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天山北麓中段拗陷带地下水库的特征及其开发利用建议 总被引：1，自引：2，他引：1
本文在对天山北麓中段山前拗陷带地下水库的各项特征进行总结的基础上,将天山北麓中段山前拗陷带划分为5个巨型地下水库,它们具有储存量大、补给条件好、调蓄能力强、供水保证程度高、水质优良等诸多优点。进而提出了地下水库勘察评价、开发与保护的4点建议:①尽快开展天山北麓构造洼地巨型地下水库天然和人工调蓄能力的勘察评价,为水资源合理利用提供科学依据;②山前构造洼地巨型地下水库是首选饮水水源和重要的工业供水基地;③优化渠系利用方式,实现地表水与地下水联合利用;④实施地下水保护战略,确保人民群众饮水长治久安。 相似文献
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The Nahal Yatir Bedload Transport Database arises from the Northern Negev River Sediment Monitoring Programme and represents the first body of bedload information to be collected during flash floods in desert gravel-bed streams. Bedload flux was established automatically with three slot-samplers of the Birkbeck type. This was complemented by hydraulic measurements that allow sediment transport to be rated against channel average shear stress and specific stream power. Bed material and bedload grain-size distributions are also provided. The database is given in both printed and electronic tabular format. 相似文献
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Comparatively little is known about the hydrology of desert flash-floods despite the extent of the world's drylands. There is even less known about their sedimentary behaviour and particularly about the movement of coarse material as bedload. The results of an intense field monitoring programme carried out on an ephemeral gravel-bed stream in the northern Negev Desert are presented. In this semi-arid setting, flow duration analysis indicates that the channel is hydrologically active for 2% of the time, or about seven days per year, and that overbank flow can be expected for only 0·03% of the time—about three hours per year. Multipeaked flood hydrographs are the norm, reflecting many factors including the arrival of separate slugs of discharge from contributing subcatchments. The passage of the initial flood bore is surprisingly slow, but the rising limb of the flood hydrograph is rapid with a median time of rise of 10 minutes, in keeping with expected flash-flood behaviour. Bedload flux is high, averaging 2·67 kg s−1 m−1 during the period that the channel carries flow. This gives very high bedload sediment yield despite the infrequent and short duration of flood flows and matches the high yield of suspended sediment. The relationship between bedload flux and boundary shear stress is simple, in contrast with perennial gravel-bed streams, and the exponent of the log–log relationship is 1·52. Of great value is that the behaviour of the Nahal Eshtemoa corroborates a pattern established by the authors previously in a smaller tributary stream. © 1998 John Wiley & Sons, Ltd. 相似文献
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