Search

The cooperative operation of cascade reservoir systems is an efficient way to regulate water resources. However, noncooperation among various reservoir stakeholders is often observed in practice; this produces an interesting dilemma in the game of water resource management. Considering the upper Yellow River cascade reservoir system as a case study, in this paper we model and analyze the cooperation dilemma in a cascade reservoir system. In our game theoretical analysis, we find that, except for the most upstream reservoir, all reservoirs have free-ride strategies. The free-ride strategy indicates that a reservoir obtains free gain from the cooperation of other reservoirs due to spatial connections, and this fact changes the cooperative game in terms of equilibrium and benefit allocation. The results show that the regulation capacity of the free rider directly affects the equilibrium and benefit allocation of the game. A midstream reservoir with a small or medium regulation capacity tends to employ a free-ride strategy. A midstream reservoir with a large regulation capacity can entirely interrupt the cooperation between upstream and downstream reservoirs, interestingly, which can lead to the disappearance of the free-ride strategy for the midstream reservoir. However, the downstream reservoir may employ a free-ride strategy when the midstream reservoir chooses to cooperate. This implies that grand cooperation is not stable when considering free-ride, whereas partial coalitions are more likely to form. In this paper, we derive equilibrium in the cooperative game of cascade reservoirs, providing theoretical interpretation of the noncooperation phenomenon in the operation of cascade reservoirs. [ABSTRACT FROM AUTHOR]

Accurately identifying the matching relationships between territorial space evolution and the resources and environment carrying capacity will directly guide the sustainable use of territorial space. Based on the evaluation of the territorial space dynamics of the lower Yellow River, this paper evaluates the suitability of territorial space development by focusing on ecological protection, agricultural development, and urban construction. Specifically, the resources and environment carrying capacity is estimated by identifying and mediating potential conflicts in the development of territorial space. The matching relationship between the evolution of territorial space and the resources and environment carrying capacity is identified using the matching degree model. The results demonstrated that: (1) Between 2000 and 2020, the agricultural space of the lower Yellow River was relatively stable, while the ecological space was generally shrinking, and the urban space continued to increase; (2) The characteristics of suitability for the agricultural development and urban construction of the lower Yellow River are characterized by landform and land-sea differentiation. The carrying scale of resources and the environment is based on agricultural space and is increasing yearly, followed by ecological space, which is gradually decreasing, and urban space, which first increased and then decreased; (3) Between 2000 and 2020, the matching index of the ecological and agricultural space evolution and the resource and environmental carrying capacity in the lower Yellow River exhibited a downward trend, while the regional difference increased. Furthermore, the matching index of urban space and the resources and environment carrying capacity indicated an upward trend, while the regional difference decreased. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper refers to a survey conducted in Zhengzhou section of the Yellow River for the purpose of investigating heavy metal pollution characteristics and of exploring the pollution sources. Monitoring was thereby carried on August 29-31, 2022 along the riparian zone collecting samples of the river sediments and analyzing the concentrations of nine kinds of heavy metal, including Cd, Pb, Cu, Zn, As, Hg, Cr, Ni and Mn. Then the Tessier five-step sequential extraction method was used for the morphological analysis of the heavy metals; the ground accumulation index (Igeo) was used to evaluate heavy-metal pollution degree, with Nemero pollution index being applied to the comprehensive assessment of the pollution situation; and the principal component analysis (PCA) and absolute factor analysis-multiple linear regression analysis model (APCS-MLR) were used to analyze the source of the pollutants. Consequently, the survey showed that both of the mean concentrations of Pb and Cd in the sediments of the riverine zone of Zhengzhou section of the Yellow River exceeded the soil background value of heavy-metal in Henan Province. Results of the speciation analysis showed that the environmental activities of Mn, Cd, Pb and Hg were relatively high; the evaluation of geo-accumulation index (Igeo) indicated that Cd had resulted in slight to moderate pollution in the sediments of the River; and the evaluation results of the Nemero pollution index showed that all the above-mentioned heavy-metal elements were on the safety level. Result of the source apportionment suggested that tannery industry, agricultural activities and automobile parts production, as well as the natural source were the major heavy-metal pollution sources in the riparian zone of Zhengzhou section of the Yellow River. [ABSTRACT FROM AUTHOR]

