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Ma Z.,Tsinghua University | Wang Z.,Tsinghua University | Zheng H.,Tsinghua University | Gippel C.J.,Fluvial Systems Pty Ltd. | Speed R.,Okeanos Pty Ltd.
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2012

This paper develops an ecological water use scheduling model for the lower reach of Yellow River, focusing on simulation for maintaining an acceptable level of river health. Results show that under current water demands, the instream ecological water use can be largely provided through scheduling the use. In the future, if the water resources infrastructure and inter-basin water transfers remain unaltered, however, water deficits in social-economic demands and environmental demands will rise dramatically, as all the former demands are increasing. Implementation of water demand management, water transferring from other basins and new reservoir building, all can contribute to reduction in the predicted future water deficit. Of these measures, demand management is the most efficient, while reservoir building the least efficient. In terms of reduction in total deficit volume, implementation of the west line of south-to-north water diversion project is the most effective. However, it produces a lower marginal benefit of reducing water deficit. © right. Source

Liu X.-Q.,CAS Wuhan Institute of Hydrobiology | Gippel C.J.,Griffith University | Gippel C.J.,Fluvial Systems Pty Ltd. | Wang H.-Z.,CAS Wuhan Institute of Hydrobiology | And 2 more authors.
Limnology | Year: 2016

We describe an approach to assessing biological health in a heavily utilized, large lowland river setting, using the example of the lower Yellow River, China. In this study, the river was divided into four reaches, and a field survey of fish, benthic macroinvertebrates, and riparian plants was undertaken. Data from historical records were used for reference. The scoring system used weighting to adjust for differences in the importance of the chosen indicators and the relative efficiency of the sampling effort. The results indicated that the biological health of the lower Yellow River is distant from historical reference conditions, with its condition generally declining in the downstream direction. This result is consistent with the river’s history of impairment of hydrology, water quality, wetland area and character, and physical form. We conclude that the reference river state based on historical conditions is unlikely to equate to the best attainable river health because certain changes have occurred in the river that may prohibit a return to the previous state of ecological health. On the basis of the results of this assessment as well as a review of the literature, we propose field data collection methodologies and indicators that can be applied in future assessments. © 2016 The Japanese Society of Limnology Source

Ma Z.Z.,Tsinghua University | Wang Z.J.,Tsinghua University | Xia T.,Tsinghua University | Gippel C.J.,Fluvial Systems Pty Ltd. | Speed R.,Okeanos Pty Ltd.
Journal of Environmental Informatics | Year: 2014

With the evolution of society and increasing population, increasing amounts of water resources are being developed to support the needs for such commodities as water and energy, but this development has significantly changed the hydrologic processes in many rivers from their natural state. In this paper, a hydrograph-based hydrologic alteration assessment (HHA) is proposed to describe the hydrologic regime with the attributes of biodiversity and river health, and to assess the hydrologic regime alteration impacted by four main reservoirs in seven sections in the trunk of the Yellow River, and also a comparison to IHA-RVA. The results indicate the following: (1) the hydrologic regimes in the Yellow River have experienced significant changes, from upstream to downstream, corresponding to the construction and operation of the reservoirs; (2) the Sanmenxia reservoir in middle reach has a relatively smaller influence on the hydrologic regime than the largest reservoir of Longyangxia in upper reach; and the hydrologic alteration in the midstream reach is less than in the upstream and downstream reaches; and (3) HHA and IHA are both suitable for assessing hydrologic regime alteration, but HHA is benefit to diagnose the regulation of reservoirs, and IHA places more significance than HHA on the extreme mean flow, which is an advantage in small-discharge regimes and a disadvantage in large-discharge regimes in terms of biodiversity and river health. © 2014 ISEIS All rights reserved. Source

Zhang Y.,Chinese Research Academy of Environmental Sciences | Wang D.,Chinese Research Academy of Environmental Sciences | Wang D.,Hebei United University | Wang X.,Renmin University of China | And 2 more authors.
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae | Year: 2012

Environmental flow is the foundation for achieving rational water allocation. With fish species being the protection target in Taizi River, a model combining flow components and fish ecology is proposed by referring to the FLOWS method. Thereafter the environmental flow components including base flow, pulse flow, bankfull flow and overbank flow in Taizi River are calculated via integration with the hydraulic relationships between habitat indicators and flow magnitude. Results indicate that the annual base flow at Benxi Reach, Liaoyang Reach and Tangmazhai Reach is 293 million m3, 312 million m3 and 288 million m3, respectively. Although the current streamflow can meet the overall annual base flow requirement, the hydrological process has to be controlled by reservoir operation to match fish ecological process. A series of hydrological parameters reflecting the consistency between the environmental flow and the natural flow process, such as the magnitude, frequency, duration and timing of pulse flow, bankful flow and overbank flow, has also been recommend for the three reaches of Taizi River. The research findings can provide the theoretical basis for reservoir ecological dispatch in Taizi River. Source

Kong W.,Chinese Research Academy of Environmental Sciences | Meng W.,Chinese Research Academy of Environmental Sciences | Zhang Y.,Chinese Research Academy of Environmental Sciences | Gippel C.,University of Melbourne | And 2 more authors.
Ecological Research | Year: 2013

The ecoregion is currently widely used as the basic geospatial unit in freshwater biodiversity conservation. The popularly used delineation is usually based on the assumption that attributes of aquatic ecosystems are influenced by landscape-scale environmental variables. However, few ecoregion delineations attempt to establish the local validity of this assumption prior to delineation, and few studies check the correspondence of the derived ecoregion boundaries with the distributions of attributes of aquatic biota. In this study, we established an approach to overcome these shortcomings. The notable features of the approach are: (1) the delineation variables were filtered through a series of analytical steps to select those that best represented the aquatic community traits, and which avoided redundancy in the data; (2) the method was quantitative and repeatable; and (3) the derived ecoregion boundaries were checked for consistency with the spatial attributes of aquatic biota. The approach was applied in the Taizi River Basin, northeast China. The procedure proposed here filtered out altitude and annual precipitation as the best variables to include in the freshwater ecoregion delineation. Then, using the quantitative ISODATA classification method, the basin was classified into three ecoregions. A test of accuracy indicated that freshwater ecoregions matched well with the spatial distribution pattern of macroinvertebrate community attributes. Statistical analysis showed that natural geographical attributes and river attributes were different in the three ecoregions, and indices representing macroinvertebrate community attributes are significantly different as a whole among the three ecoregions. The case study proved this approach effective on ecoregion delineation. © 2013 The Ecological Society of Japan. Source

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