area, and vice versa, showing the influences of river size on higher frequency of runoff variations. This may be due to considerable regulations of river channel on the runoff variations in river basin of larger basin size; (2) the runoff fluctuations in the Yellow River basin exhibit short-term memory properties at smaller time scales. Crossover analysis by MF-DFA indicates unchanged annual cycle within the runoff variations, implying dominant influences of climatic changes on changes of runoff amount at longer time scales, e.g. 1 year. Human activities, such as human withdrawal of freshwater and construction of water reservoirs, in different reaches of the Yellow River basin may be responsible for different scaling properties of runoff variations in the Yellow River basin. The results of this study will be helpful for hydrological modeling in different time scales and also for water resource management in the arid and semi-arid regions of China.  相似文献   

4.
Determining abrupt changes in runoff and sediment load may not only enhance identification of the principal driving factors for such changes but also help establish effective countermeasures for serious water deficit by managers in the Yellow River basin. We used the Mann-Kendall trend test and linear regression to determine trends and abrupt changes of runoff and sediment load during the period between 1950 and 2005, based on monthly hydrological data. Results show that runoff and sediment load decreased from 1950 to 2005, on annual or monthly time scales. Their changes are divided into three stages: fluctuating stage (1950–1970), slowly decreasing stage (1970–1980) and accelerated decreasing stage (1980–2005). The relationship between runoff and sediment load was most significant, and it can be expressed as a linear regression function. Precipitation was one of the most important climate factors affecting runoff before 1985, and the impact of human activities on runoff decrease grew strongly after 1985. Water balance analysis of the Yellow River basin indicates that natural climate change contributed about 55.3% and human activities about 44.7% to the runoff decrease after 1986.  相似文献   

5.
Due to the impacts of globe climate change and human activities, dramatic variations in runoff and sediment load were observed for the Yellow River. Analyses of nearly 65 years' data measured at main hydrologic-stations on the Yellow River from 1950 to 2014 indicated that, except for the Tangnaihai station in the head region, sharp downward trends existed in both the annual runoff and annual sedi-ment load according to the Mann–Kendal trend test;and their abrupt changes occurred in 1986 and in 1980, respectively, according to the rank sum test. Factors affecting the changes in the runoff and sediment load were very complicated. Results indicated that the reducing precipitation and the increasing water consumption were the main causes for the runoff decline, while the impoundment of the Longyangxia Reservoir and its combined operation with the Liujiaxia Reservoir exerted a direct bearing on the abrupt change in the annual runoff. In addition to the sediment load decrease associated with the runoff reduction, the reduced storm intensity, the conducted soil erosion control, and the constructed dam buildings all played an important role in the trends and abrupt changes of sediment load decline.  相似文献   

6.
Low-flow is widely regarded as the primary flow conditions for the anthropogenic and aquatic communities in most rivers, particularly in such an arid and semi-arid area as the Yellow River. This study presents a method integrating Mann–Kendall trend test, wavelet transform analysis and spatial mapping techniques to identify the temporal and spatial patterns of low-flow changes in the Yellow River (1955–2005). The results indicate that: (1) no trend can be identified in the major low-flow conditions in the upper Yellow River, but downward trends can be found in the middle and lower Yellow River; (2) similar periodic patterns are detected in the 7-day minima (AM7Q) in the upper and middle Yellow River, while different patterns are found in the lower Yellow River; (3) the increasing coefficients of variance in the primary low-flow conditions suggest that the variability of the low-flow is increasing from the upper to lower stream; (4) climate change and uneven temporal-spatial patterns of precipitation, jointly with highly intensified water resource utilization, are recognized as the major factors that led to the decrease of low-flow in the lower Yellow River in recent decades. The current investigation should be helpful for regional water resources management in the Yellow River basin, which is characterized by serious water shortage.  相似文献   