Accurate and reliable monthly streamflow prediction plays a crucial role in the scientific allocation and efficient utilization of water resources. In this paper, we proposed a prediction framework that integrates the input variable selection method and Long Short-Term Memory (LSTM). The input selection methods, including autocorrelation function (ACF), partial autocorrelation function (PACF), and time lag cross-correlation (TLCC), were used to analyze the lagged time between variables. Then, the performance of the LSTM model was compared with three other traditional methods. The framework was used to predict monthly streamflow at the Jimai, Maqu, and Tangnaihai stations in the source area of the Yellow River. The results indicated that grid search and cross-validation can improve the efficiency of determining model parameters. The models incorporating ACF, PACF, and TLCC with lagged time are evidently superior to the models using the current variable as the model inputs. Furthermore, the LSTM model, which considers the lagged time, demonstrated better performance in predicting monthly streamflow. The coefficient of determination (R2) improved by an average of 17.46%, 33.94%, and 15.29% for each station, respectively. The integrated framework shows promise in enhancing the accuracy of monthly streamflow prediction, thereby aiding in strategic decision-making for water resources management. [ABSTRACT FROM AUTHOR]

Copyright of Advances in Water Science / Shuikexue Jinzhan is the property of Editorial Board of Advances in Water Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

China has implemented many green transition policies to reach its carbon peak target, some of which do not consider the actual carbon reduction pressures that localities can afford, thus lowering the living standards of residents and economic growth, which makes the green transition process unsustainable. The Yellow River Basin plays an important role in China's energy, food, manufacturing, and ecological sectors. Thus, the design of green transition policies in the region needs to be modest and efficient. Based on the data of 100 prefecture-level cities in the Yellow River Basin from 2006 to 2017, this paper uses the K-means clustering to divide the carbon reduction potential of cities into four types. Most cities' carbon reduction potentials are low or medium, unsuitable for adopting a rapid green transition. Based on the logarithmic mean Divisia index (LMDI) decomposition results and the carbon reduction potential, we designed different carbon-control pathways: Shandong and Henan should focus on increasing investment in green technology, especially oxy-combustion technology; Gansu, Ningxia, and Qinghai could partially offset carbon emissions through land use, land-use change and forestry (LULUCF) activities; Sichuan and Inner Mongolia should increase their energy-use efficiency; Shaanxi and Shanxi could use green finance to complete the upgrading of local industries. The above emission-reduction strategies can be actively pursued in cities with high emission reduction potential and should be implemented with caution in cities with low emission reduction potential. This paper provides a new and cost-effective perspective on carbon emission control in the Yellow River Basin. [ABSTRACT FROM AUTHOR]

