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Quantifying the actual sediment load flux into Lake Baikal:A case study of the main tributary——The Selenga River(Russia)

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International Journal of sediment Research 2022年第2期37卷 238-247页

作者： Tatiana Potemkina Vladimir Potemkin Limnological Institute of the Siberian Branch of Russian Academy of Sciences

The significant reduction of sediment load flux into Lake Baikal from its main tributary-the Selenga River began in the mid-1970 s,and can be explained by climate change and socio-economic activities.Integrated analysis was done of changes in hydro-meteorological parameters(water discharge,sediment load,air temperature,and precipitation) and their tendencies over periods of 1946-1975(baseline) and1976-2017(warming).Changes in natural processes and human activity were negligible during the baseline period.In the warming period,against the background of an increase in temperature,the water discharge had a slight decreasing trend(-13%) whereas the sediment load has significantly decreased(-53%) these are consist with the precipitation change(-9.4%).Analysis of hydro-climatic data using statistical methods showed that in the warming period the greatest reduction in river sediment runoff occurred in the interval 1996-2017.In this period the sediment load was 768 × 10～3 t/yr,which is less than the average value during the warming period-1048 × 10～3 t/yr.Considering sedimentation in the Selenga River delta,the actual sediment load flux from the Selenga River into Lake Baikal amounted to 515 × 10～3 t/yr,which is three times less than the average multiyear value 1535 × 10～3 t/yr for observation period(1946-2017).

关键词： sediment load Climate change Human activity Selenga River Lake Baikal

Joint probability analysis of water and sediment and predicting sediment load based on copula function

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International Journal of sediment Research 2022年第5期37卷 639-652页

作者： Haoyu Jin Xiaohong Chen Ruida Zhong Yingjie Pan Tongtiegang Zhao Zhiyong Liu Xinjun Tu School of Civil Engineering Sun Yat-sen University Guangdong Engineering Technology Research Center of Water Security Regulation and Control for Southern China Sun Yat-sen University Key Laboratory of Water Cycle and Water Security in Southern China of Guangdong High Education Institute Sun Yat-sen University Dongjiang Water Source Project Management Division of Shenzhen

The Jinsha River comprises the upper reaches of the Yangtze River, which is the river section with the highest sediment content. Monitoring of sediment transport in the Jinsha River is done to the guarantee for the normal operation of the Three Gorges Reservoir. In the current study, a copula function was used to do a joint probability analysis of the water and sediment in the Jinsha River Basin(JRB), further a sediment load prediction model based on the copula function also was constructed. The results show that the average annual flow from 2001 to 2018 at the outlet of the Jinsha River(Yibin station) is about60.43 billion m3, and the average annual sediment load is about 58.82 million t. The linear correlation coefficient between annual flow and annual sediment load is 0.28. The best marginal distribution for annual flow and sediment load is Pearson Type Three(PE3) and Generalized Normal(GNO), respectively,and the best fit for the combined distribution of the two variables is the Frank copula function. The synchronous probability of water and sediment occurrence is 0.459, and the asynchronous probability is0.541. Based on the copula prediction model, the sediment load can be effectively simulated, and the correlation coefficient between the simulated sequence and the measured sequence reached 0.93. The current study provides important significance for the analysis of water and sediment in the JRB, which is beneficial to the management of Three Gorges Reservoir sediment discharge in the upstream and downstream.

关键词： Marginal distribution Joint distribution Copula Flow sediment load Jinsha River Basin (JRB)

sediment load reduction in Chinese rivers

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International Journal of sediment Research 2008年第1期23卷 44-55页

作者： Cheng LIU1, Jueyi SUI2, and Zhao-Yin WANG31 Prof., Dr., International Research and Training Center on Erosion and sedimentation, Beijing, 100044, China, 2 Associate Professor, Environmental Engineering Program, University of Northern British Columbia, Prince George, BC, Canada 3 Prof., Dr., Dept. of Hydraulic Engineering, Tsinghua University, Beijing, 100084, China Prof. Dr. International Research and Training Center on Erosion and Sedimentation Beijing 100044 China Associate Professor Environmental Engineering Program University of Northern British Columbia Prince George BC Canada Prof. Dr. Dept. of Hydraulic Engineering Tsinghua University Beijing 100084 China

