Search

Ecological protection and high-quality development in the Yellow River Basin has become a major national strategy, and the coupling coordination of economic growth, industrial development and ecology in this area is becoming a research hot spot. This paper analyzed the coupling coordination mechanism of economic growth, industrial development and ecology in the Yellow River Basin and constructed an evaluation index system of coupling coordination degree. Using the coupling coordination model, the spatial autocorrelation model and grey relational model, this paper analyzed the space differences and time differences of the coupling coordination degree of 62 cities in the Yellow River Basin and their driving factors from 2012 to 2018, And the GM (1, 1) gray prediction method was used to predict the coupling coordination degree in the short term. The results showed that：① The overall level of economic growth, industrial development and ecology in the Yellow River Basin had shown a steady trend, and there were no significant differences in the speed of development. However, the coupling coordination of them was seriously out of coordination, and the coupling coordination of ecological protection and high-quality development in the Yellow River Basin had not yet reached a coordinated level,② The coupling coordination degree demonstrated significant global and local spatial autocorrelation features. The global spatial auto-correlation was positive and the convergence features were obvious. (3) The forecast results showed that the coupling coordination degree remained generally stable and coordination had not been reached during the forecast period in this area. The rate of improvement was relatively slow. Finally, a support system incorporating organizational guarantee, spatial governance, policy guarantee and institutional mechanism was established for economic growth and ecological protection in the Yellow River Basin. It is expected that this paper can provide a theoretical basis and lay a certain scientific decision-making foundation for the ecological protection and high-quality development in the Yellow River Basin, [ABSTRACT FROM AUTHOR]

The upper Yellow River basin is located in the new Silk Road economic belt. Fundamental to the healthy development of the Yellow River ecosystem and the security of water resources in the economic belt are the hydrological regime change that drives river ecosystem processes, or called ecological flow regimes (EFR). When developing a sustainable and ecofriendly Silk Road economic belt, the evaluation of the alteration of the EFR and an attribute analysis should receive great attention because they can provide decision makers with more information on ecological implications for balancing environmental and human water needs. The objective of this paper is to investigate the EFR variation at the Lanzhou gauge as the control section of the upper Yellow River basin. First, the paper addresses the macroscale EFR using ecoflow metrics (ecodeficit and ecosurplus), i.e., the multi-year trend of the annual and seasonal changes in ecological flow. Second, it evaluates microscale variations in EFR via the Yellow River ecohydrological index system and compares them with macroscale changes in EFR to verify their consistency. Third, it analyzes the attributes of EFR variation and determines the impact of the construction and operation of reservoirs on the variation. Results show that macro- and microscale EFR at the Lanzhou gauge have significant changes before and after the construction of reservoirs in the upper Yellow River basin, reaching a high degree of alteration. Reservoir construction and operation have been the major reason for the alteration of EFR in the past few decades, and the cascade reservoir regulation has more significantly affected the changes in EFR than has a single reservoir, placing the downstream fluvial ecological system under serious risk. This change should arouse considerable concern, particularly in the development of the new Silk Road economic belt. In addition, ecoflow metrics used for reflecting the macroscale change in this study are highly correlated with microscale indicators of EFR that are accepted in the upper Yellow River basin. This result implies that ecoflow metrics can mirror most ecological information from these microscale indicators and are suitable for the evaluation of alterations in hydrological processes at annual and seasonal timescales. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell 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.)