The governance and development history of the Yellow River is an important part of Chinese history. Many historical documents and archives have been produced around the governance and development of the Yellow River as well as modern information resources such as databases and pictures, which together constitute a special collection of cultural heritage resources of the Yellow River Governance Landscape. In this paper, a literature search was conducted and unique resources collected for the construction of the Yellow River Governance Landscape, including the main literature, archives, pictures, databases, and other resources. Experts identified the concept and relevant resources of the Yellow River Governance Landscape, and librarians constructed the special collection. The future direction of digitization and database construction for the Yellow River Governance Landscape resources are also discussed. The special resources of the Yellow River Governance Landscape will help to increase the discipline collections and special collections of university libraries, provide resources for multidisciplinary teaching and research, and help to digitize and build databases of Yellow River Governance Landscape resources in the future as well as provide the content basis for open access and sharing of digital resources. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Many rivers are tightly coupled and intersected with aeolian sand dunes, whose geomorphological evolution involves not only fluvial processes but also aeolian processes that pose a new challenge to fluvial geomorphological studies. However, due to few field studies, our overall understanding of the desert channel geomorphic process is limited. In this paper, we present an outstanding example of desert river channel evolution regulated by aeolian–fluvial interactions in the Ulan Buh Desert of the Yellow River, based on a long time series data set (1966–2019) of channel cross-sections. The results indicate that the lateral addition of aeolian sand, the water–sediment relationship and human interference have a significant role at different periods of channel evolution. Before 1986, higher discharge, lower sediment content and greater intensity of aeolian activity caused aeolian–fluvial interactions and a relative scouring and silting balance in the channel, with little human activity. From 1986 to 2000, an increase in large reservoir operation, vegetation coverage and floodplain farming, coupled with water–sediment relationship variation, caused rapid deposition and shrinkage of the river channel. From 2000 to 2014, the channel kept a slight scouring state. With Haibowan reservoir operation beginning in 2014, the talweg experienced rapid scouring and undercut rebound. However, an expanding and stable floodplain accelerated sedimentation on the floodplain and weakened river lateral erosion, indicating that the channel has shown a shrinkage trend. Meanwhile, wavelet analysis results indicate that human interferences and aeolian activities have no significant role in the periodical characteristics of the channel's longitudinal erosion and deposition. Therefore, on the whole, increasing human interferences and decreasing wind dynamics have driven this desert wandering channel to be stable, and to gradually form a new balance between erosion and sedimentation. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sediment erosion through synergetic effects between free surface vortex (FSV) and particle erosion in silt-laden flow seriously affects the safe operations of pump. The purpose of this paper is to study the influence of free surface vortex entrainment on the erosion inner the pump impeller, aimed at the FSV and sediment erosion in sediment laden flow in a pump station of Yellow River, a new Eulerian-Lagrange approach was applied to simulate the sediment-laden flow by combining the Lagrange particle tracking approach and Volume of Fluid (VOF) method, followed by the application of Tabakoff model to estimate the erosion. Volume of fluid method was used to simulate the continuous flow FSV, and Lagrange method the particle trajectory. The theoretical model and filed results on site were used to verify the reliability of the proposed approach. Free surface vortex on particle motion and microscopic interactions between air and erosion were reviewed and discussed. Combined with the theoretical analysis and calculation results, the particle impact angle in the impeller was analyzed, and the erosion types were defined. Air entrainment by FSV does not directly erode the impeller components, but mainly changes the position, the local velocity and the concentration of the particles, which aggravates the sediment erosion in the impeller. Interestingly, air entrainment can reduce the surface erosion at some instantaneous moments. The present work may provide important engineering insights to resolve the erosion. [ABSTRACT FROM AUTHOR]

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problem of sediment accumulation in the diversion canal, which adversely affects the water supply system, this paper designs a diversion and sand discharge system at the head of the canal to improve the efficiency of water use. According to the measured data of a section of the Yellow River Ningxia, a two-dimensional numerical simulation is used to construct a two-dimensional hydrodynamic model and a sediment model based on MIKE 21 for a section of the Yellow River Ningxia to simulate the water diversion at the head of the canal under two different working conditions. The results of the study show that the diversion channel changes the equilibrium of the hydrodynamic elements of the river, direct diversion canal (case 1) flow dynamics axis has oscillated 46.6m towards the concave bank, the average sand content of the channel is 0.6 kg/m³ and the maximum sand content is 0.89 kg/m³; the axis of flow dynamics in the sand reduction diversion channel (case 2) has oscillated 62.6 m towards the concave bank, the flow velocity at the head of the channel is in the range of 0.2~0.4 m/s, the average sand content of the channel is 0.2 kg/m³ and the maximum sand content is 0.6 kg/m³. Therefore, the design of the head of case 2 can improve the sediment deposition problem of the diversion canal and enhance the durability of the water intake system. [ABSTRACT FROM AUTHOR]

In 2020, Yellow River runoff was more than twice as much as past years, and the proportion of strong winds was also higher than that in past years, which will inevitably lead to a change in salinity plume distribution in the Yellow River Estuary and Laizhou Bay. Based on FVCOM numerical modelling, this paper presents the spatial salinity distribution and dispersion of the Yellow River Estuary and Laizhou Bay during the wet and dry seasons in 2020. We used data from six tidal and current stations and two salinity stations to verify the model, and the results showed that the model can simulate the local hydrodynamic and salinity distribution well. The influence of river discharge and wind speed on salinity diffusion was then investigated. The simulation results showed that under the action of residual currents, fresh water from the Yellow River spread to Laizhou Bay, and the low salinity area of Laizhou Bay was mainly distributed in the northwest. The envelope area of 27 psu isohaline can account for about one-quarter of Laizhou Bay in the wet season, while the low-salinity area was only concentrated near the estuary of Yellow River in the dry season. River discharge mainly affects the diffusion area and depth of fresh water, and wind can change the diffusion structure and direction. In the wet season, with the increase in wind speed, the surface area of the plume decreased gradually, and the direction of the fresh water plume changed counterclockwise from south to north. During the dry season, the plume spread to the northwest along the nearshore. The increase in wind speed in the early stage increased the surface plume area, and the plume area decreased above a wind speed of 10 m/s due to the change in the turbulence structure. The model developed and the results from this study provide valuable information for establishing robust water resource regulations for the Yellow River. This is particularly important to ensure that the areas with low salinity in the Yellow River Estuary will not decrease and affect the reproduction of fish species. [ABSTRACT FROM AUTHOR]