7.
气候变化和人类活动对流域径流影响的定量研究是当前研究的热点,赣江作为鄱阳湖流域最大的子流域,径流变化对鄱阳湖湿地水生态系统具有重要的影响.利用Mann-Kendall突变检验分析了赣江流域径流1955—2010年间演变趋势,再分别应用统计方法和IHACRES集总式模型分析气候要素和人类活动对径流的影响.研究表明IHACRES能够较好地模拟赣江流域径流,适用于中亚热带湿润季风气候区.Mann-Kendall突变检验表明赣江流域径流在1979年发生突变,可划分为1955—1979年和1980—2010年两个时段.降水是影响赣江流域径流年际变化的主要因素,而土地利用等人类活动的影响并不明显.水库建设显著影响赣江径流的季节分配,1980—2010年间人类活动影响更加显著,其中45%的年份秋季径流增加50%以上,26%的年份秋季径流增加超过100%,其中1989年的秋季径流增加幅度达到320%.  相似文献   

8.
D. Raje  P. Priya  R. Krishnan 《水文研究》2014,28(4):1874-1889
In climate‐change studies, a macroscale hydrologic model (MHM) operating over large scales can be an important tool in developing consistent hydrological variability estimates over large basins. MHMs, which can operate at coarse grid resolutions of about 1° latitude by longitude, have been used previously to study climate change impacts on the hydrology of continental scale or global river basins. They can provide a connection between global atmospheric models and water resource systems on large spatial scales and long timescales. In this study, the variable infiltration capacity (VIC) MHM is used to study large scale hydrologic impacts of climate change for Indian river basins. Large‐scale changes in runoff, evapotranspiration and soil moisture for India, as well as station‐scale changes in discharges for three major river basins with distinct climatic and geographic characteristics are examined in this study. Climate model projections for meteorological variables (precipitation, temperature and wind speed) from three general circulation models (GCMs) and three emissions scenarios are used to drive the VIC MHM. GCM projections are first interpolated to a 1° by 1° hydrologic model grid and then bias‐corrected using a quantile–quantile mapping. The VIC model is able to reproduce observed statistics for discharges in the Ganga, Narmada and Krishna basins reasonably well, even at the coarse grid resolution employed using a calibration period for years 1965–1970 and testing period from 1971–1973/1974. An increasing trend is projected for summer monsoon surface runoff, evapotranspiration and soil moisture in most central Indian river basins, whereas a decrease in runoff and soil moisture is projected for some regions in southern India, with important differences arising from GCM and scenario variability. Discharge statistics show increases in mid‐flow and low flow at Farakka station on Ganga River, increased high flows at Jamtara station upstream of Narmada, and increased high, mid‐flow and low flow for Vijayawada station on Krishna River in the future. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

9.
The annual hydrological regime of the Nakambe River shows substantial changes during the period 1955–1998 with a shift occurring around 1970. From 1970 to the mid-1990s, despite a reduction in rainfall and an increase in the number of dams in the basin, average runoff and maximum daily discharges increased. This paper reviews the hydrological behaviour of the Nakambe River from 1955 to 1998 and examines the potential role of land use change on soil water holding capacity (WHC) in producing the counter-intuitive change in runoff observed after 1970. We compare the results of two monthly hydrological models using different rainfall, potential evapotranspiration and WHC data sets. Model simulations with soil WHC values modified over time based upon historical maps of land use, are compared against simulations with a constant value for WHC. The extent of natural vegetation declined from 43 to 13% of the total basin area between 1965 and 1995, whilst the cultivated areas increased from 53 to 76% and the area of bare soil nearly tripled from 4 to 11%. The total reduction in WHC is estimated to range from 33 to 62% depending on the method used, either considering that the WHC values given by the FAO stand for the environmental situation in 1965 or before. There is a marked improvement in river flow simulation using the time-varying values of soil WHC. The paper ends with a discussion of the role of other factors such as surface runoff processes and groundwater trends in explaining the hydrological behaviour of the Nakambe River.  相似文献   

10.
In this paper we carry out a theoretical analysis based on the general one-dimensional morphodynamic model for rivers in order to show how the morphological equilibrium of a fiver is influenced by water and sediment diversion/supply along the river. The results of the analysis show that large scale water diversions, like those along the Lower Yellow River, can cause the development of a convex riverbed profile in the long-term. Deposition will take place along the whole reach of the river, with an increasing deposition depth from downstream to upstream. The slope of the river bed increases from upstream to downstream. Furthermore, an analysis on the morphological time scale shows that this development in the Lower Yellow River will take a time period on the order of decades to centuries. The results of the analysis have been compared with observations in the Lower Yellow River. Since the second half of the 1980＇s large scale water diversions from the Yellow River have been taking place. The observations show that this has indeed led to significant sedimentation along the river.  相似文献   