For decades, the Chinese government has been searching for solutions to cope with the increasing imbalance between the supply and demand of water in the Yellow River Basin. This paper aims at a better understanding of the development of the water allocation regime in the Yellow River Basin between 1950 and 2009, introducing a fresh perspective based on the notion of 'regime transition'. Accordingly, we investigated 1) whether so-called 'Windows of Opportunity for Transition (WOPTs)' emerged, triggering a transition, and whether WOPT(s) resulted in a stable transition towards the new regime; 2) how informal learning processes and epistemic communities have contributed to the regime change. We adapted Kingdon's 'multiple stream model' and identified four WOPTs from the 1950s, analyzing the reconfiguration process of the regime after the onset of the transition. Our examples of two types of informal learning processes demonstrate their contribution to the creation of WOPTs and the reconfiguration of the regime. Furthermore, this study indicates, in a qualitative manner, how epistemic communities contribute to the knowledge base of the regime, and thus to its development. Finally, we have provided a general insight into the further development of the water allocation regime and highlighted potential avenues for further studies. [ABSTRACT FROM AUTHOR]

Understanding the factors affecting irrigation management performance is crucial for sustainable resource use, especially with the decentralized management mode of irrigation systems being implemented in rural China. This paper contributes to the research field by incorporating different categories of social trust and perceived organization support (POS) into the analysis of irrigation management performance, by linking multiple elements that are based on the Institutional Analysis and Development (IAD) framework. We employed principal component analysis (PCA) and ordered probit regression to analyze a database covering 785 households in the upstream of the Yellow River basin. The results suggested that social trust and POS positively affected the irrigation management performance, and social trust strengthened the positive effect of POS on the performance. Furthermore, the results indicated that personal trust and institutional trust, as well as perceived emotional support and physical support, positively affected the performance. In addition, we also found that household characteristics, household cognition, group characteristics, physical conditions, and rules-in-use also had significant impact on the performance. This paper can be used to inform the government that social trust and POS need to be considered in the common-pool resources (CPRs) management. [ABSTRACT FROM AUTHOR]

It is important to manage water resources of the upper Yellow River basin for the new Silk Road economic belt. In recent decades, under the combined human activities and influence of climate, the hydrologic regime of the upper Yellow River basin shows remarkable variations that have caused many issues. So potential human indicated influence has been drawing increasing attention from hydrologists and local governments. The aim of this study is to determine the changes in the hydrological characteristic parameters and mean annual runoff series of the upper Yellow River basin. This paper took the representative Lanzhou Station in the upstream Yellow River as an example, used the TFPW-MK mutation test and rank sum test to analyze the location of the variation points of hydrological series. 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. The variation range of hydrological ecological indexes before and after variation were analyzed by the method of indicators of hydrologic alteration (IHA). The results show: a) the hydrological series of Lanzhou Station is a significant decreasing trend can be observed in the natural stream flow series in 1985 with a high degree of hydrological variability, while human activities play an important role; b) various ecological indicators have changed in different degrees that have caused the deterioration of ecological conditions around 1985; and c) continuous decreasing stream flow in the upper Yellow River basin will trigger serious shortages of fresh water in the future, which may challenge the sustainability and safety of water resource development in the river basin, and should be paid great attention before 2020. Variation analysis and diagnosis of eco-hydrological indexes in the upper reaches of the Yellow River can provide a basis for the development, utilization, and protection of water resources in this area. [ABSTRACT FROM AUTHOR]

A series of annual natural runoff recorded at eight hydrological stations in the Yellow River basin (YRB) and distributed at the main channel and two sub-basins (Weihe basin and Fenhe basin) are studied during the period from 1951 to 1998. The trends and the beginning points (or abrupt changes) of these series are detected with Mann-Kendall test (M-K test) and its progressive application. The results show that there are similar trends for different stations. The annual natural runoff series, except for stations of Lanzhou, Hekouzhen, and Longmen, have a downward tendency at some stations whose beginning points of the trend or abrupt changes occurred in the early or mid 1990s. However, their initial years of decrease are different. The decreasing trend of runoff has led to drying-up in lower reaches of the YRB, a water resources scarcity crisis, and a deterioration of the ecosystem. The reasons for the trends have been analyzed in this paper The trends of precipitation in the corresponding regions are similar to those of annual natural runoff It is an important aspect for runoff decrease. In addition, human activities have changed the hydrological cycle and lead to a reduction in runoff to a certain degree. Finally, two countermeasures for the runoff decrease are put forward. One is to develop water savings in irrigation regions, and the other is to plan South-to-North water transfer projects for the YRB. However the conflict between supply and demand will still exist for a long time because of the water scarcity in the future. [ABSTRACT FROM AUTHOR]