This is a paper about the speed and intensity with which new and intensive human land use in a semi-arid environment can bring about large-scale environmental change. In particular, this paper pinpoints how and why it was that the Yellow River shifted from a long-term condition of relative stability to a later state of frequent floods and course changes in the eleventh century. It is possible to trace the environmental history of this dramatic and sudden change of state with precision and confidence. Historical sources that record the dates and characteristics of flood events downstream align well with those that note the locations and dates of human activity upstream. More important, each aligns well not only with one another, but also with information from environmental science: sediment cores that preserve soil and pollen evidence for the timing and processes of systematic change. [ABSTRACT FROM AUTHOR]

The ongoing transition from fossil fuel-based electricity generation toward green energy relying on the intermittent renewable energy sources indispensably requires development of novel energy conversion and storage methods. Depending on a particular location and local resources, pumped storage, lithium- or sodium-ion batteries, compressed air energy storage, as well as the so called power-to-gas (P2G) technologies may be applied. Taking into account the abundant solar energy resources available in the northwestern China, such as Ningxia hui autonomous region, and local water resources coming from the Yellow River, a power-to-hydrogen (P2H2) distributed energy conversion system is proposed in this paper, which is based on a high-efficiency reversible Solid Oxide Cell (rSOC). The conducted studies comprise tests with simulated current based on the actual photovoltaic power station data, and with usage of the as-obtained Yellow River water for the electrolysis mode without any pretreatment. It is documented that the reversible operation is beneficial, and the tested cell can operate for a prolonged time. Of importance, Na, Ca, Mg, and Si elements remain in an evaporator, and do not contaminate the cell, while higher than the initial boron concentration can be found in the condensed exhaust gases. The respective operational parameters of the system correspond to an electrolysis current density loading up 433.3 mA cm−2 for 4 h, as well as fuel cell operation mode with a current density of 8.3 mA cm−2 for 12 h. It is found that the average voltage losses in the electrolysis cell and fuel cell mode are 0.27 %/cycle and 0.886 %/cycle, respectively, indicating that the lifetime of the cells can be more than 800 h. The reported studies demonstrate validity of applying rSOC-based P2H2 system, especially if abundant photovoltaic power and water resources are available. [Display omitted] • The Yellow River water was utilized by rSOC for the first time. • The designed test current was modeled with local photovoltaics. • The P2H2 nearby consumption system can reversibly operate for over 800 h. • The degradation rates in SOFC mode are lower than those in SOEC mode. • The Yellow River water has no significant effect on the degradation rate. [ABSTRACT FROM AUTHOR]

In order to expedite the transition of the Yellow River Simulator into the operational phase and quickly make use of its positive role in the difficulties of water resources shortage, economic imbalance and ecological fragility in the Yellow River Basin, an intelligent calculation method system for the Yellow River Simulator had been thoroughly sorted out and implemented. Drawing upon the concept of intelligent computing, the vital importance of the Yellow River Simulator’s intelligent computing was articulated from the perspectives of data storage and preprocessing, simulation computing power, and swift responsiveness, as well as its significance in ecological conservation and management, efficient water resources utilization and disaster evaluation and mitigation. Based on the architectural framework of the Yellow River Simulator, four branches of intelligent computing methods, namely biomimetic intelligent computing, machine learning, fuzzy computing and intelligent computation were summarized in detail. Envisioning the transformative potential of intelligent computation methodologies for the Yellow River Simulator, this paper explored its huge application prospects in development planning, disaster management and resources allocation. [ABSTRACT FROM AUTHOR]