11.
The Yiluo River is the largest tributary for the middle and lower reaches of the Yellow River below Sanmenxia Dam. Changes of the hydrological processes in the Yiluo River basin, influenced by the climatic variability and human activities, can directly affect ecological integrity in the lower reach of the Yellow River. Understanding the impact of the climatic variability and human activities on the hydrological processes in the Yiluo River basin is especially important to maintain the ecosystem integrity and sustain the society development in the lower reach of the Yellow River basin. In this study, the temporal trends of annual precipitation, air temperature, reference evapotranspiration (ET0) and runoff during 1961–2000 in the Yiluo River basin were explored by the Mann‐Kendall method (M‐K method), Yamamoto method and linear fitted model. The impacts of the climatic variability and vegetation changes on the annual runoff were discussed by the empirical model and simple water balance model and their contribution to change of annual runoff have been estimated. Results indicated that (i) significant upwards trend for air temperature and significant downwards trend both for precipitation and ET0 were detected by the M‐K method at 95% confidence level. And the consistent trends were obtained by the linear fitted model; (ii) the abrupt change started from 1987 detected by the M‐K method and Yamamoto method, and so the annual runoff during 1961–2000 was divided into two periods: baseline period (1961–1986) and changeable period (1987–2000); and (iii) the vegetation changes were the main cause for change of annual runoff from baseline period to changeable period, and climatic variability contributed a little to the change of annual runoff of the Yiluo River. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

12.
荆江三口的分流对于洞庭湖区的水资源、河湖生态系统安全等均具有重要的影响.受到人类活动和气候变化双重影响,荆江三口分流发生显著变化,亟需明确其变化特征及适应性对策.基于实测数据分析了荆江三口径流变化特征,采用数值模拟评估了水库不同下泄方案对推迟荆江三口断流的影响.结果表明:荆江三口年径流量呈递减趋势,2003年以后分流比...  相似文献   

13.
Under the influence of all kinds of human activities, runoff decreased significantly in most river basins in China over the past decades. Assessing the effect of specific human activities on runoff is essential not only for understanding the mechanism of hydrological response in the catchment, but also for local water resources management. The Kuye River, the first-order tributary of the middle Yellow River, has experienced significant runoff declines. The coal resources are rich in the Kuye River Basin. In mined out area some cranny changed the hydrogeological conditions of the mining area and the hydrological process of the basin. In this study, the time series of runoff was divided into three periods at two critical years of 1979 and 1999 by precipitation–runoff double accumulation curve. The Yellow River Water Balance Model (YRWBM) is calibrated and verified to a baseline period in 1955–1978. Subsequently, natural runoff for human-induced period (1979 to 1998) and strongly human-induced period (1999 to 2010) is reconstructed using the YRWBM model. The YRWBM model performed well in simulating monthly discharges in the catchment, both Nash Sutcliffe coefficients in calibration and verification were above 70%, while relative errors in both periods were at less than 5%. The percentage of runoff reduction attributing to human activities was from 39.44% in 1979–1998 to 56.50% in 1999–2010. Further the influence of coal mining on river runoff was assessed quantitatively by YRWBM model simulation. The influence of coal mining on runoff reduction was 29.69 mm in 1999–2010 which was about 2.58 × 108 m3/a. It accounted for 71.13% of the runoff reduction during this period. Coal mining became a dominant factor causing the runoff reduction.  相似文献   