Soil erosion is a severe ecological problem. Most conventional methodologies for soil-erosion assessment are appropriate for small or medium river basins. This paper presents an approach to soil-erosion intensity assessment in large basins, utilizing coded polygons identified by spatially overlapping gradation levels of primary environmental factors. Efficient assessment of soil- erosion intensity is achieved by matching the coded polygons to selected polygons pre-assigned to reference groups. A case study is presented for the soil-erosion assessment of the Yellow River Basin. It is found that the calculated and observed soil-erosion intensities are in close agreement for 86% of the total area. Sensitivity analysis indicates that acceptable results are obtained using a 5% sample of the original 9,921 coded polygons, thus reducing substantially the computational load. Direct comparisons between the polygon codes in the reference and test groups show that uncertainty is reduced with respect to previous methods. This is confirmed by the reduction in information entropy from 7.49 to 1.33. The proposed approach should be of particular use in the cost-effective assessment of soil erosion in large basins. [ABSTRACT FROM AUTHOR]

As the buffer zone is the bridge between the river and surrounding territory, it experiences remarkable response to hydrological variance due to dam construction. To identify the accumulated impacts, two adjacent buffer zone sections of similar size on the Yellow River were compared. A time series of land cover distributions were analysed for changes of the buffer zones. After the dam service, a large area of wetlands and water area disappeared in the section with dam, which was also the consequence of the sedimentation in the reservoir. The areal extent for seven types of land cover was analysed in the buffer zone at distances of 10 and 5.5 km from the river. The land cover transition matrices within the 10 km zone for three time periods (1976-1996) were calculated to further clarify the transformation process. The farmland in the 10 km zone of dam increased 3 times in three decades, but it just rose the 50 % in the zone without dam. The land cover transition matrices analysis indicated that the major transitions in the dammed section were wetland, grassland and water area to farmland, as well as the mutual transformation of water area and wetlands. Two sections of the critical buffer zone within 5.5 km of the water were delineated into ten independent, 0.5 km annular gradient zones to determine the spatial variation of grassland, water area and wetland. The gradient zone analysis demonstrated that the dam construction accelerated the appearance of wetlands and also caused considerable pressure on the water and grassland area types. Upon comparing these temporal and spatial aspects, the increase of farmlands and wetlands in the earliest period was found to be the direct result of damming. The weakening hydrological alteration due to damming was concluded to significantly affect the temporal-spatial variations of the river buffer zone, particularly in the 5.5 km distance. [ABSTRACT FROM AUTHOR]

Abstract: For this paper, according to the statistics of water resources amounts and utilization needs, we carried out a water resources security preliminary evaluation from the following points of view: water consumption balance analysis, available water resources analysis, supply-demand water resources balance analysis, and overall water resources security analysis for the Yellow River Basin in 2009. The results of the research show that the consumption rate in 2009 was 75.5% for the Yellow River Basin. The total amount of local water in the Yellow River Basin was 58.210 billion m3, but both the supply water and the amount of available water are very low. Meanwhile, from the point of view of net water consumption, the deficit water resource amounts to16.763 billion m3, and in view of the size of the water supply, the deficit water resources amounts to 16.12 billion m3. The current deficit has been created by over-exploiting groundwater, squeezing ecological water consumption, re-using wastewater, and utilizing brackish water, sea water. Therefore, the water supply in the Yellow River Basin is not sustainable, and so it is not secure. As there exist issues in terms of the water resource and in terms of socioeconomic security and ecological security in the Yellow River Basin, we can conclude that the present Yellow River water resource is not reliable, which means that this water resource may not be able to meet future normal demands for living, production, and ecology maintenance. [Copyright &y& Elsevier]