Since 1950 s, the planning of Heishanxia reach of the Yellow River has been nearly 70 years old. In the long-term demonstration process, relevant departments and local governments put forward a number of different development schemes according to the situation and research results in different periods. In view of the different viewpoints of different subjects on the functional orientation and development scheme of the river reach, no decision has been made so far. This paper reviewed the main planning demonstration process of Heishanxia reach of the Yellow River. From the point of view of ensuring the long-term safety of the Yellow River water resources and building the national water network system of “four-horizontal and three-vertical”, this paper puts forward some opinions on the possible development schemes and the issues that need to be further studied. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

(Objective) Some rivers have islands. Their soil composition and geometrical shape influence water flow and sediment transport in the rivers. The purpose of this paper is to study the impact of flow rate and flowing duration on sediment erosion and hydrodynamic flow in a bended river. (Method) The study is based on two-dimensional average shallow water flow and sediment transport over riverbeds. Both water flow and sediment transport are solved using the MIKE 21. The model is applied to the section of Yellow River at Yongfeng Ferry in Ningxia province, where there are several small islands.(Result) When water flows for 3 hours at rate of 1 545 m³/s, sediment erosion reduces water velocity by 0.06~0.27 m/s and water depth by 0.02~0.32 m, compared with the results calculated without considering sediment erosion. Continuous erosion tends to stabilize water depth and flow rate. The deepest erosion depth is 0.16 m after water flows for 3 hours at rate 1 545 m³/s, and this increases to 0.24 m after the flow is increased to 6 hours at the same rate; their associated maximum deposition depth is 0.12 m and 0.23 m respectively. With the increase in flow rate and flow duration, the riverbed stabilizes, though erosion depth and deposition thickness continue to change. (Conclusion ) Sediment erosion increases the stability of hydrodynamic flow in the river, and the riverbed morphology does not change after flow rate exceeds a critical rate. These simulated results are consistent and can be used to help improve river management. [ABSTRACT FROM AUTHOR]

In recent years, ecological problems in the middle and lower reaches of the Yellow River have been frequent. Therefore, exploring its core influences can advance the implementation of "Ecological Protection and High-quality Development of the Yellow River Basin". This paper constructs an indicator system based on PSR guidelines, evaluates the ecological protection level of 55 cities in the middle and lower reaches of the Yellow River from 2009 to 2019, and uses correlation analysis with geographically and temporally weighted regression (GTWR) model to explore the spatial distribution characteristics of influencing factors, such as intensity of fertilizer application, amount of agricultural film applied, afforestation area per capita, and green technology innovation level on the ecological protection level. It is found that the overall level of ecological protection has shown a steady increase, but the spatial distribution varies widely. The ecological level increased from 0.2218 to 0.3357, showing a decreasing distribution trend from coastal to inland. Furthermore, it is found that the ecological protection level has a significant positive spatial correlation, mainly for similar clustering. The Global Moran's I for ecological protection level is greater than 0, and the Moran scatter plot has a high number of cities distributed in the first and third quadrants. There is a heterogeneity in the spatial and temporal distribution of factors influencing the level of ecological protection. Fertilizer application, the agricultural film uses, and afforestation area per capita are mainly negatively affected, while green innovation level has a strong positive effect, and agricultural film use, afforestation area per capita, and green innovation level become the core influencing factor of different regions. Therefore, in the middle and lower reaches of the Yellow River, the ecological protection level should be improved by implementing a regional differentiated development strategy, realizing cross-regional linkages between cities and focusing on differences in core driving factors. [ABSTRACT FROM AUTHOR]

In order to scientifically analyze the coordination degree between various water use processes, this paper proposed the coordination degree indicator to quantify the multiple water use process coordination degree based on the competition and cooperation relationship of multiple water users. Taking the Yellow River Basin as the study area, this paper quantified the long-term evolution process of cooperation degree, competition degree and coordination degree among 3 water use processes ( off-stream water supply, in-stream sediment transport water and instream ecological water). The results show that during 1988-2019, the cooperation degree is low ( mean value 0.06) while the competition degree is high ( mean value 0.33) ; the coordination degree changes between 0.10-0.82 ( mean value 0.46) ; the coordination degree shows a trend of increasing-decreasing-increasing after 2002, and the mutation points are 2012 and 2016; natural runoff, unified water regulation and reservoir operation mode impact the coordination degree of multiple water use processes in the Yellow River Basin. Under the influence of runoff attenuation and water use growth, the low coordination degree of multiple water use processes will exist for a long time in the Yellow River Basin. [ABSTRACT FROM AUTHOR]