14.
The method of multiple regression is used to analyze the influences of flood events from the coarse sediment producing areas on the channel siltation and fluvial process of the lower Yellow River based on the flood events from 1950 to 1985. The results showed that the flood events from the coarse sediment producing areas carry larger amounts of sediment load and coarser particle sizes than from other source areas, which increases deposition in the lower river channel. And there exist good correlations between channel siltation of the lower reaches of the Yellow River and the coming water and sediment of flood events from the coarse sediment producing areas. Through these correlations, the amounts of sediment deposition in the lower river channel could be roughly estimated based on the runoff and sediment load of flood events from the coarse sediment producing areas. The sediment deposition caused the fluvial process. There exists a complex response of channel form change to the coming water and sediment load of flood events from the coarse sediment producing areas. When the sediment concentration is smaller than 200kg/m3, the ratio between wide-depth ratio after flood and wide-depth ratio before flood((B/h)a / (B/h)b) will increase with the increase of the maximum sediment concentration; when the sediment concentration is near 200kg/m3, (B/h)a / (B/h)b reaches the maximum value; and when the sediment concentration reaches the limits of hyperconcentrated flow, (B/h)a / (B/h)b will decrease with the increase of the maximum sediment concentration. Generally, flood events from the coarse sediment producing areas made channel form of the lower Yellow River deeper and narrower, but a large amount of sediment deposition simultaneously occurs. So, the impacts of flood events from the coarse sediment producing areas on the channel of the lower Yellow River are lessened.  相似文献   

15.
Abstract

The water shortage in the Yellow River, China, has been aggravated by rapid population growth and global climate changes. To identify the characteristics of streamflow change in the Yellow River, approximately 50 years of natural and observed streamflow data from 23 hydrological stations were examined. The Mann-Kendall and Pettitt tests were used to detect trends and abrupt change points. The results show that both the natural and the observed streamflow in the Yellow River basin present downward trends from 1956 to 2008, and the decreasing rate of observed streamflow is generally faster than that of the natural streamflow. Larger drainage areas have higher declining rates, and the declining trends are intensified downstream within the mainstream. The possibility of abrupt changes in observed streamflow is higher than in natural streamflow, and streamflow series in the mainstream are more likely to change abruptly than those in the tributaries. In the mainstream, all the significant abrupt changes appear in the middle and latter half of the 1980s, but the abrupt changes occur somewhat earlier for observed streamflow than for natural streamflow. The significant abrupt change for the observed streamflow in the tributaries is almost isochronous with the natural streamflow and occurs from the 1970s to 1990s. It is implied that the slight reduction in precipitation is not the only direct reason for the streamflow variation. Other than the effects of climate change, land-use and land-cover changes are the main reasons for the natural streamflow change. Therefore, the increasing net water diversion by humans is responsible for the observed streamflow change. It is estimated that the influence of human activity on the declining streamflow is enhanced over time.

Editor Z.W. Kundzewicz

Citation Miao, C.Y., Shi, W., Chen, X.H., and Yang, L., 2012 Miao, C.Y., Yang, L. and Chen, X.H. 2012. The vegetation cover dynamics (1982–2006) in different erosion regions of the Yellow River basin, China. Land Degradation and Development, 23(1): 62–71. [Crossref], [Web of Science ®] , [Google Scholar]. Spatio-temporal variability of streamflow in the Yellow River: possible causes and implications. Hydrological Sciences Journal, 57 (7), 1355–1367.  相似文献   

16.
夏季风期间长江流域的水汽输送状态及其年际变化   总被引：3，自引：1，他引：2       下载免费PDF全文
本文利用NCEP/NCAR再分析资料,分析了长江流域夏季风期间的水汽收支和循环,着重研究了不同月份与水汽收支的年际变化显著相关的大尺度水汽输送和环流异常.流域范围的西南夏季风水汽输送以6、7月最为强烈,经向输送在5～8月造成流域水汽辐合,9月造成辐散;纬向输送在5～7月造成流域水汽辐散,8、9月造成辐合.研究表明,在不同月份,流域的南北边界处的水汽输送在流域水汽收支的年际变化中起着不同的作用.这种变化与大气环流的异常密切相关.在夏季风相对较弱月份（5、8、9月）,流域水汽收支的年际变化极大地受到流域南边界南风水汽输入通道的影响,对应于水汽收入偏丰年,该3个月500 hPa高空在青藏高原东部都存在显著异常低压区,而且,8、9月在中南半岛及其以东洋面存在显著异常反气旋环流,与8月西太副高的向西向南异常伸展,以及9月副高的西伸较弱和南北范围较宽有关,这些异常环流均造成南边界的大量异常水汽输入.而在夏季风十分强盛的6、7月,流域北边界南风水汽输出极大增加,成为流域水汽收入年际变化的关键敏感通道,对应于水汽收入偏丰年,6月500 hPa高空主要受中纬度以黄海和东海为中心的异常低压系统和气旋性异常环流影响,与该区域副高偏南、偏弱有关,而7月则主要受中高纬以外兴安岭为中心的异常高压和反气旋性异常环流影响,应该是由于该区域大陆高压的频繁生成造成的,它们均造成流域北边界水汽输出的异常减少.  相似文献   