In this paper, the changes in the annual runoff and sediment transport have been assessed by using the long term observation data from 10 gauging stations on 10 large rivers across China from far north to far south. It is found that the annual sediment yield has generally had a decreasing trend in the past half century. According to the changes in annual runoff and the sediment yield per area, rivers in China can be classified into the following three groups: 1) rivers with decreasing annual sediment transport and stable runoff; 2) rivers with both decreasing annual sediment transport and runoff and 3) rivers with greatly reduced annual sediment transport and decreasing annual runoff. The results indicate that, in all southern rivers (to the south of the Huaihe River including the Huaihe River), there has been little change in average annual runoff but a dramatic decrease in annual sediment transport. In the northern rivers, however, both the annual sediment yield and the runoff show significant evidence of reduction. To further investigate the recent changes in annual runoff and sediment transport, the short-term observation data from these 10 gauging stations in the recent 10 years have been assessed. Results show that both the annual sediment transport and the runoff have decreased significantly in the northern rivers in the past 10 years. Using the Yellow River at the Lijin Station as an example, the average annual runoff for the last 10 years is only 1/3 of the long term average value and the average annual sediment yield of the last 10 years is only 1/4 of the long term average value. More unusually, in the Yongding River the annual sediment yield has approached zero and the runoff has decreased significantly. In addition, the impacts of human activities on the changes in both runoff and sediment transport have been discussed.

关键词： China Runoff sediment load Large rivers sediment yield Yangtze River Yellow River

Multi-scale variability of water discharge and sediment load into the Bohai Sea from 1950 to 2011

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Journal of Geographical Sciences 2015年第1期25卷 85-100页

作者： REN Huiru LI Guosheng CUI Linlin HE Lei Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

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.

关键词： water discharge sediment load resonance periods abrupt changes multi-scale periods Yellow River Bohai Sea

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Copula-based identification of the non-stationarity of the relation between runoff and sediment load

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International Journal of sediment Research 2017年第2期32卷 221-230页

作者： Shengzhi Huang Pei Li Qiang Huang Guoyong Leng State Key Laboratory Base of Eco-Hydraulic Engineering in Arid Area Xi'an University of Technology Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences

It is important to identify the non-stationarity in the relation between runoff and sediment load under the backdrop of the changing environment.This relation helps to further understand the mechanisms of runoff and sediment yield.A copula-based method was used to detect possible change points in the relation between runoff and sediment load in the Wei River Basin(WRB),China,where soil erosion is a very severe issue.The modified Mann-Kendall trend test method was applied to obtain the trends of runoff and sediment load spanning 1960-2010 at monthly and annual timescales.Finally,the causes of the identified non-stationarity of the relation between runoff and sediment load were roughly analyzed from the perspective of climate change and human activities.Results indicated that:(1)the runoff and sediment load in the Jinghe and Wei rivers were generally characterized by noticeably decreasing trends at both monthly and annual timescales;(2)both the Jinghe and Wei rivers had a common change point(2002),implying that the stationarity of the relation between runoff and sediment load in the Jinghe and Wei River was invalid;(3)human activities including increasing water consumption and growing application of soil conservation practices are dominant factors resulting in non-stationarity in the relation between runoff and sediment load in the WRB.This study provides a new idea for identifying the non-stationarity of multivariate relation in the hydro-meteorological field under the background of the changing environment.

关键词： Copula-based method Runoff sediment load Non-stationarity Change point Human activities

Changes in runoff and sediment load from major Chinese rivers to the Pacific Ocean over the period 1955-2010

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International Journal of sediment Research 2013年第4期28卷 486-495页

作者： Cheng LIU Jueyi SUI Yun HE Faye HIRSHFIELD International Research and Training Center on Erosion and sedimentation Environmental Engineering Program University of Northern British Columbia China Institute of Water Resources and Hydropower Research University of Northern British Columbia