Key ecological function areas are not only recognized as the critical subject for national and global ecosystem protection, but also the crucial hinterland for maintaining the livelihood of local residents. Studies on livelihood resilience contribute to better understand the adaptation strategies and development needs of poor and highly vulnerable groups in key ecological function zones, which is crucial to promoting the long run sustainability. Based on the survey data of 575 households, this paper constructs the livelihood resilience evaluation index system from three dimensions of buffer capacity, self-organization ability and learning ability. The method of weighted sum is used to evaluate the livelihood resilience of farmers, and the influencing factors are analyzed by multiple regression model. The results show that the overall level of livelihood resilience of farmers is weak, and the self-organization ability of farmers is significantly higher than their buffering ability and learning ability. We found that ecological policy, age of head of household, diversity of livelihoods, family size, and environmental dependence are the key factors that affect the resilience of farmers' livelihoods. We argued that, new methods such as establishing a technical training system for farmers, promoting livelihood diversity, improving and implementing active ecological policies, and building long-term and effective risk warning, emergency response, and poverty alleviation mechanisms should be considered and implemented. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hyperconcentrated turbidity currents typically display non-Newtonian characteristics that influence sediment transport and morphological evolution in alluvial rivers. However, hydro-sediment-morphological processes involving hyperconcentrated turbidity currents are poorly understood, with little known about the effect of the non-Newtonian rheology. The current paper extends a recent two-dimensional double layer-averaged model to incorporate non-Newtonian constitutive relations. The extended model is benchmarked against experimental and numerical data for cases including subaerial mud flow, subaqueous debris flow, and reservoir turbidity currents. The computational results agree well with observations for the subaerial mud flow and independent numerical simulations of subaqueous debris flow. Differences between the non-Newtonian and Newtonian model results become more pronounced in terms of propagation distance and sediment transport rate as sediment concentration increases. The model is then applied to turbidity currents in the Guxian Reservoir planned for middle Yellow River, China, which connects to a tributary featuring hyperconcentrated sediment-laden flow. The non-Newtonian model predicts slower propagation of turbidity currents and more significant bed aggradation at the confluence between the tributary Wuding River and the Yellow River in the reservoir than its Newtonian counterpart. This difference in model performance could be of considerable importance when optimizing reservoir operation schemes. [ABSTRACT FROM AUTHOR]

