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81.
AbstractThe hydrology of water-dependent ecosystems around the world has been altered as a result of flow regulation and extraction for a variety of purposes including agricultural and urban water supply. The flow regime of the Murray-Darling Basin in Australia is no exception, with attendant impacts on the health of the environment. Restoration of parts of the flow regime is a key feature of environmental flow delivery. However, environmental flow delivery in a system that is managed primarily to provide a secure and stable supply for irrigation presents challenges for managers seeking to return more natural flow variability in line with ecosystem requirements. The institutional arrangements governing releases of water from storage can influence the ability of managers to respond to natural cues, such as naturally rising flows in a river. As such, the legal and governance aspects of environmental flow delivery are likely to be important influences on the outcomes achieved.
Editor Z.W. Kundzewicz; Guest editor M. AcremanCitation Banks, S.A. and Docker, B.B., 2014. Delivering environmental flows in the Murray-Darling Basin (Australia)—legal and governance aspects. Hydrological Sciences Journal, 59 (3–4), 688–699. 相似文献
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SCI-E干旱区研究重要期刊与投稿指南 总被引:1,自引:1,他引:0
应用文献计量学方法,在对1997--2005年SCI-E收录的世界干旱区研究论文进行统计、分析、研究的基础上,通过期刊发义量指标(V1)、论文被引次数指标(V2)和期刊影响因子(V3)三项指标的加权综合评判分析,评选出世界范围内干旱区研究领域的28种重要期刊。介绍了世界干旱区研究重要期刊的相关投稿信息。 相似文献
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Environmental isotopic and hydrochemical study of groundwater in the Ejina Basin,northwest China 总被引:5,自引:0,他引:5
The study investigates the groundwater evolution and its residence time in the Ejina Basin, northwest China according to isotope
and hydrochemical analyses results. The groundwater chemistry is mainly controlled by the dissolution of halite, Glauber’s
salt, gypsum, dolomite and calcite, also influenced by other processes such as evaporation, ion exchange, and deposition.
Based on tritium content in atmospheric precipitation and by adopting a model with exponential time distribution function,
the mean residence time of the unconfined aquifer groundwater with fairly high tritium activities (21–49 TU) is evaluated.
The results show that these groundwaters have low residence time (5–120 years) and are renewable. In contrast, the deep confined
groundwaters are tritium-free and radiocarbon values range from 18.3 to 26.7 pmc. According to the most commonly used 14C correction models, the radiocarbon groundwater ages were calculated which yield ages of approximately 4,087–9,364 years
BP. Isotopic signatures indicate formation of deep confined groundwaters in a colder and wetter climate during the late Pleistocene
and Holocene. It is suggested that long-term, rational water usage guide should be set up for the Heihe River Basin as a whole
to permit a considerable discharge to the Ejina Basin. 相似文献
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The physico‐chemical characteristics and microbial composition of the final effluents of two municipal wastewater treatment plants in South Africa were assessed between July and September 2009. The impact of the treated final effluents on the receiving water bodies was also evaluated. The temperature across all sampling points ranged between 14 and 22°C, while pH varied from 6.9 to 7.6. High levels of turbidity, chemical oxygen demand (COD), ammonia, nitrate, nitrite and orthophosphate (PO4) were observed in many cases. Turbidity of the samples was in the range of 2.2–288.6 NTU. The concentrations (mg/L) of other physico‐chemical parameters are as follows: COD (9.33–289); ammonia (0.000340–45.4); nitrate (0.062–539); nitrite (0.021–22.6); PO4 (5.3–33.2). The microbial quality of the effluents discharged from the plants did not comply with the limits set by the South African guidelines with respect to pathogens such as Salmonella, Shigella, Escherichia coli, total coliform, faecal coliform, enterococci, faecal streptococci, and viral particles for effluents intended for discharge into receiving watersheds. This study revealed an undesirable impact on the physico‐chemical and microbial qualities of the receiving water bodies as a result of the discharge of inadequately treated effluents from the wastewater treatment facilities. This poses a health risk to several rural communities which rely on the receiving water bodies primarily as their sources of domestic water and recreational purposes. There is therefore a need for the intervention of appropriate regulatory agencies in South Africa to ensure compliance of treatment facilities with wastewater effluent quality standards. 相似文献
88.
Late Holocene upper bounds of flood magnitudes and twentieth century large floods in the ungauged, hyperarid alluvial Nahal Arava, Israel 总被引:1,自引:0,他引:1
Yael Jacoby Tamir Grodek Yehouda Enzel Naomi Porat Eric V. McDonald Ofer Dahan 《Geomorphology》2008,95(3-4):274-294
The impact of large twentieth century floods on the riparian vegetation and channel morphology of the relatively wide anabranching and braided Nahal Arava, southern Israel, was documented as part of developing tools to (a) identify recent large floods, (b) determine these flood's respective magnitudes in alluvial ungauged streams, and (c) determine long-term upper bounds to flood stages and magnitudes. Along most of its course Nahal Paran, a major tributary that impacts the morphology, floods and sediments of Nahal Arava at the study reach, is a coarse-gravel, braided ephemeral stream. Downstream of the Arava–Paran confluence, aeolian and fluvial sand delivered from eastern Arava valley alters the channel morphology. The sand has accreted up to 2.5 m above the distinct current channels, facilitating the recording of large floods. This sand enhances the establishment of denser riparian vegetation (mainly Tamarix nilotica and Haloxylon persicum) that interacts with floods and affects stream morphology. A temporal association was found between specific floods recorded upstream and tree-ring ages of re-growth of flood-damaged tamarix trees (‘Sigafoos trees’) in the past 30 years. This association can be utilized for developing a twentieth century flood chronology in hyperarid ungauged basins in the region. The minimum magnitude of the largest flood that covered the entire channel width, estimated from flood deposits, is approximately 1700–1800 m3s− 1. This is a larger magnitude than the largest gauged flood of 1150 m3s− 1 that occurred in 1970 about 30 km upstream in Nahal Paran. Our estimation agrees with flood magnitude estimated from the regional envelope curve of the largest floods. Based on Holocene alluvial stratigraphy and OSL dating in the study reach we also conclude that flood stages did not reach the late Holocene ( 2.2 ka) surface and therefore we estimate a non-exceedance upper bound of 2000 m3s− 1 flood magnitudes for Nahal Arava during that interval. This study indicates that in unfavorable areas the combination of hydrology, fluvial morphology and botanic evidence can increase our understanding of ungauged basins and give information crucial for hydrology planning. 相似文献
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