Abstract: Rapid land use change has taken place in many arid and semi-arid regions of China over the past decade, such as in Yellow River Basin. In this paper, changes in the land use pattern of the Yellow River Basin were analyzed using Landsat TM data in 1990, 1995 and 2000. The aim was to improve the understanding of changes in land use with a view to identifying potentially more sustainable systems of land use. Firstly, the mathematical methodology was explored and developed for spatial pattern changes of land use, which include the degree index model of land use dynamic, index model of land use degree, mean center model of land use and transformation model of land use. Based on these models, the changing spatial patterns of land use were calculated and analyzed. During the period 1990–2000, the areas of cropland, built-up land and unused land all increased, the area of cropland increased dramatically by 2917km2, while the areas of grassland and woodland decreased by 4668 and 33km2, respectively. Meanwhile, the spatial pattern of land use also experienced a great change. Then the driving factors of land use change were investigated, the governmental policies on eco-environmental protection, population growth and meteorological conditions were the major factors that caused the land use change in the past decade. [Copyright &y& Elsevier]

We use Mann-Kendall trend test and Lepage method to study spatial and temporal variations of the streamflow series over the past 50 years based on daily hydrologic data from six gauging stations in the Yellow River basin. Research results indicate that: (1) The streamflow of the Yellow River basin is decreasing and water resource deficit tends to be more serious from the upper to the lower Yellow River basin; (2) Zero-flow days are observed after 1970 and overwhelmingly prevail during 1990-2000. Moreover, zero-flow events are observed mainly during spring and summer; (3) Low flow events are more sensitive to climatic changes and human activities when compared to the high flow events, which is mainly reflected by larger fluctuation of timing of change points. Furthermore, the timing of change point of hydrologic events tends to be earlier from the upper to the lower Yellow River basin, indicating more intensive impacts of human activities on water resource in the lower Yellow River basin. The current research will be greatly helpful for sound and effective water resource management in the Yellow River basin, being characterized by serious water deficit. [ABSTRACT FROM AUTHOR]

Abstract: In the previous studies, a method was developed to assess soil erosion based on land use information. In this paper, we present another approach that uses environmental data to assess soil erosion. A soil erosion characteristic index EI is proposed, and its value is derived using the Analytic Hierarchy Process (AHP) technique based on standardized environmental information stored in minimum polygons that tile the erodible area under consideration. The approach is applied to a case study of the Yellow River basin, north China, where serious erosion is occurring. To represent different grades of soil erosion, the range of EI is divided into six levels according to standard grades of soil erosion intensity. The application indicates that the method deals properly with data scarcity, with the results giving a satisfactory representation of the characteristics of soil erosion in the Yellow River basin. The spatial–temporal distribution of EI in the Yellow River basin is predicted, and the results interpreted to give the long-term trend and state of soil depletion. Comparisons are given between EI and surveyed soil erosion zoning maps for the Yellow River basin at the end of the 1980s and 1990s. The output reliability and the approach applicability in smaller spatial scales are investigated in a case study of Zhifanggou basin. [Copyright &y& Elsevier]

Land use and land cover change is an important driving force for changes in ecosystem services. We defined several important human-induced land cover change processes such as Ecological Restoration Project, Cropland Expansion, Land Degradation, and Urbanization by the land use/land cover transition matrix method. We studied human-induced land cover changes in the Yellow River Basin from 1980 to 2015 and evaluated its impact on ecosystem service values by the benefit transfer method and elasticity coefficient. The results show that the cumulative area of human-induced land cover change reaches 65.71 million ha from 1980 to 2015, which is close to the total area of the Yellow River Basin. Before 2000, Ecological Restoration Project was the most important human-induced land cover change process. However, due to the large amount of cropland expansion and land degradation, the area of natural vegetation was reduced and the ecosystem value declined. Since 2000, due to the implementation of the “Grain for Green” program, the natural vegetation of upstream area and midstream area of Yellow River Basin has been significantly improved. This implies that under an appropriate policy framework, a small amount of human-induced land cover change can also improve ecosystem services significantly. [ABSTRACT FROM AUTHOR]