Changes in runoff and sediment loads to the Pacific Ocean from 10 major Chinese rivers are presented in this paper.To quantitatively assess trends in runoff and sediment loads,a parameter called the "Trend Ratio 7"" has been defined in this paper.To summarize total runoff and sediment load from these rivers,data from 17 gauging stations for the duration 1955 to 2010 has been standardized,and the missing data have been interpolated by different approaches according to specific conditions.Over the observed 56-year study period,there is a quite stable change in total runoff.Results show that the mean annual runoff flux entering the Pacific Ocean from these rivers is approximately 1,425billion cubic meters.It is found that all northern rivers within semi-arid and transitional zones including the Songhua,Liaohe,Haihe,Yellow and Huaihe rivers present declining trends in water discharge.Annual runoff in all southern rivers within humid zones including the Yangtze,Qiantang,Minjiang,Pearl and Lancang rivers docs not change much,except for the Qiantang River whose annual runoff slightly increases.The annual sediment loads of all rivers show significant declining trends;the exceptions are the Songhua and Lancang rivers whose annual sediment loads have increasing trends.However,the mean annual sediment flux carried into the Pacific Ocean decreased from 2,026million tonnes to 499 million tonnes over the 56-ycar period.During this time there were 4 distinct decreasing phases.The decrease in annual sediment flux is due to the integrated effects of human activity and climate change.The reduction in sediment flux makes it easy for reservoir operation;however,the decrease in sediment flux also creates problems,such as channel erosion,river bank collapse and the retreat of the delta area.

关键词： Runoff sediment load Pacific Ocean Yellow River Yangtze River

Analyses of trends and causes for variations in runoff and sediment load of the Yellow River

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International Journal of sediment Research 2017年第2期32卷 171-179页

作者： Hongling Shi Chunhong Hu Yangui Wang Cheng Liu Huimei Li State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research International Research and Training Center on Erosion and sedimentation

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 sediment load according to the Mann-Kendal trend test;and their abrupt changes occurred in 1986 and in1980,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.

关键词： Yellow River Runoff sediment load Variation trends

Erosion Rates in Dam Catchments in Jordan—Effects of Topography, Geology, and Urbanizations

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Open Journal of Soil Science 2024年第5期14卷 319-331页

作者： Elias Salameh Hakam Al-Alami Ibraheem Hamdan Department of Geology University of Jordan Amman Amman Jordan Faculty of Earth and Environmental Sciences Department of Applied Earth and Environmental Sciences Al al-Bayt University Mafraq Jordan Environment Water and Energy Research Center Al al-Bayt University Mafraq Jordan

Erosion as a natural process produces soils, which are very important natural resources for the fest land plant- and animal kingdoms. Loss of the soil cover reduces agricultural production, biodiversity, and the role of soil as a filter for infiltrating water to replenish the groundwater. It also threatens the food supplies. The knowledge of erosion rates of rocks and terrains is important for developing proactive measures to protect soils from erosion and loss. In this study, erosion rates of catchment areas were calculated based on dams’ catchment extensions and the sediment loads transported by flood flows into dams’ lakes. The study results show that the chemically, via floodwater, transported quantities of materials are negligible compared to the solid materials transported by the water. It calculates erosion rates ranging from 0.013 to 0.212 mm/yr (13 - 212 m/106 yr) for the different catchment areas. Erosion rates in Jordan are, generally, higher than those calculated for the different parts of the world ranging from 2.5 to 60 m/106 yr. This fact can be explained by the very steep topography, calcareous rock cover of the catchment areas and the barren rock exposures.

关键词： Erosion Rates Jordan Dams sediment load

sediment load in Runoff Under Laboratory and Field Simulated Rainfall

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Agricultural Sciences in China 2004年第1期3卷 31-36页

作者： JINKe WouterSchiettecatte KoenVerbist DonaldGabriels RogerHartmann CAIDian-xiong SoilandFertilizerInstitute ChineseAcademyofAgriculturalSciencesBeijing100081P.R.China DepartmentofSoilManagementandSoilCare GhentUniversity9000GentBelgium

Soil erosion is one of the most important problems in the Loess Plateau of China affectingsustainable agriculture. Near Luoyang (Henan Province, China), field plots were constructed tomeasure soil erosion rates under conventional tillage practices using field-simulated rainfall.Field rainfall experiments were carried out to compare previous results from laboratoryrainfall simulations on the same soil for interrill conditions. Although in the laboratoryexperiments, a strong correlation was found between the stream power of the runoff water andthe unit sediment load, this sediment transport equation overestimated the field rainfallsimulation results. Another sediment transport equation derived by Nearing et al. for rillerosion was in better agreement with the results of the field experiments, although it alsooverestimated these values. The measured sediment load values during the field rainfallsimulations were also lower than those found during field experiments on the same soil but witha loosened surface layer. This difference indicates the importance of soil physical conditionof surfce like soil structure and aggregate size, which may contribute to the discrepancybetween the field and laboratory experiment results.

关键词： Stream power Runoff sediment load Rainfall simulation

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