This paper presents numerical simulations regarding the transport characteristics of soil salt. It has been recognized in recent years that the growth and output of crops in the irrigation area of the lower reaches of the Yellow River are affected by the decreased fertility of soil as a result of the transport of soil salt, due to the long-term farming, fertilization of farmland which contains a high proportion of sands. Accordingly, numerical simulations by Hydrus are carried out, in which, based on the similarity principle, two-dimensional convection-diffusion partial-differential governing equations of unsteady flow in saturated-unsaturated porous media are applied to depict the motion parameters' spatial variability of soil water in the irrigation area. And the van Genuchten equation is adopted to express the relationship between volumetric water content and soil hydraulic conductivity and negative soil water pressure. The irrigation basin of the People's Victory Canal, which is downstream of the Yellow River, is investigated in detail as an example. The findings revealed that soil salt in the irrigation region is transferred by water diffusion, with irrigation and fertilization being the primary causes of downward migration and salt accumulation. It benefits the soil in irrigation areas and protects groundwater. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Our planet is increasingly threatened by degradation in water quantity and quality due to climate change, population growth and development pressures. Water shortage is one of the most challenging environmental problems to humankind in the 21st century under the changing climate. Water shortages and scarcity escalate risks to food security and economic viability. For decades, water management has been dominated by supply oriented paradigm of expanding the capacity of accessible water (e.g. building dams). While large scale infrastructure projects provided effective solutions for chronic water crises in the past, they have come at expensive, irreversible and delayed ecological, economic and social costs. As more questions are raised concerning over reliance on infrastructure solutions, discussions about a sustainable future suggest a greater focus on the demand side of the equation is needed. In this paper, we use multi-recursive and runoff coefficient analysis methods to analyze the annual runoff of the mainstreams (Kuye River, Tuwei River, Wuding River and Jialu River) in the middle reaches of Yellow River. The main objective is to estimate the impacts of climate change and human activity on water resources in the study area and test the potential of water demand management to lessen the gap between supply and demand. Results show remarkable drop in the average annual runoff as a combined effect of climate change and human activity. Moreover, results show that human activities are the direct reason for the changes of river runoff, and the proportion of human activities account the biggest is Wuding river, next is Kuye river, Jialu river is smallest, these changes lead to the decrease of river runoff, and even drying up in recent years. This result highlights the importance of using WDM to diminish the increasing gap between demand and supply. Motivated by this, the paper presents a comprehensive framework for implementation WDM in the middle reaches of Yellow River. The framework includes a wide range of instruments: legislative, economic, technological and educational. The core step of the framework, collaboration among water planners, water service providers and end-users lies as an essential mechanism for achieving long term trade-offs between ecological and socio-economic water needs. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spatially detailed characterization of the distribution amount and timing of river ice are important for identifying and predicting potential ice hazards. In this paper, we present an asynchronous river ice extraction and change detection method using multi-temporal SAR image and multi-spectral image. River channel information is a strong prior knowledge for ice detection and analysis. Therefore a river channel extraction algorithm on multi-spectral image based on sparse reconstruction is proposed and adopted in our method. The extracted river channel is used as prior information to effectively eliminate most interference regions on the shore. Then an adaptive threshold segmentation method is adopted to accurately detect river ice regions in SAR image. Fuzzy C-means clustering is used to segment river ice using the infrared bands of multi-spectral image, considering temperature can provide significant information to discriminate ice, water and shore. Finally, change analysis is done based on the ice extractions results of two kinds of images. The proposed method is applied on the Yellow River ice monitoring and experiments demonstrated that this straightforward approach works well with both SAR image and multi-spectral image. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The changes of runoff in the middle reaches of the Yellow River basin of China have received considerable attention owing to their sharply decline during recent decades. In this paper, the impacts of rainfall characteristics and land use and cover change on water yields in the Jingle sub-basin of the middle reaches of the Yellow River basin were investigated using a combination of statistical analysis and hydrological simulations. The Levenberg Marquardt and Analysis of Variance methods were used to construct multivariate, nonlinear, model equations between runoff coefficient and rainfall intensity and vegetation coverage. The land use changes from 1971 to 2017 were ascertained using transition matrix analysis. The impact of land use on water yields was estimated using the M-EIES hydrological model. The results show that the runoff during flood season (July to September) decreased significantly after 2000, whereas slightly decreasing trend was detected for precipitation. Furthermore, there were increase in short, intense, rainfall events after 2000 and this rainfall events were more conducive to flood generation. The "Grain for Green" project was carried out in 1999, and the land use in the middle reaches of the Yellow River improved significantly, which make the vegetation coverage (Vc) of the Jingle sub-basin increased by 13%. When Vc approaches 48%, the runoff coefficient decreased to the lowest, and the vegetation conditions have the greatest effect on reducing runoff. Both land use and climate can change the water yield in the basin, but for areas where land use has significantly improved, the impact of land use change on water yield plays a dominant role. The results acquired in this study provide a useful reference for water resources planning and soil and water conservation in the erodible areas of the middle reaches of the Yellow River basin. [ABSTRACT FROM AUTHOR]