Climate variability and human activities are two driving factors in the hydrological cycle. The analysis of river basin hydrological response to this change in the past and future is scientifically essential for the improvement of water resource and land management. Using a water balance model based on Fu' equation, the attribution of climate variability and land-use/land-cover change (LUCC) for natural runoff decrease was quantitatively assessed in the Yellow River Basin (YRB). With five general circulation model (GCM) s' output provided by The Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), future runoff in the context of climate change was projected. The results show that (1) compared with other distributed hydrological models, the water balance model in this study has fewer parameters and simpler calculation methods, thus having advantages in hydrological simulation and projection in large scale; (2) during the last 50 years, the annual precipitation and runoff have decreased, while the mean temperature has increased in the YRB. The decrease of natural runoff between natural period (1961 to 1985) and impacted period (1986 to 2011) could be attributed to 27.1-49.8 and 50.2-72.9% from climate variability and LUCC, respectively. As the LUCC is the major driving factor of the decrease in the upper and middle reaches of the YRB, policymakers could focus on water resources management. While climate variability makes more contribution in the middle and lower reaches of the YRB, it is essential to study the impact of future climate change on water resources under different climate change scenarios, for planning and management agencies; (3) temperature and precipitation in the YRB were predicted to increase under RCP4.5. It means that the YRB will become warmer and wetter in the future. If we assume the land-use/land-cover condition during 2011 to 2050 is the same as that during 1986 to 2011, future annual average natural runoff in the YRB will increase by 14.4 to 16.8%. However, future runoff will still be lower than the average value during 1961 to 1985. In other words, although future climate change will cause the increase of natural runoff in the YRB, the negative effect of underlying surface condition variation is stronger. It is necessary to promote the sustainable development and utilization of water resources and to enhance adaptation capacity so as to reduce the vulnerability of the water resources system to climate change and human activities. [ABSTRACT FROM AUTHOR]

River runoff is affected by many factors, including long-term effects such as climate change that alter rainfall-runoff relationships, and short-term effects related to human intervention (e.g., dam construction, land-use and land-cover change (LUCC)). Discharge from the Yellow River system has been modified in numerous ways over the past century, not only as a result of increased demands for water from agriculture and industry, but also due to hydrological disturbance from LUCC, climate change and the construction of dams. The combined effect of these disturbances may have led to water shortages. Considering that there has been little change in long-term precipitation, dramatic decreases in water discharge may be attributed mainly to human activities, such as water usage, water transportation and dam construction. LUCC may also affect water availability, but the relative contribution of LUCC to changing discharge is unclear. In this study, the impact of LUCC on natural discharge (not including anthropogenic usage) is quantified using an attribution approach based on satellite land cover and discharge data. A retention parameter is used to relate LUCC to changes in discharge. We find that LUCC is the primary factor, and more dominant than climate change, in driving the reduction in discharge during 1956-2012, especially from the mid-1980s to the end-1990s. The ratio of each land class to total basin area changed significantly over the study period. Forestland and cropland increased by about 0.58% and 1.41%, respectively, and unused land decreased by 1.16%. Together, these variations resulted in changes in the retention parameter, and runoff generation showed a significant decrease after the mid-1980s. Our findings highlight the importance of LUCC to runoff generation at the basin scale, and improve our understanding of the influence of LUCC on basin-scale hydrology. [ABSTRACT FROM AUTHOR]

This article employs the case of the Yellow River basin to advance understanding of the water–energy–food nexus by demonstrating how the country’s energy and agriculture sectors are competing for limited water supplies and by quantifying the future water demands in the two sectors. The results show that in 2030 the water demands for food and energy are likely to increase by less than 4 km3and 1 km3, respectively, in the Yellow River basin. The analysis suggests that agricultural water savings and inter-basin water transfers are the main ways to ensure sufficient water flows through the basin to fulfil demand for both sectors while preserving the natural ecosystems. [ABSTRACT FROM PUBLISHER]