17.
李彦彦  李冰  杨桂山  万荣荣 《湖泊科学》2021,33(6):1885-1897
河湖水文连通性强弱对于维系流域水资源安全、河湖生态系统稳定等方面具有重要意义.本文首先利用1960-2019年松滋口新江口与沙道观两站与干流枝城站实测水文资料以及河道典型横断面地形资料,采用Mann-Kendall法与趋势线法分析讨论枯水期松滋口分流变化的特征与诱因,然后,针对枯水期松滋口河道的分流问题提出河道治理方案.结果表明：松滋口枯水期的流量主要来自西支.在1960-2019年间,枯水期西支分流量呈现三峡大坝蓄水运行前后从下降趋势转变为显著上升趋势,而东支分流量在下荆江裁弯后至今基本处于断流状态,下荆江裁弯、葛洲坝运行及三峡大坝蓄水运行是其分流量变化的主要诱因.根据建立分流量与水位差（干流水位与河底高程）的回归关系,模拟出在松滋口西东支现有河道的基础上,河床高程分别下降1 m与2.5 m左右,其分流量可达到或接近1960s分流量水平,有助于缓解区域水资源与环境生态问题.  相似文献   

18.
I.INTRODUCTIONTwo-dimensionalnumericalmodelisaPOwerfoltoolforengineersandriVermanagerstopredictfloodhydxaulics,identifyareasofinundation,anddesignoptionsforfloodcontrollingstructures.SomespecialproblemswithheavilysedimentladenflowriVershouldbecarefullyconsideredforthenumericalmodeldesigning;1.theplaneformofariVerisusuallybraidedanditsmainchannelshiftsoften.Themainchannelandbarreplaceeachotherseveraltimesinonefloodevent.Atagivenlocationthewaterdepthmaychangefromover10meterstoseveralcenhm…  相似文献   

19.
ABSTRACT

Under the combined influence of climate changes and human activities, the hydrological regime of the Wei River shows remarkable variations which have caused many issues in the Wei River in recent decades, such as a lack of freshwater, water pollution, disastrous flooding and channel sedimentation. Hence, hydrological regime changes and potential human-induced impacts have been drawing increasing attention from local government and hydrologists. This study investigates hydrological regime changes in the natural and measured runoff series at four hydrological stations on the main Wei River and quantifies features of their long-term change by analysing their historical annual and seasonal runoff data using several approaches, i.e., continuous wavelet transform, cross-wavelet, wavelet coherence, trend-free pre-whitening Mann-Kendall test and detrended fluctuation analysis. By contrasting two different analysis results between natural and measured river runoff series, the impacts of human activities on the long-term hydrological regime were investigated via the changes of spatio-temporal distribution in dominant periods, the trends and long-range memory of river runoff. The results show : (a) that periodic properties of the streamflow changes are the result of climate, referring to precipitation changes in particular, while human activities play a minor role; (b) a significant decreasing trend can be observed in the natural streamflow series along the entire main stream of the Wei River and the more serious decrease emerging in measured flow should result from human-induced influences in recent decades; and (c) continuous decreasing streamflow in the Wei River will trigger serious shortages of freshwater in the future, which may challenge the sustainability and safety of water resources development in the river basin, and should be paid great attention before 2020.
Editor Z.W. Kundzewicz; Associate editor K. Hamed  相似文献   

20.
The hydrological regime, morphological structure, and landscapes of the Indus River delta are considered, and the significant changes that took place in them during the second half of the XX century because of the large-scale hydraulic engineering activity in the river’s basin, runoff regulation, and water withdrawal for irrigation are analyzed. It is shown that the abrupt decrease in water and sediment runoff in the Indus have affected the hydrological processes in the river’s lower reaches and caused delta degradation.  相似文献   

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