In this paper, the multi-polar coupling mid-long term prediction method based on Sea Surface Temperature (SST) was introduced into the upper reaches of the Yellow River where China's water resources are relatively scarce. A mid-long term prediction model for the inflow runoff of Longyangxia Reservoir in the upper reaches of the Yellow River was constructed based on SST. The influence factors that dominate the runoff in the upper reaches of the Yellow River were found. The case study shows that the model built in this paper significantly reduces the forecast error (the forecast error decreases from -21% to -2.5% during the period from April to June 2018), which verifies the rationality of the model, the effectiveness of introducing the new technology and the stability of forecasting accuracy. It provides reference for other projects of medium and long-term runoff forecasting. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The source region of the Yellow River, located in the north-eastern edge of the Qinghai-Tibet Plateau, is an important water conservation region and ecological barrier of the Yellow River. In this paper, based on remote sensing technology, multi-period Landsat remote sensing images in the source region were taken as the main information source. With the assistance of field investigation, we monitored the spatial and temporal changes of desertification in the source region from 2000 to 2019. The results show that the area of desertification in the source region has accounted for 9.36% of the total area, of which the light desertification land is the major portion. The desertification is mainly distributed between the southern margin of Madoi Valley basin and the northern margin of Heihe Valley basin, and is distributed on the river valleys, lakesides, ancient rivers and piedmont proluvial fan, showing the form of patches, sheets and belts. The growth rate of desertification in the source region was 87.47% from 2000 to 2010. With a high growth rate, the process of desertification was represented by the rapid spread of desertification. From 2010 to 2019, the growth rate of desertification was 37.32%, which was relatively slow. But the moderate desertification land maintained a straight linear growth trend, showing an increasing trend of desertification degree. Through the analysis of the driving factors of desertification in the source region of the Yellow River, this paper argues that the special geographical location, climatic factors, rodent damages and human activities are the main causes of desertification. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Affected by the rare autumn rain in West China, severe autumn floods occurred in the middle and lower reaches of the Yellow River in 2021. In the face of the flood situation, in accordance with the principle of “system, overall planning, science and safety”, with the concept of comprehensively balancing flood storage and release space and reasonable sharing of flood risk as the dispatching concept, through the fine dispatching water project, Huayuankou twice more than 10000 m³/s flood had been reduced to about 4800 m³/s, successfully fighting the autumn flood. During the autumn flood season, there were no major dangers, major disasters or casualties, ensuring the safe flow of flood waters into the sea, preventing the displacement of 1.4 million people and the inundation of 266 thousand hectares of farmland in the downstream flood-plain, and ensuring the safety of people’s lives and property in the downstream flood-plain. This paper briefly introduced the situation of autumn flood control in 2021, summarized the concept of this flood control, and put forward the understanding of doing a good job in autumn flood control and prevention. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reservoir sedimentation usually occurs in rivers that carry heavy amounts of silt. Setting reasonable schedules for drainage hole operations can balance the reservoir sediment levels and downstream river morphology. China's Yellow River is well known for its abundant sediment supply. The Xiaolangdi Reservoir is the key control project for the main stem of the Yellow River, and its sediment accumulation is especially serious. Preventing sedimentation before the gates is an important issue. The characteristics of the flow and sediment before the intake towers under scheduled drainage hole operations should be thoroughly researched. In this study, a three-dimensional numerical model was established based on MIKE 3. Variations of the flow structure, sediment concentration, and sedimentation elevation were the parameters studied under the scheduled operations. The results showed that the features of the bend flow are developed during the model phase. The velocity distribution in the vertical direction does not follow the general logarithmic distribution law of open channels. Scouring funnels appear during the development of the sedimentation surface before the intake towers. The sedimentation elevation is lower than the permissible value and has no influence on gate operations. This paper can provide a reference for similar research. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the observed runoff and sediment data from Lijin hydrological station during the period of 1950–2018, this paper addressed the long-term change characteristics of runoff and sediment fluxes into the sea from the Yellow River. The Mann-Kendall test was adopt to estimate the long-term trends in the runoff and sediment time series. The Mann-Whitney-Pettitt (MWP) test were used to determine the change points of runoff and sediment time series. It could be concluded that the annual runoff and the sediment fluxes decreased significantly at the rates of −6.17×109 m³/a and −0.213×109 t/a, respectively. The changes during the flood season were more dramatic than in the dry season, especially for the sediment flux. Different significant change points are detected in the runoff and sediment time series. The changing point for the runoff occurred in 1968, 1985, and 2002 and those of sediment flux in 1968, 1985, and 1996, respectively. The negative long-term change trend and the occurrence of change points are highly associated to natural variation and human activities in the Yellow River basin. The occurrence time of some change points accords even with man-made events. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)