In the Yellow River basin, China, ecosystems suffer from the overexploitation and utilization of water resources, resulting in various environmental impacts. Consideration must be given to both human and ecosystem water requirements in water resources management. A water footprint (WF) is a tool for estimating industrial, agricultural, commercial and household water requirements and for examining the impact of consumption on water resources. The study attempts to establish an approach to analyse the dynamic processes and driving forces that result in certain WFs. Using input-output tables for provinces and municipalities, we calculate water use coefficients, the total WF and the net external WF of consumption in China's Yellow River Basin. A biproportional algorithm is employed to revise the input-output tables for analysing the temporal dynamics of the WF. The factor analysis and linear regression were used to analyse the main influencing factors of WF. Results indicate that the coefficient for water use by primary industries is highest and that coefficients for provincial water use differ significantly. Second, household consumption and residuals from capital accumulation constituted approximately half of the total WF of the Yellow River basin in 2002 and also differed significantly among provinces. Third, the ratio of the net external WF to the total WF increased, and the ratio of final consumption to the total WF declined during the period examined. Fourth, output by secondary industries correlated most strongly with the WF, followed by area under irrigation, per capita meat consumption, water consumption per 10,000-yuan increase in added value and population. [ABSTRACT FROM AUTHOR]

The Palmer indices (PIs) that have been most widely used for drought monitoring and assessment are criticized for two main drawbacks: coarse hydrological accounting processes with a simplified two-stage bucket soil water balance model and arbitrary rules for defining drought properties and standardizing index values through limited calibration and comparison. In this study, we introduce a new proposal of the VIC hydrologic model-based Palmer drought scheme, where traditional PIs (e.g. PDSI) can readily be calculated on the basis of distributed finescale hydrologic simulations. Moreover, recent variants of PI (i.e., SPDI and SPDI-JDI) also provide a preferable standardization strategy that allows probabilistic invariability and better spatio-temporal comparability of computed drought indices. Using gridded meteorological forcing, soil and vegetation data to drive the three-layer VIC model, both non-VIC and VIC-based PIs are investigated to examine their performances for drought characterization and detection. Results indicate that VIC hydrologic model would allow for adjustments in statistical properties of computed PDSI and VIC-based SPDI is also preferable to PDSI for better statistical robustness and spatio-temporal consistency/comparability. Moreover, the joint SPDI-JDI has the strength of integrating multi-scale probabilistic properties and drought information released by individual SPDI, providing overall drought conditions that take into account the onset, persistence and termination of droughts. At proposed 0.25° grid scale, the VIC-based SPDI-JDI indicates high frequency and long total time of drought condition in the Yellow River basin (YRB), China. Although no significant temporal trends are found in identified drought duration and severity, both the seasonal and annual drought index values demonstrate a downward trend (higher drought intensity) for considerable proportions of the YRB. These findings imply high drought risk and potential drying stress for this region. The new framework of hydrologic model-based PIs can help to strengthen our knowledge and/or practices in regional drought monitoring and assessment. [ABSTRACT FROM AUTHOR]

The Yellow River Basin is one of China's most densely-populated, fastest growing and most dynamic regions, with abundant natural resources and intense agricultural production. Major land policies have recently resulted in remarkable landscape modifications throughout the basin. The availability of precise regional land cover change information is crucial to better understand the prevailing dynamics and underlying factors influencing the current processes in such a complex system and can additionally serve as a valuable component for modeling and decision making. Such comprehensive and detailed information is lacking for the Yellow River Basin so far. In this study, we derived land cover characteristics and dynamics from the complete last decade based on optical high-temporal MODIS Normalized Differenced Vegetation Index (NDVI) time series for the whole Yellow River Basin. After filtering and smoothing for noise reduction with the use of the adaptive Savitzky-Golay filter, the processed time series was used to derive a large variety of phenological and annual metrics. The final classifications for the basin (2003 and 2013) were based on a random forest classifier, trained by reference samples from very high-resolution imagery. The accuracy assessment for all 18 thematic classes, which was based on a 30% reference data split, yielded an overall accuracy of 87% and 84% for 2003 and 2013, respectively. Major land cover and land use changes during the last decade have occurred on the Loess Plateau, where land and conservation reforms triggered large-scale recovery of grassland and shrubland habitat that had been previously covered by agriculture or sparse vegetation. Agricultural encroachment and urban area expansion are other processes influencing the dynamics in the basin. The necessity for regionally-adapted land cover maps becomes obvious when our land cover products are compared to existing global products, where thematic accuracy remains low, particularly in a heterogeneous landscape, such as the Yellow River Basin. The basin-wide novel land cover and land use products of the Yellow River Basin hold a large potential for climate, hydrology and biodiversity modelers, as well as river basin and regional governmental authorities and will be shared upon request. [ABSTRACT FROM AUTHOR]

Partitioning precipitation ( P) between streamflow ( Q) and actual evapotranspiration ( Ea) on a basin scale is controlled by climate change in combination with catchment characteristics. Fu's formulation of the Budyko framework was used to estimate Q as a function of two meteorological variables, P and potential evaporation ( Ep), and one adjustable parameter reflecting characteristics of catchment conditions ( ω). Results show that ω reflects the impacts of catchment characteristics on the partitioning of P between Q and Ea for the different water yielding regions. As predicted, Q was more sensitive to P than to comparable changes in Ep for the whole of the Yellow River Basin ( YRB), a water-limited basin, while it was shown to be highly sensitive to changes in P, Ep, and ω in the low water yielding region ( LWYR) of the basin, followed by YRB and the high water yielding region of the basin. The high sensitivity of Q to P, Ep, and ω in LWYR indicates that the management of catchments within these zones is critical to the management of overall basin flow, mitigating impacts of climate change on Q. The Budyko framework, incorporating the adjustable parameter ω, outlines interactions between Q, climate, and characteristics specific to different water yielding regions. It also provides a new approach in understanding hydrological process response to climate change. Due to the obscure physical attributes of ω, an explanation of the parameter using soil or vegetation characteristics will aid in the understanding of the eco-hydrological behaviour of catchments and help to provide more detailed catchment management options for which to mitigate climate change with respect to concerns regarding agricultural water usage. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this research, drought in Yellow River basin has been studied by using dry spells. Three indices, including the maximum length (MxDS), mean length (MDS) and number of dry spells (NDS), and five periods (annual, winter, spring, summer and autumn) are considered. The results show that a south to north gradient for mean MxDS and MDS has been dominantly found in all periods except summer, in which a southwest and southeast to north gradient exists. Mean NDS shows an opposite distribution to that of mean MxDS and MDS. It is surely that the northern part of Yellow River basin, with a higher MxDS and MDS and lower NDS, is much drier than southern part in a regional scale. According to temporal analysis by using the Mann-Kendall trend method, MxDS of most stations show negative but insignificant trends during annual and winter, while the majority of stations show positive trends during spring, summer and autumn. Trends of MDS and NDS dominantly depict positive and negative for most periods, respectively. By comparing the frequency of dry spells during the ENSO events, it can be found that the frequency of intermediate and long dry spells is almost tantamount during the occurrence periods of El Niño and La Niña. [ABSTRACT FROM AUTHOR]

The management of large river basins, such as the Yellow River Basin (YRB) in China, is complicated by distributed, localized decision processes and by mechanisms that coordinate local decisions and manage basin-level issues. Since 1998, the Yellow River Conservancy Commission (YRCC) has launched the Unified Water Flow Regulation (UWFR) as a centralized controlling mechanism that enforces an upper limit on water withdrawals (water use permits) for eight provinces located in the basin. The implementation of UWFR has maintained a prescribed minimum flow in the downstream channel and avoided the flow cutoff events that occurred every year between 1972 and 1998. This study attempts to explore the socioeconomic and environmental consequences of the regulation and test plans to improve water allocation management in the YRB. A decentralized optimization is combined with a multipleagent system (MAS) framework for the YRB, in which water users, reservoirs, and downstream ecological zones are defined as agents. This method iteratively determines water prices for each water use agent in the context of water market. The proposed water market scenario shows possible improvements of UWFR with respect to social, economic, and environmental objectives. [ABSTRACT FROM AUTHOR]

Copyright of Hydrological Sciences Journal/Journal des Sciences Hydrologiques is the property of Taylor & Francis Ltd 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 article focuses on the study which examines the temporal trends of reference evapotranspiration (ETref) in the Yellow River Basin (YRB), China. Sensitivity coefficients of ETref to meteorological variables were identified with contributions of key meteorological variables to the temporal trend of ET ref being detected. The sensitive regions for ET ref response to the changes of the four meteorological variables are not similar in the YRB.

The article presents a new hydrological model that was developed to examine the long-term water balance in the Yellow River Basin. Using the daily routine observation data and a high-resolution land surface classification map derived from remotely sensed data, the model predicted seasonal and long-term variation in river discharge and actual evapotranspiration in the source area of the Yellow River basin. The performance of the model was validated and its applicability to the source area of the Yellow River basin was also confirmed.

Using Landsat TM data from 1995 and 2000, changes in the landscape erosion pattern of the Yellow River Basin, China were analysed. The aim was to improve our understanding of soil-erosion change so that sustainable land use could be established. First, a soil-erosion intensity index model was developed to study soil-erosion intensity change in the study area. Over the 5 years, the areas of weak erosion, moderate erosion, severe erosion, and very severe erosion all increased. The area of weak erosion increased dramatically by 7.94×105 ha, and areas of slight erosion and acute erosion decreased by 1.93×106 ha and 4.50×104 ha, respectively. The results show that while the intensity of soil erosion has gradually been decreasing as a whole, in some regions the soil erosion is becoming more severe. Based on landscape indices, the pattern of changes in soil erosion over the past 5 years was analysed. The changes in landscape pattern of soil erosion resulted from human activities. Analysis showed that human impact increases fragmentation, having three major effects on landscape pattern, reduction in patch area, variations in patch shape, and changes in spatial pattern. In the study area, population growth, farming, governmental policy and forest degradation are the major factors causing soil erosion change over a 5-year period. [ABSTRACT FROM AUTHOR]

Based on monitoring data of 123 meteorological stations from 1960 to 2000 near or in the Yellow River Basin, the spatial and temporal distributions and their trends for pan evaporation (PE) are investigated in this study. The results indicate that, despite the annual mean air temperature over the Yellow River Basin has, on average, increased by 0.6° over the past 40 years, the rate of PE has steadily decreased, especially in summer and spring. Compared with the period of 1960s to 1970s, the rate of annual pan evaporation during 1980s to 1990s has decreased by 126mm or 7.0 percent Spatial distribution of the rate of change show that this kind of trend is general but not universal, PE has significantly decreased over the upper and lower reaches of the Yellow River, but increased to a small degree over the middle reaches. Further analyses show that the decrease of PE is mainly related to reductions in sunshine durations and solar irradiance, owing to more clouds and aerosols. [ABSTRACT FROM AUTHOR]

This study develops a water distribution control model to manage and operate a multi-purpose, multi-reservoir system in the Yellow River Basin. The aim is to make the best use of limited water resources and to coordinate different uses. The overall control task is made up of two processes. An initial distribution scheme is obtained through a simulation model first, then the scheme's output suggestions are adjusted by a harmony index which is considered as a feedback regulator and the order parameter in synergetic theory is applied in this regulator Control criteria and a subsequent application of the method are presented. Case studies indicate that the proposed control process facilitates quick and efficient distribution control and can provide both theoretical and technical support for sustainable water resources development in the Yellow River in China. [ABSTRACT FROM AUTHOR]